202 results about "Dynamic light scattering" patented technology

The invention discloses an LED street lamp multi-scene intelligent regulation and control method and system for road illumination. The method comprises the steps that environment sensing parameters and equipment state parameters are collected; constructing a dynamic light scattering model according to the environment perception parameters and the equipment state parameters, predicting effective illumination distribution from the LED light source to the road surface in the current environment, and generating an LED spectrum compensation strategy; the real value of effective illumination distribution from the LED light source to the road surface is monitored in real time, the deviation between the real value and a predicted value is analyzed, and if the deviation exceeds a preset threshold value, the light attenuation coefficient, the road surface equivalent reflectivity and the LED working temperature are calculated in a reverse iteration mode according to the deviation so as to update the LED spectrum compensation strategy; and generating a PWM (Pulse Width Modulation) driving signal according to the updated LED spectrum compensation strategy, controlling the duty ratio of each sub light source in the LED array, and dynamically adjusting the LED spectrum distribution. According to the method, the LED operation parameters are dynamically regulated and controlled through the deviation between the true value and the predicted value of the effective illumination distribution, the light attenuation is compensated in real time, the spectral efficiency is optimized, and the LED power consumption is reduced on the premise of ensuring the illumination quality.

The invention discloses a particle size measuring device based on combination of a dynamic light scattering method and a sedimentation method and a measuring method thereof. The particle size measuring device comprises a laser, a light intensity adjusting unit, a sample pool, a thermostatic bath, a PD detector, an optical fiber head, an APD detector, a data acquisition unit, a PC and a control unit. The laser emits incident laser, the incident laser passes through the light intensity adjusting unit, penetrates through the sample cell and a sample and then enters the PD detector, and a transmission light signal is collected through the data acquisition unit and transmitted to software for calculating the particle size and concentration of settled large particles; scattered light is received by an optical fiber head with a fixed angle of 90 degrees or 160-175 degrees and is converted into a digital signal by an APD detector, and the digital signal enters a data acquisition unit and is transmitted to software for calculating the particle size of particles in a non-settling nanometer range. According to the technical scheme provided by the invention, the particle size distribution information of the wide-distribution particle dispersion system in a nano-micron range can be measured in a testing process.

The invention discloses a vector flow velocity measuring device and method based on a bidirectional scanning spectral domain optical coherence tomography technology. Comprising a super light-emitting diode light source, an optical fiber coupler, a polarization controller, an interferometer comprising a sample arm and a reference arm, and a collimating lens, the collimating lens, the grating, the focusing lens group and the linear array camera are sequentially connected through a light path; the linear array camera, the computer and the two-dimensional galvanometer are sequentially connected through a line; according to the method, the fixed bias vector velocity is introduced by utilizing the bidirectional scanning technology, the dynamic light scattering optical coherence tomography method and the Doppler optical coherence tomography method are combined, decoupling of each parameter of the vector flow velocity is efficiently and accurately realized, and a quantitative index is provided for vector flow velocity analysis. The vector flow velocity measuring device based on the bidirectional scanning spectral domain optical coherence tomography technology is simple in system setting and low in cost, the time resolution is improved by about 2.5 times, and the measuring time is shorter.

The invention provides a contact lens with peripheral defocus, and relates to the technical field of optical lenses, the lens comprises a contact optimization core area, a partitioned progressive microprism array area and a dynamic light scattering area, and the specific setting is as follows: the contact optimization core area is located at the geometric center of the lens, the outward extension radius is 1.8-2.2 mm, and the contact optimization core area provides clear central vision; according to the intelligent self-adaptive contact lens, the intelligent self-adaptive contact lens is characterized in that the intelligent self-adaptive contact lens comprises a contact optimization core area and a partition progressive microprism array area, the partition progressive microprism array area is located on the outer side of the contact optimization core area and surrounds the contact optimization core area in a concentric ring shape, and through collaborative design of the partition progressive microprism array area and the dynamic light scattering area, the real-time monitoring and dynamic adjusting capacity of a photoelectric feedback control module is combined; the problem that an optical structure of an existing product lacks dynamic adaptability is effectively solved, and the optical structure can be changed according to different illumination environments and wearing duration.

