1·Scientists first posed this question in the mid-1990s, after researchers came upon a chemical agent that in rodents seemed to reproduce many of caloric restriction's benefits.
科学家首次提出这个问题是在20世纪90年代中期。当时，研究人员偶然发现一种化学药剂，这种药剂在啮齿动物身上似乎可以发挥和热量限制相同的正面效果。
2·Research and Development of Chemical Agent;
产品研究与开发；
3·A chemical agent that kills eggs, especially the eggs of insects.
一种杀灭螨虫的化学药剂。
4·This is a chemical agent that destroys plants or inhibits their growth.
这是一种能除草或抑制其生长的化学药剂。
5·The chemical agent must be delivered in order to threaten someone, and the threat can be countered.
化学毒剂必须通过投放来实现威胁，而且这种威胁可以防范。
6·A certain injecting temperature is necessary at the beginning of injecting the chemical agent m.
在启动过程中掺入化学剂的温度对油井生产有一定的影响。
7·Lethal chemical Agent Countermeasures reviews some of the measures taken to defend against chemical attack.
致死性化学毒剂对策，综述了防御化学袭击的措施。
8·Use of a chemical agent to achieve diversion during matrix stimulation or similar injected treatments.
在基岩增产处理作业或类似的注入处理作业中使用一种化学剂来实现导流。
9·Each micro machine would be equipped with a sensor, either a video camera or a chemical agent detector.
每个微型机器人将配备一个传感器，可能是视频摄像机或化学剂探测器。
10·The modified bentonite is made by fixing modified chemical agent and bentonite at a proper ratio after maturity.
改性膨润土由改性剂与膨润土按一定的比例混合熟化后制成。