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 Science of Risk-Seeking

    Sometimes we decide that a little unnecessary danger is worth it because when we weigh the risk and the reward, the risk seems worth taking. ____ Some of us enjoy activities that would surprise and scare the rest of us. Why? Experts say it may have to do with how our brains work?

    The reason why any of us take any risks al all might have to do with early humans. Risk-takers were better at hunting, fighting, or exploring. ____ As the quality of risk-taking was passed from one generation to the next, humans ended up with a sense of adventure and a tolerance for risk.

    So why aren't we all jumping out of airplanes then? Well, even 200,000 years ago, too much risk-taking could get one killed. A few daring survived, though, along with a few stay-in-the-cave types. As a result, humans developed a range of character types that still exists today. So maybe you love car racing, or maybe you hate it. ____

    No matter where you are on the risk-seeking range, scientists say that your willingness to take risks increases during your teenage years. ____ To help you do that, your brain increases your hunger for new experiences. New experiences often mean taking some risks, so your brain raises your tolerance for risk as well.

    ____ For the risk-seekers a part of the brain related to pleasure becomes active, while for the rest of us, a part of the brain related to fear becomes active.

    As experts continue to study the science of risk-seeking, we'll continue to hit the mountains, the waves or the shallow end of the pool.

A. It all depends on your character.

B. Those are the risks you should jump to take.

C. Being better at those things meant a greater chance of survival.

D. Thus, these well-equipped people survived because they were the fittest.

E. This is when you start to move away from your family and into the bigger world.

F. However, we are not all using the same reference standard to weigh risks and rewards.

G. New brain research suggests our brains work differently when we face a nervous situation.