Technologies to solve the problems of providing fresh water and clean energy depend on filtering charged molecules called ions. One US company has developed a membrane technology which uses environmentally-friendly silica gel, a less-expensive, more durable alternative to polymers.

中文翻译：

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硅胶可提供柔性膜

解决提供淡水和清洁能源问题的技术取决于过滤带电分子，称为离子。一家美国公司开发了一种膜技术，该技术使用了环保的硅胶，这是一种成本更低，更耐用的聚合物替代品。