对二氧化碳的纯度和压力有何要求?

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问题:

对二氧化碳的纯度和压力有何要求?

考点:型砂工型砂工题库
题型:问答题 简答题

阅读下面短文,完成相关任务。

For more than one month, people in China have been worried about the fate(命运)of the 239 people, including 154 Chinese passengers, on board Air Malaysia Flight MH370. However, today no matter how sad we are and how many details(详细资料)that are not clear, it is certain that flight MH370 broke down in the Indian Ocean and no one on (44)it is alive. All the people in the world can do is to continue to look for the wreckage(残骸), talk with the Malaysian government for more information and accept the terrible fact.

People in China have been very disappointed with Malaysia Airlines these days. They do their best to show the Malaysian government that we will never give up knowing the truth. On the other hand, the number of Chinese people who choose to take a trip in Malaysia has been smaller and smaller. Many Chinese people including some famous movie stars say that they will never go to Malaysia any more.

At present, there’s a totally new expression coming out after this event. That is, “Don’t be so Malaysia.”45 People use it to describe someone who is unbelievable and likes telling lies to hide the truth.

根据短文内容及有关时事回答1—3题。

小题1:Did the plane crash in the Indian Ocean?

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小题2:How many Chinese are there on Air Malaysia Flight MH370?

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小题3:What do many movie stars say after the event?

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小题4:划线的“it”指代什么?请用原文中的词汇或句子表达。

                                                                    

小题5:把划线部分翻译成汉语。

                                                                       

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在平面直角坐标系xOy中,第Ⅰ象限存在沿y轴负方向的匀强电场,第Ⅳ象限存在垂直于坐标平面向外的匀强磁场,磁感应强度为B。一质量为m.电荷量为q的带正电的粒子从y轴正半轴上的M点以速度v0垂直于y轴射入电场,经x轴上的N点与x轴正方向成θ=60°角射入磁场,最后从y轴负半轴上的P点垂直于y轴射出磁场,如图所示。不计粒子重力,求:

(1)粒子过N点时速度

(2)粒子在磁场中运动的轨道半径r;

(3)粒子从M点运动到P点的总时间t。

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Success________ hard work while laziness ________ failure, as everyone knows.

A.results in; results from

B.results from; results in

C.leads to; lies in

D.results in; leads to

题型:问答题 简答题

下列说法正确的是(  )

A.当氢原子从n=2的状态跃迁到n=6的状态时,发射出光子

B.放射性元素的半衰期是指大量该元素的原子核中有半数发生衰变需要的时间

C.卢瑟福在α粒子散射实验中发现了电子

D.原子弹是利用了核聚变的原理

题型:问答题 简答题

表面活性剂不具有()

A.增溶作用

B.助溶作用

C.润湿作用

D.乳化作用

E.起泡作用

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