63 results about "Dialysis membranes" patented technology

The invention belongs to the field of carbon nanomaterials, and provides a method for preparing a carbon quantum dot material doped with elements such as silicon and aluminum by oxidative depolymerization and stripping of coal gangue. Comprising the steps of screening and matching of coal gangue, oxidative depolymerization stripping, centrifugal dialysis membrane filtration and modification, drying and the like, raw materials and all the steps are specifically set, and the particle size or fluorescence performance of fluorescent carbon dots can be specifically selected and set according to selective oxidative depolymerization stripping conditions. The main particle size of the prepared multi-inorganic-element doped carbon quantum dot material is kept within the range of 1.5-2.0 nm, the structure is stable, the optical performance also meets the requirements, and the material can be further modified and is expected to be applied to the fields of photovoltaic equipment, biological imaging, photocatalytic degradation of organic pollutants or sensing and the like.

The invention discloses an electrophoresis and dialysis integrated device, and designs a multistage dialysis and electrophoresis composite separation device driven by an electric field, a separation pool is designed into a plurality of multistage liquid boxes which are mutually independently communicated, and a positive electrophoresis electrode and a negative electrophoresis electrode are oppositely arranged on the inner sides of the outermost side walls of the two liquid boxes on the outermost side of the separation pool. A driving electric field from one end to the other end of the separation tank is formed after electrification, separated dialysis membranes are arranged on the communicating surfaces of every two liquid boxes, the dialysis membranes among the multi-stage liquid boxes are provided with multi-stage apertures according to requirements, charged particles of sample liquid migrate in the direction of the electric field under the action of the electric field, and when the charged particles pass through the dialysis membranes with different apertures, the charged particles are separated from the sample liquid. Molecules larger than the aperture are blocked, and molecules smaller than the aperture can continue to migrate to a next-stage liquid box, so that rapid molecular cascade separation under the driving of an electric field is realized; compared with existing electrophoresis, gel is not used, dyeing is not needed, and a sample is easy to recover; compared with traditional dialysis, the separation speed is greatly increased.

A process for producing a phenolic monomer product comprising depolymerizing a recycled polymeric material to obtain a depolymerized mixture comprising phenolic monomers and purifying the depolymerized mixture. The polymeric material comprises at least one PAES polymer and at least one additive, and the PAES polymer preferably comprises a backbone comprising at least one sulfone recurring unit, a first end group being a halide, and a second end-capped group, preferably selected from alkoxy groups and / or phenoxy groups. The additive comprises a polyalkylene oxide and / or a polyvinylpyrrolidone (PVP). A purity of at least 95 wt% of phenolic monomers can be achieved in the product. In particular embodiments in which a recycled hemodialysis membrane comprises a polyethersulfone and PVP, a purity of at least 98 wt% based on the total weight of the phenolic monomer product of 4,4'-sulfonyl phenolic monomers can be achieved after depolymerisation and phenolic monomer purification.

The invention belongs to the technical field of medical equipment, and particularly discloses a clinical hemodialysis device and a using method thereof.The clinical hemodialysis device comprises a dialysis box, and a dialysis assembly is arranged on one side of the dialysis box; the dialysis assembly comprises a dialyzer, a liquid inlet pipe, a liquid outlet pipe, a dialysate inlet, a dialysate outlet, a dialysis membrane, an inner partition plate and an adjusting structure. By means of the flow guiding structure, flow guiding can be conducted when blood enters the dialysis cavity, the situation that blood easily flows in a deviated mode after entering the dialysis cavity, so that no blood passes through the surface of a dialysis membrane on one side, the blood and dialysis efficiency is affected is prevented, the treatment duration is shortened, complications are reduced, and the treatment effect is improved by heating the blood. Therefore, the blood is kept at the temperature acceptable by the human body, the comfort of a patient during treatment is improved, and the dialysis treatment is safely and efficiently carried out.

