问题 问答题 简答题

在QXZ型气动色带提示仪中,阻尼阀与反馈气室组成什么环节?作用是什么?在显示锅炉水位中,阻尼阀开度大小的依据是什么?

答案

参考答案:

阻尼阀与反馈气室组成一阶惯性环节,对测量信号的变化起阻尼延时作用,以防止指示仪指针振荡,在显示锅炉水位中,调整阻尼阀的开度,使惯性环节的时间常数T接近于船舶的摇摆周期。

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Street Markets(市场) around the World
There are many ways of shopping. You can shop by telephone, by post or through your home computer. But for many people, the most exciting way to shop is also the most traditional(传统的)—at a street market. You can find markets anywhere in the world. Here are four of them:

There are many “floating markets” in Asia; maybe the most unusual is in Thailand(泰国), at a place called Damnoen Saduak. It’s open from six in the morning to the noon every day. People sell fresh apples, bananas and things like these from their boats.

Many Belgians(比利时人) say that the Grand Place is the most beautiful place in the world. It is the home of a colourful market. It’s open every day except(除了) Monday. On Monday, there’s a wonderful bird market!

One of the world’s most famous markets is in Mexico City—the Sonora Market. You can buy toys, birds and anything you need. It’s open every day from early in the morning till late at night.

In London, on Saturdays and Sundays, thousands of young people from all over the city travel to the Camden Market. It’s the place to go for street fashion, CDs and tapes. Many people also go there for fun.
 
Names
 Countries
Features(特色)
Things to Sell
Open Time
The Damnoen Saduak
Thailand
unusual
fresh    1  
every day
The Grand Place
Belgium
   2  
flowers
every day except Monday
The Sonora Market
Mexico
famous
all    3   of things
every day
The Camden Market
   4  
fashionable
street fashion, CDs and tapes
every    5