292 results about "Molecular diffusion" patented technology

Medical devices, utilizing multiple reservoirs to protect and selectively expose sensors or other reservoir contents, are provided having (i) a reservoir contents destruction mechanism to interrupt the release or exposure of reservoir contents, for example, to deactivate an unneeded sensor and prevent it from negatively impacting other sensors, (ii) a protective covering material layer over the sensor underneath the reservoir cap, which protects the sensor membrane and sensor during reservoir cap disintegration and then is removed, (iii) a device design for containing sensors in shallow, wide reservoir structures to enhance sensor exposure by minimizing molecular diffusion distances, (iv) an implantable sensor unit and a separate drug delivery unit, or (v) combinations thereof.

A stent that is adapted for introduction into a body passageway and which releases at least one biological agent after being inserted in the body passageway. The release of the at least one biological agent can be a controlled release via molecular diffusion through a non-porous polymer layer.

The present invention relates to a method of preparing a microporous crystalline molecular sieve having mesoporous skeleton, comprising following steps: (a) adding a meso-SDA (meso-Structure Directing Agent) into a gel composition of synthesizing molecular sieve, (b) subjecting the mixture obtained in the above step (a) to crystallization by a hydrothermal reaction, a microwave reaction, a dry-gel synthesis, etc., and (c) removing selectively organic materials from the resulted material obtained in the above step (b) by a calcination or a chemical treatment. Molecular sieve having mesoporous skeleton synthesized by the present invention exhibits, as compared with conventional zeolite, a good molecule diffusion ability and a greatly improved catalytic activity.

The invention discloses a diesel oil hydrogenation pour point depressing method. A series flow of hydrofining and hydrogenation pour point depressing is adopted in the method, wherein a hydrogenation pour point depressing catalyst is modified by metal auxiliary agent and silicon, effectively regulates the acidity and orifice shape of the inner surface and the outer surface of a shape-selective cracking molecular sieve, is favorable for dispersing wax molecules in a diesel oil raw material into pore canals of the molecular sieve to perform shape-selective cracking reaction, and has high catalytic activity and selectivity of a target product; and because the acidity of the outer surface of the molecular sieve is weak, side reactions such as secondary cracking and the like are reduced, the pour point depressing effect of the diesel oil is good, and the fraction yield of the diesel oil is high.

A stent that is adapted for introduction into a body passageway and which releases at least one biological agent after being inserted in the body passageway. The release of the at least one biological agent can be a controlled release via molecular diffusion through a non-porous polymer layer.

The invention belongs to the catalyst technical field, in particular to a ZSM-5 zeolite catalyst characterized by high ratio of silica and alumina as well as a preparation method and the application thereof. The catalyst, taking a pure silicon compound with activity as a silicon source, is made by a hydrothermal synthesis method by adding trace aluminum. The ratio of silica and alumina in the zeolite catalyst is over 1,000, sub-micron crystal particles with open channels have large surface area and good molecular diffusivity. The catalyst in the reaction of MTP has excellent catalytic activity, high selectivity of propylene, and high ratio of propylene and ethylene. The catalyst has simple regeneration method and good restoration of performance after regeneration.

Techniques for assembling a lipid bilayer on a substantially planar solid surface are described herein. In one example, a lipid material such as a lipid suspension is deposited on a substantially planar solid surface, a bubble filled with fast diffusing gas molecules is formed on the solid surface, and the gas molecules are allowed to diffuse out of the bubble to form a lipid bilayer on the solid surface.