This invention discloses a testing fixture for the water contact angle of hollow fiber membranes, including a support assembly, a carrier assembly, an adhesive assembly, a display assembly, and a lifting assembly. The support assembly is symmetrically arranged on both sides, and each of the two sets of support assemblies has a carrier assembly for placing the component on its surface. The carrier assembly has an adhesive assembly for positioning the material on its surface. This invention solves the problem of the lack of an effective method to evaluate the hydrophilicity and hydrophobicity of the inner surface of hollow fiber dialysis membranes by coordinating the components, carrier assembly, adhesive assembly, display assembly, lifting assembly, and stopwatch. The testing method is simple and effective, requiring no special tools or equipment. This testing method and fixture can meet the requirements for rapid evaluation of the contact angle of the inner surface of hollow fiber membranes at the micron level. The testing method is simple, the testing cost is low, and the test results have high reliability. Therefore, it can be used as an evaluation tool for the hydrophilicity and hydrophobicity of the inner surface of hollow fiber membranes.

The invention discloses a preparation method of an oxapyrazine capsule, which comprises the following steps: 1) preparing a primary suspension: dissolving a polymer carrier material in an organic solvent, and dissolving oxapyrazine in the solution to obtain an oil phase; adding a surfactant into the purified water to obtain a water phase; dropwise adding the oil phase into the water phase, and stirring by using a stirrer to prepare a primary suspension; 2) preparing a nano suspension: performing emulsification treatment by an ultrasonic processor to prepare the nano suspension; removing the organic solvent in a manner of reduced pressure evaporation or dialysis with a dialysis membrane to leave an oxapyrazine nanoparticle suspension; 3) preparation of the oxapyrazine capsule: drying the nano suspension prepared in the step 2) by a freeze drying method or a spray drying method to obtain oxapyrazine nano particles in a solid powder form, and the final average particle size is 300 + / -60nm; and filling a capsule shell with the prepared oxapyrazine nanoparticle powder to prepare the oxapyrazine capsule. The sustained release time of the oxapyrazine capsule prepared by the method is obviously prolonged.

The application discloses a kind of roll type diffusion dialysis membrane module and preparation method thereof, including cylinder, U-shaped tube;U-shaped tube straight pipe part upper end is connected respectively with the inlet and outlet pipe of diffusion liquid and dialysate;Wherein, between a pair of diagonal straight pipe parts, ion exchange membrane is equipped, and both sides of ion exchange membrane are equipped with a flow channel screen, above the pair of diagonal straight pipe parts, by ion exchange membrane and flow channel screen, spiral is wound into cylinder by mutual close, and the end of ion exchange membrane and flow channel screen winding is fixed on another pair of straight pipe parts respectively;Space supported by flow channel screen constitutes fluid channel and is always located at both sides of ion exchange membrane, one side constitutes diffusion liquid flow channel and is connected with a pair of diffusion liquid inlet and outlet connector communication, the other side constitutes dialysate flow channel and is connected with a pair of dialysate inlet and outlet connector communication, the application solves the problem that liquid inlet and outlet are difficult to set when multiple membrane modules are commonly processed in higher integrated degree and mass transfer efficiency is lower.

The application discloses an ultrafiltration permeation regulation method and device based on a gradient sponge structure dialysis membrane and relates to the technical field of hemodialysis. An intelligent response membrane assembly containing a nonlinear aperture gradient is constructed; a signal is collected and a concentration polarization critical index is calculated; when the threshold value is exceeded, a multi-frequency coupling pulse control instruction containing a mechanical resonance excitation waveform and a phase reverse matching osmotic pressure oscillation waveform is generated; mechanical resonance excitation is applied to the blood side to induce membrane layer micro-breathing deformation, and an osmotic pressure oscillation waveform is injected into the dialysate side to form a reverse solute diffusion field; microgel deformation feedback signals are monitored in real time, waveform parameters are dynamically adjusted, and the concentration polarization critical index is returned to a safe interval until the ultrafiltration flux is adaptively regulated. The device comprises an intelligent gradient membrane assembly, a fluid power regulation module, an osmotic pressure wave generation module, a sensing feedback array and a central processing unit, can effectively inhibit membrane pollution and concentration polarization, and improves the system operation stability.

