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Should the president have spoken sooner? Well, I think those decisions -- I'm going to leave that to the White House. I think he had Secretary Napolitano out there speaking, and I think she clarified that one of... the statement she made yesterday. I

发表于:2018-12-20 / 阅读(68) / 评论(0) 分类 CNN2010年(一)月

This is Scientific American's 60-Second Science. I'm Steve Mirsky. Got a minute? On June 4th we told you about iron snowflakes on Mercury. Today we have some radical news about the atmosphere of Venus. Literally, a radical is a molecule that reacts e

发表于:2018-12-24 / 阅读(48) / 评论(0) 分类 Scientific American(六)月

Erythromycin,红霉素 Azithromycin,阿奇霉素 Clarithromycin,克拉霉素 Fluoroquinolones and their derivatives (e.g. levofloxacin),多西环素(如:脱氧土霉素) Tetracyclines (e.g

发表于:2019-01-03 / 阅读(41) / 评论(0) 分类 医务英语

分集介绍:导数,商数,正弦和余弦 Derivatives.of.products.quotients.sine.cosine

发表于:2019-01-05 / 阅读(285) / 评论(0) 分类 麻省理工学院公开课:单变量微积分

Ben Cooper is more than just a musician: hes a storyteller, and a good one at that. Cooper, who previously was one-half of Electric President, brings his voice to the table as Radical Face and has now completed the second installation of his musical

发表于:2019-02-08 / 阅读(35) / 评论(0) 分类 英文摇滚歌曲

In remarks in Washington on Tuesday, President Barack Obama denounced a $3.5-trillion Republican budget plan, saying it would harm middle class Americans and set back the nation's economic recovery. Mr. Obama's speech sharpened his message to voters

发表于:2019-02-18 / 阅读(50) / 评论(0) 分类 英语新闻