层状钨基氧化物复合材料的合成与电子特性

W₂O₆·H₂O /一元烷基胺复合物[(C_nH_2n+1NH₂，n=4、8、12、16)嵌入层状氧化钨W₂O₆·H₂O] 的XRD、IR、TG-DSC分析表明：烷基胺C_nH_2n+1NH₂能基于质子加合的机制嵌入W₂O₆·H₂O层间，且插层复合物之间烷基胺的插入与抽出是个可逆过程；烷基胺嵌入层间后以全反式构象双层排布，层间距d随烷基胺碳原子数的增加而线性增长，烷基链与层板的夹角为71.6°。插层复合物UV-Vis分析发现，各种复合物的禁带宽度相对半导体氧化钨的禁带宽度变宽了很多，这表明可以通过嵌入不同的物质来调节氧化钨层与层之间的电子传递能力。     

In-Situ Synthesis and Characterization of Nanocomposites in the Si-Ti-N and Si-Ti-C Systems

The pyrolysis (1000 °C) of a liquid poly(vinylmethyl-co-methyl)silazane modified by tetrakis(dimethylamido)titanium in flowing ammonia, nitrogen and argon followed by the annealing (1000–1800 °C) of as-pyrolyzed ceramic powders have been investigated in detail. We first provide a comprehensive mechanistic study of the polymer-to-ceramic conversion based on TG experiments coupled with in-situ mass spectrometry and ex-situ solid-state NMR and FTIR spectroscopies of both the chemically modified polymer and the pyrolysis intermediates. The pyrolysis leads to X-ray amorphous materials with chemical bonding and ceramic yields controlled by the nature of the atmosphere. Then, the structural evolution of the amorphous network of ammonia-, nitrogen- and argon-treated ceramics has been studied above 1000 °C under nitrogen and argon by X-ray diffraction and electron microscopy. HRTEM images coupled with XRD confirm the formation of nanocomposites after annealing at 1400 °C. Their unique nanostructural feature appears to be the result of both the molecular origin of the materials and the nature of the atmosphere used during pyrolysis. Samples are composed of an amorphous Si-based ceramic matrix in which TiN_xC_y nanocrystals (x + y = 1) are homogeneously formed “in situ” in the matrix during the process and evolve toward fully crystallized compounds as TiN/Si₃N₄, TiN_xC_y (x + y = 1)/SiC and TiC/SiC nanocomposites after annealing to 1800 °C as a function of the atmosphere.     

Synthesis,Reactions, and Spectral Characterization of New Fused Pyrazolothienopyridine and Pyrazolopyrrolopyridine Systems

4‐Oxo‐1‐phenyl‐4,7‐dihydropyrazolo[3,4‐b ]pyridine‐5‐carbonitrile compound ( 4 ) was prepared by the reaction of 5‐amino‐3‐methyl‐1‐phenyl pyrazole ( 1 ) with ethyl 2‐cyano‐3‐ethoxyacrylate followed by cyclization using diphenyl ether. The pyrazolopyridinone compound 4 was converted to the chloropyrazolopyridine 5 by the reaction with phosphorus oxychloride. Compound 5 was used as a starting material to synthesize 3‐amino‐4‐substituted pyrazolothienopyridine derivatives 10a–f and ethyl‐3‐aminopyrazolopyrrolopyridine‐2‐carboxylate 21 , which were used as a versatile precursors for synthesis of poly‐fused heterocyclic compounds.     

Modified Ceria-Zirconia Fluorite-Like Catalysts for the Combustion of Methane

For dispersed ceria-zirconia-based solid solutions prepared via the polymerized complex method and annealed at 700℃, effects of bulk doping by Ca, Mn, Co, Bi or Nb cations and surface modification by Mn and Pt on their structural features, surface/bulk oxygen reactivity and catalytic activity in methane combustion are considered. With up to 20 mol% doping, a structural type of homogeneous solid solutions of anion-deficient fluorite with disordered anion vacancies is formed. Doping by transition metal cations or Pt increases the mobility and reactivity of the surface/bulk oxygen. A broad variation in specific rates of methane combustion for the studied systems was observed, suggesting structural sensitivity of this reaction. In general, there is no universal relationship between the oxygen mobility, the reactivity and the catalytic activity in methane combustion, which is explained by the factor of specific methane activation on surface active sites. For the Pt-promoted samples, Pt efficiency in methane activation depends on the Pt-support interaction, and the most favorable ones being mixed Pt/MnOx and Pt/NbOx clusters on the surface of the supports that exhibit high lattice oxygen mobilities.     