The invention discloses a bionic modification method of a hemodialysis membrane and application of the bionic modification method, and belongs to the technical field of medical materials.The method comprises the steps that vinylbenzylamine and vinyltriethoxysilane are dissolved in triethyl phosphate to be stirred, an initiator azodiisobutyronitrile is added, and heating polymerization is conducted to obtain a polymer [P (EP-VTES)]; carrying out amidation reaction to form a gallic acid functional polymer (Ga-EPTES); ga-EPTES is cross-linked to the surface of a polyethersulfone membrane in a monomolecular layer form, and the hemodialysis membrane with the functions of resisting oxidation and removing free DNA is prepared. According to the bionic modification method of the hemodialysis membrane, the functional limitation and modification defects of a traditional blood purification material are broken through, an efficient, safe and large-scale solution is provided for sepsis treatment, and the bionic modification method has scientific value and clinical transformation potential.

This invention discloses a method for preparing a blood purification dialysis membrane and its application, relating to the field of materials preparation technology. The method includes the following steps: S1, dissolving polyacrylonitrile powder in N-N-dimethylformamide solvent to obtain a PAN spinning solution; S2, spinning the PAN spinning solution using electrospinning to obtain a PAN nanofiber membrane; S3, depositing a multi-walled carbon nanotube solution into the interfiber gaps of the PAN nanofiber membrane to obtain a composite PAN nanofiber membrane; S4, subjecting the composite PAN nanofiber membrane to hot-pressing treatment to obtain the blood purification dialysis membrane. By combining electrospinning with multi-walled carbon nanotube deposition and hot-pressing processes, a composite membrane with a gradient pore size structure is constructed. This effectively removes small and medium-sized toxins while selectively retaining large-molecule proteins, solving the technical challenges of wide pore size distribution and difficulty in balancing toxin removal and protein retention in traditional dialysis membranes. It offers the advantages of precise membrane structure control and improved blood purification efficiency.

The invention belongs to the technical field of ceramic precursors, and particularly relates to a silicon-boron-carbon-nitrogen ceramic precursor with a main chain containing alkynyl and a preparation method of the silicon-boron-carbon-nitrogen ceramic precursor. Comprising the following steps: (1) dropwise adding an n-butyllithium solution into an ether solvent, stirring, continuously dropwise adding trichloroethylene, and reacting to obtain an alkynyl dilithium salt turbid solution; (2) adding boron trichloride into the alkynyl dilithium salt turbid solution to carry out primary dechlorination polycondensation reaction, and dropwise adding dichlorosilane to carry out secondary dechlorination polycondensation reaction after the reaction is completed; (3) adding hexamethyldisilazane into the system in the step (2) to carry out an end-capping reaction, collecting supernate after the reaction is finished, and distilling at normal pressure to remove the solvent, so as to obtain a silicon-boron-carbon-nitrogen ceramic precursor crude product; and (4) dissolving the silicon-boron-carbon-nitrogen ceramic precursor crude product in an organic solvent, carrying out dialysis treatment, and carrying out atmospheric distillation on the solution in a dialysis membrane to remove the solvent so as to obtain the silicon-boron-carbon-nitrogen ceramic precursor with the main chain containing alkynyl, and the ceramic yield of the silicon-boron-carbon-nitrogen ceramic precursor in the high-temperature ceramization process can reach more than 70%.

The invention discloses a modified cellulose acetate dialysis membrane and a preparation method thereof.The preparation method comprises the following steps that after a cellulose acetate membrane is hydrolyzed for 1 min, the acetyl part of the cellulose acetate membrane is removed, then the cellulose acetate membrane with the acetyl part removed is subjected to an oxidation reaction, and the cellulose acetate membrane with the acetyl part removed is obtained; a selective oxidation catalyst A and / or a co-catalyst B are / is used in the oxidation reaction process, and an oxidant C is one of sodium hypochlorite, sodium chlorite, calcium hypochlorite, hydrogen peroxide, persulfate or sodium periodate; and then adding chitosan which is subjected to crosslinking modification by dialdehyde cellulose to carry out grafting reaction. According to the method, the grafting effect can be optimal only through the synergistic cooperation of the carboxyl active site amount and the crosslinking degree of the chitosan, and the urea adsorption capacity and the blood compatibility of the cellulose acetate membrane are remarkably improved.

