杭州人工降雨2017

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篇一:[杭州人工降雨2017]2017年12月英语四级阅读习题：人工降雨

四六级考试网权威发布2017年12月英语四级阅读习题：人工降雨，更多2017年12月英语四级阅读习题相关信息请访问大学英语四六级考试网。
【导语】多做英语四级阅读可以让你在做阅读理解的过程中，掌握正确的阅读方法和阅读技巧，阅读速度大大提升。为了让大家能更好的备考，特别整理了2017年12月英语四级阅读习题：人工降雨，详情如下：　

Rainmaking　　

The idea of rainmaking is almost as old as man, but it was not until 1946 that man succeeded in making rain. In ancient times, rainmakers had claimed to bring rain by many methods: dancing, singing, killing various kinds of living creatures (including humans) , and blowing a stream of water into the air from a kind of pipe.　

　More recently, some rainmakers claimed to make rain by shooting guns, causing explosions, or burning chemicals, the smoke of which was supposed to cause rain to fall. These rainmakers asked for as much as 1,000 dollars to make an inch of rain. One was so effective that he was almost hanged. He was believed to have caused a twenty-inch rain in southern California that flooded the land, killed several people, and did millions of dollars" worth of damage.　

　Before 1946, rainmakers were either liars or honest people who happened to have good luck. Scientific rainmaking was started in that year by Vincent J. Schaefer, a scientist at the laboratories of the General Electric Company in New York State. His success was the result of a lucky accident that changed years of failure into victory.　　

For a long time, men have understood where rain comes from. Water from the surface of oceans and lakes becomes part of the air, where it forms clouds from which rain falls. But exactly what starts the formation of raindrops was not known until quite recently. A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter. The centers of the drops are so small that the human eye cannot see them. Without such centers, it seems, raindrops do not form.　　

During World War II, Dr. Irving Langmuir, a scientist, was hired by the General Electric Company to study how and why ice forms on the wings of airplanes. He and a young assistant named Schaefer went to a mountain in the state of New Hampshire, where snowstorms are common and cold winds blow.　　

While in New Hampshire, Langmuir and Schaefer were surprised to learn that often the temperature of the clouds surrounding them was far below the freezing point, and yet ice did not form in the clouds. After the War, Schaefer experimented with a machine that created cold, moist air similar to the air found in clouds. To imitate the moist air of a cloud, Schaefer would breathe into the machine. Then he would drop into the freezer a bit of powder, sugar, or some other substance. For weeks and months he tried everything he could imagine. Nothing happened. No crystals of ice were formed. None of the substances would serve as the center of a snow crystal or raindrop.　　

One July morning, Schaefer was dropping in bits of various substances and watching the unsuccessful results. Finally, a friend suggested that they go to eat lunch, and Schaefer gladly went with him. As usual, he left the cover of the freezer up, since cold air sinks and would not escape from the box.　　

Returning from lunch, Schaefer was beginning to perform his experiments again when he happened to look at the temperature of the freezer. It had risen to a point higher than that required for ice crystals to remain solid. The warm summer weather had arrived without his noticing it. He would have to be more careful in the future.　　

There were two choices now. He could close the cover and wait for the freezer itself to lower the air temperature, or he could make the process occur faster by adding dry ice, a gas in solid form that is very, very cold. He chose the latter plan. He decided to try a container of dry ice.　　

As he dropped the steaming white dry ice into the freezer, he happened to breathe out a large amount of air. And there, before his eyes, it happened! He had made ice crystals, not by adding centers to the moisture but by cooling the breath so much that the liquid had to form crystals ! Schaefer called to his helpers to come and watch. Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.　　

If he could make snow in a freezer, Schaefer thought, why couldn"t he do so in a real cloud? He decided to try it in an airplane with a machine to blow dry ice out into the clouds.　　

On a cold day in November, Schaefer and Langmuir saw clouds in the sky, and Schaefer climbed into the airplane. He realized he would have to fly some distance before finding the right kind of cloud—a big gray one that must be filled with moisture. Seeing one, Schaefer told the pilot of the plane to fly above the cloud. At the proper time, he started the machine, and dry ice began to fall from the airplane into the cloud below. When half the load of dry ice was gone, the motor stopped because it had become too cold. Schaefer had to think quickly. He merely threw the remaining dry ice out of the window of the plane and into the cloud below.　　

On the ground, Dr. Langmuir watched excitedly and saw snow falling from the bottom of the cloud. When Schaefer returned to the ground, blue with cold, Langmuir ran to him, shouting, "You have made history! " And indeed he had. Almost as soon as the news of his accomplishment was sent across the United States and around the world, a hundred other rainmakers were throwing dry ice into clouds—or "seeding the clouds" as it was called.　　

