新编英美概况许鲁之(第四版)unit17课后习题简答题答案教学内容

新编英美概况许鲁之(第四版)unit17课后习题简答题答案教学内容
新编英美概况许鲁之(第四版)unit17课后习题简答题答案教学内容

Unit 1 Geographical Features and Natural Resources

1. How many states are there in the United States? And which two states are geographically separated from the others? (50, Alaska, Hawaii)

2. What are the general characters of the Rocky Mountains and the Appalachian Mountains.

1) To the west of Atlantic coastal plain lie the Appalachian Mountains that begin in Canada and reach all the way to Georgia and Alabama. These are old mountains with rounded tops and wooded hills, usually not exceeding 800m in height. The highest point is only 2000m above the sea. Most of the mountain ridges are low enough to be easily crossed by modern highways. The Appalachians have much beautiful scenery and many tourist resorts. The Ohio and the Tennessee Rivers flow down the western slopes of the Appalachians to the great Mississippi River, deep in the heart of America.

2) To the west of the Great Plains lie the Rocky Mountains, “the backbone of the continent”. These high mountains stretch all the way from Mexico to the Arctic and form what is known as Continental Divide, or Great Divide, the most important watershed on the continent. The Rockies are more than twice as high as the Appalachians and high enough to receive more rain than the surrounding plains and plateaus. Consequently, they are mostly forested. The striking and varied scenery of the Rockies has given rise to the establishment of many national parks here. The other natural wonders include roaming herds of buffalo, elk, deer, antelope and sheep, as well as the famous grizzly bear.

Chapter 2 American Population

1.Why is the United States known as a “melting pot”?

It means that the US is composed of immigrants from different nations all over the world.

①The people of the US are predominantly white.

②The second most numerous minority in the US were the black people whose forefathers came from

Africa.

③American Indians were the original inhabitants on the continent.

④There were about 50.5 million Hispanics in 2010 in the US. They are the Spanish-speaking immigrants

from Latin American countries.

⑤The Chinese American have proved to be industrious and intelligent.

2.What factors cause the Americans to move frequently within the United States?

①The desire for economic betterment is generally the most important force inducing migration.

②Geographic difference in economic opportunity, as reflected by such factors as differences in

employment opportunities and earning power for workers and differences in the availability and the price of land for farmers.

③Noneconomic factors. Such as climate, racial attitudes, and family tires, influencing migration.

3.Why do many Americans now migrate from cities to suburbs?

①The widespread uses of automobiles and the construction of express highways made it possible for

people to live farther away from their jobs.

②The telephone reduced the need for them to work or live in close proximity to one another.

③Suburban areas offered more living space than cities, lower crime rates, less pollution, and superior

schools. It is generally believed that they are better place for raising children.

Chapter 3 Discovery and Colonization of the New World

1. Discuss the pre-Columbian cultures in the Americas.

1) The Aztecs of Mexico

2) The Incas of Peru

3) The Indians of North America

4) Indian contributions to European culture: Foods, Drugs and Utilitarian objects

2. Why did the discoveries of New World before Columbus not exert great influence in the world at that time?

Because Europe was then poor and politically fragmented, It was beset by local wars and civil disorder and largely illiterate. In short, Europe was then incapable of responding to the Norse discoveries.

3.Why did so many English people move to the New World in the 17th century?

1) The New World was a great and rich land. In the New World there were all those resources necessary for agricultural and industrial development.

2)During the reign of Queen Elizabeth I (1588-1603), the English in growing numbers realized that the New World was their best place to make their fortunes, and to worship and live according to their beliefs.

3)Some of them might move to America to leave oppressive political institutions, to escape burdensome church duties, to acquire large landholdings or merely to change their general pattern of living. Of course, material gain was a common factor.

4. What was the social structure of the 13 colonies?

Society in the l3 colonies was like a pyramid.

①The top was made up of merchants and landlords.

②The base was made up of refugees from Europe, black slaves from Africa. And native Indians.

5.Why did not the American Indians become slaves during the colonial days?

As for Indians, they could not put up with slavery. If an Indian was enslaved, his fellow tribe members would fight to free him. So the colonialists soon gave up the attempt to use them as slave labor. Instead they seized the land of the Indians and drove them away or killed them.

Chapter 4 American Revolution

2. What happened on the evening of March 5, 1770?

A clash between American colonies and British soldiers took place in Boston.

①A group of unemployed laborer attacked a British sentry stationed at the Boston customhouse.

