用经验法整定调节器参数时,如果记录曲线不规则变化,记录曲线振荡呈锯齿形或阶跃变化等波

题型:单项选择题

问题:

用经验法整定调节器参数时,如果记录曲线不规则变化,记录曲线振荡呈锯齿形或阶跃变化等波形,这是由于()原因引起的。

A.参数整定不合理

B.仪表或调节阀

C.对象前工序

D.对象本身

考点:仪表工考试中级仪表工中级仪表工题库
题型:单项选择题

下列叙述中正确的是[ ]

A.某醋酸溶液的pH=a,将此溶液稀释1倍后,溶液的pH=b,则a>b

B.在滴有酚酞溶液的氨水里,加入NH4Cl至溶液恰好无色,则此时溶液的pH<7

C.1.0×10-3 mol·L-1盐酸的pH=3.0,1.0×10-8 mol·L-1盐酸的pH=8.0

D.若1 mL pH=1的盐酸与100 mL NaOH溶液混合后,溶液的pH=7,则NaOH溶液的pH=11

题型:单项选择题

统计方法是以()来解释规律的方法。

题型:单项选择题

根据下面对话中的情景,在每个空白处填入适当的语句,使对话恢复完整。

A:Excuse me,may I ask you some questions?

B:Sure,please.

A:1_______        

B:I drink milk every day.

A:Do you like it?

B:2_______But Mom wants me to drink it. She says milk is good for my health.

A:How about junk food?

B:3_______  But I try to eat it only once or twice a week. You know,it 'tastes good, but it's not good for our health.

A:That's right. Do you like vegetables and fruit?

B:4_______ I eat them nearly every day. My favorite vegetable is broccoli;my favorite fruit is apples?

A:As for sleeping,5_______                   

B:About eight or nine hours. 

A:Do you sleep well?

B:Yeah,very well. 

A:Oh,your lifestyle is really good. I think you must be in good health.

B:You're right.

题型:单项选择题

股票这种有价证券从性质来看有()的性质。

A、要式证券

B、设权证券

C、证权证券

D、资本证券

题型:单项选择题

肛裂发生原因为()

A.直肠镜检查引起肛管表浅皮肤裂开 

B.粪便干硬 

C.肛窦炎致肛管皮下脓肿破溃 

D.肛管皮肤较薄 

E.排便用力过锰,肛管受到较深的裂伤

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