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厌氧--活性污泥法处理高浓度绢纺废水 总被引:4,自引:0,他引:4
介绍了厌氧—活性污泥法用复叶推流式曝气对高浓度绢纺废水治理的工程实例 ,运行结果表明 :CODcr去除率达 96.2 % ,BOD5 去除率达 92 .7%。 相似文献
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介绍了LD30大直径无缝薄壁筒采用热拉伸坯经变薄旋压成形工艺 ,讨论了其工艺过程 ,工艺参数和应用范围等。 相似文献
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结合缩径成形和旋压过程 ,建立了薄壁管缩径旋压变形力的理论计算模型和旋压力的计算公式 ,并对旋压方式、道次压下量Δ及旋轮进给比 f等成形工艺参数对滚珠旋压成形的影响进行了试验研究 相似文献
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Physical Properties and Fiber Morphology of Poly(lactic acid) Obtained from Continuous Two-Step Melt Spinning 总被引:1,自引:0,他引:1
Fibers of poly(lactic acid) (PLA) produced by two-step melt-spinning are studied. The PLA resin used contains a 98:02 ratio of l:d stereochemical centers. A range of processing conditions is explored. The cold-draw ratio is varied from 1 to 8 under conditions of constant heating. In addition, three draw ratios are studied at three different heating rates. The thermal, mechanical, and morphological properties of the resultant fibers are determined. Properties can be widely manipulated through a combination of draw ratio and draw temperature. A maximum tensile strength and modulus of 0.38 GPa and 3.2 GPa, respectively, are obtainable. Using atomic force microscopy, the fiber morphology is found to be highly fibrillar; microfibril diameters are roughly 40 nm in diameter. Very high draw ratios cause the fiber to turn from shiny and translucent to dull and white; this transition is attributed to surface crazing. Significant molecular weight loss is observed upon processing (weight-average molecular weights drops between 27% and 43%). 相似文献