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71.
O. A. Efremova Yu. V. Mironov N. V. Kuratieva V. E. Fedorov 《Russian Chemical Bulletin》2006,55(11):1946-1949
The reactions of the rhenium chalcocyanide cluster salts K4[Re4Q4(CN)12]·6H2O (Q = S or Se) with Cu2+ cations coordinated by the bidentate ligand 2,2′-bipyridyl (bipy) produced two new cluster compounds, [Cu(NH3)(bipy)2]2[Re4S4(CN)12]·bipy·3.25H2O (1) and [{Cu(bipy)2}2Re4Se4(CN)12]·bipy·8.5H2O (2). The structures of these complexes were solved by X-ray diffraction. Compound 1 is ionic. Compound 2 is molecular. In the structures of both compounds, there are staking interactions between the {Cu(bipy)2}2+ cationic moieties and the solvate 2,2′-bipyridyl molecules.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1875–1878, November, 2006. 相似文献
72.
Guangdong Zhou Zhanlin Xu Xiaohong Guo Hong Zhuang Yanan Li Xueju Lü Tiexin Cheng Wenxing Li Kaiji Zhen 《Reaction Kinetics and Catalysis Letters》2005,85(1):57-64
Summary The oxidation of hexanol in the presence of the Keggin-type heteropoly compounds (HPCs) H3PMonW12-nO40 (denoted as PMonW12-n, n=0,1) and Na5PW11ZO39 (denoted as PW11Z, Z = Mn, Fe, Co, Ni, Cu and Zn) was carried out to produce hexanal and hexanoic acid. The reaction was conducted in tert-butanol (t-BuOH), using cetylpyridinium bromide (CPB) salts of HPA and 15% aqueous H2O2 as oxidant under mild condition. The PMoW11 catalyst showed higher hexanol conversion of 25%, the lowest selectivity to hexanal of 64.4% and an efficient utilization of H2O2 of 34%. Over the transition metal substituted PW11Z catalysts decomposition of H2O2 was rapid. For these PW11Z catalysts, the efficient utilization of H2O2 decreased to 9% or even lower. By means of IR, UV-visible and GC-MS techniques the catalysts were characterized. 相似文献
73.
Poly(N‐vinyl‐2‐pyrrolidone‐crotonic acid) [P(VP/CrA)] hydrogels were prepared by irradiating the ternary mixture of VP/CrA and crosslinking agent ethylene glycol dimethacrylate (EGDMA) in water by γ rays at ambient temperature. Differential scanning calorimetry and thermogravimetric analysis were performed to evaluate the thermal properties of ionized networks and to establish if they showed thermal differences that could be related to the CrA content in the gel system. The volume swelling ratio of P(VP/CrA) hydrogels were investigated as a function of the pH in the immersing solution. The volume swelling ratio of these hydrogels increased with an increase in pH and a decrease CrA content in the hydrogel. The volume swelling ratio of the hydrogels was also evaluated using an equation, based on the Flory—Huggins thermodynamic theory, the phantom network theory of James–Guth and Donnan theory of swelling of weakly charged ionic gels for determination of the molecular weight between crosslinks and the polymer–solvent interaction parameter (χ). Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
74.
Robert Franzén 《高等学校化学研究》2006,22(5):602-605
IntroductionAqueous hydrogen peroxide is considered to be a“green”oxidant with a high oxidation efficiency due toits low molecular weight,cleanness in the oxidationprocess in which only harmless water is produced,lowcost of production and safe transport… 相似文献
75.
《Electroanalysis》2006,18(3):259-266
In this paper, a new strategy for constructing a mediator‐type amperometric hydrogen peroxide (H2O2) microbiosensor was described. An electropolymerized thionine film (PTH) was deposited directly onto a gold electrode surface. The resulting redox film was extremely thin, adhered well onto a substrate (electrode), and had a highly cross‐linked network structure. Consequently, horseradish peroxidase (HRP) was successfully immobilized on nanometer‐sized Au colloids, which were supported by thiol‐tailed groups of 11‐mercaptoundecanoic acid (11‐MUA) monolayer covalently bound onto PTH film. With the aid of the PTH mediator, HRP‐labeled Au colloids microbiosensor displayed excellent electrocatalytical response to the reduction of H2O2. This matrix showed a biocompatible microenvironment for retaining the native activity of the covalent HRP and a very low mass transport barrier to the substrate, which provided a fast amperometric response to H2O2. The proposed H2O2 microbiosensor exhibited linear range of 3.5 μM–0.7 mM with a detection limit of 0.05 μM (S/N=3). The response showed a Michaelis‐Menten behavior at larger H2O2 concentrations. The KMapp value for the biosensors based on 24 nm Au colloids was found to be 47 μM, which demonstrated that HRP immobilized on Au colloids exhibited a high affinity to H2O2 with no loss of enzymatic activity. This microbiosensor possessed good analytical performance and storage stability. 相似文献
76.
