3results about How to "Components are easy to control" patented technology

The application discloses a preparation method of a transition metal oxide and / or transition metal sulfide / carbon cloth composite wave-absorbing material, and belongs to the technical field of wave-absorbing materials. The method comprises the following steps: dissolving metal salt and sodium citrate in a mixed solvent to obtain a mixed solution; immersing hydrophilic carbon cloth treated by acid in the mixed solution, and then moving to a hydrothermal kettle for heat preservation treatment to obtain a transition metal oxide / carbon cloth; dissolving a sulfur-containing compound in an alcohol solution, immersing the transition metal oxide / carbon cloth in the alcohol solution containing the sulfur-containing compound, and then moving to the hydrothermal kettle for heat preservation treatment; adjusting the temperature and time of the heat preservation treatment to control the content of sulfide in the product, and finally obtaining a transition metal oxide / sulfide / carbon cloth or a transition metal sulfide / carbon cloth. The application further discloses the obtained transition metal oxide and / or transition metal sulfide / carbon cloth composite wave-absorbing material. The method is simple, the micro-morphology and components of the obtained material are controllable, the material has excellent wave-absorbing performance, and has a wide application prospect.

A lithium-mediated electrochemical method for ammonia synthesis, relating to the field of ammonia synthesis technology, solves the technical problems of severe side reactions, limited nitrogen mass transfer, and poor interfacial stability in existing lithium-mediated ammonia synthesis systems. Tetra(4-formylphenyl)porphyrin iron and an amino-containing multifunctional organic ligand are added to a mixed solvent of n-butanol and o-dichlorobenzene. An acid catalyst is added, and after stirring until homogeneous, the mixture is degassed and sealed for reaction. The solid product is collected by centrifugation, washed, and dried to obtain COF powder. This powder is then added to an ethanol-water solution, followed by ultrasonic dispersion with Nafion solution. The powder is then drop-coated / sprayed onto the surface of a carbon paper current collector and dried. This powder is used as the working electrode, with a platinum mesh as the counter electrode, a platinum wire as the quasi-reference electrode, and a LiBF4 tetrahydrofuran solution as the electrolyte. Ethanol is used as the proton donor, and electrolysis is performed under a nitrogen atmosphere using a constant current. This invention can be applied to the field of ammonia synthesis technology.

This invention belongs to the field of metallic materials technology, specifically a TiZrMo-based refractory high-entropy alloy and its preparation method. The refractory high-entropy alloy is composed of any two of Al, Cr, and Nb, and Ti, Zr, and Mo. The atomic radius difference δ of the refractory high-entropy alloy is ≤6.6%, the alloy entropy enthalpy ratio Ω is ≥1.1, and the mixing enthalpy ΔH is... mix The energy density ranges from -18.0 to 4.0 kJ / mol, and the vacancy electron concentration (VEC) is <6.87. Furthermore, the preparation method of this invention has the advantages of simple steps, easily controllable composition, high production efficiency, and near-net-shape forming. The prepared refractory high-entropy alloy has a stable microstructure and a density of less than 7.00 g / cm³. 3 It has a Vickers hardness greater than 1400 HV, a room temperature compressive strength consistently above 980 MPa, an elongation at break greater than 10.8%, and an oxidation weight gain of less than 15.00 mg / cm³ at 800℃ for 12 hours. 2 It is low in cost and easy to apply on a large scale in industrial applications.