单词：portable gas chromatograph
单词：portable gas chromatograph 相关文章
A little old lady goes to the doctor ... and says,
英文笑话
Broadcast: Feb 13, 2003 Demand for electricity is growing in Mexico, but the state-owned oil company, known as Pemex, is reducing the amount of natural gas it can provide for electrical generation. Th
VOA2003（上）-国际时讯
This is Scientific Americans 60-Second Science. Im Sophie Bushwick. Got a Minute? What's the best way to find out if an unknown mixture contains a specific substance, like an environmental contaminant? You could use an expensive, bulky gas chromatogr
Scientific American(八)月
By Deborah Block Washington 13 May 2008 As the price of gasoline continues to rise in the U.S., more Americans are buying smaller, more fuel-efficient vehicles. Others are holding on to their big cars, in hopes that gas prices will eventually go down
VOA标准英语2008年（五月）
Do you have gas? Beginners. What kind of a question is that? Are you talking about my body or my car? Well, actually, I am talking about your car. Gas, or petrol, as it is called in England, is a big subject at the moment. Driving a car has become re
英语博客 A cup of English
By Robert Berger Jerusalem 02 April 2008 Israel is strengthening security on its home front in a sign of war jitters. As Robert Berger reports from VOA's Jerusalem bureau, Israel is casting a wary eye toward Iran. Israel's security Cabinet has decide
VOA常速英语2008年（四月）