46results about How to "High reproducibility of preparation" patented technology

The invention discloses a method for growing large-area graphene on an insulating substrate. According to the method, a growing substrate is taken as an insulating material, a copper foil is taken as a catalyst and a carbon source, nitrogen and protective gas are taken as source gases, and the large-area graphene is grown on the insulating substrate by adopting a two-step (low-pressure growth and high-pressure growth) chemical vapor deposition method and using the short-range catalytic effect of the copper coil through face-to-face contact of the insulating substrate and the copper foil. The method disclosed by the invention is simple in operation of the whole process and low in cost; and the sample preparation is very high in repeatability and is less interfered by external world. The prepared single-layer graphene can be made into a large-area circuit device by using an exposure method without needing a complex transfer technology.

The single crystal silicon ingot and wafer of one embodiment has a transition region formed therein which predominantly has crystal defects of 10 nm to 30 nm in size from among crystal defects included in at least one region of a vacancy predominant non-defective region and an interstitial predominant non-defective region.

The invention relates to a rapid preparation method of a monoclinic phase VO2 metal-insulator phase transformation ceramic material. The method comprises the following steps: reducing V2O5 with citric acid by a hydrothermal method, carrying out centrifugal cleaning to obtain an orthorhombic phase VO2 nanopowder, carrying out high-temperature heat treatment to obtain a monoclinic phase VO2 powder, and finally compressing and sintering to obtain the monoclinic phase VO2 metal-insulator phase transformation ceramic. The process is simple; preparation efficiency is high; sintering temperature is low; energy consumption is low; cost is low; the method is environment friendly, nontoxic and pollution-free; and the prepared ceramic has good phase transformation property and stable and uniform structure.

The invention provides a 3D-TSV (Through Silicon Via) in-situ tension test sample and a preparation method thereof. The test sample comprises a test sample column part, fixing parts and clamping parts, wherein a test sample column is prepared from a dry film as a substitute for positive photoresist, so as to be convenient for growth of a metal column; the fixing parts are electroplated together with the test sample column part and respectively serve as a port for connecting the test sample column part with external, so that the problem that the test sample column is difficult to operate due to small size is solved. In order to facilitate the clamping operation of a test instrument, the clamping parts are prepared via an electroplating, adhesion or welding process; according to the electroplating process, a layer of strip-shaped metal is directly shaped in each a fixing end, the two ends of each strip-shaped metal are provided with rings and each metal is folded to align the rings so as to obtain one clamping part; according to the adhesion or welding process, each clamping part is directly connected with one fixing end by adhesion or welding. In design, the test sample and the method are convenient to operate in whole, the steps are simple and the technology is optimized on the basis of ensuring the accuracy.

The invention discloses a photo-thermal catalytic hydrogenation catalyst as well as preparation and application thereof to selective hydrogenation reaction of p-benzoquinone. The photo-thermal catalytic hydrogenation catalyst is prepared from a mesoporous carbon microsphere carrier, and carbon quantum dots and metal quantum dots which are loaded on the surface of the carrier; the size of the catalyst is 50 to 100nm; the grain diameter range of the carbon quantum dots is 7 to 9.5nm; the metal quantum dots are one or a combination of two of palladium quantum dots and platinum quantum dots; the grain diameter range of the metal quantum dots is 10 to 15nm; in the catalyst, the mass percent of the carbon quantum dots and the metal quantum dots is 10 to 30 percent and 1 to 2 percent respectively. The photo-thermal catalytic hydrogenation catalyst provided by the invention is applied to reaction of selectively carrying out catalytic hydrogenation on the p-benzoquinone under the irradiation ofultraviolet light with the wavelength of 350 to 400nm to synthesize hydroquinone, and has the characteristics of high conversion rate, good selectivity, rapid hydrogenation reaction speed and good stability.

