The use of 3,3′,4′,5‐tetrachlorosalicylanilide as a chemical uncoupler to reduce activated sludge yield

To determine whether chemical additions can be used to reduce sludge production in biological wastewater treatment, 3,3′,4′,5‐tetrachlorosalicylanilide (TCS) was added to activated sludge cultures as a metabolic uncoupler. Batch tests confirmed that TCS is an effective chemical uncoupler in reducing the sludge yield at concentrations greater than 1.0 mg dm^?3; a TCS concentration of 1.0 mg dm^?3 reduced sludge yield by approximately 50%. Substrate removal capability and effluent nitrogen concentration were not affected adversely by the presence of TCS when dosed every other day in a range of 2.0–3.6 mg dm^?3 during the 40‐day operation of activated sludge batch cultures. Such sludge growth reduction was associated with the enhancement of microbial activities in terms of the specific oxygen uptake rate and dehydrogenase activity. Sludge settleability of the treated and control samples was qualitatively comparable and not significantly different. Filamentous bacteria continued to grow in sludge flocs only in the control reactor at the end of the 40‐day trial. These results suggest that TCS treatment of activated sludge systems may reduce excess sludge yield. Copyright © 2003 Society of Chemical Industry     

微凝胶驱技术在下二门油田的应用

微凝胶驱可以解决聚合物用量高、耐温抗盐性能差的问题。用下二门油田污水配制的Cr3+/HPAM微凝胶体系(0.4g/LHPAM、0.06g/LCr3+)50℃老化180d,黏度保持在130mPa·s左右,可作为驱剂使用。单井注入试验和多井组矿场先导试验表明,该体系可注性良好,在地层中具有良好的成胶性能。微凝胶驱注入压力上升幅度、视吸水指数下降幅度以及改善吸水剖面的能力都比聚合物驱大,使后续流体转向聚合物驱波及不到的中低渗透率层,进一步扩大波及体积;在与聚合物驱(1g/LHPAM)同等驱油效果的情况下,微凝胶驱的化学剂(聚合物、交联剂)费用成本下降了21%,经济效益十分明显。图4表3参6     

Preparation of copolymer of L‐aspartic acid and L‐glutamic acid

In this article, a new copolymer of L ‐aspartic acid and L ‐glutamic acid, which may be a biodegradable high molecular polymer and can be used more widely in many areas, was synthesized. The conditions of preparation, such as catalyst, reaction time, reaction temperature, the amount of catalyst, the times of adding catalyst, and the molar ratio of L ‐aspartic acid to L ‐glutamic acid, were optimized. The copolymer was characterized by ¹³C NMR, infrared spectroscopy, and X‐ray diffractometer. The molecular weight was determined by GPC. The result indicated that production yield, purity of product, and molecular weight of product increased with amount of catalyst and molar ratio of L ‐aspartic acid to L ‐glutamic acid increasing. The best condition of preparation was the following: reacting 2–4 h at the temperature of 180–200°C. The product yield with the molecular weight 13,000.00 reached 63.2% and the purity of product was 96.33% when the copolymerization was carried out at the temperature of 200°C under vacuum for 2 h. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3626–3633, 2006     

MB－86催化剂在年产5万t丙烯腈装置上的应用

介绍了ＭＢ－８６催化剂在中国石化大庆石油化工总厂年产５万ｔ丙烯腈装置上首次工业应用的情况、工艺条件和使用效果。该装置在使用ＭＢ－８６催化剂后，在合适的工艺操作条件下，丙烯腈收率可达到８０％以上。     

Zincate mechanism on cast Al-Si alloy in non-cyanide multi-metal zincate solutions

1 Introduction Si is an important element in Al-Si alloys, the content of which greatly affects the physical, mechanical and chemical properties of Al-Si alloys[1?3]. Due to special structure and cast techniques[4, 5], pre-treatment of cast Al-Si alloys b…     

钢制压力容器残余应力的Mises屈服条件确定法

利用Mises屈服条件建立了确定钢制压力容器焊接残余应力的方法,即只要测点进入屈服状态,就完全可以确定该点两个主应力方向的残余应力。并指出该方法是一种确定钢制压力容器残余应力的简易方法。     

提高4A沸石产量的有效途径

4A沸石生产过程中，水热合成反应(溶铝、混胶、结晶)在夹套反应釜中进行。结晶的4A沸石沉积于釜底。因此结晶时间成为影响产量的限制因子。该文针对性地提出增加结晶池，在反应釜中完成水热合成反应之后，转入结晶池完成结晶工艺，提高反应釜的利用率，从而提高产量。     

Simulation Techniques for the Manufacturing Test of MCMs

Simulation techniques used in the Manufacturing Test SIMulator(MTSIM) are described. MTSIM is a Concurrent Engineering tool used tosimulate the manufacturing test andrepair aspects of boards and MCMs from design concept through manufacturing release. MTSIM helps designers select assemblyprocess, specify Design For Test (DFT) features, select board testcoverage, specify ASIC defect level goals, establish productfeasibility, and predict manufacturing quality and cost goals. A newyield model for boards and MCMs which accounts for theclustering of solder defects is introduced and used topredict the yield at each test step. In addition, MTSIMestimates the average number of defects per board detected at eachtest step, and estimates costs incurred in test execution, faultisolation and repair. MTSIM models were validated withhigh performance assemblies at Hewlett-Packard (HP).     

RHZ-300YL型裂化催化剂的研制及其在印度尼西亚的应用

针对印度尼西亚SUNGAI GERONG炼油厂重油催化裂化装置的特点及对产品的要求，开发了RHZ-300YL型催化剂。该剂采用了超稳Y型分子筛的改性技术及活性担体技术，并对催化剂配方进行了优化，使该剂具有重油裂化能力强、活性稳定性好、丙烯及汽油产率高等特点。该剂在印度尼西亚SUNGAI GERONG炼油厂催化裂化装置工业应用表明。在掺炼渣油的条件下，丙烯产率达到5．65％，汽油产率达到50．5％。     

改进钢锭断面形状提高厚板成材率的变形实验

简述了钢锭断面形状对厚板成材率的作用。着重阐述模拟舞阳钢铁公司４２００ｍｍ厚板轧机的轧制工艺条件，轧制８．０ｔ镇静钢扁锭，采用正交设计法确定钢锭断面最佳尺寸。得到了在确定轧制工艺条件下，正确确定最佳钢锭断面尺寸的正交回归数学模型。在本实验最佳断面形状的锭型与合适的工艺相匹配下，厚板成材率约提高５．２７６％，边部切损率约降低３．６３５％。