更多"[单选题]某公司含磷废水的磷酸盐(以P计)浓度为4.0mg/L,为满足"的相关试题:
[单选题]某公司含磷废水的磷酸盐(以P计)浓度4.0mg/L,为满足处理后磷酸盐浓度≤1.0mg/L的要求,污水处理工艺应采取()。
A.化学氧化法
B.化学沉淀法
C.活性污泥法
D.超滤法
[单选题]分光光度法测定洗涤剂中的磷酸盐是要酸的浓度应保持在( )mol/L 。
A.0.1~1
B.0.4~1.4
C.0.5~2.0
D.0.5~1.8
[单选题]静液压力梯度受液体密度、含盐浓度、溶解气体的浓度以及温度梯度的影响。( )
A.正确
B.错误
[填空题]锅炉在运行中排走一部分含盐浓度高的和含水渣浓度大的炉水叫做(),排污量占锅炉蒸发量的百分数称为()。
[单选题]窝沟封闭中酸蚀用磷酸浓度为
A.20%~30%
B.30%~40%
C.40%~50%
D.50%~60%
E.60%~70%
[单选题]酸蚀应用的最合适的磷酸浓度是
A.10%~20%
B.20%~30%
C.30%~40%
D.40%~50%
E.85%
[单选题]在盐浓度为()时多数细菌难以生长繁殖。
A.3%~5%
B.5%~10%
C.10%~15%
D.15%~20%
[不定项选择题]When we analyze the salt salinity (盐浓度) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind ; this, by the way,is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. similarly, in coastal.
Grandma, who used to live upstairs, is now the voice on long distance, and the working parent is far too beaten down each day to spend evening relaxation time listening to the sandbox experience of an eager four-year-old.
So family conversation is as extinct as my old toys and parental questions such as "What have you been doing, Bobby? " have been replaced by "I 'm busy, go watch television.
And watch TV they do; count them by the millions.
But it's usually not children's television that children watch. Saturday morning, the children's hour, amounts to only about 8 percent of their weekly viewing.
Where are they to be found?Watching adult television, of course, from the Match Game in the morning, to the afternoon at General Hospital, from the muggings and battles on the evening news right through the family hour and past into Starsky and Hutch. That's where you find our kids, over five million of them, at 10 p.m., not fewer than a million until after midnight! All of this is done with parental permission.
Television, used well, can provide enriching experiences for our young people, but we must use it with some sense. When the carpet is clean, we turn off the vacuum cleaner. When the dishes are clean, the dishwasher turns itself off.
Not so the television, which is on from the sun in the morning to the moon at night and beyond!
Parents must exercise some control and show some concern about the cultural influence on the child when a program not intended for that child is viewed. Parents need to intervene. Nonintervention may be a wise policy in international affairs, but the results of parental nonintervention will not be wise at alL.
What is the main idea of the last paragraph?
A.Parental nonintervention will not be praised.
B.Nonintervention may be a good policy in international affairs.
C.Parents must exercise some control and show some concern about the cultural influence on the children.
D.Parents need to intervene.
[单选题]新含氢硅油除酸水溶液的盐水浓度控制在?
A.10%左右
B.15%左右
C.20%左右
D.25%
[单选题]下列选项中,()在盐浓度为3%时最宜生长繁殖。
A.霉菌
B.副溶血性弧菌
C.沙门氏菌
D.大肠杆菌
[单选题]窝沟封闭时,酸蚀应用的最佳磷酸浓度是()
A.10%~20%
B.20%~30%
C.30%~40%
D.40%~50%
E.60%以上
[单选题]妊娠妇女血液透析透析液的碳酸氢盐浓度应调整为( )mmol/L。
A.0
B.25
C.30
D.35
E.40
[判断题]定期排污的作用是从锅水表面附近将含盐浓度最大的锅水排( )
A.正确
B.错误