乙烯齐聚催化剂研究进展

乙烯齐聚是合成直链低碳α-烯烃最先进的方法，直链低碳α-烯烃可用于生产低密度聚乙烯和高密度聚乙烯等多种精细化学品。本文综述了乙烯齐聚催化体系的研究进展，重点介绍了镍、锆、钛催化剂的组成以及反应时间、反应温度、溶剂、助催化剂等因素对乙烯齐聚活性和选择性的影响，并讨论了典型镍的催化机理。     

脱落酸、乙烯和赤霉素对豌豆苗采后品质的影响

为了解植物生长调节剂对幼苗类蔬菜采后品质变化的影响，用脱落酸、乙烯、赤霉素处理豌豆苗（Pisum Satu-vum L.）。结果表明：脱落酸和乙烯处理加速了叶绿素、蛋白质、可溶性糖含量的下降和纤维素含量的升高。而赤霉素处理则显著延缓了叶绿素、蛋白质和可溶性糖含量的下降和纤维素含量的增加。     

百万吨级乙烯冷箱的设计

分析了百万吨级乙烯冷箱的设计难点和采取的对策，介绍杭氧设计、制造的乙烯冷箱的技术参数和设计方案，与国外公司设计方案的比较，说明杭氧乙烯冷箱的设计、制造技术与世界先进水平的差距大大缩小。     

乙烯装置失效模式分析及基于风险的检验

简述了乙烯装置的工艺流程,分析了装置中常见的几种失效模式及其分布;以乙烯裂解装置为例,简述了RBI的执行过程和结果,从基于风险的检验理念,对制订设备检验策略提出了几点建议。     

Encapsulation of PV modules using ethylene vinyl acetate copolymer as a pottant: A critical review

The primary purpose of this work is to review the literature about what is and is not known about using ethylene vinyl acetate (EVA0 copolymer as the encapsulant (or pottant) material in photovoltaic (PV) modules. Secondary purposes include elucidating the complexity of the encapsulation problem, providing an overview about encapsulation of PV cells and modules, providing a historical overview of the relevant research and development on EVA, summarizing performance losses reported for PV systems deployed since ca. 1981, and summarizing the general problems of polymer stability in a solar environment. We also provide a critical review of aspects of reported work for cases that we believe are important.Failure modes resolved in the early work to establish reliability of deployed modules and the purposes and properties of pottants, are summarized. Typical performance losses in large field-deployed, large-scale systems ranging from 1% to 10% per year are given quantitatively, and qualitative reports of EVA discoloration are summarized with respect to ultraviolet (UV), world-wide location and site dependence.The general stability of polymers and their desirable bulk properties for solar utilization are given. The stabilization formulation for EVA, its effectiveness, and changes in it during degradation are discussed. The degradation mechanisms for the base resin, e.g., unstabilized Elvax 150^TM, and stabilized EVA are indicated for literature dating to the early 1950s, and the role played by unsaturated chromophores is indicated. The limited number of studies relating discoloration and PV cell efficiency are summarized.Observed degradation of EVA or the unstabilized base resin in the laboratory and examples used to measure the degradation are summarized in sections entitled: (1) thermally-induced degradation; (2) photodegradation and photothermal degradation of EVA in different temperature regimes; (3) photobleaching and photodegradation of the UV absorber and cross-linking agent; (4) acetic acid and metal and metal-oxide catalyzed oxidative degradation; and (5) discolaration and PV cell efficiency losses.Processing effects/influences on EVA stability are discussed in sections entitled: (1) EVA raw materials and extruded, uncured films; (2) thermal encapsulation processes; (3) effects of lamination, curing, and curing peroxide on gel content and chromophores formed; and (4) incomplete shielding of curing-generated chromophores. A summary is given for the limited number of accelerated lifetime testing efforts and examples of erroneous service lifetime predictions for EVA are discussed. The known factors that effect the discoloration rate of several EVA formulations are discussed in which the reduction in rate by using UV-absorbing superstrates is a prime example. A summary is given of what is and is not known about EVA degradation mechanisms, degradation from exposures in field-deployed modeules and/or laboratory testing, and factors that contribute to EVA stability or degradation. Finally, conclusions about using Elvax 150 in EVA formulations are summarized, and future prospects for developing the next-generation pottant for encapsulating PV modules are discussed.     

强化乙烯生产管理提升企业竞争能力

回顾了中国石油天然气股份公司所属乙烯装置2002年的生产情况，总结了乙烯生产管理中取得的经验和存在的问题，并提出了今后乙烯生产管理的目标。     

环氧乙烷合成乙二醇的研究进展

介绍了环氧乙烷合成乙二醇的主要生产方法，包括以壳牌、联碳化学公司以及Halcon—SD公司为代表的环氧乙烷直接水合法，环氧乙烷催化水合法和碳酸乙烯酯法，后两种乙二醇生产方法是目前国内外研究开发的热点。催化剂体系是催化水合法工艺的关键，重点介绍了国内外各主要公司对催化剂体系的研究进展及使用效果；碳酸乙烯酯法分为乙二醇和碳酸二甲酯联产法以及碳酸乙烯酯水解法，详细介绍了国内外各主要公司对该技术的研究进展，包括工艺流程、催化剂体系等方面。将3种乙二醇生产方法进行技术经济比较，结果表明，催化水合法和碳酸乙烯酯法在原料消耗和能耗方面占优势。并对我国乙二醇生产工艺技术提出建议。     

The effect of support morphology on the reaction of oxidative dehydrogenation of ethane to ethylene at short contact times

The oxidative dehydrogenation of ethane is carried out in short contact time reactors over Pt and LaMnO₃ based catalysts supported on a large number of different ceramic substrates (45, 60 and 80 ppi foam monoliths and 200, 400, 600, 900 and 1200 cpsi honeycomb monoliths). Experimental results, obtained under the same conditions at varying the C₂H₆/O₂ ratio, showed that the highest performance in terms of ethylene selectivity and yield is always attained on LaMnO₃ catalysts. Furthermore, the results are significantly influenced by the morphology and cell density of the support, with 45 and 60 ppi foams and 400 and 600 cpsi honeycombs giving the best performance. The experimental results are explained by means of geometrical and fluid dynamic considerations on the support, and by means of a 2D mathematical model, which clearly indicates an optimal intermediate cell density for maximising ethylene selectivity and yield.     

聚氧乙烯化大豆油脚硫酸钠的合成

以大豆油脚为原料,经聚氧乙烯化、硫酸化合成出一种新型的表面活性剂。     

DIRECT OXIDATION OF ETHYLENE TO ACETALDEHYDE IN A HOLLOW FIBER MEMBRANE REACTOR†

A hollow fiber membrane reactor, which resembles a tube-and-shell heat exchanger, was developed for homogeneous catalytic reactions with gas reactants and products. The gas stream flows through the tube side while the reaction takes place in the catalyst solution which fills the shell side. The separation load of product from the catalyst solution can be reduced by using a hollow fiber membrane reactor instead of a conventional bubble column reactor. The reactor operates in a plug-flow pattern with a large mass transfer area per unit volume of catalyst solution

This concept was investigated experimentally using the direct oxidation of ethylene to acetaldehyde reaction in an aqueous solution of palladium (H) chloride-cupric chloride with a silicone rubber membrane reactor and a polypropylene membrane reactor. It was experimentally demonstrated that membrane reactors could achieve higher production rates per unit volume of catalyst than the conventional sparged reactor. The experimental data were in good agreement with the predictions by the mathematical model. The conditions under which the membrane reactor will be more advantageous than the conventional sparged reactors can be readily ascertained with the analytical solution of the simplified membrane reactor model.