9 results about "Oxidation-reduction process" patented technology

The application provides a preparation method of gold powder for matching low-temperature co-fired ceramic, and submicron irregular gold powder is prepared in an aqueous solution of chloroauric acid through an oxidation-reduction method. In the preparation process, amino acid is used as a gold ion complexing agent and a pH buffer of a reaction solution, a small-molecule organic substance containing an imidazole functional group and having weak reduction is used as a reducing agent, and after the gold powder is washed with deionized water, ethanol is used to replace water in the powder, and the like, so that submicron irregular gold powder which is not agglomerated is prepared. The gold powder prepared by the application has a particle size range of 200nm-900nm, has good dispersibility in alcohol and ester solvents, and after sintering, a film layer is dense, can be matched with various green ceramic materials at home and abroad, and after sintering, a substrate is flat and has a warping degree less than 0.1mm. The preparation method of the application has high yield and is convenient in the preparation process.

The application discloses a kind of synthesis methods of high-purity electronic grade sodium hypophosphite, dilute phosphine gas is passed into to the mixed solution of sodium hypochlorite and sodium hydroxide that has been pre-cooled with sufficient stirring, and sodium hydroxide is added to carry out reaction;After reaction is completed, filtration, concentration, crystallization, separation are carried out, and the obtained product is purified by resin to obtain high-purity electronic grade sodium hypophosphite product.Compared with the traditional "yellow phosphorus-lime-soda" oxidation-reduction method for preparing industrial grade product and then preparing high-purity electronic grade sodium hypophosphite, the product purification difficulty of the application is low, by using 7N grade ultra-high purity phosphine without any metal impurities, the problem that arsenic, silicon, germanium, nickel, chromium and other metal impurities cannot be completely removed by traditional process can be effectively solved.In addition, the application also has the advantages of effectively solving the problem of three wastes, high recycling rate of by-products, high economy and the like.

The invention discloses a method for preparing schizophyllum commune polysaccharide through high-pressure homogenization and application of the schizophyllum commune polysaccharide, and belongs to the technical field of food and medical treatment. On the basis of a traditional water extraction and alcohol precipitation process, the molecular weight and viscosity of schizophyllum commune fermentation liquor polysaccharide are remarkably reduced through a high-pressure homogenization technology, the schizophyllum commune fermentation liquor polysaccharide is smoother in morphology, and meanwhile a triple-helix structure is maintained; the physical properties of the polysaccharide treated by the method are optimized, and the immunoregulation, anti-apoptosis and anti-oxidative damage activity are also remarkably enhanced. Furthermore, the polysaccharide-selenium nanoparticle compound is prepared from the polysaccharide, sodium selenite and L-ascorbic acid through a mild one-step oxidation-reduction method, the water solubility, biocompatibility and bioavailability of the polysaccharide can be effectively improved through the compound, and the polysaccharide-selenium nanoparticle compound shows more excellent apoptosis resistance and oxidation resistance in a model experiment.

The invention discloses a preparation method of a Co porphyrin / graphene interlayer confinement catalyst, and belongs to the field of preparation of organic nano materials. The method comprises the following steps: firstly synthesizing free porphyrin (such as HTPP) through metallization reaction, and then reacting with cobalt salt to insert cobalt ions to synthesize Co porphyrin. The layered graphene is synthesized by using an efficient and mild oxidation-reduction method. And finally, limiting Co porphyrin molecules between graphene layers by utilizing pi-pi accumulation and electrostatic interaction to form the domain-limited catalyst with a layered structure. The preparation method has the characteristics that a good layered structure can promote reactant enrichment and directional conversion of an intermediate, the stability of a Co active center is enhanced by utilizing a confinement effect, an electron transmission path (from graphene to Co porphyrin) is optimized, the catalytic activity of the catalyst is improved, and the application potential is relatively large.

