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问题 填空题

评定重选设备工艺效果的指标有（）、（）和（）。

答案

参考答案：可能偏差或不完善度；数量效率；错配物总量

单项选择题

某女士，30岁，因患有系统性红斑狼疮3次住院。此次因发热，颧颊部出现蝶形红斑3天入院，查小便尿蛋白阴性，查血抗双链DNA抗体阳性，抗核抗体阳性。

治疗本病主要用药是( )

A．阿司匹林
B．氯喹
C．肾上腺糖皮质激素
D．雷公藤
E．免疫抑制剂
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单项选择题

ICE


1Two conditions are necessary for the formation of ice: the presence of water and temperatures below freezing. Ice in the atmosphere and on the ground can assume various forms, depending on the conditions under which water is converted to its solid state~ Ice that forms in the atmosphere can fall to the ground as snow, sleet, or hail. Snow is an assemblage of ice crystals in the form of flakes; sleet is a collection of frozen raindrops, which are actually ice pellets. Hail consists of rounded or jagged lumps of ice, often in layers like the intemal structure of an onion. Ice also forms directly on the ground or on bodies of water. In North America, ice forms in late autumn, winter, and early spring. On very large bodies of water, it may not form until late winter because there must be several months of low temperatures to chill such large amounts of water.
2On puddles and small ponds, ice first freezes in a thin layer with definite crystal structure that becomes less apparent as the ice thickens. On lakes large enough to have waves, such as the Great Lakes, the first ice to form is a thin surface layer of slush, sometimes called grease ice, which eventually grows into small floes of pancake ice. If the lake is small enough or the weather cold enough, the floes may freeze together into a fairly solid sheet of pack ice. Pack ice may cover the entire lake or be restricted to areas near the shore.
3Because water expands when it freezes, ice is less dense than liquid water and therefore floats rather than sinks in water. As ice floats on the surface of a lake, ocean, or river, it acts as an insulator and is thus important in maintaining the balance of the ecosystem. Without the insulating effect of floating ice sheets, surface water would lose heat more rapidly, and large bodies of water such as the Arctic Ocean and Hudson Bay might freeze up completely.

Ice that forms in the atmosphere in the form of layered lumps is known as

A．snow

B．pack ice

C．hail

D．grease ice
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