The invention relates to a device and method for testing molecular diffusion coefficients in a multi-component oil-gas system under high temperature and high pressure. The device consists of an inlet pump 1, an outlet pump 2, an intermediate container, a PVT (pressure-volume-temperature) cylinder 6, an oil-gas separator 7, a gas volume flow meter 8, a liquid phase density analyzer 10 and a chromatographic analyzer 9, wherein, one end of the intermediate container is connected with the inlet pump 1, and the other end of the intermediate container is connected with the PVT cylinder 6; the PVT cylinder is connected with the oil-gas separator 7; the separator is connected with the gas volume flow meter 8 and the liquid phase density analyzer 10; the gas volume flow meter and the liquid phase density analyzer are respectively connected with the chromatographic analyzer 9; and the other end of the PVT cylinder is connected with the outlet pump 2. The device has the advantages of reasonable principle and simple structure, and is convenient in operation; and by utilizing the method, the molecular diffusion coefficients of each component in a multi-component injected gas and actual crude oil system in gas phase and oil phase under the conditions of different reservoir temperature and pressure can be determined, thereby providing reasonable basic data for quantitative evaluation of influence of molecular diffusion effect on the enhancement of the recovery ratio by means of gas injection.

The present invention belongs to the field of material synthesis technology, and is especially modified no-adhesive ZSM-5 zeolite catalyst and its preparation process and application in catalyzing the dewatering of dilute alcohol solution to prepare ethylene. The catalyst is prepared with no-adhesive ZSM-5 zeolite as basic material and through one modification process combining high temperature water vapor and acid treatment. The catalyst has high content of effective component ZSM-5 zeolite, high molecule diffusion, high crystallization degree, opened channels and great specific surface area. In catalyzing the dewatering of dilute alcohol solution to prepare ethylene, the catalyst has high catalytic activity, low reaction solution ethanol concentration, low reaction temperature, high ethanol converting rate, high ethylene selectivity and high space velocity.

The present invention is a chemical reactor for catalytic chemical reactions having gas phase reactants. The chemical reactor has reactor microchannels for flow of at least one reactant and at least one product, and a catalyst material wherein the at least one reactant contacts the catalyst material and reacts to form the at least one product. The improvement, according to the present invention is: the catalyst material is on a porous material having a porosity that resists bulk flow therethrough and permits molecular diffusion therein. The porous material further has a length, a width and a thickness, the porous material defining at least a portion of one wall of a bulk flow path through which the at least one reactant passes.

This invention discloses a method for preparing multi-level porous beta-zeolite. The method comprises: soaking monolithic silica gel column in sucrose solution, drying, polymerizing, carbonizing to obtain C-Si composite, wetting the C-Si composite with a mixed solution of Al source, inorganic alkali, organic amine and water, crystallizing, and recovering the product. In this method, carbon material can effectively protect the porous structure of monolithic silica gel column from damage during crystallization process. The obtained beta-zeolite has multi-level pores, including micrometer-scale macropores, mesopores and micropores. The macropores can shorten the diffusion distances of reactive molecules, reduce the pressure decrease of the equipment, raise the unit processing capacity of the equipment, and make the adjustment and control of the product selectivity easier. The mesopores can provide large inner specific surface area, which is meaningful to the catalytic reaction of macromolecules.

The invention relates to a high fused mass strength polypropylene contained long-chain branch and the preparation method thereof. The high fused mass strength polypropylene resin is prepared by polypropylene grafted object, amine or alcohols compound as well as antioxidant and heat stabilizer, etc. The invention adopts a melting and continuously extrusion method with a reaction-type double screw extruder to prepare the high fused mass strength polypropylene, and uses supercritical carbon dioxide to assist the extrusion, which can lower the extrusion temperature, reduce the degradation of polymer and meanwhile greatly strengthen the pervasion of molecule, so as to further promote the reaction. In the reaction process, as chain extender, amine and alcohols compound react with special functional group of polypropylene grafted object, link linearity polypropylene molecular chain, consequently produce novel polypropylene that each grafted point includes two long-chain branch structures and of which the melt flow rate is adjustable. The novel polypropylene is characterized by non-gelatin and strain hardening. The product shows great advantages over a plurality of aspects like color, mechanical property and workability, therefore, the product is suitable for application areas of blowing, thermo-forming, blown film, extrusion and coating, etc.

