不同代数超支化聚胺酯的制备及其在钕纳米粒子制备中的应用

以N，N-二羟乙基-3-胺基丙酸甲酯单体和季戊四醇（核）为原料，采用“准一步法”合成了具有端羟基的超支化聚胺酯（HPAE）。采用凝胶色谱、红外光谱、核磁共振和热重分析等对其进行了结构表征及性能探究。再以HPAE封装稀土粒子钕（Nd），制备出Nd复合纳米粒子，透射电镜（TEM）分析结果表明：随着HPAE代数增大，Nd纳米颗粒粒径越均匀，分散度越好。     

镧系离子与L-羟脯氨酸、DL-瓜氨酸配位作用研究

稀土与体内广泛存在的生物配体氨基酸的配位作用，尤其是三元体系的研究对于阐明稀土元素在体内的存在形态及探索稀土生物效应具有重要意义．羟脯氨酸和瓜氨酸均是人体中存在的重要氨基酸，它们在人体血浆中的浓度与必需的氨基酸相近［‘j．稀土与氨基酸配位作用的研究已有较多报道「’‘，但模拟生理条件下稀土离子与羟脯氨酸、瓜氨酸的二元、三元配合物的PH电位法研究尚未见报道．本文报道在模拟生理条件下（37C，0·15mol／LNaCI）湖系离子（Pm和Lu除外）与上述2种氨基酸的二元及三元配合物PH电位法研究结果．1实验部分1．1试剂和仪…     

蝎型钒氧配合物的合成、结构及量子化学研究

设计合成了两种新型的以聚类吡唑硼酸盐为配体的钒氧配合物VO(acac)[HB(pz)3](1)和VO(acac)[HB(3,5-Me2pz)3]·CH3CN(2). 运用元素分析、 红外光谱和紫外光谱对所合成的配合物进行了表征, 并用X射线衍射测定了它们的晶体结构. 同时, 采用量子化学的Hartree Fock方法和自然轨道分析方法(NBO), 使用3-21G*(6d, 7f)基组计算得到了两个分子体系的分子轨道、原子电荷以及键级, 并对其结构进行了分析.     

Expression ofAscaris suum malic enzyme in a mutantEscherichia coli allows production of succinic acid from glucose

Applied Biochemistry and Biotechnology - The malic enzyme gene ofAscaris suum was cloned into the vector pTRC99a in two forms encoding alternative arnino-termini. The resulting plasmids, pMEAl and...     

Ligand Exchange Between Penta-Coordinated Phosphoryl Serine and Histidine Compounds

With the assistance of HPLC-ESI-MS/MS, the self-assembly products of serine and histidine penta-coordinated phosphorus compound were separated and identified. The expectative product was seryl-histidine dipeptide, but it was found that there was almost equimolar amount of histidyl-histidine dipeptide as well as seryl-histidine dipeptide. The mechanism was speculated that there was iigand exchange between penta-coordinated phosphoryl serine and histidine in the reaction process. As a result,two types of dipeptide were produced.     

Collision-induced and infrared multiphoton dissociation studies on M(acetone)2 + (M=Al,Fe, Co,Cu, ScO) in the gas phase

In this paper we report an extension of our earlier study on the structure of Alfacetone)₂ ⁺ Collision-induced dissociation (CID) on MfacetoneXacetone-d₆)⁺ for M = Al, Fe, Co, and Cu yields primarily, if not exclusively, nearly equal amounts of acetone and acetone-d₆. Likewise, infrared multiphoton dissociation (IRMPD) at 10.6 μm yields, exclusively, nearly equal losses of the labeled and unlabeled acetones. These results suggest that the two acetone ligands bind in an equivalent fashion. Sc⁺ was also studied, which proved to be the most interesting. Sc⁺ reacts with acetone to form primarily ScO⁺, which undergoes higher order reactions leading to several products including ScO(acetone)₂ ⁺. IRMPD on this ion produces ScO(acetone-d₆)(CD₂CO)⁺, while its perdeuterated analog also produces ScO(acetone-d₆)⁺ in addition to ScO(acetone-d₆(CD₂CO)⁺. The IRMPD results are supplemented by studying the primary and higher order reactions of Sc⁺ with acetone, as well as the CID of ScO(acetone)₂ ⁺. Finally, a qualitative assessment of the infrared photodissociation cross sections is given. It is found that the relative photodissociation cross sections follow the orders Co(acetone-d₆)₂ ⁺ > Co(acetone)(acetone-d₆) > Co(acetone)₂ ⁺ and Co(acetone-d₆)⁺ > Co(acetone)⁺.     

