215results about How to "Uniform shape" patented technology

The invention relates to a universal nano biological vesicle preparation method. The preparation method comprises the following steps: carrying out crude extraction on cells from bacteria, fungi, plants or animals to obtain a crude extracting solution; the crude extracting solution is placed in a low-temperature and high-pressure homogenizer to be subjected to low-temperature and high-pressure homogenizing treatment, then the nano vesicles are obtained, the low-temperature and high-pressure homogenizer comprises a high-pressure cavity, a homogenizing valve, a working cavity, a conveying system and a temperature control system, a slit is formed in the homogenizing valve, and the crude extracting solution located in the high-pressure cavity enters the working cavity through the slit of the homogenizing valve, the pressure intensity of the high-pressure cavity is 300-3000 bar, and the working temperature of the high-pressure homogenizer is 0-10 DEG C. The activation energy is reduced by controlling high-pressure and low-temperature environments, so that the original cell membrane structure is broken, the cell wall structure is destroyed, and phospholipid bimolecules are driven to aggregate and self-assemble to form the vesicles. For biological membranes derived from bacteria, fungi, plants and animals, the vesicles can be prepared by the preparation method disclosed by the invention, and the method has universality.

The invention belongs to the technical field of bridge expansion joint welding, and particularly relates to a bridge expansion joint welding fixing device with a limiting mechanism, which comprises a welding seat, a processing seat fixed on the surface of the welding seat and bridge expansion joint profile steel attached to two sides of the surface of the processing seat, and a limiting assembly is mounted on the surface of the welding seat. The device is provided with the limiting assembly, the position of the bridge expansion joint profile steel can be effectively limited, it is guaranteed that the bridge expansion joint profile steel is kept in a stable state in the welding process, the welding quality can be better improved, and welding defects caused by position deviation of the bridge expansion joint profile steel are reduced; according to the bridge expansion joint profile steel limiting device, collision or damage caused by displacement of the bridge expansion joint profile steel is reduced, meanwhile, the bridge expansion joint profile steel is pressed and limited through the pressing plates at the four corners, limiting force can be applied to the bridge expansion joint profile steel in multiple directions, the overall limiting effect is enhanced, the profile steel can better resist external force interference in the welding process during welding, and the welding quality of the profile steel is improved. And smooth welding is ensured.

The invention discloses a ferric sodium pyrophosphate positive electrode material, a preparation method thereof and a battery, and relates to the technical field of batteries. Pre-sintering is performed; sanding and spray drying; and high-temperature sintering. Wherein the pH value of the reaction is controlled by using a Tris-HCl buffer solution in the hydrothermal reaction, so that the precursor is uniformly crystallized and has high crystallinity, and low-temperature segmented presintering is adopted later, so that the compaction density of the material can be controlled, and the related electrical properties of the material are relatively good. In the preparation process, a carbon source and a doping element are supplemented twice, so that carbon coating is uniform in the sintering process, the compaction density of the NFPP positive electrode material is further improved, the properties such as theoretical specific capacity of the positive electrode material are better through doping and carbon coating modification, and the high-compaction and high-capacity ferric sodium pyrophosphate positive electrode material is obtained.

The invention belongs to the technical field of whisker material growth and ceramic substrate preparation, and discloses a preparation method of an aluminum nitride whisker and a high-strength and high-thermal-conductivity ceramic substrate, and the preparation method of the aluminum nitride whisker comprises the following steps: mixing aluminum powder serving as a raw material and ammonium salt serving as an inducer according to a mass ratio of (2: 1)-(1: 2); and carrying out heat preservation for 0.5-2 hours at the temperature of 800-1100 DEG C under the nitrogen and / or ammonia atmosphere condition, and carrying out nitridation reaction. According to the invention, a whisker and ceramic substrate synthesis method is improved, aluminum nitride whiskers with uniform morphology and length-diameter ratio are controllably synthesized through a rapid nitriding method, and the aluminum nitride whiskers and spherical aluminum nitride are sintered only by taking the aluminum nitride whiskers as an additive without the participation of additional sintering aids and reinforcers, so that the ceramic substrate is obtained. The high-strength and high-thermal-conductivity aluminum nitride ceramic substrate is obtained and has high mechanical strength and thermal conductivity.