This invention discloses a polyethersulfone, its preparation method, and its applications. The polyethersulfone satisfies the following formula: x = A1 / (A1+A2) < 6%; where A1 is the integral area occupied by the weight-average molecular weight of not less than 200,000 g / mol in the GPC spectrum, and A1 is denoted as the high molecular weight peak area; A2 is the integral area occupied by the weight-average molecular weight of less than 200,000 g / mol in the GPC spectrum, and A2 is denoted as the main peak area. The polyethersulfone prepared by this invention exhibits a bimodal molecular weight distribution, with the main peak area accounting for more than 90%. The main peak molecular weight can be controlled, and the weight-average molecular weight is between 60,000 and 180,000 g / mol, which can meet the performance requirements of applications such as hemodialysis membranes.

The invention discloses a cleaning device for circulating liquid in an organ perfusion system, relates to the technical field of organ culture, and solves the problems that a traditional cleaning device interferes with main circulation, waste removal is not thorough, and perfusion is broken during maintenance. The perfusion system body comprises an aorta side / portal vein side liver inlet pipeline, a liver outlet liquid return pipeline, a liquid storage bag, an organ container and a four-pump body assembly, the double liver inlet pipelines are in butt joint with a liver aorta and a portal vein respectively, and the liver outlet pipeline is connected with the liquid storage bag through a third pump body; the cleaning device comprises a filter which is connected with the liquid storage bag in parallel and connected with a fourth pump body in series to form auxiliary circulation, the filter is divided into first-stage permeation filtration and second-stage dialysis membrane filtration, and a bypass pipeline with a valve / three-way switch is further arranged; the device ensures the stability of main circulation, efficiently removes waste in a grading manner, does not interrupt perfusion during maintenance, and assists in maintaining the in-vitro activity of organs.

The invention relates to the technical field of biomedical materials, in particular to an anticoagulation hemodialysis membrane, a base material of the anticoagulation hemodialysis membrane is polysulfone or polyethersulfone, the anticoagulation hemodialysis membrane is of a porous asymmetric structure, and the inner wall surface, making contact with blood, of the hemodialysis membrane is of a bionic micro-nano composite structure. The structure comprises micron-sized bulges and nano-sized particles distributed on the surfaces of the micron-sized bulges, a zwitterionic polymer is covalently grafted on the surface of the micro-nano composite structure and the inner wall of a membrane pore channel; heparin molecules are covalently bonded to the tail end of the zwitterionic polymer. According to the anticoagulant hemodialysis membrane, the anticoagulant performance is qualitatively improved while the excellent mechanical strength, solute clearance rate and ultrafiltration performance of a traditional polysulfone membrane are kept.

The application discloses an antibacterial nanofiber hemodialysis membrane and a preparation method thereof, and relates to the technical field of dialysis membranes, and comprises the following process: a surface treatment agent is obtained by mixing a chitosan derivative, heparin, dopamine, an unsaturated monomer and an initiator in a DMF / phosphate buffer mixture; a polyethersulfone nanofiber membrane is taken as a support layer, the surface treatment agent is impregnated, UV irradiation is performed, and a functional layer is formed to obtain a dialysis membrane. The application compounding cerium tris-acrylate phenanthroline hybrid CeO2, N-vinyl pyrrolidone, sodium p-styrene sulfonate and lauryl methacrylate as the unsaturated monomer, compounding the chitosan derivative, heparin and dopamine to prepare the surface treatment agent, impregnating the polyethersulfone nanofiber membrane, and performing irradiation and solidification to form the functional layer, the prepared hemodialysis membrane has high efficient anticoagulation and broad-spectrum antibacterial property, high permeability, low protein adsorption and long-term stability.

A method of synthesizing carbon quantum dots (CQDs) includes using a dried ground Halodule uninervis seagrass to form a suspension in water, followed by centrifuging and filtering through a filter membrane and a dialysis membrane to form a CQDs solution. The CQDs have a Stokes shift of less than 83.0 nm at an excitation wavelength of 380 to 430 nm.

The utility model discloses anode oxidation tank solution's processing system, including clarification membrane group, diffusion dialysis membrane group, concentration membrane group and clear liquid storage tank, the clarification membrane group has ultrafiltration membrane, the clarification membrane group handles anode oxidation tank solution and exports first thick liquid and first permeate, the diffusion dialysis membrane group has selective ion membrane, the diffusion dialysis membrane group handles first permeate and clear liquid and exports second thick liquid and second permeate, the clear liquid import of diffusion dialysis membrane group and the water outlet of clear liquid storage tank intercommunication, the concentration membrane group has nanofiltration membrane, the concentration membrane group handles second thick liquid and exports third thick liquid and third permeate, the third permeate export of concentration membrane group and the water inlet of clear liquid storage tank are linked to. The utility model has realized the effective separation and recycling of acid component and metal ion in anode oxidation tank solution.

