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问题 填空题

据报道，太阳能光伏发电在上海世博会上得到了大规模的应用，总装机容量超过4.68兆瓦。

（1）发展太阳能产业主要优点是（填一点即可）___________________。

（2）太阳能光伏发电最关键的材料是高纯硅，下图是我市某多晶硅生产企业生产高纯硅的流程示意图：

发生的反应为：①SiO2+2CSi+2CO↑；②Si+3HClSiHCl3+H2↑；③SiHCl3+H2Si+3HCl。整个制备过程必须达到无水无氧。在H2还原SiHCl3过程中若混入O2，可能引起的后果是________________。

（3）为了达到绿色化学和节约资源的目的，上述流程中某化合物需要循环使用，该物质的化学式是________。

答案

（1）无污染（利于环保、减少碳排放、减少化石能源消耗等）

（2）爆炸

（3）HCl（或H2）

阅读理解

"Make-A-Wish” is one of the world's most well-known charities(慈善机构) . It makes wishes come true for childrenwho have serious illnesses. It gives them hope and joy and helps them forget about their health problems and have fun.

It all started in 1980 in Phoenix, Arizona. Christopher was a 7-year-old boy who was very sick. He always dreamed ofbecoming a police officer. Tommy Austin and Ron Cox, two police officers, made his wish come true. They gaveChristopher a tour of the city in a police helicopter(直升飞机)and made a real police uniform(制服) for him.

There are four kinds of wishes children usually have:

I wish to go. Children usually want to travel or go to a concert, a game or a park.

I wish to meet. Children sometimes want to meet their favourite actors, singers or players.

I wish to be. Some children wish to become actors, singers or police officers.

I wish to have. They often want to have a computer, a game, a bike or many other things.

Let’shope more wishes Mill come true in the future. People who work in the charity always try for the best. Almost25 ,000 Volunteers (志愿者) help, work or give money. Will you be one of them?

小题1:"Make-A-Wish" is a charity to help _______.

A．sick children

B．serious officers

C．famous actors

D．popular singers小题2:What did the two police officers do for Christopher?

A．They gave him a computer.

B．They gave him a tour of the city.

C．They look him to a concert.

D．They took him to the hospital.小题3:Which kind of wishes does Christopher have?

A．I wish to go.

B．I wish to meet.

C．I wish to be.

D．I wish to have.小题4:The purpose of the last paragraph is to _______.

A．explain what " Make-A-Wish" is

B．encourage more people to join the charity

C．tell us how Christopher's wish came true

D．introduce different kinds of children's wishes小题5:Which of the following is TRUE according to the passage?

A．Sick children just wish to get well.

B．Christopher and Tommy are two officers.

C．A few people are working for "Make-A-Wish".

D．"Make-A-Wish" has a history of over 30 years.
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填空题

有一两级除尘系统，两级除尘器粉尘通过率分别为20%和10%，则该除尘系统的总除尘效率为（）。
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