内燃机一个工作循环有吸气、压缩、做功、排气四个冲程,实现将内能转化为机械能的是

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问题:

内燃机一个工作循环有吸气、压缩、做功、排气四个冲程,实现将内能转化为机械能的是 ________ 冲程。发动机运行前必须加润滑油,是为了_________________。某品牌汽车100km耗油7kg,这些汽油完全燃烧要放出__________J的热量。(汽油的热值q=4.6×107J/kg)

考点:热值内燃机的四个冲程增大或减小摩擦的方法
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J.Martin倡导的战略数据规划方法的实现往往采用自顶向下规划和 【18】 设计。

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关于先兆子宫破裂的临床表现,下列哪些正确

A.临产后强有力的宫缩可使病理性缩复环上移

B.产妇可自述下腹剧痛难忍

C.可出现排尿困难、血尿

D.胎心率可听不清

E.子宫破裂部位与病理性缩复环关系不大

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In 1879, a group of explorers made an incredible find. They discovered paintings of remarkable beauty on the walls of a cave in Spain. Some scientists believed that these paintings were created by early humans from the Stone Age, between ten and thirty thousand years ago. Other scientists and the public did not believe the claim, but over the years, it was proven correct. Our ancestors had incredible artistic talents.

Most of the cave art that has been discovered has been found in Spain and France. A smaller number of such caves are located in Italy, Portugal, Russia, and other countries. Scientists believe that many more caves will be discovered in the coming years, and are concentrating their efforts on Africa and the area between Europe and Asia. These two regions of the world were, populated first by humans.

Cave art was carved or painted on the walls and roofs of caves, usually near the entrance. The entrance area was probably chosen to take advantage of daylight and to allow many people to view the paintings. In some cases, the art appears much deeper in caves and requires artificial light. Evidence suggests that the artists used torches or shallow bowls in which animal fat was burned.

9.What was the response of general public to the discovery of cave art made by Stone Age people?

A. They believed it at first.

B. They did not believe it.

C. They thought it was beautiful.

D. They ignored it.

10.According to the passage, what can we conclude about animal fat?

A. It does not burn.

B. Stone Age artists used it to preserve their paintings.

C. It can be burned to produce light.

D. Stone Age artists mixed it with their food.

11.. Where do scientists expect to find more cave paintings?

A. In Central and South America.

B. In Spain and France.

C. In the places where there are caves with large openings.

D. In the regions of the world first populated by humans.

12.Where would this passage be most likely to appear?

A. In a textbook about early human history.

B. In a textbook about modern art.

C. In a dictionary.

D. In an encyclopedia entry about caves.

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我国义务教育阶段的中小学校实行的是()。

A.校长负责制 

B.集体负责制 

C.党委领导下的校长负责制 

D.党委领导下的集体负责制

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()是一种习惯叫法,是安装在现场、能直观的看到液位的仪表,不具有信号远传功能,供巡检时检查或者与DCS比对用。

A、液位变送器

B、液位计

C、液位控制器

D、就地液位计

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