In the diffusion spectroscopic imaging, in which intensity of molecular diffusion is imaged with separating chemical substances, with suppressing artifacts resulting from object motion of an object, spatial resolution, spectral band and SNR are maintained, and measurement accuracy is enhanced. A measurement for acquiring diffusion SI data is repeated a plurality of times with changing acquisition timing, phase variation of each measurement result is corrected, and a diffusion SI image is reconstructed from the corrected measurement results. In addition, the phase variation is calculated for every point in the space from the diffusion SI data acquired by each measurement or navigation data obtained by each measurement. The phase correction is independently performed for every point in the space.

The present invention relates to a method of preparing a microporous crystalline molecular sieve Inorganic gel having mesoporous skeleton, comprising following steps: (a) adding a meso-SDA (meso-Structure Directing Agent) into a gel composition of synthesizing molecular sieve, (b) subjecting the mixture obtained in the above step (a) to crystallization by a hydrothermal reaction, a microwave reaction, a dry-gel synthesis, etc., and (c) removing selectively organic materials from the resulted material obtained in the above step (b) by a calcination or a chemical treatment. Molecular sieve having mesoporous skeleton synthesized by the present invention exhibits, as compared with conventional zeolite, a good molecule diffusion ability and a greatly improved catalytic activity.

A cap for a container housing a consumer product, in the form of a device that is capable of diffusing a volatile substance inside the container. The device includes a cap liner element for carrying the volatile substance and a barrier element, which is lodged between the cap liner element and the interior of the container. The barrier element is formed of a membrane that is permeable to the vapors of the volatile substance but impermeable to the consumer product, so as to enable molecular diffusion of the volatile substance's vapors into the headspace above the consumer product when the container is closed.

The invention relates to hierarchical zeolite, preparation and application thereof, and belongs to the technical field of catalyst preparation and application. A hierarchical zeolite molecular sieve is synthesized under a microwave assisted heating condition by utilizing organosilane or a mixture of organosilane and surfactant as a template. Compared with traditional hydrothermal synthesis, microwave hydrothermal synthesis has the advantages of high efficiency, quickness, environment friendliness, simple process, low cost and the like. The synthesized material combines the advantages of nano-porous zeolite and a mesoporous material, realizes combination of nano-pores and mesopores, maintains strong acidity, high selectivity and high hydrothermal stability of the nano-porous zeolite, and has the advantage that the large pore diameter of the mesoporous material facilitates molecular diffusion. The material has wide application prospects in petrochemical industry, coal chemical industry and fine chemical engineering.

The present invention is a chemical reactor and method for catalytic chemical reactions having gas phase reactants. The chemical reactor has reactor microchannels for flow of at least one reactant and at least one product, and a catalyst material wherein the at least one reactant contacts the catalyst material and reacts to form the at least one product. The improvement, according to the present invention is: the catalyst material is on a porous material having a porosity that resists bulk flow therethrough and permits molecular diffusion therein. The porous material further has a length, a width and a thickness, the porous material defining at least a portion of one wall of a bulk flow path through which the at least one reactant passes.

The invention relates to a device and method for determining a molecular diffusion coefficient of a multi-component gas-liquid system in a rock core. The device mainly comprises an inlet pump, a confining pressure pump, a pressure returning pump, an intermediate container, a rock core clamper, an oil-gas two-phase separator, a pressure sensor and a computer, wherein one end of the intermediate container is connected with the inlet pump; thee other end of the intermediate container is connected with the rock core clamper; the rock core clamper is connected with the pressure return pump, the confining pressure pump and the oil-gas two-phase separator; and two ends of the rock core clamper are connected with the pressure sensor and the computer. The method comprises the following steps of: transferring an oil sample and a gas sample into the rock core through the inlet pump; contacting an oil phase with a gas phase to generate diffusion and cause the reduction of the gas phase pressure; monitoring the pressure change of a gas phase zone; after the gas and liquid reach the balance, enabling the drained fluid in the rock core to enter the oil-gas two-phase separator; and analyzing and testing the gas phase composition and the property change. The device and method disclosed by the invention are reliable in principle and simple and convenient in operation; and the molecular diffusion coefficient of each component of the multi-component gas-liquid system in real rock core in the gas phase and oil phase can be determined under different temperature and pressure conditions of an oil reservoir and reasonable base data is provided for quantitatively evaluating the influence on the improvement on the recovery ratio caused by a molecular diffusion effect.

