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- But aerogel is able to slow the particles down to a halt within the space of a few dozen microns, and preserve them better than any known substance. 但是气凝胶能够让这些颗粒减速并最终在几十微米的距离上停下来，比其他任何已知物质更好的保护它们。
- Sodium carbomer used as a key ingredient in the composition of the present invention to provide the necessary consistency for long lasting(minimum 24 hours) action, is a known substance. 本发明之组合物中的一种关键成份是卡波姆钠，它能为本组合物提供必要的稠度以保持长时间(至少24小时)药效。
- Endorphins, a known substances produced in brains is an opioid receptor agonist which the brain produce in the presence of pain stimulus. 如果你一连几天、一天几次进行实验：诱发某人身感疼痛，再用吗啡为他止疼，到最后一天，悄悄用盐水取代吗啡，你会发现，此时盐水也能止痛。
- Biocatalysis is currently employed to produce known substances more economically and for the synthesis of new compounds. 目前生物催化主要用于更加经济简便的合成已知和未知的化合物。
- He professed to know nothing about the matter. 他声称对此事一无所知。
- When it comes to German, I know nothing. 谈到德语，我一窍不通。
- Nothing is known of the authorship of the book. 无人知道该书是何人所写。
- This substance is known as plaque. 这种物质叫做牙斑。
- He was known to be a young man with lofty ideals. 人们都知道他是一个有抱负的青年。
- This is the most dangerous substance known to man. 这是人类已知的最危险的物质。
- I take it you know what a stethoscope is. 我想你知道听诊器是个什么东西。
- The place is known for its handicraft products. 这地方因出手工艺品而出名。
- Diamond is the hardest substance known. 钻石是已知物质中最硬者。
- I know where the picturesque old-world village is. 我知道那个风景如画的古老村寨在哪儿。
- It's known as the most dangerous part of the city. 那地方都知道是市内最危险的地段。
- He's sometimes been known to sit there all day. 有时能见到他整天坐在那里。
- That iron is a good conductor is known to us all. 铁是良导体这是我们大家都知道的。
- People in this town know him as a lunatic. 这个镇上的人们称他为疯子。
- Now I know where to go when I feel homesick. 现在我知道想家的时候该去哪儿了。
- I know all the ins and outs of our school building. 我知道我们教学大楼的一切情况。
