Airborne system for deagglomeration, dispersal and characterization of particles

Abstract

An airborne system and method for deagglomeration, dispersal and characterization of particles is provided for dispersing particles into the atmosphere and for capturing and characterizing airborne particles. Example systems include a particle supply and a dispersal assembly configured to receive energy and airflow from an aerial platform and to controllably release deagglomerated particles into an atmospheric environment. In some embodiments, particles are conditioned prior to or during release to reduce aggregation and promote predictable dispersion behavior. Additional components may be provided for sensing, control, and capture of airborne particles for physical and chemical characterization. The disclosed systems and methods are applicable to a variety of atmospheric dispersion, monitoring, and testing applications.

Description

P-635226-PCAIRBORNE SYSTEM FOR DEAGGLOMERATION, DISPERSAL AND CHARACTERIZATION OF PARTICLESPRIORITY CLAIM

[0001] The present application claims priority to U.S. Provisional Patent Application No.63 / 738,853, entitled, “AERIAL DISPERSAL OF REFLECTIVE PARTICLES,” filed on December 26, 2024, which application is incorporated herein by reference in its entirety.BACKGROUND OF THE INVENTION1. TECHNICAL FIELD

[0002] The present invention relates to the field of dispersing deagglomerated particles from an aerial platform and / or characterization of dispersed particles on an aerial platform, including particles used for solar climate intervention (SCI) by solar radiation modification or management (SRM), which deals with ways of countering global warming by reducing incoming sunlight, and, more particularly, to stratospheric aerosol injection (SAI). Technologies for reducing incoming sunlight lie under a broader family of climate intervention (CI) technologies are referred to hereinafter.2. DISCUSSION OF RELATED ART

[0003] The dispersion of particles into the atmosphere presents a set of technical considerations distinct from those encountered in confined or controlled environments. Once released into the air, particles may be influenced by atmospheric motion, turbulence, gravitational settling, and interactions with surrounding air masses, resulting in complex and often difficult-to -predict behavior. Factors such as particle size, mass, and aggregation state can affect how particles are transported, distributed, and retained in the atmosphere. Accordingly, the controlled introduction and dispersion of particles into atmospheric environments remains a subject of ongoing technical interest, particularly in applications requiring predictable behavior following release.

[0004] One current area of interest in particle dispersal relates to dispersing particles in the atmosphere for SRM. The ongoing rise in global temperatures and the predicted acceleration of climate change and associated risks including extreme weather events, food crises, and economic burdens demand the attention of the scientific community and investigation of a wide range of mitigation approaches. Anthropogenic greenhouse gas (GHG) emissions, the driving force behind the acceleration of global warming, are linked to virtually all aspects that enabled economic development in the 20th century; as a consequence, the sustainable reduction ofP-635226-PCemissions across the world requires extensive technological investments and advances across a multitude of sectors, as well as broad agreement within states and in the international community in the face of complex political and diplomatic dynamics. The amounts of GHGs already accumulated in the atmosphere since the industrial revolution - over a trillion tons of CO2, with an estimated lifetime of centuries - will continue to burden the environment for decades even in the most optimistic scenarios of carbon capture technologies and emission reductions. With these understandings in mind, it is imperative that the efforts for emission reduction policies and technologies be complemented by other initiatives that will enable a manageable climate future in the 21st century.

[0005] A wide array of approaches for climate change mitigation are being studied, including emissions reduction, climate change adaptation, and a portfolio of climate intervention technologies termed "Climate Intervention" (CI). The two sets of CI technologies are CO2 removal (CDR) and Solar Climate Intervention (SCI), also referred to as Solar Radiation Modification / Management (SRM). CDR addresses the root cause of the climate crisis; however, it is far from technological and operational readiness, in terms of scalability and effectiveness. On the other hand, SRM strategies are intended to directly induce cooling effects, and thus offer a more immediate way of countering global warming. This approach is considered a temporary measure, potentially "buying time" until other processes have developed enough to allow greenhouse gases reduction, and may be implemented until CDR approaches prove effective, or in addition thereto.

[0006] The premise of the SRM approach is that global temperatures are fundamentally linked to a balance between the amount of incoming solar radiation that reaches the ground, and the amount of atmospheric insulation caused by GHGs; thus, if the balance has been changed by an increase on the insulation side, it can be recovered by reduction of the incoming radiation. As an order of magnitude, a reduction of the average incoming solar flux by about 1% would more than balance the insulating effect of current GHG burdens added since the industrial age. The scientific community has begun to examine several approaches for achieving this reduction, as reviewed for example by the National Academy of Sciences (“Reflecting Sunlight: Recommendations for Solar Geoengineering Research and Research Governance”, The National Academies Press, 2021). Several theoretical options for reducing sunlight, such as marine cloud brightening or cirrus cloud thinning, currently contain very high fundamental uncertainties in their capability to provide a predictable and controllable, global-scale solution to global warming; space-based options such as extremely large mirrors are unfeasible from economical or engineering aspects. On the other hand, one leading approach, StratosphericP-635226-PCAerosol Injection (SAI), is inspired by a naturally occurring phenomenon which repeatedly demonstrates a relatively simple and effective global cooling mechanism.

[0007] The eruption of the volcano Pinatubo in 1991 sent tens of millions of tons of sulfur dioxide high into the atmosphere, where it formed submicron-sized droplets of sulfuric acid in a thin layer that quickly enveloped the world. These droplets were very effective in reflecting sunlight; the following years exhibited a global climate that completely offset the warming effects of anthropogenic GHGs. The apparent simplicity of this temporary global scale “fix” inspires the SAI; in the US, research programs in this field are now expanding from academia to several National Labs. The decision to eventually deploy SRM to complement emission reduction efforts or not will have to be made by international cooperation. Responsible, sciencebased decision making by world governments will require extensive research of the efficiency and risks associated with any such approach, as well as continued analysis of the consequences of avoiding SRM.

[0008] One main difference between the proposed SRM concept and the natural case produced by volcanoes, as well as other proposed implementations of SRM intended to emulate them, is the composition of the stratospheric aerosol. Volcanic eruptions create droplets of sulfuric acid; while these aerosols are relatively efficient in reflecting sunlight, they come with a variety of drawbacks, such as increased ozone layer losses, heating of the stratosphere by absorption of outgoing infrared radiation, acidic precipitation, lack of potential attributability when monitoring specific effects (as large quantities of sulfates are already found in the stratosphere, creating a significant baseline presence) and a natural limit of the effect due to coagulation of droplets. The risks and uncertainties related with these effects can be mitigated by using alternative particles, such as solid, biosafe, submicron particles which are engineered to have the desired chemical inertness, optical efficiency, large-scale manufacturability, and the mechanical properties required for aerial dispersibility.SUMMARY OF THE INVENTION

[0001] The following is a simplified summary providing an initial understanding of the invention. The summary does not necessarily identify key elements nor limit the scope of the invention, but merely serves as an introduction to the following description.

[0002] One aspect of the present invention provides an aerial dispersal system configured to disperse reflective particles from an airplane, the system comprising a feeder of a powder comprising the reflective particles, which are configured to have diameters between 0.05pm and 10pm or between 0.1pm and 1pm and to not agglomerate, and a dispersal mechanismP-635226-PCconfigured to receive energy and compressed air from the airplane and to controllably disperse the particles from the airplane out to the stratosphere.

[0003] One aspect of the present invention provides a method of dispersing particles from an airplane, the method comprising controllably releasing compressed air from the airplane, while utilizing the Venturi principle to introduce the particles delivered from a feeder of a powder comprising the reflective particles into the air flow and out of the airplane, wherein the particles have diameters between 0.05pm and 10pm or between 0.1pm and 1pm and do not agglomerate.

[0004] Disclosed properties of the particles, which are disclosed herein, further contribute to the dispersal of the particles into the stratosphere as disclosed herein.

[0005] These, additional, and / or other aspects and / or advantages of the present invention are set forth in the detailed description which follows, possibly inferable from the detailed description, and / or learnable by practice of the present invention.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] For a better understanding of embodiments of the invention and to show how the same may be carried into effect, reference will now be made, purely by way of example, to the accompanying drawings in which like numerals designate corresponding elements or sections throughout. The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee. In the accompanying drawings:

[0007] Figures 1A-1C are high-level schematic block diagrams of an aerial dispersal plan and system, according to some embodiments of the invention.

[0008] Figure 2A is a high-level schematic illustration of aerial dispersal systems, according to some embodiments of the invention.

[0009] Figures 2B-2F provide schematic non-limiting illustrations of feeding configurations of the powder to the dispersal mechanism, according to some embodiments of the invention.

[0010] Figures 2G and 2H schematically illustrate embodiments of deagglomeration mechanisms, according to some embodiments of the invention.

[0011] Figures 21 and 2J illustrate experimental results concerning particle size distributions using a single eductor compared to using two eductors with an intermediate container, respectively, according to some embodiments of the invention.

[0012] Figures 3A and 3B illustrate an experimental example of a disperser with a nonlimiting example for a pattern of dispersal of particles, and an example for particle size distribution in a free jet, according to some embodiments of the invention.P-635226-PC

[0013] Figure 4 illustrates an application of aerial dispersal systems, according to some embodiments of the invention.

[0014] Figures 5A-5D provide non-limiting examples for particle size distributions upon dispersal, according to some embodiments of the invention.

[0015] Figure 6 is a high-level flowchart illustrating methods of dispersing particles from airplanes, according to some embodiments of the invention.

[0016] It will be appreciated that, for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.DETAILED DESCRIPTION OF THE INVENTION

[0017] In the following description, various aspects of the present invention are described. For purposes of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the present invention. However, it will also be apparent to one skilled in the art that the present invention may be practiced without the specific details presented herein. Furthermore, well known features may have been omitted or simplified in order not to obscure the present invention. With specific reference to the drawings, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.

[0018] Before at least one embodiment of the invention is explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is applicable to other embodiments that may be practiced or carried out in various ways as well as to combinations of the disclosed embodiments. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.

[0019] Some embodiments of the present invention provide efficient and economical methods and mechanisms for dispersing powders of reflective particles from airplanes to reduceP-635226-PCincoming sunlight radiation to counter global warming, and thereby provide improvements to the technological field of solar climate intervention (SCI) by solar radiation modification or management (SRM), and, more particularly, to stratospheric aerosol injection (SAI). Disclosed dispersal mechanisms may be used to disperse other types of solid particles of various shapes and sizes and may be used in other dispersal applications. Specific use cases provided below are non-limiting but serve merely to provide some implementation scenarios.

[0020] Some embodiments of the present invention provide efficient and economical methods and mechanisms for reducing incoming sunlight radiation to counter global warming due to greenhouse gases and thereby provide improvements to the technological field of climate intervention, based on stratospheric dispersal of disclosed particles. Disclosed particles may have optical characteristics that scatter sunlight upon dispersal in the stratosphere and their global dispersion in the stratosphere reduces the amount of incoming solar radiation that reaches the ground and / or mitigates global warming. The particles may be safe and inert with respect to interactions with molecules in the atmosphere, and particularly the stratosphere, and may be safe for humans and the environment in general. The particles may be produced in a highly controlled manner and may include various markings in trace amounts (e.g., trace metals, stable isotopes, and / or fluorescent materials, e.g., under at trace amounts of under 0.1 wt%) that enable monitoring the production and dispersal processes from the initial production through the dispersal scheme and up to sampling various regions of the atmosphere and ground for monitoring the effects of the dispersed particles. For example, the particles may comprise amorphous silica produced by a sol-gel process (e.g., the Stober sol-gel process but not limited to this production process), have diameters ranging between 0.1pm and 1 m that are suitable for SRM, and be produced as solid amorphous silica or as core-shell particles with dielectric cores that are safe (e.g., mineral or organic, as disclosed herein) and amorphous silica shells.

[0021] In some embodiments, disclosed dispersal systems and methods may be configured to disperse various types of other solid particles which may require deagglomeration, e.g., reflective particles such as natural minerals (e.g. calcite, silica, or alumina) or engineered particles (e.g. particles with cores, shells and / or coatings fabricated for specific chemical, optical and / or mechanical properties), as well as tracers or non-reflective particles.

[0022] Aerial dispersal systems, mechanisms and methods for dispersing reflective particles from airplanes are provided. Dispersal systems comprise a feeder of a powder comprising the reflective particles, which are configured to have diameters between 0.05pm and 10pm or between 0.1pm and 1pm and to minimize agglomeration, and a dispersal mechanism configured to receive energy and compressed air from the airplane and to controllably disperse the particles from the airplane out into the stratosphere. Various embodiments are provided forP-635226-PCcombinations of types of feeders and dispersal mechanisms, as well as supporting components for conveying and deagglomerating the powder, and for sensing and controlling the dispersal of the reflective particles.

[0023] For example, disclosed optimized dispersal systems may comprise (i) high density packing inside the aircraft while minimizing overhead weight, (ii) controlling the distribution of the particles exiting the aircraft and transferred to its hydrodynamic wake in a given plume scenario, and (iii) mitigating undesired particle coagulation while mixing the particles into the atmosphere. Since submicronic particles tend to generate high van der Waals inter-particle cohesive forces, the design of a dispersal system requires careful experimental validation and limits the choice for candidate particles. Disclosed embodiments overcome a degree of stickiness of the particles that may lead to their agglomeration, e.g., due to hydroxyl surface terminations (such as silanol groups on silica particles) that may form hydrogen bonds which lead to aggregation of the particles. For example, in the case of amorphous silica particles, binding of a coating comprising hydrophobic terminations such as methyl groups in place of silanol groups or as a steric hindrance can prevent the silanol groups from forming hydrogen bonds that aggregate the particles, change the hydrophilic nature of the amorphous silica, determined by the silanol groups, into the hydrophobic nature determined by the new surface termination groups, and reduce or prevent the reactivity of the spherical particles (through the silanol groups or otherwise), e.g., with water vapor, trace gases or sulfates in the atmosphere and particularly in the stratosphere.

[0024] In characterization tests of the powder of particles, physical and behavioral properties of different powders were analyzed with respect to their flowability and their transportability. Some of the disclosed powders were found to resist flow, being cohesive with respect to applied consolidating stress, having high internal friction angles (>50°), high wall friction angles (>30°), exhibiting high compressibility under consolidating stress (which nearly doubled the powder density) and lacking tendency to flow out freely of hoppers. These results indicate the need for particle coatings and / or for powder de-agglomeration and / or fluidization devices to enable easier or free flow of the disclosed powders through the dispersal system, as disclosed herein.

[0025] Figures 1A-1C are high-level schematic block diagrams of an aerial dispersal plan 100 and system 130, according to some embodiments of the invention. Figure 1A is a high-level schematic illustration of aerial dispersal plan 100, according to some embodiments of the invention. Figures IB and 1C are high-level schematic illustrations of aerial dispersal system 130, according to some embodiments of the invention.P-635226-PC

[0026] As illustrated schematically in Figure 1A, aerial dispersal system 130 is configured to disperse reflective particles from airplanes according to dispersion plan 100, which is devised to disperse the required amounts of particles for all latitudes and altitudes, with respect to the available airplane types and configurations in the airplane fleet. The multiple parameters that are used to determine dispersion plan 100 are indicated schematically as (i) a general dispersal plan 100A defining amounts of particles 102 and latitudes and altitudes 104 in which the particles are to be dispersed (based on various radiation scattering and stratospheric dispersal models), (ii) types of available airplanes 110 in the fleet, such as modified small jets 112, commercial flights by large jets 114 and / or specially designed airplanes 116 - each with specified characteristics such as available volume for the particles (referred to as amount of powder 105 per airplane and container types) and the performance of associated dispersal mechanisms, as well as available flight latitudes and altitudes, (iii) air sources 120 available to disperse the particles in the various types of airplanes, such as onboard cylinders of compressed air 122 (probably mainly for experimental purposes, due to weight considerations), specific bleed air throughputs 124 (depending on the type of airplane) and / or dedicated dispersal units 126 (e.g., including designated intake duct(s) for air to be used for the dispersal), which may be designed for specially designed airplanes 116 and / or for other types of airplanes, and (iv) logistic considerations 118 concerning the transportation and loading of the airplanes (at various takeoff and landing locations) with the required amounts of powder 105.

[0027] As illustrated schematically in Figure IB, in certain embodiments, aerial dispersal system 130 may be configured to disperse the reflective particles from the airplane, using feeder(s) 142 of powder 105 comprising the particles, which are configured to have diameters between 0.1pm and 10pm and to minimize agglomeration, and dispersal mechanism(s) 140 configured to receive energy and compressed air from the airplane and controllably disperse the particles from the airplane out into the stratosphere (see, e.g., Figures 2A-2F). The nonagglomerating particles enable using energy and compressed air from the airplane to disperse an amount of powder that fits into the fuselage of the airplane using available supply of energy and compressed air from the airplane.

[0028] In some embodiments, feeder(s) 142 may operate by gravity or by negative pressure and may include a feeding aid 143, a dosing mechanism 148 and a sensing and control mechanism 170. Aerial dispersal system 130 may further comprise a conveying mechanism 150 configured to convey powder 105 from feeder(s) 142 to dispersal mechanism 140, which may comprise a deagglomeration mechanism 180 for deagglomerating powder 105.

[0029] In some embodiments, feeder(s) 142 may operate by gravity. Feeding aid 143 may be configured to fluidize powder 105 using at least one hopper 145 (see, e.g., Figures 2A-2E) withP-635226-PCfluidizing elements, at least one vibrator and / or at least one fluidizer configured to fluidize the powder, and / or at least one vibration element. In some embodiments, dosing mechanism 148 may comprise at least one rotary valve, at least one pinch valve, at least one butterfly valve, and / or at least one gate valve. In various embodiments, sensing and control mechanism 170 may comprise scales and / or at least one powder surface level sensor. In some embodiments, conveying mechanism 150 may be configured to operate by negative pressure or by positive pressure. In various embodiments, deagglomeration mechanism 180 may comprise at least one eductor and / or at least one target onto which the powder is delivered, which may comprise a direct-impact target or a mesh. Examples for eductors include ejectors configured to maintain the ejected fluid (powder mixed in air) in constant motion, preventing sedimentation of the powder.

[0030] In some embodiments, powder 105 may be aerated prior to conveying. Aeration may be achieved by introducing gas into powder 105 within feeder 142 to expand the powder bed, reduce inter-particle friction, and improve particle mobility. Aeration may reduce cohesive effects, limit compaction, and promote more uniform powder entrainment into conveying mechanism 150. Aeration may occur continuously or intermittently and may be regulated based on mass flow rate, powder cohesion, or humidity conditions.

[0031] In some embodiments, sensing and control mechanism 170 may be further configured to monitor the rate at which powder 105 exits feeder 142 and enters conveying mechanism 150 or dispersal mechanism 140. The sensing and control mechanism 170 may determine the remaining mass of powder 105 within feeder 142, and may calculate or otherwise determine the mass flow rate of powder 105 being dispersed over time. These measurements may be used to adjust flow conditions, regulate dosing mechanism 148, or coordinate dispersal rate with available compressed air capacity. Real-time measurement data may be processed onboard the aerial platform using computer-implemented control logic to maintain dispersal rate accuracy during flight.