The invention relates to a preparation method of a catalyst for butylene oxidative dehydrogenation to produce butadiene, and mainly solves the problems of easy loss of components in precipitation process and poor reproducibility in the existing preparation of the catalyst. The invention adopts ball milling method to grind iron oxide, magnesium oxide, zinc oxide and a catalytic promoter in the form of oxides into powder, so as to obtain a mixture of complex metal oxides, the mixture is subjected to high-temperature calcination to obtain butylene, and butylene is subjected to oxidative dehydrogenation to obtain butadiene. The technical scheme well solves the problem, and can be used in industrial production of butadiene from butylene oxidative dehydrogenation.

Bipolar transistors and methods for fabricating bipolar transistors are disclosed wherein an emitter-base dielectric stack is formed between emitter and base structures, comprising a carbide layer situated between first and second oxide layers. The carbide layer provides an etch stop for etching the overlying oxide layer, and the underlying oxide layer provides an etch stop for etching the carbide layer to form an emitter-base contact opening.

The invention discloses a photo-thermal catalytic hydrogenation catalyst as well as preparation and application thereof to selective hydrogenation reaction of 3,4-dichloronitrobenzene. The photo-thermal catalytic hydrogenation catalyst is prepared from a mesoporous carbon microsphere carrier, and carbon quantum dots and metal quantum dots which are loaded on the surface of the carrier; the size ofthe catalyst is 50 to 100nm; the grain diameter range of the carbon quantum dots is 4.5 to 6.5nm; the metal quantum dots are one or a combination of two of palladium quantum dots and platinum quantumdots; the grain diameter range of the metal quantum dots is 10 to 15nm; in the catalyst, the mass percent of the carbon quantum dots and the metal quantum dots is 10 to 30 percent and 1 to 2 percentrespectively. The photo-thermal catalytic hydrogenation catalyst provided by the invention is applied to reaction of selectively carrying out catalytic hydrogenation on the 3,4-dichloronitrobenzene under the irradiation of ultraviolet light with the wavelength of 280 to 350nm to synthesize 3,4-dichloroaniline, and has the characteristics of high conversion rate, good selectivity, rapid hydrogenation reaction speed and good stability.

The invention discloses a copper nanoparticle cluster loaded electrochemical sensor and a preparation method thereof. The sensor mainly comprises a glassy carbon electrode, an SPAEK-6F-BI (sulfonated polyaryletherketone-6F-benzimidazole) polymer thin-layer template precursor and carrier film adopting a hexafluorobisphenol A and benzimidazole structure and a copper nanoparticle cluster loaded high-electrocatalytic-activity film. The electrochemical sensor provided with a copper nano particle cluster modified electrode and prepared with the method having all mentioned advantages and effects has a remarkably enhanced electro-catalytic reduction effect on H2O2, and the sensor manufacturing repeatability is high; when the electrochemical sensor is used for H2O2 electrochemical analysis, the response sensitivity is high, the test stability and repeatability are good, and the electrochemical sensor can be used for quickly and accurately analyzing the content of low-concentration H2O2.

A pulse modulator includes a circulator which comprises: two ferrite plates; a plurality of mode suppressors for transmitting therethrough an LSM mode electromagnetic wave while shutting off an LSE mode electromagnetic wave; and an impedance matching member mounted on one end face of each of the mode suppressors, wherein a pulse modulation switch having a Schottky barrier diode is mounted on the other end face of any one of the mode suppressors in such a manner that the direction of application of a bias voltage to the Schottky barrier diode coincides with the direction of electric field of the LSM mode electromagnetic wave, and wherein the distance from an edge of the ferrite plates to the Schottky barrier diode is set approximately equal to nλ/2. Herein, n is an integer not smaller than 1, and λ is the wavelength of the high frequency signal.

