Dressing of filigree fine-grained metal bonded grinding wheels

Metal bonded grinding tools offer a remarkable potential for micro grinding because of their favorable wear behavior. However, metal bonded grinding tools, especially dicing blades, are hard to dress by conventional dressing methods. Electro contact discharge dressing, which is presented in this paper, is a numerically controlled dressing process offering the possibility to create the geometry and topography of the grinding wheel simultaneously at negligible dressing forces. The power of an electric circuit thermally removes the metal bond of the grinding wheel during the dressing process. The quality of the created profiles and the influence of the dressing parameters on the specific material removal rate of the grinding tool as well as the wear of the electrode are investigated at fine-grained grinding wheels.     

一种新型气动装袋装置研制

装袋是食用菌代替料生产过程中的一个重要环节。针对工作强度大、安全性低的现状,研发了一种新型气动工艺装袋机。实践结果表明:该设备能较好满足当前食用菌代料生产中装袋操作要求,且具有结构简单、生产率高、成本低、安全性好的特征。     

中国石化2004年乙烯生产述评

在对中国石化集团公司2004年乙烯生产运行情况进行简要回顾与分析的基础上,提出2005年工作重点及其具体措施。     

Technological parameters that influence the production of ozone in A .D. C. Corona discharfe

Experiments using dry oxygen in a wire–to–cylinder ozone generator, submitted to D.C. corona discharges show that technological parameters (diameter and composition of wire and cylinder, length of cell, gas flow and transit time of the gas) greatly influence ozone production. The cell geometry to be used depends on the polarity of the D.C. voltage applied to the wire and, for a predetermined design, the maximum ozone production rate will be obtained by seeking the most suitable gas flow. Lining up a series of optimized cells can give significant results.     

PVC防水卷材的配方研究

研究了利用废旧软聚氯乙烯回收料(旧料)生产PVC塑料防水卷材的配方及其对卷材拉伸性能的影响。结果表明,PVC塑料卷材的拉伸强度和断裂伸长率随PVC树脂添加比例增加而提高,而相同添加量的SG-3型PVC树脂比SG-5型PVC树脂的拉伸性能高；在试验范围内,增塑剂用量增加,卷材的拉伸强度降低,伸长率先升后降；添加CPE能提高PVC卷材伸长率,但拉伸强度有所下降。当CaCO_3用量低于20份时,卷材的拉伸强度和伸长率随CaCO_3添加量增加而提高。PVC防水卷材的优选配方(质量份)：旧料85份,PVC树脂(SG-3型)15份,DOP 5份,CPE 3份,稳定剂(TLS)0．6份,其它助剂适量。     

我国色母粒的生产现状与发展趋势

本文介绍了我国色母粒的生产现状、存在的问题及今后的发展趋势,并提出了一些建议。     

汽车刹车片用改性酚醛树脂的生产

在原有的酚醛树脂生产设备上，用腰果壳油和三聚氰胺对酚醛树脂进行改性，制得的改性树脂具有较好的软化点、聚合速度、挥发度和游离酚等性能；并且热分解温度较普通酚醛树脂大大提高。用它作胶粘剂生产的汽车刹车片，冲击强度增大：磨损率降低、摩擦性能提高、产品成本也大为降低。     

Feasibility of Sludge Ozonation for Stabilization and Conditioning

A pilot-scale sludge treatment plant was built to investigate the feasibility of ozonation processes for waste activated sludge treatment. Ozonation of wastewater sludge resulted in mass reduction by mineralization as well as by supernatant and filtrate recycle. Another advantage of sludge ozonation is a significant improvement of settleability and dewaterability. Experimental results showed that mass reduction of 70% and volume reduction of 85% compared with the control sludge was achieved through the sludge ozonation at a dose of 0.5?gO₃/gDS. It is also interesting to note that the filterability deteriorates up to ozone dose of 0.2?gO₃/gDS and then improves considerably at a higher ozone dose. The filterability could be improved by chemical conditioning even at a low ozone dose. The economic feasibility by cost analysis reveals that ozonation processes can be more economical than other alternative processes for sludge treatment and disposal at small-sized wastewater treatment plants.     

K系维生素中间体β-甲基萘醌合成的研究进展

综述了K系维生素中间体β—甲基萘醚(2—甲基—1，4—萘醚，维生素K；)的合成方法及其研究进展，并就当前工业生产技术中存在的问题，提出了适宜而合理的发展方向。     

改良FMC技术生产CS2工艺流程

介绍国内外CS2生产工艺发展情况，讨论了改良FMC技术生产CS2工艺及应用。