101 results about "Nuclear pore" patented technology

The invention provides a lithium battery diaphragm for power vehicles. The diaphragm has four layers, the layers are respectively from bottom to top a base diaphragm, a nanometer flame retarding layer, an electrospun nanofiber layer and a thermal closed layer, wherein the base diaphragm is a PET nuclear pore membrane with a thickness of 5 microns-20 microns, the nano meter flame retardant layer is a flame retardant ceramic slurry with a thickness of 0.5 micron-10 microns, the thickness of the electrospun nano-fiber layer is 2 microns-5 microns, and the heat closed layer is a heat-resistant epoxy resin with a thickness of 5 microns-10 microns. The invention also provides a preparation method of the lithium battery diaphragm; the heat-resistance and shrinkage performance of the prepared lithium battery diaphragm can be greatly improved, the thermal stability and thermal closed property are significantly improved, and the security is very good.

The invention discloses a composite nuclear track membrane and a preparation method thereof. The composite nuclear track membrane comprises a polyester nuclear track membrane or a polycarbonate nuclear track membrane, wherein a porous cellulose acetate membrane is composited on one surface of the polyester nuclear track membrane or the polycarbonate nuclear track membrane so as to form the composite nuclear track membrane of which the thickness is 67-160 microns, the aperture of the polyester nuclear track membrane or the polycarbonate nuclear track membrane is 1-10 microns, the pore density of the polyester nuclear track membrane or the polycarbonate nuclear track membrane is 2*10<5> / cm<2>-2*10<7> / cm<2>, and the thickness of the polyester nuclear track membrane or the polycarbonate nuclear track membrane is 7-25 microns. The composite nuclear track membrane has the advantage that the surface hydrophilicity is good, the mechanical strength is high, the membrane thickness is moderate, the automatic operation can be realized easily, the flux of the filtering liquid is high, and the assimilative capacity is strong; the composite membrane is an integer, is not layered and is suitable for fabricating roll type filter cores; the porous cellulose acetate membrane composited on the nuclear track membrane is taken as a pre-filtering layer or a support layer of the nuclear track membrane, so that the problems about mechanical strength and thickness of the membrane are solved, and meanwhile, the a pre-filtering problem of the membrane is solved.

The invention discloses a small-bore nuclear pore filter membrane and a production method thereof, which are used for solving the problem that the conventional production process cannot produce a columnar nuclear pore filter membrane with the pore diameter between phi0.03 and phi2 microns. The method comprises the following steps: irradiating a membrane to form a columnar damage area by using high-energy sulfur ions; irradiating the ion-irradiated membrane by using ultraviolet for 1 to 2 hours under an oxygen-containing environment that the oxygen concentration is not lower than 2 / 5; ageing the ultraviolet-irradiated membrane under a ventilated environment; and putting the aged membrane into an alkali etching bath with an ultrasonic device to perform etching, oscillating the alkali etching solution by using ultrasonic during etching, and obtaining the columnar nuclear pore filter membrane with the pore diameter between phi0.03 and phi2 microns after etching. The method is simple, has low cost, can be greatly popularized and can realize industrialization.

The invention relates to a novel nuclear pore membrane (or nuclear track membrane), generally the nuclear track always has conicity after etching, the millipore of the nuclear pore membrane is single-cone or double-cone, the center aperture of the millipore of the double cone is less than the aperture on both surfaces of the membrane. Particles are blocked in the millipore easily when filtering, and the membrane is blocked easily. Meanwhile, the ions with lower mass number are utilized for irradiating the electrolyte membranes, for the nuclear track etching sensitivity is lower, conicity is larger, the nuclear pore membrane with small aperture is made hard. The center aperture of the millipore of the nuclear pore membrane made by the invention is larger than the diameters of both surfaces of the membrane or is of column form capillary tube shape. The shape of the millipore causes the particles larger than the membrane surface aperture to be trapped on the membrane surface, and the nuclear pore membrane is not blocked easily. Meanwhile, a new method is provided for making nuclear pore membranes by utilizing the ions with lower mass number.

