Sometimes it is hard to see the light, especially it lies in the invisible spectrum, like ultrared, ultraviolet radiation. But if you long to see the unseeable, you might interested to hear that under certain conditions people can catch a glimpse of

发表于:2018-12-24 / 阅读(35) / 评论(0) 分类 2015年Scientific American(一)月

A nightlight may keep those monsters under the bed. But it may also open the door to the blues. Because a new study reveals that animals exposed to light all night long show signs of clinical depression. If you have access to electricity, you no doub

发表于:2018-12-24 / 阅读(49) / 评论(0) 分类 Scientific American(十)月

OPEC will cut its oil output by 1.5 million barrels a day starting in November, with chances of more cuts to come. But from Paris, Lisa Bryant reports the announcement was met by a further drop by financial markets. OPEC hopes that by cutting output

发表于:2019-01-13 / 阅读(77) / 评论(0) 分类 VOA标准英语2008年(十月)

DAVID GREENE, HOST: I mean, let's listen to this. (SOUNDBITE OF TV SHOW, STAR TREK: THE ORIGINAL SERIES) JAMES DOOHAN: (As Captain Montgomery Scott) Ready to transport. WILLIAM SHATNER: (As Captain James T. Kirk) Energize. D. GREENE: Yes, the familia

发表于:2019-01-16 / 阅读(89) / 评论(0) 分类 2017年NPR美国国家公共电台7月

But this still doesn't explain why light is able to pass through glass rather than being absorbed as with most solids. 但是这还是不能解释为什么光可以穿透玻璃而不是像其他大多固体那样被吸收。 For that, we need to go a

发表于:2019-01-17 / 阅读(49) / 评论(0) 分类 TED演讲教育篇

OPEC Agrees to Reduce Oil Output Kerry Sheridan Oil prices edged higher Tuesday after ministers from the Organization of Petroleum Exporting Countries (OPEC) agreed to reduce output. OPEC ministers ha

发表于:2019-01-31 / 阅读(60) / 评论(0) 分类 VOA2004(上)--各类新闻