The invention provides molybdenum sulfide powder, a heavy metal adsorbent, a photo-thermal conversion material, a distillation method, an oxygen reduction catalyst and catalyst ink. This molybdenum sulfide powder contains a 3R crystal structure of molybdenum disulfide. The heavy metal adsorbent according to the present invention contains molybdenum sulfide particles having a median diameter (D50) of 10-1000 nm as determined by a dynamic light scattering type particle size distribution measurement device. This photo-thermal conversion material contains a material containing molybdenum sulfide particles, and generates heat by absorbing light energy.

The invention discloses a multi-technology combined medication analysis platform of an oligonucleotide drug, which relates to the technical field of drug analysis and is technically characterized by comprising an oligonucleotide drug delivery technology module, a liposome, a polymer nanoparticle or an exosome is selected as a delivery carrier, the surface of the delivery carrier is modified with hydrophilic polyethylene glycol or a targeting ligand, and the oligonucleotide drug delivery technology module is connected with the oligonucleotide drug delivery module. The performance of the material is represented by dynamic light scattering and a transmission electron microscope; the multi-technology platform analysis module integrates RT-qPCR, LC-FL, LC-MS / MS and LC-HRMS technologies, is respectively used for target gene expression quantification, drug distribution tracking, drug principal component quantification and metabolite structure analysis, establishes a cross validation rule, and requires a correlation coefficient R2gt of an LC-MS / MS quantitative result and RT-qPCR expression data; 0.95%, 0.95%; the pharmacokinetic evaluation module constructs a PBPK model to predict human pharmacokinetic parameters, and draws a drug metabolism network diagram in combination with an LC-HRMS metabolite identification result; by integrating various advanced analysis technologies, the problems of low sensitivity, poor specificity and difficult metabolite analysis in the prior art are solved.

The present invention belongs to the technical field of chemical engineering, and specifically provides a chemical mechanical polishing (CMP) composition and CMP method for a silicon carbide substrate. The composition includes abrasive alumina particles, an oxidizing agent and clay, wherein in the composition, the abrasive particles have a negative zeta potential at a pH of 7.5 to 9.5, and the clay has a z-average size of 1 nm to 20 μm measured by dynamic light scattering. The CMP composition provided by the present invention can improve the polishing effect on the silicon carbide substrate, and can achieve good recirculation performance and a low number of surface defects while obtaining a high material removal rate and low surface roughness.

Disclosed in the present invention are an optical apparatus for measuring a nanoparticle concentration and a measurement method thereof. The optical apparatus comprises a sample cell, a rotary wheel installed with a neutral-density filter, an APD detector, a PD detector, a laser device, a lens, a data acquisition card and a control unit, wherein a laser emitted by the laser device passes through the lens to illuminate a sample in the sample cell; in a transmission direction, the intensity of the transmitted laser is measured by means of the PD detector; and a scattered signal from the sample is accepted at a 90° or in a backward direction by the APD detector connected to an optical fiber. The measurement method comprises: measuring a volume fraction Φ of a sample by means of a transmitted laser intensity signal and a light extinction method; measuring a particle size distribution of the sample by means of a scattered laser signal and a dynamic light scattering method; and calculating a volume fraction Φi and a number concentration of each particle size peak by means of the volume fraction Φ and the particle size distribution. The present invention combines a light extinction method and a dynamic light scattering method to implement the measurement of both a volume concentration and a number concentration of a sample.

The invention provides a preparation method of an exosome antibody microsphere conjugate, which belongs to the technical field of exosomes, and comprises the following steps: preparing a carboxyl polystyrene microsphere suspension with the particle size of 50 nanometers, and ensuring that the size of the microsphere is stabilized in a range of 50 + / -5 nanometers by optimizing centrifugation and cross-linking conditions. And then coupling the exosome marker antibody with the microspheres, and closing unreacted active groups. A mathematical model is adopted to optimize purification process parameters for purification. A dynamic light scattering and transmission electron microscope is utilized to characterize coupling physics properties, and a conjugate meeting requirements is screened. And finally, obtaining fluffy porous exosome antibody microsphere conjugate freeze-dried powder under the protection of a sucrose solution by adopting a vacuum freeze-drying method. The method solves the technical problems that in an existing exosome microsphere conjugate preparation process, centrifugation and purification parameters are often set according to artificial experience, optimization is difficult to obtain, and the quality of the exosome microsphere conjugate is affected.

