室内配电装置的母线应满足的安全距离:带电体至接地部分为(),不同相的带电体之间为()

题型:填空题

问题:

室内配电装置的母线应满足的安全距离:带电体至接地部分为(),不同相的带电体之间为()。

考点:纺丝工考试纺丝工考试题库
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取得销售(预售)许可证满3年仍未销售完毕的,主管税务机关可要求纳税人进行土地增值税的清算。()

题型:填空题

(7分)某同学进行试验探究时,欲配制10%的Ba(OH)2溶液,但只找到在空气中暴露已久的Ba(OH)2试剂。在室温下配制溶液时发现所取试剂在水中仅部分溶解,烧杯中存在未溶物。为探究原因,该同学查得Ba(OH)2在20℃时的溶解度2.1 g。

(1)烧杯中未溶物仅为BaCO3,理由是(用化学方程式表示)                

(2)假设试剂由大量Ba(OH)2和少量BaCO3组成,设计试验方案,进行成分检验,在答题卡上写出实验步骤、预期现象和结论。

限选试剂及仪器:稀盐酸、稀硫酸、NaOH溶液、澄清石灰水、氯化铜溶液、烧杯、试管、带塞导气管、滴管

实验步骤预期现象和结论
步骤1:取适量试剂于洁净烧杯中,加入足量蒸馏水,充分搅拌,静置,过滤,得滤液和沉淀。 
步骤2:取适量滤液于试管中,滴加稀硫酸。  生成,说明有Ba2+
步骤3:取适量步骤1中的沉淀于是试管中,滴加稀盐酸,用带塞导气管塞紧试管,把导气管插入装有澄清石灰水的烧杯中。试管中有 生成,烧杯中      ,结合步骤2说明沉淀是BaCO3
步骤4:取适量滤液于试管中,      试管中有蓝色沉淀生成,说明有大量的OH,综合上面步骤可知试剂由大量Ba(OH)2和少量BaCO3组成,假设成立。
(3)在20℃室温下,    (填“能”或“不能”)配制10%的Ba(OH)2溶液。

五、计算与分析题(共2小题,共10分)

目前已制得的纯金属只有90余种,但由这些纯金属按一定组成和质量比制得的合金已达几千种。由于合金更容易适合不同的用途,因此被大量应用于日常生活、工农业及科学研究中。结合所学知识,完成27、28题。

题型:填空题

Kenya wants to organize a major international conference to discuss how to fight piracy(海盗) off the coast of Somalia. The conference may also deal with ways to rescue Somalia from seventeen years of civil war. More than forty percent of its people depend on food aid.

Kenyan Foreign Minister Moses Wetangula says the world cannot end piracy and civil war without dealing with Somalia’s political problems.

Somali pirates operate in the Indian Ocean and the Gulf of Aden. The Gulf of Aden connects the Red Sea to the Mediterranean by way of the Suez Canal. The pirates have fast boats, modern weapons and equipment like satellite phones and global positioning systems.

Pirates hijacked the Sirius Star off the coast of Kenya and moved it to waters off Somalia.

The tanker Sirius Star, at three hundred thirty meters long, is the biggest ship ever known to have been captured by pirates. It also happened farther south than most attacks, and farther out at sea ---- more than eight hundred kilometers from land.

The ship was headed for the United States with two million karrels of oil, worth an estimated one hundred million dollars. A Saudi Arabian company owns the tanker. The pirates have  reportedly demanded twenty-five million dollars in negotiations to release the ship and its crew of twenty-five.

Somali pirates generally do not steal goods or kill hostages. They are believed to be holding seventeen ships with about three hundred crew members. Among the ships is a Ukrainian vessel hijacked(劫持) in September with a load of military weapons including tanks.

The increase in piracy is raising the cost of insuring ships. Also, oil from the Middle East and exports from East Asia could take longer to arrive.

Some of the world’s heaviest shipping traffic passes the Somali coast. But major shipping companies have begun to consider new routes. One of the world’s biggest shippers, A.P, Moeller Maersk, says it will avoid the Gulf of Aden. A move away from the Suez Canal could hurt Egypt’s economy.

American and other foreign navy ships are now watching for pirates. This week the Indian Navy destroyed a heavily armed “mother ship” in the Gulf of Aden. But the area to protect covers more than one hundred sixty million square kilometers.

小题1: According to the passage, which of the following is the key to solving the piracy in Somalia?

A.Providing lots of money.

B.Ending Civil war.

C.Supplying enough food.

D.Handling Somalia’s political problems.小题2: Somali pirates do the following things except that _______.

A.they demand money

B.they hold the ships with crew

C.they kill some of the hostages

D.they hijack ships with military weapons小题3:What can we infer from the passage?

A.The cost of ship transport is decreasing.

B.The routes of some ships might change.

C.Nothing has been done to fight against the piracy.

D.The Suez Canal is of no importance to Egypt’s economy.

题型:填空题

不加热集油流程的特点和适用条件。

题型:填空题

卷绕机上分别有()和()(类型)。

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