字神帝國英語天地

今日主題：Sack Sulfates to Preserve Sewers
「解僱」硫酸鹽來保護下水道

洪欣老師推薦：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 (每句都要聽寫數遍，直到寫出85%以上的字)
3. 最後check文稿，看哪聽不出來，單字沒背過，還是發音不熟。
4. 堅持天天聽，就能每天進步哦。

MP3音檔 (按右鍵可下載聽)：喜歡的同學，幫忙推或按讚哦~~
http://online1.tingclass.net/voaspe/…/20140831sa_science.mp3

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：
Sewers are a marvel. They allow us to live close together without cities turning into smelly, disease-spreading swamps.
下水道堪稱奇蹟，它使我們緊密生活在一起時，並沒有使城市變得臭氣熏天，疾病氾濫成災。

In a sewer's anaerobic conditions, common sulfate compounds are reduced by bacteria to hydrogen sulfide—the source of that rotten egg smell. And hydrogen sulfide when exposed to air forms sulfuric acid. Which eats away at concrete. The result: crumbling sewers.
在下水道缺氧的情況下，常見的硫酸化合物可以被細菌轉化成硫化氫——這就是臭雞蛋氣味的來源。而暴露在空氣中時，硫化氫又會形成硫酸，硫酸可以侵蝕混凝土，結果就是會導致下水道破碎崩裂。

The response has been to try to remove sulfide from sewage water. But researchers in Australia asked a different question: where does the original sulfate come from? You can find more 60-Second Science on chinavoa.com.
過去人們對此的反應一直就是將硫化物從污水中分離出來，然而，澳大利亞的研究人員卻轉變了問題思路: 最初的硫化物來自哪裡呢?

Turns out much of it is from drinking water treatment. Aluminum sulfate is added at most Australian drinking water plants tested to coagulate solids out of the dirty water. That process is the source of more than half the resulting sulfates in the sewage. Numbers are similar in the U.S.
研究結果顯示，原來大部分硫化物是飲用水處理時產生的。在澳大利亞的飲用水水廠的污水中加入硫酸鋁進行檢測，結果顯示大多數飲用水水廠的污水裡出現了凝結顆粒。一半以上的下水道中硫化物的來自這一處理過程。該研究數據與美國數據相似。

The scientists say that by switching to nonsulfate-based coagulants, governments worldwide could save a billion dollars a year in sewer repair costs. The research is in the journal Science. [Ilje Pikaar et al, Reducing sewer corrosion through integrated urban water management]
科學家們稱，如果利用不含硫酸鹽的凝結劑來代替含有硫酸鹽的凝結劑，那麼世界各國政府每年就能在下水道的維修費用中省下10億美元，該項研究被發表在《科學》雜誌上。

Today, drinking water is managed separately from sewage treatment. A related editorial [Wolfgang Rauch and Manfred Kleidorfer, Replace contamination, not the pipes] calls for a holistic approach to water management that looks at the entire water cycle, and helps save sewers in the process.
—Cynthia Graber
現如今，飲用水的管理和廢水處理是分開進行的。一篇相關的社論呼籲稱: 要著眼於整個水循環系統，用全面的方法來管理水資源，而且在此過程中還要幫助挽救下水道。——辛西婭‧格雷伯