The invention provides an extracellular vesicle marker separation-free detection method based on nanoparticle enhancement, and belongs to the technical field of detection methods, the method comprises the following steps: preparing gold nanoparticles with the surface modified with a first antibody, the first antibody being used for specific recognition of an extracellular vesicle surface marker; determining the particle size distribution of the gold nanoparticles by adopting a dynamic light scattering method, and determining the surface potentials and surface isoelectric points of the gold nanoparticles by adopting a potentiostat; adopting a transmission electron microscope to characterize the morphology of the screened gold nanoparticles; co-modifying polyethylene glycol molecules on the surfaces of the gold nanoparticles to form an anti-interference layer; mixing the gold nanoparticles with uniform morphology with a sample to be detected; adding a second antibody into the mixed system; distinguishing signals of the binding-state second antibody and the free-state second antibody through fluorescence lifetime analysis; preparing an extracellular vesicle standard substance, and obtaining a standard curve and a system response curve; the optimal detection condition is determined by solving the detection system optimization equation set, and separation-free detection is carried out.

This method for producing a metal carbide is a method for producing a powder-shaped metal carbide using a complex polymerization method, the method comprising: a complexing step for mixing a metal hydroxide and a basic compound to produce a first mixed solution, adding hydrogen peroxide to the first mixed solution to produce a second mixed solution, and reacting the first mixed solution with the second mixed solution; adding an organic acid to the second mixed solution to generate a metal carbide precursor; a carbonization step for generating a metal carbide by firing the metal carbide precursor; and a pulverization step in which the metal carbide is pulverized to form a metal carbonized powder. The metal carbide powder according to the present invention has a specific surface area of 1 m2 / g or more and a roundness of 0.78 or more as determined by a BET method. Furthermore, the metal carbide intermediate dispersion of the present invention comprises a metal compound, a basic compound, hydrogen peroxide, and an organic acid, and the particle diameter (D50) of particles in the metal carbide intermediate dispersion as determined by particle diameter distribution measurement using a dynamic light scattering method is 1,000 nm or less.

The invention provides selenium nanoparticles as well as a preparation method and application thereof, and belongs to the technical field of selenium nanoparticles. Acetone ultrasonic cleaning and chemical polishing pretreatment are performed on a pure titanium substrate to obtain a clean surface, an anodic oxidation method is adopted to prepare a # imgabs0 # nanotube array carrier, and the nano-particles are prepared into selenium nano-particles. The method comprises the following steps: accurately depositing selenium nanoparticles on a carrier by using an electrochemical deposition method, realizing load control by combining an electrochemical kinetics principle, realizing uniform dispersion of the particles by matching an ultrasonic dispersion technology with a particle swarm optimization algorithm, and carrying out centrifugal separation and vacuum drying to obtain a spherical selenium nanoparticle product. And a multi-dimensional quality control detection system of a transmission electron microscope, an X-ray photoelectron spectroscopy and dynamic light scattering is established, so that the technical problems that the particle size distribution is non-uniform and the deposition load is difficult to accurately control in the preparation process of the selenium nanoparticles are solved.

The invention discloses a calcium hydroxide and industrial wastewater co-treatment method, and relates to the technical field of environmental engineering, and the method comprises the following steps: S100, adopting global dynamic light scattering and electromotive force imaging combined monitoring, and monitoring surface charge change and particle size evolution of nanoparticles in industrial wastewater in a calcium hydroxide adding process in real time, and extracting a dynamic threshold index of dispersion stability mutation. According to the invention, a dispersion stability threshold is extracted through dynamic light scattering and electromotive force imaging, a particle dispersion risk index is constructed, real-time evaluation of aggregation failure of nanoparticles and dynamic prediction of a feeding strategy are realized, linkage feeding of a chelating organic polyamine flocculant is combined, bridging and surface energy mutation are blocked, and stability of charges and particle sizes is maintained. By means of closed-loop feedback and on-line early warning, the adding proportion is optimized, the gathering and settling efficiency is improved, membrane pollution and filtering blockage are reduced, and the stability and economical efficiency of wastewater treatment are improved.

