尿碘的流动在线消化催化光度法测定

将尿样消化引入ＦＩＡ流路，并与催化光度法相结合，建立了尿碘的流动在线消化催化光度法，从而实现了尿碘的快速自动测定。本法分析速度１３０／ｈ，检测范围宽达４０～１６００μｇ／ＬＩ＾－，重现性好，实际尿样测定ＲＳＤ≤６．９％（ｎ＝８），方法具有创新和实用性，对尿碘的快速准确定值及碘缺乏病的防治有重要意义。     

半导体催化膜上泵氧甲烷氧化偶联反应的研究 Ⅱ.联合体系的反应

在常压及６５０℃下，以含１％Ｏ２的甲烷－氧混合气进料，考察了在ＣａＯ，ＳｒＯ，ＺｎＯ，ＴｉＯ２，ＣｅＯ２和ＭｎＯ２膜上外加电流为－９０～９０ｍＡ范围内联合体系的甲烷氧化偶联反应，结果表明，在ｐ型和ｎ型半导体催化膜上，发生ＮＥＭＣＡ效应的增强因子有一极值，联合体系中泵氧ＯＣＭ反应的Ｃ２烃选择性低于开路体系中反应的Ｃ２烃选择性，根据总反应速率求出了总传递系数及电化学影响效率，电化学影响效率随ｎ型电导率     

Catalytic Hydrogenation of Diacetyl Monoxime to Tetramethylpyrazine with the Soluble Transition Metal Catalysts

Tetramethylpyrazine(TMP)isausefulcompoundinfoodindustry'.InrecentyearsithasbeenfoundasanactiveingredientinChuanxi0ng(ligusticumwallichiifranch),whichisatraditionalChineseherb.NowTMPhasbeenwidelyusedinthetreatmentofpatientswithcerebralischemicdiseasesinChina2.OneoftheimportantmethodsforthepreParationoftetramethylpNazineistheselfcondensati0noftwomoleculesof2-aminobutanoneto2,5-dihydrotetramethlipyrazineandsubsequentoxidati0ntoTMP3.2-Aminobutanoneispreparedusuallyinsituviathereductionofthec…     

Competitive Transfer Hydrogenation of Unsaturated Alcohol-Alkene-Diene Systems

The paper describes hydrogenation of unsaturated alcohols, alkenes and dienes in individual and binary systems of substrates by use of catalytic hydrogen transfer from ammonium formate in methanol on a palladium catalyst. A significant structural effect of hydrogenated alcohols upon their reactivity and adsorptivity was observed. Following comparison to the data acquired from typical hydrogenation by use of molecular hydrogen, it was inferred that the components of the CTH system increase the selectivity of competitive transfer hydrogenation to a significant extent in systems of unsaturated alcohol — unsaturated hydrocarbon with regard to the relative increase of reactivity of unsaturated alcohols. This occurs primarily due to affecting the relative adsorptivity.     

水杨酸抑制亚硝酸根催化鸡冠花红褪色反应的伏安法研究及其应用

用两阶导数未波极谱法作监测技术研究了水杨酸对ＮＯ２＾－催化ＢｒＯ３＾－氧化鸡冠花工褪色反应的抑制行为，测定了该抵制体系的反应级数、动力学方程及表观活化能，建立了动力学抑制法测定水杨酸的新方法。方法的线性范围为０．０５～０．６５ｍｇ／Ｌ，检测限为０．０２６ｍｇ／Ｌ，与已报道的各种水杨酸测定方法相比，该法具有仪器简单、操作方便、灵敏度较高等优点。用于爽肤水与润肤露中微量水杨酸的测定。结果满意。     

Enzyme Models—From Catalysis to Prodrugs

Enzymes are highly specific biological catalysts that accelerate the rate of chemical reactions within the cell. Our knowledge of how enzymes work remains incomplete. Computational methodologies such as molecular mechanics (MM) and quantum mechanical (QM) methods play an important role in elucidating the detailed mechanisms of enzymatic reactions where experimental research measurements are not possible. Theories invoked by a variety of scientists indicate that enzymes work as structural scaffolds that serve to bring together and orient the reactants so that the reaction can proceed with minimum energy. Enzyme models can be utilized for mimicking enzyme catalysis and the development of novel prodrugs. Prodrugs are used to enhance the pharmacokinetics of drugs; classical prodrug approaches focus on alternating the physicochemical properties, while chemical modern approaches are based on the knowledge gained from the chemistry of enzyme models and correlations between experimental and calculated rate values of intramolecular processes (enzyme models). A large number of prodrugs have been designed and developed to improve the effectiveness and pharmacokinetics of commonly used drugs, such as anti-Parkinson (dopamine), antiviral (acyclovir), antimalarial (atovaquone), anticancer (azanucleosides), antifibrinolytic (tranexamic acid), antihyperlipidemia (statins), vasoconstrictors (phenylephrine), antihypertension (atenolol), antibacterial agents (amoxicillin, cephalexin, and cefuroxime axetil), paracetamol, and guaifenesin. This article describes the works done on enzyme models and the computational methods used to understand enzyme catalysis and to help in the development of efficient prodrugs.     

燃料电池中Pt基催化剂对CO的催化氧化

燃料电池具有燃料多样性、噪声低、对环境污染小等优势,近年来备受研究者关注。然而,电池中的贵金属催化剂极易被少量的CO毒化,成为制约其商业化的一大障碍。因此,设计出高性能的催化剂对于推动燃料电池的发展十分关键。本文综述了燃料电池中铂(Pt)基催化剂对CO催化氧化的研究现状,首先探讨了CO催化氧化机理以及CO在Pt金属表面化学吸附的机理,其次详细介绍了Pt负载型催化剂、双金属催化剂以及助催化剂在催化反应中的不同作用,然后简单分析了影响Pt基催化剂性能的其他因素。最后,对燃料电池中Pt基催化剂的研究方向作了进一步的展望,旨在为燃料电池中CO催化氧化的发展开拓新思路。     

团簇Ni4P催化析氢性能研究

为探究团簇Ni₄P催化析氢最强的结构,基于密度泛函理论,在B3LYP/Lan12dz水平下,对团簇Ni₄P的初始构型进行计算和优化,得到5种优化构型。从热力学稳定性、前线轨道图和前线轨道能级差对团簇Ni₄P的析氢性能分析发现,构型1^（4）和1^（2）的热力学稳定性较强;团簇Ni₄P各优化构型均易吸附水中的氢原子,Ni原子为团簇Ni₄P催化活性位点,且构型1^（4）、1^（2）和2^（4）催化析氢的活性更强。(1^（2）)-H、(2^（2）)-H在电化学脱附法和化学重组法中均具有较强的催化活性。以上说明构型1^（2）是团簇Ni₄P催化析氢最强的结构。     

金属纳米团簇(MNCs)的性能与应用*

金属纳米团簇(metal nanoclusters,MNCs)是由几个到几百个金属原子组成的内核被单层配体保护而形成的一类新型材料。MNCs的结构可在原子级精度的水平上进行调控,因其具有超小的尺寸、独特的电子能级以及大的比表面积等性质而获得了广泛的应用。主要基于ds区金属铜、银、金的纳米团簇 (CuNCs、AgNCs、AuNCs) 的相关研究介绍MNCs的概念、结构特征、主要性能、合成策略以及它们在催化、生物传感、生物成像和肿瘤治疗中的应用。