The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
R. Schlögl - One of the best experts on this subject based on the ideXlab platform.
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In situ UV‐VIS diffuse reflectance Spectroscopy of reduction–reoxidation of heteropoly compounds by methanol and ethanol: a correlation between spectroscopic and catalytic data
Catalysis Letters, 1999Co-Authors: J. Melsheimer, Sabri S. Mahmoud, G. Mestl, R. SchlöglAbstract:The degree of reduction/oxidation of H_4PVMo_11O_40 (HPA) and Cs_2H_2PVMo_11O_40 (CsPA) was studied during reduction and reoxidation by methanol, ethanol and mixtures with oxygen, respectively. The peak intensity of the intervalence charge transfer (IVCT) band, the apparent band gap energy (E _g ^* ) and catalytic data were obtained by in situ UV‐VIS diffuse reflectance spectrosccopy (UV‐VIS‐DRS) and on‐line gas chromatography (GC), respectively. The peak intensity of the IVCT band and E _g ^* increase during the reduction of heteropoly compounds by the alcohols. The spectroscopic and catalytic data (conversion, selectivity) correlate in the transient state during the reoxidation process. It is shown that isolated Keggin anions act as precursors for the active states of the catalysts, which molecular structure cannot be deduced from UV‐VIS Spectroscopy alone. UV‐VIS Spectroscopy, however, can serve as a tool to determine the degree of reduction in future combined in situ UV‐VIS/Raman/XRD studied.
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in situ uv vis diffuse reflectance Spectroscopy of reduction reoxidation of heteropoly compounds by methanol and ethanol a correlation between spectroscopic and catalytic data
Catalysis Letters, 1999Co-Authors: J. Melsheimer, Sabri S. Mahmoud, G. Mestl, R. SchlöglAbstract:The degree of reduction/oxidation of H4PVMo11O40 (HPA) and Cs2H2PVMo11O40 (CsPA) was studied during reduction and reoxidation by methanol, ethanol and mixtures with oxygen, respectively. The peak intensity of the intervalence charge transfer (IVCT) band, the apparent band gap energy (Eg*) and catalytic data were obtained by in situ UV‐VIS diffuse reflectance spectrosccopy (UV‐VIS‐DRS) and on‐line gas chromatography (GC), respectively. The peak intensity of the IVCT band and Eg* increase during the reduction of heteropoly compounds by the alcohols. The spectroscopic and catalytic data (conversion, selectivity) correlate in the transient state during the reoxidation process. It is shown that isolated Keggin anions act as precursors for the active states of the catalysts, which molecular structure cannot be deduced from UV‐VIS Spectroscopy alone. UV‐VIS Spectroscopy, however, can serve as a tool to determine the degree of reduction in future combined in situ UV‐VIS/Raman/XRD studied.
J. Melsheimer - One of the best experts on this subject based on the ideXlab platform.
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In situ UV‐VIS diffuse reflectance Spectroscopy of reduction–reoxidation of heteropoly compounds by methanol and ethanol: a correlation between spectroscopic and catalytic data
Catalysis Letters, 1999Co-Authors: J. Melsheimer, Sabri S. Mahmoud, G. Mestl, R. SchlöglAbstract:The degree of reduction/oxidation of H_4PVMo_11O_40 (HPA) and Cs_2H_2PVMo_11O_40 (CsPA) was studied during reduction and reoxidation by methanol, ethanol and mixtures with oxygen, respectively. The peak intensity of the intervalence charge transfer (IVCT) band, the apparent band gap energy (E _g ^* ) and catalytic data were obtained by in situ UV‐VIS diffuse reflectance spectrosccopy (UV‐VIS‐DRS) and on‐line gas chromatography (GC), respectively. The peak intensity of the IVCT band and E _g ^* increase during the reduction of heteropoly compounds by the alcohols. The spectroscopic and catalytic data (conversion, selectivity) correlate in the transient state during the reoxidation process. It is shown that isolated Keggin anions act as precursors for the active states of the catalysts, which molecular structure cannot be deduced from UV‐VIS Spectroscopy alone. UV‐VIS Spectroscopy, however, can serve as a tool to determine the degree of reduction in future combined in situ UV‐VIS/Raman/XRD studied.