在离子液/水体系中超声合成MoO_3纳米棒及其表征(英文)

采用超声波的方法在离子液(1-丁基-3-甲基氯代咪唑盐离子液,[BMIM]Cl)中合成了直径分布在80~150 nm的MoO3纳米棒.采用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、场发射扫描电子显微镜(FESEM)、高分辨透射电子显微镜(HRTEM)和选区电子衍射(SAED)对所合成材料的微观结构和形貌进行了表征.此外,考察了反应时间、加入[BMIM]Cl的量以及其它咪唑基离子液对产物的影响并提出了可能的反应机理.最后对在不同温度煅烧下所得的α-MoO的甲烷催化燃烧活性进行了表征.     

Synthesis and Characterization of New Polymer Systems Containing 4‐Silylmethylstyrene Units

A series of terpolymers containing silyl pendant groups were prepared by free radical cross‐linking copolymerization. Et₃Si and HMe₂Si were covalently linked with 4‐vinylbenzyl and abbreviated as TESiMSt and DMSiMSt, respectively. Et₃Si was covalently linked with 2‐hydroxyethyl methacrylate (HEMA). The silyl‐linked HEMA are abbreviated as TESiEMA. Free radical terpolymerization of the methacrylic acid (MAA) with different molar ratios of organosilyl monomers was carried out at 60–70 °C. The compositions of the polymers were determined by FT‐IR spectroscopy and ¹H‐NMR. The glass transition temperature (Tg) of the polymers was determined calorimetrically. The study of DSC curves showed that incorporation of monomers with cyclic units in polymer chains increases the rigidity of terpolymers and the Tg value is subsequently increased.     

Synthesis,Structural Characterization,and Electrochemical Properties of Isotruxene–Polyaniline Hybrid Systems

The synthesis, structural characterization, and electrochemical properties of a series of isotruxene–polyaniline (PANI ) hybrid systems (SITPs , SITAs , and CITs ) are reported. The syntheses were performed by in situ chemical oxidative polymerization of aniline in the presence of isotruxene additives ITP and/or ITA at specific aniline‐to‐additive molar ratios. The polymers SITPs and SITAs display granular morphology, but for the polymers CITs a spherical morphology with a diameter of 300–500 nm is found. These hybrid systems display electrochemical capacitive performance superior to those of the parent PANI prepared under the same condition (e.g., 385–463 vs. 181 F/g at 3 mA /cm² current density during charge–discharge test). Molecular (star‐shaped or hyperbranched vs. linear topology) and supramolecular (isotruxene–PANI π–π and cation–π interactions) models in accounting for the observed morphology and electrochemical properties are provided.     

Synthesis,Characterization, and Electronic Structures of Porphyrins Fused with Polycyclic Aromatic Ring Systems

A series of porphyrins fused with acenaphthylene, phenanthroline, and benzofluoranthene polycyclic aromatic rings were prepared by means of a 3+1 porphyrin synthesis approach and subsequent retro‐Diels–Alder reaction of bicyclo[2.2.2]octadiene‐fused precursors. Analysis of the magnetic circular dichroism spectra and the results of time‐dependent DFT calculations are used to identify the reasons for the trends observed in the wavelengths and relative intensities of the Q bands of the products. Michl's perimeter model is used as a conceptual framework to explain the changes in the relative energies of the frontier π‐molecular orbitals.     

Multicomponent Molecular Systems Based on Porphyrins, 1,3,5-Triazine and Carboranes: Synthesis and Characterization

2,4,6-Trichloro-1,3,5-triazine (cyanuric chloride) is an excellent coupling reagent for the preparation of highly structured multifunctional molecules. Three component systems based on porphyrin, cyanuric chloride and carborane clusters were prepared by a one-pot stepwise amination of cyanuric chloride with 5-(4-aminophenyl)-10,15,20-triphenylporphyrin, followed by replacement of the remaining chlorine atoms with carborane S- or N-nucleophiles. Some variants of 1,3,5-triazine derivatives containing porphyrin, carborane and residues of biologically active compounds such as maleimide, glycine methyl ester as well as thioglycolic acid, mercaptoethanol and hexafluoroisopropanol were also prepared. A careful control of the reaction temperature during the substitution reactions will allow the synthesis of desired compounds in a good to high yields. The structures of synthesized compounds were determined with UV-vis, IR, ¹H NMR, ¹¹B NMR, MALDI-TOF or LC-MS spectroscopic data. The dark and photocytotoxicity as well as intracellular localization and photoinduced cell death for compounds 8, 9, 17, 18 and 24 were evaluated.     

