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标题: prep一道,百思不解 [打印本页]

作者: christy42728    时间: 2008-4-21 23:20
标题: prep一道,百思不解

 

1.    (24179-!-item-!-188;#058&000705)

 

Although fullerenes--spherical molecules made entirely of carbon--were first found in the laboratory, they have since been found in nature, formed in fissures of the rare mineral shungite.  Since laboratory synthesis of fullerenes requires distinctive conditions of temperature and pressure, this discovery should give geologists a test case for evaluating hypotheses about the state of the Earth's crust at the time these naturally occurring fullerenes were formed.(是说可以通过实验室产生的条件推回自然界产生的时间吗?)

 

Which of the following, if true, most seriously undermines the argument?

 

(A) Confirming that the shungite genuinely contained fullerenes took careful experimentation.

(B) Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft.

(C) The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed.

(D) The naturally occurring fullerenes are arranged in a previously unknown crystalline structure.

(E) Shungite itself is formed only under distinctive conditions.

答案是D


作者: 愁予    时间: 2008-4-21 23:50

化学上,化学元素相同而晶体结构不同的两种物质(比如金刚石和石墨),也就是同素异形体,被认为在物理性质上会有很大的差别。我觉得d要说的是自然环境中的f和实验室的f是同素异形体,也就不能从实验室的条件退回到自然条件中。很类似于一道类比题


[此贴子已经被作者于2008-4-21 23:52:22编辑过]

作者: christy42728    时间: 2008-4-22 22:57

up

这里的arranged in 怎么翻译?谢谢!


作者: anistonlucky    时间: 2008-4-22 23:17

there is a flaww that the author assumes the F in the nature and in the lab is comparable,so he reasons that according to the F in the lab,it is likely to help the ecoligist to evaluate the state of earth crust.

but what if both of them are not comparable,namely that the answer says their structures are different! 






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