The invention relates to an air monitoring and classified sampling method and a device. Through air suction, air with a certain flow velocity passes by nuclear pore filter membranes which have three levels of different apertures of 10mum, 2.5mum and less than 0.3mum, so particles in the air are accurately trapped on the nuclear pore filter membranes in a classification way according to the sizes of the particles. The device which realizes the method comprises an air suction device, a flow controller and a nuclear pore membrane filter. The device can accurately trap the particles which have different diameters in the classification way through the nuclear pore filter membranes which have three levels of different absolute apertures, the particles are all trapped on the surfaces of the nuclear pore filter membranes and can be effectively eluted, so the further accurate composition and content analysis is benefited, and the effectiveness of a monitoring result is improved; and the nuclear pore membrane filter is a detachable disposable filter which is low in price, simple to operate and convenient to use.

The invention discloses a measurement method of the matching between microspheres and pore throats of an oil reservoir. The measurement method comprises the following steps: preparing microsphere dispersion systems with a preset mass concentration; arranging a nuclear pore membrane on a filtering-membrane supporting plate which is arranged at the lower part of a container; taking out the microsphere dispersion system with a first preset volume in the container from the prepared microsphere dispersion systems; controlling the pressure in the container to be the preset pressure, standing for 0.5-4 minutes, switching on a valve arranged at the lower end of the container, acquiring a time parameter when the microsphere dispersion system with a second preset volume flows out of the microsphere dispersion systems, and according to the time parameter, acquiring a blocking parameter of the microsphere dispersion system. The measurement method disclosed by the invention has the advantages that the matching between the microspheres and the pore throats of the oil reservoir can be accurately measured, high-efficiency spreading control is further realized and the utilization efficiency of injected water is improved.

The invention relates to the field of precise separation, in particular to a composite pore nuclear pore filter membrane and a preparation method thereof. A filter membrane base material is selected from a polyethylene terephthalate (PET) or polycarbonate (PC) polyester film, and the thickness is between 20 and 30 micrometers; and a nuclear pore is a compost pore formed by sleeving a plurality ofmicropores in a macropore, the pore diameter phi of the macropore ranges from 8 to 12 micrometers, and the pore diameter phi of each micropore ranges from 1 to 5 micrometers. The method for preparingthe nuclear pore filter membrane comprises the following steps of: irradiating two sides of the polyester film by using two high-energy ions with different kinds of quality and energy, coating a layer of thin oil film on one side of the polyester film, performing ultrasonic oscillation, and etching the film in an alkaline mode. The nuclear pore filter membrane has the characteristics of high flowspeed, large flux, high dirt storage capacity, difficulty of stoppage and low preparation cost; and when used, the composite pore nuclear pore filter membrane is not needed to be matched with a fibrous membrane, and the problem of limited application of the nuclear pore filter membrane due to susceptible dropping of fibers, high adsorptivity, poor high-temperature resistance and the like in the fibrous membrane is solved, so that the nuclear pore filter membrane serving as a high-performance separation material can be widely applied.

The invention relates to a preparation method of a nuclear pore filter membrane and particularly relates to a nuclear pore filter membrane with a pore passage structure combined by a cone-shaped pore passage and a columnar pore passage. A preparation method of the nuclear pore filter membrane with tthe compound pore passage structure mainly comprises the following steps: radiating a polymer film by virtue of high-energy heavy ions, so as to form a latent trace; respectively etching the same surface of the radiated polymer film by virtue of two etching solutions with different track etching speeds, so as to form the novel cone / column compound pore passage structure. The cone / column compound pore passage structure has the obvious structural characteristics that the pore passage is formed by the linkage of an upper part and a lower part, and specifically comprises the cone-shaped pore passage and the columnar pore passage; the columnar pore passage is etched and machined by virtue of liquid with high track etching speed; the cone-shaped pore passage is etched and machined by virtue of liquid with the lower track etching speed. By utilizing the novel pore passage design, the technical problem of low filtration flux of the small-aperture nuclear pore filter membrane can be beneficially solved, and the technical problems of single-layer filtration and repeated cleaning are further beneficially solved.

