3results about How to "Thermal stability" patented technology

The present invention relates to a positive electrode active material for a secondary battery which is a lithium composite transition metal oxide including nickel (Ni), cobalt (Co), and manganese (Mn), wherein the lithium composite transition metal oxide includes the nickel (Ni) in an amount of 65 mol% or more and the manganese (Mn) in an amount of 5 mol% or more based on a total amount of transition metals, and at least one particle growth-promoting element selected from the group consisting of strontium (Sr), zirconium (Zr), magnesium (Mg), yttrium (Y), and aluminum (Al), wherein the electrode positive active material is composed of a single particle.

This invention discloses a hot melt adhesive for high-temperature protective clothing and its preparation method, comprising the following raw materials: Fischer-Tropsch wax, styrene-isoprene-styrene block copolymer with 0% diblock content, styrene-isoprene-styrene block copolymer with 20-30% diblock content, styrene-isoprene-styrene block copolymer with 40-50% diblock content, rosin resin, petroleum resin, ethylene-vinyl acetate copolymer, and antioxidant. This hot melt adhesive requires no toxic solvents, possesses both heat resistance and water resistance, and is suitable for high-temperature protective clothing. The preparation method of this hot melt adhesive involves heating and mixing polymer materials without adding any solvents or toxic substances during the preparation process, reducing the risk of toluene poisoning, completely solving the problems of solvent evaporation and recovery, and, more importantly, eliminating safety hazards in the storage and use of organic chemicals, achieving environmentally friendly, safe, and efficient production.

The application provides a device and method for dynamically adjusting an axial temperature gradient in a crystal growth process, and belongs to the technical field of silicon carbide crystal production. The device comprises a crucible main body, a crucible cover provided with an opening, a seed crystal rod, and a temperature adjusting device; one end of the seed crystal rod is connected to a seed crystal holder for carrying a seed crystal, the seed crystal holder is placed in the crucible main body during the growth process, and the other end is sleeved with the temperature adjusting device; the temperature adjusting device comprises an adjusting assembly, a connecting assembly, and a transmission assembly; the adjusting assembly is made of graphite soft felt and is provided with a through hole in the center, and the seed crystal rod passes through the through hole; the transmission assembly is connected to the adjusting assembly through the connecting assembly and controls the adjusting assembly to move up and down along the seed crystal rod to realize axial temperature regulation; the adjusting assembly is in a contracted state during the up and down movement, and is expanded through the transmission assembly when being in contact with the crucible cover or the seed crystal holder. The scheme realizes axial temperature regulation in the crystal growth process.