66results about How to "Membrane performance is stable" patented technology

A process and apparatus is described for filtering water with immersed membranes. In a batch process, permeate is withdrawn while the flow of feed is reduced or stopped at the end of a permeation cycle. The water level is reduced to a level where a portion of the membranes are exposed to air before draining the tank. In this or another process, the level of liquid is reduced to correspond with an area of the membrane fibers having an accumulation of solids. Aeration is provided for a period of time with the liquid at this level to dislodge at least a portion of the solids from the membranes. In these or other processes, the tank is partially drained between cycles to deconcentrate the tank, aeration is provided during backwashing and intermittently while permeating, and/or retentate is withdrawn from the tank during a portion of a permeation step.

The present invention provides a process for producing a concavo-convex pattern film which excels in its peelability from an embossing roll and in coatability of an anti-reflection layer, etc. There is provided a process of producing a concavo-convex pattern film by forming a concavo-convex pattern on the surface of a transparent resin film employing an embossing roll having on the surface a convex-concavo pattern, characterized in that the embossing roll is made of glass and a photocatalyst layer is provided on the surface of the embossing roll, characterized in that the process comprises the steps of introducing a UV curable resin composition between the embossing roll and a transparent resin film provided around the embossing roll to form a UV curable resin layer, exposing the UV curable resin layer to UV rays to form a UV cured resin layer having on the surface a concavo-convex pattern, the UV rays being emitted from the interior of the embossing roll, and peeling the UV cured resin layer together with the transparent resin film from the embossing roll.

A membrane valve wherein the shutter disk is retained in contact with the valve seat during ejection of liquid or gas by means of one or more ribs that are substantially in contact with the shutter disk along one or more lines secant to the shutter disk and/or by means of one or more rows of secondary clamping pins that are engaged in matching openings on the valve seat. Further, a second stage pressure reducer for two-stage underwater regulators incorporating a membrane valve wherein the shutter disk is retained in contact with the valve seat during exhalation of gas by means of one or more ribs that are substantially in contact with the shutter disk along one or more lines secant to the shutter disk and/or by means of one or more rows of secondary clamping pins that are engaged in matching openings on the valve seat.

CO₂-facilitated transport membrane that can be applied to a CO₂-permeable membrane reactor is stably provided. The CO₂-facilitated transport membrane is provided such that a gel layer 1 composed of a hydrogel membrane is deposited onto a porous membrane 2. More preferably, the gel layer 1 deposited onto a hydrophilic porous membrane 2 is coated with and supported by hydrophobic porous membranes 3 and 4. The gel layer contains a deprotonating agent including an alkali metal element together with glycine. The deprotonating agent is preferably a carbonate or a hydroxide of an alkali metal element, and more preferably, the alkali metal element is potassium, cesium, or rubidium.

The invention relates to a long-chain unsaturated fatty acid-modified acrylate emulsion and a preparation method thereof. The acrylate emulsion is prepared from raw materials such as acrylate soft monomers, acrylate hard monomers, long-chain unsaturated fatty acid, an initiator, an emulsifier, sodium bicarbonate and water by virtue of emulsion polymerization. The emulsion prepared by the preparation method takes the long-chain unsaturated fatty acid as a functional monomer which is introduced into an acrylate emulsion system and accounts for 0.5%-5% of the total amount of the monomers; the film performance is improved by virtue of further self-crosslinking reaction of unsaturated double bonds of the functional monomer during a film drying process to solve problems of poor water resistance, lower hardness, and the like of an existing acrylate emulsion film, and use of an artificially synthesized modifier which is relatively high in price and causes environmental pollution further can be avoided. By introducing the long-chain unsaturated fatty acid, not only can the film performance be effectively improved, but also the acrylate emulsion can be developed in a green direction to satisfy environmental protection requirements well.

The invention discloses a preparation method and application of a sulfonated polyether-ether-ketone-carboxylated titanium dioxide hybrid membrane. The preparation method comprises the following steps of: preparing sulfonated polyether-ether-ketone and solution of the sulfonated polyether-ether-ketone; preparing carboxylated titanium dioxide sol; mixing the carboxylated titanium dioxide sol and the solution of the sulfonated polyether-ether-ketone to perform condensation polymerization to form membrane casting solution; after standing, filtering and de-foaming the membrane casting solution, curtain coating, drying and annealing the membrane casting solution to form a membrane; and acidizing and drying the membrane to obtain the sulfonated polyether-ether-ketone-carboxylated titanium dioxide hybrid membrane. The hybrid membrane serves as a direct methanol fuel cell proton exchange membrane. The hybrid membrane has the advantages that: the preparation method is simple; nano inorganic titanium dioxide particles are uniformly distributed in the prepared membrane; a carboxyl group effectively improves the performance of the membrane; and the hybrid membrane has relatively low methanol permeability and relatively high proton conductivity.

