本文研究建立了溴苯腈在土壤及水中的残留测定方法.A method was developed for the residue analysis of bromoxynil in soil and water.研究了一种合成2, 6- 二氯苯腈的新方法, 优化出合成反应的最佳条件.This paper studies a new synthetic method of 2, 6 - dichlorobenzonitrile, and ab...
The orbits of such faint asteroids are not yet known.但是对于这样暗的小行星的轨道,迄今尚未弄清.Asteroids,also known as “minor planets”,are numerous in the outer space.小行星,亦称为“小型行星”,在外太空中不计其数。Most stars probably have their quota of planets, ...