Mixed alcohol is of great promise as octane improver in automotive fuel,and hopeful to replace the MTBE to reduce the environmental pollution,In this field,alkali-promted molybdenum-based catalysts have been given spe...Mixed alcohol is of great promise as octane improver in automotive fuel,and hopeful to replace the MTBE to reduce the environmental pollution,In this field,alkali-promted molybdenum-based catalysts have been given special interest because of their excellent sulfur-tolerance for synthesis of mixed alcohol from CO+H2,It was reported that the coblat is a favorable promoter for enhancing alcohol production,especially for improving the selectivity for C2+ alcohol[1-3],moreover,strong interaction between Con and Mo is in favor of mixed alcohol synthesis[4].Recently,we prpared a kind of K-Co-Mo ultrafine particles by sol-gel method and it shows much smaller particle size but higher activty and selectivity toward alcohol formation than the one prepared by conventional method[5],The aim of the present work is to research the micostructures of the Mo and Co species in the K-Co-Mo samples prepared by different method.展开更多
The inhomogeneity in a congrunet LiTaO3 crystal has been observed by transmission synchrotron topography.Many extraordinary regions exist in congruent LiTaO3 crystal and they often show diffraction intensity different...The inhomogeneity in a congrunet LiTaO3 crystal has been observed by transmission synchrotron topography.Many extraordinary regions exist in congruent LiTaO3 crystal and they often show diffraction intensity different from that of ordinary regions in synchrotron topographs.Differential thermal analysis indiates that the Curie temperature of the extraordinary region is lower than that of ordinary region,and the extraordinary region is really a high defect density region.The diffraction contrast of the extraordinary region in synchrotron topographs is explained qualitatively by a calculation at the selected wavelength.2001 Published by Elsevier Science B.V.展开更多
文摘Mixed alcohol is of great promise as octane improver in automotive fuel,and hopeful to replace the MTBE to reduce the environmental pollution,In this field,alkali-promted molybdenum-based catalysts have been given special interest because of their excellent sulfur-tolerance for synthesis of mixed alcohol from CO+H2,It was reported that the coblat is a favorable promoter for enhancing alcohol production,especially for improving the selectivity for C2+ alcohol[1-3],moreover,strong interaction between Con and Mo is in favor of mixed alcohol synthesis[4].Recently,we prpared a kind of K-Co-Mo ultrafine particles by sol-gel method and it shows much smaller particle size but higher activty and selectivity toward alcohol formation than the one prepared by conventional method[5],The aim of the present work is to research the micostructures of the Mo and Co species in the K-Co-Mo samples prepared by different method.
文摘The inhomogeneity in a congrunet LiTaO3 crystal has been observed by transmission synchrotron topography.Many extraordinary regions exist in congruent LiTaO3 crystal and they often show diffraction intensity different from that of ordinary regions in synchrotron topographs.Differential thermal analysis indiates that the Curie temperature of the extraordinary region is lower than that of ordinary region,and the extraordinary region is really a high defect density region.The diffraction contrast of the extraordinary region in synchrotron topographs is explained qualitatively by a calculation at the selected wavelength.2001 Published by Elsevier Science B.V.