单词：national institute of standards and technology (nist)
单词：national institute of standards and technology (nist) 相关文章
This is Scientific Americans 60-Second Science. Im Karen Hopkin. This will just take a minute. Many of the key molecules for life have a specific direction, or handedness: DNA twists to the right, amino acids to the left. Now scientists at the Nation
Scientific American(四)月
Also: The Library of Congress adds to its National Recording Registry. And a listener in Iran wants to know more about the Massachusetts Institute of Technology. Transcript of radio broadcast: 05 June 2008 HOST: Welcome to AMERICAN MOSAIC in VOA Spe
VOA慢速英语2008年（六）月
Education Report - No National Standards: A Strength or Weakness of US Schools This is the VOA Special English Education Report. What American students are expected to learn has long been different from state to state. We talked last week about the t
2011年VOA慢速英语(六)月
Next year will mark the 110th anniversary of a U.S. government agency that is unknown to most Americans. Yet its work affects their everyday lives in countless ways. Generations knew the agency as the National Bureau of Standards. When it was founded
VOA标准英语2010年(十一)月
Last week there was a lot of talk by teachers, parents and MPs about bringing in national standards in primary schools. A national standard is a list of things that children must be able to do each year. Maybe the standard for year 1 is to be able to
新西兰英语
China is now on the front lines of efforts to develop energy sources that can balance the goals of sustaining economic growth and protecting the environment. Decisive action is needed to strengthen policy frameworks across the country to reach that g
cctv9英语新闻2015年