The invention provides a planographic printing plate precursor that is capable of providing a planographic printing plate in which ablation at the time of infrared laser exposure is inhibited and which has excellent developability of a non-image portion and printing durability of an image portion. The photosensitive planographic printing plate precursor, includes: an image recording layer on a hydrophilic support, the image recording layer including: (A) an infrared absorber; and (B) a copolymer having a repeating unit having a zwitterionic structure in a side chain thereof, and a repeating unit having a heteroalicyclic structure or a repeating unit having a hetero atom and an alicyclic structure in the main chain thereof.

The present invention provides a medical material and a blood purification apparatus each having high anti-thrombotic properties and high safety. The apparatus is produced by incorporating therein a medical material which has a hydrophilic copolymerization polymer present on a surface thereof which is to be in contact with blood, wherein particulate protuberances each having a particle diameter of 50 nm or more are present on the surface which is to be in contact with blood at a density of 3 particles/μm² or less and the relaxation time of adsorbed water in the hydrophilic copolymerization polymer is 2.5×10⁻⁸ seconds or shorter and 5.0×10⁻¹⁰ seconds or longer at −40° C.

The invention provides a fireproof and/or fire-extinguishing microcapsule, a preparation method thereof and an application of the microcapsule. Modified polyisocyanate prepolymers are mixed with fireproof and/or fire-extinguishing materials, mixture is dispersed in water, and polyhydric alcohols and/or polyamines are added into the water to prepare the fireproof and/or fire-extinguishing microcapsule. High molecular polymerization monomers are designed and selected to synthesize the microcapsule with various enhanced physicochemical properties of shell materials, the strength, the flexibilityand the sealing performance of the microcapsule are greatly improved, so that the microcapsule can be directly and independently used as a fire-extinguishing agent, the microcapsule can also be individually used as a main material or functional additive, added into various composite materials and conveniently and directly used for preparing fireproof and/or self-excitation fire-extinguishing materials in various fields of coatings, adhesives, rubber, plastics and the like, and the applicable range and the application field of gas and liquid fire-extinguishing materials and the fireproof and/orfire-extinguishing microcapsule are greatly widened.

The present invention provides a separation membrane having a plurality of concavoconvex parts which have a height difference of from 100 μm to 2000 μm and are formed on at least one surface of the separation membrane, in which an average value d1 of a minimum thickness and an average value d2 of a maximum thickness in the concavoconvex parts satisfy the following relational expression

0.8≦d1/d2≦1.0.  [1]

The invention discloses a nano-sized high-flux PVDF (polyvinylidene fluoride) plate ultrafiltration membrane as well as a screening method and a preparation method thereof, and belongs to the technical field of PVDF plate ultrafiltration membranes. The PVDF plate ultrafiltration membrane with high membrane flux is characterized by being prepared from raw materials in parts by weight as follows: 10-25 parts of PVDF, 70-85 parts of a solvent, 5-15 parts of a pore forming agent and 0.5-5 parts of a nanomaterial. According to the plate ultrafiltration membrane with high-flux PVDF membrane flux as well as the screening method and the preparation method thereof, the membrane formula screen method is optimized scientifically, so that the material ratio is optimized, the consumption quantity accuracy of the materials is improved, and a membrane product with high flux, low cost and long service life is prepared.

The electrochemical performance of an ion-exchange membrane in a fuel cell system may be improved by impregnating therein a perfluoroamine. The amine may be primary, secondary or tertiary. Further, the amine is preferably water insoluble or only slightly water soluble. For example, the amine may be perfluorotriamylamine or perfluorotributylamine. Use of such a membrane system within a fuel cell may allow high or low temperature operation (i.e. at temperatures greater than 100° C. or less than 0° C.) as well as operation at low relative humidity.

The invention discloses a preparation method and application of an amphiphilic chitosan derivative protein adsorption-resistant coating. The preparation method comprises carrying out hydrophobic modification on chitosan through cholesteryl chloroformate to obtain an amphiphilic cholesterol-modified chitosan (CHCS), uniformly spin-coating a glass slide with the CHCS solution, carrying out drying at 20-80 DEG C to obtain a CHCS protein adsorption-resistant coating, characterizing physical and chemical properties of a CHCS film and a CHCS monomolecular film, and researching protein adsorption-resistant performances of a series of CHCS coatings. The research result shows that a substrate coated with the CSCH film has good protein adsorption resistance. The preparation method of the protein adsorption-resistant coating has simple processes and utilizes easily controlled conditions. Chitosan has good biocompatibility, blood compatibility, safety, microbial biodegradability, film-forming performances and a wide resource range, can reduce a production cost and is expected to become a novel environmentally friendly anti-fouling material.

A process for modifying a polymeric photoactive sulfone membrane includes placing the membrane into the presence of acrylic acid monomer dissolved in a solution and without sensitizer or free radical initiator and exposing the membrane to non-ionizing UV radiation for modifying the membrane by chemical grafting of the monomer at the surface of the membrane. The membrane can be polysulfone, polyethersulfone or polyarylsulfone. The radiation is selected to have an energy below that at which chain scission occurs and above that at which maximum grafting occurs. The process includes washing the modified membrane in a washing agent containing ethanol, glycol, ether, acid, hydrocarbon, or mixtures thereof, to wash homopolymer formed in the solution from the modified membrane, but preferably ethanol.