②When the British soldiers dispatched to help the sentry arrived, they met a rapidly growing, angry crowd.

③Someone gave the command for the soldiers to fire.

④Three colonies were killed and several were wounded, two of whom later died.

3. How did the colonies react to the Townshend Act?

The colonies, however, still rejected the idea that the Parliament in Britain had the right to tax them without consent and reacted to these new duties by refusing to import any of the taxed goods.

4. What were the main contents of the Declaration of Independence?

①The Preamble, which explains why the Declaration was issued.

②A statement of principles of government to which the American people were committed

③A list of injustices suffered by the colonists.

④A summary of efforts the colonies had made to avoid a break with the mother country.

⑤The proclamation is that the “Colonies are Free and Independent States”

5. What was the importance of the victory at Saratoga?

The victory and Saratoga wa s a turning point of the war. It further heightened the spirit of the Americans, but more importantly it caused action abroad. It was after this battle that the French agreed to join the war against Britain. Later Spain and Holland joined France while most of the other European powers

formed an Armed Neutrality to protect their commerce from Britain’s naval power.

Chapter 5 the Confederation and the Constitution

1. What is confederation?

A confederation is a government in which the constituent governments, called states in the US, create a central government by constitutional compact but do not give it power to regulate the conduct of individuals.

2. Compare the powers of the governments under the Articles of Confederation and the Constitution.

3. What does the “check and balance” mean?

It means that each branch of government-executive, legislative, or judicial-must exercise distinct powers and be selected in a distinct way, and that each branch must be able to “check and balance” the others if one branch grew too powerful and sought to dominate the others.

4. What was the Bill of Rights?

It guaranteed freedom of speech, religion, peaceful assembly, and the press; the right to bear arms; freedom from unreasonable search; and the right to the protection of certain legal procedures known as the due process of law.

5. What were the chief causes of the War of 1812?

①The British were not reconciled to the loss of their thirteen colonies. Using Canada as the base, they always challenged to battle with the young Republic.

②This anger reaches its peak in 1807 when one British warship attached and boarded in American ship, killing and wounding 21men and impressing four sailors.

③Jefferson persuaded Congress to pass an Embargo Act, which forbade all ships, except foreign ones without charge, to leave American ports.

Chapter 6 American Expansion and the Civil War

1. What was the importance of the Monroe Doctrine?

The essence was” America for Americans”, which later became a cornerstone of the US foreign policy. As the New world developed in the years ahead this Doctrine became more meaningful and was strengthened by a broader interpretation to meet the needs of an energetic and ambitious United States.

2. What were the basic causes of the Civil War?

Two different social-economic systems existed side by side in the United States.

In the South slavery was the foundation of the economic system while in the North industry and commerce were the main character of its economy. The swiftly growing industries in the North required the restriction of slavery as well as an expanding territory in order to provide capitalist production with raw materials, markets and abundant labor supply.

The slave economy in the South was an obstacle to industrial growth and expansion. This economic antagonism led to increased conflicts between the North and the South.

3. What was the doctrine of the “popular sovereignty”?

This doctrine means that the inhabitants of the new territories can decide the question of slavery for themselves. In appearance, it seemed fair, but in actual practice, as far as slavery was concerned, the doctrine did not work.

4. How do you comment on the American Civil War?

The outcome of the war placed the northern capitalists in solid control of the federal government of the US capitalism. In 1865, the Thirteenth Amendment to the US Constitution was adopted, which freed all slaves throughout the United States.

Chapter 7 Reconstruction and the Birth of US Imperialism

1. What is the 10 percent plan?

The plan provided that as soon as 10 percent of voters in any state had taken the oath of loyalty, they could form their own government and would be entitled to the recognition of their state by the president of the United States.

2. Why was Andrew Johnson impeached by the House?

In March 1867, Congress passed two Acts that took away two presidential prerogatives: the right to remove Cabinet members and the right to remove army officers under his command.

To test the constitutionality of the Act, President Andrew Johnson removes Edwin M. Stanton, the Secretary of War, from office in1869, who was the only remaining Radical in Johnson’s Cabinet.

He thus walked into troubles with the radicals. Later the House voted to impeach the President.

3. After the Reconstruction, how were the civil rights of the Blacks in the South?

①Voters must be able to read and write;

②Voting taxes were introduced;

③The whites also took steps to segregate the blacks and two separate societies emerged in the South.

4. Why did the US have a rapid industrial growth after the Civil War?

①The vast industrial development began with the opening the West.

②Speeding this process of western settlement were the railroads.

