问题 综合

( 10 分)【环境保护】降水中的化学元素成分往往是衡量大气质量的标准之一。其中地壳元素(AI \ K \ Ca\ Mg )主要来源于沙尘基和扬尘,重金属(Zn \ Mn \ Ba \ Pb)主要来源于冶炼、燃煤和汽车尾气。下图为我国北方某城市降水中元素浓度的季节变化统计图。阅读图文,回答下列各题。

( l )依据材料分析,图中该市降水中的化学元素浓度季节差异。 ( 4 分)

( 2 )依据所学知识.分析上题中产生季节差异的原因。( 6 分)

答案

(1)差异:城市降水中化学元素浓度冬春季比夏秋季节高;春季、冬季,地壳元素含量较高;从重金属含量看,在冬季含量明显较高。(任答二点,得4分)

(2)原因:我国北方,冬季降水少,夏秋季节降水多,浓度低;春季沙尘暴天气、扬尘天气多,大气中沙尘颗粒多,空气中化学元素含量高;我国北方冬季燃烧煤取暖较多,排放烟尘多,从而重金属含量高;冬季气温低,大气相对稳定,多逆温天气,不利于扩散。(任答三点,得6分)

题目分析:

(1)从图形中可以直接得出:城市降水中化学元素浓度冬春季比夏秋季节高;从地壳元素看春季、冬季含量较高;从重金属含量看,冬季含量明显较高。

(2)其原因主要从降水量得多少和污染物的多少有关。①我国北方,冬季降水少,浓度高;夏秋季节降水多,浓度低。②春季沙尘暴天气、扬尘天气多,大气中沙尘颗粒多,空气中化学元素含量高;我国北方冬季燃烧煤取暖较多,排放烟尘多,从而重金属含量高;冬季气温低,大气相对稳定,多逆温天气,不利于扩散。

阅读理解

阅读理解。

     The widespread number of food scandals (丑闻) in China is making many people pause before they put

their chopsticks in their mouth. They are wondering if the food they are eating is clean, healthy and nutritious

or does it contain something harmful that will cause disease?

     Most of the food we eat today is processed food ( 加工食品). That means the foods we buy in stores and

supermarkets, especially packaged foods, are prepared in factories. Chemicals are added to the foods in these

factories to make them look better, taste better and last longer on the shelf. The chemicals are supposed to be

harmless and there are laws that regulate which chemicals can and cannot be used. Unfortunately, some

producers do not obey the laws.

     A producer of steamed buns (馒头) in Zhejiang Province was recently discovered to be breaking the law.

He was adding yellow dye and other banned chemicals to the buns. He was also taking old buns and using

them to make new buns. Most of the buns were sold to schools and eaten by students... like you.

     Why did he do it? Why did he break the law and endanger people's health? The answer is simple: he

wanted to make more money. It was a moral failing, and this is at the heart of the food scandals in China.

Too many people focus on making money and not on the effects their actions can have on others.

1. Chemicals are added to the foods in the factories because ________.

A. they want to make the foods look better, taste better and last longer

B. they want to make the foods contain something harmful

C. chemicals will cause disease

D. chemicals are harmless

2. According to the passage, which is NOT true?

A. Most of the food we eat today is prepared in factories.

B. There are laws that regulate which chemicals can and cannot be used.

C. The food scandals in China are making many people worry about the food safety.

D. Most of the buns were sold to schools and eaten, by students in Zhejiang Province.

3. It was a moral failing, and this is at the heart of the food scandals in China.

    Here what's the Chinese meaning of "moral failing"?

A. 精神崩溃

B. 道德滑坡

C. 质量下降

D. 心理失衡

4. What is the main reason of the food scandals in China?

A. Some producers do not obey the laws.

B. The processed food is clean, healthy and nutritious.

C. Too many people pay much attention to making money.

D. The chemicals are supposed to be harmless and can be used.

单项选择题