The invention discloses a preparation method of a zinc-dihydromyricetin nano-enzyme and application of the zinc-dihydromyricetin nano-enzyme in preparation of drugs for promoting healing of diabetic wounds, and the zinc-dihydromyricetin metal polyphenol nano-enzyme (Zn-DHM) is obtained by coordinating a metal element zinc (Zn) and a natural product dihydromyricetin (DHM) through a one-step method by taking PVP as a surfactant. The Zn-DHM nano-enzyme prepared by the invention has antioxidant property and cell proliferation and migration promoting ability, and can maintain metabolism and immune homeostasis of diabetic wounds, so that the Zn-DHM nano-enzyme can accelerate early healing of the diabetic wounds.

The invention provides an Mxene-iron molybdenum bimetallic sulfide and carbon composite material as well as a preparation method and application thereof, belongs to the technical field of sodium ion batteries, and is used for solving the technical problems of poor conductivity and rate capability of a metal sulfide negative electrode material. The preparation method of the Mxene-iron-molybdenum bimetallic sulfide and carbon composite material comprises the following steps: dissolving an iron source, a molybdenum source and a carbon source in a solvent to prepare a mixed solution; then carrying out a hydrothermal reaction to prepare a bimetallic oxide nanosphere; the bimetallic oxide nanospheres are subjected to high-temperature vulcanization treatment, and iron-molybdenum bimetallic sulfide carbon is prepared; the preparation method comprises the following steps: mixing Mxene and iron-molybdenum bimetallic sulfide and carbon through ball milling to prepare the Mxene-iron-molybdenum bimetallic sulfide and carbon composite material. The composite material disclosed by the invention can realize efficient electron transmission and provide more active sites, and is beneficial to the electrochemical reaction of the battery; the mechanical stability of the material can be enhanced, the volume expansion in the charging and discharging process is effectively reduced, the particle diffusion path between positive and negative electrodes is shortened, and the reaction kinetics of the electrode is improved; and the conductivity and the rate capability of the material can be effectively improved, so that the comprehensive performance of the sodium-ion battery is improved.

The invention discloses a preparation method and sodium storage application of a sodium-enriched sodium ferric sulfate composite material. The preparation method comprises the following steps: carrying out low-speed ball milling on iron-based sulfate and dispersed CNTs (Carbon Nanotubes), carrying out vacuum drying, carrying out heat treatment, and naturally cooling to room temperature to obtain FeSO4 / CNTs; the preparation method comprises the following steps: mixing FeSO4 / CNTs and anhydrous Na2SO4 according to a molar ratio of Na to Fe of 7: 5.5, carrying out low-speed wet ball milling, carrying out vacuum drying, and grinding to obtain Na2SO4 / FeSO4 / CNTs; and compacting Na2SO4 / FeSO4 / CNTs, placing the Na2SO4 / FeSO4 / CNTs in a tubular furnace, preserving heat at 350-400 DEG C for 10-24 hours, cooling to room temperature, and grinding to obtain the Na7Fe5.5 (SO4) 9 / CNTs composite material. The Na7Fe5.5 (SO4) 9 positive electrode material disclosed by the invention has good sodium storage specific capacity, excellent rate capability and stable long cycle life.

The invention discloses a V-shaped mud cabin drag suction dredger pumping channel structure which comprises a connecting pipe, a mud cabin pumping channel and a bow square rotating circle, one end of the mud cabin pumping channel is connected with one end of the connecting pipe, and the other end of the mud cabin pumping channel is connected with a mud pipe of a bow through the bow square rotating circle. The top face of the mud cabin pumping channel is of a double-top structure, the inner wall of the double-top structure, the inner side face of the mud cabin pumping channel and the inner bottom face of the mud cabin pumping channel are all smooth faces, the bottom structure of the mud cabin pumping channel is of a longitudinal continuous structure, and the bottom structure of the mud cabin pumping channel separates a mud door hinge point and rubber and provides support above the rubber. The double-top structure comprises a double-top structure lower top plate and a double-top structure upper top plate located above the double-top structure lower top plate. The upper portion of the double-top structure lower top plate is fixedly connected with the double-top structure upper top plate through rib plates or reinforcing ribs. The structure is few in hard points, uniform in channel shape, small in resistance, simple in construction process, high in pumping efficiency, safe and reliable. No protruding structure exists in the mud cabin, and mud unloading is smooth.

