简述胶结物和杂基的概念及其成因意义。

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问题:

简述胶结物和杂基的概念及其成因意义。

考点:岩石矿物材料学岩石矿物材料学题库
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已知直线经过点(2,1),且平行于直线y=3x,则这条直线的解析式为______.

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如图,拉动木块在粗糙程度不变的水平桌面上做加速运动.以下说法中正确的是(  )

A.木块受到的摩擦力逐渐减小

B.木块受到的摩擦力不变

C.木块受到的摩擦力逐渐增大

D.木块受到的摩擦力大小等于它受到的拉力

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桌子上摆着金匣子、银匣子和铜匣子。金匣子上写着一句话:“珠宝不在此匣中”,银匣子上写着一句话:“珠宝在金匣中”,铜匣子上写着一句话:“珠宝不在此匣中”。 现已知道,这三句话中,只有一句话是真的,那么()。

A.珠宝在金匣中

B.珠宝在银匣中

C.珠宝在铜匣中

D.珠宝不在任何匣中

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Part 1


·Read thefollowingpassage, eight sentences have been removed from the article.
·Choose from the sentences A-H the one whichfits each gap.
·For each gap (1-8) mark one letter (A-H) on the Answer Sheet.
·Do not mark any letter twice.
The single, decisive factor that made it possible for mankind to settle in permanent communities was agriculture. (1) Once people could control the production of food and be assured of a reliable annual supple of it, their lives changed completely.
Fanning was a revolutionary discovery. (2) With more food available, more people could be fed. Populations therefore increased. The growing number of people available for more kinds of work led to the development of more complex social structures. (3)
Farming the world over has always relied upon a dependable water supply. For the earliest societies this meant rivers and streams or regular rainfall. (4) Later communities were able to develop by taking advantage of the rainy seasons.
All of the ancient civilizations probably developed in much the same way, in spite of regional and climatic differences. (5) Heavier pottery replaced animal-skin gourds as containers for food and liquids. Cloth could be woven from wool and flax. Permanent structures made of wood, brick, and stone could be erected.
The science of mathematics was an early outgrowth of agriculture. People studied the movements of the moon, the sun, and planets to calculate seasons. (6) With a calendar it was possible to calculate the arrival of each growing season. Measurement of land areas was necessary if property was to be a factor in farming and housekeeping. (7) All of the major ancient civilizations in Mesopotamia, Egypt, the Indus Valley, and China emerged in the 4th millennium BC. Historians still debate over which one emerged first. It may well have been the Middle East, in an area called the Fertile Crescent. This region stretches from the Nile River in Egypt northward along the coast of former Palestine, then eastward into Asia to include Mesopotami
  • a. (8) This kind of larming depended on the reproduction of seed, normally from grain crops.A. It not only made settlements possible and ultimately the building of cities but it also made available a reliable food supply.B. Later came measures of value as commodity and money exchange became common.C. In this area people settled along the riverbanks and practiced field agriculture.D. After farming was developed in the Middle East in about 6500 BC, people living in tribes or family units did not have to be on the move continually searching for food or herding their animals.E. As villages grew, the accumulation of more numerous and substantial goods became possible.F. With a food surplus, a community could support a variety of workers who were not farmers.G. The first great civilizations grow up along rivers.H. In doing so they created the first calendars.

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