问题 单项选择题

属于塑性体沥青防水卷材的是( )。

A.APP改性沥青防水卷材

B.SBS改性沥青防水卷材

C.沥青复合胎柔性防水卷材

D.三元乙丙橡胶防水卷材

答案

参考答案:A

解析:[考点] 第二章工程材料第四节防水材料中刚性防水材料的性质。[思路] 聚合物改性沥青防水卷材包括SBS改性沥青防水卷材、APP改性沥青防水卷材和沥青复合胎柔性防水卷材,其中,SBS改性沥青防水卷材属弹性体沥青防水卷材,APP改性沥青防水卷材属于塑性体沥青防水卷材。[易错] B,选错的原因是把APP改性沥青防水卷材和SBS改性沥青防水卷材的性质记混淆了。[拓展] 关于合成高分子防水卷材。 (1)合成高分子防水卷材是以合成橡胶、合成树脂或它们两者的共混体为基料,加入适量的化学助剂和填充料等,经混炼、压延或挤出等工序加工而制成的可卷曲的片状防水材料; (2)其特点是:具有拉伸强度和抗撕裂强度高,断裂伸长率大,耐热性和低温柔性好,耐腐蚀,耐老化等一系列优异的性能,是新型高档防水材料; (3)包括:三元乙丙(EPDM)防水卷材、聚氯乙稀(PVC)防水卷材、氯化聚氯乙稀防水卷材和氯化聚氯乙稀—橡胶共混型防水卷材等。

单项选择题

完形填空:下面的短文有l5处空白,请根据短文内容为每处空白确定l个最佳选项。

Obesity(肥胖) Causes Global Warming.

The list of ills attributable to obesity keeps growing: Last week, obese people were accused of causing global warming.

This ______(51)comes from Sheldon Jacobson of the University of Illinois, US, and a doctoral student, Laura McLay. Their study ______(52) how much extra gasoline is needed to haul fat Americans around. The answer, they say, is a billion gallons of gas per year. ______(53)

There has been ______(54) for taxes on junk food in recent years. US economist Martin Schmidt suggests a tax on fast food ______(55)to people’s cars. "We tax cigarettes partly because of their health cost," Schmidt said. "Similarly, leading a lazy life style will end ______(56) costing taxpayers more."

US political scientist Eric Oliver said his first instinct was to laugh at these gas and fast food arguments. But such ______(57) are getting attention.

At the US Obesity Society's annual meeting, one person ______(58) obesity with car accident deaths, and another correlated obesity with suicides. No one asked whether there was really a cause-and-effect relationship. " The funny thing was that everyone took it ______(59)." Oliver said.

In a 1960s study, children were ______(60) drawings of children with disabilities and without them, and a drawing of an obese child. They were asked ______(61) they would want for a friend? The obese child was picked last.Three researchers recently repeated the study ______(62) college students. Once again, ______(63) no one, not even obese people, liked the obese person. " Obesity was stigmatized." the researchers said.

But, researchers say, getting______ (64) is not like quitting smoking. People struggle to stop smoking, and, in the end, many succeed. Obesity is different. Science has shown that they have limited personal control over their weight Genes also______ (65) a part.

54.(单项选择题)        

A.calls

B.cries

C.sounds

D.noises

单项选择题