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Shining a Light on Water to Prevent Infections

andyg 于2007-11-11发布 l 已有人浏览
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&raquo Download Audio(mp3) By Jill Moss 2007-11-11 This is the VOA Special English Development Report.

» download audio(mp3)
by jill moss
2007-11-11

this is the voa special english development report.

viruses, bacteria and other organisms in dirty water sicken hundreds of millions of people every year. yet there are many different water-treatment technologies available.

the aquastar, made by meridian design

some systems use ultraviolet light to destroy harmful organisms. one product that disinfects water with uv light is called aquastar, made by meridian design.

the american company says most uv water-purification systems put into homes have one or more filters. these use carbon or mesh to catch impurities. the filters are added to improve the taste and smell of water.

but the company says a complex system like this is often not needed in situations where the aim is just to make water safe to drink.

the aquastar device is a one-liter bottle with an ultraviolet lamp inside. the user pushes a button and the light goes on for about a minute and a half. the lamp is powered by two small batteries.

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