60results about How to "Uniform hole size" patented technology

The invention discloses a method for preparing silicon nitride bonding silicon carbide foamed ceramics. The method is characterized by comprising the following steps: uniformly mixing SiC, silica powder, a phenolic resin and hydroxypropyl methyl cellulose solution so as to prepare ceramic slurry; dipping the ceramic slurry on polyurethane foam, drying, and firing in a nitrogen atmosphere, thereby obtaining the silicon nitride bonding silicon carbide foamed ceramics. The silicon nitride bonding silicon carbide foamed ceramics prepared by the method are uniform in microstructure, high in strength and uniform in pore size, and residues of carbon and free silicon are avoided, so that the strength, high temperature resistance and thermal shock resistance of the ceramics can be greatly improved.

The invention relates to an electrode plate for a super capacitor and a preparation method of the electrode plate, and relates to materials for electrode components of an electrochemical capacitor. The electrode plate is made of a compound applied and pressed on a nickel screen and capable of producing MnO<2> on the surface of nano porous copper, wherein the mass percent of nano porous copper is 25 to 75. The preparation method comprises the steps as follows: the nano porous copper is prepared by a dealloying method; then nano porous copper and manganese dioxide mixed powder is prepared; finally, dried nano porous copper and manganese dioxide mixed powder is mixed with binder polytetrafluoroethylene according to the mass ratio of 95 to 5, anhydrous ethyl alcohol is taken as a dispersing agent and ground for 10 min in an agate mortar to mix to be pasty, and then evenly coated on a nickel screen with the dimension of 30 mm* 10 mm, the electrode plate is formed by the pressing of the powder tablet machine under the pressure of 10 MPa, and then drying is performed until constant weight is obtained, so that the electrode plate for the super capacitor is prepared. The defects of complex process, high energy consumption and high manufacturing cost in the manganese dioxide electrode material preparation method in the prior art can be overcome.

The invention discloses a three-dimensional porous stent. The three-dimensional porous stent is made from composite biomaterials consists of degradable natural biomaterials and degradable artificiallysynthesized macromolecule materials. The three-dimensional porous stent has a three-dimensional orderly porous structure in which holes are homogeneous, mutually penetrated and regular in distribution, and the hole diameter is 80-350[mu]m. The invention further discloses a preparation method and application of the three-dimensional porous stent. According to the method disclosed by the invention,the advantages of an emulsion microflow control technique and the advantages of the composite biomaterials are combined. The three-dimensional porous stent disclosed by the invention has favorable biocompatibility and biodegradability and has the characteristics that the hole diameter is appropriate, the holes are mutually penetrated, and the three-dimensional porous stent is degradable and compressible, can be shaped and can be used for performing drainage effectively, and good space is provided for medicine delivery and slow release, cell growth and metabolism and tissue repair; the proportion of ingredients of the compound materials and the holes in concentrated distribution can guarantee that the three-dimensional porous stent has favorable compression and resilience properties like sponge, so that the three-dimensional porous stent can better adapt to the shape of the uterine cavity or the shape of other positions needing prevention of adhesion, and the effect of effectively preventing the adhesion can be achieved.

The invention discloses a method for preparing a porous polymer microneedle based on a phase separation technology and application of the method. The method comprises the following steps that 1, a polymer is dissolved into a solvent A to obtain a polymer solution; 2, the polymer solution is put into a microneedle mould; 3, the microneedle mould is placed in a poor solvent B, so that phase separation of the polymer in the microneedle mould is facilitated; 4, the poor solvent B is removed, and then the porous polymer microneedle can be obtained. Through the simple and mild phase separation technology, the porous polymer microneedles can be prepared on a large scale, and therefore, the technical problems can be solved that the preparation process of the porous polymer microneedle is complicated, the conditions are harsh, the technology is tedious, the price is high, the pore structure, the size and the distribution are difficult to control, and it is difficult for large-scale production and application. The prepared porous polymer microneedle can be used for interstitial fluid extraction and transdermal drug delivery.

