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问题 选择题

以下对粒子结构或性质的叙述正确的是（   ）

A．两种微粒，若核外电子排布完全相同，则化学性质一定相同

B．由单原子形成的离子，一定具有稀有气体元素原子核外电子排布

C．阴离子的核外电子排布一定与上一周期稀有气体原子核外排布相同

D．两原子，如果核外电子排布相同，则一定属于同一种元素

答案

答案：D

题目分析：A． 两种微粒，若核外电子排布完全相同，原子核内的质子不一定相同，所以化学性质不一定相同。错误。B．由单原子形成的离子，不一定具有稀有气体元素原子核外电子排布。如H+核外无电子。C．阴离子的核外电子排布不一定与上一周期稀有气体原子核外排布相同。如H-与同一周期稀有气体原子核外排布相同。错误。D． 两原子，如果核外电子排布相同，核内质子数也相同。则一定属于同一种元素。正确。

单项选择题

There is no question that the academic enterprise has become increasingly global, particularly in the sciences. Nearly three million students now study outside their home countriesa 57% increase in the last decade. Foreign students now dominate many U.S. doctoral programs, accounting for 64% of Ph. D. s in computer science, for example.
Faculty members are on the move, too. Half of the world’s top physicists no longer work in their native countries. And major institutions such as New York University are creating branch campuses in the Middle East and Asia. There are now 162 satellite campuses worldwide, an increase of 43% in just the past three years.
At the same time, growing numbers of traditional source countries for students from South Korea to Saudi Arabia (沙特阿拉伯), are trying to improve both the quantity and quality of their own degrees, engaging in a fierceand expensiverace to recruit students and create world-class research universities of their own.
Such competition has led to considerable hand-wringing in the West. During a 2008 campaign stop, for instance, then—candidate Barack Obama expressed alarm about the threat that such academic competition poses to U. S. competitiveness. Such concerns are not limited to the United States. In some countries, worries about educational competition and brain drains have led to academic protectionism. India, for instance, places legal and bureaucratic barriers in front of Western universities that want to set up satellite campuses to enroll local students.
Perhaps some of the anxiety over the new global academic enterprise is understandable, particularly in a period of massive economic uncertainty. But educational protectionism is as big a mistake as trade protectionism is. The globalization of higher education should be embraced, not fearedincluding in the United States. There is every reason to believe that the worldwide competition for human talent, the race to produce innovative research, the push to extend university campuses to multiple countries, and the rush to train talented graduates who can strengthen increasingly knowledge-based economies will be good for the United States, as well.

The word "hand-wringing" (Para. 4) probably means "______"

A. anger
B. worries
C. interests
D. delight
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单项选择题 共用题干题

患者，男性，20岁。鼻衄，伴见齿衄，出血鲜红，口渴欲饮，口干臭秽，大便秘结，舌质红，苔黄，脉数。

其证候是（）

A.热邪犯肺

B.胃热炽盛

C.肝火上炎

D.血热妄行

E.阴虚火旺
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