In this paper, 2-isopropyl naphthalene has been synthesized by the reaction of naphthalene and isopropyl bromide, using triethylamine hydrochloride-aluminum chloride ionic liquid as the catalyst. The effect of the cat...In this paper, 2-isopropyl naphthalene has been synthesized by the reaction of naphthalene and isopropyl bromide, using triethylamine hydrochloride-aluminum chloride ionic liquid as the catalyst. The effect of the catalyst composition, the reaction time, the reaction temperature, the ionic liquid dosage, as well as the molar ratio of the reagents on the 2-isopropyl naphthalene yield was systematically investigated. The optimal reaction conditions cover: an AlCl3 to Et3NHCl ratio of 2.0, a reaction time of 3 h, a reaction temperature of 15.0 ℃, a volume fraction of ionic liquid to the mixture(isopropyl bromide, n-dodecane and n-hexane) of 9%, and a naphthalene/isopropyl bromide molar ratio of 4.0. Under the optimal reaction conditions, the conversion of isopropyl bromide reached 98% and the selectivity of 2-isopropyl naphthalene was equal to 80%. The test results verified good catalytic activity upon using Et3NHCl-AlCl3 ionic liquid as the catalyst for alkylation of naphthalene with isopropyl bromide. The activity of the ionic liquid remains unchanged after it has been recycled for 4 times.展开更多
SiC MOSFET凭借着低开关损耗、高工作频率与高工作温度点等优点,逐渐在高效率、高功率密度与高温的应用场合取代传统的硅功率器件。然而,在高速开关中带来的栅极串扰现象严重制约SiC器件的开关速度。传统的串扰抑制方法重点关注由栅极...SiC MOSFET凭借着低开关损耗、高工作频率与高工作温度点等优点,逐渐在高效率、高功率密度与高温的应用场合取代传统的硅功率器件。然而,在高速开关中带来的栅极串扰现象严重制约SiC器件的开关速度。传统的串扰抑制方法重点关注由栅极–漏极寄生电容引入的干扰电压,往往通过减小驱动回路阻抗的方式来降低串扰电压。该文基于SiC MOSFET器件的开关模态,提出考虑共源电感的分段线性化串扰电压模型。该模型基于器件数据手册及双脉冲实验提取的参数,考虑栅极–漏极电容、共源电感、体二极管反向恢复等非理想因素的影响。对比不同电压点、电流点与电阻值下实验与模型的输出结果。该模型表明,串扰电压是由器件栅极–漏极电容、共源电感与驱动回路阻抗共同作用的结果。单一降低驱动回路阻抗的方式对串扰电压的抑制效果有限。基于提出的模型,该文给出串扰电压抑制的指导方法,可直接用于SiC MOSFET驱动电路的设计。展开更多
基金financially supported by the National Natural Science Foundation of China (No. 21205086)
文摘In this paper, 2-isopropyl naphthalene has been synthesized by the reaction of naphthalene and isopropyl bromide, using triethylamine hydrochloride-aluminum chloride ionic liquid as the catalyst. The effect of the catalyst composition, the reaction time, the reaction temperature, the ionic liquid dosage, as well as the molar ratio of the reagents on the 2-isopropyl naphthalene yield was systematically investigated. The optimal reaction conditions cover: an AlCl3 to Et3NHCl ratio of 2.0, a reaction time of 3 h, a reaction temperature of 15.0 ℃, a volume fraction of ionic liquid to the mixture(isopropyl bromide, n-dodecane and n-hexane) of 9%, and a naphthalene/isopropyl bromide molar ratio of 4.0. Under the optimal reaction conditions, the conversion of isopropyl bromide reached 98% and the selectivity of 2-isopropyl naphthalene was equal to 80%. The test results verified good catalytic activity upon using Et3NHCl-AlCl3 ionic liquid as the catalyst for alkylation of naphthalene with isopropyl bromide. The activity of the ionic liquid remains unchanged after it has been recycled for 4 times.
