Results 231 to 240 of about 225,991 (262)
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Journal of Molecular Catalysis A: Chemical, 2001
Abstract Theoretical studies on ethene metathesis reaction proceeding on molybdenamethylidene centres of molybdena-alumina catalyst are reported. Calculations were carried out with the Gaussian 94 program, using density functional theory. Models of active sites containing MoVI and MoIV (both singlet and triplet state) have been developed.
Jarosław Handzlik, Jan Ogonowski
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Abstract Theoretical studies on ethene metathesis reaction proceeding on molybdenamethylidene centres of molybdena-alumina catalyst are reported. Calculations were carried out with the Gaussian 94 program, using density functional theory. Models of active sites containing MoVI and MoIV (both singlet and triplet state) have been developed.
Jarosław Handzlik, Jan Ogonowski
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Ageing and Society, 2014
ABSTRACTResearch on minority ethnic ageing remains a neglected area within mainstream race and ethnicity studies as well as that of social gerontology. This paper examines the background and reasons for this, arguing that a focus on minority ethnic issues provides a reminder of the complexity of the lifecourse, and of the diversity of ageing as a ...
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ABSTRACTResearch on minority ethnic ageing remains a neglected area within mainstream race and ethnicity studies as well as that of social gerontology. This paper examines the background and reasons for this, arguing that a focus on minority ethnic issues provides a reminder of the complexity of the lifecourse, and of the diversity of ageing as a ...
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The European Physical Journal D, 2014
Local structure and electron paramagnetic resonance (EPR) parameters (the g factors, g i , and the hyperfine structure constants A i , i = x, y, z) for the impurity Cu2+ centres in a (CH3)2NH2Al(SO4)2·6H2O (DMAAS) crystal are theoretically investigated ...
Hua-Ming Zhang, Wen-Bo Xiao, Xiong Wan
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Local structure and electron paramagnetic resonance (EPR) parameters (the g factors, g i , and the hyperfine structure constants A i , i = x, y, z) for the impurity Cu2+ centres in a (CH3)2NH2Al(SO4)2·6H2O (DMAAS) crystal are theoretically investigated ...
Hua-Ming Zhang, Wen-Bo Xiao, Xiong Wan
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Journal of Physics and Chemistry of Solids, 2015
Abstract The dependence of the EPR g-factors on the local structural parameter for a 4f11 configuration ion Er3+ in a trigonal crystal-field has been studied by diagonalizing the 364×364 complete energy matrices. Our studies indicate that the EPR spectra of the trigonal Er3+–VK centers in KMgF3 and KZnF3 may be attributed to the translation of the ...
Rui-Peng Chai +3 more
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Abstract The dependence of the EPR g-factors on the local structural parameter for a 4f11 configuration ion Er3+ in a trigonal crystal-field has been studied by diagonalizing the 364×364 complete energy matrices. Our studies indicate that the EPR spectra of the trigonal Er3+–VK centers in KMgF3 and KZnF3 may be attributed to the translation of the ...
Rui-Peng Chai +3 more
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Free Radical Research, 2019
Radiation chemical studies of thioesculetin (1), a thioketone derivative of coumarin, were performed by both pulse radiolysis technique and DFT calculations. Hydroxyl (•OH) radical reaction with 1 resulted transients absorbing at 320, 360 and 500 nm. To identify the nature of the transients, the reaction was studied with specific one-electron oxidant ...
Rupali G. Shinde +2 more
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Radiation chemical studies of thioesculetin (1), a thioketone derivative of coumarin, were performed by both pulse radiolysis technique and DFT calculations. Hydroxyl (•OH) radical reaction with 1 resulted transients absorbing at 320, 360 and 500 nm. To identify the nature of the transients, the reaction was studied with specific one-electron oxidant ...
Rupali G. Shinde +2 more
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Optics Communications, 1999
Abstract Temperature dependencies of the total effective trap density N eff were studied theoretically for two-centre and three-charge-state photorefractive crystals. The results show that N eff usually decreases with increasing temperature in three-charge-state crystals, while it shows more complicated behaviour in two-centre crystals.
Mingjun Chi, S.X Dou, Peixian Ye
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Abstract Temperature dependencies of the total effective trap density N eff were studied theoretically for two-centre and three-charge-state photorefractive crystals. The results show that N eff usually decreases with increasing temperature in three-charge-state crystals, while it shows more complicated behaviour in two-centre crystals.
Mingjun Chi, S.X Dou, Peixian Ye
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Theoretical studies and structural analysis of models of surface organometallic centres [PDF]
, 2000 Theoretical calculations utilizing the density functional theory (DFT) method are presented here from the point of view of their applicability in modelling catalytic rhodium gem dicarbonyl, Rh(CO)2, species on silica surface. The surface rhodium gem dicarbonyls were modelled by [Rh(CO)2(OSiH3)], [Rh(CO)2(OHSiH3)]+, [Rh(CO)2(ClSiH3)]+, [Rh(CO)2(Cl ...
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Journal of Physics B: Atomic, Molecular and Optical Physics, 1994
State-to-state rotational transitions of planar structures forming regular polygons are studied within a simple spectator model, which for electron-diatomic molecule scattering has been found to be in excellent agreement with experiments. Selection rules in the state-to-state transition probabilities for the excitation from the ground state are ...
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State-to-state rotational transitions of planar structures forming regular polygons are studied within a simple spectator model, which for electron-diatomic molecule scattering has been found to be in excellent agreement with experiments. Selection rules in the state-to-state transition probabilities for the excitation from the ground state are ...
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IETE Journal of Research, 1975
Theoretical study of the centre fed non-planar diode antenna with transversely displaced feed points in plasma medium is presented. Mathematical expressions for the radiation patterns are developed and calculations are made to predict the effect of feed points displacement on the radiation patterns of the centre fed half-wave and full-wave non-planar ...
Prem Swarup Bhatnagar, P. K. Chaturvedi
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Theoretical study of the centre fed non-planar diode antenna with transversely displaced feed points in plasma medium is presented. Mathematical expressions for the radiation patterns are developed and calculations are made to predict the effect of feed points displacement on the radiation patterns of the centre fed half-wave and full-wave non-planar ...
Prem Swarup Bhatnagar, P. K. Chaturvedi
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Molecular Physics, 2008
A theoretical method for investigating the inter-relation between the EPR parameters and local structure has been established on the basis of the complete energy matrices for 3d3 configuration ions in both the trigonal and tetragonal ligand fields. By means of this method, the local structure of the octahedral Cr3+ centres in double molybdates series ...
Rui-Peng Chai +4 more
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A theoretical method for investigating the inter-relation between the EPR parameters and local structure has been established on the basis of the complete energy matrices for 3d3 configuration ions in both the trigonal and tetragonal ligand fields. By means of this method, the local structure of the octahedral Cr3+ centres in double molybdates series ...
Rui-Peng Chai +4 more
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