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101.
Synthesis and catalytic study of open metal site metal–organic frameworks of Cu3(BTC)2 microbelts in selective organic sulfide oxidation 下载免费PDF全文
The synthesis of open metal site metal–organic frameworks of Cu3(BTC)2 with microbelt morphology and a study of the catalytic oxidation of organic sulfides are reported. This CuBTC was found to be an efficient, selective and waste‐free green heterogeneous co‐catalyst for the green H2O2 catalytic oxidation of sulfides. The catalyst can be isolated from the reaction mixture and reused at least five times. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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A three-component domino reaction approach between a primary amine, a dialkyl acetylenedicarboxylate, and 1,3-dimethylalloxan that affords novel oxaspirobicyclic γ-butenolidobarbiturate derivatives is reported. The reaction sequence consists of an initial Michael-addition of primary amines to dialkyl acetylenedicarboxylates, followed by aldol-like reaction with 1,3-dimethylalloxan, and then γ-lactonization to afford the products. This cascade reaction sequence represents a rapid and unprecedented route to the described biologically interesting molecules. 相似文献
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Biuck Habibi Mohammad Hossien Pournaghi-Azar 《Journal of Solid State Electrochemistry》2010,14(4):599-613
Electrochemically platinum plated aluminum (Al/Pt) was used as an electrode substrate for the electropolymerization of aminophenols
and fabrication of composite electrodes based on platinum nano-particles. The poly(o-aminophenol) (PoAP), poly(m-aminophenol) (PmAP), and poly(p-aminophenol) (PpAP) were synthesized on the Al/Pt electrode, and further modification was performed by deposition of platinum nano-particles
onto polymer matrixes. The electrochemical and morphological characteristic of the composed electrodes were carried out by
cyclic voltammetry and scanning electron microscopy, respectively. The electrocatalytic oxidation of methanol on the composite
electrodes was studied by cyclic voltammetry in 0.1 M sulfuric acid as supporting electrolyte. It was found that the Al/Pt/PoAP electrode incorporated Pt nano-particles (Al/Pt/PoAP/Pt) exhibits a higher electrocatalytic activity for the oxidation of methanol than the Al/Pt/PmAP/Pt and Al/Pt/PpAP/Pt electrodes. On the other hand, a higher catalytic current for methanol oxidation was found on the Al/Pt/PoAP/Pt electrode in comparison to bulk Pt and Al–Pt (Al with 0.2 mg cm−2 of Pt particles) electrodes. The effects of various parameters such as thickness of the polymer film, concentration of the
monomer, Pt loading method and the Pt amounts, concentration of the methanol, and the medium temperature were studied on the
electrooxidation of methanol. The long-term stability of the modified electrode has also been investigated. 相似文献
107.
Zhao Yue Waqas Khalid Marco Zanella Azhar Zahoor Abbasi Andrea Pfreundt Pilar Rivera Gil Kirsten Schubert Fred Lisdat Wolfgang J. Parak 《Analytical and bioanalytical chemistry》2010,396(3):1095-1103
Gold electrodes with switchable conductance are created by coating the gold surface with different colloidal quantum dots.
For the quantum dot immobilization, a dithiol compound was used. By polarizing the electrode and applying a light pointer,
local photocurrents were generated. The performance of this setup was characterized for a variety of different nanoparticle
materials regarding drift and signal-to-noise ratio. We varied the following parameters: quantum dot materials and immobilization
protocol. The results indicate that the performance of the sensor strongly depends on how the quantum dots are bound to the
gold electrode. The best results were obtained by inclusion of an additional polyelectrolyte film, which had been fabricated
using layer-by-layer assembly.
相似文献
108.
S. Mahmood S.A. Abbasi S. Jabeen M.A. Baig 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(5):689-695
We present laser-induced breakdown spectroscopic studies of variety of marbles extracted from Quetta region of Boluchistan, Pakistan using a Nd:YAG laser (532 nm) in conjunction with LIBS 2000 detection system. The emission spectra of Onyx (white spot) and Quetta Green Marble samples have been recorded as a function of laser irradiance. The elemental composition and their relative abundance in each sample are fond to be quite different. In Onyx (white spot), calcium dominates while in the Quetta Green marble magnesium is the dominant element. In addition the effect of the laser irradiance on the emission intensity, width and shift of the transition lines have been studied. 相似文献
109.
A graph, G, is called uniquely Hamiltonian if it contains exactly one Hamilton cycle. We show that if G=(V, E) is uniquely Hamiltonian then
Where #(G)=1 if G has even number of vertices and 2 if G has odd number of vertices. It follows that every n-vertex uniquely Hamiltonian graph contains a vertex whose degree is at most c log2n+2 where c=(log23−1)−1≈1.71 thereby improving a bound given by Bondy and Jackson [3]. 相似文献
110.
Mehdi Ghandi Parham Asgari Abuzar Taheri Alireza Abbasi 《Central European Journal of Chemistry》2010,8(4):899-905
One-pot, three-component condensation of 2-hydroxybenzaldehyde derivatives, primary amines with alkyl isocyanides is reported.
N-alkyl-2-(2-hydroxyphenyl)-2-iminoacetamide derivatives are generated presumably via the preliminary formation of N, N′-disubstituted benzo[b]furan-2,3-diamines and subsequent oxidation with molecular oxygen.
相似文献