The water resistance of PVA was increased by using urea. The product was tested by the method of solvent extraction. The best modification condition was found.

用尿素对聚乙烯醇基料进行了改性，使其耐水性得到提高。并用溶剂萃取法对其耐水性进行了测试，确定了最佳改性条件。

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In general, application mainly includes four aspects: separation of microbe, removal of metabolism waste, extraction and concentration of product, treatment of high strength waste water.

一般而言，其应用主要包括四个方面：分离微生物、除去代谢废物、提取浓缩产品和处理高浓度废水。

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This product is a high molecular weight phenolic compounds vinegar, no color, no pollution, aging heat load, heat water extraction, less volatile, usually used as the primary antioxidant.

本品是一种高分子量酚类醋化物，不变色、不污染、耐热载老化、耐热水萃取、不易挥发，通常用作主抗氧化剂。

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