The invention relates to a porous silicon material and a preparation method thereof. The method for preparing the porous silicon material comprises the following steps: carrying out an in-situ catalytic reaction between a silicon material and chloromethane at the temperature of 401 to 800 DEG C in the presence of a solid copper-based catalyst, and preparing the porous silicon material through calcining, acid pickling, alkaline washing and other after-treatment impurity removal technologies, wherein the solid copper-based catalyst comprises one or a mixture of more than two in primary catalysts such as CuOx, CuCl and CuCl2, x is more than or equal to 0 and less than or equal to 1, as well as a small amount of secondary catalysts. Reaction condition parameters are regulated, so that the pore size, pore size distribution and porosity of the silicon material can be regulated. According to the method, a porous silicon material which is difficultly obtained in the patented technology at present is obtained, and important organic silicon monomer chemicals can be obtained. The porous silicon material prepared by the method is uniform in pore size, low in production cost, simple in process and suitable for industrial production and has wide application prospects.

The invention relates to a preparation method of silicon nitride, silicon carbide and tantalum carbide combined foam ceramic. The preparation method is characterized by comprising the following steps: uniformly mixing TaC, silicon micropowder and phenolic resin in addition to a hydroxypropyl methyl cellulose solution to prepare ceramic slurry; then, impregnating the ceramic slurry on polyurethane foam; and drying and firing in a nitrogen polyurethane to prepare the silicon nitride, silicon carbide and tantalum carbide combined foam ceramic. The silicon nitride, silicon carbide and tantalum carbide combined foam ceramic prepared by the invention is uniform in micro-structure, high in strength and uniform in pore size, and carbon and residue of free silicon are avoided, so that the strength, high-temperature resistance and hot impact resistance are greatly improved.

The invention discloses a preparation method of a silicon nitride and silicon carbide combined lanthanum hexaboride foamed ceramic. The preparation method is characterized by comprising the following steps: uniformly mixing LaB6, silica powder, phenolic resin and hydroxypropyl methyl cellulose solution to prepare ceramic slurry, soaking the ceramic slurry in a polyurethane foam, drying and sintering in nitrogen atmosphere to prepare the silicon nitride and silicon carbide combined lanthanum hexaboride foamed ceramic. The prepared silicon nitride and silicon carbide combined lanthanum hexaboride foamed ceramic has a uniform microscopic structure, high strength and uniform hole size, and is capable of avoiding the residue of carbon and free silicon so as to greatly improve the strength, the high temperature resistance and the thermal shock resistance.

The invention discloses a perforating device for plastic films. The perforating device comprise a device body and is characterized in that device legs are arranged on two sides of the bottom of the device body, driven rollers are arranged inside the device body through rotary shafts, each driven roller is connected with a drive roller through a conveying belt, a roller motor is arranged on one side of each drive roller, a feed disc and a discharge disc are arranged in the middle of the top of the device body, a back plate is arranged at the back of the device body, a power switch is arranged in the middle of the top of the back plate, spindle motors are arranged inside the back plate, and the outer surface of the back plate is provided with rotary spindles. The perforating device has the advantages that the perforating device adopting mechanical perforating is simple to operate, perforating speed can be increased by utilizing double-side perforating, the size of perforated holes is unchanged, uniform hole size is achieved, regular and rhythmed perforating can be achieved through the mechanical performance, hole intervals are identical, and perforating efficiency is increased.

