细胞膜内褶

Fish live in water, but do they drink it? The answer is yes, but how fish drink water depends on where they live. Water gets into a fish's body through osmosis, the process in which water diffuses from a higher to a lower concentration. For example,

发表于:2018-12-03 / 阅读(56) / 评论(0) 分类 初学者听力文摘精选

Rachel Lee: The housing market keeps losing steam. Sales of previously owned homes fell 5. 7% last month according to the National Association of Realtors. If you're looking for a house , the group's

发表于:2018-12-05 / 阅读(39) / 评论(0) 分类 商业报道2006年

For something that could revolutionize the world, its come along very slowly. The fuel cell was invented in 1839, but there was little development until the 1950s when NASA started to use them in space where they are still used today. Now, after yea

发表于:2018-12-30 / 阅读(59) / 评论(0) 分类 国家地理2008年

VOICE ONE: This is SCIENCE IN THE NEWS in VOA Special English. I'm Barbara Klein. VOICE TWO: And I'm Steve Ember. This week, we will tell about an American study of the brain disorder schizophrenia. We tell about cars that use hydrogen as fuel. And,

发表于:2019-01-11 / 阅读(47) / 评论(0) 分类 VOA慢速英语2008(十)月

For something that could revolutionize the world, its come along very slowly. The fuel cell was invented in 1839, but there was little development until the 1950s when NASA started to use them in space where they are still used today. Now, after year

发表于:2019-01-22 / 阅读(39) / 评论(0) 分类 自然百科2008年

There are several kinds of odor preventing and odor destroying treatments for textiles. For the most part, they work by killing or inhibiting the bacteria and fungi that cause odors. For example, these socks contain Quaternary Ammonium Compounds, or

发表于:2019-02-23 / 阅读(36) / 评论(0) 分类 英语时差8,16