下列物质在玻璃、洗涤等工业上广泛应用,著名化学家侯德榜先生曾对改进它的生产技术做

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问题:

下列物质在玻璃、洗涤等工业上广泛应用,著名化学家侯德榜先生曾对改进它的生产技术做出过杰出贡献的是

A.NaCl

B.Na2CO3

C.CuSO4

D.KNO3

考点:石灰石的利用盐的用途
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利福霉素是一种抗生素,它强烈抑制革兰阳性菌和结核分枝杆菌等细菌的生长,其作用机理是抑制细菌的()

A.DNA聚合酶

B.RNA聚合酶

C.mRNA翻译起始

D.核糖体移位

E.DNA损伤修复

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Today about 70 countries use Daylight Saving Time (DST). Daylight Saving was first introduced during World War I in Australia. During the world wars, DST was used for the late summers beginning January 1917 and 1942, and the full summers beginning September 1942 and 1943.  

In 1967, Tasmania experienced a drought(干旱). The State Government introduced one hour of daylight saving that summer as a way of saving power and water. Tasmanians liked the idea of daylight saving and the Tasmanian Government has declared daylight saving each summer since 1968. Persuaded by the Tasmanian Government, all states except two passed a law in 1971, for a test use of daylight saving. In 1972, New South Wales, South Australia and Victoria joined Tasmania for regular daylight saving, but Queensland did not do so until 1989.

Tasmania, Queensland and South Australia have had irregular plans, often changing their dates due to politics or festivals(节日). For example, in 1992, Tasmania extended(延长)daylight saving by an extra month while South Australia began extending daylight saving by two weeks for the Adelaide Festival. Special daylight saving plans were made during the Sydney 2000 Olympic Games.

The differences in daylight saving in Australia continue to cause serious problems in transport and many other social activities. It also reduces the number of hours in the working day that are common to all centers in the country. In particular, time differences along the east coast cause major differences, especially for the broadcasters of national radio and television.

小题1:Daylight Saving Time was introduced in Tasmania _______________.

A.to stop the drought in 1967

B.to support government officials

C.to pass a special law in the state

D.to save water and electricity小题2: According to the text, which state was the last to use DST?

A.Victoria.

B.Queensland.

C.South Australia.

D.New South Wales.小题3: What can we learn about DST in some Australian states?

A.It doesn’t have fixed dates.

B.It is not used in festivals.

C.Its plan was changed in 2000.

D.It lasts for two weeks.小题4: What do we know about the use of DST from the last paragraph?

A.There exist some undesirable effects.

B.It helps little to save energy.

C.It brings about longer working days.

D.Radio and TV programs become different.

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既可酒炙又可炒炭的药物是()

A.乌梅

B.山茱萸

C.何首乌

D.黄芩

E.黄连

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在物价持续下跌时期,企业发出存货的计价方法由原来的加权平均法改为先进先出法,会使得企业()。

A.低估当期利润,高估库存存货价值

B.低估当期利润,低估库存存货价值

C.高估当期利润,高估库存存货价值

D.高估当期利润,低估库存存货价值

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法定压力计量单位与工程压力单位的换算关系是:1kgf/cm2=9.80665x104Pa=98066.5Pa。

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