下列关于放射性现象的说法中,正确的是( ) A.原子核发生α衰变时,生成核与原来

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问题:

下列关于放射性现象的说法中,正确的是(   )

A.原子核发生α衰变时,生成核与原来的原子核相比,中子数减少了4

B.原子核发生α衰变时,生成核与α粒子的总质量等于原来的原子核的质量

C.原子核发生β衰变时,生成核的质量数比原来的原子核的质量数多1

D.单质的铀238与化合物中的铀238的半衰期是相同的

考点:原子核的组成
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关于人工流产钳夹术出血量多时的处理,不正确的是

A.及时更换不适合的吸管

B.停止操作,静滴止血药

C.尽快取出宫内胚胎组织

D.立即在宫颈注射宫缩剂

E.必要时配血输血

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清政府决定修建京张铁路,任命谁为总工程师   [ ]

A.詹天佑    

B.侯德榜    

C.严复    

D.魏源

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第二节:完形填空(共20小题;每小题1.5分,满分30分)

What is in the drug that makes you sick or dead? For example, cocaine is harmful, but what makes it harmful?

I can’t tell you all about drugs, but I can ___36___ you think about them in this ____37____ way. Your body is a very complicated machine, ____38____ a lot of chemical machinery, all of which is finally turned ____39____ it all works together. Special chemicals, which we call drugs, can affect it in many different ways.

Some drugs are ____40____ when your body has a problem, as with disease—causing bacteria. Then someone may give you aspirin to keep your temperature from going too ____41____ or some penicillin (青霉素) ____42____ it stops the growth of some kinds of bacteria. ___43_____, all drugs are really poison, ____44_____ if you take too much, so you must always use them ____45____.

Why do some people take drugs like cocaine? For a little while they seem to make you feel better, or happier. But ____46____ their effects have ____47____, your body has to pay an extra ____48____ to get back to normal. That makes you want to get ____49____ of the drug.

Drugs like cocaine have their special effects because they act as ____50____ for your nervous system. They cut off some of your nerve pathways and take away some of your senses and your ____51___. They make you want always more. And just a little too much can even ____52____ nerves to your heart and stop its beating

Many of us worry about the ____53____ around us and what pollution does to us. How about your internal environment and what goes on ____54____ you? You control that all by yourself in what you put into your ____55_____. Most drugs are pollutants. You would not want pollutants in the air and water around you. Why would you want pollutants in your body?

36.  A.   make              B.   cause                    C.  help                 D.   let

37.  A.   funny             B.   different               C.  simple              D.   true

38.  A.   just                B.   really                   C.  especially         D.   sometimes

39.  A.   as if              B    even if                 C.  where              D.   so that

40.  A.   powerful        B.   helpful                 C.  painful             D.   helpless

41.  A.   high               B.   tall                       C.  much               D.   hot

42.  A.   when              B.   until                     C.  as                    D.   before

43.  A.   besides           B.   thus                     C.  however           D.   naturally

44.  A.   at most           B.   at least                 C.  at times            D.   at first

45.  A.   carefully         B.   easily                   C.  carelessly         D.   a lot

46.  A.   where             B.   before                  C.  after                D.   until

47.  A.   worked           B.   worn                    C.  appeared          D.   lost

48.  A.   number          B.   quantity                C.  amount            D.   price

49.  A.   Some more     B.   nothing                C.  a little              D.   a few

50.  A.   guards            B.   medicine              C.  chemicals         D.   poisons

51.  A.   worries           B.   happiness              C.  freedom           D.   pride

52.  A.   lead               B.   block                   C.  offer                D.   stick

53.  A.   places             B.   nature                  C.  people              D.   environment

54.  A.   inside             B.   around                 C.  outside             D.   next

55.  A.   heart              B.   head                     C.  body                D.   mind

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乘坐飞机在起飞或降落时、或在遇到巨大声响时,最好要张开嘴或捂住耳朵.这样做主要是为了保护         

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下列建筑中,当其楼梯间的前室或合用前室采用敞开阳台时,楼梯间可不设置感烟系统的是:()。

A.建筑高度为68m的旅馆建筑

B.建筑高度为52m的生产建筑

C.建筑高度为81m的住宅建筑

D.建筑高度为52m的办公建筑

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