The invention relates to the medical clinic transfusion field, more particularly, relating to the nuclear track microporous membrane used on a precision medical solution filter and the preparation method. The substrate membrane of the nuclear track microporous membrane used on the precision medical solution filter selects the polycarbonate as the material, and the nuclear track microporous membrane is obtained by high energy charged particle radiation and then sensitized and etching treatment to the substrate membrane, the apertures of the nuclear track microporous membrane are between zero point two micron and ten microns, the density of the nucleopores is that the membrane has five multiply one hundred and five to seven multiply one hundred and five pores per square centimeter. The preparation method of the nuclear track microporous membrane of the invention includes steps of radiation, sensitized treatment, etching and rinsing. The arrangement and application of the precision filter made by the nuclear track microporous membrane of the invention on the terminal of the infusion set of the disposable precision filtering infusion set can effectively filter the insoluble particles in the medical solution, and the filtration rate is more than or equal to ninety five percent, and hold the last pass of the medical solution form entering the human body, thus truly blocking the invasion of the insoluble particles to patients.

The invention relates to a preparation method for a nuclear pore filtering film and particularly relates to the nuclear pore filtering film with an hourglass type pore channel shape. The invention provides an hourglass type pore channel nuclear pore filtering film and a preparation method thereof. The preparation method comprises the following steps: radiating a PET (Polyethylene Terephthalate) or PC (Polycarbonate) thin film by heavy ions provided by a high-energy accelerator to form a latent trace; selecting a NaOH etching solution and carrying out pre-etching on a radiated polymer thin film; putting the film into a constant-temperature box with a certain temperature and annealed; finally, etching by using a NaOH solution. The hourglass type pore channel nuclear pore filtering film comprises a nuclear pore which is formed on the polymer thin film by radiating and etching through the heavy ions; the section of a pore channel of the nuclear pore is similar to an hourglass shape. The polymer thin film is the PET / PC thin film; the thickness is 10-30 microns; the range of the pore diameter of an outer pore is 2-10 microns and the range of the pore diameter of an inner pore is 0.2-3 microns. Compared with columnar and tapered pore shapes, an hourglass type pore channel can improve the filtering speed except the previous filtering precision is kept; meanwhile, the dirt containing capability of the nuclear pore filtering film is improved and the nuclear pore filtering film is not easy to block, so that the filtering performance of the nuclear pore filtering film is improved.

The invention discloses a filter mask for harmful particulate pollutants. The filter mask comprises a gas filter unit, a surface cup and a mask shield, and one end of the surface cup is hermetically docked with one end of the mask shield; the gas filter unit comprises a filter barrel, a filter membrane and a sterilization unit arranged in the filter barrel; the filter membrane is arranged at one end of the filter barrel; the filter membrane comprises a hydrophilic spinning bonded nonwoven fabric layer, a first melt-blowing nonwoven fabric layer, a wood pulp layer, a nuclear pore membrane filtration layer and a water-repellent spinning bonded nonwoven fabric layer which are laminated and composited in sequence from the position close to the inner side of the mask shield to the outer side of the mask shield; the sterilization unit comprises a gas inlet distribution disc, a capillary gas-guide tube, a gas outlet collection disc and an ultraviolet lamp; two ends of the capillary gas-guide tube are communicated with the gas inlet distribution disc and the gas outlet collection disc, and the capillary gas-guide tube is arranged in a spiral winding manner between the gas inlet distribution disc and the gas outlet collection disc; the ultraviolet lamp is used for performing ultraviolet irradiation on the capillary gas-guide tube. The filter mask has the advantages of use comfort, good user experience, thorough sterilization and safety in use.

