pyrethrin ii造句

例句与造句

1. The structures of the natural insecticides pyrethrin I, R = CH 3 and pyrethrin II, R = CO 2 CH 3.
2. The active ingredients are extracted with organic solvents to give a concentrate containing the six types of pyrethrins : pyrethrin I, pyrethrin II, cinerin I, cinerin II, jasmolin I, and jasmolin II.
3. It is the most potent knockdown pyrethroid ( even stronger than pyrethrin II ) but it is relatively unstable, especially when exposed to light ( due to both the furan ring and the thiolactone group in the molecule ).
4. It's difficult to find pyrethrin ii in a sentence. 用pyrethrin ii造句挺难的