7.简述硅片制备的基本过程-找考题网

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The word 'omnipresent' in ParA.3 probably means ______.A.eternalB.strategicC.present everywhereD.sovereign

问答题

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The full influence of mechanization began shortly after 1850, when a variety of machines came rapidly into usE.The introduction of these machines frequently created rebellions by workers who were fearful that the machines would rob them of their work. Patrick Bell, in Scoffland, and Cyrus McCormick, in United States, produced threshing machines. Ingenious improvements were made in plows to compensate for different soil types. Stream power came into use in 1860s on large farms. Hay rakes, hay-loaders, and various special harvesting machines were produceD.Milking machines appeareD.The internal-combustion engine run by gasoline became the chief power source for the farm.In time, the number of certain farm machines that came into use skyrocketed and changed the nature of fanning. Between 1940 and 1960, for example, 12 million horses and mules gave way to 5 million tractors. Tractors offer many features that are attractive to farmers. There are, for example, numerous attachments: cultivators that can penetrate the soil to varying depths, rotary hoes that chop needs; spray devices that can spray pesticides in bands 100 feet across, and many others.A piece of equipment has now been invented or adapted for virtually every laborious hand or animal operation on the farm. In the United States, for example, cotton, tobacco, hay, and grain are planted, treated for pests and diseases, fertilized, cultivated and harvested by machinE.Large devices shake fruit and nut from trees; grain and blend feed, and dry grain and hay. Equipment is now available to put just the right amount of fertilizer in just the right place, to spray and exact row width, and to count out, space, and plant just the right number of seeds for a row.Mechanization is not used in agriculture in many parts of Latin America, AfricA.Agriculture innovation is accepted fastest where agriculture is already profitable and progressivE.Some mechanization has reached the level of plantation agriculture in parts of the tropics, but even today much of that land us laboriously worked by people leading draft animals pulling primitive plows.The problems of mechanization in some areas are not only cultural in naturE.For examples, tropical soils and crops differ markedly from those in temperate areas that the machines are designed for, so adaptations have to be madE.But the greatest obstacle to mechanization is the fear in underdeveloped countries that the workers who are displaced by machines would not find work elsewherE.Introducing mechanization into such areas requires careful planning.The first paragraph uses several examples to convey the ideas that ______.A.the introduction of machines into agricultural work created rebellions on the part of the farmersB.the use of internal-combustion engine as a chief power source for the farm produced great influenceC.the mechanization of agricultural work after 1850 gradually robbed many farmers of their workD.ingenious improvements were made in fanning machines in the 1860s to yield production

A.B.
C.
D.
E.
The
F.
A.the
G.the
H.the
I.ingenious

单项选择题

在激烈国际竞争中，惟（）者进，惟（）者胜。 A、创新科技 B、创新创新 C、科技科技 D、科技创新

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假如你的某个老同学要你帮他一个“小忙”。虽然这事违反了规定．但显然不会出问题，你会( )。资源的稀缺性的属性包括( )。A.暂时的稀缺性B.绝对的属性C.相对的稀缺性D.永久的属性E.消费劳动资源支付手段的稀缺性

A.但显然不会出问题，你会(
B.暂时的稀缺性
B.绝对的属性
C.相对的稀缺性
D.永久的属性
E.消费劳动资源支付手段的稀缺性

判断题

体校田径运动队教练是当然体育参与者。正确错误

单项选择题

对外贸易依存度是指( )。 A．一国贸易差额占其GDP的比重 B．一国对外贸易总额占其GDP的比重 C．一国出口额占其GDP的比重 D．一国进口额占其GDP的比重

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应用作业条件危险性评价法D.不容许风险

A.可容许风险
B.中度风险
C.重大风险

单项选择题

力学系统中工程制单位制度中的长度基本量纲是哪个？单选 A、F B、M C、L D、T

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系统应用架构设计中，网络架构数据流图的主要作用是将处理器和设备分配到网络______不属于网络架构数据流图的内容。D.传输协议

A.服务器、客户端及其物理位置
B.处理器说明信息
C.单位时间的数据流大小