The invention discloses a preparation method of a multilayer flexible electromagnetic shielding film. The method comprises the following steps: (1) pretreating a polyethylene glycol terephthalate fabric; (2) activating the pretreated PET fabric; (3) preparing a chemical nickel-plating solution and a chemical copper-plating solution, and respectively putting the PET fabric activated in the step (2) into the chemical nickel-plating solution and the chemical copper-plating solution to respectively obtain a PET nickel-plated fiber fabric (PET / Ni) and a PET copper-plated fiber fabric (PET / Cu); (4) respectively washing the PET / Ni and the PET / Cu obtained in the step (3) with deionized water, and drying the PET / Ni and the PET / Cu; and (5) performing hot pressing on PET / Ni and PET / Cu obtained in the step (4), using an aluminum foil as a substrate, arranging an upper stainless steel plate and a lower stainless steel plate, and performing natural cooling to room temperature after hot pressing to obtain the multi-layer flexible electromagnetic shielding film. The material has good mechanical properties and excellent thermal stability, and has the characteristics of simple process and low cost.

The utility model discloses an aluminum composite wire straightening device which comprises a bottom plate, a support plate is fixedly connected to the surface of one side of the bottom plate, a base frame is fixedly connected to the surface of one side of the support plate, a straightening assembly is movably connected to the upper end of the base frame, and a traction assembly is fixedly connected to the surface of one side of the bottom plate. And a rear rack is arranged at the upper end of the traction assembly. The first motor works to drive the rotating rod to rotate, the rotating gear drives the rotating ring to rotate through the gear groove, the roller swing support freely rotates at a limited angle at the upper end of the connecting plate, and the two straightening rollers can rotate by 360 degrees around an aluminum composite wire rod to straighten the aluminum composite wire rod while freely rotating at the limited angle. The three straightening assemblies are used for carrying out straightening treatment on the wire rod in a sectional mode in sequence, through 360-degree pressing straightening, it is ensured that the wire rod is evenly pulled and straightened in all directions, the overall shape of the wire rod is more uniform, possible distortion or deformation is reduced, and therefore the quality and reliability of products are improved.

The invention relates to the technical field of integrated circuit chip packaging, in particular to an integrated circuit chip processing and packaging device and a packaging method thereof. Comprising a workbench, two sets of sliding grooves are symmetrically formed in the workbench, a first threaded rod is rotationally connected into one set of sliding grooves, and the first threaded rod is in transmission connection with a glue sealing assembly; the workbench is fixedly connected with a glue guide mechanism; the glue sealing assembly comprises two sets of movable supports, a second threaded rod is rotationally connected between the two sets of movable supports, and the second threaded rod is in threaded connection with a glue outlet mechanism. A plurality of integrated circuit chips are placed on a slide holder, clamping of the slide holder and a glue guide mechanism is completed, the integrated circuit chips are fixed in a glue injection space, and a first threaded rod and a second threaded rod drive a glue outlet mechanism to perform transverse and longitudinal intermittent movable glue injection until glue injection operation on all the integrated circuit chips is completed.

The invention discloses a SnO2 modified WO3 nanosheet composite gas-sensitive material as well as a preparation method and application thereof, and belongs to the technical field of inorganic composite materials. The preparation method comprises the following steps: dissolving WCl6 in ethanol, adding into a reaction kettle provided with a ceramic tube, carrying out hydrothermal reaction at 170-190 DEG C for 5-8 hours, taking out the ceramic tube, drying, and annealing to obtain a ceramic tube loaded with WO3 nanosheets; the preparation method comprises the following steps: dissolving SnO2, tin chloride and urea in water to obtain a mixed solution, adding the mixed solution into a reaction kettle filled with a ceramic tube loaded with a WO3 nanosheet, carrying out a hydrothermal reaction at 90-100 DEG C for 1-4 hours, taking out the ceramic tube after the reaction is finished, and drying to obtain the SnO2 modified WO3 nanosheet composite gas sensitive material, and enabling the SnO2 modified WO3 nanosheet to grow on the ceramic tube in situ. The preparation method is simple, the product is high in crystallinity and good in stability and is suitable for preparing a gas sensitive sensor material with high economical efficiency, and a sensor prepared from the SnO2 modified WO3 nanosheet composite gas sensitive material can effectively improve the gas sensitive performance of WO3 and shows an extremely high response value to nitrogen dioxide at a low temperature.

