试题与答案

产生MClAfferty重排的先决条件是()。A、分子中有γ-H存在B、Cα一Cβ键

题型:单项选择题

题目:

产生MClAfferty重排的先决条件是()。

A、分子中有γ-H存在

B、Cα一Cβ键易断裂

C、Cβ-Cγ键易断裂

D、能形成稳定的环状中间体

答案:

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参考答案:A, B, C, D解析:《药品经营质量管理规范》第九十六条:出库时应当对照销售记录进行复核。发现以下情况不得出库,并报告质量管理部门处理:(一)药品包装出现破损、污染、封口不牢、衬垫不实、封条...

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题型:阅读理解

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    Popular breakfast foods in the United States, as in many other countries around the world, include coffee,

milk, juice, eggs and bread. Some other breakfast items served in the United States are thought by many to be

traditionally American. However, they actually come from other countries.

    A very popular breakfast food in America is the pancake---a thin, flat cake made out of flour and often served

with maple syrup. The idea of the pancake is very old. In fact, pancakes were made long ago in ancient China.

    Bagels, a round thick bread with a hole in the middle, are also popular for breakfast in America. Polish people

in the late 1600s came up with the idea for the first bagels and this new kind of bread soon took off across

Eastern Europe.

    In the late 1800s, thousands of Jews from Eastern Europe traveled to the United States and brought the

recipe for bagels with them. Today, New York bagels are said to be the best in the world. Many people have

them with cream cheese for breakfast on the go.

    Doughnuts (usually spelled "donut" in the United States) came from France. They were served to American

soldiers in France during World WarⅠ(第一次世界大战). After the war, American soldiers asked cooks in the

United States to make doughnuts for them. Now, served with coffee, they are a very popular breakfast food

across the United States.

1. This reading is mainly about _______. [ ]

A. famous places in the United States to eat breakfast

B. popular American breakfast foods coming from China

C. the most popular types of pancakes in the United States

D. the history of popular breakfast foods in the United States

2. Which of the following is true for both bagels and donuts? [ ]

A. They both came from Europe.

B. They are both easy to make.

C. They are both sweet.

D. People in New York make them best.

3. Who brought bagels to America? [ ]

A. Polish people.

B. Jewish people.

C. Chinese people

D. American soldiers.

4. Which of the following is true about doughnuts? [ ]

A. It was first made by the French.

B. The soldiers invented them in World War I.

C. Only soldiers eat them in the Untied States.

D. It is round with a hole in the middle.

5. This passage tells us that ________. [ ]

A. the Americans like to eat sweet foods for breakfast

B. all American foods come from other countries

C. not all American foods are really American

D. very few Americans have breakfast every day

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