[0032] In certain embodiments, sensing and control mechanism 170 may further comprise one or more particle characterization sensors configured to monitor powder 105 during or immediately after dispersal. Such sensors may be configured to determine powder dispersal rate, particle size distribution, or electric charge distribution. Particle size distribution monitoring may be performed using optical scattering sensors, imaging sensors, aerodynamic particle sizing instruments, or other particle-measurement techniques capable of characterizing the size profile of dispersed particles. Electric charge distribution may be monitored using one or more electrostatic probes, electrical impactors, electrostatic precipitators, ion-measurementP-635226-PCsensors, or other instruments configured to detect the presence, magnitude or flux of electrical charge carried by particles 105.

[0033] In some embodiments, deagglomeration mechanism 180 may be configured to expose powder 105 to high-shear turbulent flow within dispersal mechanism 140. The term “high-shear turbulent flow” refers to flow conditions in which local velocity gradients within the compressed air induce differential particle velocities sufficient to overcome cohesive forces within agglomerates of powder 105. By increasing the turbulent shear rate, the compressed air flow may separate individual particles from clusters or agglomerates, thereby promoting uniform dispersal into the surrounding atmosphere.

[0034] In certain embodiments, dispersal mechanism 140 may further comprise one or more venturi ducts or tubes, nozzle throat constrictions, or other geometrical flow-constriction regions configured to create locally accelerated flow and associated pressure gradients. Passage of compressed air and entrained powder 105 through such constricted regions may generate shear layers, small-scale turbulent eddies, and / or rapid velocity transitions that deagglomerate particle clusters by shear stresses from drag forces from slip-velocity, turbulence and / or collisions between particles and surfaces or other particles. These effects may be amplified under conditions of high mass flow rate, elevated flow velocity, or larger static pressure differences within the venturi section.

[0035] In some embodiments, flow constriction regions within dispersal mechanism 140 may be shaped or dimensioned to increase turbulent dissipation rates and to establish high-shear flow fields. Such shear-intensive regions may enhance particle-to-particle collisions and particle-to-surface interactions, which further contribute to the breakdown of agglomerates. The venturi-oriented geometry may include converging-diverging sections or internal mixing features located upstream, within, or downstream of the dispersal orifice.

[0036] In certain embodiments, the deagglomeration mechanism 180 may be expressly configured to optimize the breakdown of agglomerates comprising submicron-scale particles. Submicron agglomerates may be particularly sensitive to fine-scale turbulent structures, including turbulent eddies and regions of high shear intensity. By tailoring the air velocity profile, the dispersal mechanism may promote particle trajectories that maximize residence time within regions of elevated shear and enhance the likelihood of particle-to-particle and particle-to-surface collision events capable of separating agglomerated particles.

[0037] In some embodiments, feeder(s) 142 and conveying mechanism 150 may operate by negative pressure. Feeding aid 143 may be configured to fluidize powder 105 using fluidizing element(s) configured to fluidize the powder and / or feeder(s) 142 may comprise at least one vibration element configured to vibrate at least one hopper 145 feeding the powder. VariousP-635226-PCembodiments may comprise other or additional means to enhance the flowing of the powder through aerial dispersal system 130 and possibly contribute to the deagglomeration of the powder.

[0038] In some embodiments, dosing mechanism 148 may be configured to control the negative pressure. In various embodiments, sensing and control mechanism 170 may comprise scales and / or at least one powder surface level sensor. In various embodiments, deagglomeration mechanism 180 may comprise at least one eductor and / or at least one target onto which the powder is delivered, which may comprise a direct-impact target or a mesh.

[0039] In some embodiments, feeding aid 143 may include one or more fluidizing elements designed to introduce low-pressure gas into powder 105 to expand or aerate the bulk material volume, thereby reducing particle compaction within feeder 142. The fluidizing elements may include porous plates, sparging tubes, gas-permeable membranes, or directed jets configured to distribute gas uniformly through powder 105. In certain embodiments, feeding aid 143 may further include one or more vibration elements such as external vibrators, internal agitators, or wall-mounted oscillation pads configured to reduce bridging, rat-holing, or other flow interruptions within feeder 142. The combination of fluidizing elements and vibration elements may increase flow uniformity and reduce mechanical resistance to transport through conveying mechanism 150.

[0040] In some embodiments, conveying mechanism 150 may be configured to operate by negative pressure, positive pressure, or mechanical propulsion. Mechanical propulsion may be achieved using one or more conveyor belts, screw conveyors, or moving belt surfaces configured to transfer powder 105 from feeder 142 to dispersal mechanism 140. Conveyor belt configurations may include open-belt or tubular-belt systems, with belt surfaces formed from materials selected to minimize adhesion and maintain uniform feed rate. In positive- or negative-pressure configurations, airflow may be used to maintain material suspension within enclosed conduits.

[0041] In some embodiments, dispersal mechanism 140 may include one or more discharge orifices configured to release powder 105, entrained within compressed air, into the surrounding atmosphere. The size, shape, orientation and position of the discharge orifice may be selected to control exit velocity, mass flow rate, plume direction, particle dispersion angle, uniformity of particle distribution and the interactions with the flow surrounding or trailing the dispersing platform. The discharge orifice may be circular, elliptical, slotted, rectangular, or otherwise contoured to optimize dispersion performance and deagglomeration under various flight and atmospheric conditions.P-635226-PC

[0042] In some embodiments, deagglomeration mechanism 180 may comprise at least two eductors arranged in series with an intermediate container or conduit positioned between them. Powder 105 may first be deagglomerated in a primary eductor that entrains the material within a compressed air stream, delivering the mixture into the intermediate container or conduit. Secondary eductor flow may reaccelerate the material and apply an additional deagglomeration stage, increasing the duration and intensity of turbulence, acceleration and / or particle-to-particle interactions. This serial configuration may improve agglomerate breakdown efficiency, particularly for cohesive or fine-particle powders.

[0043] In various embodiments, aerial dispersal system 130 may be configured to disperse an amount of powder 105 that fits into the fuselage of the airplane using available supply of energy and compressed air from the airplane. The compressed air may be supplied from a bleed air system of the airplane and / or from designated intake ducts. In various embodiments, aerial dispersal system 130 may be configured to disperse tens of tons of particles per flight.

[0044] In some embodiments, aerial dispersal system 130 may further comprise one or more inlets located along an exterior surface of the aerial platform and oriented to receive ram air generated by the forward motion of the platform during flight. As used herein, “ram air” refers to ambient atmospheric air that is forced into an inlet due to the dynamic pressure created by aircraft velocity. The ram air may be routed to one or more compression or regulation elements, including, for example, onboard compressors, air-gas turbines, and controlled ducting manifolds, and may be conditioned to serve as a source of compressed air for deagglomeration or dispersal.

[0045] In certain embodiments, the use of ram air as a compressed air source enables operation of dispersal mechanism 140 with reduced reliance on stored compressed air or turbine bleed air. One or more inlet ducts may be dimensioned or shaped to optimize airflow capture efficiency, reduce inlet losses, and maintain pressure suitable for delivery to dispersal mechanism 140.

[0046] In other embodiments, compressed air supplied to dispersal mechanism 140 may be provided by turbine engines of the aerial platform. Such engines may provide bleed air at elevated pressure, temperature, and flow rate. The compressed air supplied from these turbine engines may be conditioned, throttled, cooled, regulated, or otherwise modified and controlled to achieve a desired pressure, temperature, and volumetric flow rate suitable for deagglomeration and controlled dispersal.

[0047] For example, turbine engine output may be configured to provide compressed air having a flow rate sufficient to entrain powder 105 and to deliver deagglomeration forces consistent with the characteristics of powder 105, including the particle size distribution andP-635226-PCcohesive properties of any agglomerates. The compressed air delivered to dispersal mechanism 140 may also be temperature-adjusted to prevent unwanted condensation, icing, thermal clumping, or water adsorption on powder 105.Although compressed air may be provided from multiple onboard sources, including compressed air cylinders, bleed air taps, and ram air inlets, the system design may select or switch among sources based on power availability, required mass flow rate, desired dispersal rate, or operational efficiency. Multiple compressed air sources may be available simultaneously to satisfy the required pressure, temperature, and flow specifications for operation of dispersal mechanism 140.

[0048] In various embodiments, aerial dispersal system 130 may further comprise at least one sensor 175 for monitoring the particles immediately after their dispersal.

[0049] In various embodiments, the particles may comprise amorphous silica and / or calcium carbonate particles, core-shell particles and / or particles having a hydrophobic and unreactive coating. Aerial dispersal system 130 may be configured to disperse the particles at a rate of at least 1 ton / hr (or intermediate values), using compressed air at a throughput of at least 1 scm (standard cubic meters) per second.

[0050] As non-limiting, examples for various embodiments of aerial dispersal system 130, Tables 1A-1C indicate a range of alternative types of units in aerial dispersal system 130 (Table 1A), a range of alternative types of units in aerial dispersal system 130 with gravitational feeding (Table IB), and a range of alternative types of units in aerial dispersal system 130 with negative pressure feeding (Table 1C).

[0051] The alternatives for feeders 142 refer to the delivery of the powder from the storage (e.g., from hopper(s) 145), the alternatives for feeding aids 143 refer to aids used with the release of powder from hopper(s) 145 to down-stream processes, the alternatives for dosing mechanisms 148 refer to ways to does and meter the powder to achieve the required throughput to down-stream processes, the alternatives for sensing and control mechanisms 170 refer to sensors and controllers performing real-time measurements throughout the process, the alternatives for conveying mechanisms 150 refer to possible ways by which the powder is transported from dosing unit(s) 148 to down-stream processes, and deagglomeration mechanisms 180 refer to mechanism configured to ensure release of the powder at the required parameters, mainly with respect to the specified PSD (particle size distribution). The depicted combinations of units have been tested experimentally, to compare their performance and efficiency, as disclosed herein.P-635226-PCTable 1A: Alternative types of units in the aerial dispersal system.Table IB: Alternative types of units in the aerial dispersal system with gravitational feeding.5P-635226-PCTable 1C: Alternative types of units in the aerial dispersal system with negative pressure feeding.

[0052] It is noted that some alternatives that are not listed in Tables 1A-1C may still be used 5 in various embodiments, such as using a screw as a feeding aid, using a jet mill for deagglomeration, and so forth.

[0053] Certain embodiments comprise a globally dispersed amount of scattering particles (e.g., spherical particles with diameters ranging between 0.1pm and 1pm), over all latitudes in the stratosphere, with the amount and dispersion pattern of the particles configured to reduce 10 global incoming solar radiation to achieve a specified radiation reduction requirement.

[0054] Certain embodiments comprise an airplane fleet configured to disperse an amount of scattering particles, globally over all latitudes in the stratosphere to yield the target dispersion. The amount of particles per flight and the flight plan of the airplanes of the fleet may be configured to reduce global incoming solar radiation to achieve the specified radiation reduction 15 requirement. The airplane fleet may comprise, e.g., between 100-200 business jets modified to fly above 60kft, to disperse between 5-10 tons of particles per flight (the modified business jets may be of one or more types). The airplane fleet may be configured to carry out between 3-5 flights per day to disperse several teragrams of the particles per year. In certain embodiments, modified business jets may be further configured to provide at least 1 scm of compressed air 20 from their bleed air systems to disperse the particles (as a non-limiting example for modifications). It is understood that these numbers are presented by way of example only, and each may vary in further embodiments above or below the stated amounts.

[0055] In certain embodiments, the airplane fleet may comprise regular commercial planes configured to disperse the particles above the tropopause at mid latitudes and polar latitudes, 25 while the modified business jets may be used to disperse the particles above the tropopause at tropical latitudes.P-635226-PC

[0056] In some embodiments, the particles may be loaded onto the airplanes in unit load device (ULD) containers and dispersed therefrom using a low-weight dispersal mechanism. Using ULD containers allows for standardization and conformity with many types of airplanes. Various modular storage solutions may be used, as in other industrial systems. In various embodiments, various storage and dispersal methods and mechanisms may be employed, depending on the type of airplane and its performance, and configured to be adjusted to dedicated airplanes and / or to carry out a secondary operation of particle dispersal in addition to a main operation of the airplane (as further non-limiting examples for modifications). The particle powder may be fluidized using the given air supply rates, to enable application of widely used vibration modules and pneumatic transport systems to handle the sub-micron powders.

[0057] Conveying the powder may be carried out using negative pressure lines, from storage to the dispenser modules in a consistent and repeatable manner. A dosing system that connects the conveyor to the storage system was tested and validated, allowing for effective control of the particle flux

[0058] The disclosed systems and methods may be designed to satisfy multiple demands concerning safety and efficiency, at multiple levels starting from particle design, through dispersal methodology and reaching global operability and efficiency considerations. Safety of the particles upon breathing may be ensured by using amorphous silica particles, which are considered safe when having a diameter larger than 0.1pm. Moreover, amorphous silica particles are considered environmentally safe. Finally, amorphous silica is a chemically inert material, that does not react with other chemicals. It is understood that this diameter is presented by way of example only, and each may vary in further embodiments above or below the stated amount. Moreover, safety need not be a concern in further embodiments.

[0059] The target dispersion pattern of the particles may be configured to satisfy specified requirements to achieve an effect on the climate. A non-limiting example may include a performance requirement of balancing global warming by, e.g., reducing incoming radiation by IW / m2net globally-averaged flux with a specific global distribution (e.g., as a radiation reduction criterion). It is noted that the global effect is intended to reverse effects of global warming, rather than creating local cooling effects which may have unpredictable effects. The global approach is unique and requires a global dispersion that correlates to the global warming distribution that is to be balanced. The reduction of incoming radiation may be achieved by dispersing a specific amount of particles in a specific distribution, e.g., dispersing 1 Tg (teragram, 1012gr, million tons) of particles per year, globally, in a distribution that may be specified and using climate models and monitored. It is understood that these numbers areP-635226-PCpresented by way of example only, and each may vary in further embodiments above or below the stated amounts.

[0060] Considerations in configuring the airplane fleet and the flight plan of the airplanes over the year include the number of flights required and available for the different types of aircraft, with respect to the amount of particles and the compressed air throughput requirements, and configured to achieve the desired global distribution to satisfy the specified radiation reduction requirements. Correspondingly, particle design considerations (e.g., type of particle and coating, e.g., hydrophobic coating configured to reduce or prevent agglomeration of the particles) and a low-weight dispersal mechanism are provided to accommodate the global dispersal rate requirements. As disclosed herein, the particles may be loaded onto the airplanes in unit load device (ULD) containers and / or in designated containers (e.g., depending on the type of airplane and type of mission, as well as according to efficiency considerations), and dispersed therefrom. In some embodiments, particles may be stored in the airplanes in various compartments within the fuselage, the pressurized cabin or an unpressurized bay and / or within the wings to replace some of the fuel tanks or other free spaces. These spaces may also be used to store the mechanism(s) used to convey the particles to the dispersal units, which may be located in the pressurized cabin, in an unpressurized bay, or any other internal or external installation. Powder containers that are not ULDs may be loaded onto the airplanes using corresponding loading methods.

[0061] In some embodiments, aerial dispersal system 130 may be integrated into the aerial platform such that the center of gravity of the aircraft remains within allowable limits before, during, and after dispersal. Fuel mass may be redistributed among onboard fuel tanks during flight to counterbalance the reduction in powder mass within storage vessels as powder 105 is dispersed. Powder storage vessels may be positioned to span existing aircraft mass-centroid locations, enabling controlled mass depletion patterns that maintain center-of-gravity stability within required operating margins.

[0062] In certain embodiments, aerial dispersal system 130 may be configured to store and disperse at least one or two tons of powder 105 per flight. Powder storage vessels may be dimensioned to fit within available interior volume of the aerial platform, including fuselage compartments or modified cargo regions sized to accommodate powder mass on this scale. Compressed air and onboard energy systems may be selected or adjusted to support dispersal of these quantities within typical operational flight durations.

[0063] In some embodiments, dispersal mechanism 140 may be configured to disperse powder 105 at a rate of at least 1 tons per hour using compressed air delivered at a volumetric throughput of at least 1 standard cubic meter per second. This flow rate is by way of exampleP-635226-PConly and it may be lower or higher than that in further embodiments. Compressed air flow rate may be selected to achieve sufficient entrainment, turbulence, and deagglomeration efficiency to maintain a stable dispersal stream during operation. System performance may be constrained by available onboard energy, turbine bleed air supply, ram air intake rate, or stored compressed air capacity.

[0064] Considerations for dispersing and monitoring the dispersed particles may include requirements for countering the warming effect of anthropogenic greenhouse gases, such as the specified radiation reduction requirement, from which additional particle design considerations may be derived, such as avoiding stratospheric heating and avoiding interaction with ozone and other stratospheric and possibly tropospheric compounds. From the specified radiation reduction requirement, various dispersal considerations may be derived to suggest global dispersion patterns (spatially and temporally). Dispersal considerations further yield transportation considerations to yield flight plans and to manage the airplanes of the fleet with respect to atmospheric currents and conditions as well the evolution of the particle distribution following their dispersal.

[0065] Additional considerations include monitoring the atmospheric transport of particle batches, e.g., using markings such as trace metals, stable isotopes and / or fluorescent materials; and after dispersal, monitoring the reflectance / scattering of sunlight that the particles yield, e.g., using ground-based, air-based and / or space-based monitoring technologies. In certain embodiments, the airplanes that disperse the particles may also monitor their previous dispersal and / or optical effects such as scattering and reflectance of particles dispersed in the past. Finally, global temperatures as well as stratospheric temperatures may be monitored to detect the effects of the dispersal of particles on the temperatures (as a result of their effects on incoming radiation), and the target distribution may be adjusted accordingly (e.g., by modifying dispersal considerations). For example, direct local measurements in the troposphere may be carried out, as well as indirect indications for warming, stability and other effects in the stratosphere. In certain embodiments, the airplanes that disperse the particles may also monitor temperature throughout their flight profile, including stratospheric temperature mapping by implementing remote sensing. One or more control units may be used to support monitoring and controlling the various parameters involved.

[0066] For example, dispersal in the stratosphere may be carried out above the tropopause, possibly utilizing uprising masses of air to increase the residence duration of the particles in the stratosphere. While the average altitude of the tropopause is 36,000 feet (ca. 12 km), this altitude ranges between 25,000 feet (ca. 8km) over the poles and 60,000 feet (ca. 20km) above the equator. While in polar and temperate latitudes various types of airplanes are available forP-635226-PCdispersing the particles, dispersal at equatorial latitudes requires using dedicated or modified aircraft to achieve the required altitudes. The dispersal of the particles may be carried out by converted mid-large sized business jets (e.g., Gulfstream GV) at all latitudes, or by different types of airplanes at different latitudes.

[0067] As illustrated schematically in Figure 1C, dispersal mechanisms 130 may be adjusted to dispersion plan 100, especially with respect to types of airplanes 110 and corresponding air sources 120, determining the specifications for particle dispersal under flight conditions 135 (e.g., amounts and types of particles dispersed at various flight latitudes and altitudes). Logistic considerations 118 are further taken into account to operate the dispersal plan with the required throughput and according to the geographical dispersal requirements, with respect to the dispersal throughput of dispersal mechanisms 130.

[0068] In various embodiments, either positive pressure (pushing the powder) or negative pressure (pulling the powder) may be used to move and disperse the particles. Various feeding and dosing mechanisms maybe used, e.g., a rotary valve, a vertical screw, or other mechanisms may be used to feed and dose amounts of powder 105 released for dispersal.