The invention discloses a near-infrared light response ultrathin nanosheet sulfur-doped BiOCl photocatalyst as well as a preparation method and application thereof, and belongs to the technical field of photocatalytic materials. The preparation method comprises the following technical steps: (1) preparing a BiOCl nanosheet; and (2) preparing the sulfur-doped BiOCl nanosheet. By adopting a secondary hydrothermal method and controlling the dosage of thioacetamide and BiOCl nanosheets, the prepared catalyst is an ultrathin nanosheet with uniform morphology, the average size is 70-120nm, the catalyst has light response in a near-infrared light region of 780-1200nm, the light absorption capacity of the catalyst is better, and near-infrared light response can be achieved. The catalyst is applied to catalytic degradation of ENR, the ENR degradation rate under visible light is 66.87%, and the degradation effect is good; under near-infrared light, the ENR degradation rate is 9.25%, and the degradation performance from zero to existence is achieved. The preparation method disclosed by the invention is simple, mild in condition, easy to control, low in raw material consumption, free of complex operations such as centrifugation, low in preparation cost and easy to popularize and apply.

The invention discloses high-purity oxamide with concentrated particle size and spherical morphology, a preparation method of the high-purity oxamide and application of the high-purity oxamide in preparation of a slow-release fertilizer, and belongs to the technical field of oxamide synthesis and application. The method comprises the following steps: mixing an ammonia-alcohol solution and an alcohol ester solution, conveying the mixed solution into a series tubular reactor for reaction, and then conveying the mixed solution into a parallel tubular reactor for reaction after pressure stabilization and flow equalization to obtain a reaction solution containing oxamide; performing flash evaporation on the reaction liquid to obtain flash evaporation liquid and flash evaporation gas, and performing solid-liquid separation on the flash evaporation liquid to obtain solid oxamide and filtrate; and drying the solid oxamide to obtain the oxamide. The method realizes high conversion rate and high purity, and the product has ultrafine particle size distribution. The purity of the prepared oxamide is greater than or equal to 99%, the D50 particle size is concentrated to 50 + / -15 microns, the spherical morphology is uniform, the release is stable, and the oxamide has a very good effect in preparation of long-acting slow-release fertilizers and combustion inhibitors and research on the nitrogen utilization rate.

The invention belongs to the technical field of biochemical engineering, and particularly relates to a Pickering emulsion microcapsule of interface immobilized lipase as well as a preparation method and application of the Pickering emulsion microcapsule. The preparation method of the Pickering emulsion microcapsule comprises the following steps: ultrasonically dispersing silicon oxide nanoparticles which have an emulsifying function and can adsorb enzyme into an organic solvent to serve as an oil phase, dissolving lipase into a buffer solution to serve as a water phase, mixing the water phase and the oil phase, and carrying out ultrasonic dispersion to obtain the Pickering emulsion microcapsule. And then adding a silane coupling agent, organic amine and an organic solvent, and carrying out interface gel-sol treatment to obtain the Pickering emulsion microcapsule. The Pickering emulsion microcapsule disclosed by the invention has better high temperature resistance and pressure resistance, and can realize efficient preparation of epoxide in a fixed bed continuous enzyme catalysis olefin epoxidation reaction.

The invention discloses yttrium oxide powder and a preparation method thereof. The preparation method of the yttrium oxide powder comprises the following steps: 1) mixing an yttrium salt solution with a precipitator solution to prepare a mixed solution; wherein the molar ratio of yttrium ions in the yttrium salt to the precipitant is 1: (2-15); 2) adding C2-C5 alkanediol into the mixed solution, and reacting at the temperature of 60-160 DEG C to prepare a precipitate precursor; and 3) calcining the precipitate precursor prepared in the step 2) at 500-1200 DEG C to prepare the yttrium oxide powder. The yttrium oxide powder prepared by the method is small in primary particle size and relatively narrow in particle size distribution.

