1Pa的声压换算成声压级为多少?

题型:问答题

问题:

1Pa的声压换算成声压级为多少?

考点:音响调音员初级音响调音员初级
题型:问答题

对分离细胞的保存,下列说法错误的是()

A.用适量的含有1O%~20%灭活小牛血清的Hanks等培养液释稀重悬,培养液要求等渗,具有pH缓冲作用,并对细胞无毒性

B.细胞冷冻时降温的速度宜慢,解冻时升温的速度宜快

C.短期保存时,可放4℃保存较好

D.短期保存时,迅速改变细胞所处的温度,以免造成温度休克

E.长期保存时,应放入液氮罐中在深低温条件下保存,并加入二甲亚砜冷冻保护剂

题型:问答题
Every scientist has a childhood dream. A scientist in China once had a(n)       . He wished to grow a new type of rice which could produce a lot. This person is Yuan Longping        was born in 1930. He graduated from the Southwest Agricultural(农业) University in 1953. Yuan Longping came up with an idea for a hybrid rice in the 1960s. Since then, he has devoted himself to the research and development of new varieties(品种).
In 1973, together with other people, he        in the development of hybrid rice. This made China be a worldwide leader in rice production. For this, he was called Father of Hybrid Rice. In 1980, the technology for hybrid rice was        to the United States.        Professor Yuan’s hard work, China now produces enough rice to       her people every year.
In his spare time, he loves playing        violin and listening to music. Every night, he reads        half an hour before he goes to sleep. He likes swimming, too.
It is said that Professor Yuan is one of the        people in China. And he cares about       but his research.
Now Professor Yuan is working on developing super hybrid rice. He goes to the fields twice a day.
小题1:
A.dreamB.ideaC.thoughtD.will
小题2:
A.whereB.whomC.whichD.who
小题3:
A.successB.succeededC.successfullyD.successful
小题4:
A.givenB.grownC.showedD.introduced
小题5:
A.Because ofB.BecauseC.In orderD.For
小题6:
A.look afterB.feedC.sendD.fed
小题7:
A.anB./C.aD.the
小题8:
A.onB.inC.forD.to
小题9:
A.poorestB.richestC.cleverest D.most careful
小题10:
A.everythingB.anythingC.nothingD.something
题型:问答题

俄国批判现实主义文学的奠基人、“自然派”文学的开创者是( )

A.普希金

B.托尔斯泰

C.果戈理

D.契诃夫

题型:问答题

早餐前环境准备包括,餐台、餐椅摆放整齐无坏损、()环境清洁。

A、台花摆放标准

B、摆台摆放标准

C、水杯摆放标准

D、台布铺放标准

题型:问答题

非淋菌性 * * 炎的主要感染源是

A.链锁状杆菌
B.葡萄球菌
C.痘病毒
D. * * 瘤病毒
E.沙眼衣原体及支原体

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