This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hy...This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hydroxide-carbonate nanoparticles with various morphologies（i.e.,nanorods,nanosheets,and nanocubes） were successfully synthesized,and Co3O4 nanoparticles were obtained by thermal decomposition of the cobalt-hydroxide-carbonate precursors.The results suggest that the cobalt source is a key factor for controlling the morphology of cobalt-hydroxide-carbonate at relatively low hydrothermal temperatures（≤ 140℃）.Nanorods can be synthesized in CoCl2 solution,while Co（NO3）2 solution promotes the formation of nanosheets.Further increasing the synthesis temperature（higher than 140 ℃） results in the formation of nanocubes in either Co（NO3）2 or CoCl2 solution.The reaction time only affects the size of the obtained nanoparticles.The presence of CTAB could improve the uniformity and dispersion of particles.Co3O4 nanosheets showed much higher catalytic activity for CO oxidation than nanorods and nanocubes because it has more abundant Co^（3＋） on the surface,much higher reducibility,and better oxygen desorption capacity.展开更多
Based on the principle that the adaptation can be reflected by the overlap of reflectance distribution peaks,the effect of various types mixed coal for coking is analyzed.Based on the action of the vitrinite of differ...Based on the principle that the adaptation can be reflected by the overlap of reflectance distribution peaks,the effect of various types mixed coal for coking is analyzed.Based on the action of the vitrinite of different reflectance range and the adaptation,a new method for guidance blending coal is established.Through simulation,blending coal using the software of HD automatic microscope photometer,makes the synthetic blending coal reflectance distribution map to nothing notch wide single peak flat-shaped symmetrical distribution,blending coal random reflectance meets 1.1 - 1.2,the standard deviation meets 0.35 - 0.4.It is based on the conditions that active component in the blending is excessive.Using this method,the mixed coal can be used as much as possible and play a positive role.The problem about implementation process is discussed.展开更多
基金supported by the National Natural Science Foundation of China (51374004,51204083)the Candidate Talents Training Fund of Yun-nan Province (2012HB009,2014HB006)+2 种基金the Applied Basic Research Program of Yunnan Province (2014FB123)a School-Enterprise Cooperation Project from Jinchuan Corporation (Jinchuan 201115)the Talents Training Program of Kunming University of Science and Technology (KKZ3201352038)~~
文摘This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hydroxide-carbonate nanoparticles with various morphologies（i.e.,nanorods,nanosheets,and nanocubes） were successfully synthesized,and Co3O4 nanoparticles were obtained by thermal decomposition of the cobalt-hydroxide-carbonate precursors.The results suggest that the cobalt source is a key factor for controlling the morphology of cobalt-hydroxide-carbonate at relatively low hydrothermal temperatures（≤ 140℃）.Nanorods can be synthesized in CoCl2 solution,while Co（NO3）2 solution promotes the formation of nanosheets.Further increasing the synthesis temperature（higher than 140 ℃） results in the formation of nanocubes in either Co（NO3）2 or CoCl2 solution.The reaction time only affects the size of the obtained nanoparticles.The presence of CTAB could improve the uniformity and dispersion of particles.Co3O4 nanosheets showed much higher catalytic activity for CO oxidation than nanorods and nanocubes because it has more abundant Co^（3＋） on the surface,much higher reducibility,and better oxygen desorption capacity.
文摘Based on the principle that the adaptation can be reflected by the overlap of reflectance distribution peaks,the effect of various types mixed coal for coking is analyzed.Based on the action of the vitrinite of different reflectance range and the adaptation,a new method for guidance blending coal is established.Through simulation,blending coal using the software of HD automatic microscope photometer,makes the synthetic blending coal reflectance distribution map to nothing notch wide single peak flat-shaped symmetrical distribution,blending coal random reflectance meets 1.1 - 1.2,the standard deviation meets 0.35 - 0.4.It is based on the conditions that active component in the blending is excessive.Using this method,the mixed coal can be used as much as possible and play a positive role.The problem about implementation process is discussed.