The invention relates to the technical field of medical instruments, and particularly discloses an intravascular stent. The stent is tubular and comprises a plurality of supporting rings and a plurality of connecting rods, the supporting rings are arranged at intervals in the axial direction of the intravascular stent, and every two adjacent supporting rings are connected through the corresponding connecting rod; the intravascular stent comprises a middle area and two end areas which are arranged in the axial direction, the two end areas are located at the two axial ends of the intravascular stent respectively, the middle area is located between the two end areas, the portion, located in the middle area, of the supporting ring comprises a plurality of first supporting rods connected in the circumferential direction, and the portion, located in the end areas, of the supporting ring comprises a plurality of second supporting rods connected in the circumferential direction. The width of the first supporting rod is larger than that of the second supporting rod. According to the stent, the widths of the supporting rings of all parts are limited, so that the good flexibility of the two ends of the stent is guaranteed before the stent is expanded, the supporting force of the middle is high, and the passing ability of the stent is improved; the stent is axially retracted after being expanded and is uniform in shape, so that the bone effect of a dog is reduced.

The invention discloses a slow-release temperature-controlled antifouling agent microsphere and a preparation method and application thereof, the method comprises the following steps: (1) mixing sodium alginate, copper pyrithione and a CaCl2 solution for reaction, freeze-drying, grinding and crushing to prepare intermediate product particles; and (2) mixing the intermediate product particles in the step (1) with a chitosan solution for reaction, then adding a glutaraldehyde solution for continuous reaction, and freeze-drying to obtain the antifouling agent microspheres. The sodium alginate and chitosan double-crosslinking preparation method adopted by the invention is novel, a double-layer drug-loading structure is constructed by virtue of the crosslinking effect of sodium alginate and calcium ions and the electrostatic interaction between anions and cations of sodium alginate and chitosan, and the thought is novel.

The invention discloses a microneedle patch loaded with a sorafenib and copper-doped Prussian blue nano material and application of the microneedle patch in in-situ triple-negative breast cancer treatment. The sorafenib and the copper-doped Prussian blue nano material are loaded in a needle body of the microneedle patch. The microneedle patch can accurately deliver nanoparticles and sorafenib to tumor tissues, the chemical kinetics effect is enhanced through an efficient and mild photothermal therapy, the ferroptosis of triple negative breast cancer cells is enhanced through ferroptosis induced by the nanoparticles and sorafenib in cooperation with drugs, then cell death is induced, and the curative effect is improved. And a brand-new and promising treatment method is provided for in-situ triple-negative breast cancer treatment.

The invention provides a process for preparing a high-purity human blood coagulation factor IX from plasma. The process comprises the following steps: acquiring plasma; adding anion gel, adsorbing, and collecting an eluted protein solution; adding heparin sodium, filtering, ultra-filtering and dialyzing to obtain dialyzed protein liquid; adding an S / D solution; adding anion gel for secondary adsorption, and collecting eluted protein liquid II; performing filtration, ultrafiltration and dialysis, and collecting eluted protein liquid after dialysis; filtering is performed; carrying out affinity gel chromatography purification, collecting eluent, and carrying out ultrafiltration and dialysis; filtering, and adding a dialysate containing glycine for dialysis to obtain a human blood coagulation factor IX stock solution; adjusting the titer, and adding heparin sodium to obtain a diluted solution; pre-filtering the diluted liquid to obtain a semi-finished product of the human blood coagulation factor IX; sterilizing, filtering, sub-packaging, carrying out vacuum freeze drying, carrying out dry heat virus inactivation, inspecting and packaging. According to the invention, the production process is simplified, the cost is reduced, the activity of the finally obtained human blood coagulation factor IX is greater than 50IU / ml, and the specific activity is higher than 180IU / mg.

According to the method for preparing the nanoscale carbonyl iron powder under the conditions of normal pressure and low temperature and the special integrated equipment for implementing the method, efficient cooling and nucleation of iron steam can be achieved by adopting a specially-designed micro-nano bubble generation device, and the nanoscale carbonyl iron powder which is narrow in particle size distribution, uniform in morphology and excellent in magnetic performance is prepared.

