异丁烯两段催化氧化制甲基丙烯酸催化剂研究 Ⅰ．异丁烯气相氧化制甲基丙烯醛多元复合氧化物催化剂的研究

本文报导用于异丁烯（叔丁醇）选择氧化制ＭＡＬ（甲基丙烯醛）的多元复合氧化物催化剂的研究结果。同共沉淀法制备的催化剂的活性主要决定于其化学组成，同时受到制备条件的影响。最佳催化剂的主要物相组成为ＰｂＯ３，Ｂｉ２ＭｏＯ３．３、ＮｉＭｏＯ４、Ｓｂ２Ｏ３及ａ－Ｆｅ２Ｏ３小颗粒。在３５５℃，１０００～２５００ｈ－１空速范围，叔丁醇：水：空气＝１：３．３：７（摩尔比）的条件下可获得异丁烯转化率达９６％，ＭＡＬ选择性达８９％的结果。     

IR study of the interaction of hydroxyl groups of silica gel with Cr species of Phillips' type catalysts

Spectroscopic evidence for the interaction of hydroxyl groups and chromium ions was obtained using a catalyst prepared from chromyl chloride. A new OH peak, observed at 3705 cm^–1 after pumping away CO gas, is attributed to the direct interaction of OH with the low-valent chromium. This peak shifts to 3590 cm^–1 on contact with O₂ at room temperature and it is assigned to a hydroxyl interacting with the oxidized chromium. New assignments are also proposed for IR bands of CO presorbed on the catalyst. The peak due to CO at 2188 cm^–1 decreases as the OH intensity at 3705 cm^–1 increases, suggesting that the former peak arises from adsorption on Cr(II) species to which two oxygen atoms are attached.     

通过细乳液聚合方法制备自交联型有机硅乳液

苯乙烯与甲基丙烯酸-3-三甲氧基硅丙酯(M PS)经细乳液聚合,制得了稳定的自交联型的水分散涂料,用透射电子显微镜(TEM)、动态光散射仪(DLS)和红外光谱(IR)表征了乳胶粒的形态和结构。发现与传统乳液聚合相比,细乳液聚合法可显著提高乳液的稳定性,且M PS加入量的增加会导致乳液稳定性降低。     

SO_4~（2－）／ZrO_2固体超强酸的失活与再生

初步探索了ＳＯ_４~２－／ＺｒＯ２固体超强酸的失活机理．并着重研究了催化剂的两种再生方法：灼烧法和溶剂洗涤法。催化剂主要是因结焦而失活，高温灼烧能基本恢复催化剂原有活性．且再生效果与灼烧温度有关。溶剂洗涤法有一定的再生能力，但不显著．     

石蜡聚苯乙烯微球的制备

通过悬浮聚合技术合成了石蜡聚苯乙烯微球，研究了合成过程中引发剂浓度及交联剂用量对微球粒径及其分布的影响。     

新型层状表面相锆基固体酸催化酯化反应研究

将所研制的层状表面相锆基固体酸催化剂用于一元、二元醇醋酸酯和其他羧酸酯类产品的合成 ,考察了其催化性能。研究发现 :层状表面相锆基固体酸催化剂对所考察的酯化反应具有很好的普遍适用性 ,但其酯化率与醇的性质和结构密切有关。催化反应动力学研究表明乙酸与丁醇、戊醇、己醇的酯化反应均为二级反应 ,且反应活化能均较低 ,分别为 47 4kJ/mol、2 3 3kJ/mol和 19 8kJ/mo     

种子法制备聚合物乳液技术的进展

从建筑乳液的生产现状、自生种子法与外加种子法的区别、种子乳液的特点及外加种子法生产的乳液特性等方面介绍了种子法制备乳液技术的进展。     

Effect of Pt Incorporation into Ni/ZrO2–SO 4 = /Al2O3 Catalyst for n-Butane Isomerization

Three Ni/ZrO₂–SO₄⁼/Al₂O₃ catalysts with different concentrations of platinum (0.2, 0.3 and 0.4 wt%) were prepare and tested for n-butane isomerization reaction at 338 K, in absence and in presence of hydrogen. The results shown that, at low temperature, platinum contributes to the olefin or butyl ion formation and the reaction follows a bimolecular pathway. However, when the reaction occurs in the presence of hydrogen, the formation of butyl ions is inhibited. The main feature of platinum addition is the stabilization of the catalytic activity, which is indicated by the slow deactivation constants compared to that of the unpromoted catalyst.     

COMPUTER SIMULATION OF HYDRODEMETALLATION IN FIXED-BED REACTORS

An isothermal model for hydrodemetallation (HDM) of crude oils in catalytic fixed-bed reactors is proposed. This model involves a consecutive reaction mechanism, which is capable of accounting for particle deposit profiles with interior maxima. Consistent with the fact that HDM catalysts are conglomerates formed by precipitation, the porous catalyst itself is modeled as randomly overlapping spheres of equal size. The metal is deposited as growing metal sulfide crystallites on the inner surface of the catalyst. These crystallites originate from a certain number of randomly scattered nuclei and increase in size as the deposition proceeds. The random sphere model for the catalyst and the deposit provides the changes in the catalyst pore structure—local porosity and surface area.

The mass transport within the domain of the particle is due to restricted liquid diffusion, since the diameter of the metal bearing compound (porphyrin) and the intermediate are comparable to the pore size. The diffusion restrictions taken into account are the enhanced drag imposed on a molecule by adjacent pore walls and steric partitioning.

Since the deposition process is much slower than diffusion and reaction, the pseudo-steady-state assumption can be justified. The equations of conservation for mass are solved by orthogonal collocation on finite elements. Based on this solution technique a computer simulation program of HDM is designed that allows two modes of operation: constant temperature and constant conversion. The simulation program “SIMULA” is highly flexible with regard to reaction kinetics, catalyst structure, reactor design, and operating conditions. In comparison to a base case with uniform activity, the effect of intraparticle (radial) and bed (axial) activity profiles on the conversion rate is discussed. For the case investigated, a radial distribution of activity higher at the center of the particle than at the edge can increase catalyst life by 25%, but axial distribution was less successful.     

角蛋白基药物载体的发展及应用探讨

从毛发中提取角蛋白，开发具有独特功能的角蛋白基药物载体材料，提高药物的活性和生物利用率，既能够增加毛发的利用价值，又能够实现节能减排，符合可持续发展战略要求。对毛发中提取角蛋白进行二硫键重建、自由基聚合、多糖改性和烷基化等改性处理，赋予角蛋白基药物载体优异地功能特性，进一步拓宽其作为角蛋白基药物载体的应用范围。角蛋白基药物载体可被加工成纳米粒子、纤维支架、水凝胶等各种形式用于药物的递送。作为一种高硫含量且具有良好细胞相容性的结构蛋白，角蛋白基药物载体在组织工程、再生医学等领域扮演着重要的角色。