The invention discloses a device for detecting human blood protein binding activity and a detection method, and aims to solve the problems that the existing equilibrium dialysis method is too long in time consumption and tedious in operation. The device comprises a pressure dialysis tube assembly, a pressure control module and a temperature control module. The pressure dialysis tube assembly is provided with a dialysis membrane which can intercept human serum albumin in a sample chamber and allow free small molecule ligands to pass through. The pressure difference between the pressure air inlet and the pressure balance port is accurately adjusted through the pressure control module, zero pressure difference can be kept in the combination stage to prevent leakage, positive pressure is applied in the dialysis stage to drive free ligands to quickly pass through a dialysis membrane, and the separation time is greatly shortened. The temperature control module ensures that the whole process is in a constant-temperature environment, and physiological correlation and repeatability of data are ensured. The detection method comprises the steps of sample mixing, constant-temperature combination, pressure dialysis, dialysate collection, ultraviolet spectrophotometry determination and the like. According to the invention, rapid, accurate and high-throughput detection of the binding activity is realized.

The application discloses a preparation method of pH-sensitive long-wave carbon dots and application of the carbon dots in fluorescent ink, and belongs to the technical field of carbon nanomaterials. The application is characterized in that neutral red and L-cysteine are ultrasonically dissolved in deionized water at room temperature, then a heating reaction is carried out, the solution is naturally cooled to room temperature and filtered, and then the carbon dots aqueous solution is obtained by dialysis through a dialysis membrane, and L-CDs are obtained by freeze-drying. The L-CDs prepared by the application have high sensitivity in non-labeled detection of pH and hypochlorite, low cost, a simple detection process, small harm to biological samples, and are more safe and reliable. The L-CDs can also be used for intracellular imaging.

The two-dimensional carbon quantum dot production machine with an automatic continuous system is designed for synthesizing two-dimensional carbon quantum dots, namely graphene oxide quantum dots or reduced graphene oxide quantum dots, within a single integrated device, using graphene oxide or reduced graphene oxide as the precursor material. The primary structure of the carbon quantum dot production machine comprises an external main frame for placing synthesis equipment, shaped as a tall rectangular box, with wheels installed at all four bottom corners for mobility. The machine includes a control cabinet and an operating control system powered by a processing unit, along with a wet air filtration system. The external main frame is equipped with various components including a deionized water tank used in the production process, a chemical oxidation reaction tank with temperature control and a magnetic stir bar for agitation during the reaction, a pH monitoring system, and a condenser unit to condense vapors from the reaction back into liquid. It also includes a high- frequency ultrasonic reaction tank with temperature control via water flow through coiled tubing wrapped around the container, a dual-stage filtration system consisting of a coarse filter and a fine filter, and a purification system using a dialysis membrane bag. The machine is equipped with a water valve system for flow control, a stirring system with paddle blades, and a product storage tank for collecting the purified carbon quantum dots.

The application provides a hydrophilic modified cellulose ultrafiltration membrane and a preparation method thereof, physical dissolution of cellulose is carried out by using a good solvent NMMO.H2O of cellulose, natural characteristics of the cellulose are retained more, and the prepared flat membrane or hollow fiber membrane shows good mechanical properties and acid and alkali resistance; modified cellulose is prepared by using an oxidant oxidation and chemical modification technology, crystallinity of the cellulose membrane can be effectively reduced, hydrophilicity is improved, water flux of the cellulose membrane is improved, and the anti-pollution ability is improved, the membrane preparation process is simple, the solvent NMMO.H2O is easy to recycle, and the process is green and environment-friendly; the modified cellulose ultrafiltration membrane prepared by the application has very strong hydrophilicity, high flux and strong anti-pollution ability, is suitable for liquid separation fields, such as water treatment, food fields or separation of polar and non-polar liquid alcohol and ketone mixtures in the field of pervaporation, and has good application prospects in medical dialysis, membrane extraction, membrane absorption and the like.

