问题 单项选择题

自总皂苷中分离甾体皂苷可选用

A.乙醚沉淀法
B.胆甾醇沉淀法
C.铅盐沉淀法
D.吉拉尔试剂提取法
E.碱水提取法

答案

参考答案:B

解析:甾体皂苷可以和胆甾醇形成不溶于水的分子复合物沉淀。

阅读理解

阅读理解。

     Microblog is a kind of multimedia blog (多媒体博客) that allows users to send messages, articles,

 photos and videos on the Internet. The information can be read by anyone or by someone that is chosen

  by the user.

     Microblog is different from a traditional blog. It is smaller in size. Like any other Internet tool,

 Microblog can be used for a number of purposes (目的).

     Microblog is a tool for communicating with your friends. We can make what happened to us known

  to our friends, anywhere and at any time, for example, "I watched the film Confucius today. It is really

  nice. "Then your friends can have a short discussion on your topic. They can also post similar events in

  their lives to share with you.

     Microblog can also offer you the chance to get closer to movie stars or sport stars. Stars can write

 what they see, hear, or think through Microblog. Fans can learn more about their favourite stars' daily

 activities immediately.

     Students can also use Microblog as a social service to see what their classmates are doing. Everyone

  finds it useful, not only students. For example, when preparing for performances, organizers can use

 Microblog to contact performers and quickly.

1. People can't send _____ online by Microblog according to the first paragraph.

    A. videos

    B. photos

    C. articles

    D. emails

2. Which of the following about Microblog is TRUE?

    A. It is smaller than a traditional blog.

    B. Only your friends can see the information on your Microblog.

    C. Every star has their own Microblog.

    D. Microblog is popular with everyone.

3. What dose the underlined word"contact"mean in Chinese?

    A. 表扬

    B. 联系

    C. 招聘

    D. 排练

4. Which of the following is the writer's opinion on Microblog?

    A. It is harmful to children.

    B. It has many advantages.

    C. Using it is very expensive.

    D. People only use it for fun.

5. What is the passage mainly about?

    A. An introduction to Microblog.

    B. How to use Microblog.

    C. The bad effects of Microblog.

    D. Who likes to use Microblog.

多项选择题