When Schaefer discovered that ice crystals could be formed without finding the right material to make centers for the crystals, he stopped searching for such materials. But another young worker at General Electric, Bernard Vonnegut began looking through a chemistry book for some chemical compound that might have the right size and shape to form crystals around it. He found what he was booking for. It was a compound called silver iodide(碘化银). He got some silver iodide and developed a way of burning it to produce tiny particles that would separate in the air and form snow—he hoped.　　

Finally he shot the material up into the air and waited for the storm. Nothing happened. He couldn"t understand why. The compound ought to form enters for crystals. He asked a scientist to examine the chemicals he had used. There was the trouble. The silver iodide he had used was not pure.　　

He got more of the material, performed his experiment again, and there were the snow crystals! Today, scientific rainmakers generally use silver iodide, Which can be sent into the air from the ground by means of a simple, inexpensive machine. This process is more satisfactory than the use of dry ice which can be destructive.　　

1. Human beings were able to make rain in ancient times.　　

2. Dr. Irving Langmuir and Schaefer went to New Hampshire to study how and why ice forms on the wings of airplanes.　　

3. Schaefer found out the rain drops could be made without having to search the right material to make their centers.　　

4. Using silver iodide to make rain is more satisfactory than using dry ice.　　

5. Rain can be made by shooting salt onto the clouds.　　

6. Schaefer found the warm summer weather was favorable for rainmaking.　　

7. Bernard Vonnegut looked through a chemistry book to find whether silver iodide was the right material for making rain. 8. Schaefer succeeded in making ice crystals by cooling the breath so much that the liquid　　______crystals.　　

9. In New Hampshire Schaefer experimented with a machine creating cold, moist air　　similar to the air or other matter.　　

10. According to John Aitken, water drops gather around__　　

答案：1. N 2. Y 3. Y 4. Y 5. NG 6. N 7. N 8. had to form 9. found in the clouds 10. tiny bits of dust

篇二:[杭州人工降雨2017]人教版小学五年级语文下册单元试卷

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一、看拼音，写汉字。(16分)　　tǎn yín yū tí mào　　绿( 毯 ) 低( 吟 ) ( 迂 )回 马( 啼 ) 礼( 貌 )　　jū jiāo xuàn yá jùn　　( 拘 )束 摔( 交 ) ( 渲 )染 天( 崖 ) ( 骏 )马　　lè xiu sè xī shào jiāng　　勾( 勒 ) (羞 涩) 清( 晰 ) 介( 绍 ) 新(疆 )　　二、将词语补充完整。(4分)　　一( 碧 )千里 翠色( 欲 )流 (襟 )飘带舞 ( 浑)黄一体　　三、词语搭配。(10分)　　茫茫的 白杨树 高大挺秀的 冻土　　小小的 昆仑山 银装素裹的 灯火　　粗壮的 大戈壁 斗志高昂的 身影　　高大的 争论 彻夜通明的 风火山　　巍峨的 枝干 逞凶一时的 筑路大军　　四、按课文内容填空(20分)　　1、那里的天比别处的天更可爱，空气是那么( )，天空是那么( )，使我总想( )，表示我满心的( )。　　2、羊群一会儿上了小丘，一会儿又下来，走在哪里都像( )。　　3、白杨树从来就这么直。( )需要它，它就在( )很快地生根发芽，长出粗壮的枝干。( )遇到风沙还是雨雪，( )遇到干旱还是洪水，它( )那么直，那么( )，不( )，也不( )。　　4、( )，浪淘风簸自之天涯。如今直上银河去，( )。　　5、美景——¬¬( )——( )¬——( )——联欢。　　五、给带点的字选择正确的解释。(6分)　　深：① 颜色浓 ② 开始以来经历的时间久 ③ 距离大，跟浅相反　　④ 程度高 ⑤ 极;很 ⑥深入;深远　　1、夜深了，人们都进入了梦乡。 ( )　　2、这件衣服颜色太深了。 ( )　　3、那件事产生了很深远的影响。 ( )　　4、那口井特别深。 ( )　　5、蒙汉情深何忍别，天涯碧草话斜阳! ( )　　6、我们对他的遭遇深表同情。 ( )　　六、选词填空。(6分)　　可是 由于 尤其　　1、上网冲浪可以开阔我们的视野，丰富我们的知识，( )也要注意节制。　　2、( )连续高温，杭州采取了人工降雨的办法以减缓旱情。　　3、暑假里，小学生要特别注意人身安全，( )是在游泳时，一定要有大人带领。　　七、照样子，改写句子。(6分)　　例：这是一个娇嫩的小生命。　　这是一个多么娇嫩的小生命呀!　　1、 杭州的西湖是一颗璀璨的明珠。　　2、 人们希望车子能停下来，希望时间能停下来。　　3、 我向往大熊猫的故乡。　　八、请你当医生，给下面的句子治病。(9分)　　1、我敢肯定今天可能会下雨。　　2、教室里的同学都走了，只剩下林飞在订正考卷。　　3、 元宵节，大街上挂满了五颜六色的大红灯笼。　　九、给下面的句子排队，把序号填在括号里。(5分)　　( ) 训练有素的宇航员并不紧张，他们知道，这是飞船脱离了地球引力而产生的失重现象。　　( ) 一艘载着三名宇航员的飞船在火箭的推送下升上了天空，开始了奔赴月球的旅行。　　( ) 他们在座舱里飘来飘去，仔细地检查一个个仪器，还不时地和地面指挥中心联络着……　　( ) 飞船绕地球飞行几圈后，径直向月球加速飞行。　　( ) 这时，宇航员们感到自己的身体轻飘飘的，无法在座舱里站稳，稍一抬脚，就会跳起三四米高。　　十、阅读短文，完成练习。(18分)　　哦!冬夜的灯光(节选)　　我记得一个冬日之夜，有个农民打电话来说只有他一个人在家，而婴儿正在发高烧。虽然汽车里有暖气，他也不敢冒险带婴儿上路。他听说我不管多么晚也肯出诊，因此请我上门去给他的婴儿治病。　　虽然他把到他家的路线说了几遍，我还是弄不清楚。　　“我知道该怎么办了。医生，我会打电话给沿途农家，叫他们开亮电灯，你看着灯光开车到我这里来，我会把开着车头灯的卡车放在大门口，那样你就找得到了。”他在电话里告诉我这个办法，我觉得不错。　　我开着车上路，车窗外面寒风呼呼地怒吼着。果然，正如那位农民所说的，沿途农家全部把灯开亮了。平时，一入夜荒野总是漆黑一片，因为那时候的农家夜里是很节约的。一路的光指引着我，使我终于找到了那个求医的人家。我急忙给婴儿检查病情。这婴儿烧得很厉害，不过没有生命危险。我给婴儿打了针，再配了一些药，然后向那农人交代怎样护理，怎样给孩子服药。当我收拾药箱的时候，我心里在想，那么

