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951.
952.
Ali Grinou Hyeonseong Bak Young Soo Yun 《Journal of Dispersion Science and Technology》2013,34(5):750-755
A simple method was used to synthesize the hybrid nanocomposites consisting of the functionalized multiwalled carbon nanotube composites (MWCNTs) with the polyaniline incorporated silver nanoparticles (a-MWCNT/PANI-Ag) through an emulsion polymerization at room temperature in order to enhance the electrical conductivity of polyaniline. The electrical conductivity of the composite with the incorporated Ag nanoparticles was 5% higher than the same weight percent for the composite without Ag nanoparticles, and the thermal stability was dramatically increased from 54% for the composite (a-MWCNT/PANI) to 69% through the incorporation of the Ag nanoparticles at 830°C. Additionally, the advantages of the Ag nanoparticles, including the improved electrical and thermal properties without damage to the polyaniline structure, were confirmed using FTIR and Raman spectroscopy. 相似文献
953.
M. B. Babanly L. F. Mashadieva G. M. Velieva S. Z. Imamalieva Yu. M. Shykhyev 《Russian Journal of Electrochemistry》2009,45(4):399-404
The EMF method with a solid Ag4RbI5 superionic conductor was used to study the Ag-As-Se and Ag-S-I systems in the composition ranges of Ag2Se-As2Se3-Se and Ag2S-AgI-S, accordingly. Their solid-phase equilibrium diagrams are constructed or specified. The existence of ternary AgAs3Se5, AgAsSe2, Ag3AsSe3, Ag7AsSe6, Ag3SI compounds is confirmed. The standard partial and integral thermodynamic formation functions and also standard entropies were calculated for these compounds for the first time. 相似文献
954.
以硝酸银为银源,在硅片上成功地制备了银纳米线。该制备步骤在室温下操作,用环境友好的化合物乙二醇作还原剂。这是一个完全“绿色的”制备路线。用XRD、SEM和EDX对新制备的产物进行了表征,结果表明该银纳米线很纯,平均直径20nm。该银纳米线用于罗丹明6G的表面增强拉曼光谱测定,当罗丹明6G为10nM时,出现了特征峰。 相似文献
955.
Xian Tao Ke‐Cheng Shen Qing‐Yun Tang Meng Feng Jiang‐Tao Fang Yu‐Long Wang Ying‐Zhong Shen 《应用有机金属化学》2012,26(2):67-73
Six organophosphine/phosphite‐stabilized silver(I) N‐hydroxysuccinimide complexes of type [C4H4NO3Ag?Ln] (L = PPh3; n = 1, 2a; n = 2, 2b; L = P(OEt)3; n = 1, 2c; n = 2, 2 d; L = P(OMe)3; n = 1, 2e; n = 2, 2f) were prepared. These complexes were obtained in high yields and characterized by elemental analysis, 1H NMR, 13 C{1H} NMR and IR spectroscopy, respectively. The molecular structure of 2b has been determined by X‐ray single‐crystal analysis in which the silver atom is in a distorted tetrahedral geometry. An interstitial methanol solvent molecule is hydrogen bonded to the oxygen atom of N‐hydroxysuccinimide molecule. Complex 2f was used to deposit silver films by metal‐organic chemical vapor deposition (MOCVD) for the first time. The silver film obtained at 480 °C is dense and homogeneous, which is composed of many well‐isolated, granular particulates spreading all over the substrate surface. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
956.
Ruthenium(II), copper(I) and silver(I) complexes of large bite bisphosphinite Ph2P{(-OC10H6)(μ-CH2)(C10H6O-)}PPh2 (1) are described. Reactions of bisphosphinite 1 with [Ru(η6-p-cymene)(μ-Cl)Cl]2 and RuCl2(PPh3)3 afford mono- and bis-chelate complexes [RuCl(η6-p-cymene){η2-Ph2P{(-OC10H6)(μ-CH2)(C10H6O-)}PPh2-κP,κP}]Cl (2) and trans-[RuCl2{η2-Ph2P{(-OC10H6)(μ-CH2)(C10H6O-)}PPh2-κP,κP}2] (3), respectively. Treatment of 1 with CuX (X = Cl, Br and I) furnish 10-membered chelate complexes of the type [Cu(X){η2-Ph2P(-OC10H6)(μ-CH2)(C10H6O-)PPh2-κP,κP}] (4, X = Cl; 5, X = Br; 6, X = I), whereas [Cu(MeCN)4]PF6 affords a bis-chelated cationic complex [Cu{η2-Ph2P(-OC10H6)(μ-CH2)(C10H6O-)PPh2-κP,κP}2][PF6] (7). Reaction between 1 and AgOTf produce both mono- and bis-chelated complexes [Ag{η2-Ph2P(-OC10H6)(μ-CH2)(C10H6O-)PPh2-κP,κP}(SO3CF3)] (8) and [Ag{η2-Ph2P(-OC10H6)(μ-CH2)(C10H6O-)PPh2-κP,κP}2][SO3CF3] (9), respectively; whereas the similar reaction of 1 with[Ag(OTf)PPh3] affords chelate complex of the type [Ag{η2-Ph2P(-OC10H6)(μ-CH2)(C10H6O-)PPh2-κP,κP}(PPh3)(SO3CF3)] (10). All the complexes were characterized by 1H NMR, 31P NMR, elemental analysis and mass spectrometry, including low-temperature NMR studies in the case of silver complexes. The molecular structures of 4 and 6 are determined by X-ray diffraction studies. Ruthenium complexes 2 and 3 promote catalytic hydrogenation of styrene and phenylacetylene with good turnover numbers. 相似文献
957.
