When Dr. John W. Gofman, professor of medi

题型:单项选择题

问题:

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

考点:普通考研中医综合中医综合
题型:单项选择题

如图,ABD为竖直平面内的光滑绝缘轨道,其中AB段是水平的,BD段为半径R=0.2m的半圆,两段轨道相切于B点,整个轨道处在竖直向下的匀强电场中,场强大小E=5×103N/C,一不带电的绝缘小球甲,以初速度V0沿水平轨道向右运动,到B点时与静止在该点带正电的小球乙发生弹性碰撞,碰撞后乙球恰能通过轨道的最高点已知甲、乙两球的质量均为m=1xlO-2kg,乙球所带电荷量q=2×10-5C(取g=10m/S2,水平轨道足够长,甲、乙两球可视为质点,整个运动过程无电荷转移)求:

(1)乙球通过D点后落到水平轨道上的位置距B点的距离;

(2)甲球初速度V0的大小.

题型:单项选择题

 Текст(3)  Павла Михайловича Третьякова едва ли можно назвать коллекционером (21. привычный смысл). Посвятив жизнь (22. собирание) живописи, отдав этому делу вес силы и средства - от начальной покупки (23. картины) до создания здания галереи, -он поступил не как одиночка-искатель, а как создатель общенародной коллекции живописи.  Многие знаменитые русские художники продавали свои работы Третьякову, а не другим. (24. понимать), что значит его коллекция.  Первые русские картины Павел Третьяков купил в 1856 г. , этот гад он считал (25. дата) основания галереи. Сначала картины висели в доме, где жили Третья коны, но постепенно стали строить новые залы, (26. предназначить) для показа живописи. В дальнейшем все (27. часто и часто) собрание Павла Третьякова стали называть "Третьяковская галерея". И в галерее появился зал, (28. занять) портретам и, (29. написать) старыми мастерами. В 1941 г. сокровища галереи (30. отправить) в Сибирь, а в 1944 г. снова вернулись в Москву. И сейчас здесь всегда многолюдно. Третьяковская галерея - одно из лучших украшений художественной Москвы.

题型:单项选择题

下列选项中,不属于金融衍生品市场的是()。

A.期货市场

B.基金市场

C.互换市场

D.远期协议市场

题型:单项选择题

进行健康教育与健康促进干预时,采用哪种策略效果将会更好()

A.社会策略

B.环境策略

C.教育策略

D.资源策略

E.综合策略

题型:单项选择题

信息加工的基本原则有()。

A.标准性原则

B.系统性原则

C.准确性原则

D.及时性原则

E.通俗性原则

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