比转数较小的水泵,其叶轮流道形状() A.短粗 B.狭长

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问题:

比转数较小的水泵,其叶轮流道形状()

A.短粗

B.狭长

考点:污水处理工考试污水处理高级工考试污水处理高级工考试题库
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To get a chocolate out of a box demands a considerable amount of unpacking: the box has to be taken out of its paper bag; the plastic wrapper has to be torn off, the lid opened and the packing paper inside removed; the chocolate itself then has to be unwrapped from its own piece of paper. Similarly a pot of face cream comes surrounded by layers of paper, waged inside a cardboard box, and the whole thing wrapped tightly in plastic.
It is not only luxuries which are wrapped in this way, With so many goods now produced centrally and sold in supermarkets it is becoming increasingly difficult to buy anything from nails to potatoes that is not already done up in plastic or paper.
The wrapper itself is of no interest to the shopper, who usually throws it away immediately. Useless wrapping accounts for much o the 31 pounds in weight of rubbish put out by the average London household each week. So why is it done Some of it, like the wrapping on meat, is necessary, but most of the rest is simply competitive selling. This is stupid. Packaging is using up scarce energy and raw materials and ruining all the time. One big firm reports that its glass, cans and paper have all gone up by 30 per cent in the last couple of months, while plastic has increased by 50 percent and all these prices are still rising. This seems as yet to have had surprisingly little effect on the packaging practice of manufacturers.
Little research is being carried out on the costs in energy and materials of other possible types of packaging. Just how practical is it, for instance, for local authorities to save waste paper and re-manufacture it as egg-boxes Would it be cheaper to plant another forest to produce new paper
One reason for the unorganized behavior of everyone concerned is probably the varied nature of the packaging industry. So many people, with so many different interests of their own, are affected that it is extremely hard to reach any agreement on what should be done. Also, packagers say that preserving forests and preventing waste is not their concerns.

According to the author, the packaging industry is_______.
A. full of capable people. B. rather disorganized.
C. very worried about waste. D. full of people with different opinions.

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正常尿沉渣镜检,一般可见()

A.结晶

B.细胞管型

C.透明管型

D.白细胞

E.柱状上皮细胞

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人力资源成本核算有哪些方法?

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混凝土自高处向模板内直接倾斜时,其自由倾落高度不宜超过( )。

A.1.0m
B.2.0m
C.0.5m
D.10m

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统计方法的用途有哪些?

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