The invention discloses a technique for producing nucleopore membranes by a miniature particle accelerator, belonging to the technical field of nuclear. If the nucleopore membranes are produced by a reactor, mass number and energy dispensability of uranium fission fragment are large, pore sizes of the nucleopore membranes are not uniform, and even blind holes are produced. If a heavy ion accelerator is used for accelerating ion irradiated dielectric membrane of which the mass number is equal to that of the uranium fission fragment, the mass number and the energy are unique, the directivity is good, and the thickness for penetrating through the membranes is large. But the particle accelerator is expensive, and high in running cost. Only few such kind of particle accelerators exist internationally, and the production of the nucleopore membranes is restrained. If the nucleopore membranes are produced by the miniature particle accelerator, the ions are single in form, the energy dispensability is small, and beam directivity is good; and the miniature accelerator is low in production cost and low in running cost. The invention mainly describes the technique for producing the nucleopore membranes by the miniature particle accelerator.

A folded filter element structure, a filter cartridge device and a processing method thereof, the folded filter element structure includes a filter element frame, the filter element frame is connected with a ring-shaped folded filter element, the lower end of the filter element frame is provided with a lower cover; the filter cartridge device includes a filter cartridge and a The pleated filter element structure; during processing, one or more materials in the nuclear pore fine filter membrane, non-woven fabric, and nuclear pore coarse filter membrane are compositely welded together, and folded or not folded in half along the width direction and placed in parallel, and then along the The stretching direction is folded into a louver shape, and its two ends are sealed and welded to form a ring-shaped folded filter element; the folded filter element is placed on the filter element frame, and then the upper and lower edges of the folded filter element are welded to the upper and lower covers to form a sealed body; put the sealed body Insert it into the frame of the filter cartridge so that the upper and lower covers fit closely with the inner wall of the frame of the filter cartridge. The filter element of the present invention is self-contained, easy to replace, low in production cost, long in service life, has increased effective filtering area of ​​the filter element, strong dirt holding capacity, improved filtering efficiency, reduced replacement frequency, more convenient use and wide application range.

The invention relates to an antibacterial type PM2.5 (Particulate Matter2.5) filter material and application thereof. The antibacterial type PM2.5 filter material is mainly characterized by sequentially consisting of a windward layer, a primary filter layer, a sterilization layer, an active carbon filter layer and a fine filter layer, wherein the primary filter layer and the fine filter layer are nuclear pore films. The sterilization layer is provided with nano sliver particles; and the purpose of blocking PM 2.5 particles is effectively realized by utilizing the characteristics of uniform film hole diameter, uniform hole density and high porosity of the nuclear pore films and additionally arranging the sterilization layer through multi-layer filtration and adsorption effect; a filter element and a respirator, which are manufactured by the filter material, block the PM 2.5 particles more effectively in comparison with a conventional respirator, are long in service live, are good in gas permeability, meet characteristics of environmental-friendly requirements, and are worthy of being produced and popularized.

The invention relates to a lithium battery diaphragm and a preparation method thereof. The lithium battery diaphragm has a multilayer structure, an organic polymer nuclear pore membrane serves as a base membrane, modified graphene oxide membranes are compounded on two sides of the base membrane, and a closed layer membrane is compounded on the outer layer of the graphene oxide membrane; the organic polymer nuclear pore membrane adopts a polyester (PET) nuclear pore membrane, a high density polyethylene nuclear pore membrane or an ultra-high molecular weight polyethylene nuclear pore membrane. The battery diaphragm disclosed by the invention has uniform pore structure and pore distribution as well as high porosity; due to the addition of the modified graphene oxide material, the hydrophilic performance of the membrane layer is improved, the environment adaptability of the diaphragm is improved, the resistance is reduced, and the battery efficiency is improved. Moreover, using metallic materials is avoided, and environmental hazards caused by the electrolyte membrane are reduced.