The application discloses a kind of redox processes for realizing the efficient recovery of chromium complex in Cr (III) -EDTA-containing wastewater, first, appropriate sodium percarbonate, formic acid is added to Cr (III) -EDTA-containing wastewater containing heavy metal chromium, and stirring is dissolved;Immediately, ozone is introduced into the mixed solution, and the oxidation of active species hydroxyl radical and carbonate radical, the reduction of active species carbon dioxide radical is generated by ozone / sodium percarbonate / formic acid advanced oxidation reduction method, which realizes the rapid complex breaking of chromium complex in wastewater, the reduction of hexavalent chromium, and the rapid removal of chromium ions in wastewater;At the same time, the organic ligand EDTA in wastewater is rapidly mineralized and decomposed under the oxidation of highly active free radicals.The application can realize the efficient complex breaking of chromium complex in Cr (III) -EDTA-containing wastewater and the synchronous removal of heavy metal chromium, and the heavy metal chromium is recycled, which has the advantages of economic efficiency, simple operation, easy engineering application, etc.

The invention discloses a reaction furnace capable of observing the change of a reaction column for element isotope analysis, which is mainly used for visualization and quantification of an oxidation-reduction process in an element-stable isotope ratio mass spectrometer and comprises a reaction furnace body, a reaction tube and an observation strip, the reaction tube is arranged in the reaction furnace body, an opening is formed in the surface of the reaction tube, a through hole is formed in the surface of the reaction furnace body, the observation strip is arranged between the through hole and the opening, the observation strip covers the through hole and the opening in a sealing manner, and the observation strip is made of a transparent material. By adopting the arrangement, the oxidation reduction process can be observed and quantified at any time during use, and the visualization and quantification of the ash content volume and the reduced copper residual degree are realized.

The application discloses a method for rapidly preparing a high-sensitivity three-dimensional circular hole aerogel stress sensor and belongs to the technical field of porous carbon materials. The method comprises the following steps: (1) graphite powder is subjected to an oxidation-reduction method to obtain graphene oxide (GO) with a large specific surface area and good dispersibility; and MAX is etched by hydrochloric acid to obtain a carbon titanium carbide (MXene) suspension with excellent conductive performance; (2) GO, MXene, ascorbic acid and a foaming agent are mixed and then subjected to a hydrothermal reaction to obtain a composite hydrogel; (3) the composite hydrogel is subjected to freezing, freezing and thawing in ethanol and then air drying, and is subjected to carbonization by a Joule heating device to obtain a composite carbon aerogel with good mechanical properties; and (4) the composite aerogel is attached to a graphite foil electrode to assemble a stress sensor. The method is simple and has the potential of rapidly preparing a high-sensitivity aerogel stress sensor; the prepared aerogel has high compressibility and super-high sensitivity, and is expected to be used as a matching device for modern intelligent equipment.

The invention provides a preparation method of an ultra-fine grain ODS-Cu composite material for synergistically improving mechanical-electrical conductivity, and relates to the technical field of copper-based composite materials and preparation. The method comprises the following steps: preparing superfine ODS-Cu powder containing 0.5-1.5 wt% of Al2O3 by adopting an in-situ endogenous oxidation-reduction method, carrying out cold isostatic pressing, sintering under a hydrogen protection atmosphere, carrying out hot extrusion and annealing to obtain a densified ODS-Cu formed blank, and drawing or rolling to obtain an intermediate plate; carrying out low-temperature annealing on the intermediate plate and then transferring the intermediate plate into liquid nitrogen until the core temperature of the plate is less than or equal to-150 DEG C; and the obtained plate is subjected to multi-pass cold rolling treatment, and the composite material is obtained. Compared with similar copper-based dispersion strengthening or severe plastic deformation routes in the prior art, the tensile strength and the yield strength can be improved by more than 10%, the ductility can be improved by more than 50%, the electric conductivity is higher than 75% IACS, and the softening temperature is higher than 900 DEG C.

The invention provides a ferroelectric-polyacid coupled long-memory composite electrochromic film as well as a preparation method and application thereof, and belongs to the technical field of electrochromic materials and devices. The thin film is composed of FTO conductive glass, a TiO2 porous framework layer, a P2W17V polyacid layer deposited in the framework and a P (VDF-TrFE) ferroelectric functional layer, and a built-in electric field generated by polarization of the ferroelectric layer is deeply coupled with a polyacid oxidation reduction process, so that charges are effectively locked, ion diffusion is inhibited, and the limitation of traditional physical lamination is broken. The optical memory time of the prepared film is prolonged from 489.8 s to 2357.2 s, the bistable performance is remarkably enhanced, and the technological process is simple.