The invention relates to the technical field of nano material preparation, in particular to a zinc ion battery cathode material as well as a preparation method and application thereof. The zinc ion battery cathode material provided by the invention has the advantages of uniform shape, uniform size, high first cycle capacity and coulombic efficiency, and good cycle performance. According to the preparation method of the zinc ion battery cathode material provided by the invention, the bimetallic metal organic framework heterogeneous nanosheet material with different doping contents can be prepared by adjusting the concentration of the transition metal ions, and the activity and stability of the material are changed by changing the variety of the transition metal ions. The preparation method disclosed by the invention is also beneficial to large-scale preparation. The method does not need complex equipment, the experimental operation is simple, and macro preparation is easy. The zinc ion battery cathode material provided by the invention has important application in the aspect of electrochemical energy storage, and is helpful for improving the electrochemical performance of various types of battery electrodes.

The invention discloses a microneedle patch loaded with vancomycin and a gold / zinc cerium composite nanomaterial and application of the microneedle patch in abscess wound treatment, the microneedle patch comprises a backing layer and a needle body array arranged on the backing layer, the backing layer and the needle body array are formed by an aqueous solution of a degradable polymer, vancomycin and a gold / zinc cerium composite nano material are loaded in an aqueous solution of the degradable polymer for forming the needle body array. According to the microneedle patch disclosed by the invention, based on the photo-thermal synergistic effect of the antibiotics and the gold / zinc-cerium composite nanomaterial, rapid healing of abscess wounds is realized from the aspects of inhibiting growth of bacteria, relieving oxidative stress, promoting angiogenesis and the like.

The invention discloses a preparation method of high-specific-surface-area, high-dispersion and high-purity nano calcium carbonate, which comprises the following steps: S1, calcining limestone, digesting the lime and water in proportion, and screening to remove gravel; s2, ammonium salt or ammonia water is added into the obtained lime slurry, and the solid content is adjusted; s3, layering the lime slurry after standing, and then concentrating to obtain concentrated lime slurry; s4, putting the concentrated lime slurry into a carbonization tower, and carrying out carbonization reaction by controlling the temperature, the stirring rate, the carbon dioxide concentration and the carbon dioxide flow; s5, when over-carbonization is achieved, obtaining a nano calcium carbonate suspension; s6, standing and settling the suspension, and removing upper-layer water to enable the solid content to be within a certain range; and S7, adding stearic acid into the suspension liquid for surface modification, and carrying out filter pressing, drying, crushing and sieving on the obtained suspension liquid to obtain the nano calcium carbonate powder. The method is low in raw material cost, economical, environmentally friendly, simple in control step, short in carbonization time, high in production efficiency and convenient for industrialization.

The invention discloses a steel wire straightening machine, and relates to the technical field of steel wire straightening processing equipment, the steel wire straightening machine comprises a straightening machine base, a straightening traction assembly and a steel wire material, a straightening frame is fixedly mounted on the straightening machine base, the straightening traction assembly and the straightening frame are sequentially arranged in the direction of straightening the steel wire material, and a radial straightening shaping assembly is arranged in the straightening frame; the radial straightening and shaping assembly comprises a reciprocating screw rod rotationally connected to the bottom of the inner side of the straightening frame, a driving motor is fixedly installed on one side of the bottom of the straightening frame, the output end of the driving motor is fixedly connected with one end of the reciprocating screw rod, a reciprocating block is in transmission connection with the reciprocating screw rod, and a sleeve is fixedly installed at the top of the reciprocating block. By means of the structure, a steel wire is evenly shaped in a full-angle mode, the straightening rollers and a steel wire material are kept relatively static, the radial round shaping effect of the steel wire is improved, and abrasion between the straightening rollers and the steel wire material is reduced.

The invention provides ATP / CCS / SA-PEI aerogel as well as a preparation method and application thereof, attapulgite ATP, carboxylated chitosan CCS, polyethyleneimine PEI and sodium alginate SA are adopted as raw materials, and polymer modification and crosslinking are promoted through an ionic crosslinking method to form the aerogel. The preparation method comprises the following steps: firstly, adding a prepared CCS solution into an SA solution to obtain a CCS / SA solution; the preparation method comprises the following steps: adding a CCS solution into a reaction kettle, adding an ATP suspension, finally adding a PEI solution, uniformly mixing, pouring into a plastic mold, freeze-drying, cross-linking, washing with water, and freeze-drying again to obtain the ATP / CCS / SA-PEI aerogel. The aerogel prepared in the invention has the advantages of large specific surface area, many adsorption groups, good adsorption performance on dye pollutants and heavy metal ions, good thermal stability, reusability, and good application value in the removal of dye pollutants and heavy metal ions in sewage.

