问题 单项选择题

利用溶剂萃取法从中药的水提液中提取苷类成分常用的溶剂是()

A.乙醇

B.甲醇

C.丙酮

D.乙醚

E.正丁醇

答案

参考答案:E

解析:本题考查溶剂的极性大小及苷类成分的萃取方法。溶剂萃取法的前提是两相溶剂互补相溶,本题中答案A、B、C均能与水互溶,故排除。答案D中乙醚为亲脂性有机溶剂,常用来萃取极性较小的化学成分。苷类成分最常用的萃取溶剂为正丁醇,故正确答案为E。

完形填空

Section B (10points)

Directions: Read the following passage. Answer the questions according to the information given in the passage and required words limit.

The word addiction(上瘾) usually makes you think of alcohol or drugs(酒精或毒品), but in modern society we are seeing some new kinds of addictions. Some people are compulsive(难以自制的)shopper. Others find it impossible to keep themselves away from their work. Still others spend many hours watching TV or playing computer games.

Over the years, shopping has become a very common activity. Many people enjoy going to the stores more and more every day. They have turned into shopaholics. They are people who simply enjoy shopping and walking around spending money without being able to stop doing it. They are crazy about shopping and usually buy things that they don’t need. Even though they don’t have enough money, they buy everything they want.

The question is: why do they have this addiction? There isn’t a good answer. Some people go shopping when they are sad, worried, upset or lonely and they want to feel better. They use this activity as a way to forget their problems. Shopaholics say they feel more important and better after they buy something. They also tend to have this activity when they feel guilty(负罪感的).

Shopaholism seems to be a harmless addiction, but it can cause many problems. People addicted to shopping should go to a support group to help them break this habit.

81. List three activities that might develop into addictions based on the text. (within 8 words)

_________________________________________________________________________

82. Can experts (专家) exactly explain why people are addicted to shopping? (within 3 words)

_________________________________________________________________________

83. What should the people addicted to shopping do according to the passage? ( within 9 words)

_________________________________________________________________________

84. Translate the underlined sentence in Paragraph 2 into Chinese.

_________________________________________________________________________

计算题