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in situ uv vis diffuse reflectance Spectroscopy of reduction reoxidation of heteropoly compounds by methanol and ethanol a correlation between spectroscopic and catalytic data
Catalysis Letters, 1999Co-Authors: J. Melsheimer, Sabri S. Mahmoud, G. Mestl, R. SchlöglAbstract:The degree of reduction/oxidation of H4PVMo11O40 (HPA) and Cs2H2PVMo11O40 (CsPA) was studied during reduction and reoxidation by methanol, ethanol and mixtures with oxygen, respectively. The peak intensity of the intervalence charge transfer (IVCT) band, the apparent band gap energy (Eg*) and catalytic data were obtained by in situ UV‐VIS diffuse reflectance spectrosccopy (UV‐VIS‐DRS) and on‐line gas chromatography (GC), respectively. The peak intensity of the IVCT band and Eg* increase during the reduction of heteropoly compounds by the alcohols. The spectroscopic and catalytic data (conversion, selectivity) correlate in the transient state during the reoxidation process. It is shown that isolated Keggin anions act as precursors for the active states of the catalysts, which molecular structure cannot be deduced from UV‐VIS Spectroscopy alone. UV‐VIS Spectroscopy, however, can serve as a tool to determine the degree of reduction in future combined in situ UV‐VIS/Raman/XRD studied.
G. Mestl - One of the best experts on this subject based on the ideXlab platform.
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In situ UV‐VIS diffuse reflectance Spectroscopy of reduction–reoxidation of heteropoly compounds by methanol and ethanol: a correlation between spectroscopic and catalytic data
Catalysis Letters, 1999Co-Authors: J. Melsheimer, Sabri S. Mahmoud, G. Mestl, R. SchlöglAbstract:The degree of reduction/oxidation of H_4PVMo_11O_40 (HPA) and Cs_2H_2PVMo_11O_40 (CsPA) was studied during reduction and reoxidation by methanol, ethanol and mixtures with oxygen, respectively. The peak intensity of the intervalence charge transfer (IVCT) band, the apparent band gap energy (E _g ^* ) and catalytic data were obtained by in situ UV‐VIS diffuse reflectance spectrosccopy (UV‐VIS‐DRS) and on‐line gas chromatography (GC), respectively. The peak intensity of the IVCT band and E _g ^* increase during the reduction of heteropoly compounds by the alcohols. The spectroscopic and catalytic data (conversion, selectivity) correlate in the transient state during the reoxidation process. It is shown that isolated Keggin anions act as precursors for the active states of the catalysts, which molecular structure cannot be deduced from UV‐VIS Spectroscopy alone. UV‐VIS Spectroscopy, however, can serve as a tool to determine the degree of reduction in future combined in situ UV‐VIS/Raman/XRD studied.
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in situ uv vis diffuse reflectance Spectroscopy of reduction reoxidation of heteropoly compounds by methanol and ethanol a correlation between spectroscopic and catalytic data
Catalysis Letters, 1999Co-Authors: J. Melsheimer, Sabri S. Mahmoud, G. Mestl, R. SchlöglAbstract:The degree of reduction/oxidation of H4PVMo11O40 (HPA) and Cs2H2PVMo11O40 (CsPA) was studied during reduction and reoxidation by methanol, ethanol and mixtures with oxygen, respectively. The peak intensity of the intervalence charge transfer (IVCT) band, the apparent band gap energy (Eg*) and catalytic data were obtained by in situ UV‐VIS diffuse reflectance spectrosccopy (UV‐VIS‐DRS) and on‐line gas chromatography (GC), respectively. The peak intensity of the IVCT band and Eg* increase during the reduction of heteropoly compounds by the alcohols. The spectroscopic and catalytic data (conversion, selectivity) correlate in the transient state during the reoxidation process. It is shown that isolated Keggin anions act as precursors for the active states of the catalysts, which molecular structure cannot be deduced from UV‐VIS Spectroscopy alone. UV‐VIS Spectroscopy, however, can serve as a tool to determine the degree of reduction in future combined in situ UV‐VIS/Raman/XRD studied.
Sabri S. Mahmoud - One of the best experts on this subject based on the ideXlab platform.