The invention discloses external nano-hydroxyapatite/polydopamine wet adhesion type styptic powder and a preparation method thereof. The styptic powder is nano-hydroxyapatite loaded with polydopamine.The preparation method comprises the following steps: adding nano-hydroxyapatite and dopamine into a weakly alkaline solution, and reacting at room temperature; and carrying out freeze drying on theproduct to obtain the nano-hydroxyapatite/polydopamine needle-like composite styptic powder. The material has a multifunctional hydroxyapatite and polydopamine structure, and can be further modified with many substrates. The material can be applied to hemostasis in different forms in different dosage forms, can be prepared into emergency lifesaving powder, hemostasis hydrogel, self-adhesive dressing, hemostasis antibacterial sponge and the like by being integrated with other medical materials and medical instruments, and the novel drug delivery carrier can be prepared by doping or crosslinkingantibacterial, wound healing promoting and pain relieving drugs and nano-hydroxyapatite or reacting the drugs with polydopamine, and multifunctional integration of the hemostatic material is realized.

The invention discloses a wide-spectrum extremely-low transmission structure and a preparation method thereof. The wide-spectrum extremely-low transmission structure comprises a substrate, and furthercomprises a nano forest structure directly formed on at least one surface of the substrate, and metal nano particles loaded on the nano forest structure; when only one surface of the substrate is ofa nano forest structure, a metal layer is arranged on the other surface, opposite to the nano forest structure, of the substrate. The structure provided by the invention has the advantages of high stability and high light absorption capability.

The invention discloses a method for regulating and controlling interaction between metal nanoparticles and a carrier by plasma, which comprises the following steps: S1, loading a metal precursor on the carrier by adopting an impregnation method or a deposition-precipitation method, and cleaning and drying to obtain a catalyst; s2, putting the obtained catalyst into a plasma generating device, andpretreating the catalyst by adopting plasma in a reducing atmosphere; s3, in an oxidizing atmosphere, activating the catalyst by adopting plasma; and S4, after activation treatment, treating the catalyst by adopting plasma in a reducing atmosphere to obtain the supported metal catalyst. According to the method disclosed by the invention, the supported catalyst is pretreated, activated and retreated in sequence by utilizing plasmas generated by discharging in different atmospheres, so that the interaction between the metal nanoparticles and the carrier is effectively modulated, and the stability of the nano-catalyst is remarkably enhanced while the sizes of the metal nanoparticles are controlled.

The invention discloses a magnesium-doped cobalt disulfide composite carbon nanotube material, a preparation method and application of the magnesium-doped cobalt disulfide composite carbon nanotube material in preparation of a zinc-air battery cathode catalyst. According to the preparation method, a zinc-air battery cathode catalyst with oxygen reduction and oxygen evolution reactions is preparedby adopting a hydrothermal method, namely magnesium nitrate is used as a doping agent, cobalt acetate is used as a cobalt-based metal sulfide raw material, sulfur powder is used as a vulcanizing agent, and the metal sulfide and carbon nanotubes are compounded at a high temperature in an inert atmosphere. According to the method, under the combination effect of metals and the carbon material, on the one hand, agglomeration of cobalt can be effectively inhibited, on the other hand, oxygen holes with efficient catalytic oxygen reduction and cobalt disulfide particles with oxygen evolution activity are synchronously generated on the carbon nanotubes, and the finally obtained catalyst material can be used for zinc-air batteries to realize long-time and high-stability charge-discharge circulation.

The invention relates to the technical field of microporous membrane materials, and discloses a microporous membrane material preparation method, a microporous membrane material and application thereof. The method comprises the steps of (1) forming a non-conductive microarray on an electrode and using the non-conductive microarray as a mold plate; (2) placing the mold plate in electrolyte for electrodeposition, and forming a film-like deposition layer on an area, without the microarray, on the electrode; and (3) stripping the film-like deposition layer. The method is high in efficiency, simpleand controllable in large area; the membrane material with a special complicated pore structure and the adjustable size and shape can be prepared; the advantages that the edges of pores are neat, thepreparation repeatability is high, the mechanical and electrical properties are stable, and the relative density is low are achieved, the preparation method is wide in application face, and the microporous membrane material prepared by the method can be used in the fields of lithium ion batteries, oil-water separation, chemical biosensors, solar cells and supercapacitors.