[0069] As a non-limiting lab-scale example of dispersal mechanism 140 illustrated schematically in Figure 2A, a 50L hopper 145 was used to hold about 40kg of powder 105 comprising the reflective particles, which was delivered by a feeder 142 and a conveyor 150 to an air inlet 147 with filters and control valve(s) 148 to disperser 140, e.g., a Venturi disperser 140 configured to controllably release the compressed air as a flow into air surrounding the airplane, while utilizing the Venturi principle to introduce the particles delivered from the feeder into the air flow and out of the airplane for dispersal 135 of the required amounts of powder 105. A compressed air source 122 was configured to simulate bleed-air or air from intake ducts, and included multiple compressed air cylinders 122A (typically, around WOOL air per cylinder, with 25-50 cylinders corresponding to the air supply in a flight, depending on the amount of powder that is to be dispersed), delivering the compressed air through pressure regulator(s) 122B, typically including first and second stage regulators and a control valve 148 - to disperser 140. In the lab-scale experiment, dispersal unit 140 was about 5kg and 10x20x30cm3, and included a straight conduit 140A for delivering the compressed air and a powder conduit 140B connected at an angle (denoted schematically as a) to straight conduit 140A, where powder is sucked into the straight conduit via the Venturi principle. The angle a may be optimized to achieve maximal separation between the particles, in relation to the air flow speeds in straight conduit 140A and powder conduit 140B, parameters of the powder (e.g., degrees of agglomeration and stickiness), required throughput and additional considerations.P-635226-PC

[0070] Operational high-throughput dispersal mechanisms 130 may utilize bleed air or air from intake duct(s) to increase the weight efficiency of the dispersal (e.g., reduce weight, increase amount of powder dispersed per flight, reduce power requirements, etc.). For example, using bleed-air systems or other compressed air sources, dispersal mechanism 140 may be configured to disperse between 5-10 tons of particles per flight. The design of feeder 142 and hopper 145 may be adjusted accordingly, to increase throughput, reduce weight, etc. In a nonlimiting example, 5 tons of particles, having a bulk density of 0.5-0.9 kg / L require ca. 9-6 m3of net storage volume, respectively (e.g., 8 m3of net storage volume for a bulk density of 0.6 kg / L). High-throughput dispersal mechanism 140 may be configured to disperse this amount of particles within an hour’s flight at the designated altitude. It is understood that these numbers are presented by way of example only, and each may vary in further embodiments above or below the stated amounts.

[0071] Dispersal mechanism 140 may be configured with respect to, and to allow control of the deagglomeration of the particles and the way the particles are dispersed behind the aircraft. Dispersal mechanism 140 may be configured to release the powder into the air flow to deagglomerate the particles during the brief dispersal period. In various embodiments, dispersal mechanism 140 may be configured to release the powder into the air flow freely or may further comprise an impact target 141 such as bars, grids or other elements, possibly set at optimized angles to the exiting flow, to further deagglomerate particle aggregates if some still remain in the flowing dispersed powder.

[0072] In non-limiting examples, dispersal mechanism 140 may optionally comprise a thin-wire grid 141 (illustrated schematically) as impact target 141 at an external opening of Venturi disperser 140, configured to de-agglomerate the reflective particles. For example, the mesh size of wire grid 141 may be larger than the particle diameters by two orders of magnitude or more, e.g., the mesh size of wire grid 141 may be tens to hundreds of microns. Thin-wire grid 141 may be set at an optimized angle for deagglomerating particle aggregates.

[0073] Figures 2B-2E provide schematic non-limiting illustrations of feeding configurations of the powder to dispersal mechanism 140, according to some embodiments of the invention. Various embodiments of dispersal mechanism 140 comprise a powder storage 145 configured to contain and release the powder onto one or more conveyor(s) 150 which is configured to deliver the powder from powder storage 145 to disperser 140, for dispersing outside the airplane. Figures 2B-2E schematically illustrate various configurations of powder storage 145, illustrated in a simplified and non-limiting manner as one or more hoppers 145, but possibly configured as various types of containers and releasing devices, conveyor(s) 150, illustrated in a simplified and non-limiting manner as one or more linear conveyor(s) 150, with associatedP-635226-PCone or more feeder(s) 142 configured to transport the powder along respective convey or(s) 150.Dispersers 140 are illustrated in a simplified and non-limiting manner as eductors or ejectors having a powder inlet to receive the powder from conveyor(s) 150, an entry for the motive air (e.g., bleed air or air from intake ducts), and a dispersal exit for the air carrying the particles. The flow rates of air and powder, and the design of dispersers 140 (geometry and nozzle shapes) are configured to result in the required dispersal pattern 135.

[0074] In various embodiments, the configuration and parameters of the eductors (or other types of dispersers) may be adjusted to the characteristics of the available motive air (from the main air supply, e.g., compressed air) and the available suction air (entering from the surroundings and / or from the feeder(s) (see, e.g., Figure 2B). Specifically, the eductors are adjusted to the corresponding availability, pressure, density and other parameters of the motive air and of the suction air.

[0075] The shape, number and configuration of containers and hoppers of powder storage 145 may be configured to fit into the respective airplane to reach dispersal specifications, e.g., with respect to amount of powder (e.g., 3, 5, 10 or tens of tons) that is dispersed in each flight. The number and configuration of conveyor(s) 150 and dispersers 140 may be configured to achieve the required dispersal rate, e.g., 1, 5 or 10 tons of powder per hour, depending on the mission specifications, and with respect to the available amount of compressed air (e.g., 1 kg of dispersed powder per 1 scm of compressed air).

[0076] As non-limiting examples, Figure 2B illustrates schematically multiple conical hoppers 145 releasing powder to a common conveyor 150 leading a common disperser 140. It is noted that hoppers 145 may comprise various mechanisms (illustrated schematically as a rotary valve) configured to ensure uniform release of the powder onto the conveyor (e.g., ensuring full and continuous fluidization of the powder) and to prevent agglomeration and obstructions to the continuous flow of powder out of hoppers 145 throughout the dispersal operation. In another non-limiting example illustrated in Figure 2C, multiple conical hoppers 145 may be associated with multiple conveyors 150 to deliver the powder to multiple dispersers 140 to achieve the required throughput of powder dispersal and possibly to provide backup in case of malfunction of some of the units. For example, 4-10 eductors 140 may be used to reach dispersal rates of 5-10 tons / hour.

[0077] As a further non-limiting example, Figure 2D schematically illustrates elongated trough-shaped hoppers 145 feeding screw conveyor 150 as initial conveyor 150 that may deliver the powder to multiple dispersers 140 to achieve the required throughput of powder dispersal. In another non-limiting example illustrated in Figure 2E, multiple trough-shaped hoppers 145P-635226-PCwith associated screw conveyors 150 may be used to feed powder to dispersers 140, e.g., in a one-to-one configuration.

[0078] Figure 2F illustrates schematically a non-limiting example for arranging a feeding and dispersal configuration within an airplane, according to some embodiments of the invention. Hoppers 145 are illustrated having sizes fitting the fuselage and loaded containing the powder to be dispersed. Conveyors 150 move the powder from hoppers 145 to dispersers 140, which may use air supply 124 from the airplane to disperse the particles according to the required dispersal pattern 135.

[0079] Figure 2G and 2H schematically illustrate embodiments of deagglomeration mechanisms 180, according to some embodiments of the invention. For example, Figure 2G illustrates schematically a configuration of deagglomeration mechanism 180 that includes using two (or more) eductors 182, 140, with first eductor 182 receiving powder and air and deagglomerating the powder, delivering the mixture of air and deagglomerated powder to an intermediate container 184 (e.g., hopper), which may include a safety valve with a filter, and from which the air and deagglomerated powder are fed to subsequent eductor(s) 140 operating as dispersal mechanism 140, which also further deagglomerate remaining particle aggregates in the powder and disperse the powder into the atmosphere (indicated schematically by numeral 135). In some initial experimental configurations, such deagglomeration mechanisms 180 were shown to double the relative amount of particles smaller than 1pm (compared to using a single eductor, e.g., reaching 70%) and ensuring that at least 95% of the particles are smaller than 2pm.

[0080] In another example, Figure 2H illustrates schematically a configuration of deagglomeration mechanism 180 that includes using two (or more) eductors 182, 140, with first eductor(s) 182 receiving air and a mixture of powder and air and deagglomerating the powder, delivering the mixture of air and deagglomerated powder through particle classifier 186 which separates submicron particles from larger, agglomerated particles that are further delivered to subsequent eductor(s) 140 for further deagglomeration and dispersal. Such deagglomeration mechanism 180 was found to be effective for dispersing powder that initially contains two main size populations - one at the required submicron distribution (individual separated particles), and another measuring few to tens of microns (agglomerated particles). The separation in particle classifier 186 may be based on the different turning radii of aerodynamically small vs large particles therethrough (due to the different Stokes number of the two populations of particles) - enabling the removal of smaller particles before the end of the classifier, and delivering larger particles through the end of the tube to the subsequent eductor(s) 140. Both the initially separated submicron particles (denoted schematically 135A) and the later de-P-635226-PCagglomerated particles (denoted schematically 135B) are dispersed into the atmosphere (separately or after combining the flows). In some embodiments, more than two stages of eductors may be used to further increase the efficiency of deagglomeration mechanism 180.

[0081] Figure 21 and 2J illustrate experimental results concerning particle size distributions using a single eductor compared to using two eductors 182, 140 with intermediate container 184, respectively, according to some embodiments of the invention. Figure 21 indicates the presence of a significant portion of particle aggregates (peak around 100pm), in addition to the main distribution of submicronic particles (peak around 0.7pm). The particle aggregates result from a degree of stickiness of the particles in some embodiments, which may otherwise be resolved by applied coatings as disclosed herein. However, when using two eductors 182, 140 with intermediate container 184 as illustrated schematically in Figure 2G, the PSD changes to that illustrated in Figure 2J to include only a single peak (around 0.6pm), including mainly single particles and only a minimal amount of small particle aggregates (>95% of the particles are under 2pm), without the larger aggregates indicated in Figure 21. These experimental results thus prove the efficiency of the de-agglomeration unit provided in Figure 2G, with the arrangement presented in Figure 2H providing comparable or better de-agglomeration results.

[0082] Advantageously, various embodiments of disclosed particle configurations and / or of de-agglomeration mechanisms 180 solve the problem of agglomeration of the sub-micronic particles and enable an efficient dispersal of disclosed sub-micronic particles into the stratosphere.

[0083] Figures 3A and 3B illustrate an experimental example of a disperser with a nonlimiting example for a pattern of dispersal of particles, and an example for a particle size distribution in a free jet, according to some embodiments of the invention. Figure 3A illustrates an experimental example of disperser 140 with a non-limiting example for a pattern of dispersal 135 of particles, according to some embodiments of the invention. Figure 3B provides an example for a particle size distribution in a free jet, according to some embodiments of the invention. The graph characterizes the volume density (distribution and cumulative) of the dispersed cloud, by particle size.

[0084] Figure 4 illustrates an experimental structure and application of aerial dispersal system 130, according to some embodiments of the invention. In the non-limiting experimental setting illustrated schematically in Figure 4, aerial dispersal system 130 comprises compressed air source 112A that simulates the compressed air inlet of the airplane, pressure regulators 122B configured to adjust the compressed air pressure to the requirements for dispersing the powder, powder eductor 140 and a feeding and releasing mechanism 140A that receive the powder from eductor 140 and release the powder as the dispersed stream of particles 135.P-635226-PC

[0085] In some embodiments, aerial dispersal system 130 may be configured and utilized to disperse particles into other parts of the atmosphere, other than into the stratosphere, and / or for purposes other than SAI, for example, aerial dispersal system 130 may be configured and used to disperse particles as tracers for monitoring weather conditions in the atmosphere, to disperse particles within air conditioned spaces to trace and monitor air exchange in closed spaces, or for other uses.

[0086] In various embodiments, dispersal mechanism 140 may further comprise one or more sensor(s) configured to monitor the particles immediately after their dispersal, e.g., to detect the amount and parameters of dispersed particles, e.g., to measure their size distribution.

[0087] Figures 5A-5D provide non-limiting examples for particle size distributions upon dispersal, according to some embodiments of the invention. Figures 5A and 5B provide a particle size distribution (PSD) measured in a spray tunnel indoor facility (simulating dispersal mechanism 140 and measuring the PSD using sensors, e.g., as in Figure 4). The PSD is shown both as the mass density distribution and as the cumulative mass of particles with increasing diameter. Figures 5A and 5B include data derived from two measurement methods - laser diffraction imaging and optical particle spectrometry (OPS). Both measurements indicate that the large majority of the dispersed particles are smaller than 1pm, and at most 5% of the dispersed particles are larger than 10pm, representing scarce agglomerates of the 0.5pm particles. Both instruments indicate that the larger portion of the PSD is centered around 0.4-0.5pm, with a smaller additional spread around 2-3pm due to agglomeration. Figure 5C illustrates the effect of the dispersal rate on the PSD, as measured with the OPS. Mass density distributions and cumulative mass are provided for three dispersal rates, 10, 20 and 50 kg / hr of powder, with the same nozzle, which are approximately equivalent to 35, 70 and 175 kg powder per 100 scm of compressed air, shown as the solid, dotted and dashed lines, respectively. It is noted that at the lowest flow rate, approximately 85% of the mass is dispersed as submicron particles, while higher flow rates increase the fraction of particle mass dispersed as larger agglomerates. In various embodiments, nozzle configurations may be adjusted to achieve the required level of deagglomeration at given powder flow rates. Figure 5D illustrates outdoor measurement of the PSD using dispersal from a moving vehicle, measured using an OPS mounted on another vehicle, as an intermediate step to directly measuring the PSD in aircraft plumes. Figure 5D indicates that most particles are de-agglomerated, with measured diameters around 0.5pm, with the median being 0.6pm and dw (90thpercentile) below 2pm indicating efficient deagglomeration even with a 1: 1: powder to air mass ratio and high air flow rates.

[0088] The spherical particles may be dispersed as a powder from airplanes across the stratosphere, to yield a specified stratospheric distribution and reflect incoming sunlightP-635226-PC(without significantly absorbing outgoing infrared radiation) - to reduce incoming radiation and mitigate the effects of global warming. Certain embodiments comprise the dispersal of the spherical particles of the powder in atmospheric air, e.g., in the stratosphere across all latitudes, or, in some embodiments or due to atmospheric circulation - in specific regions or belts. The spherical particles may have diameters ranging between 0.1 pm and 1 pm to ensure safety (lower size limit considerations) and long residence time in the stratosphere (upper size limit considerations). In various embodiments, the spherical particles may have diameters ranging between 0.1 -1pm.

[0089] In various embodiments, the spherical particles may comprise spherical amorphous silica particles produced using sol -gel processes such as the Stober sol -gel process, which yields particles with uniform sizes. It is noted that, while many types of silica may be produced using various processes, the inventors have found that sol-gel processes (e.g., the Stober sol-gel process) yield particles with the density and uniform sizes required for the spherical particles. Additionally, the Stober sol-gel process yields particles with a non-porous surface area, which is further advantageous with respect to the inertness of the spherical particles. The spherical particles may have a surface area in the order of a few m2 / g (for diameters of about 0.5 microns) and a low porosity - indicating the compactness and tight spherical shape of the spherical particles and significantly contributing to their inertness by providing little surface area for interaction. Typical ranges for the surface area of the spherical particles may be between 1-10m2 / g, between 5-20m2 / g or within any subrange thereof for the surface area. In non-limiting examples, the surface area of the spherical particles was measured to be around 5m2 / g. Typical ranges for the porosity of the spherical particles may be between 0.01-0. lcm3 / g or within any subrange thereof for the pore volume; and between 50-300A or within any subrange thereof for the pore size. In non-limiting examples, the pore volume of the spherical particles was measured to be between 0.01-0.02cm3 / gm and the pore diameter of the spherical particles was measured to be between 100-150A by different types of measures. Modification of the parameters of the Stober sol-gel process, or changing the production process may change these values, e.g., adjusting the parameters of the Stober sol-gel process was shown to decrease pore size by exposure to higher temperatures.

[0090] In various embodiments, the spherical particles may comprise spherical amorphous calcium carbonate particles, depending on the details of their production process.

[0091] It is noted that the spherical particles may comprise nearly-spherical particles, e.g., ellipsoid particles, with axes diverging from each other by at most 10% or 20%, or intermediate values. As used herein, the term “substantially spherical” refers to particles that, while possibly not perfectly spherical at the microscopic level, possess an overall morphology that is visuallyP-635226-PCand functionally spherical when viewed in electron micrographs or when characterized by particle aspect ratio. In some embodiments, substantially spherical particles exhibit aspect ratios (ratio of longest to shortest dimension) of less than about 1.2, or less than about 1.1. Minor surface irregularities, dimples, or deviations from perfect roundness that do not materially affect particle behavior, properties, or light-scattering characteristics are encompassed by the term “substantially spherical.”

[0092] In various embodiments, spherical particles may comprise spherical core-shell particles, with cores comprising mineral, dielectric and / or organic grains such as at least one of: CaCCh (e.g., crystalline or amorphous calcium carbonate, ACC, stabilized using various methods and / or additives), calcium alginate and maltodextrin, as well as possibly other calcium compounds (e.g., CaO, CaOH, Ca(OH)2), possibly nanodiamonds (when incorporated in a silica core, which may be porous) or other biosafe dielectric materials (preferably ones that are abundantly formed in natural processes, such as some minerals), and shells that may comprise amorphous silica produced using the Stober sol-gel process. In various embodiments, particle and core materials may be selected according to their safety and inertness, to ensure compliance with the criteria defined herein. Cores may be selected to have better optical properties compared with amorphous silica, e.g., lower absorption of infrared (IR) radiation and / or higher scattering effect per weight (reflectivity / particle mass). Cores may be selected to be safe and / or stable under UV radiation, with additional protection from the environment provided by shells.

[0093] For example, core-shell spherical particles may comprise precipitated calcium carbonate cores with shells grown upon cores using sol-gel processes such as the Stober or other sol-gel processes. In certain embodiments, shells may be a few tens of nm thick, e.g., between 10-20nm, 10-30nm or 10-50nm thick, to ensure chemical inertness of core-shell spherical particles. In various embodiments involving calcium carbonate in particle cores and / or shells, production methods based on mixing calcium hydroxide slurry (Ca(OH)2) with CO2 may be tuned to form either crystalline or amorphous calcium carbonate, ACC, which may accumulate, e.g., as spheres. The main parameters to control the process are mixing speed, concentration, carbon dioxide bubbling rate and temperature - to reach cores at the required dimensions for coating by shells.

[0094] In various embodiments, alternative or additional production methods for spherical calcium carbonate particles or their cores include solution precipitation methods, e.g., using a controlled reaction between soluble calcium nitrate and sodium carbonate, optionally with the addition of carboxymethylcellulose, where parameters and additives may be controlled to affect the particle size and morphology (e.g., the purity and reproducibility of any crystalline structures). Alternatives to carboxymethylcellulose include Sodium Tripolyphosphate ,P-635226-PCPoly(sodium styrene sulfonate) or Polyoxyethylene (20) sorbitan monolaurate (Tween20 or tween 80), Ethylene glycol or glycerol, Hexadecyltrimethylammonium bromide (CTAB), Acrylic acid, sodium stearate, sodium stearoyl lactate, poly ethylene glycol, sodium casein, phosphate esters or sulfonated polystyrene or Gelatin, Poly (acrylic acid sodium salt), Ethylenediaminetetraacetic Acid, Stearic acid, or any combination of them.

[0095] In various embodiments, calcium carbonate cores may be amorphous (ACC) and / or spherical, depending on the details of their production process. Amorphic calcium carbonate may be stabilized using various methods and / or additives. In various embodiments, the cores may comprise calcium sulfate dihydrate.

