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【单选题】
The fridge is considered a necessity. It has been so since the 1960s when packaged food first appeared with the label: 'store in the refrigerator. ' In my fridgeless Fifties childhood, I was fed well and healthily. The milkman came daily, the grocer, the butcher, the baker, and the ice-cream man delivered two or three times a week. The Sunday meat would last until Wednesday and surplus bread and milk became all kinds of cakes. Nothing was wasted, and we were never troubled by rotten food. Thirty years on, food deliveries have ceased, fresh vegetables are almost unobtainable in the country. The invention of the fridge contributed comparatively little to the art of food preservation. A vast way of well-tried techniques already existed--natural cooling, drying, smoking, salting, sugaring, bottling... What refrigeration did promote was marketing--marketing hardware and electricity, marketing soft drinks, marketing dead bodies of animals around the globe in search of a good price. Consequently, most of the world's fridges are to be found, not in the tropics where they might prove useful, but in the wealthy countries with mild temperatures where they are climatically almost unnecessary. Every winter, millions of fridges hum away continuously, and at vast expense, busily maintaining an artificially-cooled space inside an artificially-heated house--while outside, nature provides the desired temperature free of charge. The fridge's effect upon the environment has been evident, while its contribution to hu- man happiness has been insignificant. If you don't believe me, try it yourself, invest in a food cabinet and turn off your fridge next winter. You may miss the hamburgers, but at least you will get rid of that terrible hum. Why does the author say that nothing was wasted before the invention of fridges?
A.
People would not buy more food than was necessary.
B.
Food was delivered to people two or three times a week.
C.
Food was sold fresh and did net get rotten easily.
D.
People had effective ways to preserve their food.
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【单选题】防护栏杆由横杆及立柱组成。横杆 2 ~ 3 道,下杆离地高度 0.3 ~ 0.6 米,上杆离地高度 1.0 ~ 1.2 米;立柱间距不大于( )米,立柱离坡边距离应大于 0.5 米。防护栏杆外放置有砂、石、土、砖、砌块等材料时尚应设置扫地杆。
A.
1
B.
2
C.
3
D.
3.5
【简答题】[CoCl2(H2O)4]Cl 的中心离子是 ,配位体是 ,配位原子是 ,配位数是 。
【简答题】配位化合物[Co(NH 3 ) 4 (H 2 O) 2 ] 2 (SO 4 ) 3 的内界是 ,配位体是 和 ,配位原子是 和 ,配位数为 ,配离子的电荷是 。该配位化合物的名称是 。
【多选题】下列有关包装操作,表述正确的是()
A.
待用分装容器在分装前应当保持清洁,避免容器中有玻璃碎屑、金属颗粒等污染物
B.
包装前应当对电子读码机、标签计数器等装置的功能进行检查,确保其准确运行,此类检查不需要记录
C.
有数条包装线同时进行包装时,应当采取隔离或其他有效防止污染、交叉污染或混淆的措施
D.
因包装过程产生异常情况而需要重新包装产品的,必须经专门检查、调查并由制定人员批准
【判断题】配体 的配位原子是H, 的配位原子是O。
A.
正确
B.
错误
【简答题】[CO(NH 3 )3(H 2 O)]Cl 2 的名称是 ,其中心原子为 ,配位体 ,配位数 ,配位原子 。
【简答题】配合物 [Co(NH 3 ) 4 (H 2 O) 2 ] 2 (SO 4 ) 3 的内界是 ,外界是 ,配位体是 ,配位原子是 ,中心原子的配位数是 。
【简答题】[Co(NH 3 ) 3 (H 2 O)Cl 2 ]Cl 的中心离子是 配位体是 ; 配位原子是 ;配位数是 ;该配合物的系统命名为
【简答题】配位化合物 [Co(NH 3 ) 4 (H 2 O) 2 ]Cl 3 的内界是 ,外界是 ,配体是 ,配位原子是 ,中心原子的氧化数为 ,配位数是 。
【简答题】配位化合物 [Cr(NH 3 ) 3 (H 2 O) 2 ] Cl 3 的内界、外界分别为?其中 配体是? 中心原子或离子是? 中心原子的氧化数是? 中心原子的配位数是多少?
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