The Jiangmen Underground Neutrino Observatory(JUNO)is a large liquid scintillator detector designed to explore many topics in fundamental physics.In this study,the potential of searching for proton decay in the p→νK...The Jiangmen Underground Neutrino Observatory(JUNO)is a large liquid scintillator detector designed to explore many topics in fundamental physics.In this study,the potential of searching for proton decay in the p→νK^(+)mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification.Moreover,the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals.Based on these advantages,the detection efficiency for the proton decay via p→νK^(+)is 36.9%±4.9%with a background level of 0.2±0.05(syst)±0.2(stat)events after 10 years of data collection.The estimated sensitivity based on 200 kton-years of exposure is 9.6×1033 years,which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies.展开更多
A novel SiC double-trench metal-oxide-semiconductor field effect transistor(MOSFET) with integrated MOS-channel diode is proposed and investigated by Sentaurus TCAD simulation. The new SiC MOSFET has a trench gate and...A novel SiC double-trench metal-oxide-semiconductor field effect transistor(MOSFET) with integrated MOS-channel diode is proposed and investigated by Sentaurus TCAD simulation. The new SiC MOSFET has a trench gate and a stepped-trench source, and features an integrated MOS-channel diode on the top sidewall of the source trench(MT MOS). In the reverse conduction state, the MOS-channel diode turns on firstly to prevent the internal parasitic body diode being activated, and thus reduces the turn-on voltage VFand suppresses the bipolar degradation phenomena. The VFof1.70 V(@Ids=-100 A/cm^(2)) for the SiC MT MOS is 38.2% lower than that of SiC double-trench MOSFET(DT MOS).Meanwhile, the reverse recovery charge Qrrof the MT MOS is 58.7% lower than that of the DT MOS at Iload= 700 A/cm^(2),and thus the reverse recovery loss is reduced. Furthermore, owing to the modulation effect induced by the double trenches,the MT MOS preserves the same superior forward conduction and blocking performance as those of DT MOS, with 22.9% and 18.2% improvement on breakdown voltage and RON,spcompared to the trench gate MOSFET with planar integrated SBD(ST MOS).展开更多
With the application of lightweight materials such as advanced high-strength steel and aluminum alloy in the automotive industry, it is necessary to quantitatively evaluate the ultimate deformation capacity of materia...With the application of lightweight materials such as advanced high-strength steel and aluminum alloy in the automotive industry, it is necessary to quantitatively evaluate the ultimate deformation capacity of materials under various plane stress states for the digital simulation of these materials. Conventional Nakajima test can only provide three regular plane stress states, such as tension, plane strain tension and bulging, and FLC curve is affected by deformation path, mold lubrication and other variables. More importantly, Nakajima test cannot provide shear, tension shear, which are extremely important loading conditions in automobile collisions. Therefore, the research work of this paper focuses on the evaluation of the ultimate ductile fracture behavior of sheet metals under various conditions of plane stress states. The four variables Mohr-Coulomb model was established to study the ductile fracture of metal sheets under plane stress states. Beginning with the recorded minor and major strain distributing on the deformation area of uniaxial tension samples, Moving Regression Algorithm was deployed to reveal the inherent relationship among the key parameters involved in the M-C model, which also provided an experimental technique for monitoring the instantaneous changing of triaxiality over the whole loading period. Three or four typical types of uniaxial-loading specimens were well designed to determine the M-C curve. As a result, M-C curve and the transformed major stain vs. minor strain curve provide further information about the material arrest to the ductile fracture in the area of shear loading, in comparison with the conventional FLD test.展开更多