The invention belongs to the technical field of micro-nano composite materials, and particularly relates to a chromium-based bimetallic sulfide-porous carbon composite material and a preparation method and application thereof. The preparation method of the chromium-based bimetallic sulfide-porous carbon composite material provided by the invention comprises the following steps: mixing chromium salt and zinc salt, or chromium salt and manganese salt with a sulfur source, sodium gluconate and a pore-forming agent, and preparing the composite material through heat treatment and vulcanization technologies. The chromium-zinc or chromium-manganese bimetallic sulfide-porous carbon composite material prepared by the preparation method has good structural stability and conductivity, and the cycling stability of a battery can be remarkably improved when the chromium-zinc or chromium-manganese bimetallic sulfide-porous carbon composite material is used as a battery material. The prepared chromium-based bimetallic sulfide-porous carbon composite material has important application value in the field of lithium ion battery electrode materials.

The invention belongs to the technical field of drug co-delivery, and particularly relates to a nano-platform based on attenuated bacterial outer membrane vesicles and capable of achieving co-delivery of siRNA and adriamycin and a preparation method of the nano-platform. The preparation method comprises the following steps: synthesizing an ROS response type cationic polymer PTP; the preparation method comprises the following steps: preparing aptamer-DOX; preparing an ROS (reactive oxygen species) response type positive electric nano core PTP / 47aD; extracting and purifying the [delta] msbB OMVs; synthesizing a target functional unit DSPE-PEG2k-Angiopep-2 (Distearoyl Phosphate Polyethylene Glycol 2k-Angiopep-2); finally, the ROS response type co-delivery nano platform AO (at) PTP / 47aD is prepared and obtained. The co-delivery nano-platform prepared by the invention is relatively small in particle size, uniform in morphology and relatively high in biological safety, and has no obvious damage to various tissues and visceral organs. The glioblastoma immunopotentiator can be used as a general platform for gene delivery, can also be used as an immune activator, is suitable for intravenous injection administration, and can comprehensively overcome immune resistance of glioblastoma.

The invention relates to the field of chemical application, and discloses a device for preparing large-particle ammonium sulfate crystals through reduced-speed crystallization. Comprising a neutralization reactor, a settling separation tank, a pre-crystallization solution tank, a first-stage intermittent jacket crystallizer, a second-stage intermittent jacket crystallizer, a filter powder sieving device, an ammoximation tert-butyl alcohol tower reboiler, a heat exchanger group, a stirrer group and a centrifugal pump group, wherein the centrifugal pump group consists of a centrifugal pump I, a centrifugal pump II, a centrifugal pump III, a centrifugal pump IV and a centrifugal pump V; the invention further discloses a process for preparing the large-particle ammonium sulfate crystals through speed-reducing crystallization. The process comprises the following steps: adding rearrangement liquid from a caprolactam rearrangement system and gas ammonia into the neutralization reactor through an external circulation pipeline. By fully utilizing heat in a neutralization reaction and crystallization process and combining with a compound additive, a seed crystal and a speed reduction crystallization technology, an efficient two-stage series crystallization mode is realized, the generation of large-particle ammonium sulfate crystals is promoted, the crystal quality is optimized, the energy consumption is reduced and the production efficiency is improved.

The invention provides an oxygen mask optimization design method based on a finite element simulation technology. The method comprises the specific steps that S1, an oxygen mask three-dimensional model is constructed based on an obtained face model; s2, simulating the oxygen mask by using a finite element simulation technology to obtain accurate pressure distribution; and S3, optimizing the shape of the oxygen mask based on a numerical gradient method to obtain an optimal shape of the oxygen mask. The oxygen mask can be designed in a customized mode, the pressure distribution of the optimized oxygen mask is more uniform, the area of a high-pressure area is reduced, and the oxygen mask can better adapt to the face shape of a patient, so that the wearing comfort is improved, and the risk of pressure injury is reduced.