下列哪一项为1牛顿的力均匀而垂直地作用在1平方米平面上所产生压力之单位名称() A

题型:单项选择题

问题:

下列哪一项为1牛顿的力均匀而垂直地作用在1平方米平面上所产生压力之单位名称()

 

A.1大气压

B.1Pa

C.1psi

D.1mmHg

考点:中医针灸(医学高级)金匮要略金匮要略题库
题型:单项选择题
计算:(
1
16
 -
1
2
+(-
2
3
0-
32
+log39.
题型:单项选择题

某小儿体重为15kg,A药物的成人剂量为每日2g,B药物的小儿剂量为每日每公斤体重40mg。

该小儿A药物的剂量为()

A.每日300mg

B.每日400mg

C.每日500mg

D.每日600mg

E.每日700mg

题型:单项选择题

Sometimes, the simplest ideas are the best. For example, to absorb heat from the sun to heat water, you need large, flat, black surfaces. One way to do that is to build those surfaces specially, on the roofs of buildings. But why go to all that trouble when cities are full of black surfaces already, in the form of asphalt (柏油) roads?

Ten years ago, this thought came into the mind of Arian de Bondt, a Dutch engineer. He finally persuaded his boss to follow it up. The result is that their building is now heated in winter and cooled in summer by a system that relies on the surface of the road outside.

The heat-collector is a system of connected water pipes. Most of them ran from one side of the street to the other, just under the asphalt road. Some, however, dive deep into the ground.

When the street surface gets hot in summer, water pumped through the pipes picks up this heat and takes it underground through one of the diving pipes. At a depth of 100 metres lies a natural aquifer (蓄水层) into which several heat exchangers (交换器) have been built. The hot water from the street runs through these exchangers, warning the ground-water, before returning to the surface through another pipe. The aquifer is thus used as a heat store.

In winter, the working system is changed slightly. Water is pumped through the heat exchangers to pick up the heat stored during summer. This water goes into the building and is used to warm the place up. After performing that task, it is pumped under the asphalt and its remaining heat keeps the road free of snow and ice.

小题1:Which of the following is true according to the first two paragraphs?  

A.Arian de Bondt got his idea from his boss.

B.Large, flat, black surfaces need to be built in cities.

C.The Dutch engineer’s system has been widely used.

D.Heat can also be collected from asphalt roads.小题2:For what purpose are the diving pipes used?  

A.To absorb heat from the sun.

B.To store heat for future use.

C.To turn solar energy into heat energy.

D.To carry heat down below the surface.小题3:From the last paragraph we can learn that __ 

A.some pipes have to be re-arranged in winter

B.the system can do more than warming up the building

C.the exchangers will pick up heat from the street surface

D.less heat may be collected in winter than in summer小题4:What is most likely to be discussed in the paragraph that follows?  

A.What we shall do if the system goes wrong.

B.What we shall do if there are no asphalt roads.

C.How the system cools the building in summer.

D.How the system collects heat in spring and autumn

题型:单项选择题

人类历史上最早带领船队完成环球航行的航海家是().

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耳蜗毛细胞去极化感受器电位的产生机制是()

A.K+经机械门控通道内流增加

B.Na+经机械门控通道内流增加

C.Ca2+经机械门控通道内流增加

D.Ca2+经电压门控通道内流增加

E.Na+经电压门控通道内流增加

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