Interfacial polycondensation of diphenolic acid and isophthaloyl chloride

Interfacial polycondensation of diphenolic acid (DPA) and isophthaloyl chloride (IPC) in various solvent/water systems was investigated with tetrabutyl ammonium chloride as a phase transfer catalyst. It was found that a large mass of capsules were formed at the beginning of the reaction for all solvents examined but the capsule morphology and reaction results depended on the solvents. It is believed that the capsule shells make up of the reaction zone and a mechanism of the interfacial polycondensation is proposed accordingly. The effect of the solvents on the reaction was interpreted from the interaction between the polymer and the solvent according to the mechanism. The reaction conditions were optimized, and poly(DPA-IPC) with high intrinsic viscosity was prepared in high yield under the optimal condition. It is an amorphous polymer with glass transition temperature of about 160°C. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

氧气顶吹转炉吹炼过程动态模型

通过炉气流量和成分的在线采样信息，用积分法计算熔池排出碳量，并根据熔炼体系中碳的守恒，动态推算熔池含碳量，由此来预报吹炼终点。较深入研究了提高炉气流量检测精度的方法，如心平衡修正和钢液成分反馈修正等，并采用了滤波算法，这些措施有利于提高动态模型的精度。     

聚酰亚胺的改性

本文介绍了旨在克服聚酰亚胺某些性能缺陷的改性产品 ,其中包括可溶型、透明型、低热膨胀型、共缩聚型、功能型、高粘接型、加成型聚酰亚胺和聚酰亚胺 /无机纳米复合材料等品种的研究动向 ,指出目前应重点研究聚酰亚胺 /无机纳米复合材料     

Nodally exact Ritz discretizations of 1D diffusion–absorption and Helmholtz equations by variational FIC and modified equation methods

This article presents the first application of the Finite Calculus (FIC) in a Ritz-FEM variational framework. FIC provides a steplength parametrization of mesh dimensions, which is used to modify the shape functions. This approach is applied to the FEM discretization of the steady-state, one-dimensional, diffusion–absorption and Helmholtz equations. Parametrized linear shape functions are directly inserted into a FIC functional. The resulting Ritz-FIC equations are symmetric and carry a element-level free parameter coming from the function modification process. Both constant- and variable-coefficient cases are studied. It is shown that the parameter can be used to produce nodally exact solutions for the constant coefficient case. The optimal value is found by matching the finite-order modified differential equation (FOMoDE) of the Ritz-FIC equations with the original field equation. The inclusion of the Ritz-FIC models in the context of templates is examined. This inclusion shows that there is an infinite number of nodally exact models for the constant coefficient case. The ingredients of these methods (FIC, Ritz, MoDE and templates) can be extended to multiple dimensions     

Study on Reduction of Sulfur Content in FCC Gasoline

Reduction of sulfur content in FCC gasoline was studied in a fixed fluid bed (FFB) unit by using metal-modified LV-23 FCC catalyst. The results showed that the sulfur content in FCC gasoline could be reduced with LV-23 catalyst modified with zinc, palladium, zinc-palladium, zinc-cobalt, and zinc-nickel. Among these metals or metal combinations, palladium-containing catalyst was the most effective. Desulfufization of the heavy fraction of FCC gasoline was more effective than full-range gasoline under the same conditions with palladium-containing catalysts. A high reaction temperature was favorable to desulfurization, but it would reduce the yield of liquid product. After desulfurization reaction, the olefm content of product gasoline decreased while the aromatic and iso-alkane contents increased. Removal of thiophene and benzothiophene is higher.     

吸水膨胀型膨润土/交联聚丙烯酰胺颗粒堵剂

使丙烯酰胺、少量N，N-亚甲基双丙烯酰胺在钙膨润土存在下进行水溶液引发接枝共聚合，聚合产物经造粒、粉碎、筛分，得到粒径0．5～1．0mm的颗粒堵剂。根据颗粒堵剂吸水量大小确定丙烯酰胺与膨润土最佳质量比为7：1，引发剂最佳用量为500g／t，交联剂最佳用量为300g／t，吸水量与这3个参数之间的关系曲线都经过最大值，颗粒堵剂在去离子水中的吸水量为560～650mL/g。该堵剂已大规模生产，在胜利、中原油田许多采油厂已用于调剖、堵水和调驱施工，在青海、江苏、大港、冀东等油田也已开始使用。在胜利东辛采油厂的一个井组，连续3个月在3口井注入该堵剂共27t，使井口压力上升3MPa，产油量大幅度增加。表l参l。     

超滤膜的改性研究及应用

随着超滤膜技术的发展，人们对超滤膜提出了各种各样的特性要求，其中解决膜表面的污染问题变得越来越紧迫．超滤膜改性，尤其是在膜表面引入亲水性基团是解决问题的关键．本文从这点出发，结合自身的工作，总结了近年高分子超滤膜改性方面的研究进展，包括表面活性剂在膜表面的吸附改性、等离子体改性、辐照改性、高分子合金和表面化学反应等几种改性方法．     

Prediction of the effects on dynamic response due to distributed structural modification with additional degrees of freedom

The aim of this study is to investigate means of efficiently assessing the effects of distributed structural modification on the dynamic properties of a complex structure. The dynamic properties of the modified structure can be determined by experimental testing or numerical simulation, both of which are complex, expensive and time-consuming. Assuming that the original dynamic characteristics are already established and that the modification is a relatively simple attachment, the modified dynamic properties may be determined numerically without solving the equations of motion of the full-modified structure. The frequency response functions (FRFs) of the modified structure can be computed by coupling the original FRFs and a delta dynamic stiffness matrix for the modification introduced. The validity of this approach is investigated by applying it to a cantilever beam to which a smaller beam is attached as modification. The original FRFs were obtained experimentally as well as numerically. The delta dynamic stiffness matrix was determined numerically by modeling the attachment and part of the original structure including the attachment points. The FRFs of the modified beam were then computed. Good agreement is obtained by comparing the results to the FRFs of the modified beam determined experimentally as well as by numerical modeling of the complete modified structure.     

Synthesis of poly(4-methylstyrene)- graft-poly(ethylene oxide)s and application as polymeric dispersant in coal-water mixture

Poly(4-methylstyrene)-graft-poly(ethylene oxide)s were prepared via polymerisation of ethylene oxide on to poly(4-methylstyrene)s functionalised with hydroxyl groups. In this way, many ‘comb-like’ polymers having different hydrophobic backbone length, hydrophilic branch length and frequency of branches were synthesised. These polymers were tested as dispersants in coal-water mixtures in order to correlate the dispersing properties of this class of polymers with the investigated parameters.