[0096] In various embodiments, the silica or calcium carbonate cores may be coated with inert hydrophobic (non-polar) coatings by forming hydrophobic coatings over shells, or by direct coating by hydrophobic coatings directly on the calcium carbonate. The hydrophobic coating is non-polar in that it has practically no permanent dipole as well as low polarizability (i.e., it does not have regions of positive and negative electrical charge permanently nor induced under the influence of external fields or internal fluctuations. In certain embodiments, the coating 130 may be functionalized (modified) with UV-resistant short-chain silane molecules adapted for stability under stratospheric conditions. Such surface functionalization provides enhanced resistance to degradation from ultraviolet radiation. The silane molecules may be substantially free of carbon-carbon bonds and instead comprise primarily carbon-silicon bonds, which are less susceptible to UV-induced bond cleavage. As a result, the coating maintains its integrity and performance when exposed to high-intensity UV radiation encountered in the atmosphere, thereby improving the long-term durability and stability of the particles under such environmental conditions. Examples of such hydrophobic coatings may comprise one or more of tetra-ethoxy -silane, tetra-methoxy-silane, tri methyl methoxy silane, dimethyl dimethoxy silane, monomethyl trimethoxy silane, tri methyl ethoxy silane, dimethyl diethoxy silane, monomethyl triethoxy silane, trimethylsilane (TMS), methyltrimethoxysilane (MTMS) and / or combinations thereof. In various embodiments, hydrophobic coatings may comprise hexamethyldisilazane (HMDS, also termed bis(trimethylsilyl)amine, which are trimethylsilyl derivatives of ammonia), derivatives thereof, or other silanized or analogous materials with short carbon chains attached to the silicon atoms. Hydrophobic particles minimize interactions with liquid water and ice, reducing cloud condensation, and ice nucleation. Embodiments of the present technology describe the coating being formed over the shell. However, in further embodiments, the coating and the shell may be formed together as a unitary layer over the core. In such an embodiment, the combined shell and coating may haveP-635226-PCany or all of the properties of the shell described herein, and any or all of the properties of the coating described herein.

[0097] In some embodiments, silanization during application of coating may be carried out in an acidic environment (e.g., using sulfuric acid H2SO4 and / or other acids) together with oxidizer(s) (e.g., hydrogen peroxide H2O2 and / or other oxidizers) - which activate the surface of spherical particles to bind the respective coating material. The process may be conducted in a solution or in the gas phase.

[0098] Hydrophobic (non-polar) coatings may be made thick enough to prevent contact between calcium carbonate cores and the environment and prevent chemical interactions and nucleation, due to hydrophobic coatings. Certain embodiments comprise spherical particles that are composed of cores which comprise, or consist of, at least one of: amorphous silica, CaCCh. calcium alginate and maltodextrin, dolomite CaMg(C0a)2, and thick hydrophobic coatings that prevent agglomeration and improve dispersal of particles.

[0099] In various embodiments, spherical core-shell particles may comprise calcium carbonate cores with diameters about 300-400 nanometers, sol -gel amorphous silica shells that may have an optimized thickness (e.g., any of lOnm, 20nm, 40nm, 50nm, 70nm, lOOnm, intermediate values, or within subranges between these values), and optionally hydrophobic coating. Functionally, and advantageously for core-shell particles - calcium carbonate cores have very low IR absorption; amorphous silica shells may be included as shells to prevent atmospheric interactions with calcium carbonate cores, and coating may be applied onto the particles to prevent agglomeration, nucleation and wetting of liquids (e.g., water / sulfate vapors) or ice, and to prevent uptake of stratospheric trace species - further enhancing the inertness of particles. It is noted that coating may be configured to be hydrophobic / non-polar, and may further comprise functional groups and / or steric structures that prevent the interactions listed above, and ensure the inertness of the particles.

[0100] Chemical link between calcium carbonate cores and amorphous silica shells may be achieved through hydroxyl groups on the surface of calcium carbonate cores, e.g., formed during the production process or during further heating that modifies surface calcium carbonate molecules into calcium hydroxyl molecules, as taught, e.g., by Lee at al. 2019 (Effect of surface modification of C aCCh nanoparticles by a silane coupling agent methyltrimethoxysilane on the stability of foam and emulsion, Journal of Industrial and Engineering Chemistry, 74: 63-70). Coating calcium carbonate cores with amorphous silica shells 125 may be carried out through processes similar to the sol-gel processes disclosed herein. In some embodiments, amorphous calcium carbonate (ACC) may be used to fabricate calcium carbonate cores - yielding spherical calcium carbonate cores on which amorphous silica shells may be grown.P-635226-PC

[0101] In various embodiments, the spherical particles may comprise a hydrophobic (nonpolar) surface material that is resistant to ultraviolet (UV) radiation and is attached to the surfaces of the particles. The hydrophobic surface material may be selected to be safe and inert. For example, the hydrophobic surface material may comprise a silane with at least one methoxy group which binds to hydroxyl groups at the surface of the spherical particles, the silane consisting of at least one of: trimethylmethoxysilane, dimethylydimethoxysilane and methyltrimethoxy silane, tri methyl ethoxy silane, dimethyl diethoxy silane, monomethyl triethoxy silane, hexamethyldisilazane, derivatives thereof, other silanized or analogous materials with short carbon chains attached to the silicon atoms, and / or combinations thereof. The short (single carbon) side chains assure stability of the hydrophobic coating against prevalent strong UV radiation in the stratosphere, as silanes with longer carbon chains were shown to disintegrate under intense UV radiation. In various embodiments, the hydrophobic surface material may be made of different hydrophobic surface materials such as HMDS, or analogous materials with short carbon chains attached to the silicon atoms.

[0102] In cases where a particle comprises a calcium carbonate core, hydrophobic coatings may be made thick enough to prevent contact between cores and the environment and prevent chemical interactions and nucleation, due to the hydrophobic coatings. Thickly coated calcium carbonate cores may be considered core-shell spherical particles, with the shells provided by the thick hydrophobic coatings.

[0103] In some embodiments, the powder may comprise one or more anti -caking agents or flow-enhancing additives. Additives may include silica nanoparticles, surface coatings, surfactants, hydrophobic agents, or moisture -reduction compounds that reduce cohesive forces within powder. Additives may improve stability during storage, enhance fluidization or aeration, and reduce the formation of agglomerates during conveying and dispersal. The type and concentration of additives may be selected based on particle composition, particle size distribution, environmental humidity, or desired dispersal characteristics.

[0104] In various embodiments, spherical particles may further include spacers such as nanometric particles that have diameters ranging between 1 Onm and 5 Onm, which are dry mixed with spherical particles to prevent agglomeration thereof. For example, nanometric particles may comprise 10-30nm nanometer particles of fumed silica and / or 10-50nm nanometer particles of amorphous silica produced by various methods, e.g., the Stober sol-gel process, which may be coated to provide the inertness required for SRM. Spacer particles 150 also help prevent agglomeration of particles 100. To prevent agglomeration and enable maximum dispersion, particles of different sizes between 200 nm and 800 run can also be combined in varying proportions. It is noted that the sizes and amounts of nanometric particles may beP-635226-PCconfigured to keep the surface area of the powder below 10 m2 / g, or below 20 m2 / g, to maintain dispersibility without substantially increasing the potential chemical impacts. The tradeoff between dispersibility (and a possible need to de-agglomerate the powder upon dispersion) and the configuration of the particles’ surfaces and spacers may be optimized with respect to the specific type of particles used and the specific dispersion systems (type of airplane and type of dispersal mechanism). It is emphasized that the production and dispersal processes may be configured to ensure that spacers stay attached to particles and do not detach from them, e.g., for efficiency and safety reasons as disclosed herein. The fixed attachment may be achieved in physical and / or chemical methods, to ensure the attachment of spacers to particles throughout their residence period in the atmosphere. Nanometric spacer particles may comprise various materials, such as amorphous silica or other types of silica, e.g., fused silica, fumed silica, precipitated silica, or of other compatible nanometric materials. In various embodiments, spacers may be coated, e.g., by hydrophobic and / or by hydrophilic coatings. In various embodiments, spacers may be configured to have similar surface properties as particles, as disclosed herein.

[0105] Monitoring the spherical particles during production, transportation and dispersal may be carried out using various types of markers. For example the tagging may comprise at least one of: metal traces comprising at least one of Ca, Zn, Sr, Fe, Cu, Al, at amounts between a few ppm and a few tens of ppm in mass, stable isotopes selected from at least one of:29Si,13C,2H,18O,42Ca,43Ca,44Ca,46Ca, and / or luminescent transition metal cations such as Eu complexes and / or strontium aluminates as a fluorescent material.

[0106] Dispersal mechanism 140 may be used to disperse any type of particles, possibly with adjustments with respect to size, type and level of agglomeration of the respective particles. It is noted however, that the dispersal throughput of dispersal mechanisms 130 partly depends on the type of dispersed particles, e.g., particles that are less agglomerated may be more easily dispersed, requiring less air, power and / or time for dispersal. For example, coating of particles and / or adding nanometric spacers between the particles may reduce the required amount of air for dispersal, reduce the dispersal duration and / or increase the dispersal throughput. The configuration of thin-wire grid 141 may also be adjusted to the type of particles and may increase or reduce the throughput of dispersal mechanism 140 depending on its configuration.

[0107] Supply chain management, the dispersal operation, as well as safety and atmospheric effects may be monitored using tracers and markings (or attributions) of the particles, such as trace metals, stable isotopes and / or fluorescent elements included in the amorphous silica material (and / or mineral core material in amorphous silica coated core-shell particles). For example, markings (or attributions) may be used for monitoring production andP-635226-PCdispersal of the particles, while tracers may be used for experimental monitoring of effects, e.g., for validation of the aerosol layer structure. Tracers and / or markings (or attributions) may be provided in various parts of the particles, such as within the particle itself and / or its coating, and / or in cores and / or shells of particles in core-shell configurations, as well as optionally in coatings and / or nanoparticle spacers. Different combinations of types and amounts of tracers and markings (or attributions) may be used to fingerprint different batches of particles.

[0108] It is noted that any of the materials and their concentrations used for marking (e.g., as tracers and / or markings / attributions) may be detected and used as naturally occurring materials, as materials introduced during production and / or as intentionally introduced materials. Material quantities may be measured and / or augmented during production for the purpose of monitoring the logistics, transportation, dispersal and post-dispersal distribution of the particles, as disclosed herein.

[0109] Tracers and / or markings (or attributions) may be used for different purposes, e.g., tracers may be used to validate and monitor physical aspects, such as the distribution of particles throughout the stratosphere, while markings (or attributions) may be used to monitor logistic aspects such as production, delivery and dispersal. Tracers and / or markings (or attributions) may be used in combinations that allow monitoring specific batches of produced and / or dispersed powders, and relate them to their sources and specific dispersal operations, e.g., for monitoring, quality verification, etc. Different combinations of tracers and / or markings (or attributions) may be used to uniquely identify specific batches and / or specific dispersal operations.

[0110] In various embodiments, tracers and / or markings (or attributions) may be used to define international standards for dispersing (and monitoring) particles, to ensure aligning multiple dispersal operations carried out by multiple providers at multiple latitudes and altitudes, relating to many countries and possibly multiple airplane fleets.

[0111] Figure 6 is a high-level flowchart illustrating a method 200 of dispersing reflective particles from airplanes out into the stratosphere using energy and compressed air provided by the airplane (stage 202), according to some embodiments of the invention. The method stages may be carried out with respect to aerial dispersal system 130 described above, which may optionally be configured to implement method 200. Method 200 may comprise the following stages, irrespective of their order.

[0112] Method 200 may comprise conveying the powder to be fed for dispersal (stage 210), optionally by negative pressure (stage 212), feeding the powder by gravity or by negative pressure while dosing, sensing and controlling the feed (stage 222), and deagglomerating the powder, e.g., by negative pressure and / or by impinging the powder onto a target (stage 230).P-635226-PC

[0113] In some embodiments, method 200 comprises feeding the powder by gravity and fluidizing the powder prior to the feeding (stage 224).

[0114] Method 200 may further comprise monitoring the reflective particles immediately after their dispersal (stage 240), e.g., to detect the PSD and / or throughput of released particles.

[0115] In some embodiments, aerial dispersal system 130 may further comprise mechanisms configured to enhance flow performance, break down agglomerates, and improve uniformity of particle dispersion under a range of operating conditions. Such mechanisms may be incorporated upstream of dispersal mechanism 140, within dispersal mechanism 140, or downstream of dispersal orifice structures.

[0116] In certain embodiments, compressed air delivered to dispersal mechanism 140 may be modulated or pulsed. Pulsed flow may generate transient acceleration profiles and fluctuating pressure gradients that promote particle deagglomeration. Flow pulsing may also reduce the total volume of compressed air required for effective dispersion of powder 105. Pulsing may occur through active valve control, rotary shutter elements, oscillating nozzles, or cyclic ducting geometries. Pulse frequency, amplitude, and duration may be selected or varied based on particle size, agglomerate strength, target dispersal rate, or available onboard energy.

[0117] In some embodiments, deagglomeration mechanisms may be optimized for submicron particle agglomerates by establishing localized regions of high turbulent dissipation rate, fine-scale turbulent eddy formation, flow acceleration, or particle residence-time concentration. Regions of intense turbulent shear may be generated using internal baffles, mixing vanes, step changes in flow channel geometry, or converging-diverging duct elements configured to alter particle trajectories and increase the frequency of particle-to-particle and particle-to-surface collisions. These effects may be particularly advantageous for powders comprising submicron particles or particle clusters exhibiting strong cohesive forces.

[0118] In certain embodiments, particle trajectories may be tailored by manipulating local air velocity fields to control the Stokes number of powder 105 aggregates within deagglomeration or dispersal flow paths. Internal structures such as geometrical protrusions, corrugations, turns, bends, or flow-combining junctions may induce changes in particle direction or velocity relative to air flow, thereby increasing exposure to shear layers and collision regions. These geometrical flow-control features may increase turbulence intensity, increase drag-force stresses from slip-velocities, improve mixing uniformity, and enhance deagglomeration efficiency.

[0119] In some embodiments, deagglomeration may be achieved or enhanced by applying pressure gradients and / or rapid acceleration transitions. For example, compressed air and entrained particles may be directed through regions that generate shock waves or high-P-635226-PCgradient flow acceleration. Shock-induced pressure differences may separate agglomerated particles by overcoming interparticle adhesion forces. Pressure gradient deagglomeration may be combined with venturi ducts, eductors, flow constriction zones, or acoustic excitation regions to achieve improved performance.

[0120] In certain embodiments, relatively large powder agglomerates may be broken down prior to conveying or dispersal using a milling mechanism. Milling mechanisms may include rotary impactors, screens, grinders, crushing elements, or shear surfaces configured to fragment agglomerates into smaller particles suitable for entrainment and dispersal. Milling may be performed continuously or intermittently, and may be integrated within feeder 142, conveying mechanism 150, or within a staging chamber upstream of dispersal mechanism 140.

[0121] In some embodiments, aerial dispersal system 130 may further comprise particle charging mechanisms configured to generate or maintain electric charge on powder 105 during conveying, deagglomeration, or dispersal. Electric charges may reduce particle agglomeration by increasing electrostatic repulsion between particles, thereby improving uniformity of dispersion and enhancing particle separation in the atmosphere. Particle charging mechanisms may operate prior to dispersal, within dispersal mechanism 140, ordownstream of the dispersal orifice.

[0122] In some embodiments, the motion of powder 105 against interior surfaces of dispersal mechanism 140 may generate electric charge by triboelectric effect. Compressed air may accelerate powder 105 through conduits, ducts, and flow passages, causing friction between particles and between particles and interior wall surfaces. These frictional interactions may generate electric charge and maintain particle separation by electrostatic repulsion.

[0123] In certain embodiments, dedicated triboelectric charging regions may be provided within dispersal mechanism 140. Such regions may include interior surfaces comprising materials selected to enhance triboelectric charge development, such as polymers, ceramics, or conductive or semi-conductive coatings configured to maintain or transfer charge to powder 105. The triboelectric charging region may have internal geometries configured to increase frictional interaction, including bends, constrictions, grooves, protrusions, or extended conveyance pathlength.

[0124] In some embodiments, particles 102 may be electrically charged by corona discharge. Corona discharge may be generated by elevating the electric field intensity around one or more electrodes positioned within dispersal mechanism 140 or within a charging chamber upstream of dispersal. Electrodes may be configured to generate ions in the surrounding gas stream, which may impart charge to powder 105 through ion-particle collisionsP-635226-PCor ion adsorption. Electrode geometry may include wires, needles, plates, or rods positioned to maximize ionization efficiency while maintaining acceptable airflow resistance.

[0125] In certain embodiments, an electric field may be established across powder 105 using one or more induction electrodes. Powder 105 passing through the electric field may acquire electric charge through polarization and subsequent charge separation, even without direct contact with the electrode structures. Electrode placement, voltage potential, and spacing may be selected to optimize the induction field strength and direction while allowing powder 105 to pass through the charging zone without obstruction.

[0126] In some embodiments, powder 105 may be charged by mixing the particles with ionized air. Ionized air may be generated using an ionizing element, including but not limited to corona sources, plasma sources, ultraviolet emitters, ionizing radiation sources, or high-voltage grids configured to ionize compressed air upstream of dispersal mechanism 140. Ionized air streams may impart charge to powder 105 through convection and mixing mechanisms and may be combined with triboelectric or inductive charging systems to enhance charge stability.

[0127] In certain embodiments, high-shear turbulent flow regions within dispersal mechanism 140 may generate localized electric charge on powder 105. Rapid differential motion between particles and bulk air flow may cause for example triboelectric charge development, particularly in regions of intense shear, fine-scale turbulent eddy formation, or elevated dissipation rates. Such charging phenomena may be amplified by venturi ducts, constrictions, or eductors operating at high Mach numbers or Reynolds numbers.

[0128] In some embodiments, particle charging may occur downstream of the dispersal orifice or after powder 105 exits the aerial platform. One or more charging components may be positioned in the wake or exhaust flow behind the aerial platform and may be configured to add electric charge to powder 105 during dispersal. Such components may include post-dispersal electrodes, ionization grids, or aerodynamic ducting configured to expose the dispersed particles to charged airflow regions. Post-dispersal charging may sustain particle separation in the atmosphere and enhance plume stability.

[0129] In some embodiments, aerial dispersal system 130 may further comprise structural, safety, and aerodynamic enhancements configured to improve system integration, airflow efficiency, powder management, and operational reliability. These enhancements may address powder restraint, purge mechanisms, aerodynamic energy recovery, fuselage modifications, powder storage configuration, and containerization fortransport and installation.

[0130] In some embodiments, aerial dispersal system 130 may include one or more restraints configured to mitigate against spontaneous escape of powder 105 from the aerialP-635226-PCplatform. The one or more restraints may comprise seals, valves, gasketing structures, airlocks, containment ducts, or pressure-gradient interfaces configured to control powder flow and prevent unintended release. Restraint systems may be positioned at interfaces between hopper regions, conveying mechanisms, and dispersal mechanism 140, and may function during pressurization transients, vibrations, or sudden attitude changes.

