Patent classifications
C04B2235/425
Method for producing non-oxide ceramic powders
The invention relates to a method for producing a non-oxide ceramic powder comprising a nitride, a carbide, a boride or at least one MAX phase with the general composition Mn+1AXn, where M=at least one element from the group of transition elements (Sc, Ti, V, Cr, Zr, Nb, Mo, Hf and Ta), A=at least one A group element from the group (Si, Al, Ga, Ge, As, Cd, In, Sn, Tl and Pb), X=carbon (C) and/or nitrogen (N) and/or boron (B), and n=1, 2 or 3. According to the invention, corresponding quantities of elementary starting materials or other precursors are mixed with at least one metal halide salt (NZ), compressed (pellet), and heated for synthesis with a metal halide salt (NZ). The compressed pellet is first enveloped with another metal halide salt, compressed again, arranged in a salt bath and heated therewith until the melting temperature of the salt is exceeded. Optionally, melted silicate can be added, which prevents the salt from evaporating at high temperatures. Advantageously, the method can be carried out in the presence of air.
Polyimide-based composite carbon film with high thermal conductivity and preparation method therefor
The present invention discloses a polyimide-based composite carbon film with high thermal conductivity and a preparation method therefor. The preparation method includes: uniformly coating the surface of a polyimide-based carbon film with an aqueous graphene oxide solution, and then covering the same with another polyimide-based carbon film uniformly coated with an aqueous graphene oxide solution; repeating such operation; after the polyimide-based carbon films are dried, bonding the polyimide-based carbon films by means of graphene oxide so as to form a thick film; bonding the polyimide-based carbon films more tightly by means of further low-temperature hot pressing; and finally, obtaining a thick polyimide-based carbon film with high thermal conductivity by repairing defects by means of low-temperature heating pre-reduction and high-temperature and high-pressure thermal treatment. The thick polyimide-based carbon film with high thermal conductivity has a thickness greater than 100 μm and an in-plane thermal conductivity of even reaching 1700 W/mK or above.
CaO-ZrO2 Composition, Method for Producing CaO-ZrO2 Composition, and CaO-ZrO2-Containing Refractory Material and Casting Nozzle
Provided is a ZrO.sub.2—CaO—C based refractory material which is capable of maintaining high adhesion resistance over a long period of time, while exhibiting significant slaking resistance, and suppressing self-fluxing, i.e., exhibiting corrosion-erosion resistance. The refractory material comprises a CaO—ZrO.sub.2 composition containing a CaO component in an amount of 40% by mass to 60% by mass, wherein a mass ratio of the CaO component to a ZrO.sub.2 component is 0.67 to 1.5, and wherein the CaO—ZrO.sub.2 composition includes a eutectic microstructure of CaO crystals and CaZrO.sub.3 crystals, wherein a width of each of the CaO crystals observable in a cross-sectional microstructure is 50 μm or less.
COMPOSITIONS AND METHODS FOR THREE-DIMENSIONAL PRINTING
The present disclosure provides mixtures, systems, and methods for printing a three-dimensional (3D) object. In some aspects, the present disclosure provides a mixture for printing a 3D object, comprising a plurality of granulated particles. In some aspects, the present disclosure provides a mixture for printing a 3D object, comprising a plurality of precursor compounds configured to react to form a plurality of particles.
Negative electrode active material for lithium secondary battery, preparation method therefor, and lithium secondary battery comprising same
The present invention relates to a negative active material for a lithium secondary battery, a preparation method therefor, and a lithium secondary battery including the same. The negative electrode active material is a negative electrode material for a secondary battery, the negative electrode active material comprising a silicon-carbon composite comprising: a core comprising crystalline carbon and silicon particles; and an amorphous carbon-containing coating layer disposed on a surface of the core, wherein the negative electrode active material comprises: silicon oxide formed on a surface of the silicon particles; and an oxide of crystalline carbon, formed on a surface of the crystalline carbon, the average particle diameter (D50) of the silicon particles having a nanometer size, the proportion of O relative to Si in the silicon oxide is 30%-50%, and the proportion of O relative to C in the oxide of the crystalline carbon is 4%-10%.
COATING COMPOSITION FOR THE FOUNDRY INDUSTRY, CONTAINING PARTICULATE, AMORPHOUS SILICON DIOXIDE AND ACID
A coating composition is described, for use in the foundry, in particular comprising particulate, amorphous silicon dioxide (SiO.sub.2) and an aqueous phase having a pH of at most 5, and also coated, waterglass-bound foundry molding elements, especially coated, waterglass-bound foundry molds and foundry cores, which each comprise a coating composition of the invention. Further described is the use of a coating composition of the invention for producing a coating on a waterglass-bound foundry molding element and a method for producing a waterglass-bound foundry molding element (mold or core) coated with a water-containing refractory coating. Likewise specified is a kit whose contents include a coating composition of the invention.
POLYIMIDE FILM FOR GRAPHITE SHEET, AND GRAPHITE SHEET MANUFACTURED THEREFROM
Disclosed herein are a polyimide film for graphite sheets and a graphite sheet manufactured using the same. The polyimide film is fabricated by imidizing a precursor composition including: a polyamic acid prepared by reacting a dianhydride monomer with a diamine monomer; and an organic solvent, wherein the diamine monomer includes about 30 mol % to about 70 mol % of 4,4′-methylenedianiline and about 30 mol % to about 70 mol % of 4,4′-oxydianiline based on the total number of moles of the diamine monomer, 4,4′-methylenedianiline and 4,4′-oxydianiline being present in total in an amount of about 85 mol % or more based on the total number of moles of the diamine monomer.
Fe3C-DOPED GRADED POROUS CARBON POLYMER POTASSIUM ION ANODE MATERIAL, PREPARATION METHOD AND APPLICATION THEREOF
The disclosure relates to a Fe.sub.3C-doped graded porous carbon polymer potassium ion anode material as well as a preparation method and application thereof. In the method, previously prepared Fe.sub.2O.sub.3 is added into phenylamine, pyrrole, thiophene and cellulose acetate solutions, the above mixture is evaporated at the low temperature of 65-100° C., and then the evaporated product is calcinated to obtain a potassium battery anode material. This material consists of carbon nano sheets having different pore diameters, and has a graded porous structure of micropores, mesopores and macropores. Physical characterization results show that this material has the characteristics of large interlayer spacing, high specific surface area, rich defects and the like; electrochemical testing results show that this material has high reversible capacity and excellent cycle stability and rate performance.
Composition and process for pelletizing carbon-based materials for proppant and industrial applications
A method for producing an electrically-conductive pellet includes reducing a size of a first material. The method also includes wetting the first material to produce a first slurry. The method also includes introducing the first slurry into a fluidizer to produce a first pellet. The method also includes reducing a size of a second material. The second material is an electrically-conductive material. The method also includes wetting the second material to produce a second slurry. The method also includes applying the second slurry to the first pellet.
Electrode particles suitable for batteries
The disclosure relates to a carbon-based electrode material that has been graphitized to hold ions in the electrode of a battery and more particularly include carbide or carbide and nitride surfaces that protect the graphite core. The preferred batteries include metal ion such as lithium ion batteries where the carbon-based electrode is the anode although the carbon-based electrode may also serve in dual ion batteries where both electrodes may comprise the graphitized carbon-based electrodes. The electrodes are more amorphous than conventional graphite electrodes and include a carbide or nitride containing surface treatment.