The invention discloses an automatic digging mechanism of an intelligent construction tunneling machine. The automatic digging mechanism comprises a first tunneling mechanism and a second tunneling mechanism, wherein the first tunneling mechanism is arranged on the second tunneling mechanism, a ring of synchronously telescopic and rotating first drill bits are arranged on the first tunneling mechanism, a first top pressing shaft is arranged at an end of each first drill bit, a first chain wheel is arranged at the end of each first top pressing shaft, a ring of synchronously telescopic and rotating second drill bits are arranged on the second tunneling mechanism, a fourth top pressing shaft is arranged at the end of each second drill bit, and a second chain disc is arranged at the end of each fourth top pressing shaft. The first drill bits and the second drill bits drill holes on a wall, so that the hole size on the wall can be unified, the problem of different hole sizes caused by manual drilling can be avoided, and the digging efficiency is improved greatly.

The invention discloses a nonvolatile resistive random access memory with an adjustable write-in voltage and a preparation method thereof, and belongs to the field of resistive random access memory devices. The memory device includes a substrate, a bottom electrode, a resistive function layer, and a top electrode. and the resistive function layer is an organic polymer film which is prepared by spin-coating a mixed solution of two polymers and contains nano-pores on the surface. By changing the spin-coating conditions of the mixed solution, the sizes of the thin film holes can be adjusted, andthen the accurate regulation and control of the device write-in voltage are achieved. The memory device provided by the invention is simple in structure and is easy to process, shows nonvolatile storage characteristics, can realize the accurate regulation and control on the write-in voltage, and has a wide application prospect in the field of information storage.

The invention discloses a foam-like magnetic chitosan adsorbent and a preparation method thereof. The foam adsorbent is foamed by carbon dioxide produced by the reaction of sodium bicarbonate and acetic acid, and is prepared under the aid and protection of glycerol, the size and distribution of pores in the foam adsorbent are uniform, and more active groups are retained on chitosan. Consequently,the foam-like magnetic chitosan adsorbent has the advantages of having adsorbability to metal ions, and being conducive to large-scale application of the foamed chitosan-based adsorbent in water treatment.

The invention discloses a preparation method of silicon nitride and silicon carbide combined niobium carbide foamed ceramic. The preparation method is characterized by comprising the steps of uniformly mixing NbC, silica micro-powder, phenolic resin and a hydroxypropyl methyl cellulose solution to form ceramic slurry, immersing polyurethane foam in the ceramic slurry, drying, and firing in an nitrogen atmosphere to obtain the silicon nitride and silicon carbide combined niobium carbide foamed ceramic. The silicon nitride and silicon carbide combined niobium carbide foamed ceramic has a uniform microscopic structure, is high in strength and uniform in pore size and is free of residue of carbon and free silicon, and the strength, high-temperature resistance and thermal shock resistance of the foamed ceramic are improved substantially.

The invention provides an active NS-GAM gene scaffold for treating scalds. According to the active gene scaffold, a crosslinked scaffold of carboxymethyl chitosan and sodium alginate carries an arginine-chitosan gene vector and the arginine-chitosan gene vector enwraps a target gene. The prepared NS-GAM has an obvious wound repairing effect on scalded skin of a rat, has relatively mild inflammatory reaction, can promote wound repairing by achieving effective in-vivo transfection, has a very significant function of promoting repairing of the skin suffering from deep second-degree scald, and cangenerate a relatively ideal benign repairing effect.

The invention discloses a preparation method of silicon nitride, silicon carbide and molybdenum carbide combined foam ceramic. The preparation method is characterized by comprising the steps of uniformly mixing Mo2C, silica powder, phenolic resin and a hydroxypropyl methyl cellulose solution to prepare ceramic slurry; then, dipping the ceramic slurry on polyurethane foam, and drying; and next, firing at the nitrogen atmosphere to prepare the silicon nitride, silicon carbide and molybdenum carbide combined foam ceramic. The silicon nitride, silicon carbide and molybdenum carbide combined foam ceramic prepared by using the preparation method disclosed by the invention is uniform in microstructure, high in strength and uniform in pore size, and the residues of carbon and free silicon are avoided, so that the strength, high temperature resistance and thermal shock resistance of the silicon nitride, silicon carbide and molybdenum carbide combined foam ceramic are greatly improved.