以烟酸(4-烯丙基-2-甲氧基)苯酯(L)为配体,在四氢呋喃/水体系中设计合成了银-双键配位的新型配合物[AgL(NO3)]n (1)。通过X-射线单晶衍射方法对L和1进行了表征,分析了其光谱及结构特征。结构分析表明,化合物L和1都为单斜晶系,配体L通过C-H…O氢弱作用依次形成二聚体、二维层结构。配合物1中,含有通过银-双键和氮原子配位的左旋曲绕链和通过银-氧弱作用形成的右旋曲绕链,两种链通过…ABAB…堆积形成二维结构,最后通过C-H…O弱作用形成三维结构。同时对化合物L和1的荧光性质进行了研究。 相似文献
958.
We report the use of silver (Ag)-modified carbon and Ag ultramicroelectrodes (UMEs) for electrochemical detection of nitrate. We investigated several methods for electrodeposition of Ag; our results show that the addition of a complexation agent (ammonium sulfate) in the Ag deposition solution is necessary for electrodeposition of nanostructured Ag that adheres well to the electrode. The electrodeposited Ag on both types of electrodes has branch-like structures that are well-suited for electrocatalytic reduction of nitrate. The use of UMEs is advantageous; the sigmoidal-shaped cyclic voltammogram allows for sensitive detection of nitrate by reducing the capacitive current, as well as enabling easy quantification of the nitrate reduction current. Both cyclic voltammetry and chronoamperometry were used to characterize the electrodes; and independent of the electrochemical interrogation technique, both UMEs were found to have a wide linear dynamic range (4–1000 μM) and a low limit of detection (3.2–5.1 μM). More importantly, they are reusable up to ∼100 interrogation cycles and are selective enough to be used for direct detection of nitrate in a synthetic aquifer sample without any sample pretreatment and/or pH adjustment. 相似文献
959.
Modeling of Structural,Energetic, and Dynamic Properties of Few‐Atom Silver Clusters Embedded in Polynucleotide Strands by Using Molecular Dynamics 下载免费PDF全文
Dr. Nicolas Staelens Dr. Laurence Leherte Prof. Benoît Champagne Prof. Daniel P. Vercauteren 《Chemphyschem》2015,16(2):360-369
This work concerns the study of the structural, energetic, and dynamic properties of fluorescent systems composed of silver clusters stabilized by polynucleotide strands. To do so, classical interaction potentials relative to silver, neutral and cationic, were introduced in the AMBER force field. Molecular dynamics simulations allowed analysis of the nature and force of the interactions between the various parts of the nucleic oligomers and the silver clusters. Conformational analyses were necessary to explore the flexibility of the supramolecular assemblies, specifically by radial distribution functions and Ramachandran‐type maps. 相似文献
960.
Zu‐Ping Xiao Meng Wen Chun‐Ya Wang Xi‐He Huang 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(4):258-261
The title compound, {[Ag(C6H7AsNO3)(C18H15P)]·H2O}n, has been synthesized from the reaction of 4‐aminophenylarsonic acid with silver nitrate, in aqueous ammonia, with the addition of triphenylphosphane (PPh3). The AgI centre is four‐coordinated by one amino N atom, one PPh3 P atom and two arsonate O atoms, forming a severely distorted [AgNPO2] tetrahedron. Two AgI‐centred tetrahedra are held together to produce a dinuclear [Ag2O2N2P2] unit by sharing an O–O edge. 4‐Aminophenylarsonate (Hapa−) adopts a μ3‐κ3N:O:O‐tridentate coordination mode connecting two dinuclear units, resulting in a neutral [Ag(Hapa)(PPh3)]n layer lying parallel to the (10) plane. The PPh3 ligands are suspended on both sides of the [Ag(Hapa)(PPh3)]n layer, displaying up and down orientations. There is an R22(8) hydrogen‐bonded dimer involving two arsonate groups from two Hapa− ligands related by a centre of inversion. Additionally, there are hydrogen‐bonding interactions involving the solvent water molecules and the arsonate and amine groups of the Hapa− ligands, and weak π–π stacking interactions within the [Ag(Hapa)(PPh3)]n layer. These two‐dimensional layers are further assembled by weak van der Waals interactions to form the final architecture. 相似文献