592. Many industrialized nations are trying toreduce atmospheric concentrations of carbon dioxide, a gas released by theburning of fossil fuels. One proposal is to replace conventional cement, whichis made with calcium carbonate, by a new “eco-cement.” This new cement, madewith magnesium carbonate, absorbs large amounts of carbon dioxide when exposedto the atmosphere. Therefore, using eco-cement for new concrete buildingprojects will significantly help reduce atmospheric concentrations of carbondioxide. Which of the following, if true, most strengthensthe argument? (A) The cost of magnesium carbonate, currentlygreater than the cost of calcium carbonate,probably will fall as more magnesium carbonate isused in cement manufacture. (B) Eco-cement is strengthened when absorbed carbon dioxide reacts with the cement. (C) Before the development of eco-cement,magnesium-based cement was considered too susceptible to water erosion to be of practicaluse. (D) The manufacture of eco-cement usesconsiderably less fossil fuel per unit of cement than the manufacture of conventional cement does. (E) Most building-industry groups are unaware ofthe development or availability of eco-cement.
这题答案选D,楼主选了B
题干里面说eco-cement可以吸收二氧化碳,楼主第一反应就是这种吸收会不会产生不良反应。如果有不良反应不就玩完了。结果看到B选项,正合我意。
作为减排来讲,D确实是正确的,因为在生产环节进一步减少了排放量。但是作为建筑材料来讲,肯定不应该先看他在第一环节能否使用吗?然后才能谈生产环节的事情。如果他本身吸收carbon dioxide之后的反应都不明,这逻辑链在这里就直接断掉了。如果有不良反应,按D说制造再多的eco-cement都是浪费。
所以楼主很费解。至少楼主如果是新闻发言人,绝对会在eco-cement会吸收carbon dioxide之后补一句,这种吸收是有益的。不知各位大神有何看法?
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