N-dodecanethiol capped zinc sulfide（Zn S） nanocrystals were synthesized by the one-pot approach and blended with poly（N-vinylcarbazole）（PVK） to fabricate electrical bistable devices. The corresponding devices di...N-dodecanethiol capped zinc sulfide（Zn S） nanocrystals were synthesized by the one-pot approach and blended with poly（N-vinylcarbazole）（PVK） to fabricate electrical bistable devices. The corresponding devices did exhibit electrical bistability and negative differential resistance（NDR） effects. A large ON/OFF current ratio of 104 at negative voltages was obtained by applying different amplitudes of sweeping voltage. The observed conductance switching and the negative differential resistance are attributed to the electric-field-induced charge transfer between the nanocrystals and the polymer,and the charge trapping/detrapping in the nanocrystals.展开更多
以海洋温差能发电(Ocean Thermal Energy Conversion,OTEC)平台的冷水管为研究对象,根据结构方程和尾流振子方程建立冷水管流固耦合模型,采用有限元方法和Newmark-β法对冷水管涡激振动(Vortex-Induced Vibration,VIV)进行时域分析,并在...以海洋温差能发电(Ocean Thermal Energy Conversion,OTEC)平台的冷水管为研究对象,根据结构方程和尾流振子方程建立冷水管流固耦合模型,采用有限元方法和Newmark-β法对冷水管涡激振动(Vortex-Induced Vibration,VIV)进行时域分析,并在MATLAB软件中开发相应的求解程序。针对冷水管所面临的复杂工况,分别研究外部流场、内部流场、长径比和压载质量等因素对VIV产生的影响。结果表明:随着外流流速和长径比的增大,冷水管横流向VIV模态和振动幅值也发生相应改变,振动强度呈现波动上升;在不发生动态失稳的情况下,内流流速的增加可有效减小冷水管横流向振动幅值,压载质量可大幅减小冷水管自由端的振动位移。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61377028)the Natural Science Funds for Distinguished Young Scholar,China(Grant No.61125505)the Fundamental Research Funds for the Central Universities,China(Grant No.2014JBZ009)
文摘N-dodecanethiol capped zinc sulfide（Zn S） nanocrystals were synthesized by the one-pot approach and blended with poly（N-vinylcarbazole）（PVK） to fabricate electrical bistable devices. The corresponding devices did exhibit electrical bistability and negative differential resistance（NDR） effects. A large ON/OFF current ratio of 104 at negative voltages was obtained by applying different amplitudes of sweeping voltage. The observed conductance switching and the negative differential resistance are attributed to the electric-field-induced charge transfer between the nanocrystals and the polymer,and the charge trapping/detrapping in the nanocrystals.
文摘以海洋温差能发电(Ocean Thermal Energy Conversion,OTEC)平台的冷水管为研究对象,根据结构方程和尾流振子方程建立冷水管流固耦合模型,采用有限元方法和Newmark-β法对冷水管涡激振动(Vortex-Induced Vibration,VIV)进行时域分析,并在MATLAB软件中开发相应的求解程序。针对冷水管所面临的复杂工况,分别研究外部流场、内部流场、长径比和压载质量等因素对VIV产生的影响。结果表明:随着外流流速和长径比的增大,冷水管横流向VIV模态和振动幅值也发生相应改变,振动强度呈现波动上升;在不发生动态失稳的情况下,内流流速的增加可有效减小冷水管横流向振动幅值,压载质量可大幅减小冷水管自由端的振动位移。