The present invention discloses a method for measuring the three-dimensional distribution of the particle size of nanoparticles in a solution: irradiating the nanoparticles with a laser beam, and the scattered light formed interferes with a reference light modulated by an optical path to form holographic interference fringes, which are recorded on a camera to obtain a digital hologram of the nanoparticles; performing three-dimensional reconstruction on the digital hologram to obtain a focused image of the nanoparticles; and obtaining the particle size of the nanoparticles based on the scattered signal in the focused image, the principle of dynamic light scattering, and the correlation between the particle size and the diffusion coefficient of the nanoparticles. The present invention also discloses an apparatus for measuring the three-dimensional distribution of the particle size of nanoparticles in a solution: a signal emission unit, including a continuous laser and an optical path adjustment section; a signal receiving unit, including a camera for recording the holographic interference fringes; and a signal processing unit, connected after the signal receiving unit, for processing the digital hologram of the nanoparticles. The method and the apparatus achieve in-situ measurement of the instantaneous particle size distribution of nanoparticles at three-dimensional positions in a sample cell.

The invention discloses a tumor ultrasonic image sensitivity detection method, and relates to the technical field of tumor ultrasonic imaging. Comprising the following steps: S1, preparing tumor balls for simulating tumors, and forming the tumor balls in a complete culture medium containing matrigel by using a 4T1 breast cancer cell strain through a suspension culture method; according to the method, 4T1 breast cancer cell tumor spheres with different sizes are accurately prepared, the sizes of nano and micron contrast agents are detected by utilizing a dynamic light scattering technology, the accuracy and reliability of an experiment are ensured, the penetration condition of a contrast material in the tumor spheres can be intuitively evaluated through penetration detection of a laser confocal microscope, and the accuracy and reliability of the experiment are ensured. Through combination of ultrasonic imaging and ultrasonic quantification software, the gray value of the region of interest is accurately quantified, and accurate data is provided for subsequent statistical analysis; in addition, unidirectional variance analysis is carried out through Graphpad software, the sensitivity difference of ultrasonic images under different conditions can be scientifically evaluated, a powerful basis is provided for early diagnosis and treatment of tumors, and the method has a wide application prospect.

A temperature verification device for checking the accuracy of a temperature sensor of a dynamic light scattering instrument, the temperature verification device comprising: a body configured to be received in a sample cell holder; and the calibration temperature sensor is positioned in the main body at a position corresponding to the scattering volume of the dynamic light scattering instrument.

The invention relates to the technical field of tire detection, in particular to a white carbon black dispersity identification method and system based on dynamic light scattering and small-angle X-ray scattering combined analysis. According to the method, the dispersity of the white carbon black is comprehensively evaluated by measuring the particle size distribution and the aggregation degree of white carbon black particles in the composite material and combining the average particle size and the particle size distribution width of a DLS test and the diffraction peak intensity and the diffraction peak width of an SAXS test. According to a test result, a dispersity scoring standard is formulated: the score is 0-10 when the dispersity is good, the score is 10-20 generally, and the score is greater than 20 when the dispersity is poor. The method provided by the invention has relatively high test efficiency, accuracy and operability, and is suitable for conventional detection in industrial production. Experiments prove that the method shows good accuracy and reliability in practical application, and the performance of rubber products can be effectively improved, especially in the fields with high requirements such as tire manufacturing.

The invention relates to the technical field of biology, and discloses a nano composite probe as well as a preparation method and application thereof. The nano composite probe comprises an iron-based metal organic framework, glucose oxidase loaded on the surface of the iron-based metal organic framework, and an anti-cTnI antibody coupled with the glucose oxidase. According to the nano-composite probe, glucose oxidase, an acid-responsive iron-based metal organic framework and a detection antibody are subjected to function integration, so that three-in-one of recognition, driving and feedback is realized; a cardiac troponin I detection method based on a nanoprobe triggered enzyme catalysis-MOF disintegration-Fenton reaction self-amplification cascade system innovatively adopts a strategy of etching a DNA protective layer by hydroxyl radicals to regulate and control gold nanoparticle salt-induced aggregation, and finally reads signals through dynamic light scattering, so that ultrahigh-sensitivity detection is realized, the detection limit is as low as 1.5 * 10 <-13 > g / mL, and the detection time is greatly shortened. The stability and the specificity are excellent.