In this paper, the levels and the torsional microstates of hydrogen peroxide are determined from fully optimized ab initio calculations using a nuclear model in one dimension. Calculations have been performed at the MP2 level with the 6-311 G(2df,2pd), 6-31 1+G(2df,2pd), cc-pVTZ and AUG-cc-pVTZ basis sets including polarization orbitals and diffuse functions. The most stable conformation, calculated with the MP2/AUG-cc-pVTZ approach, is a trans–gauche conformer lying at 67.5° from the trans structure. By using the same level of calculations, the heights of the trans and cis barriers have been determined to be 386.5 and 2643.8 cm−1 in a good agreement with the experimental data. The variational torsional levels split into four components by the tunnelling effect of the barriers. The splitting of the fundamental level caused by the trans barrier has been found to be 11.8683 cm−1, whereas the splitting caused by the cis barrier is insignificant under n=2. Current ab initio energies confirm the experimental assignments and verify the separability of the torsion from the rest of the vibrations. However, the experimental relation of dependence on the torsion of the rotational constants cannot be reproduced in one-dimension and depends on several additional vibrational effects. 相似文献
77.
Xiaofei Han Run Liu Zhude Xu Weixiang Chen Yifan Zheng 《Electrochemistry communications》2005,7(12):1195-1198
Nanocrystalline cadmium peroxide thin film has been electrodeposited on indium doped tin oxide glass substrate from aqueous solution at room temperature. The grain size of the nanocrystals of the film is estimated from XRD and is about 14 nm. The deposits are decomposed at 228 °C by formation of CdO, releasing plentiful heat at same time. The band-gap of the nanocrystalline CdO film made from decomposition of electrodeposited CdO2 is around 2.4 eV. 相似文献
78.
A rapid flow-injection method with chemiluminescence (CL) detection is described for the determination of glutathione (GSH).
The method is based on the CL reaction of luminol and hydrogen peroxide. GSH can greatly enhance the chemiluminescence intensity
in 0.1 mol/L borax–sodium hydroxide buffer solution (pH = 9.7). The maximum CL intensity was directly proportional to the
concentration of GSH in the range 3.0 × 10−7–2.0 × 10−5 mol/L, and the detection limit was 6.8 × 10−8 mol/L. The relative standard deviation was 3.4% for 5.0 × 10−6 mol/L of GSH (n = 11).
Received October 23, 2001; accepted June 18, 2002 相似文献
79.
Catalytic oxidation of alcohols to carbonyl compounds with hydrogen peroxide using dinuclear iron complexes 总被引:2,自引:0,他引:2
Oxidation of primary and secondary alcohols has been studied in the presence of [Fe(ind)Cl]2O (1) and [Fe2(OMe)2(PAP)Cl4] (2) (indH = 1,3-bis(2′-pyridylimino)isoindoline; PAP = 1,4-di(2′-pyridyl)aminophthalazine) as catalysts using hydrogen peroxide as primary oxidant. The complexes were found to be suitable catalysts for the oxidation of alcohols to the corresponding carbonyl compounds in acetone as solvent. The reactivity of the alcohols is in the order primary < secondary < cyclic secondary < aromatic. The reaction mechanism in the case of 1 probable involves an iron-based oxidant, while in the case of 2 a free-radical mechanism is suggested. 相似文献
80.
Rong-Li Jia Zhong-Long Ma Cheng-Yang Wang Su-Mei Wang 《Reaction Kinetics and Catalysis Letters》2005,85(1):73-78
Summary Novel amorphous Ni-La-B/-Al2O3 catalysts have been developed for the production of hydrogen peroxide from carbon monoxide, water and oxygen. The experimental investigation confirmed that the catalyst dried at 120ºC in air shows the best initial activity. The deactivation of amorphous Ni-La-B/-Al2O3 catalysts was also studied. 相似文献