变频空调控制器核心器件IPM(Intelligent Power Module即智能功率模块),不仅把功率开关器件和驱动电路集成在一起。而且其内部还集成有过电压,过电流和过热等故障检测电路,并可将检测信号送到CPU。它由高速低功耗的管芯和优化的门极驱...变频空调控制器核心器件IPM(Intelligent Power Module即智能功率模块),不仅把功率开关器件和驱动电路集成在一起。而且其内部还集成有过电压,过电流和过热等故障检测电路,并可将检测信号送到CPU。它由高速低功耗的管芯和优化的门极驱动电路以及快速保护电路构成。即使发生负载事故或使用不当,也可以保证IPM自身不受损坏。IPM一般使用IGBT作为功率开关元件,内部集成电流传感器及驱动电路的集成结构。IPM以其高可靠性,使用方便赢得越来越大的市场,尤其适合于驱动电机的变频器和各种逆变电源,是变频调速,冶金机械,电力牵引,伺服驱动,变频家电的一种非常理想的电力电子器件,应用层面对其功率测试与技术研究报告分析。展开更多
[Objective] The aim of the study was to make research on adsorption of Chinese walnut(Juglans mandshurica Maxim.) Shell(CWS) to Hg(Ⅱ) in water.[Method] Shells of Juglans mandshurica Maxim were used as biosorpti...[Objective] The aim of the study was to make research on adsorption of Chinese walnut(Juglans mandshurica Maxim.) Shell(CWS) to Hg(Ⅱ) in water.[Method] Shells of Juglans mandshurica Maxim were used as biosorption to remove Hg(Ⅱ) in water solution to explore the influence to adsorption of Hg(Ⅱ) under different conditions,like pH solution,adsorption time,and Hg(Ⅱ).[Result] The experimental results show that when absorptivity of Hg(Ⅱ) by CWS reached the highest,pH ranged within 5.0-6.0.The adsorptivity decreased as initial Hg(Ⅱ) concentrations increased.Fourier Transform Infrared Spectroscopy(FTIR) spectrum revealed some chemical groups of CWS may affect the adsorption of Hg(Ⅱ),such as hydroxyl groups,methyl groups,aromatic methoxyl groups,unconjugated carbonyl,and typical aromatic ring,etc.Adsorption equation can be concluded considering the biosorption process relationship with Langmuir and Frendrich isotherm.[Conclusion] The study found that CW could be employed as a promising biosorption to remove Hg(Ⅱ) from aqueous environments.展开更多
[Objective] The aim was to study the preservation of fresh Chinese wolfberry fruit via chitosan coating. [Method] Using Chinese wolfberry "Ningqi No. 1" as experimental material, the fresh fruits were coated...[Objective] The aim was to study the preservation of fresh Chinese wolfberry fruit via chitosan coating. [Method] Using Chinese wolfberry "Ningqi No. 1" as experimental material, the fresh fruits were coated by different concentrations of chitosan(0.75%, 1.00%, 1.25%, 1.50% and 1.75%) at room temperature to study the changes in weight loss rate, rate of rotten fruits rot, soluble solid content and vitamin C(Vc) content. [Result] Of all the treatments, the fruits coated with 1.25% chitosan showed lowest rate of rotten fruit and weight loss rate, and highest Vc and soluble solid content, presenting the optimal fresh-keeping effect. [Conclusion] Chitosan coating is helpful for the preservation of fresh Chinese wolfberry fruit at room temperature.展开更多
文摘变频空调控制器核心器件IPM(Intelligent Power Module即智能功率模块),不仅把功率开关器件和驱动电路集成在一起。而且其内部还集成有过电压,过电流和过热等故障检测电路,并可将检测信号送到CPU。它由高速低功耗的管芯和优化的门极驱动电路以及快速保护电路构成。即使发生负载事故或使用不当,也可以保证IPM自身不受损坏。IPM一般使用IGBT作为功率开关元件,内部集成电流传感器及驱动电路的集成结构。IPM以其高可靠性,使用方便赢得越来越大的市场,尤其适合于驱动电机的变频器和各种逆变电源,是变频调速,冶金机械,电力牵引,伺服驱动,变频家电的一种非常理想的电力电子器件,应用层面对其功率测试与技术研究报告分析。
基金Supported by National Water Major Project of China (2008ZX07211-007)~~
文摘[Objective] The aim of the study was to make research on adsorption of Chinese walnut(Juglans mandshurica Maxim.) Shell(CWS) to Hg(Ⅱ) in water.[Method] Shells of Juglans mandshurica Maxim were used as biosorption to remove Hg(Ⅱ) in water solution to explore the influence to adsorption of Hg(Ⅱ) under different conditions,like pH solution,adsorption time,and Hg(Ⅱ).[Result] The experimental results show that when absorptivity of Hg(Ⅱ) by CWS reached the highest,pH ranged within 5.0-6.0.The adsorptivity decreased as initial Hg(Ⅱ) concentrations increased.Fourier Transform Infrared Spectroscopy(FTIR) spectrum revealed some chemical groups of CWS may affect the adsorption of Hg(Ⅱ),such as hydroxyl groups,methyl groups,aromatic methoxyl groups,unconjugated carbonyl,and typical aromatic ring,etc.Adsorption equation can be concluded considering the biosorption process relationship with Langmuir and Frendrich isotherm.[Conclusion] The study found that CW could be employed as a promising biosorption to remove Hg(Ⅱ) from aqueous environments.
基金Supported by the Scientific and Technological Project of Yinchuan City, Ningxia Province~~
文摘[Objective] The aim was to study the preservation of fresh Chinese wolfberry fruit via chitosan coating. [Method] Using Chinese wolfberry "Ningqi No. 1" as experimental material, the fresh fruits were coated by different concentrations of chitosan(0.75%, 1.00%, 1.25%, 1.50% and 1.75%) at room temperature to study the changes in weight loss rate, rate of rotten fruits rot, soluble solid content and vitamin C(Vc) content. [Result] Of all the treatments, the fruits coated with 1.25% chitosan showed lowest rate of rotten fruit and weight loss rate, and highest Vc and soluble solid content, presenting the optimal fresh-keeping effect. [Conclusion] Chitosan coating is helpful for the preservation of fresh Chinese wolfberry fruit at room temperature.