[0131] In certain embodiments, aerial dispersal system 130 may comprise a purge mechanism configured to dislodge or remove powder 105 that becomes adhered to surfaces of feeder 142, conveying mechanism 150, or dispersal mechanism 140. Purge mechanisms may generate localized fluid pulses, reverse airflow cycles, vibration bursts, mechanical agitation, or sweeping gas streams to clear powder from internal surfaces.

[0132] In some embodiments, purge mechanisms may operate using compressed air supplied through dedicated purge channels, purge valves, or purge-intake manifolds. Compressed air purge may remove powder deposits prior to dispersal shutdown, during maintenance cycles, or during flight. Purge air may be reversible, pulsed, or modulated to optimize cleaning effectiveness while minimizing airflow disruption.

[0133] Purge operations may be supplemented or performed using mechanical structures configured to dislodge powder 105 adhered to interior surfaces of feeder 142, conveying mechanism 150, dispersal mechanism 140, or associated conduits. Such mechanical structures may include, for example, external vibration actuators or wall-mounted vibration pads configured to transmit oscillatory motion through system housings; pneumatic or spring-loaded impact knockers positioned to deliver mechanical tapping forces to chamber walls; internal agitators, including rotating paddles, flexible scraper elements, or brush surfaces configured to contact or disturb powder deposits; and deformable or oscillating wall segments configured to flex during operation to break adhesion between powder 105 and internal surfaces. These mechanical dislodgement structures may operate continuously or intermittently, and may be used alone or in combination with compressed-air purge systems to maintain clear flow pathways, reduce buildup, and improve dispersal uniformity.

[0134] In some embodiments, aerial dispersal system 130 may be configured to direct outside air through dispersal mechanism 140 with minimized aerodynamic drag. Air inlets, ducts, or compression elements may be shaped or dimensioned to reduce inlet pressure losses and enhance laminar or controlled turbulent flow.

[0135] In some embodiments, aerodynamic drag associated with ram-air flow into dispersal mechanism 140 may be minimized while still providing sufficient turbulent energy to deagglomerate powder 105. Ram-air mass flow rate, duct cross-section, and internal flow geometry may be selected to achieve a threshold required turbulence intensity and shear levelP-635226-PCnecessary for agglomerate breakup, while minimizing drag forces on the aerial platform. By adjusting inlet cross-sectional area, venturi throat dimensions, flow acceleration profile, and discharge velocity, the system may deliver the minimum ram-air volume required to achieve the desired degree of particle separation. Control logic may regulate ram-air flow in response to operational parameters, including aircraft airspeed, altitude, attitude relative to motion, and desired dispersal rate, to ensure that turbulent deagglomeration is maintained at performance targets while minimizing aerodynamic penalties. In this manner, the system may continuously balance particle deagglomeration needs with drag considerations during flight.

[0136] In certain embodiments, thrust may be generated or increased by discharge of compressed air and dispersed particles from the aerial platform. This aerodynamic momentum recovery or addition may occur when discharge flow is directed rearward or partially rearward relative to aircraft motion, allowing momentum from entrained air to contribute to net platform propulsion if onboard energy is added to the system, and for momentum losses from the inlet or dispersal system to be minimized by recovery before or within the orifices or exhaust. Directional control surfaces, discharge nozzles, or thrust-vectoring elements may be configured to control exit flow angle or discharge velocity to optimize drag recovery and thrust efficiency.

[0137] In some embodiments, unused fuel-tank volume may be repurposed to store powder 105. Fuel-tank enclosures may be adapted or partitioned to incorporate internal powderstorage features while maintaining required fuel-handling capabilities. Powder storage channels or sub-compartments may be incorporated into fuel-tank structures without compromising structural integrity, balance, or safety. Tank regions may be lined or coated to prevent chemical interaction between powder 105 and fuel vapor or liquid fuel residues.

[0138] In certain embodiments, the fuselage of the aerial platform may be modified to accommodate aerial dispersal system 130 within a partially pressurized or unpressurized cabin region. Reduced pressure or unpressurized configurations may reduce cabin structural weight or energy requirements, and may reduce or eliminate the need to provide pressurization bleed air for dispersal operations. The platform may include isolation bulkheads, environmental seals, or structural supports configured to allow safe operation in either cabin pressure mode.

[0139] In some embodiments, aerial dispersal system 130 may be integrated into one or more Unit Load Device (ULD) containers configured for aircraft loading, delivery, and unloading. ULD containers may house feeder 142, conveying mechanism 150, dispersal mechanism 140, sensing components, and control subsystems. Such containerized architecture may allow rapid installation, removal, maintenance, or exchange of system modules. ULD containers may be dimensioned according to aircraft cargo-loading standards and may includeP-635226-PCinternal reinforcement structures, isolation mounts, or shock absorbers to protect components during flight operations.

[0140] In some embodiments, aerial dispersal system 130 may further comprise multiple hoppers configured to store different batches or types of powder 105. The multiple hopper configuration may allow the system to selectively disperse powder from one hopper at a time, or from any combination of hoppers, during flight. Powder may be routed to conveying mechanism 150 or directly to dispersal mechanism 140 through a switching mechanism configured to connect or isolate individual hoppers from the dispersal pathway. The switching mechanism may comprise valves, diverter gates, rotary feeders, or manifold structures adapted to independently control powder flow from each hopper.

[0141] In certain embodiments, each hopper may store batches of powder 105 having different internal markers. Such markers are described in detail in co-pending PCT Patent Application No. PCT / IL2025 / 050999 in the name of Stardust Labs Ltd, which application is incorporated by reference herein in its entirety. However, in general, particles may include metal or elements in trace amounts, such as a few to a few hundred parts-per-million, which may be introduced intentionally or unintentionally (and characterized) during production, e.g., from intended accidental contaminants with which particles come into contact during production, and are typically uniform within each powder batch. For example, the metal traces may comprise at least one of Ca, Zn, Sr, Fe, Cu, Al, K, Mg, Ti, Zr, Bi, Sn, Mo, Mn, at trace amounts between a few ppm and a few hundreds of ppm. It is noted that these trace amounts are very small and do not change the safety and inertness of particles or their optical properties. It is further noted that trace metals may be present in either or both cores and / or shells in coreshell particles. In some embodiments, trace metals may be present in hydrophobic surface material. Different types or amounts of trace metals may be present in the particles, enabling different identifiers, or signatures, for different batches of particles powders. These identifiers are explained in greater detail below.

[0142] In another example, particles may comprise stable isotopes selected from at least one of: 29Si, 13C, 2H and 180 (in place of or additionally to the trace metals) and / or any of the stable calcium isotopes 42Ca, 43 Ca, 44Ca, 46Ca (for particles that include calcium, such as core-shell particles with calcium carbonate cores). It is noted that the types and amounts of the stable isotopes may be selected and included so as not to change the safety and inertness of particles. It is further noted that the stable isotopes may be present in either or both cores and / or shells in core-shell particles. In some embodiments, stable isotopes may be present in hydrophobic surface material. Different types or amounts of isotopes may be present in the particles, enabling different identifiers, or signatures, for different batches of particles powders.P-635226-PCThese identifiers are explained in greater detail below. It is noted that the isotopes may be introduced artificially into particles, or may occur naturally, or incorporated during the production of particles, and measured for marking purposes.

[0143] In yet another example, particles may comprise added fluorescent materials such as luminescent transition metal cations, e.g., europium (Eu) complexes, strontium aluminates (e.g., SrA12O4) or combinations thereof (e.g., Eu:SrA12O4) in trace amounts (e.g., under 0. lwt%) as markers, in place of or in addition to trace metals and / or stable isotopes. Fluorescent materials may be used at low quantities, e.g., a few ppm and may be used to detect fluorescence in the visible range, e.g., using various types of counters. For example, Eu may be introduced into the Si-0 matrix forming Si-O-Eu bonds, (see, e.g., Levy et al. 1984, Fluorescence of europium(III) trapped in silica gel-glass as a probe for cation binding and for changes in cage symmetry during gel dehydration, Chemical Physics Letters 109(6): 593-597). Various variants of strontium aluminates may be used to enable marking with different colors (e.g., SrA14O7, Sr3A12O6, SrA112O19, Sr4A114O25 and combinations thereof, possibly with europium complexes as well). It is noted that the types and amounts of the fluorescent material(s) may be selected and included while not changing the safety and inertness of particles, e.g., using trace amounts, <0.1wt% and / or biosafe materials. It is further noted that the fluorescent material(s) may be present in either or both cores and / or shells in core-shell particles. In some embodiments, fluorescent material(s) may be present in hydrophobic surface material. Different types or amounts of fluorescent materials may be present in the particles, enabling different identifiers, or signatures, for different batches of particles powders. These identifiers are explained in greater detail below. These fluorescent materials may be selected so as to be UV resistant in the stratosphere as is known in the art. It is also possible to create markings that combine the various methods described, for example the presence of elements with fluorescence, or with isotopes, or any combination of these.

[0144] In further embodiments, the particles may include engineered color centers or point defects that provide unique and highly stable optical or spectroscopic signatures for postrelease identification. Engineered color centers, such as vacancy centers, impurity-vacancy complexes, or electronically active defects introduced by controlled doping, irradiation, or thermal treatment, produce characteristic absorption or fluorescence bands that can be distinguished from naturally occurring atmospheric particles. Similarly, engineered point defects, including substitutional dopants, interstitials, or oxygen vacancies, may be incorporated into the core or shell material to generate identifiable Raman, photoluminescence, or electron-paramagnetic-resonance responses. These defect-based markers remain embedded within the particle lattice, are resistant to degradation under stratospheric UV exposure, andP-635226-PCenable highly specific atribution and tracking of the dispersed particles during sampling or remote detection.

[0145] In various embodiments, the use of different internally marked particle batches may enable selective plume tracking and temporal differentiation of dispersal events. For example, powder from a first hopper may be dispersed during a first interval of flight, allowing the resulting plume to be monitored to determine particle transport pathways, spatial dispersion paterns, and chemical or physical transformations over time. Powder from a second hopper, containing a different internal marker, may then be dispersed during a subsequent interval. Because each batch is uniquely identifiable, the system may distinguish the behavior of different dispersal events within the same atmospheric region, enabling comparative analysis of particle residence time, transport direction, setling rate, or atmospheric reactivity. Such selective tracking capability may improve plume modeling accuracy, provide empirical validation of dispersion forecasts, and support characterization of atmospheric conditions or particle chemistry under controlled test scenarios. Differences in plume shape, density, or dispersion rate may be measured, imaged, or sampled to assess plume dynamics. Selective switching may be controlled manually or automatically, and may be coordinated with aircraft altitude, airspeed, temperature, humidity or wind conditions.

[0146] In certain embodiments, the aerial platform may further include systems configured for in-situ characterization systems for identifying particles and testing of particleair interactions. This in-situ testing may occur during flights of the aerial platform dedicated to particle capture and testing without releasing particle batches into the atmosphere. In further embodiments, a flight of the aerial platform may perform both in-situ particle capture / testing and batch dispersal. The characterization system may be configured to obtain real-time, in-situ testing data during flight without requiring release of particles outside the aerial platform.

[0147] In certain embodiments, one or more sampling tubes may be positioned along an exterior surface of the aerial platform and may be configured to continuously collect atmospheric air during flight. The sampling tubes may convey air at ambient temperature and pressure into a sealed reaction chamber located within the aerial platform. The reaction chamber may be insulated or temperature-controlled to maintain environmental fidelity. The sampling system may operate continuously or on-demand, and may incorporate flow regulation components to control sample volume, flow rate, or sampling interval.

[0148] In some embodiments, particles may be introduced into the sealed reaction chamber for controlled interaction with the sampled air. Particle introduction may be performed using an injection system configured to aerosolize powder and deliver the aerosolized particles into the chamber interior. Alternatively, particles may be provided as a fixed coating alongP-635226-PCinterior chamber surfaces or along the surfaces of interchangeable inserts placed within the chamber. The coating or inserts may be arranged such that collected atmospheric air flows over the coated surfaces, enabling particle-air interactions without dispersing particles into the external atmosphere.

[0149] The characterization system may comprise one or more instruments, including, for example, chemical ionization mass spectrometry (CIMS) systems, single-particle mass Spectrometry (SPMS) systems, tunable diode laser absorption spectroscopy systems, and additional particle size or composition analyzers. The characterization system may operate in real time, acquiring and correlating data about reaction kinetics, gas composition changes, or particle size modification during exposure to sampled air. In-situ testing results may enable direct evaluation of reaction rates, atmospheric transformation pathways, surface chemistry effects, and environmental sensitivities under flight conditions.

[0150] In some embodiments, the characterization system may further comprise a containment and collection system configured to retrieve particles or reaction products from the sealed chamber for post-flight laboratory analysis. The containment system may include removable filters, deposition plates, particle collectors, flow-through capture elements, or sample extraction ports.

[0151] In certain embodiments, the characterization system may comprise multiple interchangeable reaction chambers that can be swapped during or between flights to evaluate different particle samples under similar atmospheric conditions. Environmental monitoring components may be configured to measure and record atmospheric temperature, pressure, and humidity during test exposure, allowing correlation between particle response and environmental conditions.

[0152] Elements from Figures 1A-6 may be combined in any operable combination, and the illustration of certain elements in certain figures and not in others merely serves an explanatory purpose and is non-limiting. It is noted that disclosed values are understood to be possibly modified to encompass ±10% of the respective values.

[0153] Below (in paragraph form) are sample claims defining at least in part the technology described herein.

[0154] 1. An aerial dispersal system configured to disperse particles to the atmosphere from an aerial platform, the system comprising: a feeder configured to transport a powder comprising a plurality of particles; and a dispersal mechanism configured to receive and disperse the powder from the aerial platform, the dispersal mechanism further configured to receive at least one of compressed air and energy from the aerial platform, the at least one ofP-635226-PCcompressed air and energy deagglomerating the plurality of particles in the powder prior to being dispersed from the aerial platform to the atmosphere.

[0155] 2. The aerial dispersal system of claim 1, wherein the plurality of particles are deagglomerated as a result of exposure to at least one of high-shear turbulent flow and drag forces from accelerating flow within the dispersal mechanism.

[0156] 3. The aerial dispersal system of claim 2, further comprising at least one venturi duct and flow constriction configured to accelerate the flow.

[0157] 4. The aerial dispersal system of claim 1, further comprising an inlet in the aerial platform for receiving ram air generated by forward motion of the aerial platform, the ram air at least in part supplying the air or energy for deagglomeration.

[0158] 5. The aerial dispersal system of claim 1, further comprising at least one of an air compressor, an air-gas turbine and pressurized air containers onboard the platform for supplying the compressed air.

[0159] 6. The aerial dispersal system of claim 1, further comprising one or more powder storage vessels for storing the powder inside the aerial platform, the feeder configured to transfer the powder from the one or more powder storage vessels.

[0160] 7. The aerial dispersal system of claim 6, further comprising one or more conveyors for conveying the powder from the feeder to the dispersal mechanism.

[0161] 8. The aerial dispersal system of claim 7, wherein the one or more conveyors are configured to operate by negative pressure, positive pressure, or by a conveyor belt.

[0162] 9. The aerial dispersal system of claim 1, wherein the dispersal mechanism comprises a discharge orifice through which the deagglomerated particles are dispersed to the atmosphere.

[0163] 10. The aerial dispersal system of claim 1, wherein the feeder operates by at least one of gravity and negative pressure.

[0164] 11. The aerial dispersal system of claim 1, wherein the feeder comprises a feeding aid configured to fluidize the powder using at least one of a fluidizing element and a vibration element.

[0165] 12. The aerial dispersal system of claim 1, wherein the feeder operates to transfer the powder by negative pressure, and wherein the feeder comprises a dosing mechanism to control the negative pressure.

[0166] 13. The aerial dispersal system of claim 12, wherein the dosing mechanism comprises at least one of a rotary valve, a pinch valve, a butterfly valve, and a gate valve.P-635226-PC

[0167] 14. The aerial dispersal system of claim 13, further comprising a restraint for mitigating against spontaneous escape of the powder from the aerial platform.

[0168] 15. The aerial dispersal system of claim 1 , further comprising a purge mechanism for dislodging stuck powder from all portions of the dispersal system that house or transport the powder.

[0169] 16. The aerial dispersal system of claim 15, wherein the purge mechanism operates using compressed air to dislodge stuck powder.

[0170] 17. The aerial dispersal system of claim 1, wherein the feeder comprises a sensor and control mechanism configured to determine how much powder remains in the feeder and how much powder is being dispersed from the feeder over time.

[0171] 18. The aerial dispersal system of claim 17, wherein the sensor and control mechanism comprise at least one of a weighing scale and a powder surface level sensor.

[0172] 19. The aerial dispersal system of claim 1, further comprising an eductor using a pressure difference to mix the powder with the compressed air to deagglomerate particle aggregations in the powder.

[0173] 20. The aerial dispersal system of claim 1, further comprising at least two eductors with an intermediate container, which together are configured to deagglomerate particle aggregations in the powder.

[0174] 21. The aerial dispersal system of claim 1, further comprising at least one deagglomeration target configured to receive the powder, the target comprising at least one of a direct-impact surface and a mesh structure.

[0175] 22. The aerial dispersal system of claim 1, configured to store an amount of powder within a fuselage of the aerial platform and to disperse the amount of powder using at least one of compressed air and energy supplied from onboard systems of the aerial platform.

[0176] 23. The aerial dispersal system of claim 1, wherein the compressed air is generated onboard the platform, including one of air bled from turbine engines and ram air supplied through platform inlets.

[0177] 24. The aerial dispersal system of any one of claim 23, further comprising a turbine engine configured to provide compressed air at a required flow rate, temperature, and pressure for the dispersal mechanism.

[0178] 25. The aerial dispersal system of claim 1, configured to direct air from outside the aerial platform through the dispersal system with minimal drag and energy loss, including by minimizing pressure losses in an air inlet for receiving ram air and in one or more components that compress air.P-635226-PC

[0179] 26. The aerial dispersal system of claim 25, further configured to increase thrust generated by discharge of the air and dispersed particles from the aerial platform.

[0180] 27. The aerial dispersal system of claim 1, wherein a center of gravity of the aerial platform is maintained within allowable limits by at least one of controlling fuel mass distribution among fuel tanks and controlling powder mass distribution within the storage vessels.

[0181] 28. The aerial dispersal system of claim 1, wherein unused fuel-tank volume of the aerial platform is configured for use to store the powder.

[0182] 29. The aerial dispersal system of claim 1, wherein the fuselage of the aerial platform is modified to operate with a partially pressurized or unpressurized cabin that houses the dispersal system to reduce weight and / or energy requirements.

[0183] 30. The aerial dispersal system of claim 1, configured to disperse at least one ton of particles per flight of the aerial platform.

[0184] 31. The aerial dispersal system of claim 1, further comprising at least one sensor configured to monitor one or more of powder dispersal rate, particle size distribution, and particle electric charge distribution.

[0185] 32. The aerial dispersal system of claim 1, wherein the particles comprise one or more of particles of at least one of: amorphous silica particles, calcium carbonate particles, core-shell particles comprising one or more of silica, calcium carbonate -including its amorphous form (ACC) and its crystalline polymorphs calcite, vaterite, aragonite - hydroxyapatite, magnesium calcite, zirconia oxide, gypsum, magnesium carbonate, unspecific magnesite, dolomite, mixtures of calcium carbonate and magnesium carbonate, calcium alginate, maltodextrin and calcium sulfate dihydrate, where the particles may have a hydrophobic and / or unreactive coating.

[0186] 33. The aerial dispersal system of claim 1, wherein the particles comprise an outer surface configured for minimizing interparticle cohesive forces.

