30results about How to "No need to restore" patented technology

The invention discloses a low-cost carbonaceous graphene sheet and a preparation method thereof. Carbonaceous materials (coal, coke, resin carbon, graphite, bamboo charcoal or activated carbon) are used as raw materials, mixed with additives, vacuum carbonized and pickled , ball milling and other processes to prepare graphene sheets at low cost. The graphene sheet prepared by the invention has few structural defects, low preparation cost, simple operation, environmental protection, easy industrialization, and has remarkable economic and social benefits.

The invention discloses a preparation method of Bi0.5Na0.5Cu3Ti4O12 giant dielectric non-linear pressure-sensitive ceramics, belonging to the field of the electronic information component material. In the preparation method, a sol-gel method for adopting citric acid and ethylene diamine tetraacetic acid as a complexing agent is used to prepare the Bi0.5Na0.5Cu3Ti4O12 ceramics. The ceramics prepared by the preparation method has large dielectric constant and high non-linear pressure-sensitive coefficient, and is a novel capacitive-pressure-sensitive bifunctional ceramic material with wide application prospect and the dielectric performance and the non-linear pressure-sensitive performance of the material can be regulated and controlled by changing the sintering temperature.

The invention discloses a method for preparing blue light fluorescent powder Sr by self-reduction 2 B 5 o 9 Cl:Eu 2+ method, the method will SrCl 2 ·6H 2 O, boron source and Eu 2 o 3 After grinding and mixing evenly, put it in a platinum crucible, seal it in a stainless steel flanged reaction kettle (use temperature less than 500°C, use pressure less than 49bar), put the reaction kettle in a muffle furnace, and react at 300-450°C. i.e. get Sr 2 B 5 o 9 Cl:Eu 2+ Phosphor powder, wherein the boron source is H 3 BO 3 or H 3 BO 3 and K 2 B 4 o 7 4H 2 O or Na 2 B 4 o 7 10H 2 O mixture. The method of the invention is simple, there are few types of reaction raw materials, no need to carry out under reducing atmosphere, the reaction efficiency is high, and the prepared Sr 2 B 5 o 9 Cl:Eu 2+ Phosphor powder has high purity, high quantum yield, and narrow emission spectrum. It is a potential blue light-emitting material and is suitable for industrial production.

The invention relates to a supported-coated noble metal catalyst and its preparation and application method. The catalyst provided by the invention has the characteristics of uniform particle size of precious metal particles, sintering resistance to high temperature water vapor atmosphere, and resistance to oxidation sintering. It is used in the steam reforming reaction process of pure methane or diluted methane, and has high reactivity, less carbon deposition, stable It has the advantages of good performance, no need to restore before reaction, and can be reused many times. The catalyst preparation method provided by the invention has good controllability, high repeatability, simple steps and low cost. The application method can flexibly and conveniently realize hydrogen production by reforming methane in a small and medium scale, and is an efficient on-line hydrogen production technology approach.

The invention discloses a Cr-doped Bi2Fe4O9 multiferroic ceramic material and a preparation method thereof. The preparation method comprises the step of carrying out high temperature annealing treatment by adopting a citric acid-nitrate sol gel self-propagating combustion reaction method to obtain the multiferroic ceramic material with a molecular formula of Bi2Fe4(4-x)Cr4xO9 (x is more than 0 and less than or equal to 0.08). The Cr-doped Bi2Fe4O9 multiferroic ceramic material has a single-phase structure, low leakage current and multiferroic property at room temperature and magnetic property and ferroelectricity of the material can be regulated by changing the doping content of Cr; and a preparation technology is simple, cost is low, no reducing atmosphere is required, and environmental protection, no toxicity and no pollution are achieved.

The invention relates to the field of materials of electronic information components, and discloses giant dielectric-nonlinear low-voltage varistor ceramic material and a preparation method thereof. The giant dielectric-nonlinear low-voltage varistor ceramic material of the invention is prepared by a sol-gel method in which a citric acid serves as a complexing agent, and has the molecular formula of Bi0.5-xNa0.5-xBa2xCu3Ti4O12, wherein x is more than 0 and less than or equal to 0.075. The ceramic material prepared by the method has a giant dielectric constant and nonlinear low-voltage varistor effect, is a multifunctional ceramic material with vast application prospect, and has dielectric properties and voltage-sensitive characteristics which are adjusted according to the ratio of Ba. The preparation method of the invention has the characteristics of simple process operation, short cycle, low cost, environmental friendliness, nontoxicity, no need of atmosphere reduction and the like.

The invention provides a gadolinium thulium vanadate / borate blue light-emitting material. The material is characterized in that the chemical formula is Gd1-y(VO4)x(BO3)1-x:Tmy; and in the formula, x is not less than 0.1 and not more than 0.9 and y is not less than 0.01 and not more than 0.05. In a preparation method of the material, ammonium metavanadate, gadolinium nitrate, thulium nitrate, boric acid and citric acid are selected as raw materials, and the preparation method comprises the following steps: (1) putting ammonium metavanadate and boric acid into a container, adding deionized water to form a solution defined as solution A, putting gadolinium nitrate, thulium nitrate and citric acid into the container, adding deionized water to form a solution defined as solution B, adding the solution A to the solution B, stirring the solution uniformly, thus forming sol, adjusting the pH value of the sol to be not less than 4 and not more than 10, continuing stirring at 60-80 DEG C until gel is formed and then drying the gel, thus obtaining a precursor; (2) grinding and dispersing the precursor, then roasting the product at normal pressure and 700-900 DEG C for 1-4 hours, then taking out the product and air-cooling the product; and (3) grinding and dispersing the roasted product, then washing the product and drying the washed powder.

