金属胶束催化体系中经Turing分支形成的空间有序结构与催化活性

摘要基于金属胶束催化反应的三元复合物动力学模型, 分析了金属胶束作为一类特殊的超分子体系, 其参与催化反应的特殊动力学行为与体系中可能出现的自组织结构的关系. 研究结果表明, 在一定的边界条件下, 即使基元反应是线性化学反应步骤, 由于扩散步骤与化学反应的耦合, 以及非理想性的组分热力学行为, 也将不可避免地出现经Turing分支形成的浓度场空间自组织. 计算结果表明, 这种宏观有序结构的形成将使金属胶束催化体系中呈现出以存在反应活性极高的位点为特征的反应活性的空间有序分布; 从自组织理论的角度对这类胶束体系催化活性的时空有序特征给予一定程度的阐释.     

纳米LiH的热稳定性与催化加氢反应活性

考察了纳米LiH在不同温度热处理后比表面积的变化及其与Cp2TiCl2组成催化剂的加氢反应活性之间的关系,300度热处理后LiH比表面积已呈较大幅度的下降,但催化剂的加氢反应活性反而更高,说明比表面积是克杨纳米LiH高活性的一个主要原因,但不是唯一 的因素。     

四苯基钴卟啉化合物催化过亚硝酸根分解的研究

利用紫外-可见分光光度计在乙醇介质中研究了合成的4种对位取代四苯基钴卟啉对过亚硝酸根分解的催化作用. 首次发现钴卟啉可以催化ONOO^－分解, 且对位带吸电子基团的钴卟啉比对位带供电子基团的钴卟啉催化活性高. TPPCoCl, T(p-CH₃)PPCoCl, T(p-OCH₃)PPCoCl和T(p-Cl)PPCoCl在乙醇中的k_cat分别为1.69×10², 1.52×10², 1.43×10²和1.20×10³ mol^－1•L•s^－1. 动力学曲线和时间分辨谱证明这些钴卟啉是通过形成中间体催化过亚硝酸根分解的.     

电解煤浆制氢阳极的制备及电催化活性研究

将钛片进行预处理, 用处理后的钛片作为电极基体, 然后用循环伏安法在钛基体上沉积制备了Pt/Ti, Pt-Ru/Ti, Pt-Ir/Ti, Pt-Ru-Ir/Ti催化电极, 通过扫描电镜(SEM)、X射线衍射(XRD)、电子能谱(EDS)以及等离子发射光谱(ICP)等方法对所制备电极进行了表征, 包括电极表面形貌、组分的沉积状态、催化层成分组成以及电极寿命等; 在煤浆电解过程中, 采用两电极体系, 对所制备电极的电催化活性进行了测试. 结果表明: 所制备的电极催化活性都高于同面积的铂片电极, 含有Ru, Ir的二元催化电极的活性好于镀铂催化电极. 在一定范围内, 随着Ru元素比例增大, 电极活性增强, 而Ir元素含量过大, 电极活性反而稍微降低, 所以Pt-Ir(1∶0.5)/Ti, Pt-Ru(1∶5)/Ti两电极的催化活性相对较好. 本文所制备的三元催化电极的催化活性低于二元催化电极. Pt-Ru/Ti电极催化活性最好, 相同条件下具有最大的电解电流, H₂的电解效率可达95%以上.     

CuO超细粉体的形貌与红外特性研究

CuO作为一种多功能精细无机材料，在印染、陶瓷、玻璃及医药等领域的应用已有数十年的历史，作为催化剂的主要活性成分，近年来在氧化、加氢、C１化学合成、NOx还原、CO及碳氢化合物燃烧、精细化工等多种催化反应中也得到了广泛的应用。可以推测，当CuO材料的粒度达到纳米级时，将使它的功能更加独特，应用更为广泛。因此CuO纳米材料的制备方法、聚集状态、与其他组分或载体的作用状况及催化活性等成为当前功能材料发展的研究热点之一犤１～８犦。我们在前文中报道了直接热解Cu２（OH）２CO３所得CuO粒径小、分布均匀、比表面积大，…     

Preparation of Ni/TiO2 Nanoparticles and Their Catalytic Performance on the Thermal Decomposition of Ammonium Perchlorate

Metal/oxide nanoparticles are attractive because of their special structure and better properties. The Ni/TiO₂ nanoparticles were prepared by a liquid phase chemical reduction method in this paper. The obtained‐products were characterized by inductively coupled plasma (ICP), X‐ray diffraction (XRD), high‐resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM). The results show that Ni particles in Ni/TiO₂ nanoparticles exhibit better dispersion and the size of most Ni particles is 10 nm or so. The catalytic activity of Ni/TiO₂ nanoparticles on the thermal decomposition of ammonium perchlorate (AP) was investigated by simultaneous thermogravimetry and differential thermal analysis (TG‐DTA). Results show that composite process of Ni and TiO₂ can improve the catalytic activity of Ni nanoparticles on the thermal decomposition of AP, which is mainly attributed to the improvement of Ni dispersion in Ni/TiO₂ nanoparticles. The catalytic activity of Ni/TiO₂ nanoparticles increases with increasing the weight ratio of Ni to AP.     