[0187] 34. The aerial dispersal system of claim 1, wherein the particles comprise an outer surface configured to minimize energy requirements for deagglomeration.

[0188] 35. The aerial dispersal system of claim 1, configured to disperse the particles at a rate of at least 1 tons per hour using compressed air at a throughput of at least 1 standard cubic meter per second.

[0189] 36. The aerial dispersal system of claim 1, wherein the feeder and dispersal mechanism are configured within Unit Load Device (ULD) containers standardized for aircraft loading, transport, and unloading.P-635226-PC

[0190] 37. The aerial dispersal system of claim 1, wherein the compressed air is modulated or pulsed to achieve agglomeration while reducing the amount of compressed air required for dispersal of the particles.

[0191] 38. The aerial dispersal system of claim 1, wherein the deagglomeration mechanism is configured to optimize deagglomeration of agglomerates of submicron particles by inducing at least one of: fine-scale turbulent eddies, high turbulent dissipation rates, rapid flow acceleration / deceleration, particle trajectories maximizing the residence time in regions of high turbulent shear and / or particle trajectories maximizing collisions between particles and surfaces and / or other particles.

[0192] 39. The aerial dispersal system of claim 38, wherein the particle trajectories are tailored by manipulating the local air velocity in relation to the Stokes number of particle aggregates using at least one of: geometrical protrusions or corrugations enhancing turbulence and mixing, turns and / or bends and / or flow combining elements.

[0193] 40. The aerial dispersal system of claim 1, wherein the deagglomeration mechanism is configured to break down agglomerates by applying pressure gradients and / or rapid acceleration by passing the flow through shock waves.

[0194] 41. The aerial dispersal system of claim 1 , wherein the powder is first aerated before conveying.

[0195] 42. The aerial dispersal system of claim 1, wherein powder conveying and / or deagglomeration are aided by the addition of at least one of anti -caking agents and flow -enhancing additives.

[0196] 43. The aerial dispersal system of claim 1, wherein larger agglomerates of the powder are initially broken down by a milling mechanism.

[0197] 44. The aerial dispersal system of claim 1, further comprising multiple hoppers containing particles with different internal markings and a switching mechanism configured to enable selective dispersal from each hopper, wherein the different internal markings enable at least one of tracking, monitoring and governance of the plurality of particles after dispersion of the plurality of particles in the atmosphere, and wherein the markers are present in amounts sufficient for detection by analytical techniques.

[0198] 45. An aerial dispersal system configured to disperse particles to the atmosphere from an aerial platform, the system comprising: a feeder configured to transport a powder comprising a plurality of particles; and a dispersal mechanism configured to receive and disperse the powder from the aerial platform, the dispersal mechanism generating an electric charge on the plurality of particles to electrostatically repel the particles from one another to prevent agglomeration.P-635226-PC

[0199] 46. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated by triboelectric charging resulting from frictional engagement between the particles and interior wall surfaces of the dispersal mechanism.

[0200] 47. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated and / or mediated by triboelectric charging resulting from frictional engagement between the particles.

[0201] 48. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated by corona discharge.

[0202] 49. The aerial dispersal system of claim 48, further comprising at least one corona discharge electrode configured to generate ions that impart electric charge to the particles.

[0203] 50. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated by dedicated triboelectric charging.

[0204] 51. The aerial dispersal system of claim 50, further comprising at least one of a triboelectric charging region having an interior surface configured to increase frictional interaction with the particles.

[0205] 52 The aerial dispersal system of claim 51, wherein the interior surface is configured to increase frictional interaction with the particles by providing material of the surface interior with a substantially different electron affinity than the particles and / or particle surfaces.

[0206] 53. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated by electrostatic induction.

[0207] 54. The aerial dispersal system of claim 53, further comprising at least one pair of induction electrodes configured to establish an electric field that induces charge on the particles.

[0208] 55. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated by mixing the particles with ionized air.

[0209] 56. The aerial dispersal system of claim 55, further comprising at least one ionizing element configured to ionize compressed air upstream of the dispersal mechanism.

[0210] 57. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated and / or mediated between particles by exposure to high -shear turbulent flow within the dispersal mechanism.P-635226-PC

[0211] 58. The aerial dispersal system of claim 45, further comprising at least one charging component located downstream of the discharge orifice that is configured to add electric charge on the plurality of particles after their release.

[0212] 59. An airborne chemical characterization system for measuring the interaction between particles and the atmospheric air, without releasing particles into the environment, the system comprising: an aerial platform configured for sustained flight at altitudes of interest; a real-time air sampling system within the aerial platform comprising at least one sampling tube configured to continuously collect atmospheric air at ambient temperature and pressure conditions; a sealed reaction chamber positioned within the aerial platform; a controlled particle introduction assembly comprising at least one of: (i) an injection system configured to introduce aerosolized particles into the sealed reaction chamber for interaction with the collected air; or (ii) a coating of particles deposited on an internal surface of the reaction chamber or on a surface of interchangeable inserts positioned within the reaction chamber; and a real-time in-situ analytical detection system configured to monitor chemical interactions, reaction kinetics, and / or particle behavior without any release of materials to the external environment.

[0213] 60. The airborne chemical characterization system of claim 59, wherein the real-time analytical detection system comprises at least one of: a Chemical Ionization Mass Spectrometry (CIMS) system configured for sensitive in-flight quantification of atmospheric components and / or reaction products, a Single-Particle Mass Spectrometry (SPMS) system configured for sensitive in-flight characterization and quantification of ambient and / or introduced particles, tunable diode laser absorption spectroscopy systems configured for species-specific detection of trace gases, and additional particle size and composition analyzers configured to monitor changes in test particle characteristics during controlled exposure to sampled air.

[0214] 61. The airborne chemical characterization system of any one of claims 59, further comprising at least one of: a containment and collection system configured to capture test particles and / or reaction products for post-flight analysis, multiple interchangeable reaction chambers enabling testing of different particle samples during a single flight mission, and environmental parameter monitoring systems configured to record at least one parameter of temperature, pressure, and humidity during particle interaction studies.

[0215] 62. A method of dispersing particles from an airplane, the method comprising controllably dispersing the particles from the airplane out into the stratosphere using energy and compressed air provided from the airplane, wherein the particles are fed for dispersalP-635226-PCas a powder and wherein the particles are configured to have diameters between 0.05pm and 10pm and to not agglomerate.

[0216] 63. The method of claim 62, further comprising: conveying the powder to be fed for dispersal, feeding the powder by gravity or by negative pressure while dosing, sensing and controlling the feed, and deagglomerating the powder.

[0217] 64. The method of claim 63, wherein the feeding of the powder is caried out by gravity and further comprising fluidizing the powder prior to the feeding.

[0218] 65. The method of claim 64, wherein the deagglomerating of the powder is carried out by one or more of negative pressure and by impinging the powder onto a target.

[0219] 66. The method of claim 63, wherein the conveying of the powder is carried out by negative pressure.

[0220] 67. The method of claim 62, further comprising monitoring the particles immediately after their dispersal.

[0221] The present application discloses dispersal of particles. One example of these particles having properties facilitating proper deagglomeration and dispersal is disclosed in PCT Patent Application No. PCT / IL2025 / 050999, filed on November 10, 2025. Such particles and methods therefore are defined in the following claims (presented here in paragraph form):

[0222] 1. A plurality of particles, each particle of the plurality of particles comprising: at least one of amorphous silica and calcium carbonate; and a particle diameter in the range of 0.1 pm to 2.0 pm; the plurality of particles configured for dispersal in the stratosphere for solar radiation modification; the plurality of particles further configured to be safe for inhalation and configured to be safe for the environment; the plurality of particles further configured to be inert to a number of reactive compounds found in the stratosphere; and the plurality of particles configured to reside in at least one of the stratosphere and troposphere for a predetermined period of time.

[0223] 2. The plurality of particles of claim 1, wherein the plurality of particles are substantially spherical.

[0224] 3. The plurality of particles of claim 1 , wherein each particle of the plurality of particles comprises a core of material that scatters ultraviolet (UV) light, visible light and near infrared (NIR) light and is substantially non-absorbing in the infrared spectrum, particularly in the terrestrial infrared window.

[0225] 4. The plurality of particles of claim 1 , wherein each particle of the plurality of particles comprises a core of substantially non-absorbing dielectric material.P-635226-PC

[0226] 5. The plurality of particles of claim 4, wherein the core is formed of calcium carbonate, the calcium carbonate core formed by a reaction between one of calcium nitrate and calcium chloride with sodium carbonate, when both are dissolved in an aqueous solution containing a surfactant.

[0227] 6. The plurality of particles of claim 5, wherein the surfactant is one of Tween 20 and STPP.

[0228] 7. The plurality of particles of claim 4, wherein the core material is formed of one of silica, calcium carbonate - including its amorphous form (ACC) and its crystalline polymorphs calcite, vaterite, aragonite, - hydroxyapatite, magnesium calcite, zirconia oxide, gypsum, magnesium carbonate, inspecific magnesite, dolomite, mixtures of calcium carbonate and magnesium carbonate, calcium alginate, maltodextrin and calcium sulfate dihydrate.

[0229] 8. The plurality of particles of claim 4, wherein each particle of the plurality of particles further comprises a shell layer comprising amorphous silica around the core.

[0230] 9. The plurality of particles of claim 8, wherein each particle of the plurality of particles further comprises a coating around the shell comprising a hydrophobic material.

[0231] 10. The plurality of particles of claim 9, wherein hydrophobic material a) reduces nucleation in the troposphere, in the polar stratosphere, and near the exhaust of a dispersing aircraft, and b) reduces coagulation with background sulfate aerosols.

[0232] 11. The plurality of particles of claim 8, wherein each particle of the plurality of particles further comprises a coating around the shell comprising anon-polar material.

[0233] 12. The plurality of particles of claim 1 , wherein each particle of the plurality of particles each comprises a core having a substantially spherical geometry.

[0234] 13. The plurality of particles of claim 1 , wherein each particle of the plurality of particles each comprises a core having a non-substantially spherical geometry.

[0235] 14. The plurality of particles of claim 1, wherein the plurality of particles are manufactured by a Stober sol-gel manufacturing process.

[0236] 15. The plurality of particles of claim 1, wherein the plurality of particles are manufactured by non-Stober sol-gel processes comprising one or more of vaporized metal combustion, liquid-phase synthesis and flame fusion.

[0237] 16. The plurality of particles of claim 1, wherein the plurality of particles have an outer surface functionalized with short-chain silane molecules.

[0238] 17. The plurality of particles of claim 16, wherein the short-chain silane molecules are free of carbon-carbon bonds.

[0239] 18. The plurality of particles of claim 16, wherein the short-chain silane molecules are primarily carbon-silicon bonds.P-635226-PC

[0240] 19. The plurality of particles of claim 16, wherein the short-chain silane molecules comprise one or more of tetra-ethoxy-silane, tetra-methoxy-silane, tri methyl methoxy silane, dimethyl dimethoxy silane, monomethyl trimethoxy silane, tri methyl ethoxy silane, dimethyl diethoxy silane, monomethyl triethoxy silane, trimethylsilane (TMS), methyltrimethoxysilane (MTMS) and / or combinations thereof.

[0241] 20. The plurality of particles of claim 1, wherein the plurality of particles are configured with functional surface groups for steric hindrance to reduce adsorption of stratospheric components in the stratosphere.

[0242] 21. The plurality of particles of claim 1 , wherein each particle of the plurality of particles further comprises a shell, and a coating around the shell comprising a non-polar material.

[0243] 22. The plurality of particles of claim 1 , wherein each particle of the plurality of particles further comprises coating around the shell comprising a hydrophobic material.

[0244] 23. The plurality of particles of claim 22, wherein hydrophobic material a) reduces nucleation in the troposphere, in the polar stratosphere, and near the exhaust of a dispersing aircraft, and b) reduces coagulation with background sulfate aerosols.

[0245] 24. The plurality of particles of claim 22, wherein the silica coating is prepared in a mixture of ethanol and water together with ammonium hydroxide.

[0246] 25. The plurality of particles of claim 24, the silica coating further comprising a hydrophobic coating applied using methyltrimethoxysilane (MTMS) in a water -ethanol mixture.

[0247] 26. The plurality of particles of claim 1, wherein the plurality of particles undergo a calcination process to reduce surface hydroxyl groups.

[0248] 27. The plurality of particles of claim 1, wherein the plurality of particles are configured to scatter light in at least one of the visible, ultraviolet (UV) and infrared (IR) ranges, without significant absorption in these ranges.

[0249] 28. The plurality of particles of claim 1, wherein the plurality of particles are configured to scatter incoming solar radiation while not absorbing solar or terrestrially emitted infrared (IR) radiation.

[0250] 29. The plurality of particles of claim 1, wherein the plurality of particles are configured to reside in the stratosphere for a predetermined period of time of three months to three years.

[0251] 30. The plurality of particles of claim 1, wherein the plurality of particles have an outer surface configured for minimizing interparticle cohesive forces.P-635226-PC

[0252] 31. The plurality of particles of claim 1, wherein the plurality of particles have an outer surface configured for minimizing energy requirements for deagglomeration.

[0253] 32. The plurality of particles of claim 1, wherein the solar radiation modification is accomplished through stratospheric aerosol injection.

[0254] 33. The plurality of particles of claim 1, wherein the plurality of particles have a shell surrounding a core, the shell having a smooth surface area with a Brunauer-Emmett-Teller (BET) specific surface area of less than 50 m2 / g.

[0255] 34. The plurality of particles of claim 1, wherein the plurality of particles have a shell surrounding a core, the shell having a smooth surface area with a Brunauer- Emmett-Teller (BET) specific surface area of less than 10 m2 / g.

[0256] 35. The plurality of particles of claim 1, wherein the plurality of particles form a powder, wherein air injected through the powder causes the powder to behave as a fluid.

[0257] 36. The plurality of particles of claim 1, wherein the particles dissolve into compounds that overtime become constituents of living organisms.

[0258] 37. The plurality of particles of claim 1, wherein the core is formed of a silicate solutions.

[0259] 38. The plurality of particles of claim 32, wherein the silicate source is sodium silicate.

[0260] 39. The plurality of particles of claim 38, wherein the sodium silicate core formed by a solution of sodium silicate in water, mixed with PEG 3000, acetic acid, and water under heating between 40°C and 80°C, with the addition of surfactants.

[0261] 40. The plurality of particles of claim 39, wherein the surfactants comprise one of CMC, PAA, and STPP.

[0262] 41. The plurality of particles of claim 1, wherein the plurality of particles are formed by the steps of: adding polyethylene glycol to a first aqueous solution; combining an acid and the first aqueous solution; adding sodium silicate to a second aqueous solution; combining the first aqueous solution comprising the polyethylene glycol with the second aqueous solution comprising the sodium silicate, wherein the acid reduces a high pH of the sodium silicate causing silicate ions to hydrolyze and condense into a silica gel network, and wherein the polyethylene glycol causes formation of substantially spherical particles.

[0263] 42. The plurality of particles of claim 41 , wherein the step of combining acid to the first aqueous solution comprises the step of adding the first aqueous solution to acetic acid.

[0264] 43. The plurality of particles of claim 1, wherein the plurality of particles comprise materials having absorption peaks in the IR spectrum, the materials comprising atP-635226-PCleast one of silica having an absorption peak in IR at about 7 to 13pm and calcium carbonate having an absorption peak in IR at about 7 to 13 pm, the absorption peaks allowing monitoring the dispersal of particles by measurements of IR radiation around the absorption peaks, wherein the plurality of particles comprise at least one of silica having an absorption peak in IR at about 7 to 13 pm and calcium carbonate having an absorption peak in IR at about 7 to 13pm. the at least one absorption peak allowing monitoring the dispersal of particles by measurements of IR radiation around the at least one absorption peak.

[0265] 44. The plurality of particles of claim 1, wherein at least a portion of the plurality of particles are configured to absorb at least one of shortwave and longwave radiation to provide localized positive radiative forcing for mitigating excessive negative radiative forcing.

[0266] 45. The plurality of particles of claim 44, wherein the at least portion of the plurality of particles comprise one of Fe2O3 and Fe3O4.

[0267] 46. The plurality of particles of claim 1, wherein a negligible amount of <100nm particles are fabricated.

[0268] 47. A plurality of particles, each particle of the plurality of particles comprising:

[0269] a solid aerosol configured for dispersal in the stratosphere for solar radiation modification; and markers enabling at least one of tracking, monitoring and governance of the plurality of particles after dispersion of the plurality of particles in the atmosphere, wherein the markers are present in amounts sufficient for detection by analytical techniques without altering an inertness, safety, or optical properties of the particles.

[0270] 48. The plurality of particles of claim 47, wherein the plurality of particles are comprised of one of silica and calcium carbonate.

[0271] 49. The plurality of particles of claim 47, wherein the plurality of particles are configured to be inert to at least most compounds found in stratosphere

[0272] 50. The plurality of particles of claim 47, wherein the particles of the plurality of particles each range between 0.1pm and 2.0pm.

[0273] 51. The plurality of particles of claim 50, wherein a negligible amount of <100nm particles are fabricated.

[0274] 52. The plurality of particles of claim 50, wherein a size of the particles and a uniform substantially spherical geometry of the particles enables tracking of the particles independently of the markers.

[0275] 53. The plurality of particles of claim 47, wherein the markers are provided on an outer surface of the particle.P-635226-PC

[0276] 54. The plurality of particles of claim 47, wherein the markers are provided around at least one of the core, the shell and the coating of the particle.

[0277] 55. The plurality of particles of claim 47, wherein the markers enable tracking by allowing positions of the particles to be tracked as they move within the atmosphere .

[0278] 56. The plurality of particles of claim 47, wherein the markers enable monitoring by allowing analysis of the particles after being recaptured from residence in the atmosphere.

[0279] 57. The plurality of particles of claim 47, wherein the markers enable governance by allowing identification of a source of particles dispersed in the atmosphere.

[0280] 58. The plurality of particles of claim 47, wherein the markers are provided at trace amounts ranging between a few parts-per-million (ppm) and a few hundreds of ppm in mass.

[0281] 59. The plurality of particles of claim 47, wherein the markers comprise trace metals.

[0282] 60. The plurality of particles of claim 59, wherein the trace metals are taken from the group consisting of Ca, Zn, Sr, Fe, Cu, Al, K, Mg, Ti, Zr, Bi, Sn, Mo, Mn.

[0283] 61. The plurality of particles of claim 47, wherein the markers comprise stable isotopes.

[0284] 62. The plurality of particles of claim 61, wherein the stable isotopes are taken from the group consisting of29Si,13C,2H,18O,42Ca,43Ca,44Ca and46Ca.

[0285] 63. The plurality of particles of claim 47, wherein the markers comprise one or more of fluorescent materials, engineered color centers and point defects.

[0286] 64. The plurality of particles of claim 63, wherein the particles comprise fluorescent materials, and the fluorescent materials comprise luminescent transition metal cations.

[0287] 65. The plurality of particles of claim 47, wherein the plurality of particles are configured to be analyzed by at least one of Secondary Ion Mass Spectrometry (SIMS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) compositional analysis.

[0288] 66. The plurality of particles of claim 47, wherein the particles are designed to enable their identification by analytical techniques comprising airborne, in-situ particle mass-spectrometers, with ionization stages employing laser-ablation or plasma, followed by time-of-flight mass spectrometry.