The invention relates to an electric field strengthening assembly method and a device of a polyelectrolyte compound membrane, and belongs to the membrane separation technical field. The prior multi-layer electrostatic adsorption self assembly method is often required to compound 50 to 60 layers to get good membrane performance, the membrane making procedure is complicated, the period is long, and the adjustable and controllable performance of the membrane structure is poor. The electric field strengthening assembly method and the device induct direct current fields on both sides of a supporting body, during the static adsorption or dynamic filtration polyion liquor process, the polyion is combined with a base through the strengthening of the extra electric field force, and a multi-layer membrane assembly is realized and the orderliness and the regularity of the membrane structure are adjusted and controlled. The pervaporation testing of the front and the rear parts of the electric field strengthening assemble compound membrane shows that the separation factor of the compound membrane is improved, and the testing of an atom force microscope shows that the membrane surface tends to be flat under the strengthening effect of the electric field, and the orderliness and the regularity of the compound membrane are improved.

A membrane reactor with divergent-flow channel includes a reaction pipeline, a membrane and a purge (sweep) pipeline sequentially arranged from inside to outside or from outside to inside. The reaction pipeline has a cross-sectional area increment from the front (upstream) end to the rear (downstream) end, so that the flow velocity of a reactant gas is decreased from the upstream end to the downstream end to extend the residence time of the reactant gas and improve the reaction rate of the reactant gas. The sweep pipeline has a cross-sectional area decrement from the upstream end to the downstream end, so that the flow velocity of a purging (sweeping) gas is increased from the upstream end to the downstream end to accelerate the reactant gas, and a product gas generated from the reaction passes through the membrane and enters the sweep pipeline to improve the reaction efficiency.

The invention discloses a disk tube type nanofiltration membrane which comprises a base membrane layer and a modified separation layer arranged on the surface of the base membrane layer, wherein the modified separation layer is prepared from nano oxide, an amphoteric gemini surfactant and polypiperazide; the amphoteric gemini surfactant can carry out surface treatment on the nano oxide to uniformly disperse the nano oxide and achieve a good modification effect; meanwhile, during interface polymerization, migration of the amphoteric gemini surfactant enables the nano oxide to be dispersed on the surface of the membrane more uniformly, so that the use amount of the nano oxide is reduced, and the production cost of a filtration membrane material is reduced. Furthermore, due to improvement onthe dispersivity of the nano oxide and upgrading of the performance of the amphoteric gemini surfactant to the membrane, the obtained nanofiltration membrane is high in filtration performance, can beapplied to a disk tube type system, and is good in filtration effect, high in water flux and high in desalinization rate. The invention further provides a preparation process of the disk tube type nanofiltration membrane. The preparation process is simple in step, mild in condition and suitable for industrial batch production.

The invention aims to provide a T-type molecular sieve/BTESE composite membrane with higher separation performance, high temperature resistance and acid resistance and a preparation method thereof. The preparation method of the T-shaped molecular sieve/BTESE composite membrane comprises the following concrete steps: 1) pretreating a carrier tube; 2) preparing a coarse seed crystal solution of a Tmolecular sieve and a fine seed crystal solution of the T molecular sieve to obtain a carrier tube into which coarse and fine seed crystals are introduced; 3) putting the carrier tube into which the coarse and fine seed crystals are introduced obtained in the step (2) into mother liquor for a crystallization reaction; and 4) preparing a BTESE solution, then dip-coating or wipe-coating the T-shapedmolecular sieve membrane obtained in the step (3) with the BTESE solution, and then carrying out baking to obtain the T-shaped molecular sieve/BTESE composite membrane.

The present invention relates generally to the field of chemical/mechanical polishing of substrates. In particular the invention relates to methods of producing improved membranes for use in chemical/mechanical polishing systems. The present invention provides a method of improving the properties of a flexible membrane for use in chemical/mechanical polishing, the method including subjecting the membrane to elevated temperatures.

The invention relates to a flexible rare earth transparent luminescent film applied to a silicon-based solar cell and a preparation method thereof. The composition of the film comprises a rare earth complex and a polymer matrix material (PMMA); wherein the mass ratio of rare earth complex: PMMA is 1: 40-60; and the rare earth complex is Ln(L1)3(L2)1, Ln is a rare earth element, L1 is a first organic ligand, L2 is a second organic ligand, and L1 and L2 are different; wherein the rare earth element Ln is specifically one or more of Eu, Tb and Yb. The preparation method is simple and rapid, and the flexible rare earth transparent luminescent film is 20-30 or more times larger than the film in the conventional work. The size of the film provides a good foundation for further improving the utilization of sunlight and promoting the large-scale use of the silicon-based solar cell.