题干

大功率镍氢动力电池及其管理模块,是国家“十五”863计划电动汽车专项中一项重要课题。我国镍氢电池居世界先进水平,解放军潜艇将装备国产大功率镍氢动力电池。常见镍氢电池的某极是储氢合金LaNi5H6(LaNi5H6中各元素化合价均为零),电池反应通常表示为:
LaNi5H6+6NiO(OH)LaNi5+6Ni(OH)2
下列有关镍氢电池的说法,不正确的是

A:电池工作时,储氢合金作负极

B:电池充电时,阳极发生氧化反应

C:电池放电时,电子由正极通过外电路流向负极

D:电池工作时,负极反应式:LaNi5H6 + 6OH- − 6e- ='=' LaNi5 + 6H2O

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C

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    The Women's Institute is urging supermarkets to do more to help consumers reduce their home food waste, after a survey of its own membership showed widespread confusion about “best before” and “use by” labeling(标签) on packaging.

    Its new analysis of products on supermarket shelves found that “once-opened” instructions were often contradictory and often failed to make clear whether they were a guide to food safety or quality. Only 45% of 5,000 WI members surveyed understood that best-before dates were a sign of food quality, while 26% did not understand that the more important use-by dates were a decisive guide to food safety.

    In its report on food waste, the WI said supermarkets were “potentially contributing to home food waste by leading customers to buy more food than they need, and giving conflicting and confusing on-pack information that leaves customers unsure about how long a product remains safe to eat in the home setting”. The 42-page report is part of the WI's ongoing campaign to reduce food waste. To underline the point about conflicting information, it cites(引用) a can of Sainsbury's own-brand sweetcorn advising consumers to eat it within one day of opening, while a similar tin from Waitrose gave consumers two days to finish it. Green Giant sweetcorn, however, has no specified date for eating once opened.

    Marylyn Haines Evans, chair of the Women's Institute's public affairs said: “WI members are some of the more informed members of society about food and cookery, but they are still confused about food labelling and 'once-opened' information. So we would like supermarkets to extend the amount of time that consumers have to use a product in their homes by making all of their once-opened instructions on product packaging consistent, and completely remove once-opened instructions on products where food safety is not an issue.”