跪求一篇关于节能减排的英语作文,要求用初三程度,80词左右 有的快发,回得快些,

跪求一篇关于节能减排的英语作文,要求用初三程度,80词左右 有的快发,回得快些,
跪求一篇关于节能减排的英语作文,要求用初三程度,80词左右 有的快发,回得快些,

跪求一篇关于节能减排的英语作文,要求用初三程度,80词左右 有的快发,回得快些,
health,surrounded by,smog,anything but,gases,impurities,absorb,poisonous,try hard,blacked out
We all know that clean air is important to good health.Wherever you go and whatever you do,you are always surrounded by a sea of gases that we call air.If there are impurities in the air,they may be absorbed by our bodies and make us ill.We need clean air,but unfortunately,air pollution is globally present,especially in cities.
Many large cities are anything but pollution-free.Our cities have many factories,which we need to make food,clothing and other things.Every year these factories pour millions upon millions of tons of smog into air.Power plants and houses that burn coal add greatly to air pollution.Besides,there are more cars in cities now.Once out on the streets,they will take in fresh air and replace it with poisonous gases.
Our country is trying hard to prevent and control air pollution.As long as every citizen also realizes its importance and makes join efforts,the day will come soon when people will take in only clean air.Then,the sunlight will no longer be blackened out by smoke and soot.

Dear fellow students,
Our government is aiming to build a “conservation-oriented society” (节约型社会). I think it is every citizen’s duty to achieve this goal.
As high students, what s...

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Dear fellow students,
Our government is aiming to build a “conservation-oriented society” (节约型社会). I think it is every citizen’s duty to achieve this goal.
As high students, what should we do?
We should focus our attention on details around ourselves. We should form the habit
of saving water, especially when we brush our teeth and wash hands, and never leave
water running unnecessarily. Meanwhile, we ought to save electricity. When we leave
classrooms or our homes we should make sure that the light and some electrical
equipments have been turned off. Do never make the light on in the daytime if unnecessary.
We should also save our every piece of paper as well as other writing materials. What’s more, we should offer to recommend our relatives and friends as well as our parents to
save energy.
Dear fellow students, let’s start right now, and spare no effort to do every little bit from every detail on!
Wang Ming
From Shaanxi High School

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Abstract
The wear behavior of polytetrafluoroethylene (PTFE) and polyimide ( PI) has been comparatively evaluated under dry sliding and simulated sand-dust conditions. An improved block-on-ring w...

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Abstract
The wear behavior of polytetrafluoroethylene (PTFE) and polyimide ( PI) has been comparatively evaluated under dry sliding and simulated sand-dust conditions. An improved block-on-ring wear tester equipped with an attachment for simulating the sand-dust environment was used to evaluate the abrasive wear behavior of materials. The sand collected from the Yellow River of China was used to simulate the sand-dust environment, also different loads and sand-dust sizes were chosen for tribological tests. The two chosen polymers showed different wear behavior under sand-dust conditions and the wear rates of PTFE were much lower under sand-dust conditions than under dry sliding conditions. This was attributed to the formation of the tribolayer on the worn surfaces during the abrasive wear process. The sand-dust enhanced the wear resistance of PTFE, but reduced that of PI because, in contrast to PTFE, there was no tribolayer formed on the PI worn surface. The wear rate of PTFE increased under sand-dust conditions while the wear rate of PI decreased with the increase of applied load. The higher hardness of PI and fragmentation of abrasive particles under high loads accounted for the decrease in wear rate as load increased.
Keywords: PTFE; PI ; Simulated sand-dust; Tribolayer

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