Abstract: Provided in the present disclosure are a cobalt-free high-nickel positive electrode material, a preparation method therefor and use thereof. The cobalt-free high-nickel positive electrode material comprises a cobalt-free high-nickel matrix material and a coating layer coated on the cobalt-free high-nickel matrix material, wherein a chemical formula of the cobalt-free high-nickel matrix material is LimNixMnyO2, where 0.2?m?0.8, 0.4?x?0.95, and 0.05?y?0.6; and the coating layer is TiBzO1-z, where 0.2?z?0.8. The cobalt-free high-nickel positive electrode material obtained by means of modification using the coating layer TiBzO1-z has good acid resistance and wear resistance, high mechanical strength and excellent conductivity; and when the cobalt-free high-nickel positive electrode material is used for a lithium ion battery, the high-temperature cycling performance, capacity and initial efficiency of the lithium ion battery are greatly improved.

Abstract: The present invention belongs to the field of medicinal chemistry and relates to a class of substituted tricyclic compounds as PRMT5 inhibitors and the use thereof. Specifically, the present invention provides a compound represented by formula (A) or an isomer, pharmaceutically acceptable salt, solvate, crystal or prodrug thereof, a preparation method therefor, a pharmaceutical composition containing the compounds, and the use of the compounds or the composition for treating a disease mediated by PRMT5. The compounds of the present invention show significant inhibitory activity on PRMT5.

Abstract: The present disclosure provides a cobalt-free and nickel-free positive electrode material and a preparation method therefor, and a battery. The preparation method includes: preparing a cobalt-free and nickel-free matrix material, and mixing the cobalt-free and nickel-free matrix material, a lithium source, and a divalent manganese compound for reaction to obtain the cobalt-free and nickel-free positive electrode material. By adding the divalent manganese compound, the generation of lamellar LiMnO2 and spinel LiMn2O4 is inhibited, the generation of lamellar Li2MnO3 is promoted, and the cycle performance of the material is improved.