对羟基苯氧基蒽醌的合成与表征

合成了两种新的光致变色化合物1-羟基-4-苯氧基-9,10-蒽醌及1-羟基-4-对氯苯氧基-9,10-蒽醌,并通过核磁共振谱、红外光谱、质谱和元素分析确定了其结构。通过紫外-可见光谱表征了其光致变色性,并讨论了结构对光致变色性的影响。     

O—丁烷基壳聚糖的合成与表征

通过西夫碱中间体合成了Ｏ－丁烷基壳聚糖。用苯甲醛与壳聚糖反应形成了苄叉壳聚糖,再用氯丁烷与之反应,之后用稀乙醇盐酸溶液处理移去西夫碱－衍生物的结构用元素分析,ＩＲ和Ｘ－射线衍射进行了表征,在壳聚糖分子的Ｃ２和Ｃ５位上引入不同基团,削弱了分子间的作用力,进一步增强了溶解性。     

甲壳胺-g-PEG的合成及医用性能的研究(Ⅰ)甲壳胺-g-PEG的合成及表征

通过官能团偶联反应，将端基改性为醛基的甲氧基聚乙二醇（分子量分别为２０００、５０００），按不同配比与甲壳胺反应，制得了甲壳胺接枝ＰＥＧ的产物（Ｃｈｉｔｏｓａｎ－ｇ－ＰＥＧ）。讨论了反应的最佳ｐＨ条件。建立了有效的产物分离方法，用红外光谱法、１Ｈ－ＮＭＲ法对产物的本体结构进行了表征，并用元素分析法和１Ｈ－ＮＭＲ法对接枝量进行了测定。     

镁离子型Birnessite的合成和表征

采用ＭｎＯ－４和Ｍｎ２＋在强碱性条件下制得层状结构的Ｍｇ＿Ｂｉｒｎｅｓｓｉｔｅ，用ＸＲＤ（Ｘ射线多晶粉末衍射）、ＦＴ－ＩＲ（傅里叶红外光谱）、ＴＧ－ＤＴＧ／ＤＴＡ（热失重－微商热失重／热分析）等方法对它进行了表征。Ｍｇ＿Ｂｉｒｎｅｓｉｔｅ在２００～４００℃时为无定形，在６００℃生成结晶良好的Ｍｎ２Ｏ３相。ＣＣｌ４、ＣＨ３ＯＨ、ｎ＿Ｃ６Ｈ１４的吸附等温线类似于第三种类型的吸附等温线，在接近饱和的情况下都有凝聚现象产生。在６００℃，比表面和吸附数据表明出现层状结构塌陷。吸附吡啶ＦＴ－ＩＲ谱表明在Ｍｇ＿Ｂｉｒｎｅｓｉｔｅ中存在非质子酸（Ｌ酸）和质子酸（Ｂ酸）酸位。     

Synthesis and Characterization of Altaicadispirolactone

Altaicadispirolactone was synthesized via a simple route. In this route, levulinic acid was used as a starting material, and bromination followed by hydrolysis and BF₃ · OEt₂‐catalyzed cyclization were carried out. A single‐crystal ORTEP drawing has been created and more detailed crystallographic data of the compound has been obtained from X‐ray analysis.     

苯胺低聚体的合成与表征

苯胺低聚体从结构上可分为三种类型,即苯／胺,双胺和双苯封端的苯胺低聚体。本文从这三种结构出发综述了近几年来苯胺低聚体的合成与光谱表征。     

二吡唑基甲酮类化合物的合成和表征

以5-氨基-3-甲硫基-1H-吡唑-4-羧酸乙酯(1)为原料, 依次经肼解、与取代的乙烯酮二硫缩醛缩合和烷基化合成了一系列二吡唑基甲酮类化合物, 经¹H NMR, ¹³C NMR和元素分析确证了它们的结构, 部分化合物进一步经过了质谱表征.     

三苯基锗二硫代氨基甲酸酯的合成及表征

近年来 ,人们相继合成了有机锗倍半硫化物、有机锗硫杂环戊酮、含硫的螺环有机锗等化合Scheme1　 Synthetic route of compound物[1,2 ] .但烃基锗二硫代氨基甲酸酯类化合物尚未见报道 .我们 [3,4 ] 发现 ,有机锡二硫代氨基甲酸酯类化合物有很强的生物活性 .鉴于有机锗化合物比有机锡化合物毒性低得多 ,且副作用小 ,我们以三苯基氯化锗和二硫代氨基甲酸盐为原料 ,合成了一系列新型的有机锗含硫衍生物 (反应式如Scheme1所示 ) ,并对其结构进行了表征 ,初步生物活性测试结果表明 ,部分化合物显示出较强的抗癌活性 .1　实　　验1 .1　仪器与…     

Synthesis and Characterization of Multithiouracils

Alkylation of bases group of nucleic acid, thymine and uracil, has attracted great attention. In order to investigate the intermolecular interactions, [1,2] and the photoreactions[3,4] between bases group of nucleic acid, many studies were focused on the synthesis of bisbases in the formation of B-(CH2)n-B (B′) in which trimethylene was commonly used as linker. Thiouracil is an important derivative of nucleic acid bases, and it can interfere with the synthesis of thyroxine, especially in the treatment of hyperthyroidism and angina. However, to our knowledge, the synthesis of bisthiouracils, even trithiouracils, using flexible or rigid linkers has not been reported. Herein, we have synthesized eight thiouracil derivatives by nucleophilic reaction between thiouracil and varied bromides. All the compounds have been characterized by IR, 1H NMR and element analysis.