The utility model discloses a particle size measuring device based on combination of a dynamic light scattering method and a sedimentation method. The particle size measuring device comprises a laser, a light intensity adjusting unit, a sample pool, a thermostatic bath, a PD detector, an optical fiber head, an APD detector, a data acquisition unit, a PC and a control unit. The laser emits incident laser, the incident laser passes through the light intensity adjusting unit, penetrates through the sample cell and a sample and then enters the PD detector, and a transmission light signal is collected through the data acquisition unit and transmitted to software for calculating the particle size and concentration of settled large particles; scattered light is received by an optical fiber head with a fixed angle of 90 degrees or 160-175 degrees and is converted into a digital signal by an APD detector, and the digital signal enters a data acquisition unit and is transmitted to software for calculating the particle size of particles in a non-settling nanometer range. According to the technical scheme provided by the utility model, the particle size distribution information of the wide-distribution particle dispersion system in a nanometer-micron order range is measured in a testing process.

This molybdenum trioxide powder has a specific surface area, as measured using the BET method, of 100 mｍ2 / g-500 m2 / g. The molybdenum trioxide powder may have a median diameter D50 of 5-1000 nm, as determined using a dynamic light scattering method. The molybdenum trioxide powder may have a purity of 99 mass% or more. The molybdenum trioxide powder may include molybdenum trioxide having a β crystal structure.

The invention discloses a hydrophobic Ru nano-particle catalyst, a preparation method and application of the hydrophobic Ru nano-particle catalyst in bisphenol A hydrogenation reaction. The catalyst is prepared by dissolving a ruthenium salt precursor, mixing the ruthenium salt precursor with a surfactant containing nitrogen, phosphorus or sulfur, and reacting through a reducing agent in an inert atmosphere. The preparation method is simple and efficient, and reduction-modification coupling is realized in one step. Different from a traditional supported Ru catalyst, active sites of the carrier-free hydrophobic Ru nanoparticle catalyst are fully exposed, the particle size distribution uniformity of nanoparticles is excellent, and the dynamic light scattering PDI is smaller than or equal to 0.19. In the bisphenol A hydrogenation reaction, the raw material conversion rate reaches 95% or above, the selectivity of the target product hydrogenated bisphenol A reaches 95% or above, the conversion rate and the selective attenuation rate are both smaller than 5% after 5 cycles, and excellent cycle stability is achieved.

A molybdenum trioxide powder, which contains an aggregate of primary particles comprising a crystal structure of molybdenum trioxide, the crystal structure comprising α-crystals having an average crystallite size of 50 nm or less. The median particle diameter D50 of the primary particles, which is obtained by a dynamic light scattering method, is 2000 nm or less. 50 is 2000 nm or less.

The invention discloses an intelligent preparation and control method for nano metal powder driven by a droplet microfluidic technology, relates to the technical field of metal powder processing, and aims to accurately control particle distribution, calculate particle size distribution uniformity Dcv and dispersion stability coefficient Dsf and optimize a shear flow field through a droplet interface dynamic model in combination with a dynamic light scattering and adaptive optimization algorithm. The particle size uniformity is ensured, the powder stacking density and the conductive stability are improved, and the problem that particle size distribution is difficult to accurately control in an existing method is solved; a high-sensitivity sensor is adopted to monitor environmental interference, Fourier transform analysis and Gaussian process regression reinforcement learning are combined to optimize temperature and flow velocity, by-products and pollutants are reduced, powder purity is ensured, long-term stability of electronic devices is improved, and resistance drift or local overheating is avoided. And aiming at the agglomeration problem, an agglomeration trend value Pag is calculated and graded evaluation is carried out, so that particle agglomeration is effectively inhibited, and the stability and reliability of the conductive material are improved.

