Cells cannot remain alive outside certain limits of temperature and much narrower limits mark the boundaries of effective functioning. Enzyme systems of mammals and birds are most efficient only withi

发表于:2018-12-01 / 阅读(200) / 评论(0) 分类 新东方背诵文选

[00:04.78]Lesson 45 Dialogue [00:10.34]Eric,an Englishman,is visiting Charlie in the USA. [00:16.61]CHARLIE:How long are you planning to stay over here? [00:20.66]ERIC:I've got three weeks altogether.What do you suggest I see? [00:26.72]CHARLIE:What

发表于:2018-12-13 / 阅读(106) / 评论(0) 分类 高中英语人教版高三

This is Scientific American's 60-Second Science, I'm Karen Hopkin, this will just take a minute. Shakespeare once said: A rose by any other name would smell as sweet. And that is true today as it was 400 years ago. What's different now, though, is th

发表于:2018-12-24 / 阅读(78) / 评论(0) 分类 Scientific American(四)月

Graph Search的理念在于,以谷歌搜索引擎发掘互联网信息的方式,发掘Facebook网站社交图谱的含义。Graph Search扩展了Facebook的核心使命:不仅帮助用户与已知的他人建立联系,还能成为一款发现工

发表于:2019-01-05 / 阅读(61) / 评论(0) 分类 英语新闻视频

Some bacteria have adapted to super cold environments for millions of years. And scientists have isolated some of the essential genes that allow bacteria to tolerate their harsh living conditionsbecause these same genes might help in the creation of

发表于:2019-01-11 / 阅读(74) / 评论(0) 分类 英语杂谈

The Macondo well operated by BP in the Gulf of Mexico has now been capped with a star adornment that commemorates the 11 people killed when the rig operating on the water surface above the site exploded on April 20. Clean-up efforts continue, though,

发表于:2019-01-14 / 阅读(66) / 评论(0) 分类 VOA标准英语2010年(十一)月