字神帝國英語天地

今日主題：Sunlight Activates Smog-Causing Chemicals in City Grime 陽光可激活城市灰塵裡引發霧霾的化學物質

托福聽力最好的課外教材：60-Second Science
康康精選托福會考的主題，堅持每天精聽一定會進步的哦!!

​​​​​​​ 建議方法：
1. 先聽兩三遍(不看文稿)
2. 再一句一句聽寫
3. 最後check文稿，看哪聽不出來，是單字沒背過，還是單字發音不熟。
4. 堅持天天聽，就能每天進步哦。

​​​​​​​ MP3音檔：喜歡的同學，幫忙推或按讚哦~~
http://bit.ly/1M5C0QM

​​​​​​​ 只有音檔怎夠，聽不懂地方，不用怕，康康幫你準備好中英文稿了：

​​​​​​​ 中英文稿：

In recent years big cities have seen lower rates of grime. But there's still plenty of grime. Combustion from cars, factories and fires spews out nitrogen oxides. Those compounds react with sunlight and air to form ozone—the main ingredient in smog. And certain nitrogen oxides called nitrates—same stuff you find in fertilizer—also settle onto buildings and other city surfaces. Scientists figured that was the end of the story.
最近大城市的灰塵已經減少了不少。但是，還是有不少塵垢：汽車，工廠和燃燒活動噴射出的氮氧化物。這些化合物在陽光和空氣的作用下，會形成臭氧——霧霾的 主要成分。而某種被稱為硝酸鹽的氮氧化合物—— 你會發現和化肥成分相同——建築物和其它城市地面的成分裡也有。科學家們指出這就是問題所在了。

「Usually one thinks about pollutants such as nitrogen dioxide and nitrous acid as being lost from the atmosphere onto surfaces.」 University of Toronto chemist Jamie Donaldson, at a meeting of the American Chemical Society in Boston on August 17th. 「What we have been interested in is to see whether or not the influence of sunlight on urban grime material can in fact recycle these compounds and bring them back into active play in the atmosphere.」
「通常人們想到的污染物，如二氧化氮和亞硝酸等，正從大氣中流失進入建築物表面。」多倫多大學的化學家Jamie Donaldson，在8月17日波士頓舉行的美國化學協會會議上說到。 「我們感興趣的是陽光是否能影響城市霧霾物質，使這些化合物再次循環並把它們送入大氣中。」

Donaldson and his team found that sunlight interacts with nitrates stuck in grime, kicking them back into the air, where they can contribute to smog. They verified that process by putting trays of glass balls—a proxy for window glass, but with more surface area—out in downtown Toronto, and Leipzig, Germany. The glass in sunny areas lost 10 percent more nitrogen compounds than did their shady counterparts.

Donaldson和他的研究小組發現日光能和灰塵中存在的硝酸相互作用，把它們踢回大氣中，並在那裡形成霧霾。他們通過裝在盤子裡的玻璃球驗證了這個過 程，盤子裡的玻璃球模擬窗戶玻璃但表面積更大——玻璃球被放在了多倫多市中心的戶外，以及德國萊比錫的戶外。被放在陽光下的玻璃比陰暗處的玻璃多減少了 10%的含氮化合物。

「The total amount of nitrogen oxides entering a city is probably well captured in models. What is not well captured is the fact that the losses are less than people had considered because a loss from the gas phase to the grime surface does not constitute a permanent loss.」
進入城市的氮氧化物總量或許在模型中可以被很好的捕獲到。我們不能很好的捕捉到信息的是這些損失比人們想像的要少很多，因為從氣相到污染表面的元素損失並不屬於永久損失。

So grime is not as inert as we thought it was. And city beautification efforts, aimed at making buildings more pleasing to the eye, might also make the urban environment more pleasant for the lungs.
所以，塵垢並不是像我們認為的那樣惰性不活潑的物質。美化城市的工作，目的在於讓建築物更養眼 ，同時也可以讓城市環境更加養肺。