焦化苯中的噻吩与乙醇在HZSM5沸石上的反应

焦化苯中加入少量的乙醇，在一定的温度下用ＨＺＳＭ５催化剂能将其中的噻吩分解生成硫化氢及微量的重组分硫化物．研究结果表明，反应体系中乙基正碳离子的存在是加速噻吩分解的主要原因，且当反应温度高于４００℃时，ＨＺＳＭ５催化剂脱噻吩活性的稳定性较好；在ｎ（Ｂ）／ｎ（ＥｔＯＨ）＝６５６（Ｂ为焦化苯），温度４００℃，常压，ＷＨＳＶ３５～３９ｈ－１的条件下，焦化苯中噻吩的脱除率可达９８％．     

沸石分子筛表面烷基锡接枝反应的研究

介绍表面金属有机化学方法改性沸石分子筛的研究概况，简要总结了近年来国内外对某些重要的分子筛（如，Y型沸石，镓磷沸石，丝光沸石，MCM－41）表面接枝烷基锡的研究成果，参考文献32篇。     

Poly(ethylene oxide) blends with crosslinking polyester resin

The miscibility of polyethylene oxide (PEO) with oligoester and polyester resin, the morphology of the blends and the kinetics of PEO crystallization in the blends were studied by optical microscopy and differential scanning calorimetry. The blends were found to be miscible with uncured resin at 60°C. After isothermal crystallization of PEO from liquid oligoester or UV cured polyester about 20% of the PEO material is still dissolved in the resin and it is incorporated between lamellae or in the interspherulitic regions. It was observed that the growth rate of PEO spherulites and the degree of crystallinity of PEO in the blends decreases very fast together with a decrease of the PEO content and the progress of the resin crosslinking.     

Production of multi-hollow polymer particles by the stepwise acid/alkali method

 Recently, we reported that multi-hollow polymer particles can be prepared from carboxylated polymer particles by the stepwise alkali/acid method. In this article, an attempt was made to prepare similar particles from acid-swellable polymer particles by the stepwise treatment with acid and alkali, which was named the stepwise acid/alkali method. The acid-swellable particles were produced by emulsion terpolymerization of styrene, butyl acrylate, and dimethyl 2-amino ethyl methacrylate. The effects of initial pH value, temperature, and time in the acid and alkali treatment processes on the multi-hollow structure were examined. Received: 18 December 1996 Accepted: 11 March 1997     

Role of solvent in the compatibility of a vinylchloride–vinylacetate–maleic acid terpolymer and nitrocellulose blends

The compatibility of cast films of a vinylchloride–vinylacetate–maleic acid terpolymer (VMCH) and nitrocellulose (NC) blends is influenced by solvents. Transparent films of VMCH/NC blends are obtained when cast from solvents such as tetrahydrofuran or cyclohexanone, whereas hazy films are obtained when cast from solvents such as acetone or ethylacetate. Visible spectroscopy and phase morphology were used to analyse the compatibility–incompatibility of the blend. Differential scanning calorimetry (DSC) studies demonstrate that the transparent film is compatible, but the hazy film is incompatible. Fourier transform infra-red (FTIR) studies establish that a greater interaction is observed between the polymer pair in case of the compatible blend than in the case of the incompatible blend. A solvent dependency of blend compatibility is reflected in this study. The conformational state of the polymers in solution, which is responsible for the compatibility phenomena, may depend on the donor number and/or Taft-β value of the solvent. The greater the donor number and/or the Taft-β value, the higher may be the level of interaction between the solvent and the polymer molecules, which in turn may give a compatible blend after removal of the solvent.     

