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问题 问答题

“纳米材料”是指微粒直径为几纳米到几十纳米的材料．如将纳米材料分散到水中，得到的分散系不可能具有的性质是下列的（　　）

A．能全部透过半透膜

B．能全部通过滤纸

C．有丁达尔效应

D．有布朗运动

答案

因纳米碳分子分散到水中，所形成的分散系为胶体分散系，

A、胶体粒子的直径大于溶液中分散质粒子的直径，则纳米材料不能透过半透膜，故A选；

B、溶液和胶体分散系中粒子的直径都比滤纸中小孔直径小，则能全部透过滤纸，故B不选；

C、因形成的是胶体分散系，则具有丁达尔效应，故C不选；

D、因形成的是胶体分散系，则有布朗运动，故D不选．

故选A．

阅读理解与欣赏

阅读下列文字，按要求翻译句子

文帝之后六年，匈奴大入边。乃以宗正刘礼为 * * ，军霸上；祝兹侯徐厉为 * * ，军棘门；以河内守亚夫为 * * ，军细柳，以备胡。

上自劳军。至霸上及棘门军，直驰入，将以下骑送迎。已而之细柳军，军士吏被甲，锐兵刃，彀弓弩，持满。天子先驱至，不得入。先驱曰：“天子且至!”军门都尉曰：“ * * 令曰‘军中闻 * * 令，不闻天子之诏’。”居无何，上至，又不得入。于是上乃使使持节诏 * * ：“吾欲入劳军。”亚太乃传言开壁门。壁门士吏谓从属车骑曰：“ * * 约，军中不得驱驰。”于是天子乃按辔徐行。至营， * * 亚夫持兵揖曰：“介胄之士不拜，请以军礼见。”天子为动，改容式车。使人称谢：“皇帝敬劳 * * 。”成礼而去。既出军，群臣皆惊。文帝曰：“嗟乎，此真 * * 矣!曩者霸上、棘门军，若儿戏耳，其将固可袭而虏也。至于亚夫，可得而犯邪!”   

称善者久之。月余，三军皆罢。乃拜亚夫为中尉。

孝文且崩时，诫太子曰：“即有缓急，周亚夫真可任将兵。”文帝崩，拜亚夫为车骑 * * 。(《史记·绛侯世家》)

翻译：即有缓急，周亚失真可任将兵。 

[译文]____________________________________________________________________
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Part 2


Questions 9-18


·Read the following passage and answer questions 9-18.
1. When Christopher Columbus landed on America’s shores, he encountered copper-shinned people whom he promptly called "Indians". Current estimates indicate that there were over a million Indians inhabiting North American then. There are approximately 800,000 Indians today, of whom about 250, 000 live on reservations.
2. The early settlers had an amicable relationship with Indians, who shared their knowledge about hunting, fishing, and farming with their uninvited guests. The stereotyped stealthy, wicked Indian of western movies are created by different faithless white man; the Indian was born friendly.
3. Disgust developed between the Indians and the settlers, whose encroachment on Indian lands provoked an era of turbulence. As early as 1745, Indian tribes joined together to drive the French off their land. The French and Indian war did not end until 1763. The Indian had succeeded in destroying most of the settlements. The British, superficially submissive to the Indiana, promised that further migrations west would not extend beyond a specified boundary.
4. Vacated from their lands or, worse still, frankly giving their property to the whites for few baubles, Indians were ruthlessly pushed west. The battle in 1876 at Little Horn river in Montana, in which setting Bull and the Sioux tribes massacred General Custer’s cavalry, caused the whites intensify their campaign against the Redman. The battle at Wound Knee, South Dakota, in 1890 put an end to the last vestige of hope for amity between Indians and whites.
5. Although the Bureau of lndian affairs has operated since 1842, presumably for the purpose of guarding Indians "interests", Indian on reservations lead notoriously deprived lives. In recent times Indians have taken a militant stand and appealed to the courts and the American people to improve their substandard living conditions.

Questions 9-13


·For questions 9-13, choose the best title for each paragraph from below.
·For each numberedparagraph (1-5), mark one letter (A-G) on the Answer Sheet.
·Do not mark any letter twice.
9. Paragraph 1: ______
  • A. Indians, once the master of America, now live in their
    reservation.
    10. Paragraph 2: ______
  • B. Indians were pushed away.
    11. Paragraph 3: ______
  • C. The wars between Indian and the settlers.
    12. Paragraph 4: ______
  • D. Indians arestill fighting for the improvement of their lives.
    13. Paragraph 5: ______
  • E. The relationship between Indians and the early settlers.
  • F. Indians were ferocious savages.
  • G. Indian’s struggle for their own possessions.
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