将以下文字翻译成英文。利用PEI中丰富的氨基基团通过界面聚合制备纳滤膜或者协同利用EPTAC中的季胺基团表面接枝对商业纳滤膜进行表面正电改性均能有效提高NF膜对一二阳离子体系的分离性能同时表现出更加优异的耐污染性能。荷正电纳滤膜这些特点预示其可广泛应用于重金属废水处理、水软化和资源回收等领域中。

By utilizing the rich amino groups in PEI for interfacial polymerization to prepare nanofiltration membranes, or by synergistically using the quaternary amine groups in EPTAC for surface cationic modification of commercial nanofiltration membranes, the NF membranes' separation performance towards mono- and divalent cation systems can be effectively improved, while showing more excellent pollution resistance. These characteristics of positively charged nanofiltration membranes indicate their wide application in fields such as heavy metal wastewater treatment, water softening, and resource recovery.