A new solid acid catalyst,SO4^2-/TiO2 modified with tin,was prepared using a sol-gel method and its physicochemical properties were revealed by nitrogen adsorption-desorption,X-ray powder diffraction,scanning electron...A new solid acid catalyst,SO4^2-/TiO2 modified with tin,was prepared using a sol-gel method and its physicochemical properties were revealed by nitrogen adsorption-desorption,X-ray powder diffraction,scanning electron microscopy,Fourier transform infrared spectroscopy,infrared spectroscopy of adsorbed pyridine,temperature-programmed desorption of ammonia and thermal gravimetric analysis.The structure,acidity and thermal stability of the SO4^2-/TiO2-SnO2 catalyst were studied.Incorporating tin enlarged the specific surface area and decreased crystallite size of the SO4^2-/TiO2 catalyst.The total acid sites of the modified catalyst increased and Bronsted acid strength remarkably increased with increasing tin content.The decomposition temperature of sulfate radical in the modified catalyst was 100 ℃ greater and its mass loss was more than twice that of the SO4^2-/TiO2 catalyst.The SO4^2-/TiO2-SnO2 catalyst was designed to synthesize 1,6-hexanediol diacrylate by esterification of 1,6-hexanediol with crylic acid.The yield of 1,6-hexanediol diacrylate exceeded 87% under the optimal reaction conditions：crylic acid to 1,6-hexanediol molar ratio = 3.5,catalyst loading = 7%,reaction temperature = 130 ℃ and reaction time = 3 h.The modified catalyst exhibited excellent reusability and after 10 cycles the conversion of 1,6-hexanediol was above 81%.展开更多
随着智能电网的快速发展与物联网终端设备的规模化应用部署,互联网协议第6版(Internet Protocol Version 6,IPv6)技术依托其丰富的地址资源和安全特性,已成为网络架构的关键支撑,IPv6地址的管理和日志审计对保障电网安全稳定运行至关重...随着智能电网的快速发展与物联网终端设备的规模化应用部署,互联网协议第6版(Internet Protocol Version 6,IPv6)技术依托其丰富的地址资源和安全特性,已成为网络架构的关键支撑,IPv6地址的管理和日志审计对保障电网安全稳定运行至关重要。系统探讨了智能电网中物联网设备IPv6地址相关技术原理,深入分析了IPv6地址日志审计技术在智能电网中的应用难点与挑战,提出一种IPv6地址日志审计的简易优化方案,并通过实际案例进行分析和可行性验证,为智能电网中的实际应用提供理论依据和实践指导,对推动智能电网网络安全建设具有重要意义。展开更多
文摘A new solid acid catalyst,SO4^2-/TiO2 modified with tin,was prepared using a sol-gel method and its physicochemical properties were revealed by nitrogen adsorption-desorption,X-ray powder diffraction,scanning electron microscopy,Fourier transform infrared spectroscopy,infrared spectroscopy of adsorbed pyridine,temperature-programmed desorption of ammonia and thermal gravimetric analysis.The structure,acidity and thermal stability of the SO4^2-/TiO2-SnO2 catalyst were studied.Incorporating tin enlarged the specific surface area and decreased crystallite size of the SO4^2-/TiO2 catalyst.The total acid sites of the modified catalyst increased and Bronsted acid strength remarkably increased with increasing tin content.The decomposition temperature of sulfate radical in the modified catalyst was 100 ℃ greater and its mass loss was more than twice that of the SO4^2-/TiO2 catalyst.The SO4^2-/TiO2-SnO2 catalyst was designed to synthesize 1,6-hexanediol diacrylate by esterification of 1,6-hexanediol with crylic acid.The yield of 1,6-hexanediol diacrylate exceeded 87% under the optimal reaction conditions：crylic acid to 1,6-hexanediol molar ratio = 3.5,catalyst loading = 7%,reaction temperature = 130 ℃ and reaction time = 3 h.The modified catalyst exhibited excellent reusability and after 10 cycles the conversion of 1,6-hexanediol was above 81%.
文摘随着智能电网的快速发展与物联网终端设备的规模化应用部署,互联网协议第6版(Internet Protocol Version 6,IPv6)技术依托其丰富的地址资源和安全特性,已成为网络架构的关键支撑,IPv6地址的管理和日志审计对保障电网安全稳定运行至关重要。系统探讨了智能电网中物联网设备IPv6地址相关技术原理,深入分析了IPv6地址日志审计技术在智能电网中的应用难点与挑战,提出一种IPv6地址日志审计的简易优化方案,并通过实际案例进行分析和可行性验证,为智能电网中的实际应用提供理论依据和实践指导,对推动智能电网网络安全建设具有重要意义。
