下图所示为实验室中完成不同的化学实验所选用的装置或进行的操作,其中没有明显错误的

题型:选择题

问题:

下图所示为实验室中完成不同的化学实验所选用的装置或进行的操作,其中没有明显错误的是         ( )

考点:化学实验的基本操作化学实验安全危险化学品的标志化学药品的变质
题型:选择题

关于子痫,正确的是()

A.抽搐发生前多出现头痛、头晕眼花、恶心等先兆子痫的症状

B.子痫不会发生在分娩过程中

C.分娩后不会再发生子痫

D.子痫不会对母儿造成严重危害

E.子痫患者除抽搐外、不会发生肾衰等其他并发症

题型:选择题
对于函数f(x),若存在x0∈R,使f(x0)=x0成立,则称x0为f(x)的不动点.如果函数f(x)=
x2+a
bx-c
(b,c∈N)
有且只有两个不动点0,2,且f(-2)<-
1
2

(1)求函数f(x)的解析式;
(2)已知各项不为零的数列{an}满足4Sn•f(
1
an
)=1
,求数列通项an
(3)如果数列{an}满足an=f(an),求证:当n≥2时,恒有an<3成立.
题型:选择题

高热,咳吐脓血腥臭痰者属于()

A.痰热阻肺证

B.热邪壅肺证

C.风热犯肺证

D.肺阴虚证

E.燥邪犯肺

题型:选择题

苏格拉底提出“美德即知识”并提出美德一定要践行,孔子提出“礼”与“仁”的道德规范。其共同点是()

A.重视智慧发展

B.关注理性思考

C.强调道德素养

D.强调等级秩序

题型:选择题

When Dr. John W. Gofman, professor of medical physics at the University of California and a leading nuclear critic, speaks of "ecocide" in his adversary view of nuclear technology, he means the following. A large nuclear plant like that in Kalkar, the Netherlands, would produce about 200 pounds of plutonium each year. One pound, released into the atmosphere, could cause 9 billion cases of lung cancer. This waste product must be stored for 500,000 years before it is of no further danger to man. In the anticipated reactor economy, it is estimated that there will be 10,000 tons of this material in Western Europe, of which one table-spoonful of plutonium-239 represents the official maximum permissible body burden for 200,000 people. Rather than being biodegradable, plutonium destroys biological properties.

In 1972 the .U.S. Occupational Safety and Health Administration ruled that the asbestos level in the work place should be lowered to 2 fibers per cubic centimeter of air, but the effective date of the ruling has been delayed until now. The International Federation of Chemical and General Workers’ Unions report that the 2-fiber standard was based primarily on one study of 290 men at a British asbestos factory. But when the workers at the British factory had been reexamined by another physician, 40--70 percent had X-ray evidence of lung abnormalities. According to present medical information at the factory in question, out of a total of 29 deaths thus far, seven were caused by lung cancer. An average European or American worker comes into contact with six million fibers a day. "We are now, in fact, finding cancer deaths within the family of the asbestos worker," states Dr. Irving Selikoff, of the Mount Sinai Medical School in New York.

It is now also clear that vinyl chloride, a gas from which the most widely used plastics are made, causes a fatal cancer of the blood-vessel cells of the liver. However, the history of the research on vinyl chloride is, in some ways, more disturbing than the "Watergate cover- up. " "There has been evidence of potentially serious disease among polyvinyl chloride workers for 25 years that has been incompletely appreciated and inadequately approached by medical scientists and by regulatory authorities," summed up Dr. Selikoff in the New Scientist. At least 17 workers have been killed by vinyl chloride because research over the past 25 years was not followed up. And for over 10 years, workers have been exposed to concentrations of vinyl chloride 10 times the "safe limit" imposed by Dow Chemical Company.

According to the text, the author mentions plutonium in paragraph 1 to()

A. estimate the amount of nuclear material in Europe

B. exemplify one of the possible causes of lung cancer

C. highlight the measures needed to prevent lung cancer

D. show the destructive properties of industrial waste materials

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