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11.
Dierk Knittel 《Monatshefte für Chemie / Chemical Monthly》1982,113(1):37-41
The reaction of the electrolytically generated SO
2
–
anion radical with 1,-dihalides is used for the synthesis of sulfur containing heterocycles like oxathiolane-, oxathiane-, thiane- and thiepane-oxides. 1,2-Dihalides are reductively deblocked to give olefines.
Kathodische Reduktion von SO2 in Gegenwart organischer Dihalogenide
Zusammenfassung Die Reaktion des elektrolytisch erzeugten SO 2 – -Anionradikals mit 1,-Dihalogeniden führt zu schwefelhaltigen Heterocyclen wie Oxathiolan-, Oxathian-, Thian- und Thiepanoxiden. 1,2-Dihalogenide geben durch reduktive Eliminierung Olefine.相似文献
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Fabian Gyger André Sackmann Michael Hübner Pascal Bockstaller Dagmar Gerthsen Henning Lichtenberg Jan‐Dierk Grunwaldt Nicolae Barsan Udo Weimar Claus Feldmann 《Particle & Particle Systems Characterization》2014,31(5):591-596
Pd@SnO2 and SnO2@Pd core@shell nanocomposites are prepared via a microemulsion approach. Both nanocomposites exhibit high‐surface, porous matrices of SnO2 shells (>150 m2 g?1) with very small SnO2 crystallites (<10 nm) and palladium (Pd) nanoparticles (<10 nm) that are uniformly distributed in the porous SnO2 matrix. Although similar by first sight, Pd@SnO2 and SnO2@Pd are significantly different in view of their structure with Pd inside or outside the SnO2 shell and in view of their sensor performance. As SMOX‐based sensors (SMOX: semiconducting metal oxide), both nanocomposites show a very good sensor performance for the detection of CO and H2. Especially, the Pd@SnO2 core@shell nanocomposite is unique and shows a fast response time (τ90 < 30 s) and a very good response at low temperature (<250 °C), especially under humid‐air conditions. Extraordinarily high sensor signals are observed when exposing the Pd@SnO2 nanocomposite to CO in humid air. Under these conditions, even commercial sensors (Figaro TGS 2442, Applied Sensor MLC, E2V MICS 5521) are outperformed. 相似文献
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Dr. Joohyun Lim Ghoncheh Kasiri Dr. Rajib Sahu Kevin Schweinar Dr. Katharina Hengge Prof. Dr. Dierk Raabe Prof. Dr. Fabio La Mantia Prof. Dr. Christina Scheu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(22):4917-4922
The structural changes of copper hexacyanoferrate (CuHCF), a Prussian blue analogue, which occur when used as a cathode in an aqueous Zn-ion battery, are investigated using electron microscopy techniques. The evolution of ZnxCu1−xHCF phases possessing wire and cubic morphologies from initial CuHCF nanoparticles are monitored after hundreds of cycles. Irreversible introduction of Zn ions to CuHCF is revealed locally using scanning transmission electron microscopy. A substitution mechanism is proposed to explain the increasing Zn content within the cathode material while simultaneously the Cu content is lowered during Zn-ion battery cycling. The present study demonstrates that the irreversible introduction of Zn ions is responsible for the decreasing Zn ion capacity of the CuHCF cathode in high electrolyte concentration. 相似文献
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Cathodic reduction of 2-azido-2,4-pentadien-1-ones under slightly protic conditions result in aminodienones, whereas under acetylating conditions only the methyl-N,N-diacetylaminoadienoates could be prepared in reasonable yields. The low reduction potential of the N,N-diacetylaminodienones leads to a mixture of by-products. The N,N-diacetylaminodienoates were studied as a model of the reduction of the azidodienes at higher reduction potentials. Dimerisation, reduction of the double-bonds and elimination of the N,N-diacetylamino group are possible reactions. The mechanism of reduction under acetylating conditions is discussed. 相似文献
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A new, sensitive assay for the quantitative determination of immobilized metal containing enzymes has been developed using atomic absorption spectroscopy (AAS). In contrast with conventionally used indirect methods the described quantitative AAS assay for metalloenzymes allows more exact analyses, because the carrier material with the enzyme is investigated directly. As an example, the validity and reliability of the method was examined by fixing the iron-containing enzyme catalase on cotton fabrics using different immobilization techniques. Sample preparation was carried out by dissolving the loaded fabrics in sulfuric acid before oxidising the residues with hydrogen peroxide. The iron concentrations were determined by flame atomic absorption spectrometry after calibration of the spectrometer with solutions of the free enzyme at different concentrations. 相似文献
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T. N. Mamedov D. G. Andrianov D. Herlach V. N. Gorelkin K. I. Gritsai V. N. Duginov O. Kormann J. Major A. V. Stoikov U. Zimmermann 《JETP Letters》2001,73(12):674-677
Results of studying the temperature dependence of the residual polarization of negative muons in crystalline silicon with germanium (9×10 19 cm ?3 ) and boron (4.1×10 18 , 1.34×10 19 , and 4.9×10 19 cm ?3 ) impurities are presented. It is found that, similarly to n-and p-type silicon samples with impurity concentrations up to ~10 17 cm ?3 , the relaxation rate ν of the magnetic moment of a μ Al acceptor in silicon with a high impurity concentration of germanium (9×10 19 cm ?3 ) depends on temperature as ν~T q , q≈3 at T=(5–30) K. An increase in the absolute value of the relaxation rate and a weakening of its temperature dependence are observed in samples of degenerate silicon in the given temperature range. Based on the experimental data obtained, the conclusion is made that the spin-exchange scattering of free charge carriers makes a significant contribution to the magnetic moment relaxation of a shallow acceptor center in degenerate silicon at T?30 K. Estimates are obtained for the effective cross section of the spin-exchange scattering of holes (σ h ) and electrons (σ e ) from an Al acceptor center in Si: σ h ~10?13 cm2 and σ e ~8×10?15 cm2 at the acceptor (donor) impurity concentration n a (n d )~4×1018 cm?3. 相似文献