电阻丝式应变片与半导体应变片在工作原理上有何不同？各有何优缺_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题问答题简答题

电阻丝式应变片与半导体应变片在工作原理上有何不同？各有何优缺点？

答案

参考答案：

金属电阻应变片是利用电阻应变效应；半导体应变片是利用压阻效应。电阻丝应变片利用导体形变引起电阻变化，半导体应变片利用半导体电阻率变化引起电阻变化。通常半导体应变片比电阻丝应变片灵敏度高，但分散性大，温度效应也比较大。

完形填空

Jack Baines is a self-made millionaire, but his beginnings were very lowly. He was the youngest of eight children. His father had a 16 in a cotton mill (纱厂), but he was often 17__ to work because of poor health. The family couldn’t afford to pay the rent or bills, and the children often went hungry. After leaving school at the age of 14, Jack was 18 what to do when Mr. Walker, his old teacher, offer

ed to lend him ￡100 to start his own __19__ .
It was just after the war. Raw materials were not enough, and Jack saw a 20 in scrap metal(废弃金属). He bought bits of metal and stored it in an old garage. When he had built up a large amount, he sold it and 21 plenty of money.
Jack 22 working hard. After one year he succeeded in repaying the ￡100.
By the

time Jack was 30 years old he had 23 his first million, and he wanted to 24 this achievement by doing something “grand”. 25 _ all his money it was possible to build a beautiful home for himself and his parents. In 1959, “Baines Castle” was built in the heart of the Lancashire countryside. It was one of the finest buildings in the country.
Jack has recently sold “Baines Castle” for ￡500 million, 26 Jack still can’t get used to 27 the good life. He can often _28_ drinking with the locals at the local pub.
“I remember being very 29 as a child, but never 30 as a child,” says Jack, “and I will never forget where I came from and who I am.”

D．be looked for

单项选择题

选择免疫组织化学染色方法最重要的原则是（）

A.安全性

B.简便性

C.特异性

D.敏感性

E.费用低廉