问题 问答题 简答题

发动机过热的后果是什么?

答案

参考答案:

发动机过热将产生下列不良后果:

(1)气缸与进气歧管温度过高,混合气受热膨胀,充气量减少,导致发动机功率下降。

(2)发动机部件高温膨胀变形后,运动件间的正常间隙被破坏,使摩擦加剧,阻力增大,严重时会产生烧毁、卡死等现象。

(3)金属材料的力学性能降低,造成零件变形及损坏。

(4)润滑油黏度减小,造成润滑不良,加剧零件磨损。

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How to Study Smarter, Not Harder

Here are some of our favorite study tips that will help any student study smarter, not harder:

Recite As You Study

Reciting—saying things out loud should first take place as you read through each paragraph or section. Test yourself. This will help you to understand as well as learn faster because it is more active than reading or listening. It will also help you to notice your mistakes and the topics you have trouble understanding.

Take Fuller Notes

Notes should be in your own words, brief and clear. They should be tidy and easy to read. Writing notes will help you better than just underlining as you read, since it forces you to rewrite ideas in your own words.

Study the Middle

The best time to review is soon after you’ve learned something. You are more likely to remember the material at the beginning and the end of the lesson, so make sure you focus on the middle when you review.

Sleep On It

Study before going to bed, unless you are very tired. It’s easier to remember material you’ve just learned after sleeping than after an equal period of daytime activity, because your brain continues to think even after you’ve fallen asleep.

Combine Memory and Understanding

There are two ways to remember: by memorizing and by understanding. Multiplication tables, telephone numbers, and math formulas are better learned by rote. Ideas are best learned by understanding.

The more ways you have to think about an idea, the more meaning it will have; the more meaningful the learning, the better you can remember it. Pay attention to similarities in ideas and concepts, and then try to understand how they fit in with things you already know. Never be satisfied with anything less than a completely clear understanding of what you are reading. If you are not able to follow the thought, go back to the place where you first got confused and try again.

小题1: You can notice your mistakes by _______.

A.saying things out aloud

B.taking notes

C.studying the middle

D.sleeping on it小题2:When taking notes, you should _______ to better help you with reading.

A.underline important notes

B.write notes in your own words

C.take down every detail

D.write as quickly as possible小题3:The writer advises you to _______ as it is easier for you to remember material.

A.study after a period of activity

B.do some exercise after studying

C.study as soon as you get up

D.study before going to sleep小题4:Which of the following is NOT helpful for your understanding?

A.Thinking about an idea in different ways.

B.Relating ideas and concepts with what you already know.

C.Reading from the beginning to the end without stop.

D.Going back to what first made you confused and start again.