Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-...Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-p)v, and the fractal dimension of the structure of dielectric breakdown df were obtained. Conclusion The breakdown properties of the materials with quenched disorder are characterized by universal power laws, where the exponents are universal.展开更多
A facile and efficient method has been developed for microencapsulation of metal oxide nanoparticles in polyurea via interfacial polymerization of toluene-2,4-diisocyanate and H20 through the atomizing emulsification ...A facile and efficient method has been developed for microencapsulation of metal oxide nanoparticles in polyurea via interfacial polymerization of toluene-2,4-diisocyanate and H20 through the atomizing emulsification approach. The resultant microcapsules were well-shaped and uniform sphere with diameter ranging from 2 to 6 um. Thermogravimetry （TG） and differential scanning calorimetry （DSC） curves revealed that the microcapsules showed good thermal stability （no decomposition observed under 245℃）. Besides, the microencapsulated TiC2 has been used as an efficient catalyst for photocatalytic degradation of methyl orange. Furthermore, the photocatalysis of immobilized TiC2 could be enhanced by introducing UV absorbing agent to the wall of microcapsules.展开更多
文摘Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-p)v, and the fractal dimension of the structure of dielectric breakdown df were obtained. Conclusion The breakdown properties of the materials with quenched disorder are characterized by universal power laws, where the exponents are universal.
基金Supported by the National Natural Science Foundation of China （20576045） and the Program for New Century Excellent Talents in University （NCET-06-740）.
文摘A facile and efficient method has been developed for microencapsulation of metal oxide nanoparticles in polyurea via interfacial polymerization of toluene-2,4-diisocyanate and H20 through the atomizing emulsification approach. The resultant microcapsules were well-shaped and uniform sphere with diameter ranging from 2 to 6 um. Thermogravimetry （TG） and differential scanning calorimetry （DSC） curves revealed that the microcapsules showed good thermal stability （no decomposition observed under 245℃）. Besides, the microencapsulated TiC2 has been used as an efficient catalyst for photocatalytic degradation of methyl orange. Furthermore, the photocatalysis of immobilized TiC2 could be enhanced by introducing UV absorbing agent to the wall of microcapsules.
