水质分析的一般检验项目中,有些项目要求尽快分析,有些项目要求在4小时内测定。下列各项

题型:单项选择题 A1/A2型题

问题:

水质分析的一般检验项目中,有些项目要求尽快分析,有些项目要求在4小时内测定。下列各项检验中,可在4小时之外测定的是()。

A.pH值

B.Hg

C.铬(六价)

D.亚硝酸盐氮

E.氯仿、四氯化碳

考点:理化检验技术(师)专业知识专业知识题库
题型:单项选择题 A1/A2型题

 阅读理解     

     A lot of adults worry that spending too much  time playing video games 

isn't good for a kid's health. But some doctors have noticed that kids who

bring their handheld game players to the hospital seem less worried about

being there. They also seem to have less pain when they are playing games.  

        Some patients must be hooked up to dialysis machines ( 透析器) at

least three hours each time. Doctors allow kids to play online sports,racing,

and other games with each other. "We want to use the power of the Internet

to bring kids together and let them know they are not alone," said the doctor.

He loves video games himself  and got the idea to connect kids all over the

country. 

        Many researchers are testing video programs that might help young

patients. For example,a nine-year-old boy who was struggling with cancer

helped to design avideo game to let players get rid of cancer cells. 

     Doctors already know that reducing pain and worry helps patients heal

 faster.

1. Most adults think that playing video games too much is                

A. good for kid's health      

B. bad for kid's health      

C. good for kid's study      

D. bad for kid's eyes  

2. Some doctors think playing games can help the kids get         hen they are ill in hospital.    

A. more worried and pain    

B.less worried and pain    

C. more care from their parents    

D.less care from the nurse  

3. The Chinese meaning of the underlined phrase " get rid of" is               

A.得到  

B.除掉  

C.关心  

D.放心  

4. The doctors allow these kids to         with each other.      

A. play online games    

B. play cards      

C. sing popular songs  

D. study English  

5. The writer wants to tell us         in this passage.      

A. how to play video games      

B. playing video games can be good to the kids who are ill         

C. adults think it is good for kids to play video games      

D. kids should often play video games

题型:单项选择题 A1/A2型题

如图,一理想变压器的原线圈两端接入电压为的交变电流。原线圈匝数匝,副线圈匝数为匝,则

A.副线圈中磁通量变化率的最大值为V

B.将耐压值为6V的电容器接在两端,能正常工作

C.把额定电压为8V的小灯泡接在两端,小灯泡能正常工作

D.把电磁打点计时器接在两端,打点周期为

题型:单项选择题 A1/A2型题

单相桥式电路整流后直接并-电容滤波,为什么用万用表测电容器两端电压会比测整流前的交流电压还高?

题型:单项选择题 A1/A2型题

装设在变压器中性点的消弧线圈,其补偿方式应为( )。

A.补偿容量应与系统中总的电容量相等;
B.欠补偿;
C.过补偿;
D.只要补偿系数合适,欠补偿和过补偿都可以。

题型:单项选择题 A1/A2型题

什么是测量?什么是热工测量?什么是热工测量仪表?

更多题库