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In situ UV‐VIS diffuse reflectance Spectroscopy of reduction–reoxidation of heteropoly compounds by methanol and ethanol: a correlation between spectroscopic and catalytic data
Catalysis Letters, 1999Co-Authors: J. Melsheimer, Sabri S. Mahmoud, G. Mestl, R. SchlöglAbstract:The degree of reduction/oxidation of H_4PVMo_11O_40 (HPA) and Cs_2H_2PVMo_11O_40 (CsPA) was studied during reduction and reoxidation by methanol, ethanol and mixtures with oxygen, respectively. The peak intensity of the intervalence charge transfer (IVCT) band, the apparent band gap energy (E _g ^* ) and catalytic data were obtained by in situ UV‐VIS diffuse reflectance spectrosccopy (UV‐VIS‐DRS) and on‐line gas chromatography (GC), respectively. The peak intensity of the IVCT band and E _g ^* increase during the reduction of heteropoly compounds by the alcohols. The spectroscopic and catalytic data (conversion, selectivity) correlate in the transient state during the reoxidation process. It is shown that isolated Keggin anions act as precursors for the active states of the catalysts, which molecular structure cannot be deduced from UV‐VIS Spectroscopy alone. UV‐VIS Spectroscopy, however, can serve as a tool to determine the degree of reduction in future combined in situ UV‐VIS/Raman/XRD studied.
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in situ uv vis diffuse reflectance Spectroscopy of reduction reoxidation of heteropoly compounds by methanol and ethanol a correlation between spectroscopic and catalytic data
Catalysis Letters, 1999Co-Authors: J. Melsheimer, Sabri S. Mahmoud, G. Mestl, R. SchlöglAbstract:The degree of reduction/oxidation of H4PVMo11O40 (HPA) and Cs2H2PVMo11O40 (CsPA) was studied during reduction and reoxidation by methanol, ethanol and mixtures with oxygen, respectively. The peak intensity of the intervalence charge transfer (IVCT) band, the apparent band gap energy (Eg*) and catalytic data were obtained by in situ UV‐VIS diffuse reflectance spectrosccopy (UV‐VIS‐DRS) and on‐line gas chromatography (GC), respectively. The peak intensity of the IVCT band and Eg* increase during the reduction of heteropoly compounds by the alcohols. The spectroscopic and catalytic data (conversion, selectivity) correlate in the transient state during the reoxidation process. It is shown that isolated Keggin anions act as precursors for the active states of the catalysts, which molecular structure cannot be deduced from UV‐VIS Spectroscopy alone. UV‐VIS Spectroscopy, however, can serve as a tool to determine the degree of reduction in future combined in situ UV‐VIS/Raman/XRD studied.
Chan Hin Kam - One of the best experts on this subject based on the ideXlab platform.
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Effects of titanium content on properties of sol-gel silica-titania films via organically modified silane precursors
Journal of Physics D: Applied Physics, 2001Co-Authors: Wenxiu Que, Y. L. Lam, Zhiqiang Sun, Y C Chan, Chan Hin KamAbstract:The effects of titanium content on the properties of silica-titania\nfilms by the sol-gel method using gamma -glycidoxypropyltrimethoxysilane\n(GLYMO), tetraethoxysilane (TEOS) and tetrapropylorthotitanate (TPOT) as\nthe starting materials have been investigated. Atomic force microscopy\n(AFM), ellipsometry, thermal gravimetric analysis (TGA), UV-visible\nSpectroscopy (UV-VIS), Fourier transform infrared (FT-IR) Spectroscopy,\nx-ray photoelectron Spectroscopy (XPS) and Raman Spectroscopy have been\nused to investigate the optical and structural properties of the films.\nThese results showed that crack-free and high transparency tin the\nvisible and near infrared range) silica-titania films with a thickness\nof 0.75 mum could be obtained by a single spin-coating process after a\nheat treatment at 500 degreesC. The hardness and Young's modulus of the\nfilms were also characterized by a nanoindenter and showed a linear\ndependence on the titanium content. Hardness as high as 9.0 GPa was\nachieved in a high titanium content film at a heat treatment temperature\nof 800 degreesC.