The invention provides a graphene oxide-based nano composite material for amino acid enantiomer separation analysis and a preparation method thereof. The method comprises the steps of: dispersing an L-amino acid derivative gelator into a metal ion solution, and heating and cooling to obtain composite hydrogel; dropwise adding a graphene oxide solution into the composite hydrogel, oscillating and uniformly mixing, and standing for layering at room temperature;and performing filtration to obtain products. The method provided by the invention solves the problems of low separation efficiency, complex operation, difficult recycling and low repeatable utilization rate in the existing enantiomer separation process. The composite material disclosed by the invention can realize chiral conversion under the regulation and control of metal ions, and adsorption of different types of amino acid enantiomers is realized according to different chiral structures, so that effective separation is realized. The solid composite material is easy to recycle, can be repeatedly used, is convenient to operate and has practical application value. The preparation method of the material does not need complex synthesis steps, and is suitable for commercial application of enantiomer chiral separation analysis.

The invention discloses a photo-thermal catalytic hydrogenation catalyst as well as a preparation method and application thereof. The photo-thermal catalytic hydrogenation catalyst is prepared from amesoporous carbon microsphere carrier, and carbon quantum dots and metal quantum dots which are loaded on the surface of the carrier; the size of the catalyst is 50 to 100nm; the grain diameter rangeof the carbon quantum dots is 1 to 4nm; the metal quantum dots are one or a combination of two of palladium quantum dots and platinum quantum dots; the grain diameter range of the metal quantum dots is 10 to 15nm; in the catalyst, the mass percent of the carbon quantum dots and the metal quantum dots is 10 to 30 percent and 1 to 2 percent respectively. The photo-thermal catalytic hydrogenation catalyst provided by the invention is applied to reaction of selectively carrying out catalytic hydrogenation on hydroquinone under the irradiation of ultraviolet light with the wavelength of 200 to 280nm to synthesize 1,4-cyclohexanediol, and has the characteristics of high conversion rate, good selectivity and good stability.

The invention belongs to the field of alloy catalysts, and particularly discloses a self-optimizating alloy catalyst and a preparation method and application thereof. The preparation method comprisesthe following steps that (1) Ag elementary substance, Cu elementary substance and Al elementary substance are subjected to vacuum melting, AgXCuYAlZ alloy is prepared, wherein X+Y+Z = 100 and the ratio of X to Y to Z is (15-30):(0.1-1):(69-84.9); (2) the alloy is subjected to melt-spinning to preapre an alloy strip; (3) the aluminum is removed from the alloy strip by using acid to obtain an initial catalyst; (4) electrochemical treatment then is carried out on the initial-state catalyst to segregate Cu on the Ag surface, thereby obtaining the catalyst. The alloy catalyst prepared by the invention is a catalytic material with a self-optimizing function, is stable in catalytic performance, is high in current density and catalytic efficiency after being optimized, is suitable for mass production, and is beneficial to industrial application.

The invention discloses a photoelectrochemical sensor preparation method based on efficient and stable in-situ growth of a titanium dioxide/nanogold photo-anode. The preparation method comprises the following steps: cleaning ITO (indium tin oxide) slices of an indium tin oxide electrode; sequentially putting the ITO slices into acetone, ethanol and an ultrapure water solution for ultrasonic treatment; wiping with an ethanol cotton ball, washing with ultrapure water, annealing in a culture dish with one side of ITO upward, taking out the ITO slices, and carrying out plasma and ozone treatment;spin-coating a tetraisopropyl titanate, butyl titanate or ethyl titanate precursor on the treated ITO slices, and then annealing a spin-coated ITO substrate to obtain an ITO/TiO2 electrode; and cooling the ITO/TiO2 electrode to room temperature, and carrying out in-situ gold nanoparticle loading to obtain an ITO/TiO2/Au NPs photo-anode. The photoelectrochemical sensor has the advantages of being efficient, uniform, stable, high in preparation repeatability, simple in structure, good in storage stability, good in detection repeatability, sensitive to miRNA-21, specific to miRNA-21 and the like,and is used for detecting miRNA.