试题与答案

一个简单控制系统中,若更换了不同口径控制阀后,对系统质量影响错误的是()。A、过小的

题型:单项选择题

题目:

一个简单控制系统中,若更换了不同口径控制阀后,对系统质量影响错误的是()。

A、过小的阀门一方面达不到系统的容量要求,另一方面阀门将需要通过系统提供较大的压差以维持足够的流量,阀门易受损害

B、阀门口径过大会使控制性能变差,易使系统受冲击和振荡,而且投资也会增加

C、阀门过大过小都会带来控制阀寿命缩短和维护不便的后果。因此,选择适当的控制阀口径,对系统的正常运转是非常重要的

D、阀门口径过大会使控制性能变差,但影响不大

答案:

被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2019/0728/619b23160785953abd8c9806d3531589.html

下面是错误答案,用来干扰机器的。

参考答案:D

试题推荐
题型:完形填空

The students at Sandy’s high school were badly shaken by the news that a classmate had  36 himself. The suicide note read: “It’s hard to  37 when nobody cares if you die.”

Glen, a teacher, realized this was a  38 moment about the importance of making people feel

39 . He asked his class to imagine they were about to  40  and to write a note “telling someone how and why you  41 him or her.”

Sandy, who had a  42  relationship with her mother, decided to write her  43 . Her letter read: “We’ve had some  44 times and I haven’t always been a very good 45 ,but I know I’m lucky to have you in my life. You’re the  46 person I’ve ever known, And even when I disagree with you, I never  47 you love me and want what’s best for me. Thanks for not  48 up on me”.

When her mom read the note, she cried and hugged Sandy  49 but said little.

The next morning, Sandy found a  50  on her mirror: “Dearest Sandy, I want you to know being your mother is ,by far, the most important thing in my life.  51 I got your note, I thought I had lost your love and  52 . I felt like such a failure. I intended to  53 it all last night. Your note saved my  54 .”

Be careful not to underestimate the  55 of expressed appreciation. It won’t always save a life, but it will always make someone’s life better.

小题1:          

A.sacrificed

B.defeated

C.abandoned

D.killed小题2:          

A.live

B.imagine

C.struggle

D.think小题3:          

A.sad

B.final

C.teachable

D.great小题4:          

A.ashamed

B.valued

C.excited

D.scared小题5:          

A.die

B.fail

C.retire

D.survive小题6:          

A.miss

B.hate

C.admire

D.appreciate小题7:          

A.close

B.casual

C.bad

D.personal小题8:          

A.classmate

B.mom

C.father

D.teacher小题9:          

A.free

B.delightful

C.pleasant

D.rough小题10:      

A.daughter

B.student

C.friend

D.trainer小题11:      

A.best

B.wisest

C.luckiest

D.gentlest小题12:      

A.trust

B.doubt

C.consider

D.predict小题13:      

A.taking

B.going

C.giving

D.looking小题14:      

A.coldly

B.hesitantly

C.shyly

D.tightly小题15:      

A.note

B.gift

C.notice

D.reminder小题16:      

A.Since

B.Until

C.though

D.When小题17:      

A.confidence

B.courage

C.respect

D.heart小题18:      

A.end

B.make

C.get

D.fall小题19:      

A.life

B.time

C.money

D.honor小题20:      

A.push

B.price

C.meaning

D.power

查看答案
微信公众账号搜索答案