在大电流接地系统中发生单相接地故障,从录波图看,该故障相电流有畸变,请问是否可以直接

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问题:

在大电流接地系统中发生单相接地故障,从录波图看,该故障相电流有畸变,请问是否可以直接利用对称分量法进行故障分析,为什么?

考点:继电保护工考试继电保护高级工继电保护高级工题库
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阅读理解。

     Tea bag drinking is most Westerns' favorite way of drinking tea. Do you know how it came about?

     The tea bag was invented in 1908 by Thomas Sullivan, an American tea seller. He was sending out free

tea in silk (丝绸) bags for people to try. People put the bags together with the tea leaves into the cup and

added hot water. The tea tasted good, and people thought it was easy to clean the cup. They were not happy

when Sullivan started sending them loose (散的) tea again.

     Sullivan realized that he had a hot new thing in his hands, and he built a machine to pack the bags. As tea

bags became popular, they were changed from silk to gauze (薄纱) and later paper. In 1952, Lipton Tea

made the tea bag even more popular with its invention of the four-sided tea bag. Tea bags were soon a hit

in the UK, and today 85% of the tea in the UK is packed in paper bags.

     However, many people still prefer loose-leaf tea. This is because some tea companies put not very good

tea in their tea bags. But for most drinkers, tea bags are still the easy, tasty way to go.

1. Who invented the tea bag?

A. An English tea seller.

B. Chinese.

C. Lipton.

D. Thomas Sullivan.

2. The tea in silk bags was welcome because ________.

A. the tea in bags was free and very good

B. the tea tasted good and the cup was easy to wash

C. people were happy with the loose tea

D. people didn't know any better way to enjoy the tea

3. The material of the tea bags is usually ________ now.

A. silk

B. gauze

C. paper

D. plastic

4. The underlined sentence "Tea bags were soon a hit in the UK" probably means"________ in the UK".

A. Tea bags soon became popular

B. Tea bags surprised everyone very much

C. Tea bags kicked (踢) the loose-leaf tea out of the market

D. Tea bags weren't allowed to be sold

5. The reading mainly talks about ________.

A. the invention of tea

B. the way of drinking tea

C. the history of tea bags

D. people's favorite tea in the world

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男性,40岁,有胃痛史多年,并向腰背部放射疼痛,经内科药物治疗效果不显著,经胃镜检查诊断为胃角后壁溃疡,向胰腺穿透,病理检查排除癌肿,首选手术方式

A.选择性迷走神经切断术

B.毕I式胃大部切除术

C.毕Ⅱ式胃大部切除术

D.胃大部切除术,溃疡旷置

E.胃空肠吻合术

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不能避免和减轻外来打击的防冲击用品的是()。

A、安全绳

B、安全网

C、安全带

D、安全帽

题型:问答题 简答题

一定量的理想气体,处在某一初始状态,现在要使它的温度经过变化后又回到初始状态,下述过程中可能实现的是(  )

A.先保持体积不变而减小压强,接着保持压强不变而使体积增大

B.先保持体积不变而增大压强,接着保持压强不变而使体积增大

C.先保持压强不变而减小体积,接着保持体积不变而使压强增大

D.先保持压强不变而增大体积,接着保持体积不变而使压强减小

题型:问答题 简答题

以下哪种因素与牙周病关系不大()

A.银汞合金充填体有悬突

B.牙齿排列不齐

C.嗜甜食

D.冠修复体不良

E.大量牙石

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