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From VOA Learning English, this is the Agriculture Report.
Students at the University of Virginia have developed a new way to purify water. They say it could bring improved water quality to millions of people in the developing world. They call it MadiDrop. Field testing began recently in South Africa. The laboratory where the MadiDrop is made operates like a kitchen. Workers add ingredients and mix, weigh, press and bake.
What the workers are making is a ceramic disc that contains silver. When the disc is dropped into water, silver ions are released to purify the water. Ions are atoms that have an electrical charge. Testing at the University of Virginia shows that the disc produces clean, safe water. Beeta Ehdaie studies at the University of Virginia. She says her work is not only about making effective technology. It is also about making solutions for people in developing countries who do not have many resources.
Why the name “MadiDrop”? The word “madi” means water in Tshivenda, a language of Limpopo province in South Africa. There, 50 women run a factory that makes water filters. The university started the factory last summer. The women mix sawdust and clay to make flowerpot-shaped filters that they use to purify drinking water. The water flows through the filters, which trap bacteria and solid particles. The factory sells the filters to local families. But the MadiDrop is smaller and less expensive than the filters. Over the next few months, students will test the MadiDrop in South Africa. If the testing is successful, the South African women will make and sell the MadiDrops. The goal is to expand to other developing countries, and improve millions of lives.
