单词:rarefactions
[医] 稀疏[状态], 疏松[状态]
n. a decrease in the density of something
单词:rarefactions 相关文章
The preservation of embryos and juveniles is a rate occurrence in the fossil record. The tiny, delicate skeletons are usually scattered by scavengers or destroyed by weathering before they can be foss
By Nick Wadhams Nairobi 26 July 2007 Four rare mountain gorillas have been killed after gunmen crept up on them and opened fire in the Democratic Republic of Congo's Virunga National Park. Nick Wadhams has more on the story from Nairobi. The gorillas
Rare Minerals May Be in North Korea 稀有矿物质可能在朝鲜发现 Hello and welcome back. Im Jim Tedder in Washington. Today we are going to talk about something that is worth a lot of money, and it is buried in the ground. Were not exactly go
STEVE INSKEEP, HOST: We have an investigation this morning of drug companies gaming a system designed to help desperate patients. It's a story of orphan drugs. DAVID GREENE, HOST: These are life-saving drugs that pharmaceutical firms don't develop be
Rare but Deadly By Susan Brink /2005, U.S. News World Report . All rights reserved with permission. Distributed by Tribune Media Services International. Simple, cheap blood tests could save thousands
Pre-Listening Vocabulary rare: not common irrational: not reasonable classified: grouped by like qualities provoke: to excite or bother a living thing and cause a reaction initiate: to be the one to start something delicacy: a type of food that is ra
By Malcolm Brown Washington 09 October 2007 A collection of newly available photographs is shedding fresh light on those who carried out the Nazi holocaust. The public now has the chance to see the contents of an album, thought to have belonged to a
By Noel King Kigali 26 September 2007 A female mountain gorilla has been found dead in eastern Democratic Republic of Congo's Virunga National Park, bringing the death toll of the rare animals to10 so far this year, wildlife groups said Wednesday. Fi
By Kari Barber Dakar 20 August 2007 A fifth rare mountain gorilla has been found shot dead inside the Virunga National Park in eastern Democratic Republic of Congo. In an unusual attack last month the five endangered animals were killed and their car
Nicholas Willis has won a bronze medal in the men's 1500-meter race at the Beijing Olympics. He is one of many athletes who lives in the United States but was born in another country. VOA's Jim Stevenson has more on the middle distance runner from N
By VOA News Bulawayo, Zimbabwe 18 October 2007 We bring you a rare look inside the troubled southern African nation of Zimbabwe. Today, this nation of between 10 million and 12 million is teetering on the edge of what a member of its own parliament i
By Al Pessin Pentagon 06 December 2007 The top coalition commander in Iraq had some positive things to say Thursday about Syria and other countries and factions that have contributed to instability in Iraq in the past. But U.S. General David Petraeus
Economics Report - Limits on Rare Earth Exports Get China in Trade Dispute 经济报道 - 稀土限制使得中国陷入贸易纠纷 This is the VOA Special English Economics Report. 这里是美国之音慢速英语经济报道。 The United States,
By David Byrd Washington 29 May 2008 For most Americans, badminton is a backyard game played at parties and barbecues. But for Eva Lee, it is very serious - she is one of five members of the U.S. Badminton team that will be competing for gold at the
Rare Violins Play Starring Role in Concert Stradivarius instruments, especially Stradivarius violins, are known the world over for their exquisite beauty, unparalleled craftsmanship and extraordinary sound. Six of the rare instruments are owned by th
RACHEL MARTIN, HOST: Scientists have developed a better test for a very rare brain disease. And as NPR's Rae Ellen Bichell reports, this test could lead to new ways to diagnose more common diseases like Parkinson's and Alzheimer's. RAE ELLEN BICHELL,
By Kurt Achin Seoul 03 December 2007 A senior U.S. envoy is in the North Korean capital to discuss Pyongyang's cooperation in efforts to peacefully end its nuclear weapons capabilities. The focus of the visit is to preview a promised declaration of a
BEIJING, March 15 (Xinhua) -- China's restrictions on rare earth exports are justified and are in line with World Trade Organization rules, Shen Danyang, spokesman for the Ministry of Commerce, said Thursday. The policy aims to protect resources and
China is the world's largest producer and exporter of rare-earths. These are elements which are critical to the manufacturing of high-tech products, including smartphones, wind turbines and car batteries, among other things. However, the rare-earth i
Two extremely rare Bengal white tiger cubs have been born at the wildlife center of the Czech Republic's Liberec Zoo, and are proving popular with visitors. These tiger cubs weigh 6 kilos 13 pounds, and were born two months ago. White tigers are the