[0289] 67. The plurality of particles of claim 47, further comprising nanometric spacer particles, having diameters ranging between lOnm and 50nm, which spacer particles are dry mixed with the plurality of particles to prevent agglomeration of the plurality of particles.P-635226-PC

[0290] 68. The plurality of particles of claim 67, further comprising one or more of a flow agent and an anti -caking agent to prevent clumping of plurality of particles.

[0291] 69. A method of monitoring the plurality of particles recited in claim 40, the method comprising the steps of: collecting a sample of atmosphere using an airborne vehicle; imaging the collected sample using a scanning electron microscope to identify candidate particles; targeting a candidate particle at a position identified by the scanning electron microscope with an ionizing beam; analyzing ions ejected from the candidate particle using time of flight secondary ion mass spectrometry to confirm that the spectrum matches the fabricated particle; and identifying the trace materials which were added and their quantities.

[0292] 70. The method of claim 69, further comprising the step of forming the particle by a Stober sol-gel manufacturing process.

[0293] 71. The method of claim 69, further comprising the step of forming the particle by non-Stober sol-gel processes comprising one or more of vaporized metal combustion, liquid-phase synthesis and flame fusion.

[0294] 72. The method of claim 69, wherein the step of targeting a candidate particle with an ion beam comprises the step of targeting the candidate particle at multiple positions around the candidate particle.

[0295] 73. A method for monitoring the plurality of particles recited in claim 40, comprising the steps of: collecting a sample of atmosphere into an airborne vehicle; ionizing individual particles using one of a plasma and laser-ablation; analyzing the ions using mass spectrometry to confirm that the spectrum matches the dispersed particle; and identifying the trace materials which were added and their quantities.

[0296] 74. The method of claim 73, wherein said step of forming the particle comprises the step of forming the particle by a Stober sol-gel manufacturing process.

[0297] 75. A plurality of particles, each particle of the plurality of particles comprising: a core comprising calcium carbonate; a substantially spherical shell formed around the core, the substantially spherical shell comprising amorphous silica; wherein the plurality of particles are configured for dispersal in the stratosphere for solar radiation modification; the plurality of particles further configured to be safe for inhalation and configured to be safe for the environment; and the plurality of particles further configured to be inert to at least most compounds found in the stratosphere.

[0298] 76. The plurality of particles of claim 75, further comprising a hydrophobic coating formed over the shell.P-635226-PC

[0299] 77. The plurality of particles of claim 75, wherein the amorphous silica and calcium carbonate dissolve over time into compounds that become constituents of living organisms.

[0300] 78. The plurality of particles of claim 75, wherein the core comprises substantially spherical calcium carbonate.

[0301] 79. The plurality of particles of claim 75, wherein the core comprises non-substantially spherical calcium carbonate.

[0302] 80. A method of forming an environmentally safe, inert and light scattering particle for use in solar radiation modification, comprising the steps of: adding a silane shell material to a solvent mixture; adding calcium carbonate cores to the solvent mixture; vibrating the solvent mixture including the silane shell material and calcium carbonate cores; and adding a base catalyst for the hydrolyzation of the silane shell material and enabling the hydrolyzed silane shell material to condense into solid silane shells around individual calcium carbonate cores.

[0303] 81. The method of claim 80, wherein the step of adding a silane shell material to the solvent mixture comprises the step of adding methoxymethyl silane to the solvent mixture.

[0304] 82. The method of claim 80, wherein the step of adding a base catalyst to the solvent mixture comprises the step of adding ammonium hydroxide to the solvent mixture.

[0305] 83. The method of claim 80, further comprising the step of forming a nonpolar coating around the silane shells.

[0306] 84. The method of claim 80, further comprising the step of forming a hydrophobic coating around the silane shells.

[0307] 85. The plurality of particles of claim 84, wherein the plurality of particles are configured with functional surface groups for steric hindrance to reduce adsorption of stratospheric components in the stratosphere.

[0308] 86. The method of claim 84, wherein the hydrophobic coating a) reduces nucleation in the troposphere, in the polar stratosphere, and near the exhaust of a dispersing aircraft, and b) reduces coagulation with background sulfate aerosols.

[0309] 87. The method of claim 84, wherein said step of forming a hydrophobic coating around the silane shells comprises the steps of: deagglomerating the particles of calcium carbonate cores with silane shells; adding the deagglomerated particles to solvent solution; vibrating the solvent solution including the deagglomerated particles; and adding an alkoxysilane to the solvent solution, the alkoxysilane condensing over time into Si-O-Si networks that bond to the existing silane shell to provide a hydrophobic outer surface.P-635226-PC

[0310] 88. The method of claim 87, wherein the step of adding an alkoxysilane to the solvent solution comprises the step of adding methoxymethyl silane to the solvent solution.

[0311] 89. The method of claim 87, wherein the process further comprises adding tetra alkoxy silanes.

[0312] 90. The method of claim 89, wherein the tetra alkoxy silanes comprise TEOS.

[0313] 91. The method of claim 90, wherein the TEOS provides a hydrophilic coating.

[0314] 92. The method of claim 91, further comprising hydrophobic coating over the hydrophilic coating.

[0315] 93. A method of forming an environmentally safe, inert and light scattering particle for use in solar radiation modification comprising a calcium carbonate core, the method comprising the steps of: dissolving a sodium carbonate precursor in a first aqueous solution; adding a surface -active moiety to the first aqueous solution; dissolving a calcium precursor such as calcium chloride or calcium nitrate in a second aqueous solution; mixing the first aqueous solution comprising the carbonate precursor with the second aqueous solution comprising the calcium precursor, mixing of the first and second aqueous solutions forming the calcium carbonate cores, the surface-active moiety adsorbing to the surface of the calcium carbonate cores to block or slow the growth of the calcium carbonate cores in certain directions, preventing uncontrolled crystallization; and separating the calcium carbonate cores from the mixed first and second aqueous solutions.

[0316] 94. The method of claim 93, wherein the concentration of the carbonate precursor in the first aqueous solution is equal to the concentration of the calcium precursor in the second aqueous solution.

[0317] 95. The method of claim 93, further comprising the step of deagglomerating the calcium carbonate cores.

[0318] 96. The method of claim 95, further comprising the step of drying the calcium carbonate cores at a first temperature to form substantially spherical particles.

[0319] 97. The method of claim 96, wherein the first temperature is 40°C - 70°C.

[0320] 98. The method of claim 95, further comprising the step of drying the calcium carbonate cores at a second temperature to form cubic particles.

[0321] 99. The method of claim 98, wherein the second temperature is 60°C to 150°C.P-635226-PC

[0322] 100. The method of claim 93, wherein the step of dissolving a carbonate precursor into the first aqueous solution comprises the step of dissolving sodium carbonate into the first aqueous solution.

[0323] 101. The method of claim 93, wherein the step of dissolving a calcium precursor in the second aqueous solution comprises the step of dissolving calcium chloride into the second aqueous solution.

[0324] 102. The method of claim 93, wherein a silica shell layer is attached to the calcium carbonate core after formation of the calcium carbonate core, and wherein the attachment is affected such that the silica layers penetrate into the structure of the calcium carbonate core to form a network of mechanical interlocking.

[0325] The present application discloses dispersal of particles. One example of methods of monitoring and adjusting dispersal based on feedback is disclosed in PCT Patent Application No. PCT / IL2025 / 051069, filed on December 1, 2025. Such particles and methods therefore are defined in the following claims (presented here in paragraph form):

[0326] 1. A method of historical tracking and authentication of deployed aerosol particles for solar radiation modification, the method comprising: (a) creating a data record for a batch of particles at a time of fabrication, the data record including at least one of: (i) a batchspecific particle identifier derived from a known marker incorporated into each particle in the batch; (ii) a location of manufacture; (iii) a date of manufacture; (iv) a composition of the particles in the batch, including the marker incorporated therein; (v) an identity of a manufacturer; (vi) one or more specifications setting out the expected behavior of the particle once in the atmosphere; and (vii) a batch designation; (b) storing the data record in a memory in association with the batch-specific particle identifier; (c) following deployment of the batch of particles into the atmosphere, capturing one or more particles from the atmosphere or from an Earth surface location; (d) analyzing the one or more captured particles to identify any marker incorporated therein; (e) authenticating a captured particle as belonging to the batch by matching any identified marker to the stored batch-specific particle identifier; and (f) retrieving the data record associated with the batch-specific particle identifier and using the retrieved data to determine at least one of: (i) a time elapsed since deployment of the batch; (ii) whether the captured particle remained chemically and structurally stable; (iii) whether the captured particle exhibited degradation, transformation, or reaction in the environment; and (iv) whether the captured particle performed in accordance with the one or more specifications contained in the data record.P-635226-PC

[0327] 2. The method of claim 1, further comprising the step, at one or more times in a lifecycle of the particle batch after the steps (a) and (b), of: identifying the marker signature of the particles in the batch, and updating the stored data record for the particle by storing additional data in association with the particle identifier.

[0328] 3. The method of claim 2, wherein the step of updating the stored data record after the steps (a) and (b), comprises the step of updating the stored data record with at least one of: (i) a type of aerial transport used to transport the particle batch to a point of deployment, (ii) a storage configuration of the particle during transport to the point of deployment, (iii) an elevation of the point of deployment, (iv) a geographic-coordinates based location of the point of deployment, (v) a date and time of deployment, and (vi) identities of other particles or batches co-deployed.

[0329] 4. The method of claim 1, wherein the batch-specific particle identifier is generated by mapping concentration levels of N different marker substances incorporated into the particles to N corresponding positional digits or characters of the identifier, such that each marker substance is assigned to a predefined position in the identifier based on a predetermined encoding convention.

[0330] 5. The method of claim 4, wherein the marker incorporated into each particle comprises one or more of an elemental marker, an isotopic marker, an engineered defect, or a trace-material inclusion present at parts-per-million levels.

[0331] 6. The method of claim 4, wherein the marker substance incorporated into one or more of the particles in the batch of particles comprises one or more materials having one or more defined absorption peaks in an infrared (IR) spectrum.

[0332] 7. The method of claim 4, further comprising the step of encrypting the particle identifier prior to storage.

[0333] 8. The method of claim 7, further comprising the step of periodically changing the encryption key of the particle identifier and updating stored encrypted particle identifier in storage.

[0334] 9. The method of claim 1, wherein the step of analyzing the one or more captured particles comprises analyzing marked particles using mass spectrometry techniques employing laser-ablation or plasma ionization sources.

[0335] 10. The method of claim 1, wherein the step of analyzing the one or more captured particles comprises analyzing marked particles using one or more of Time-of-Flight Secondary Ion Mass Spectrometry, Inductively Coupled Plasma Mass Spectrometry, Scanning Electron Microscopy, and Energy Dispersive X-ray Spectroscopy.P-635226-PC

[0336] 11. The method of claim 1, wherein said step (a) of creating a data record comprises the step (vi) of storing one or more specifications setting out the expected behavior of the particle once in the atmosphere, wherein the expected behavior of the particle comprises one or more of: predicted residence time, predicted optical reflectance, predicted chemical stability, and predicted inertness to atmospheric compounds.

[0337] 12. The method of claim 1, further comprising authenticating the batch of particles prior to takeoff of an aerial transport carrying the batch of particles by identifying the marker incorporated in one or more particles of the batch and verifying that the identified marker corresponds to the batch-specific particle identifier stored in the data record.

[0338] 13. The method of claim 1, further comprising authenticating the batch of particles prior to deployment by identifying the marker incorporated in one or more particles of the batch and verifying that the identified marker corresponds to the batch-specific particle identifier stored in the data record.

[0339] 14. The method of claim 1, wherein the batch of particles comprises one or more materials having one or more absorption peaks in an infrared (IR) spectrum, and wherein the one or more absorption peaks enable monitoring of dispersal of the batch of particles by measuring IR radiation at or around the one or more absorption peaks.

[0340] 15. The method of claim 14, wherein the batch of particles comprises at least one of silica having an absorption peak in the IR spectrum at about 7 pm to 13 pm and calcium carbonate having an absorption peak in the IR spectrum at about 7 pm to 13 pm.

[0341] 16. A computer implemented method for controlling deployment of an aerosol layer of reflective particles for solar radiation modification, the method comprising: (a) defining a set of deployment parameters for the deployment of an aerosol layer of reflective particles, the set of deployment parameters directed to achieving a set of target objectives for the aerosol layer; (b) receiving measured data indicative of one or more of stratospheric, tropospheric, and earth surface conditions; (c) receiving measured data indicative of one or more characteristics of the deployed reflective aerosol layer; (d) determining current state characteristics of the aerosol layer based on the received measured data in steps (b) and (c); (e) comparing the current state characteristics of the aerosol layer to the target objectives of the aerosol layer to determine a deviation between the current state characteristics and the target objectives for the aerosol layer; and (f) adjusting the set of deployment parameters based on the deviation between the current state characteristics and the target objectives for the aerosol layer.

[0342] 17. The computer implemented method of claim 16, further comprising the step of controlling the operation of one or more sensors configured to gather and send the data received in steps (b) and (c).P-635226-PC

[0343] 18. The computer implemented method of claim 16, where the step (f) of adjusting the set of deployment parameters ramps up overtime such that the adjustment is small at a first time, and the adjustment is larger at a second time after the first time, the adjustment at the second time further being adjusted based on continued performance of steps (b), (c) and (d).

[0344] 19. The computer implemented method of claim 16, wherein the step (a) of defining a set of deployment parameters for the deployment of an aerosol layer of reflective particles correspond to defined climatic conditions which are used as a specified baseline climatology.

[0345] 20. The computer implemented method of claim 19 wherein the specified baseline comprises target range values of climatic parameters including, but not limited to, one or more of atmospheric temperature, earth surface temperature and precipitation spatial patterns.

[0346] 21. The computer implemented method of claim 19, wherein the baseline climatology is characterized by a desired, layer induced, radiative forcing, which can be characterized by a change in the top-of-atmosphere shortwave and longwave radiative fields.

[0347] 22. The computer implemented method of claim 21, wherein the top-of-atmosphere shortwave and longwave radiative fields measurements are acquired using measuring devices, including Earth observation satellites equipped with radiative flux measurement capabilities.

[0348] 23. The computer implemented method of claim 16, further comprising the step of controlling the operation of one or more actuators that set one or more of aerosol layer altitude, aerosol layer density, aerosol layer size distribution and aerosol layer geographic location.

[0349] 24. The computer implemented method of claim 23, wherein the operation of the one or more actuators is controlled with respect to deployment timing, longitude, latitude, and altitude, independently of each other.

[0350] 25. The computer implemented method of claim 23, wherein the operation of the one or more actuators is controlled to deploy particles in the aerosol of varying composition and sizes to enable different control characteristics and degrees of freedom in management of the aerosol layer.

[0351] 26. The computer implemented method of claim 25, where in particles in the aerosol layer comprise materials configured to absorb at least one of shortwave and longwave radiation, providing additional degrees of freedom for radiative control.P-635226-PC

[0352] 27. The computer implemented method of claim 16, wherein the step (c) of receiving measured data comprises receiving data indicative of stratospheric particle number density of the deployed reflective aerosol layer.

[0353] 28. The computer implemented method of claim 27, further comprising estimating indirectly the radiative forcing by tracking the evolution of particle optical properties from initial deployment through their stratospheric residence using predictive models calibrated with experimental data.

[0354] 29. The computer implemented method of claim 16, wherein said steps (b) of receiving measured data indicative of one or more of stratospheric, tropospheric, and earth surface conditions and (c) of receiving measured data indicative of one or more characteristics of the deployed reflective aerosol layer comprise the step of receiving the measured data from one or more sensor arrays.

[0355] 30. The computer implemented method of claim 29, wherein one or more of the one or more sensor arrays comprise optical particle measurement devices configured to measure particle number density of the deployed aerosol layer and to distinguish deployed particles from background stratospheric aerosols by differential sampling based on particle shape, size, composition, and / or refractory properties, thereby enabling testing, calibration, and operation of the control loop during ramp-up and deployment.

[0356] 31. The computer implemented method of claim 29, wherein one or more of the one or more sensor arrays comprise particle sampling devices comprising filters and / or impactors configured to estimate particle number density of the deployed aerosol layer and to collect particles for subsequent laboratory analysis, the devices further configured to distinguish deployed particles from background aerosols by differential sampling based on particle shape, size, composition, and / or refractory properties.

[0357] 32. The computer implemented method of claim 31, wherein the particle sampling devices are further configured to estimate electrical charge levels of the collected particles.

[0358] 33. The computer implemented method of claim 29, wherein one or more of the one or more sensor arrays comprise systems configured to estimate stratospheric temperature profiles using satellite-based microwave sounding, infrared sounding, temperature sensors carried by balloons and / or drones, and / or GPS radio occultation techniques.

[0359] 34. The computer implemented method of claim 16, wherein said step (d) of determining current state characteristics of the aerosol lay feedback for controlling the aerosol layer comprises the step of measuring particle number density and estimating the particleP-635226-PCscatering phase function using optical spectrometry at at least one angle and wavelength to estimate radiative forcing of the aerosol layer.

[0360] 35. The computer implemented method of claim 34, wherein one or more of the one or more sensor arrays are implemented by a network of balloons and launch sites configured to perform the particle number density measurements and / or their radiative properties estimations.

[0361] 36. The computer implemented method of claim 29, wherein one or more of the one or more sensor arrays are implemented by long -endurance stratospheric airships and / or drones configured to measure particle number density and / or radiative properties of the aerosol layer, the number of platforms and their spatial-temporal distribution being optimized for effective control loop operation.

[0362] 37. The computer implemented method of claim 29, wherein one or more of the one or more sensor arrays comprise LIDAR measurement systems.

[0363] 38. The computer implemented method of claim 37, wherein the LIDAR measurement system comprise satellite-based LIDAR and / or ground-based LIDAR networks, configured to measure aerosol layer characteristics using background subtraction algorithms to distinguish deployed particles from ambient stratospheric aerosols.

[0364] 39. The computer implemented method of claim 29, wherein one or more of the one or more sensor arrays comprise systems configured to measure thermal emission from deployed aerosol particles while reducing background interference by exploiting unique spectral absorption characteristics of the deployed particles.

[0365] 40. The computer implemented method of claim 29, wherein one or more of the one or more sensor arrays comprise systems configured to measure top-of-atmosphere radiative fields using Earth-observation satellites equipped with radiative -flux measurement capabilities.

[0366] 41. The computer implemented method of claim 29, wherein one or more of the one or more sensor arrays comprise systems configured to measure oceanic heat balance to support estimation of the climatic response to the aerosol layer.

[0367] 42. The computer implemented method of claim 16, further comprising the step of generating warnings when deviations from intended effects or expected temporal dynamics are detected.

[0368] 43. The computer implemented method of claim 42, wherein the warnings are based at least in part on identifying and quantifying perturbations to stratospheric ozone, halogen-containing species, nitrogen oxides, and / or sulfates using one or more of microwaveP-635226-PClimb sounding, solar occultation, infrared limb emission measurements, ozonesondes, aerosol optical depth, particle counting, and spectroscopy.

[0369] 44. The computer implemented method of claim 43, wherein the estimation of stratospheric compositional perturbations is compared to and / or calibrated against controlled aerial chemical perturbation tests using contained experiments and / or controlled particledispersal experiments.

[0370] 45. The computer implemented method of claim 16, further comprising the step of constraining particle coagulation rates by measuring particle collection optical spectrometry and / or depolarization signals using LIDAR.

