美国有线新闻 CNN 灌溉沙漠(2)(在线收听) |
Both groups hope to get around these complications, but in different ways. 两组人都希望避免这些问题,但使用的方式不同。 The researchers at Berkeley, led by Omar Yaghi, announced their results last year. Omar Yaghi领导的伯克利的研究人员在去年宣布了他们的结果。 They propose to replace the zirconium-based metal-organic framework with one based on aluminium. 他们建议将锆基金属有机骨架替换为铝基金属有机骨架。 Not only is aluminium cheaper than zirconium, it is better at binding to and then releasing water, making the trap's operation smoother. 铝不仅比锆便宜,而且更容易与水结合并释放水,使捕集器的操作更加顺畅。 On top of this, Dr Yaghi has found that by mixing graphite into the powder from which the framework is compounded, 最重要的是,Yaghi博士发现,通过将石墨与粉末混合制成框架, in order to make it black, and therefore heat-absorbing, he can eliminate the need for copper foam. 使其变黑,从而达到吸收热量的目的,他可以消除对泡沫铜的需求。 In Connecticut, meanwhile, Steven Suib and his colleagues, 与此同时,在康涅狄格州,Steven Suib和他的同事 who have just reported their result in Environmental Science and Technology Letters, propose getting rid of both framework and foam, 在《Environmental Science and Technology Letters》中发表了自己的结果,他们建议抛弃框架和泡沫, and replacing them with birnessite, a type of manganese dioxide. Birnessite is abundant in nature. 用将它们替换为水钠锰矿—一种二氧化锰。水钠锰矿资源丰富。 It is also easy to make artificially. It is therefore cheap. 人工制作也很容易。因此,它很便宜。 Like metal-organic frameworks, birnessite is riddled with tiny holes that allow air to move around inside it, to maximise adsorption. 和金属-有机骨架一样,水钠锰矿布满了小孔,空气可以在里面流动,最大限度地吸附。 And it, too, is black and therefore heat-absorbing. 它也是黑色的,因此可以吸收热量。 Both proposals work. Tested in desertlike conditions in a laboratory—and in Dr Yaghi's case in an actual desert, too— 两种建议都可行。在类似沙漠的条件下在实验室里测试—Yaghi博士是在真正的沙漠中进行测试的— they absorb and regurgitate reasonable fractions of their weight of water every day. They are nothing like as productive as desalination plants, 它们每天吸收和反刍相当比例的水。它们完全不像海水淡化厂那样高产, and so would have to be built at large scale to generate water in commercially useful quantities. 因此必须大规模建造才能产生商业上有用的水量。 But one thing deserts do have is lots of cheap land. If either or both of these inventions can be manufactured at scale, 但是沙漠里有很多便宜的土地。如果这两项发明中的一项或两项都能大规模生产出来, then the deserts may bloom—if not with plants, at least with water-collection farms. 那么沙漠就有可能蓬勃发展—如果不是用工厂,至少是用集水的农场。 |
原文地址:http://www.tingroom.com/lesson/cnn2020/1/495136.html |