利用太阳能电池在太阳光照射下发电叫光伏发电.安阳市启动了“光伏工程”示范项目,在

题型:计算题

问题:

利用太阳能电池在太阳光照射下发电叫光伏发电.安阳市启动了“光伏工程”示范项目,在某中学的教学楼顶安装了总功率为20kW的光伏发电系统.

(1)光伏发电系统发电时,__________能转化为_________能.

(2)一天的有效光照时间按8h计算,该光伏发电系统一天共发电多少千瓦时?

(3)该光伏发电系统一天的发电量,如果由热电转换效率为30%的热电厂来完成,需要燃烧多少千克煤?(煤的热值q=3.0×107J/kg )

(4)请写出一条光伏发电的优点.

考点:能量转移和能量转化热值电功或电能的计算有利于节约能源的措施
题型:计算题

0°经线穿过下列哪个城市?(  )

A.伦敦

B.悉尼

C.北京

D.纽约

题型:计算题

---What does your mother do to keep fit, Tom? ---She usually ______ after supper.

A.walk

B.walks

C.is walking

D.to walk

题型:计算题

I wish there would be a way to describe China in simple terms but that’s impossible. For the most part Chinese people are friendly, easy-going and optimistic. They are curious and unusually patient and they are also the hardest-working people I have ever met.

In China, family is everything. In my English classes when the students were asked what they would do if they only had a few hours to live, most students told me how they would spend their last few hours with their families and parents. Many times the subjects in the classes center on families and friends. I teach many students a year, talking to them freely.

The cost of living here is very low compared with that of the US. The city of Xiang Fan I live in isn’t large and I live better. Non-imported(非出口的) foods are very cheap, so are clothing and articles of everyday use. The cost of public transportation is very low, too. Chinese value education. However, it is reported that many children can’t afford the expenses of schooling and are forced to leave school in some poor area in China. But they organized Project Hope many years age. It creates conditions for the poor children to go back to school. In my opinion, Project Hope is of great importance to the development of the rural education.

When we read news of China in the west, rarely, if ever, will we see anything mentioned of the positive changes China has gone through. While it is true that economic miracles have not reached many areas of China, but we also have the same problems.

When I am asked which country I consider better. China or the US, my answer has always been the same, “We are not worse or better than each other, we are only different.”

小题1:What does the author think of Chinese people?

A.He thinks most Chinese people hardly work.

B.He thinks most Chinese people are proud.

C.He praises most Chinese people a lot.

D.He dislikes most Chinese people.小题2:What is the author doing in China?

A.He is visiting the places of interest.

B.He is teaching English in a school.

C.He is studying in a college.

D.He is on business.小题3:What are not cheap in China in the author’s opinion?

A.Clothes and shoes made in China.

B.Local foods

C.Public transportation tickets.

D.Imported foods小题4:We can infer from the passage that the author thinks________.

A.the westerners have got to know China well

B.China’s economic miracles have appeared everywhere

C.the progress of China is seldom reported in the US

D.the education in rural areas is never cared about in China小题5:In the author’s eyes,________.

A.China is different from the US

B.China is better than the US

C.Americans are richer than Chinese

D.China bears great similarities to the US

题型:计算题

群集服务的优点是()、修复返回、易管理性和可扩展性。

题型:计算题

下列疾病中禁用吗啡的是()

A.急性肺水肿

B.肋骨骨折

C.严重的头痛和震荡

D.晚期癌症

E.心源性哮喘

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