The invention discloses a preparation method of fruit wine, and particularly aims to solve the problem of mutual exclusion of plant lactobacillus and saccharomyces cerevisiae in low-acid fruit juice fermentation. The method adopts the following core processes: (1) strain combination: selecting plant lactobacillus L14 and saccharomyces cerevisiae NX11424 which are proved to be capable of realizing efficient symbiosis with saccharomyces cerevisiae under a physical isolation condition through screening and realizing deep degradation of malic acid and efficient synthesis of lactic acid; (2) physical isolation: separating the double bacteria through a dialysis membrane with the molecular weight cut-off of 10 kDa, blocking the inhibition effect of the yeast on the plant lactobacillus caused by direct contact of thalli, and allowing free exchange of small molecular metabolites such as organic acids and saccharides; (3) synchronously inoculating, namely simultaneously inoculating the two bacteria into low-acid fruit juice (the initial pH is greater than or equal to 4.5, and the total acid is less than or equal to 3g / L), and fermenting at 25 DEG C in a dark place; the antagonism of mixed bacteria fermentation is relieved, high-activity symbiosis of double bacteria is guaranteed, malic acid degradation and lactic acid efficient synthesis are synchronously realized, the acid feeling balance degree of the fruit wine is remarkably improved, and flavor loss is also avoided.

The invention discloses a dialyzer membrane rupture detection device and a control method, which are used for detecting a dialysis membrane when a user performs dialysis, and comprise a dialysate supply module, a pre-penetration pump, a balance cavity, a post-penetration pump, an electromagnetic valve group, a first pressure sensor, a dialyzer connection module and a control module, the dialyzer connecting module is provided with a liquid supply port and a liquid return port; dialysate is connected with a dialyzer through a dialysate supply module, a pre-penetration pump, a balance cavity, an electromagnetic valve group and a dialyzer connecting module, so that the dialyzer flows back to a post-penetration pump through the electromagnetic valve group and is discharged; the opening and closing of the electromagnetic valve group can be controlled by the control module according to a preset program, so that pre-filling and sealing detection can be realized, and an automatic and closed-loop membrane rupture test can be completed. Compared with a manual visual method or a simple leak detection method, the method has the advantages that the detection accuracy and repeatability are improved, manual operation errors are reduced, recording and tracing are facilitated, and the clinical use safety and working efficiency are improved.

The utility model relates to a kind of crosslinked sodium hyaluronate gel dialysis devices, including reaction cylinder, the sliding seat of evenly distributed is fixedly connected in the reaction cylinder inner wall, the first silica gel hose of two groups is fixedly connected in the reaction cylinder inner wall, the one end of the first silica gel hose away from reaction cylinder is fixedly connected with valve.The utility model in the present application, the rotating of the sliding block and spring telescopic rod in the steel frame inner wall is driven by the setting rotating sleeve, the special structure of its sliding block rotation is clamped into the recess when rotating to the recess of clamping seat by guide plate, to realize the position fixing of L-shaped plate, the rotation angle is all flat angle, to facilitate the position of the position of L-shaped plate rotation to the position limiting of steel frame, even after carrying dialysis membrane bag and being hung in reaction cylinder, the problem of the gel quantity of dialysis in prior art is solved, dialysis membrane bag is not inconvenient to put in and take out.

According to the gas-liquid double-channel hollow fiber perfusion culture system and method, a gas exchange module comprises a plurality of hollow fiber oxygenation membranes, gas channels are formed in the hollow fiber oxygenation membranes, the outsides of the hollow fiber oxygenation membranes are in direct contact with a tissue engineering scaffold culture solution, and dissolved oxygen transmission is achieved through diffusion; the liquid perfusion module comprises a plurality of hollow hemodialysis membranes, culture solution channels are formed in the hollow hemodialysis membranes, the exteriors of the hollow hemodialysis membranes are in direct contact with a tissue engineering scaffold culture solution, and nutrient substance transmission is achieved through diffusion; the monitoring module is used for monitoring key parameters of a tissue engineering scaffold culture solution in real time and can automatically feed back and adjust the gas flow and the liquid flow rate according to monitored data, and the gas-liquid double-channel hollow fiber perfusion culture system has the oxygen supply capacity and the three-dimensional perfusion function; the survival rate and functional expression of cells in the scaffold can be improved, and the stability of a tissue structure can be maintained in vitro for a long time.

