什么是车轴荷重?

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问题:

什么是车轴荷重?

考点:车辆钳工考试中级车辆钳工考试中级车辆钳工考试题库
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You’re on the school bus. But as soon as you turn the corner, you find yourself at the end of a very long queue. It’s another traffic jam! It is stop-start for the rest of your journey. Meanwhile, at the same time in Antarctica(南极洲), snow covers the land. A group of emperor penguins crowd together to keep warm, using stop-and-go movements to protect themselves from the winds. Can you see the connection?

Emperor penguins move like cars in traffic jams to keep warm, that’s according to new research by the Alfred Wegener Institute, Helmholtz Center for Polar and Marina Research in Germany. A penguin only needs to move 2cm in any direction for its neighbor to do the same thing. These movements then flow(流动) through the whole group of penguins like a “traveling wave”.

These waves also help smaller crowds join bigger groups, keeping more and more of their friends warm. A single Antarctic “traffic jam” has thousands of penguins. Interestingly, the technology used for studying road traffic jams was used to study the penguins. This included studying time-lapse(延时) videos. Scientists also discovered that unlike on the road, these waves can be made by any penguin and in any direction.

With temperatures usually dropping below –50℃, and winds reaching speeds of up to 200km/h, these traveling waves are very important for penguins to keep warm.

These penguins can also teach us a lesson. In big groups, they learn to be orderly and patient, and to never crash into each other. These are skills we should all learn from them when we are on the road!

小题1:Emperor penguins get together to _____.

A.keep warm

B.play games

C.learn from each other

D.cross the road小题2:In a traffic jam on the road, __________.

A.drivers can drive fast

B.drivers can drive carelessly

C.cars are not moving fast

D.cars will stop working小题3:From the passage, we learn that a “traveling wave” _____.

A.is caused by a traffic jam on the road

B.is caused by the strong wind in Antarctica

C.is formed by the movement of the penguins

D.is made by just one or two penguins小题4:If a penguin is in a group, it _____.

A.needs to move orderly

B.can move as fast as it likes

C.will not leave others behind

D.should move as slowly as it can小题5:The last paragraph wants to tell us that _____.

A.penguins won’t move together if it is not very cold

B.traffic jams happen probably because people are impatient

C.penguins learn their skills from human beings

D.penguins are likely to crash into each other in a group

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以R134a为制冷剂的制冷装置压力容器进行液压试验时,最合适的试验介质是()。

A.矿物油

B.水

C.酯类油

D.醚类油

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男性,19岁。上腹间歇性隐痛1年,时有反酸,胃液分析示BAO/MAO<0.6,MAO42mmol/h。诊断为()

A.十二指肠溃疡

B.急性糜烂性胃炎

C.胃良性溃疡

D.胃淋巴瘤

E.胃泌素瘤

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对市场调研方案在技术上的科学性和适用性的研究是()。

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喷射泵内运动零部件的润滑材料为()。

A.燃油

B.机油

C.柴油蒸气

D.润滑脂

E.石蜡

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