篇三:[杭州人工降雨2017]2017山西特岗教师招聘初中化学面试答辩题

教师招聘网权威发布2017山西特岗教师招聘初中化学面试答辩题，更多2017山西特岗教师招聘初中化学面试答辩题相关信息请访问教师招聘网。
题目：在初中化学教学中如何创设教学情境?试举一例。　　【参考答案】　　在化学教学中，关于如何创设教学情境，我主要从以下几方面入手：　　1.联系生活实际，创设教学情境。　　理论联系实际，是每位教育工作者应遵循的原则，更是化学教学必须遵循的原则。理论联系实际，能使学生学以致用，对培养学生的能力，扩大学生的知识面，激发学生的学习动机与兴趣等具有独到的作用。　　2.精心设计问题，创设教学情境。　　在化学课堂教学中，灵活设计问题情境，能获取各种反馈信息，调控教学过程，联系师生感情，启发学生思维，激发学生学习兴趣。　　3.应用化学实验，创设教学情境。　　化学教学区别于其他学科的主要标志是以实验为基础。初中化学作为启蒙化学，实验教学尤为重要，它可以帮助学生形成化学概念，理解和巩固化学知识，培养学生观察现象、分析问题、解决问题的能力以巩固化学知识，并形成学生实事求是、严肃认真的科学态度，丰富学生的感性认识。因此作为化学教师要抓住以实验为基础这一基本特点，做好各种实验，以生动、形象、鲜明的实验现象对学生的认知情感、认知意志产生影响，引起学生的兴趣，使学生由被动接受变为主动探索，以揭开科学知识的奥秘。　　4.灵活穿插故事，创设教学情境。　　中学生特别是初中生，好奇心强，上课的注意力不持久。在课堂教学中，如果能根据教学内容适时地道出一两则故事来，占时不多，效果可不差。　　5.恰当应用多媒体，创设教学情境。　　多媒体在教学中的运用，为课堂教学注入了新的生机，可帮助攻克许多教学中的难关。特别是计算机多媒体，能把那抽象的概念、难以观察到的现象、不易实现的实验，通过信息处理和图像输出，诉之学生的感觉器官，在短时间内能调动学生积极参与活动，从而形成鲜明的感性认识。　　例如：在讲解“二氧化碳的性质”一课时，可以通过对二氧化碳在自然界的循环的讲述，说明二氧化碳在自然界的重要性，引入新课。当学完二氧化碳的性质后，可以让学生用学过的知识解释人工降雨的奥秘以及大自然那千姿百态的钟乳石、石柱、石笋等形成的化学原理。这样，不仅加深了学生对二氧化碳性质的认识，而且大大地提高了学习化学的兴趣。

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