The invention provides an H-ZSM-5 zeolite catalyst for preparing propylene from methanol and an application thereof. An H-ZSM-5 zeolite with small crystal grains obtained by directional preparation through the hydrothermal synthesis technology has small crystal grain size and high specific surface area, and can achieve the purpose of shortening the length of a diffusion path of molecules of a product, improving the diffusion performance of the catalyst and reducing the secondary reaction of a low-carbon olefin product. The H-ZSM-5 zeolite catalyst is used in the reaction for preparing the propylene from the methanol, the yield of the propylene and the P / E (propylene / ethylene) weight ratio are greatly improved, and the P / E weight ratio is above 8.

The invention discloses general apparatus and methods for electrochemical energy conversion and storage via a membraneless laminar flow battery. In a preferred embodiment, the battery includes a flow-through porous anode for receiving a fuel and a porous electrolyte channel for transporting an electrolyte adjacent to the porous anode; a flow-through porous cathode is provided for transporting an oxidant; and a porous dispersion blocker is disposed between the electrolyte channel and the porous cathode, which inhibits convective mixing while allowing molecular diffusion and mean flow. Pore structure properties are selected for tuning convective dispersion, conductivity or other macroscopic properties. Specific materials, reactants, fabrication methods, and operation methods are disclosed to achieve stable charge / discharge cycles and to optimize power density and energy density.

The present invention relates to microporous molecular sieve materials and their analogue molecular sieve materials having a crystalline unilamellar or multilamellar framework with a single unit cell thickness in which layers are aligned regularly or randomly, the molecular sieve materials being synthesized by adding an organic surfactant to the synthesis composition of zeolite. In addition, the present invention relates to micro-mesoporous molecular sieve materials activated or functionalized by dealumination, ion exchange or other post treatments, and the use thereof as catalyst. These novel materials have dramatically increased external surface area by virtue of their framework with nano-scale thickness, and thus exhibit improved molecular diffusion, and thus have much higher activities as catalyst and ion exchange resin than conventional zeolites. In particular, the materials of the present invention exhibit high reactivity and dramatically increased catalyst life in various organic reactions such as carbon-carbon coupling, alkylation, acylation, etc. of organic molecules.

The invention discloses a SSZ-13 molecular sieve having micropore-mesopore multi-level pore channel structure, a synthesis method and applications thereof. The synthesis method selects a long-chain double quaternary ammonium salt surfactant as a crystallization synthesis aid, and specially comprises: gelation and aging, crystallization, washing, template agent removing and activating, ion exchange and activation, and other steps so as to obtain the micropore-mesopore ordered-distribution high-crystallinity multi-level pore SSZ-13 molecular sieve. According to the present invention, the obtained molecular sieve has two sizes such as the mesopore pore size distribution of 2-5 nm and the mesopore pore size distribution of 5-15 nm, wherein the micro-pore volume is more than 0.20 cm<3> / g, the mesopore volume is more than 0.35 cm<3> / g, the specific surface area is more than 400 m<2> / g, and the yield of the crystallized product can achieve more than 85%; and the SSZ-13 molecular sieve has the advantages of the micropore zeolite, the macromolecule diffusion and the other advantages of the mesopore middle-macromolecules, and has wide application prospects in the fields of MTO reactions, tail gas catalytic reduction (SCR) reactions, and the like.