Synthesis, Thermal, Electrical and Catalytic Studies of Some Transition Metal Polychelates of Bis-bidentate Schiff Base

Polychelates of Mn（Ⅱ）, Fe（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Zn（Ⅱ） and Cd（Ⅱ） with the bis salen-type ligand derived from 4,4＇-bis[（salicylaldehyde-5）azo]biphenyl and 1,4-diaminobutane have been synthesized. All the polychelalls have been characllrized by elemental analysis, magnetic susceptibility measurements, IR, electronic spectra and thennogravirncuic studies. All the complexes isolated in solid stall are dark coloured and insoluble in water and common organic solvents. The ligand behaves as a bis-bidentall molecule coordinating through the phenolic oxygen and azomethine nitrogen atoms. The thermal decomposition of these metal complexes was investigated by thermogravimetric analysis and data have been analyzed for kinetic parameters using Broido equation. The solid-state electrical conductivity of the ligand and its polychelalls in the form of compressed pellet was studied in the temperaturc range from 313 to 413 K All the polychelalls were found to show semiconducting nature. The Mn（Ⅱ）, Fe（Ⅱ）, Co（Ⅱ） and Ni（Ⅱ） polychelalls have been assessed for the catalytic epoxidation of styrene.     

锂空气电池空气电极LiCoO2电催化性能研究

自设计建立锂空气电池实验装置,研究以掺入LiCoO2作为电催化剂的空气正极的电化学性能及其放电前后催化剂结构的变化.循环伏安、XRD及充放电测试等表明,LiCoO2能够很大程度地改善空气电极的放电性能.尤其是在放电前,将掺有LiCoO2的空气正极充电至4.1 V,此时LiCoO2的Co元素呈现较高的价态（Co3＋/Co...     

十二烷基硫酸钠与甜菜碱在气液和油水界面的复配协同作用研究

研究了十二烷基硫酸钠（SDS）和甜菜碱（Betaine）以及复配体系在油水界面和气液界面的排布行为,探讨了温度、无机盐和复配比例对表面活性剂界面活性和泡沫稳定性的影响,重点探讨了多价无机阳离子对表面活性剂界面吸附行为和复配协同加合增效作用的影响,得到了海水为介质条件下两方面性能均较好的体系,取得的认识为高盐条件下低张力泡沫驱油体系的设计与应用提供理论依据和指导.     

沙冬青抗冻蛋白热滞活性的DSC研究

在某些极地鱼类的血清以及某些昆虫和植物中 ,人们发现了一类特殊的物质 .它们的共同特点是能通过直接与冰晶核相互作用,抑制冰晶核的形成和生长,从而降低溶液冰点 .现已发现的这类抗冻物质都属于蛋白质,被统称为抗冻蛋白（ Antifreeze Proteins, AFPs） .抗冻蛋白能以非依数性形式大大降低溶液的冰点,但对熔点的影响很微弱,而且遵从依数性的原则,使冰点低于平衡态的熔点,溶液处于反常的非平衡相变状态 .这种冰点低于熔点的特性称为热滞 (Hysteresis).因此,抗冻蛋白也叫热滞蛋白或温度迟滞蛋白（ Thermal Hysteresis Proteins, …     

多相催化反应原位红外系统及其应用

设计和建立了一套能耐高温的用于多相催化反应研究的原位红外系统，反应温度从室温到１１５０Ｋ，系统真空为１．０＊１０＾５－１．０－１０＾－４Ｐａ，红外光谱检测范围为４８００－２００ｃｍ＾－１。此系统扩展了原仪器的功能，提高了仪器利用率和效率。     

柱状Co3O4催化剂的乏风催化燃烧性能

通过两步法成功合成了由纳米粒子组装成的柱状Co₃O₄。第一步是通过简单的冷凝回流法合成柱状CoC₂O₄·2H₂O。第二步将所制备的柱状CoC₂O₄·2H₂O在350℃下煅烧2 h,使其分解形成Co₃O₄而不破坏原始形貌。通过粉末X射线衍射（PXRD）,X射线光电子能谱（XPS）,氮气吸附－脱附,扫描电镜（SEM）,高分辨率透射电子显微镜（HRTEM）和H₂程序升温还原（H₂-TPR）表征柱状Co₃O₄的物化性质。结果表明,柱状Co₃O₄对乏风甲烷燃烧的催化活性远远高于商业Co₃O₄。柱状Co₃O₄优异的催化性能可能归因于其表面较高的Co³⁺含量,较高的表面吸附氧和大量暴露的{111}晶面族。     

胍盐离子液体的研究进展

胍盐离子液体由于具有较高的热稳定性、化学稳定性和催化活性而受到关注. 总结了近年来胍盐离子液体的合成、性质和应用三个方面的研究进展.     