[0371] 46. The computer implemented method of claim 16, wherein said step (c) of receiving measured data indicative of one or more characteristics of the deployed reflective aerosol layer comprises the step of receiving measured data from particles marked with identifiable characteristics attributable to their source of dispersal.

[0372] 47. The computer implemented method of claim 46, wherein the identifiable characteristics used for particle marking comprise one or more of engineered color centers, point defects, isotopic signatures, trace-element markers, or combinations thereof.

[0373] 48. The computer implemented method of claim 46, wherein marked particles are measured and identified using mass spectrometry techniques employing laserablation or plasma ionization sources.

[0374] 49. The computer implemented method of claim 46, wherein the marked particles are measured and identified in situ.

[0375] 50. The computer implemented method of claim 46, wherein marked particles collected from the atmosphere are analyzed using one or more of Time-of-Flight Secondary Ion Mass Spectrometry, Inductively Coupled Plasma Mass Spectrometry, Scanning Electron Microscopy, and Energy Dispersive X-ray Spectroscopy.

[0376] 51. The computer implemented method of claim 46, wherein marked particles detected in the troposphere or at the Earth’s surface are used to validate and calibrate predictive models of particle transport, interactions, and atmospheric modification.

[0377] 52. A method which utilizes a solar radiation management (SRM) strategy by use of stratospheric aerosol injection (SAI) of reflective particles, the method comprising: designing an SAI architecture to achieve a desired climate response to a desired climate state, wherein the SAI architecture encompasses a choice of injected particles, and temporal dependent injection characteristics such as quantities of injection and injection locations in the stratosphere, designing an injection strategy to achieve a spatio - temporal layer of reflective particles in the stratosphere, whose associated radiative forcing drives a desired change in theP-635226-PCglobal radiative forcing which, in turn, drives the climatic response to the desired climatic state, measuring, by indirect methods, the effective radiative forcing of the particle layer by monitoring climatic variables such as radiation fields and temperatures, measuring a climatic response by monitoring climatic variables by indirect methods including at least one of radiation fields, temperatures and precipitation, devising a feedback mechanism to adjust the SAI architecture in response to the measured radiative forcing and the measured climatic response, and accompanying the SAI program by a monitoring program for climatic variables, before and after the deployment of the SAI program - to provide information which allows to constrain the prediction and the feedback algorithm being used.

[0378] 53. The method of claim 52, wherein the desired climate state corresponds to at least a partial reversal of the climatic effects of anthropogenic greenhouse gases (GHG).

[0379] 54. The method of claim 52, wherein the desired climate state is associated with a desired, either measured or deduced, spatial-temporal distribution of the global radiative forcing, separated into its longwave and shortwave contributions.

[0380] 55. The method of claim 52, further comprising adjusting the radiative forcing by modifying its shortwave and longwave components via the reflective and absorptive properties of the injected particles.

[0381] 56. The method of claim 52, wherein the configuring of the SAI comprises deriving and implementing a global spatial-temporal distribution of the reflective particles, optimized to yield radiative forcing changes that achieve the desired climatic condition.

[0382] 57. The method of claim 52, further comprising adjusting the global spatial-temporal distribution based on the monitoring of climate variables which provide information on the actual global radiative forcing and the actual climatic response.

[0383] 58. The method of claim 52, wherein the climatic response is measured by monitoring the properties of the injected particles throughout their lifecycle.

[0384] 59. The method of claim 52, wherein the climatic response is measured by monitoring the stratosphere for changes in temperature profile and / or possible interactions of the reflective particles.

[0385] 60. The method of claim 52, wherein the climatic response is measured by monitoring the troposphere, earth’s surface and the oceans for changes in climatic variables and / or possible interactions of the reflective particles.

[0386] 61. The method of claim 52, wherein the reflective particles are tagged to allow for direct measurement of their spatial-temporal distribution.

[0387] 62. The method of claim 61, wherein the tagging comprises at least one of:P-635226-PC

[0388] metal traces comprising at least one of Ca, Zn, Sr, Fe, Cu, Al, at amounts between a few ppm and a few tens of ppm, stable isotopes selected from at least one of: 29Si, 13C, 2H, 180, 42Ca, 43Ca, 44Ca, and 46Ca, and / or luminescent transition metal cations such as Eu complexes and / or strontium aluminates as fluorescent materials.

[0389] 63. The method of claim 52, wherein the monitoring allows to quantify and constrain the contributions of the anthropogenic GHGs radiative forcing, and the radiative forcing associated with the SAI, and thus provide information regarding the difference between the desired and the actual radiative forcing.

[0390] 64. The method of claim 52, wherein the difference between the desired and actual radiative forcing can be used to estimate the consequential deviation of the climatic state from the desired climatic state.

[0391] 65. The method of claim 52, wherein the monitoring program provides information regarding the actual deviations of climatic variables from their desired values.

[0392] 66. The method of claim 52, wherein the desired radiative forcing closely mimics (with opposite sign) the spatio-temporal distribution of the anthropogenic GHG contribution to the radiative forcing.

[0393] 67. The method of claim 52, further comprising improving the accuracy of the models which are being used to determine the SAI configuration for better predictability of the SAI configuration, where the measurement data is provided by the monitoring program, which is used to constrain and minimize the model uncertainties related to the longwave and shortwave contributions to the radiative forcing.

[0394] 68. The method of claim 52, further comprising improving the accuracy of the models which are being used to determine the SAI configuration for better predictability of the SAI configuration, where the measurement data is provided by the monitoring program, which is used to constrain and minimize the model uncertainties related to the deviations of climatic variables from their desired values.

[0395] 69. The method of claim 68, wherein the validation process is used to adjust the models if required, thus minimizing and constraining the uncertainties associated with the optimal SAI strategy.

[0396] In the above description, an embodiment is an example or implementation of the invention. The various appearances of "one embodiment”, "an embodiment", "certain embodiments" or "some embodiments" do not necessarily all refer to the same embodiments. Although various features of the invention may be described in the context of a single embodiment, the features may also be provided separately or in any suitable combination.P-635226-PCConversely, although the invention may be described herein in the context of separate embodiments for clarity, the invention may also be implemented in a single embodiment. Certain embodiments of the invention may include features from different embodiments disclosed above, and certain embodiments may incorporate elements from other embodiments disclosed above. The disclosure of elements of the invention in the context of a specific embodiment is not to be taken as limiting their use in the specific embodiment alone. Furthermore, it is to be understood that the invention can be carried out or practiced in various ways and that the invention can be implemented in certain embodiments other than the ones outlined in the description above.

[0397] The invention is not limited to those diagrams or to the corresponding descriptions. For example, flow need not move through each illustrated box or state, or in exactly the same order as illustrated and described. Meanings of technical and scientific terms used herein are to be commonly understood as by one of ordinary skill in the art to which the invention belongs, unless otherwise defined. While the invention has been described with respect to a limited number of embodiments, these should not be construed as limitations on the scope of the invention, but rather as exemplifications of some of the preferred embodiments. Other possible variations, modifications, and applications are also within the scope of the invention. Accordingly, the scope of the invention should not be limited by what has thus far been described, but by the appended claims and their legal equivalents.

Claims

P-635226-PCCLAIMSWe Claim:

1. An aerial dispersal system configured to disperse particles to the atmosphere from an aerial platform, the system comprising:a feeder configured to transport a powder comprising a plurality of particles; and a dispersal mechanism configured to receive and disperse the powder from the aerial platform, the dispersal mechanism further configured to receive at least one of compressed air and energy from the aerial platform, the at least one of compressed air and energy deagglomerating the plurality of particles in the powder prior to being dispersed from the aerial platform to the atmosphere.

2. The aerial dispersal system of claim 1, wherein the plurality of particles are deagglomerated as a result of exposure to at least one of high-shear turbulent flow and drag forces from accelerating flow within the dispersal mechanism.

3. The aerial dispersal system of claim 2, further comprising at least one venturi duct and flow constriction configured to accelerate the flow.

4. The aerial dispersal system of claim 1, further comprising an inlet in the aerial platform for receiving ram air generated by forward motion of the aerial platform, the ram air at least in part supplying the air or energy for deagglomeration.

5. The aerial dispersal system of claim 1, further comprising at least one of an air compressor, an air-gas turbine and pressurized air containers onboard the platform for supplying the compressed air.P-635226-PC6. The aerial dispersal system of claim 1, further comprising one or more powder storage vessels for storing the powder inside the aerial platform, the feeder configured to transfer the powder from the one or more powder storage vessels.

7. The aerial dispersal system of claim 6, further comprising one or more conveyors for conveying the powder from the feeder to the dispersal mechanism.

8. The aerial dispersal system of claim 7, wherein the one or more conveyors are configured to operate by negative pressure, positive pressure, or by a conveyor belt.

9. The aerial dispersal system of claim 1, wherein the dispersal mechanism comprises a discharge orifice through which the deagglomerated particles are dispersed to the atmosphere.

10. The aerial dispersal system of claim 1, wherein the feeder operates by at least one of gravity and negative pressure.

11. The aerial dispersal system of claim 1, wherein the feeder comprises a feeding aid configured to fluidize the powder using at least one of a fluidizing element and a vibration element.

12. The aerial dispersal system of claim 1, wherein the feeder operates to transfer the powder by negative pressure, and wherein the feeder comprises a dosing mechanism to control the negative pressure.

13. The aerial dispersal system of claim 12, wherein the dosing mechanism comprises at least one of a rotary valve, a pinch valve, a butterfly valve, and a gate valve.P-635226-PC14. The aerial dispersal system of claim 13, further comprising a restraint for mitigating against spontaneous escape of the powder from the aerial platform.

15. The aerial dispersal system of claim 1, further comprising a purge mechanism for dislodging stuck powder from all portions of the dispersal system that house or transport the powder.

16. The aerial dispersal system of claim 15, wherein the purge mechanism operates using compressed air to dislodge stuck powder.

17. The aerial dispersal system of claim 1, wherein the feeder comprises a sensor and control mechanism configured to determine how much powder remains in the feeder and how much powder is being dispersed from the feeder overtime.

18. The aerial dispersal system of claim 17, wherein the sensor and control mechanism comprise at least one of a weighing scale and a powder surface level sensor.

19. The aerial dispersal system of claim 1, further comprising an eductor using a pressure difference to mix the powder with the compressed air to deagglomerate particle aggregations in the powder.

20. The aerial dispersal system of claim 1, further comprising at least two eductors with an intermediate container, which together are configured to deagglomerate particle aggregations in the powder.

21. The aerial dispersal system of claim 1 , further comprising at least one deagglomeration target configured to receive the powder, the target comprising at least one of a direct-impact surface and a mesh structure.P-635226-PC22. The aerial dispersal system of claim 1, configured to store an amount of powder within a fuselage of the aerial platform and to disperse the amount of powder using at least one of compressed air and energy supplied from onboard systems of the aerial platform.

23. The aerial dispersal system of claim 1, wherein the compressed air is generated onboard the platform, including one of air bled from turbine engines and ram air supplied through platform inlets.

24. The aerial dispersal system of any one of claim 23, further comprising a turbine engine configured to provide compressed air at a required flow rate, temperature, and pressure for the dispersal mechanism.

25. The aerial dispersal system of claim 1, configured to direct air from outside the aerial platform through the dispersal system with minimal drag and energy loss, including by minimizing pressure losses in an air inlet for receiving ram air and in one or more components that compress air.

26. The aerial dispersal system of claim 25, further configured to increase thrust generated by discharge of the air and dispersed particles from the aerial platform.

27. The aerial dispersal system of claim 1, wherein a center of gravity of the aerial platform is maintained within allowable limits by at least one of controlling fuel mass distribution among fuel tanks and controlling powder mass distribution within the storage vessels.

28. The aerial dispersal system of claim 1, wherein unused fuel-tank volume of the aerial platform is configured for use to store the powder.P-635226-PC29. The aerial dispersal system of claim 1, wherein the fuselage of the aerial platform is modified to operate with a partially pressurized or unpressurized cabin that houses the dispersal system to reduce weight and / or energy requirements.

30. The aerial dispersal system of claim 1, configured to disperse at least one ton of particles per flight of the aerial platform.

31. The aerial dispersal system of claim 1, further comprising at least one sensor configured to monitor one or more of powder dispersal rate, particle size distribution, and particle electric charge distribution.

32. The aerial dispersal system of claim 1, wherein the particles comprise one or more of particles of at least one of: amorphous silica particles, calcium carbonate particles, core-shell particles comprising one or more of silica, calcium carbonate - including its amorphous form (ACC) and its crystalline polymorphs calcite, vaterite, aragonite - hydroxyapatite, magnesium calcite, zirconia oxide, gypsum, magnesium carbonate, unspecific magnesite, dolomite, mixtures of calcium carbonate and magnesium carbonate, calcium alginate, maltodextrin and calcium sulfate dihydrate, where the particles may have a hydrophobic and / or unreactive coating.

33. The aerial dispersal system of claim 1, wherein the particles comprise an outer surface configured for minimizing interparticle cohesive forces.

34. The aerial dispersal system of claim 1, wherein the particles comprise an outer surface configured to minimize energy requirements for deagglomeration.

35. The aerial dispersal system of claim 1, configured to disperse the particles at a rate of at least 1 tons per hour using compressed air at a throughput of at least 1 standard cubic meter per second.P-635226-PC36. The aerial dispersal system of claim 1, wherein the feeder and dispersal mechanism are configured within Unit Load Device (ULD) containers standardized for aircraft loading, transport, and unloading.

37. The aerial dispersal system of claim 1, wherein the compressed air is modulated or pulsed to achieve agglomeration while reducing the amount of compressed air required for dispersal of the particles.

38. The aerial dispersal system of claim 1, wherein the deagglomeration mechanism is configured to optimize deagglomeration of agglomerates of submicron particles by inducing at least one of: fine-scale turbulent eddies, high turbulent dissipation rates, rapid flow acceleration / deceleration, particle trajectories maximizing the residence time in regions of high turbulent shear and / or particle trajectories maximizing collisions between particles and surfaces and / or other particles.

39. The aerial dispersal system of claim 38, wherein the particle trajectories are tailored by manipulating the local air velocity in relation to the Stokes number of particle aggregates using at least one of: geometrical protrusions or corrugations enhancing turbulence and mixing, turns and / or bends and / or flow combining elements.

40. The aerial dispersal system of claim 1, wherein the deagglomeration mechanism is configured to break down agglomerates by applying pressure gradients and / or rapid acceleration by passing the flow through shock waves.

41. The aerial dispersal system of claim 1, wherein the powder is first aerated before conveying.P-635226-PC42. The aerial dispersal system of claim 1, wherein powder conveying and / or deagglomeration are aided by the addition of at least one of anti-caking agents and flowenhancing additives.

43. The aerial dispersal system of claim 1, wherein larger agglomerates of the powder are initially broken down by a milling mechanism.

44. The aerial dispersal system of claim 1, further comprising multiple hoppers containing particles with different internal markings and a switching mechanism configured to enable selective dispersal from each hopper, wherein the different internal markings enable at least one of tracking, monitoring and governance of the plurality of particles after dispersion of the plurality of particles in the atmosphere, and wherein the markers are present in amounts sufficient for detection by analytical techniques.

45. An aerial dispersal system configured to disperse particles to the atmosphere from an aerial platform, the system comprising:a feeder configured to transport a powder comprising a plurality of particles; and a dispersal mechanism configured to receive and disperse the powder from the aerial platform, the dispersal mechanism generating an electric charge on the plurality of particles to electrostatically repel the particles from one another to prevent agglomeration.

46. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated by triboelectric charging resulting from frictional engagement between the particles and interior wall surfaces of the dispersal mechanism.

47. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated and / or mediated by triboelectric charging resulting from frictional engagement between the particles.P-635226-PC48. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated by corona discharge.

49. The aerial dispersal system of claim 48, further comprising at least one corona discharge electrode configured to generate ions that impart electric charge to the particles.

50. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated by dedicated triboelectric charging.

51. The aerial dispersal system of claim 50, further comprising at least one of a triboelectric charging region having an interior surface configured to increase frictional interaction with the particles.52 The aerial dispersal system of claim 51, wherein the interior surface is configured to increase frictional interaction with the particles by providing material of the surface interior with a substantially different electron affinity than the particles and / or particle surfaces.

53. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated by electrostatic induction.

54. The aerial dispersal system of claim 53, further comprising at least one pair of induction electrodes configured to establish an electric field that induces charge on the particles.

55. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated by mixing the particles with ionized air.P-635226-PC56. The aerial dispersal system of claim 55, further comprising at least one ionizing element configured to ionize compressed air upstream of the dispersal mechanism.

57. The aerial dispersal system of claim 45, wherein the electric charge on the plurality of particles is generated and / or mediated between particles by exposure to high-shear turbulent flow within the dispersal mechanism.

58. The aerial dispersal system of claim 45, further comprising at least one charging component located downstream of the discharge orifice that is configured to add electric charge on the plurality of particles after their release.

59. An airborne chemical characterization system for measuring the interaction between particles and the atmospheric air, without releasing particles into the environment, the system comprising:an aerial platform configured for sustained flight at altitudes of interest;a real-time air sampling system within the aerial platform comprising at least one sampling tube configured to continuously collect atmospheric air at ambient temperature and pressure conditions;a sealed reaction chamber positioned within the aerial platform; a controlled particle introduction assembly comprising at least one of: (i) an injection system configured to introduce aerosolized particles into the sealed reaction chamber for interaction with the collected air; or (ii) a coating of particles deposited on an internal surface of the reaction chamber or on a surface of interchangeable inserts positioned within the reaction chamber; anda real-time in-situ analytical detection system configured to monitor chemical interactions, reaction kinetics, and / or particle behavior without any release of materials to the external environment.P-635226-PC60. The airborne chemical characterization system of claim 59, wherein the real-time analytical detection system comprises at least one of: a Chemical Ionization Mass Spectrometry (QMS) system configured for sensitive in-flight quantification of atmospheric components and / or reaction products, a Single-Particle Mass Spectrometry (SPMS) system configured for sensitive in-flight characterization and quantification of ambient and / or introduced particles, tunable diode laser absorption spectroscopy systems configured for species-specific detection of trace gases, and additional particle size and composition analyzers configured to monitor changes in test particle characteristics during controlled exposure to sampled air.

61. The airborne chemical characterization system of any one of claims 59, further comprising at least one of: a containment and collection system configured to capture test particles and / or reaction products for post-flight analysis, multiple interchangeable reaction chambers enabling testing of different particle samples during a single flight mission, and environmental parameter monitoring systems configured to record at least one parameter of temperature, pressure, and humidity during particle interaction studies.

62. A method of dispersing particles from an airplane, the method comprising controllably dispersing the particles from the airplane out into the stratosphere using energy and compressed air provided from the airplane, wherein the particles are fed for dispersal as a powder and wherein the particles are configured to have diameters between 0.05pm and 10pm and to not agglomerate.

63. The method of claim 62, further comprising:conveying the powder to be fed for dispersal,feeding the powder by gravity or by negative pressure while dosing, sensing and controlling the feed, anddeagglomerating the powder.

64. The method of claim 63, wherein the feeding of the powder is caried out by gravity and further comprising fluidizing the powder prior to the feeding.

65. The method of claim 64, wherein the deagglomerating of the powder is carried out by one or more of negative pressure and by impinging the powder onto a target.P-635226-PC66. The method of claim 63, wherein the conveying of the powder is carried out by negative pressure.

67. The method of claim 62, further comprising monitoring the particles immediately after their dispersal.

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