6results about How to "Stable particle size distribution" patented technology

The invention relates to the technical field of lithium iron phosphate production, and discloses a carbon-coated titanium-doped lithium iron phosphate positive electrode material and a preparation method thereof.The preparation method comprises the following steps that 1, a ferrous solution and a phosphorus source solution are mixed in proportion, dopamine hydrochloride is added, a pH regulator is dropwise added in the stirring state, the pH of the solution is adjusted to 4.0-5.5, a reaction is conducted, a titanium source solution is added, and a reaction solution is obtained; after uniformly stirring, continuously dropwise adding a pH regulator to regulate the pH value of the solution to 5.5-6.5; the iron phosphate octahydrate coated with the titanium-embedded polydopamine is obtained; 2) calcining the titanium-embedded polydopamine-coated ferrous phosphate octahydrate in an inert gas atmosphere to obtain carbon-coated titanium-doped anhydrous ferrous phosphate; 3) mixing the carbon-coated titanium-doped anhydrous ferrous phosphate with lithium phosphate and a carbon source, ball-milling, mixing, spray-drying and calcining to obtain a carbon-coated titanium-doped lithium iron phosphate positive electrode material; the synthesis process is simple, and energy consumption is reduced.

This invention belongs to the field of lithium-ion battery electrolyte material preparation technology, and provides a solid lithium hexafluorophosphate with low fine crystal content and its preparation method. The preparation method involves adding lithium fluoride to anhydrous hydrogen fluoride to form anhydrous hydrogen fluoride slurry. A portion of the anhydrous hydrogen fluoride slurry and phosphorus pentafluoride gas are fed into a primary continuous reaction crystallizer. The resulting slurry is subjected to low-temperature fractionation to form a first stream and a second stream. The second stream enters a secondary continuous growth crystallizer and continues to react with phosphorus pentafluoride gas, followed by solid-liquid separation to obtain a solid wet product and mother liquor. The first stream, another portion of the anhydrous hydrogen fluoride slurry, and a portion of the mother liquor enter a pre-conditioning section, and the resulting pre-conditioned stream is returned to the feed end of the primary continuous reaction crystallizer. The solid wet product is then subjected to low-temperature washing and programmed vacuum drying to obtain the final product. This method, through the combination of fractional reflux, mother liquor participation in pre-conditioning, and continuous growth processes, reduces fine crystal entrainment and improves particle size distribution stability.

The invention provides a system and method for reducing filtered moisture of fine-ground hematite and limonite, and the system sequentially comprises a ball mill used for carrying out wet type fine grinding on raw hematite and limonite; the classification cyclone and the ball mill form a closed-loop ore grinding loop and are used for controlling the overflow granularity; the thickener is used for receiving overflow of the grading cyclone and is used for increasing the ore pulp concentration; the disc vacuum filter is connected with the thickener underflow and is used for carrying out vacuum filtration on the concentrated ore pulp; the water ring type vacuum pump is used for providing a filtering vacuum degree for the disc vacuum filter; wherein a cationic polyacrylamide flocculating agent is added into the thickener. According to the system, on the premise that a filter aid is not used and a filter press is not replaced, through four-parameter coupling of'granularity-concentration-flocculation-vacuum ', the filtering driving force is upgraded from'single vacuum degree' to a new mechanism of'controllable capillary channel structure and accurate vacuum degree matching ', and the water content of a filter cake is smaller than or equal to the pelletizing requirement.

The invention discloses wear-resistant eutectic high-entropy alloy powder for additive manufacturing. The wear-resistant eutectic high-entropy alloy powder comprises the following chemical components in percentage by atom: 16.5%-20.5% of Al, 28.0%-31.5% of Co, 9.0%-11.0% of Cr, 8.5%-10.5% of Fe, 29.0%-31.5% of Ni, 1.8%-2.4% of W, 26.0%-30.5% of the sum of Cr and Al, 18.5%-22.8% of the sum of Al and W and the balance of inevitable impurities. The contents of C, S and P elements in the impurity elements are not more than 150ppm, and the contents of O and N elements are not more than 100ppm. The hardness of the high-entropy alloy is remarkably improved, and the high-entropy alloy has good wear resistance. Meanwhile, the invention further discloses a preparation method. Polishing and cleaning raw materials; burdening and charging; vacuumizing and replacing gas; smelting under the protection of argon; carrying out argon atomization; screening by an airflow classifier; screening with a vibrating screen.

The invention discloses a preparation method of conductive paste for a solar cell, and relates to the technical field of solar cell preparation. The preparation method comprises the following steps: adding a copper source, a surfactant, a dispersant and a brightness modifier into a solvent to obtain a first mixed solution; adding a reducing agent and a chelating agent into a solvent to obtain a second mixed solution; the first mixed solution and the second mixed solution are mixed according to the preset volume ratio, a third mixed solution is obtained, and seed copper powder with the preset mass fraction is added into the third mixed solution; the third mixed solution after the reaction is sequentially subjected to sedimentation cooling treatment, centrifugal treatment, drying treatment and grinding treatment, micron-sized copper powder is prepared, a conductive silver layer is deposited on the surface of the micron-sized copper powder through chemical reduction reaction, silver-coated copper powder is prepared, and the conductive paste is prepared through the silver-coated copper powder. The micron-sized copper powder prepared through the method can meet the high target size interval yield, the preparation cost is low, and the process compatibility is high.

The application belongs to the technical field of molecular imaging and biomedical materials, and particularly relates to a construction method of a radioactively labeled magnetic T1-T2 synergistic MRI-PET bimodal imaging probe and application thereof. The polyphenol substance is dissolved in methanol, the pH is adjusted, SPIO is dispersed in tetrahydrofuran, after mixing, the water-phase SPIO modified by the polyphenol is obtained. Then, the streptavidin is dissolved in water, the polydopa coating layer is formed by in-situ polymerization of the polydopa and is coupled with the streptavidin, the biotin-modified targeting ligand is combined, the targeted MRI probe is obtained, and finally the radioactive metal element such as Cu, 64 Cu, 68 Ga is efficiently chelated to obtain the T1-T2 synergistic MRI-PET bimodal probe, the probe has the advantages of strong stability, high hydrophilicity, good biocompatibility, high relaxivity, good tumor targeting, high sensitivity of PET for whole body quantification, high soft tissue contrast of MRI T1-T2 and high spatial resolution.