③Science and technology were also greatly marching forward.

④The basic industry of the nation, iron and steel, also developed rapidly after the Civil War.

⑤The oil industry also developed rapidly.

⑥During the latter part of the 19th industry, industrial expansion in America went ahead rapidly.

⑦There was a clear indication of rapid concentration of capital.

6. What was the “Open Door Policy”?

The so-called “Open Door Policy”which demanded that all the imperialist powers should enjoy equal chance in China as freely as other aggressors.

电焊工考试题及答案全

氩弧焊时产生的有害气体是,(臭氧和氮氧化物)。 (HF)气体会严重危害焊工健康。 弧焊变压器过热的主要原因是变压器过载,(绕组短路)。 接地导线应具有良好的导电性,其截面积不得小于(12)mm2 对焊工没有毒害的气体是(二氧化碳)。 焊工吸入大量金属烟尘,引起急性升高的现象称,(焊工金属热)。 在场内或人多的场所焊接应放置(遮光挡板),以免他人受弧光伤害。 手工电弧焊时要求焊接回路的电压降应不大于(4v)。 现场急救常用的人工呼吸法是(口对口)人工呼吸法。 高频振荡器会产生一定的(电磁辐射),对焊工的身体有不利影响。 焊接作业现场与易燃易爆物品的安全距离一般不小于(10)米。 焊接的辐射危害主要由可见的强光,不可见的紫外线,(红外线)等。 焊接时由焊接材料,母材及其冶金反应产生等的蒸发,氧化产生在空气中浮游的颗粒,称为(焊接烟尘)。 装配焊接时应(配合协调)。当焊工引燃电弧时,配合工要做好保护工作,避免受和光的照射。 采用交流电源焊接时,电弧的积极性周期性变化,即每秒钟电弧的(燃烧和熄灭)要重复100次。 一切灭火措施,都是为破坏产生(燃烧)的条件。 (紫外线)过度照射会使眼睛造成电光性眼炎。 常见焊接接头形式中,受力最好的是(对接接头)。 一判断题。 灭火时应同时采用防中毒,倒塌坠落伤人等措施。(√) 焊接作业中的放射性防护主要是防止含钨的气体进入体内。(×) 焊工如果长期受强紫外线照射会引起“水晶体内降”眼病,严重的可使人失明。(×) 焊条电弧焊的引弧方法是短路引弧。(√) 触电急救进行胸外心脏挤压,其频率一般应为每分钟60-80次。(√) 有害物质指有害于健康的气态和颗粒状的物质包括气体,烟雾灰尘的统称。(√) 作业场所附近与明火相抵触的工种,只要小心些,可以焊割。(×) 乙炔是有爆炸性的危险气体。(√) 单相触电时加在人身上的电压为220伏,双相触电时加在人身上的电压为380伏。(√) 电伤对人体的伤害其主要是电弧烧伤和熔化金属溅出烫伤。(√) 噪声对人体的危害程度与频率和人的听力有关。(×) 在线路设置有防触电安全装置条件下,安全电流可按30mA考虑。(√)有毒气体氟化氢主要产生于co2气体保护焊。(×) 氟化物对人体的主要危害表现呼吸道危害。(×) 置换焊补时,安全隔离的最好办法是在厂区或车间内划定一个安全作业区。(√) 触电的现场急救是整个触电就工作的关键。(√) 靠近高压电网和电器设备所发生的触电事故,称为(直接电击)。 焊机的保护接地和保护接零系统不牢,会导致(间接触电)事故。 焊接黑色金属时,金属烟尘中主要毒物是(锰)。 在较短时间内,能引起心室颤动的最小电流,称为(致命电流)。