Monolayers as models for supported catalysts: zirconium phosphonate films containing manganese(III) porphyrins

Organized monolayer films of a manganese tetraphenylporphyrin have been prepared and used as supported oxidation catalysts. Manganese 5,10,15,20-tetrakis(tetrafluorophenyl-4'-octadecyloxyphosphonic acid) porphyrin (1) has been immobilized as a monolayer film by a combination of Langmuir-Blodgett (LB) and self-assembled monolayer techniques that use zirconium phosphonate linkages to bind the molecule to the surface. Analysis by FTIR, XPS, UV-vis and polarized optical spectroscopy show that the films consist of noninteracting molecules effectively anchored and oriented nearly parallel to the surface. The monolayer films are stable to the solvent and temperature conditions needed to explore organic oxidations. The activity of films of 1 toward the epoxidation of cyclooctene using iodosylbenzene as the oxidant was compared to that of Manganese 5,10,15,20-tetrakis(pentafluorophenyl) porphyrin (2) and 1 under equivalent homogeneous conditions. The immobilized porphyrin 1 shows an enhanced activity relative to either homogeneous reaction. The main difference between 1 and 2 is the four alkyl phosphonate arms in 1 designed to incorporate the porphyrin within the films. The increased activity of immobilized 1 is a combination of the porphyrin structure, which prohibits the formation of mu-oxo dimers even in solution, and a change in conformation when anchored to the surface. The study demonstrates that careful monolayer studies can provide useful models for the design and study of supported molecular catalyst systems.     

Synthesis,crystal structure and characterization of a 2-D network organic-inorganic hybrid polymer with α-BW_(12)O_(40) ~(5-) as building blocks

A two-dimensional network compound [Ce(DMF)4(H2O)][α-BW12O40]·H2O·(HDMA)2 (HDMA = protoned dimethylamine, DMF = N,N-dimethylformamide) was synthesized from α-H5BW12O40·nH2O, Ce(NO3)3·6H2O and DMF and characterized by IR, UV spectra and TG-DTA. The result of the X-ray single crystal diffraction indicates that the crystal is monoclinic, space group P21/n, with unit cell dimensional: a = 1.1983(3), b = 2.4216(5), c = 1.9517(4) nm, β = 92.91(3)°, Z = 4, R1 = 0.07710, wR2 = 0.1416. Structural analysis indicates that every [Ce(DMF)4(H2O)]3 building block is surrounded by three adjacent [α-BW12O40]5- polyanions, meanwhile, every [α-BW12O40]5- polyanion interconnects with three neighboring [Ce(DMF)4(H2O)]3 subunits, by making use of which two-dimensional network structure can be constructed. The result of thermogravimetric analysis manifests that the title compound has two-stage weight loss and the decomposition temperature of the title polyanionic framework is 560℃ . The electrochemical analysis shows the title polyanion has three-step redox processes in the pH = 4―7 media.     

X射线荧光光谱法分析玻璃纤维中主、次量元素成分

采用粉末压片-波长色散X射线荧光光谱法分析了中碱及无碱玻璃纤维中硅、铝、钙、镁、铁、钛、钾、钠、砷、氟等10种主、次量元素成分含量。以6个标准样品并结合两个参考样品建立校准曲线，采用DeJongh模式方程有效校正玻璃基体中元素间的吸收增强效应和重叠效应。该方法测定10个元素的精密度和准确度均较好，其相对标准偏差在0．35％～2．86％之间，对实际样品的分析结果与化学法相吻合，可应用于玻璃纤维中多元素成分的快速分析。