The invention discloses a cobalt-base Fischer-Tropsch synthesis catalyst and a preparation method and application thereof. The catalyst comprises a mesoporous carbon carrier and an active component cobalt, wherein the active component cobalt is confined in the mesoporous carbon carrier. The catalyst has specific surface area of 220-400 m<2> / g and particle diameter of 50-150 um. The preparation method employs phenolic resin solution as an organic precursor, and then a sol-gel method is employed to embed the active component Co into the mesoporous carbon carrier. The catalyst prepared by the invention before usage only requires introduction of inert gas into at a certain temperature without hydrogen reduction, so as to obtain the catalyst containing cobalt. The catalyst of the invention has the advantages of high reduction degree, high dispersity, good stability, uniform size of active component, controllable carrier aperture and high selectivity on diesel, and can meet the requirements of a slurry bed reactor on the wear resistance of the catalyst.

The invention provides a niobate reversible photochromic material. The niobate reversible photochromic material has a general formula as shown in a formula I: Li1-xNbO3:xR; and in the formula I, R isa rare earth element, and x is more than or equal to 0 and less than or equal to 0.03. Compared with the prior art, the niobate reversible photochromic material provided by the invention has the following advantages: the color under the ultraviolet irradiation can slowly change to gray, and the color can restore the original color again after sunlight irradiation; furthermore, the material has high reversible photochromic fatigue resistance and can be widely applied to the fields of optical information storage, light regulation and control, optical devices, inductors, counterfeiting resistance, self-developing holographic recording photograph, radiation meters, protective packaging materials and the like. In addition, the invention provides a preparation method of the niobate reversible photochromic material. According to the method provided by the invention, the preparation raw materials are cheap, the preparation method is simple in process and high in repeatability, and the productis stable in properties.

The invention provides a graphene hollow fiber and a continuous preparation method thereof. The continuous preparation method of the graphene hollow fiber is characterized by comprising the following steps: continuously drawing copper wires out and immersing the drawn-out copper wires in a graphene oxide electrolyte; then, electrochemically plating graphene on the surfaces of the copper wires through a three-electrode system; next, continuously collecting the copper wires of which the surfaces are coated with the graphene, and rolling the collected copper wires into rolls; subsequently, immersing the rolls in an aqueous solution of ferric chloride to dissolve the copper wires; and finally, performing cleaning and drying so as to obtain the graphene hollow fiber. According to the graphene hollow fiber prepared by using the method, the hollow diameter and the thickness of a pipe wall can be adjusted and changed in a wide range, and a solid foundation for the applications of the graphene hollow fiber in the aspects of filtration and separation, energy, sensing, braking and the like is established.

The invention provides a graphene porous fiber and a continuous preparation method thereof. The continuous preparation method is characterized by including steps of continuously pulling a copper wire and immersing the copper wire in the graphene oxide electrolyte; then performing electrochemistry plating of graphene on the surface of the copper wire through a tri-electrode system; then continuously collecting the copper wire of which surface is coated with the graphene and rolling up; then immersing the copper wire to the ferric chloride solution to dissolve copper wire; at last, applying the surface tension force or external force to make the graphene contract, thus acquiring the graphene porous fiber. The graphene porous fiber prepared by the invention has big adjustment in terms of diameter, porosity and specific surface, and lays a solid foundation for the application of graphene porous fiber in terms of absorption, energy source, sensing and others.

The invention relates to a method for producing a gadolinium vanadate thulium blue luminescent material modified by glucose, and the method comprises the following steps: (1) taking ammonia metavanadate, gadolinium nitrate, thulium nitrate and citric acid as the basic raw materials, taking glucose as a modifier, putting ammonia metavanadate in a container and adding deionized water, defining the produced solution as a solution A, putting gadolinium nitrate, thulium nitrate and citric acid into the container and adding deionized water, defining the produced solution as a solution B, adding thesolution A into the solution B, then adding glucose and uniformly mixing to form sol, regulating the pH value of sol to: 4<=pH<=10, continuously stirring at the temperature of 60 DEG C - 80 DEG C until gel is formed, then drying the gel to obtain a precursor; (2) grinding and dispersing the precursor, calcinating at the normal pressure of 700 DEG C - 900 DEG C for 1 - 4 hours, then taking out andair cooling; (3) grinding and dispersing the calcinated products, then cleaning, drying the cleaned powder to obtain the gadolinium vanadate thulium blue luminescent material modified by glucose.

The invention discloses a method for preparing room-temperature multiferroic BiFeO3-SrTiO3 sosoloid ceramics, belonging to the technical field of information functional materials. The BiFeO3-SrTiO3 ceramics prepared by using the method have the advantages of single-phase structure, low drain current, room-temperature ferroelectric / ferromagnetic coexistence, and the like.