单词：silica cycle
单词：silica cycle 相关文章
Water Cycle 水循环 All the oceans on earth are salty, while inland water is typically fresh. How does water become salty? We'll answer a listener's question -- today on Earth and Sky. DB: This is Earth and Sky. We recently visited the Austin Childr
(科普英语)Earth and Sky
Plant Self-defense Plants may appear to be helpless in the face of hungry,toothy animals but many plants have evolved interesting systems of self-defense. Coarse meadow grasses are a good example. If you run your finger along a blade of coarse grass,
英语听力文摘 English Digest
Fire Cycle 火灾规律 The El Nino phenomenon of 1997-98 unleashed torrential rain in some parts of the world, while creating abnormally dry conditions in others. And it sparked record numbers of wildfires. Learn more about climate and wildfire -- toda
(科普英语)Earth and Sky
AS IT IS 2015-07-14 Silica Sand Mining Worries Communities 美国硅砂矿引发社区担忧 The United States is increasing production of oil and natural gas through a process known as fracking. This process is sometimes called hydraulic fracking be
2015年VOA慢速英语(七)月
AILSA CHANG, HOST: Despite mounting evidence and a stream of dire warnings, federal regulators and mining companies failed to protect coal miners from toxic dust. MARY LOUISE KELLY, HOST: NPR and the PBS series Frontline spent more than a year lookin
2018年NPR美国国家公共电台12月
Classical music fans in Beijing are now embracing a massive work-the complete cycle of Beethoven's 9 symphonies with The Deutsche Kammerphilharmonie Bremen. Paavo Jarvi, an internationally famous Estonian conductor, is the artistic director of the or
2017CRI中国国际广播电台