Title：The Development of Printing
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2017年11月11日 | |
Printing with movable type, a revolutionary departure from the old practice of copying by hand, was invented in the 1440s by Johannes Gutenberg, a German goldsmith. Mass production of identical books and pamphlets made the world of letters more accessible to a literate audience. Two preconditions proved essential for the advent of printing: the industrial production of paper and the commercial production of manuscripts.
Increased paper production in the fourteenth and fifteenth centuries was the first stage in the rapid growth of manuscript books—hand-copied works bound as books—which in turn led to the invention of mechanical printing. Papermaking came to Europe from China via Arab intermediaries. By the fourteenth century, paper mills were operating in Italy, producing paper that was much more fragile but much cheaper than parchment or vellum, animal skins that Europeans had previously used for writing. To produce paper, old rags were soaked in a chemical solution, beaten by mallets into a pulp, washed with water, treated, and dried in sheets—a method that still produces good-quality papertoday.
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Title：The Climate of Japan题目
1. According to paragraph 1, all of the following are true of the cold air from Siberia EXCEPT:
It gathers moisture as it moves across the Sea of Japan.
It is responsible for the snow that falls on the western side of Honshu Island.
It is warmed by the cyclonic airflows from the south that mix with it.
It is responsible for the cold, dry weather of the eastern valleys and coastal plains and cities.
Paragraph 1 is marked with an arrow .
Paragraph 2
In spring the Siberian air mass warms and loses density, enabling atmospheric currents over the
Pacific to steer warmer air into northeast Asia. This warm, moisture-laden air covers most of southern
Japan during June and July. The resulting late spring rains then give way to a drier summer that is
sufficiently hot and muggy, d espite the island chain’s northerly latitude, to allow widespread rice
cultivation.
2. The word “enabling” in the passage is closet in meaning to
preparing
requiring
allowing
distributing
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类别：生物类
Title：Poikilotherms
参考阅读：
Physiologically, animals can be divided into three groups: homeotherms, which maintain a fairly constant internal temperature regardless of the external temperature; poikilotherms, which have a body temperature that varies according to the surrounding environmental temperature; and heterotherms, which sometimes maintain a fairly constant body temperature and sometimes do not.
Poikilotherms, such as amphibians and insects, have a high thermal or heat conductance between the body and the environment, and a low metabolic rate. For this reason body temperature and thus tissue temperature changes with environmental temperature. Being ectothermic and manitaining body temperature by using sources of heat energy such as solar radiation rather than metabolism has advantages. Prisoners of environmental temperatures, poikilotherms of temperate regions, such as snakes, become highly active only when temperature is adequately warm. Because their metabolic activity declines with decreasing temperature, these animals become sluggish in the cool of morning and evening. Similarly, they have to restrict their activity to the late spring, summer and early fall. During periods of intense physical activity, when energy consumption is high, poikilotherms depend on the anaerobic (without oxygen) breakdown of glycogen (sugars stored for energy). These breakdown results in an accumulation of lactic acid in the tissues, and the lactic acid can be oxidised only after activity ceases. Anaerobic metabolism severely limits bursts of poikilothermic activity to a few minutes, because of physical exhaustion. This tendancy to become exhausted is one reason that so many predatory terrestrial poikilotherms, such as snakes and alligators, secure prey by ambush rather than by chase.
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