New breathable and waterproof coatings for textiles: effect of an aliphatic polyurethane on the formation of PEEK-WC porous membranes

PEEK-WC is an amorphous polyetheretherketone with high chemical stability, excellent thermal resistance and significant solubility in various solvents. It has been used to prepare flat membranes by the phase inversion technique. The water vapour permeability through a porous PEEK-WC film was 1350 g/m² day at 26 °C and its liquid entry pressure (LEP) of water equivalent to a column of 2.0 m. These values were remarkably improved by addition of an aliphatic ether polyurethane (PU) into the PEEK-WC/DMF dopes: the water vapour flux was increased up to 2000 g/m² day and the LEP was equivalent to 12.5 m. This improvement is correlated to the different structure of the membranes: a spongy, porous and almost symmetric structure for the PEEK-WC/PU membranes, and an asymmetric structure with fingers for PEEK-WC membrane. The presence of PU influences also the mechanical properties of the blend membranes. The role of the PU on the resulting membrane morphology is rationalised on the basis of the mechanism of phase separation.     

Production of oxygen enriched air by rapid pressure swing adsorption

A novel rapid pressure swing adsorption (RPSA) process is described for production of 25–50% oxygen enriched air. The embodiment consists of one or more pairs of adsorbent layers contained in a single adsorption vessel. The layers undergo simultaneous pressurization-adsorption and simultaneous depressurization-purge steps. A total cycle time of 6–20 seconds is used. The process yields a very large specific oxygen production rate and a reasonable oxygen recovery for production of 20–50 mole% oxygen enriched gas.It is demonstrated by a simple mathematical model of isothermal single adsorbate pressure swing ad(de)sorption concept on a single adsorbent particle that the specific production rate of a PSA process cannot be indefinitely increased by reducing the cycle time of operation when adsorbate mass transfer resistances are finite.     

Heterogeneous Catalytic Partial Oxidation of C3-C4 Alkanes with Nitrogen Monoxide

The possibility of making products of partial oxidation, alcohols and acids in particular, by the reaction of C₃-C₄ alkanes with nitrogen monoxide over oxide and zeolite catalysts is demonstrated. The most effective catalysts are CeO₂ and Fe-TsVK. The dependence of the rate and selectivity of the process on the reaction conditions has been established.     

Ship-in-bottle formation of Ru_3(CO)_(12) in NaY zeolite

NaY zeolite entrapped Ru3(CO)12 cluster has been synthesized from RuCl3 ion-exchanged NaY, which is well characterized by IR and Raman spectroscopies and CO chemisorp-tion. When the Ru3+/NaY sample is heated from 298 K to 393 K for 25 h and for 10 h at 393 K, the sample colour changes from dark to brown-yellow. The in situ infrared spectrum exhibits absorption bands at 2130, 2064, 2040, 2017, 1990, 1953 and 1925 cm-1. The bands at 2130 cm-1 arises from the Runm+(CO)l m =1-3;n = 1 - 3; l = 1-12). The bands at 2064, 2040, 2017 and 1990 cm-1 are proposed to be associated with the Ru3(CO)12/NaY, which are close to Ru3(CO)12 crystalline. Furthermore, the Raman results provide bands at 150 and 185 cm-1, which can be attributed to Ru-Ru bonds of the sample as in the case of Ru3(CO)12 crystalline, for which the A1' Ru-Ru stretching mode is assigned to 185 cm-1 and E1' Ru-Ru stretching mode is assigned to a band at 150 cm-1, respectively. CO chemisorption of [Ru3]/NaY gives a CO/Ru ratio of 3.85, which is simila     

溶液的pH值对纳米CeO2晶粒形貌及形成机制的影响

以亚硝酸铈盐和氨水沉淀法合成了二氧化铈纳米粒子. 通过对溶液pH值的调节制备出了形貌各异的纳米CeO2晶粒. TEM和BET结果表明 酸性条件下, 得到的是球形的纳米CeO2晶粒且其比表面为148.1944 m2·g-1;中性时, CeO2晶粒的形貌为球形和棒状的混合形, 比表面为114.7975 m2·g-1;而碱性环境下, 易得到棒状的、比表面为106.2465 m2·g-1 的CeO2晶体. 另外还对各种形貌产物的形成机制进行了研究.