基金supported by the Chinese Academy of Sciencesthe National Key R&D Program of China+22 种基金the CAS Center for Excellence in Particle PhysicsWuyi Universitythe Tsung-Dao Lee Institute of Shanghai Jiao Tong University in Chinathe Institut National de Physique Nucléaire et de Physique de Particules (IN2P3) in Francethe Istituto Nazionale di Fisica Nucleare (INFN) in Italythe Italian-Chinese collaborative research program MAECI-NSFCthe Fond de la Recherche Scientifique (F.R.S-FNRS)FWO under the "Excellence of Science-EOS" in Belgiumthe Conselho Nacional de Desenvolvimento Científico e Tecnològico in Brazilthe Agencia Nacional de Investigacion y Desarrollo in Chilethe Charles University Research Centrethe Ministry of Education,Youth,and Sports in Czech Republicthe Deutsche Forschungsgemeinschaft (DFG)the Helmholtz Associationthe Cluster of Excellence PRISMA+ in Germanythe Joint Institute of Nuclear Research (JINR)Lomonosov Moscow State University in Russiathe joint Russian Science Foundation (RSF)National Natural Science Foundation of China (NSFC) research programthe MOST and MOE in Taiwan,Chinathe Chulalongkorn UniversitySuranaree University of Technology in Thailandthe University of California at Irvine in USA
文摘The Jiangmen Underground Neutrino Observatory(JUNO)is a large liquid scintillator detector designed to explore many topics in fundamental physics.In this study,the potential of searching for proton decay in the p→νK^(+)mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification.Moreover,the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals.Based on these advantages,the detection efficiency for the proton decay via p→νK^(+)is 36.9%±4.9%with a background level of 0.2±0.05(syst)±0.2(stat)events after 10 years of data collection.The estimated sensitivity based on 200 kton-years of exposure is 9.6×1033 years,which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies.
基金the support by the Science & Technology Program (High voltage and high power SiC material, devices and the application demonstration in power electronic transformers) of the State Grid Corporation of China Co. Ltd.supported by the National Key Research and Development Program of China (Grant No. 2016YFB0400502)。
文摘A novel SiC double-trench metal-oxide-semiconductor field effect transistor(MOSFET) with integrated MOS-channel diode is proposed and investigated by Sentaurus TCAD simulation. The new SiC MOSFET has a trench gate and a stepped-trench source, and features an integrated MOS-channel diode on the top sidewall of the source trench(MT MOS). In the reverse conduction state, the MOS-channel diode turns on firstly to prevent the internal parasitic body diode being activated, and thus reduces the turn-on voltage VFand suppresses the bipolar degradation phenomena. The VFof1.70 V(@Ids=-100 A/cm^(2)) for the SiC MT MOS is 38.2% lower than that of SiC double-trench MOSFET(DT MOS).Meanwhile, the reverse recovery charge Qrrof the MT MOS is 58.7% lower than that of the DT MOS at Iload= 700 A/cm^(2),and thus the reverse recovery loss is reduced. Furthermore, owing to the modulation effect induced by the double trenches,the MT MOS preserves the same superior forward conduction and blocking performance as those of DT MOS, with 22.9% and 18.2% improvement on breakdown voltage and RON,spcompared to the trench gate MOSFET with planar integrated SBD(ST MOS).
文摘With the application of lightweight materials such as advanced high-strength steel and aluminum alloy in the automotive industry, it is necessary to quantitatively evaluate the ultimate deformation capacity of materials under various plane stress states for the digital simulation of these materials. Conventional Nakajima test can only provide three regular plane stress states, such as tension, plane strain tension and bulging, and FLC curve is affected by deformation path, mold lubrication and other variables. More importantly, Nakajima test cannot provide shear, tension shear, which are extremely important loading conditions in automobile collisions. Therefore, the research work of this paper focuses on the evaluation of the ultimate ductile fracture behavior of sheet metals under various conditions of plane stress states. The four variables Mohr-Coulomb model was established to study the ductile fracture of metal sheets under plane stress states. Beginning with the recorded minor and major strain distributing on the deformation area of uniaxial tension samples, Moving Regression Algorithm was deployed to reveal the inherent relationship among the key parameters involved in the M-C model, which also provided an experimental technique for monitoring the instantaneous changing of triaxiality over the whole loading period. Three or four typical types of uniaxial-loading specimens were well designed to determine the M-C curve. As a result, M-C curve and the transformed major stain vs. minor strain curve provide further information about the material arrest to the ductile fracture in the area of shear loading, in comparison with the conventional FLD test.
