题干

下列有关反应速率的说法中,正确的是(   )

A:合成氨过程是一个放热反应,所以升高温度,反应速率反而减小

B:等质量的镁粉和镁条与同体积、同浓度的稀硫酸作用,其反应速率相等

C:铝片与硫酸溶液反应可产生氢气,常温下用98%的浓硫酸可以加快生成氢气的速率

D:同温同体积时,浓度大的草酸溶液比浓度较小的使酸化高锰酸钾溶液褪色速度快

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D

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How northern Europeans beat the winter blues

    Ask a child from northern Europe to draw two pictures—one on a rainy day and a second in the sunshine—and this is what you will get: in the first, as raindrops fall from the top of the page, the man behind the window has an unhappy expression. When a yellow sun sends out some light from the corner, the man is smiling.

    Northern Europeans associate rain with sadness and sunshine with happiness. They think this is true because they are so aware of how their environment affects them____In October 2008, a group of researchers examined the influence of different daily weather factors, including temperature,wind and sunlight, on 1,200 participants. The conclusion was that good or bad weather had little effect on people's feelings____ A person who is upset on dark or cold days suffers from a negative mood, and he will be likely to experience a sad winter. This is the basis of an illness called Seasonal Affective Disorder (SAD)____ 

    AniKalayjian, professor of psychology at Fordham University, advises that we should take steps to strengthen the brain's system against weather-driven mood changes. Research on SAD has been focused on the brain's response to darkness and light. When our eyes detect darkness, the brain gives off melatonin, which starts sleep cycles____ It takes over to help us wake up and feel better when we detect light.“We can encourage people to take charge of their feelings,” says Kalayjian.“We tell them to leave the computers and the indoor games and get out there in the sun____”

    A day of rain can potentially destroy your plan and affect your mood. But as the Scottish comedian Billy Connolly once said:“There is no such thing as bad weather, only the wrong clothing.”

A. Another chemical called serotonin, however, can make people happy.

B. It affects about10% of the population of northern Europe each year.

C. That's when people can recharge their serotonin and get a better mood.

D. Yet that link has no scientific basis.

E. Most studies prove that a negative feeling is associated with bad weather.

F. They determined that people actually differ in their sensitivity to weather changes.

G. It is seriously doubted among the people who suffer from SAD.