请输入您要查询的英文单词:

 

单词 pyrethrine
释义 pyrethrine Chem.|paɪˈrɛθraɪn|
Also 9 -in.
[ad. F. pyrétrine (Parisel, 1833): see pyrethrum and -ine5.]
The substance to which the sialagogic action of pyrethrum root is due; it appears, when pure, to be a white crystalline alkaloid. Hence pyˈrethric a., in pyrethric acid, a substance obtained by the action of potassium hydroxide on pyrethrine.
1838Thomson Organic Bodies 815 To the acrid substance M. Parisel has given the name of pyrethrin. But it appears.. that it is not a simple vegetable principle as he supposed, but a compound of two oils and a resin.1881Watts Dict. Chem. VIII. 1699 s.v. Pyrethrum, R. Buchheim, by evaporating to dryness the alcoholic extract of Radix pyrethri, and exhausting the residue with ether, obtained a crystalline substance, pyrethrin, which melted at the heat of the body, and was resolved by alcoholic potash into pyrethric acid and piperidine.1895Dunstan & Garnett in Jrnl. Chem. Soc. LXVII. 101 We propose provisionally to name it pellitorine. It is very probable that it is the same substance as that isolated..by Buchheim, in 1876, and named by him pyrethrine.
随便看

 

英语词典包含277258条英英释义在线翻译词条,基本涵盖了全部常用单词的英英翻译及用法,是英语学习的有利工具。

 

Copyright © 2004-2022 Newdu.com All Rights Reserved
更新时间:2024/12/22 16:25:36