新编英美概况许鲁之(第四版)Unit1-12课后习地的题目选择填空

实用标准文档 精彩文案Chapter1 Geographical Features and Natural Resources 1.In area, the United States is the 4th largest country in the world. 2.The Midwest in the US refers to the region around the Great Lakes and the upper Mississippi Valley. 3.The Backbone of North America refers to the Rocky Mountains 4.Death Valley is on the western edge of the Great Basin. 5.The Great Plains might have a dust storm in summer. 6.The western part of Washington State h as the highest rainfall in the US. 7.The US primary suppliers of foreign oil are the following countries except Japan 8.The US largest open-pit copper-mining center is in Utah. 1. The United States is bordered on the north by Canada, on the south by Mexico and the Guff of Mexico, on the east by the Atlantic Ocean, and on the west by the Pacific Ocean. 2. The large territory of the continental US is divided into three basic areas: A. the Atlantic seacoast west to the Appalachians B. the Mississippi River Basin C. the Rockies west to the Pacific 3. The Middle Atlantic States are the most densely populated region in the US, where the land is flat and fertile. 4. The Central Valley of California is a highly productive area, which produced enormous amounts of fruits and vegetables. 5. Most production of oil and natural gas in the US comes from offshore areas of Louisiana and Texas, a nd from onshore areas of Texas, Oklahoma a nd California. Her big consumption of energy now has made America insufficient in oil supply. The US reliance of foreign oil has reminded consistently in the 40% ranges. 6. The United States has little trouble caused by the shortage of fresh water. Farmlands in the US making up about 12% of the arable lands in the world, and they are among the richest and most productive. Chapter 2 American Population 1.The over 3 million of early Americans in 1790 were mostly of British ancestry. 2.About 700,000 immigrants were legally received by the US each year during the 1980s. 3.The official racial segregation continued to be the law of the US until 195 4. 4.American Indians now mainly live in the South. 5.The majority of American Hispanics are from the following countries except Spain. 6.The West now leads in percentage increase in population. 7.According to the 1994 US census, the second most populous state in the US is Taxes. 8.The trend in migration from cities to suburbs now prevailed in all regions except the South. 1.The United States is the third most populous nation in the world. 2.Prior to 1875 anyone from any country could enter the US freely and take up permanent residence there. Later the US Congress passed laws restricting immigration on the basis of morality, race, and national origin. The 1952 Immigration and Nationality Act reaffirmed national origin as the chief criterion for eligibility and established a preferential system for skilled workers and for relatives of the US citizens. For many years the US restricted to total number of immigrants to 270,000 each year, although the real immigrants numbered much greater than the limit. The 1990 Immigration Act limits the total number of immigrants to 700,000 from 1992 to 1995 and 675,000 thereafter. 3.The first blacks arrived in Jamestown in 1619 as indentured servants,but soon[ after 1619 they were brought to colonies as slaves.The blacks were formally freed in1863, but continued to suffer the institutionalized segregation for about a century. Today many blacks still live in the South, some have entered the middle class, but one-third of all black families still live below the poverty line. 4.The Chinese-Americans have proved to be industrious and intelligent. They are now viewed as a “ model minority” in the US. According to the 2010 US census, there were about 3.8 million Chinese-Americans living in the US. The figure was more than twice what it was in 1990. Chapter 3 Discovery and Colonization of the New World 1. The ancestors of the present American Indians came from Asia. 2.“The ambition for the vast lands”is not correct to explain the reasons for the sudden daring exploration of the unknown in the mid-15th century.

电焊工理论考试题及答案

电焊工理论考试题及答案 Final revision by standardization team on December 10, 2020.

电焊工理论考试题及答案 一、填空题(共计30道、总计105道) 1、手工电弧焊时向焊缝渗合金的方式主要是通过(焊芯)和(药皮)过渡。 2、焊接低合金结构钢时,在焊接接头纹有(冷裂纹)、(热裂纹)、再热裂纹,其中尤以(冷裂纹)最为常见。 3、焊缝按断续情况不同可以分为(定位焊缝)、(连续焊缝)和(断续焊缝)。 4、当焊条直径相同时,由于不惜滚撒个焊条的电阻率比低碳钢(大),产生的电阻热(大),所以长度比碳钢焊条(短)。 5、焊接过程中,焊接区内充满大量气体,主要来自(焊接材料)、(空气)焊丝和母材表面上的杂质和高温蒸发产生的气体。 6、焊接按结合形式不同可以分为(对接焊缝)、(角焊缝)和(塞焊缝)。 7、溶滴过渡是的飞溅会影响电弧燃烧的(稳定性),焊接不锈钢时还会降低母材金属的(抗腐蚀性)。 8、熔化极电弧焊时,焊条(或焊丝)具有两个作用:一方面作为(电弧的一个极);另一方面(向溶池提供填充金属)。 9、熔化极电弧焊时,熔化焊条(或焊丝)的热量有(电阻热)、(电弧热)和(化学热) 10、焊条长度不能制造过长的原因是焊条长度增加时,焊条末端的通电时间(增加),电阻热(加大),药皮容易发红而变质。 11、减少焊接残余应力的措施不正确的是先焊(收缩较小焊缝)

