影响电化学腐蚀的外界因素有哪些?
参考答案:
1、溶解氧量。2、PH值。3、水的温度。4、水的流速。5、水中盐类的含量和成分。6、热负荷或热强度。7、应力。8、保护膜。
12月28日,以美军为主的北约驻阿富汗国际安全援助部队在喀布尔低调地举行了一个仪式,宣布正式()在阿富汗的战斗任务,美国在阿富汗经历了一场战争噩梦,迄今仍难以从这一泥淖中自拔。
A、启动
B、延长
C、重启
D、结束
In the following passage, there are 20 blanks representing the words that are missing from the context. You are to put back in each of the blanks the missing word. The time for this section is 20 minutes. Where do you really come from And how did you get (1) where you live today DNA studies suggest that all humans today (2) from a group of African ancestors who—about 60,000 years ago— (3) a remarkable journey. The Genographic Project is seeking to chart new (4) about the migratory history of the human species by (5) sophisticated laboratory and computer analysis of DNA contributed by hundreds of (6) of people from around the world. In this unprecedented and real-time (7) effort, the Genographic Project is closing the gaps of what science (8) today about mankind’s ancient migration stories. The Genographic Project is a five-year (9) partnership led by National Geographic Explorer-in-Residence Dr. Spencer Wells. Dr. (10) and a team of renowned international scientists and IBM researchers, are (11) cutting-edge genetic and computational technologies to analyze historical patterns in DNA (12) participants around the world to better understand our human genetic roots. (13) three components of the project are: to gather field research data (14) collaboration with indigenous and traditional peoples around the world; to invite (15) general public to join the project by purchasing a Genographic Project Public Participation Kit; (16) to use proceeds from Genographic Public Participation Kit sales to further (17) research and the Genographic Legacy Fund which in (18) supports indigenous conservation and revitalization projects. The Project is anonymous, non-medical, (19) , non-profit and non-commercial and all results will be placed in the (20) domain following scientific peer publication.