单词:cesium iron alum
单词:cesium iron alum 相关文章
1: I am Andy. 2: Hello! 3: Good morning. 4: This is Kay. 5: This is Miss Dizzy. Your English teacher. 6: How do you do. 7: Hi! 8: Good bye! 9: So long. 10:Bye-bye! A: Hello! I am Andy. Hello! I am Mr. Write. I am Bobby. I am Kay. B: Good morning Mr.
[00:06.37]The United States has a new official clock. [00:10.95]The clock began operating late last year in the American city of Boulder,Colorado. [00:18.39]Experts say the new clock is so exact that it will neither gain nor lose so much as one secon
Youve given some thought to oxygen, carbon, uranium. But youve probably never mused about the element ytterbium, symbol Yb. A new study by scientists at the National Institute of Standards and Technology, or NIST, says that ytterbium could find a rol
Donny Hathaway, who gained fame in the 1970s as a Grammy Award-winning singer, songwriter and producer, left behind some of soul music's most-compelling tunes, including his 1973 hit, Love, Love, Love. The smooth jazz rendition from Kirk Whalum's alb
This is the VOA Special English Development Report. Dye can bring a little color to life. Most clothing is colored with dyes. Modern, manufactured dyes can be costly. Natural dyes from plant and animal products have been used since ancient times. So
This is the VOA Special English Development Report. Dye can bring a little color to life. Most clothing is colored with dyes. Modern, manufactured dyes can be costly. Natural dyes from plant and animal products have been used since ancient times. So