12、奥氏体不锈钢中主要的合金元素是(铬)和(镍),他们在所起的作用分别是保证钢的耐腐性和改善钢的(组织和性能)、有较好的工艺性能和力学性能。 13、根据焊接过程中金属索处地不同状态,焊接方法可分为(熔焊)(压焊)和(钎焊)三类。 14、手工电焊电弧的引燃方法有(直击法)和(划擦法)两种。 15、短弧是指电弧长度小于(焊条直径)的电弧。 16、焊接时对塑性、韧性和抗裂性要求较高的焊缝,应选用(碱性)焊条。 17、同一种焊芯的焊条、其直径越大,则焊条越(长),这是因为直径越大,电阻越(小),相应电阻热也越小,故可以(增加)焊条长度。 18、焊接电流主要影响焊缝的(溶深)。 19、电弧电压主要影响焊缝的(溶宽)。 20、焊工用护目玻璃的号越大,则色泽越(深)。 21、预防和减少焊接缺陷的可能性的检验时(焊前检验)。 22、硫和磷都是有害杂质,它能使焊缝金属的(力学性嫩)降低。 23、手工电弧焊时,电弧产生的热量仅有一部分用来熔化(焊条),大部分热量用来熔化(母材)、(药皮),另外还有相当部分的热量消耗在(辐射)、飞溅和母材传热上。 24、不锈钢中最危险的一种破坏形式是(晶间腐蚀) 25、(焊接工艺参数)是指焊接时为保证焊接质量,而选定的诸物理量地总称。 26、为了减少焊接变形,应选择(X 型坡口).

电焊工题库及答案

电焊工题库及答案

一、单项选择题(每题1分,共15分) 1. 氧气瓶应涂( ),用( )颜色标明“氧气”字样;乙炔气瓶应涂( ),并用( )标明“乙炔”字样。(C) A天蓝色,黑,白色,红色 B天蓝色,红,白色,黑色 C天蓝色,黑,白色,黑色 D天蓝色,红,白色,红色 2. 所有升降口、大小孔洞、楼梯和平台,应装设不低于( )mm 高的栏杆合不低于( )mm高的护板。(C) A1200,100 B1500,100 C1050,100 D1200,50 3. 手持行灯电压不准超过( )V。在特别潮湿或周围均属金属导体的地方工作时,如在汽包、凝汽器、加热器、蒸发器、除氧器以及其他金属容器或水箱等内部,行灯的电压不准超过( )V。(D) A12,24 B24,24 C36,24 D36,12 4. 所有高温的管道、容器等设备上都应有保温,保温层应保证完整。当室内温度在( )℃时,保温层表面的温度一般不宜超过( )℃。(A) A 25,50 B35,50 C35,60 D25,60 5. 凡在坠落高于基准面( )m及以上的高处进行的作业,都应视作高处作业,在没有脚手架或者在没有栏杆的脚手架上工作,高度超过( )m时,应使用安全带。(A) A2,1.5 B2,2 C1.5,1.5 D1.5,2 6. 作业人员应按其职务和工作性质,学习本规程的全部或部分,并应每年考试( )次,考试合格方能上岗。因故间断工作连续( )个月以上者,应重新学习本规程,并经考试合格后,方能恢复工作。 (B) A一,三 B一,六 C二,三 D二,六 7.若确需变更工作负责人时,应由原工作票签发人同意并通知( ),( )将变动情况记录在工作票上。非连续工作的工作负责人允许变更( )次。(D) A工作负责人,工作负责人,一 B工作负责人,工作许可人,二

新编英美概况-许鲁之(第四版)Unit1-12课后习题选择填空.doc

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Chapter 1 Geographical Features and Natural Resources 1. Choose the correct answer 1-8 CDBACBBB 2. fill in the blanks 1. Ca nada\Mexico\the Cuff of Mexico\Atla ntic Ocea n\the Pacific Ocea n 2. The Atla ntic seacoast west to the Appalacha in s\The Mississippi River Basin\The Rockies west to the Pacific 3. most den sely\flat\fertile 4. productive\fruits\vegetables 5. Louisia na\Texas\Texas\Oklahoma\Califor ni a\i nsufficie nt\4O% 6.little\fresh\12%\richest\productive Chapter 2 America n Populati on 1. Choose the correct answer 1-8 CBDACDCB 2. fill in the blanks 1. third\250 2.1875\perma nent reside nce\morality\race\nati onal origi n\n ati onal origi n\skilled\relatives\270,000\700,000\675,000 3.i nden tured serva nts\slaves\1863 4.South\poverty line 5.i ndustrious'i ntellige nt'modle min ority'twice

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