Effect of the composition of titanium-zirconium oxide systems on their photocatalytic activity in the reduction of methylene blue by formaldehyde

Relationships were obtained between the photocatalytic activity (PCA), absorption spectra, electrical conductivity (σ), and catalytic activity (CA) of oxides containing Zr⁴⁺ and Ti⁴⁺ and their quantitative and phase composition. It was found that the PCA and CA depend linearly on σ. The relation between these characteristics and the effectiveness of their action in chemical reactions was studied. __________ Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 42, No. 6, pp. 345–350, November–December, 2006.     

Silica Supported and Conventional Approaches for the Synthesis of Carbonyl Diimidazole Type of Ionic Liquids and Its Catalytic Activities

Synthesis of carbonyl diimidazole type of ionic liquids via silica supported and conventional methodologies under muffle furnace and refluxing condition, respectively, to give shorter reaction time and higher yield. We have studied the catalytic activities of our synthesized ionic liquids for polymerization reactions.     

Estimation of the activity of catalysts and the reactivity of organosulfur compounds

The kinetics of hydrogenolysis of various classes of organosulfur compounds were studied in the presence of MeAlCl ₄ catalysts (Me=Li, Na, K). The reactions were conducted at 100–250°C without introduction of hydrogen into the reaction zone, but in the presence of hydrocarbons capable of acting as hydride—ion donors; these donors were necessary for H ₂ S formation. A series of catalytic activities and optimal reaction conditions for each catalyst were determined from the rate constants of hydrogenolysis at the C-S bond. Reactivities of mercaptans, sulfides, disulfides, and thiophene were estimated.Institute of Chemistry, Bashkir Scientific Center, Ural Branch, Russian Academy of Sciences, Ufa 450054. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 562–564, March, 1992.     

两相催化体系中长链烯烃氢甲酰化反应研究进展

水溶性有机金属络合物为催化剂的两相催化体系,由于反应条件缓和,产物和催化剂分离简便等特点,已成为发展环境友好的绿色化学的重要方向。本文介绍了近年来两相催化体系中长链烯烃氢甲酰化反应和催化剂研究进展。     

消旋卡多曲在空气中的热分解动力学

用热分析(TG/DTA/DSC)技术研究了消旋卡多曲(C₂₁H₂₁NO₄S)在空气中的热分解过程. 热分析结果表明, 消旋卡多曲在空气中一步分解, 其熔点为77.4 ℃. 用Friedman法, Flynn-Wall-Ozawa (FWO)法和ASTM E698法求取了分解过程的活化能E, 并通过多元线性回归法给出了可能的机理函数.     

两相体系中钌膦配合物催化4—苯基—3—丁烯—2—酮加氢反应的研究

研究了水和有机物组成的两相催化体系中,由ＲｕＣｌ３－ＴＰＰＴＳ（ＴＰＰＴＳ：Ｐ（ｍ－Ｃ６Ｈ４ＳＯ３Ｎａ）３）原位反应生成的催化活性物种对４－苯基－３－丁烯－２－酮（又名苄叉丙酮）的催化加氢反应．考察了钌浓度（１．０×１０－３～６．０×１０－３ｍｏｌ／Ｌ）、氢压（１．０～６．０ＭＰａ）、反应温度（３０～７０℃）、配体浓度（１．２～７．２×１０－２ｍｏｌ／Ｌ）、阳离子表面活性剂（ＣＴＡＢ：十六烷基三甲基溴化铵）及反应时间等对加氢反应活性和选择性的影响,并与以配合物ＲｕＣｌ２（ＴＰＰＴＳ）３为催化剂前体生成的催化活性物种对加氢反应的活性及选择性进行了比较．结果表明,分别由配合物ＲｕＣｌ２（ＴＰＰＴＳ）３及ＲｕＣｌ３－ＴＰＰＴＳ原位反应生成的催化活性物种,都只催化４－苯基－３－丁烯－２－酮的Ｃ＝Ｃ键选择加氢．由配合物ＲｕＣｌ２（ＴＰＰＴＳ）３形成的催化体系的加氢活性及选择性均优于ＲｕＣｌ３－ＴＰＰＴＳ原位反应生成的催化活性物种．阳离子表面活性剂的加入,使加氢反应活性下降,选择性略有提高     

Kinetics of the Thermal Decomposition of Magnesium Salicylate Powder in Air

IntroductionThe chelate complexes of salicylic acid with rareearth and alkali earth ions have attracted considerableattention because of their special antibacterial proper-ties[1—3].The study of the thermal degradation of metalsalicylates is of major int…