用雷氏铵盐溶液沉淀生物碱时,最佳条件是A.碱性水溶液 B.酸性水溶液 C.中性水溶液

题型:单项选择题

问题:

用雷氏铵盐溶液沉淀生物碱时,最佳条件是

A.碱性水溶液

B.酸性水溶液

C.中性水溶液

D.95%乙醇溶液

E.氯仿

考点:中西医结合执业助理医师中医基础理论
题型:单项选择题

名著阅读。(3分)

《水浒传》里有一百零八个好汉,他们的故事吸引着无数读者的心,其中“风雪山神庙”的是__________,“沂岭杀四虎”的是__________,“大闹野猪林”的是__________。

题型:单项选择题

阅读理解。

    When you want to go shopping, decide how much money you can, spend for new clothes.

Think about the kind of clothes you really need. Then look for those clothes on sale (销

售). There are labels (标签)inside all new clothes. The labels tell you how to take care

of your clothes. The label for a shirt may tell you to wash it in warm water. A sweater

label may tell you to wash by washing in cold water. The label on a coat may say "dry

clean only". Washing may ruin (损坏) this coat. If you do as the directions (说明) say on

the label, you can keep your clothes looking their best.

    Many clothes today must be dry cleaned. Dry cleaning is expensive. When buying new

clothes, check (核实) to see if they will need to be dry cleaned. You will save money if

you buy clothes that can be washed. You can save money if you buy clothes that are well

made. Well-made clothes last longer. They look good even after they have been washed many

times. Clothes that cost more money are not always better made. They do not always fit (合

身) better. Sometimes less expensive clothes look and fit better than more expensive

clothes.

1. If you want to save money, you can buy clothes that _____. [ ]

A. don't fit you

B. don't last long

C. need to be dry cleaned

D. can be washed

2. The labels inside the clothes tell you _____. [ ]

A. how to keep them looking their best

B. how to save money

C. whether they fit you or not

D. where to get them dry cleaned.

3. The first thing for you to do before you buy clothes is _____. [ ]

A. To look for well-made clothes

B. to see how much money you can pay

C. to know how to wash them

D. to read the labels inside them

4. We learn form the reading that cheaper clothes _____. [ ]

A. are always worse made

B. must be dry cleaned

C. can not be washed

D. can sometimes fit you better

5. The best title (标题) for the reading should be _____. [ ]

A. Buying Less Expensive Clothes

B. Taking Enough When Shopping

C. Being a Clever Clothes Shopper

D. Choosing the Labels inside New Clothes

题型:单项选择题

提取药材中的香豆素、内酯等成分时,采用的乙醇浓度一般为()

A.90%

B.70%~90%

C.50%~70%

D.40%~50%

E.20%~30%

题型:单项选择题

天体是指()

A.所有恒星

B.所有行星

C.彗星和星云

D.宇宙中存在的所有物质

题型:单项选择题

腐蚀品着火时,可用水柱直接喷射扑救。

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