This invention relates to aqueous sols and organic solvent sols containing highly stable hollow silica particles, and further to methods for improving the stability of the aforementioned sols, which have suffered reduced storage stability, and methods for manufacturing such sols. To this end, a hollow silica sol is provided, containing hollow silica particles with spaces within the outer shell and monovalent alkali metal ions, wherein the molar number of these monovalent alkali metal ions, converted to M₂O (M representing a monovalent alkali metal atom), is 7.12 × 10⁻⁶ moles of SiO₂ in the hollow silica particles. ‑6 ~285×10 ‑6 The sol contains hollow silica particles and monovalent alkali metal ions in a specific ratio. After being stored at 50°C for 48 hours, the average particle size measured by dynamic light scattering (DLS) is within 2.0 times that of the average particle size measured by DLS before storage. The average particle size measured by DLS is 20–150 nm. A stabilization method involves adding monovalent alkali metal ions to the hollow silica sol, where the DLS particle size value is larger than that during manufacturing, in the aforementioned ratio of monovalent alkali metal ions to SiO2 in the hollow silica particles, thereby reducing the increased DLS particle size value.

Provided is a silica sol in which silica particles are dispersed in a nitrogen-containing solvent for mixing with polyimide-based and polyamide-based polar resins in a state of good compatibility, said silica sol being capable of being subjected to additional silane treatment according to the use or the like, having excellent storage stability at a high concentration, and having both customizability and reliability. The silica sol contains silica particles having an average particle diameter of 5-100 nm obtained by a dynamic light scattering method and having an organic group containing an unsaturated bond between carbon atoms bonded to the surface, and a nitrogen-containing solvent, the amount of organic groups that are bound to the surfaces of the silica particles and that contain unsaturated bonds between carbon atoms is 0.1-2.0 per unit area of the surfaces of the silica particles, the concentration of the silica particles is 25-70 mass%, and free silanol groups are present on the surfaces of the silica particles. The amount of free silanol groups present per unit area on the surface of the silica particles is 0.4-1.2 per nm2.

Disclosed herein is a composition comprising: an epoxy-containing component, elastomeric particles in an amount of greater than 11% by weight to 25% by weight based on total weight of the composition; and a curing component activatable by an external energy source, the curing component comprising at least one guanidine having a D90 particle size of 25 μm measured by dynamic light scattering. Also disclosed is the composition in an at least partially cured state. Also disclosed is a method for treating a substrate comprising applying the composition to a surface of a substrate; and applying an external energy source to cure the composition. Also disclosed are substrates comprising the composition. Also disclosed are substrates formed by the method of the present invention.

The invention provides an extracellular vesicle surface specific marker modification method, which belongs to the field of disease marker modification, and comprises the following steps: adopting an ultracentrifugation method to separate and obtain extracellular vesicles; respectively determining the particle size distribution state, the number concentration state and the form integrity state of the extracellular vesicles by adopting a dynamic light scattering method, a nano particle tracking analysis method and a transmission electron microscope; respectively determining the surface charge state and the structural integrity state of the extracellular vesicle by adopting a surface potential analyzer and a Western Blot method; adding magnetic nanoparticles into the extracellular vesicle solution, and determining the binding efficiency state of the magnetic nanoparticles and the extracellular vesicles by adopting a magnetic resonance imaging method; carrying out separation by utilizing a magnetic field separation technology to obtain extracellular vesicles combined with the magnetic nanoparticles; the problem that the surface of an existing extracellular vesicle cannot be accurately modified can be solved.

This invention uses nano-cerium oxide as an abrasive, with a dynamic light-scattering particle size of 1-30 nm, which helps reduce scratches caused by chemical mechanical processes. The removal rates of silicon oxide, silicon nitride, and polycrystalline silicon can be controlled by selecting appropriate additives. Specifically, the ratio of silicon oxide removal rate to silicon nitride removal rate can be adjusted within the range of 2:1 to 3500:1, and the ratio of silicon oxide removal rate to polycrystalline silicon removal rate can also be adjusted within the range of 2:1 to 3500:1.

Described herein are systems and methods that obtain dynamic light scattering data from a plurality of particle samples, and in some instances, also measure the UV / Vis absorption spectrum of the particle samples. The systems and methods may characterize particles in the samples by obtaining light scattering data from multiple angles by a single rotating light detector. The data obtained in this manner may allow a greater dynamic range of particle sizing than when using a single angle.

The present invention provides a tantalic acid compound dispersion containing tantalum. The tantalic acid compound dispersion contains an organic acid and one or more elements X selected from the group consisting of alkali metal elements and / or alkaline earth metal elements. The tantalic acid compound dispersion has a D50 (on a volume integration basis) of 100 nm or less as measured by a dynamic light scattering.