土颗粒分析试验，（）法适用于颗粒小于等于60mm，大于0.074mm的土。A、筛分析

发布时间：2017-05-15 15:05 │ 来源：www.tikuol.com

题型：单项选择题

问题：

土颗粒分析试验，（）法适用于颗粒小于等于60mm，大于0.074mm的土。

A、筛分析法

B、密度计法

C、移液管法

考点：土工试验工土工试验工题库

题型：单项选择题

阅读理解。

        We have known for a long time that flowers of different plants open and close at different time of day.
This is so familiar that there seems to be no need to ask the reason for it. Yet no one really understands why
flowers open and close like this at particular times. The process (过程) is not as simple as we might think, as
recent experiments have shown. In one study, flowers were kept in constant (连续的) darkness. We might
expect that the flowers, without any information about the time of day, did not open as they normally do. In
fact, they continued to open at their usual time. This suggests that they have some mysterious (神秘的) way
of knowing the time. Their sense of time does not depend on information from the outside world; it is, so to
speak, inside them, a kind of "inner clock".
         This discovery (发现) may not seem to be very important. However, it was later found that not just
plants but also animals -including man -have this "inner clock" which controls the working of their bodies and
influences (影响) their activities. Men, then, are also influenced by this mysterious power. Whether we wish
it or not, it affects such things in our life as our need for sleep, our need for food.
         In the past, this did not matter very much because people lived in natural condition. In the modern
world, things are different; now there are spacemen, airplane pilots and, in ordinary life, a lot of people who
have to work at night. It would be very useful, then, to know more about the "inner clock". Such ordinary
things as flowers might help us understand more about ourselves.

1. A recent experiment showed that _______.

A. different flowers open and close at different times of day
B. for their opening and closing, flowers do not need information from the outside world
C. flowers are influenced by weak light even when they are in a dark room
D. flowers can be used for telling the time

2. The "inner clock" _______.

A. is an unimportant discovery
B. is only found in animals
C. has not been understood by far
D. has an effect on human life

3. Further study of the "inner clock" will be useful because .

A. it might help us in some way
B. we do not yet understand plants and animals well enough
C. the number of spacemen and airplane pilots is fast increasing
D. we should try to live more naturally than we do now

4. Kept in constant darkness, flowers _______.

A. will not open or close as usua
B. will not open any longer
C. will open as they do in natural conditions
D. will always remain in full blossom (开花)

5. ______ have a mysterious power of knowing time without information from the outside world.

A. Animals including man as well as plants
B. All living things except man
C. Flowers are the only things in the world that
D. Neither animals nor plants

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题型：单项选择题

"材料成本差异"科目在期末的借方余额反映的是（）。

A.库存材料的超支差异

B.库存材料的节约差异

C.发出材料应负担的超支差异

D.发出材料应负担的节约差异

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治疗心室纤颤的最有效措施是（）

A.吸氧

B.镇静

C.静注利多卡因

D.气管内滴注肾上腺素

E.电除颤

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盆栽果树“六合一”叶面施肥技术具体指什么？

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下图为DNA片段示意图，请据图回答：

有一对氢键连接的脱氧核苷酸，已查明它的结构有1个腺嘌呤，则它的其他组成应是（）

A.3个磷酸、3个脱氧核糖和1个胸腺嘧啶

B.2个磷酸、2个脱氧核糖和1个胞嘧啶

C.2个磷酸、2个脱氧核糖和1个胸腺嘧啶

D.2个磷酸、2个脱氧核糖和一个尿嘧啶

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