The invention discloses a method for preparing nano zinc oxide wires by using solid nuclear track technology. In the method, through nuclear pore film with a pore diameter of 100 to 600 nanometer is used as a template, a 110-to-200-nanometer-thick gold layer is plated on one side of the nuclear pore film, and a 10-to-40-micrometer-thick copper layer is deposited on the gold layer electrochemically; then a platinum wire is used as an anode and a gold, copper substrate is used as a cathode, zinc oxide is electrochemically deposited to form zinc oxide nanowires, wherein electrolyte is mixed solution of 0.05 to 0.2mol / L KCl, 2 to 7mmol / L ZnCl2 and 3 to 8 mmol / L H2O2, the pH value is 6.5 to 7.5, the electrolysis voltage is 0.8 to 1.5V, and the electrochemical deposition time is 1 to 5 hours. The diameter of the produced zinc oxide nanowires is 100 to 600 nanometers, and the length is 5 to 8 micrometers.

The invention discloses an efficient haze filtering nuclear pore membrane filter and an efficient haze filtering nuclear pore membrane respirator. The filter comprises a nuclear pore filter membrane and a support mesh, wherein the nuclear pore filter membrane and the support mesh are stacked and connected together; the efficient haze filtering nuclear pore membrane respirator comprises a respirator body; the respirator body comprises an inner layer body and an outer layer body which are permeable; the edges of the inner layer body and the outer layer body are connected, so that an interlayer is formed between the inner layer body and the outer layer body; openings are formed in the edges of the inner layer body and the outer layer body; at least one efficient haze filtering nuclear pore membrane filter is arranged in the interlayer through the openings. The efficient haze filtering nuclear pore membrane filter and the efficient haze filtering nuclear pore membrane respirator are simple in structure and convenient to use; a good effect of effectively filtering thin particle matters of PM (Particle Matter) 2.5.

The invention discloses a method for preparing a nuclear pore enzyme membrane of a sucrose biosensor by using beta-galactosidase, aiming at providing a method for obtaining the nuclear pore enzyme membrane of the sucrose biosensor only by immobilizing two enzymes. The method comprises the steps: beta-cyclodextrin is weighed and taken to be dissolved in the mixed solution formed by low concentration NaOH and glutaric dialdehyde; after that, the mixture is heated and treated at the temperature of 60 DEG C until the crystalloid is dispersed, and poly beta-cyclodextrin having active aldehyde group is formed by cross linking reaction; then, the poly beta-cyclodextrin having the active aldehyde group is washed by distilled water until the NaOH on the surface of the poly beta-cyclodextrin is thoroughly removed; after being dried at the room temperature, the poly beta-cyclodextrin is milled into granules basically having uniform size; the poly beta-cyclodextrin granules having the active aldehyde group are taken as fixing material and then is fully mixed with mixed enzyme solution to have reaction for 80 minutes at 25 DEG C to cause the enzyme immobilization; the immobilized enzyme is evenly coated on the surfaces of two nuclear pore membranes to be made into the nuclear pore enzyme membrane of the sucrose biosensor having a sandwich structure.

The invention discloses a preparation method of an implanted magnetic control drug microchip, which has the steps of: firstly, preparing a polylactic acid drug chip with a drug storage pool by a polydimethylsiloxane convex plate, adding drugs into the drug storage pool and covering ferroferric oxide nanometer particles with high purity on the drugs, and finally, sealing the drug storage pool by a nuclear pore polycarbonate membrane. The preparation method has the advantages of simple operation, easy implementation and low cost. After the obtained polylactic acid chip with drugs is implanted in a human body, the active control of the release action of the drugs can be really realized by the magnetic property of ferroferric oxide and the release of the drugs in fixed point, time and ration of the added drugs through pulse. The invention has wide application prospect in organizational project and the field of the slow release of drugs.

