Preparation of microporous chlorinated poly(vinyl chloride) membrane in fabric and the characterization of their pore sizes and pore‐size distributions

Chlorinated poly(vinyl chloride) (CPVC)/poly(vinyl pyrrolidone) (PVP) membranes were prepared by using the solvent system tetrahydrofuran (THF)/n‐butyl alcohol (n‐BA) to investigate the possibility of pore size and pore‐size distribution control. The coagulation of CPVC/PVP solution was induced by the exposure to water vapor at 25 (±0.5)°C. The average pore diameter, d_p, and the size distribution of pores on the surface of the membrane were quantified through the image analyzer from the images visualized by field emission scanning electron microscope (FE‐SEM). Surface pore size and distribution of the prepared CPVC/PVP membrane were strongly affected by the relative humidity (RH) in the environment and the content of PVP used as an additive. Particularly, in the case of CPVC membrane without PVP, the mean pore size was 0.15–0.2 μm, depending on the RH. The pore distribution became broad with the increase of the RH. The membranes had open pores as confirmed by the hydraulic permeation experiment. In addition, the water flux and membrane resistance (R_m) were greatly affected by the composition of polymer solution and the RH. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1195–1202, 2002     

电石渣浆的综合治理与利用

介绍了综合治理电石乙炔法生产 PV C 时产生电石渣浆的工艺技术。采用电石渣浆废水全部 闭路循环回用工 艺,实现电石 渣浆上清液 的回收利用;同时以电石渣 代替熟石灰用 于环氧丙烷的生产。取得了显著的经济效益和社会环境效益。     

Complete Oxidation of Methane at Low Temperature over Pt Catalysts Supported on High Surface Area SnO2

The catalytic activity of Pt catalysts supported on high surface area tin(IV) oxide in the complete oxidation of CH₄ traces under lean conditions at low temperature was studied in the absence and in the presence of water (10 vol.%) or H₂S (100 vol.ppm). Their catalytic properties were compared to those of Pd/Al₂O₃ and Pt/Al₂O₃. In the absence of H₂S in the feed, Pt/SnO₂appears as a very promising catalyst for CH₄ oxidation, being even significantly more active under wet conditions than the best reference catalyst, Pd/Al₂O₃. Catalysts steamed-aged at 873 K were also studied in order to simulate long term ageing in real lean-burn NGV exhaust conditions. To this respect, Pt/SnO₂ is slightly less resistant than Pd/Al₂O₃. In the presence of H₂S, Pt/SnO₂catalysts are rapidly and almost completely poisoned, comparably to Pd/Al₂O₃and the catalytic activity is hardly restored upon oxidising treatment below 773 K. A synergetic effect between Pt and specific surface SnO₂sites active in CH₄oxidation is proposed to explain the superior catalytic behaviour of Pt/SnO₂.     

垂直管中油,气,水三相流总流量测量模型研究

基于集流型涡轮流量计与放射性低能源密度—持水率计在大庆生产测井研究所油、气、水三相流动环路中的实验响应结果，首先考察了用于气液两相流中涡轮流量计的Ａｙａ物理模型，进而提出了经过校正后用于确定油、气、水三相流总流量的测量模型，用此模型预测三相流总流量与流动环标定数据对比后其误差小于５％，满足了石油工业应用要求     

Highly Efficient Overall Water Splitting Through Optimization of Preparation and Operation Conditions of Layered Perovskite Photocatalysts

The layered perovskite materials were found to give the high photocatalytic activity in water splitting reaction under UV irradiation, where the electronic structure of perovskite slab constructing the layered structure (the total cation valency) was the most crucial factor to the high photocatalytic activity. Both the excessive cation valency and the layered structure were required for active photocatalysts, while the slab thickness of layered perovskites had an insignificant effect on water-splitting activity. In order to identify key variables that affected photocatalytic activity and to optimize the performance of (110) layered perovskite, La₂Ti₂O₇ was modified by various methods. The optimum amount of loaded nickel had a great effect and the amount depended on the surface area of the perovskite phase. When an alkaline-earth element such as Ba, Sr, and Ca was doped on La₂Ti₂O₇, the photocatalytic activity was enhanced markedly. Introduction of an alkaline hydroxide into the reaction system as an external additive enhanced the activity further showing extremely high quantum yields close to 50%.     

集成污水水质在线监测装置的研制

介绍基于流动注射分析法的集成污水水质监测仪的研制，该装置可自动检测水中的COD、NH3-N和pH值。     

火焰喷涂塑料粉末

介绍了塑料粉末火焰喷涂的原理、装置及工艺,聚乙烯、EVA树脂、尼龙、聚苯硫醚、氯化聚醚等涂层材料,以及这些涂层材料的耐腐蚀性能。     

甲醇装置高效分醇技术及双"零"节能工艺

针对甲醇分离系统存在的普遍性问题 ,提出了“少醇无水”工艺技术并进行了工业实际应用。在“少醇无水”工艺的基础上 ,又提出双“零”工艺的构思。分别对该两种工艺进行了经济效益分析。结果表明 :“少醇无水”工艺可使入塔醇含量由0 .987%降至 0 .5 62 % ,装置能力提高 6.0 %～ 11.12 % ;双“零”工艺可使 10万t/a甲醇装置生产能力提高 2 2 .0 0 %。     

用于确定双吸离心泵Suter曲线的三维内特性法研究

水泵Suter曲线是泵站水锤分析的必备条件之一。现有用于获取双吸离心泵Suter曲线的实测法具有难度大、成本高的特点,而间接插值估算法的精度又比较低,本文提出了一种通过水泵流场三维数值计算确定双吸离心泵Suter曲线的新方法,简称三维内特性法。该方法采用计算流体力学(CFD)技术,对双吸离心泵的水力模型进行三维造型、工况离散、流场计算及结果转化,以快速、准确地获取双吸离心泵Suter曲线,在正水泵工况、正水轮机工况、反水轮机工况、反水泵工况等工况下,计算出相应流量、转速、扬程和转矩关系。定量分析表明,相比于间接插值估算法,采用三维内特性法获得的Suter曲线中,Wh(x)的计算精度平均提高了39.2%,Wb(x)的计算精度平均提高了26.3%;在将采用该方法获得的双吸离心泵Suter曲线用于事故停泵工况水锤分析时,计算得到的系统最大压力降低了15.0%,管线发生汽化压力的范围缩减了81.4%,双吸离心泵的最大倒流量增大了11.9%,最大倒转速降低了6.1%,与实际测试结果更为接近。该方法为提高双吸离心泵站水锤分析精度提供了一种新技术途径。     

海上溢油漂移扩散的数值模拟

该文基于三维自由水面垂向分层动网格的Euler-Lagrangian模式,采用VC方式(Vertex-Centered)的非结构化有限体积方法离散三维浅水方程,模拟渤海的潮汐水流运动过程。以此为水动力背景场,采用油、水分离的Lagrangian粒子追踪模型,对渤海海域发生的溢油漂移扩散问题进行模拟。其油品的蒸发、乳化和溶解等风化作用以引入综合衰减系数的方式考虑。模型对油膜的漂移路径、厚度和面积进行了实时模拟和预测,用多个测站的同步连续实测值对水动力模式进行了参数率定与模型验证,油膜输运扩散的计算结果也与相关报告数据进行了对比,均吻合良好,说明模型具有较高的可靠性与重现性。