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        ?

        Ask air for water

        2017-03-23 01:34:26
        農(nóng)村青少年科學探究 2017年12期

        Once Mayun said,“The cheapest thing in ten years will be houses and cars,while one of the most expensive things would be water—— clean water.”

        The earth we live on is called blue planet because over 70%of which is covered with water.It seems like there is a huge amount of water but most of which is salt water.Only fresh water is drinkable and not all of it can be attained easily.So the final number is less than 1%.You might say 1%is ok,but much of it was polluted.

        Over 160 countries depend on imported water.As it becomes increasingly scarce,it leads to conflicts and even war between countries.

        Take an example:the Nile starts in Ethiopia and ends in Egypt.That gives Ethiopia an upper hand in geopolitics,because if tensions prompted it,it could theoretically cut off or limit that huge water supply to Egypt.

        So how can we ensure that everyone get their fair share?

        One answer is to tap H2O from thin air.

        One team that has already been exploring water-harvesting technology is led by Omar Yaghi at the University of California,Berkeley.Using materials called metal organic frameworks– a powder that‘harvests’liquid from the atmosphere in its pores,they have shown that as little as 1kg of the powder can trap nearly 3 litres of water in only 12 hours.In humid parts of the world,this technology could provide an entirely new water source for people.

        馬云曾經(jīng)說過:“十年后,最便宜的是房子和車子,最昂貴的東西之一是水?!?/p>

        因為超過70%的表面被水覆蓋,地球被稱為“藍色星球”??此茡碛写罅康乃Y源,但大部分是鹽水。只有淡水可以飲用,但并不是所有的淡水都可以輕松獲得。最終數(shù)字是不超過1%。你可能會說1%也不少啊,但是(就是這1%)很多也已經(jīng)被污染。

        世界上有超過160個國家靠進口水生存。隨著水資源日益稀缺,會導致沖突和戰(zhàn)爭。

        舉例來說:尼羅河源頭在埃塞俄比亞,終點在埃及。在地緣政治上,埃塞俄比亞占了上風,因為如果兩個國家關(guān)系緊張,埃塞俄比亞可能會以斷水相威脅。

        那么,怎樣才能確保所有人都有水喝呢?

        跟空氣要水。

        一個由加利福尼亞大學(伯克利)Omar Yaghi領(lǐng)導的團隊已經(jīng)開始探索集水技術(shù)。使用名為“金屬有機框架”的材料——這種粉末材料可以通過自身的小孔吸收大氣中的液體。他們表示:僅僅1千克的粉末可以在短短的12小時內(nèi)捕獲近3公升的水。在世界上的潮濕的地區(qū),這種技術(shù)可以給人提供一個全新的水資源。

        Notes:

        Attain獲得;得到

        Explore探索

        Material材料

        Organic有機的

        Framework框架

        Pore毛孔;細孔。

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