The application discloses an ultrafiltration permeation regulation method and device based on a gradient sponge structure dialysis membrane and relates to the technical field of hemodialysis. An intelligent response membrane assembly containing a nonlinear aperture gradient is constructed; a signal is collected and a concentration polarization critical index is calculated; when the threshold value is exceeded, a multi-frequency coupling pulse control instruction containing a mechanical resonance excitation waveform and a phase reverse matching osmotic pressure oscillation waveform is generated; mechanical resonance excitation is applied to the blood side to induce membrane layer micro-breathing deformation, and an osmotic pressure oscillation waveform is injected into the dialysate side to form a reverse solute diffusion field; microgel deformation feedback signals are monitored in real time, waveform parameters are dynamically adjusted, and the concentration polarization critical index is returned to a safe interval until the ultrafiltration flux is adaptively regulated. The device comprises an intelligent gradient membrane assembly, a fluid power regulation module, an osmotic pressure wave generation module, a sensing feedback array and a central processing unit, can effectively inhibit membrane pollution and concentration polarization, and improves the system operation stability.

This invention discloses a method and apparatus for solute removal in hemodialysis with precise membrane pore size control, belonging to the field of blood purification technology. The method involves introducing blood and dialysate into both sides of a dynamically controlled bilayer heterostructure dialysis membrane, collecting characteristic signals of metabolic solutes and plasma functional proteins in the blood, inputting these signals into an adaptive pore size decision model, and outputting target pore size and electric field strength parameters. A low-frequency alternating electric field drives reversible conformational changes in stimulus-responsive polymer chains within the membrane, achieving precise control of the membrane channel's effective sieving pore size, locking the pore size within a threshold range where small molecule solutes permeate while plasma functional proteins are completely retained. Combining axial gradient channels and radial charge sieving mechanisms within the membrane achieves graded and targeted solute removal. A piezoelectrically driven periodic micro-pulsating flow field removes the fouling layer from the membrane surface, improving mass transfer stability. This invention automates and precisely controls the dialysis process, improving solute removal efficiency and plasma protein protection.

The invention discloses a surface-modified low-pass hemodialysis membrane as well as a preparation method and application thereof, and belongs to the technical field of hemodialysis membranes. The dialysis membrane comprises a base membrane and a modified coating located on the inner surface of the base membrane. The base membrane is a polyether sulfone hollow fiber membrane; the modified coating is of a two-dimensional net structure formed by an aminobenzene substance and an aldehyde substance containing a sulfonic acid group through a polymerization reaction, and the average pore diameter of the structure is 1.5-1.8 nm. Furthermore, the invention also provides a preparation method of the surface-modified low-pass hemodialysis membrane and application of the surface-modified low-pass hemodialysis membrane in a hemodialyzer. The hemodialysis membrane provided by the invention has the advantages that the hemodialysis membrane has a low ultrafiltration coefficient, so that the hemodialysis membrane still keeps relatively high toxin removal efficiency on the premise of low transmembrane and low ultrafiltration coefficient, and has relatively good biocompatibility.

The invention relates to a preparation method of lithium hydroxide, in particular to a preparation method of high-purity lithium hydroxide. More specifically, the invention relates to a preparation method of lithium hydroxide, which comprises the following steps: adding a lithium salt aqueous solution into a salt chamber between an anion dialysis membrane and a cation dialysis membrane adjacent to each other in a bipolar electrodialysis device, adding an acid chamber reaction solution into an acid chamber between a bipolar membrane and the anion dialysis membrane, and carrying out electrodialysis to obtain the lithium hydroxide. Adding an alkali chamber reaction solution into an alkali chamber between the bipolar membrane and the cation dialysis membrane; supplying the desalted solution formed in the salt chamber to a salt tank, supplying the acid solution formed in the acid chamber to an acid tank, and supplying the lithium hydroxide solution formed in the alkali chamber to an alkali tank; and circularly supplying the desalinized solution of the salt tank to the salt chamber, circularly supplying the acid solution of the acid tank to the acid chamber, and circularly supplying the lithium hydroxide solution of the alkali tank to the alkali chamber, the gauge pressure of the salt chamber being higher than the gauge pressure of the acid chamber.