The invention relates to a preparation method of an H-ZSM-5 molecular sieve based catalyst and a prepared catalyst; preheating is performed before sealed hydrothermal crystallization through hydro-thermal synthesis technology, which reduces the water content of a gel mixture, increases the solid content of the system, thus reaches the target of producing small crystal grains, and greatly improves the yield per single kettle of the molecular sieve; meanwhile the product separation process is avoided, which reduces the discharge of amine-containing waste water, and reduces environment pollution. With the catalyst of the present invention, the length of the product molecular diffusion path is shortened; the diffusion performance of the catalyst is improved; the secondary reaction of low carbon olefins is reduced; thus the propylene selectivity and P / E ratio are increased; and substances above C4 are ensured to be mainly olefins, and especially to be olefins with poor side chains.

The invention discloses a hydro-dewaxing catalyst and a preparation method and application thereof. The hydro-dewaxing catalyst comprises a carrier modified by a metal aid and silicon, and is prepared by the following steps of: supporting the metal aid by using a conventional carrier impregnation method, modifying by using silicon oil, and forming a silica coating on the surface of the carrier. The method can effectively regulate the acidity and pore shapes of the inner surface and the outer surface of a molecular sieve to contribute to diffusing wax molecules into the pores of the molecular sieve for shape-selective cracking reaction, and ensures higher catalytic activity and higher selectivity for target products; in addition, the acidity of the outer surface of the molecular sieve is lower, the cracking capacity is low, and the side reaction of the target products is reduced. The hydro-dewaxing catalyst is suitable for the hydro-dewaxing process for wax-containing raw materials, particularly the diesel hydro-dewaxing or lubricating oil hydro-dewaxing process.

The invention discloses a hydrodewaxing catalyst, a preparation method and application thereof. The hydrodewaxing catalyst employs a carrier modified by metal auxiliary agent and silicon. First, a carrier is loaded with metal auxiliary agent by an immersion method; then the carrier is modified by silicone oil to form a silicon oxide coating thereon. The method can effectively adjust acidity of an interior surface and an outside surface of a molecular sieve and the pore shape, so as to facilitate wax molecules to diffuse into tunnels of the molecular sieve and carry out a shape selective cracking reaction and an isomerization reaction; the method has high catalytic activity and selectivity on object product; and as weak acidity of the outside surface and low cracking capability of the molecular sieve, side reactions of the object product are reduced. The hydrodewaxing catalyst is suitable for a hydrodewaxing process of a wax-containing raw material, especially a hydrodewaxing process of diesel oil or lubricating oil.

The invention relates to a catalyst for preparing propylene through dehydrogenation of propane and a preparation method of the catalyst. The preparation method comprises the steps: preparing a NaZSM-5molecular sieve with a conventional microporous structure, then placing the obtained NaZSM-5 molecular sieve in a mixed solution of an alkali solution with a templating agent, performing microwave hydrothermal crystallization, performing exchange with an appropriate amount of inorganic acid or an ammonium salt solution, conducting calcination so as to obtain an HZSM-5 molecular sieve with a microporous-mesoporous multi-stage pore structure, and then loading active components and auxiliary agents on the multi-stage pore HZSM-5 molecular sieve so as to obtain the catalyst. When the preparationmethod is compared with the prior art, a mesoporous structure is introduced in the microporous structure of the ZSM-5 molecular sieve, so that the problem of difficult molecular diffusion is solved, the occurrence of carbon deposition is reduced, and the service life of the catalyst is prolonged; meanwhile, through secondary microwave crystallization, reduction of the crystallization temperature and shortening of the time of the entire synthesis process are achieved, and re-migrating of the removed non-framework species to the skeleton is achieved, so that the crystallinity of the ZSM-5 molecular sieve is improved; when the catalyst is applied to a preparation reaction of propylene through dehydrogenation of propane, a high conversion rate of propane and high selectivity to propylene are obtained.