The invention discloses a nuclear track membrane and electrostatic spinning composite membrane and a preparation method and application thereof. The composite membrane is composed of an electrostaticspinning layer, a nuclear track membrane and a base material from top to bottom. The composite membrane is high in rejection rate, good in air permeability and easy to clean; the composite membrane can be applied to the aspects such as liquid filtering and air filtering, and comprises the filter membrane industry fields of waste water treatment, oil-water separation, food and medicine, biochemicalengineering and the like.

The invention relates to a nuclear pore film automatic production device adaptive to a beam flow, and a method. The nuclear pore film automatic production device is characterized in that the device comprises a beam flow device, a data detection system, a control device and a film rolling machine; the beam flow device is used for emitting the beam flow to irradiate an irradiation film; the data detection system is used for real-timely detecting and collecting the size and position of the beam flow emitted by the beam flow device; and the control device is used for obtaining data of the data detection system, processing the data and then sending an instruction to the film rolling machine, so that the rotating speed of the film rolling machine is matched with the size of the beam flow, and itis ensured that nuclear hole film production is always in an expected state.

To provide a new technique by which efficient transfection is ensured in delivering a target gene into a cell, disclosed is a nucleic acid construct for nuclear import, which comprises a ternary complex consisting of a nucleic acid substance containing a gene to be delivered into the nucleus of a cell, an importin protein (for example, importin-β) capable of passing through the nuclear pore and involved in the nuclear transport, and a binding substance (for example, polyethyleneimine) bound to both of the nucleic acid substance and the importin protein. Nucleic acid transport from outside of a cell into the cell nucleus can be particularly promoted by administering the nucleic acid construct bound to a cell membrane receptor binding factor and / or a membrane fusing substance, or administering the nucleic acid construct encapsulated in a non-viral vector (for example, Sendai virus envelope) having cell membrane permeability and membrane fusing properties.

The present invention relates to a nuclear pore membrane small sample etching apparatus, which is mainly characterized by comprising an etching cup, wherein a sealed upper cup cover is arranged above the etching cup, an inner cover performing secondary sealing on the etching cup is arranged below the upper cup cover, a membrane bracket is arranged below the inner cover, a thermal-sensitive probe is arranged inside the etching cup, the etching cup has the double-layer hollow cup wall, the upper side and the lower side are respectively provided with a water inlet and a water outlet, the water inlet and the water outlet are respectively communicated with the water outlet end and the water inlet end of a constant temperature circulation system, and magnetic transmission stirring comprising a magneton and a magnetic stirring device is arranged below the etching cup. According to the present invention, with the magnetic stirring, the etching liquid maintains the uniform state; with the circulating water heating of the etching cup interlayer, the etching liquid temperature is uniform; the built-in thermal-sensitive probe and the etching liquid are connected, such that the etching liquid temperature can be accurately controlled; the whole etching cup maintains the sealed state, such that the solution evaporation can be reduced; and the sample is fixed through the sample clamp, such that the sample maintains the flat state, the sample taking is convenient, and the cleaning and air-drying are easy.

The invention discloses a circulating filtration type nuclear pore membrane etching device. The device is used for nuclear pore membrane batch etching machining and mainly applied to the fields of nuclear pore membrane product machining, nuclear pore membrane preparation and the like. The circulating filtration type nuclear pore membrane etching device is mainly characterized in that an etching groove is connected with an input port of a heating groove through a pipeline, and the pipeline is provided with a water path switch; output of the heating groove is connected with the etching groove through a circulating filtration machine, heaters are arranged in the heating groove, and a thermosensitive probe for monitoring the temperature of etching liquid for the heaters is arranged in the etching groove; a stirrer is arranged in a liquid blending groove, and the liquid blending groove is connected with the etching groove through a water path switch and a liquid addition filtration machine via a pipeline; a concentration probe for monitoring concentration in the heating groove is arranged in a liquid supply groove, and the liquid supplement groove supplies etching liquid to the etching groove automatically. The device has the advantages of automatic temperature and concentration compensation, circulating flow, self-cleaning performance and the like, and can perform nuclear pore membrane batch etching efficiently for a long time.

