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  Vitamins, also known as vitamins, are a class of low-molecular-weight organic chemicals. Vitamins are catalysts for biochemical reactions and metabolism of animals, and are an indispensable micronutrient for maintaining normal physiological functions and normal growth and development of animals. Vitamins are the earliest […]

(1) 20% solution is reacted with a concentrated aqueous solution of ethylene oxide, and then neutralized with hydrochloric acid; (2) in the methanol solution of choline, added hydrochloric acid, neutralized and then refined; (3) Anhydrous chloroethanol reacts with trimethylamine. The reaction was carried out […]

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