6results about How to "Avoid separation and purification" patented technology

The invention relates to the technical field of sodium / lithium ion battery negative electrode materials, and discloses a molybdenum-based negative electrode material and a preparation method and application thereof.The molybdenum-based negative electrode material comprises a nitrogen and sulfur co-doped carbon nano short rod, and the carbon nano short rod is filled with a core-shell type molybdenum-based nano roll; the core-shell type molybdenum-based nano roll comprises a molybdenum dioxide core and a molybdenum disulfide shell layer with a bent structure, and the number of the molybdenum disulfide layers is 12-35. The molybdenum-based negative electrode material provided by the invention is composed of a carbon nano short rod coating layer and a core-shell type MoO2-MoS2 nano roll filled in the carbon nano short rod coating layer; the MoO2-MoS2 nano-roll is obtained by homologous conversion of MoO3 nano short rods and has unique core-shell structure characteristics, and the MoO2-MoS2 nano-roll and the MoO3 nano short rods form a large number of heterogeneous interfaces to provide abundant reaction active sites for storing sodium ions or lithium ions and accelerating electrochemical reaction kinetics; according to the present invention, the MoS2 shell layer has the bending structure characteristic, and the number of the MoS2 layers is controlled to 12-35 through the confinement pyrolysis temperature and the sulfur-containing initiator consumption so as to obtain the excellent sodium / lithium storage performance, and the excellent rate performance and the excellent cycle stability are provided when the MoS2 / lithium battery is used;

This invention discloses a method for synthesizing potassium 4-methoxysalicylate based on supramolecular-assisted methylation, belonging to the field of organic synthesis technology. The process is based on supramolecular chemistry principles and includes the following steps: (1) Preparation of a macrocyclic host molecule-methylating agent complex loaded with a methylating agent: The macrocyclic host molecule and the methylating agent are reacted at pH 7-9 and 25-40℃ to form a complex solution; (2) One-pot preparation of the target product: 2,4-dihydroxybenzoic acid is salted with potassium hydroxide, potassium carbonate is added, and the above complex solution is added dropwise. A selective methylation reaction is carried out at 55-65℃. After the reaction is complete, post-treatment yields the product. This invention utilizes the molecular recognition function of the macrocyclic host to achieve highly selective methylation of the 4-hydroxyl group under mild conditions. This process has the advantages of simple operation, high safety, low waste, and recyclable host molecules. The yield of potassium 4-methoxysalicylate can reach over 85%, and the purity exceeds 99.0%.

The invention discloses a synthesis method of cis-4-methoxy cyclohexylamine hydrochloride, and belongs to the technical field of organic chemistry. The synthesis method comprises the following steps: 1, introducing air to react N-(benzyloxycarbonyl) hydroxylamine and 1, 3-cyclohexadiene under the catalysis of copper tetraphenylporphyrin to generate a compound I; 2, generating a compound II from the compound I and sodium methoxide under the action of boric acid ester; and 3, carrying out catalytic hydrogenation on the compound II, and reacting with hydrogen chloride to obtain the cis-4-methoxy cyclohexylamine hydrochloride. The method is simple to operate, and dangerous hydrogenation reaction conditions under high temperature and high pressure for reducing benzene rings are avoided; under the mediation of boric acid ester, the regioselectivity and stereoselectivity of the ring-opening reaction of sodium methoxide and a compound I are controlled to obtain a compound II with a cis-structure, and the compound II is subjected to catalytic hydrogenation and acidification salification to obtain a high-purity cis-stereoconfiguration product, so that a new path is provided for synthesis of cis-4-methoxy cyclohexylamine hydrochloride.

The present invention relates to a method for continuously producing 5-hydroxymethylfurfural and 2,5-furandicarboxylic acid. The method of the present invention starts from fructose-based carbohydrates, continuously produces important biomass-based platform compound 5-hydroxymethylfurfural and functional polymer material monomer 2,5-furandicarboxylic acid, and in the process of producing 2,5-furandicarboxylic acid, avoids the separation and purification process of 5-hydroxymethylfurfural, and has the advantages of simple process, low generation and emission of three wastes, environmental friendliness, etc.

The present invention belongs to the technical field of electron paramagnetic resonance and dynamic nuclear polarization, and specifically discloses a method for narrowing the ESR line width of light-induced free radicals applied to melt dynamic nuclear polarization. The method of the present invention adopts an α-dicarbonyl-containing and a methylene-containing β-dicarbonyl structure as a light-induced free radical precursor as shown in the following formula. The α-dicarbonyl structure can generate light-induced free radicals at liquid nitrogen temperature, and the methylene-containing β-dicarbonyl structure is prone to keto-enol interconversion in the solution. The aforementioned light-induced free radical precursor is dissolved to contain a certain amount of active D + In a solvent, during the keto-enol interconversion process, D gradually replaces the H on the methylene in the β-dicarbonyl to obtain a methylene-deuterated keto structure, which can be illuminated at liquid nitrogen temperature to obtain a deuterated free radical with a narrower ESR line width than the undeuterated structure.

The invention provides a method for simultaneously extracting rhaponticin, deoxyrhaponticin and anthraquinone compounds from rheum officinale, which can solve the problems of resource waste, high cost, complex process and low recovery rate caused by the fact that rhaponticin, deoxyrhaponticin and anthraquinone compounds cannot be simultaneously obtained by the existing method. The method comprises the following steps: cooking raw materials with boiling water to obtain a first filtrate and residues; adding industrial ammonia water and a first alcohol solution into the residues, stirring, extracting and filtering to obtain a second filtrate, concentrating, refrigerating and filtering to obtain a third filtrate and a first precipitate; modifying macroporous adsorption resin; dissolving the first precipitate with a small-polarity organic solvent, filtering to obtain a fourth filtrate and a second precipitate, concentrating, centrifuging, and combining a clear liquid with the first filtrate and the third filtrate to obtain a mixed liquid; adsorbing the mixed solution with modified macroporous adsorption resin, washing with water, eluting, concentrating and drying to obtain the anthraquinone compound; dissolving the second precipitate, filtering to obtain a fifth filtrate and a third precipitate, and concentrating and crystallizing to obtain a rhaponticin crude product; and refining.