The invention relates to a tracing and counting method for detecting quantity of exogenous microorganisms in soil. The tracing and counting method comprises the following steps: 1) preparing dye stock solution and working solution; 2) activating and culturing bacteria, centrifuging to obtain target bacteria, fixing cells, adding dye working solution, and dyeing in the dark place, so that dyed bacteria are prepared; 3) adding the dyed bacteria into soil to be cultured, collecting a soil sample after culture, carrying out oscillating extraction to obtain the target bacteria, diluting, then filtering with a black nuclear pore filter membrane, then placing on a glass slide, and sealing the glass slide; and 4) observing and counting under ultraviolet light by adopting a fluorescent microscope, and converting the quantity obtained by counting into the quantity of microorganism cells contained in per kg of dry soil. The tracing and counting method provided by the invention has the advantages that a fluorescent dyeing counting technology is combined with a fluorescent labelling technology, and growth and propagation conditions of the exogenous microorganisms added into the soil are traced and quantified; and the used fluorescent dye is convenient and fast to operate, extremely high in sensitivity, good in stability and extremely low in usage amount, so that a practical and reliable soil exogenous microorganism tracing and counting method is provided.

The invention discloses a polyethylene nuclear pore membrane for a lithium battery and a preparation method. The method comprises the steps of irradiating a polyethylene film by using heavy ions Au orKr generated from an accelerator; carrying out sensitization in ultraviolet light; and immersing a product into a mixed solution, etching, and then soaking, cleaning and drying in a sodium hydroxideaqueous solution at room temperature to obtain the polyethylene nuclear pore membrane for the lithium battery. The method disclosed by the invention is relatively simple, the process is easy to control, the aperture is uniform, the hole density is high, the aperture and the porosity are easy to control, the cost is relatively low and the used reagent is easy to get.

The invention discloses a PET (polyethylene terephthalate) precision infusion filtering nuclear pore membrane hydrophilization treatment process. The process is characterized by including steps of aninitiator bath preparation, initiating treatment, grafting bath preparation, grafting treatment and the like. The process is simple, safe and low in equipment requirement, membrane intrinsic mechanical performances and nuclear pore membrane structures are unchanged after treatment, membrane surface hydrophilicity can be remarkably enhanced, and accordingly air interception capacity, liquid retaining height, liquid flux of membranes can be increased, and low toxicity and high durability are realized. By adoption of the process, infusion functions of PET precision infusion filtering nuclear poremembranes can be improved, and infusion safety is improved.

The invention relates to the field of medical apparatus and instruments, in particular to a composite membrane used for a filter and a preparation method thereof and aims at providing the composite membrane which is used for the filter and capable of achieving industrial automation and guaranteeing the product quality and the preparation method thereof. The composite membrane is composed of a nuclear track membrane and a lining membrane; the nuclear track membrane and the lining membrane are bonded into a whole through a composite processing method, wherein the nuclear track membrane is made of PET, and the thickness of the nuclear track membrane ranges from 0.01 mm to 0.02 mm; the lining membrane is made of PE or PP, and the thickness of the lining membrane ranges from 0.1 mm to 0.15 mm. The composite membrane has the advantages of being simple in structure, reasonable in design, convenient to use and the like.

The invention discloses a gravity type hemodialysis device, which belongs to the field of medical equipment, and comprises: a blood inlet (1), a filter membrane (2), and a blood outlet (3); the blood inlet (1) is arranged in a cylinder The upper end of the body, the filter membrane (2) is set in the cylinder, and the blood outlet (3) is set in the lower end of the cylinder; the cylinder is made of medical polyvinyl chloride material; the filter membrane is vertically installed in the cylinder In the middle of the body, the space inside the cylinder is divided into two; the filter membrane is composed of three layers of nuclear pore membranes; the medium density of the three layers of nuclear pore membranes is 5 microns, 3 microns, 0.2 microns, three The order of arrangement of nuclear pore membranes from left to right is 5 microns, 3 microns, 0.2 microns.