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问题 问答题 简答题

平原河流河床均由什么泥沙组成，是否易于冲刷？

答案

参考答案：

平原河流河床均由细粒泥沙组成，极易冲刷。

单项选择题

①垃圾处理愈来愈成为现代社会亟待解决的社会问题。未来的垃圾处理将从地面转入地

下——也就是说，利用地下的空间，建立垃圾输送管线网，用压力密封输送的方法将垃圾运送到设置在地下的垃圾焚烧装置中进行处理，并可利用焚烧垃圾的热量获得热水，再通过地下管道网络向千家万户提供热能。

②如果把实用化算作100的话，那么目前的开发研究只处于10的起步阶段，预计到2022年才能实现实用化。当今国际上对该技术的研究，日本刚刚开始，而美国、欧洲尚未起步。

③预计到2020年实用化时，垃圾地下处理系统的市场规模约300亿日元。垃圾地下处理系统的实用化，将给供热产业——焚烧生产厂的发展注入活力，还会给空调设备生产业、建筑产业、管道生产业和运输产业带来有利影响，但是它将对电力和燃气产业构成竞争。

④要使垃圾地下处理系统实用化，需解决一系列难题：例如低成本的地下掘进技术，特别是管网的铺设技术；密封输送技术，贮热、输热技术；复合焚烧炉的研究等。除此之外，还需要国家制定一系列相应的政策支持推进该项技术。

文中第③段中加点字“它”所指代的内容是（）。

A．垃圾地下处理系统

B．市场规模

C．垃圾地下处理系统的实用化

D．垃圾地下处理系统的市场规模
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填空题

Facts about Aging


The overall difference in life expectancy at birth in the United States is about 7 years (i.e.72 for men vs. 79 for women); and at every age women, on average, can expect to live longer than men. Interestingly, older women are more likely to suffer from debilitating illnesses than men. However, this difference seems to reflect the fact that women typically have less wealth and education than men - two factors that are associated with shorter life expectancies for both sexes. When the effects of poverty and education are removed in the relevant statistical analyses, these sex differences in rates of disability disappear.
The elderly generally show very high interest in associating with friends and close family members. What they show less interest in than younger adults is the expansion of their social networks to make new friends.
About one-third of problem drinkers develop their alcohol abuse problem late in life, and this problem of alcoholism among the aged is indeed more acute for women than men. Overuse of drugs may result from the tendency of some doctors to automatically prescribe drugs rather than search for underlying physical or psychological causes of symptoms, especially when the patients are elderly women. It may also reflect the fact that women are more likely to be facing the loneliness and stress associated with the loss of a spouse than men, and are generally more likely to seek help from a doctor.
Alzheimer’s disease, the much-dreaded form of dementia associated with profound memory loss and other increasingly devastating symptoms, is a condition that strikes a significant number of elderly people. Nevertheless, most elderly people will never suffer such memory loss. In fact, contemporary estimates suggest that moderate to severe memory loss is found in only 4 to 6 percent of adults over age 65. The most important point to be aware of is that while memory (especially short term memory) does deteriorate somewhat as we get older, profound memory loss is not a "natural" consequence of the aging process. It is a product of disease. Evidence of profound memory loss should prompt a visit to a physician who specializes in such problems.
after age 80 the ratio of widows to widowers in the U.S. is about 5 to 1. This statistic reflects the fact that women have a longer life expectancy than men, and the fact that women typically marry men older than themselves. Differences in wealth may also make it easier for marriage-minded widowers to find mates than widows, since elderly women are more likely to be living in poverty than elderly men.
The stereotype of depressed lonely old people is a pervasive one, but it is not supported by the facts. While social isolation is a problem for many older people, it is also a problem for many young people as well. Surveys consistently show that, in the absence of serious illness, older people generally report higher levels of happiness or life satisfaction than young people. One reason for this is that as people age they seem to devote increasing attention to the task of managing their affective states and avoiding sadness or anxiety.
Although there is considerable variability in the degree of loss, sensory decline is fairly inevitable. These losses, it should be noted, have important implications for environmental design in the care of the elderly. For example, greater use of acoustical tile to absorb background noise, use of non-slippery floor surfaces to provide additional traction, and use of non-glare surfaces and clearly marked boundaries can all increase comfort and safety.

The author’s tone about aging is
A. humorous. B. objective.
C. doubtful. D. negative.
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