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针对印染废水经二级处理后CODcr和色度不达标的难题,本文采用"以废治废"的方法,即采用制药厂的废弃AC,简单再生后深度处理经过二级生物处理的印染废水.研究结果表明,再生后的废AC进一步去除CODcr和色度的效果显著. 相似文献
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Microstructures and properties of SnZn-xEr lead-free solders 总被引:1,自引:0,他引:1
The Sn9Zn eutectic alloy is the nontoxic lead-free solders alternative having a melting temperature which is closest to that of the eutectic SnPb alloy. In order to improve the properties of SnZn lead-free solders, 0-0.5 wt.% of rare earth Er was added to the base alloys, and the microstructures were studied. Results showed that the addition of rare earth Er could enhance the wettability of SnZn solders, with 0.08%Er addition, the spreading area gave an 19.1% increase. And based on the mechanical testing, it was found that the tensile force and shear force of SnZn-xEr solder joints could be improved significantly. Moreover, the oxidation resistance of SnZn0.08Er solder was better than that of SnZn solder. In addition, it was found that trace amounts of rare earth Er could refine the microstructures of SnZn solders, especially for Zn-rich phases, and excessive amount of rare earth Er led to a coarse microstructure. 相似文献