The degradation phenomena due to the energy pulse in the high-energy ZnO varistors used for deexitation and overvoltage protection of hydroelectric generator are investigated. The energy pulse, obtained by releasing t...The degradation phenomena due to the energy pulse in the high-energy ZnO varistors used for deexitation and overvoltage protection of hydroelectric generator are investigated. The energy pulse, obtained by releasing the energy stored in an inductor, can be equivalent to the combination of the DC field components and the energy component. The variations of the characterized voltages, nonlinear coefficients and pre-breakdown V-A characteristics, increase with the number of the applied energy pulse. The asymmetrical variations of the electric properties of the high-energy ZnO varistors after the energy pulse arise from the deformation of the double Schottky barriers due to the ion migration occuring in the depletion layer and in the grain boundary.展开更多
Silicon(Si)is considered a potential alternative anode for next-generation Li-ion batteries owing to its high theoretical capacity and abundance.However,the commercial use of Si anodes is hindered by their large volum...Silicon(Si)is considered a potential alternative anode for next-generation Li-ion batteries owing to its high theoretical capacity and abundance.However,the commercial use of Si anodes is hindered by their large volume expansion(~300%).Numerous efforts have been made to address this issue.Among these efforts,Si-graphite co-utilization has attracted attention as a reasonable alternative for high-energy anodes.A comparative study of representative commercial Si-based materials,such as Si nanoparticles,Si suboxides,and Si−Graphite composites(SiGC),was conducted to characterize their overall performance in high-energy lithium-ion battery(LIB)design by incorporating conventional graphite.Nano-Si was found to exhibit poor electrochemical performance,with severe volume expansion during cycling.Si suboxide provided excellent cycling stability in a full-cell evaluation with stable volume variation after 50 cycles,but had a large irreversible capacity and remarkable volume expansion during the first cycle.SiGC displayed a good initial Coulombic efficiency and the lowest volume change in the first cycle owing to the uniformly distributed nano-Si layer on graphite;however,its long-term cycling stability was relatively poor.To complement each disadvantage of Si suboxide and SiGC,a new combination of these Si-based anodes was suggested and a reasonable improvement in overall battery performance was successfully achieved.展开更多
Neutrons （2.45MeV） from deuterium cluster fusion induced by the intense femtosecond （3Ors） laser pulse are experimentally demonstrated. The average neutron yield 103 per shot is obtained. It is found that the yiel...Neutrons （2.45MeV） from deuterium cluster fusion induced by the intense femtosecond （3Ors） laser pulse are experimentally demonstrated. The average neutron yield 103 per shot is obtained. It is found that the yield slightly increases with the increasing laser spot size. No neutron can be observed when the laser intensity I 〈 4.3 × 10^15 W/cm^2.展开更多
Ternary and quadruple lithium silicon nitride anode materials for lithium ion batteries with different precursors were prepared by the simple process of high-energy ball milling. High capacity and excellent cyclabilit...Ternary and quadruple lithium silicon nitride anode materials for lithium ion batteries with different precursors were prepared by the simple process of high-energy ball milling. High capacity and excellent cyclability were obtained. The influence of precursor introduction on the electrochemical performance of products was investigated. This research reveals that the electrochemical performance of lithium silicon hitilde can be enhanced significantly by doping O. The cyclability of quadruple lithium silicon nitfide can be optimized remarkably by controlling the introduction quantity of the precursors. It is possible for the composite to be used as a capacity compensator within a wide voltage cut-off window.展开更多
In this paper, we studied the process of dissociation unimolecular of the evaporation of H+2n+1 hydrogen clusters according to size, using the Rice-Ramsperger-Kassel-Marcus (RRKM) theory. The rate constants k(E) were ...In this paper, we studied the process of dissociation unimolecular of the evaporation of H+2n+1 hydrogen clusters according to size, using the Rice-Ramsperger-Kassel-Marcus (RRKM) theory. The rate constants k(E) were determined with the use of statistical theory of unimolecular reactions using various approximations. In our work, we used the products frequencies instead of transitions frequencies in the calculation of unimolecular dissociation rates obtained by three models RRKM. The agreement between the experimental cross section ratio and calculated rate ratio with direct count approximation seems to be reasonable.展开更多
白龙港污泥干化焚烧工程建设规模为486 t DS/d,为亚洲最大的污泥独立干化焚烧项目。该项目臭气排放标准需满足国内较为严格的标准之一:上海地标《恶臭(异味)污染物排放标准》(DB 31/1025—2016)。除臭工程设计方面,在全面分析干化焚烧...白龙港污泥干化焚烧工程建设规模为486 t DS/d,为亚洲最大的污泥独立干化焚烧项目。该项目臭气排放标准需满足国内较为严格的标准之一:上海地标《恶臭(异味)污染物排放标准》(DB 31/1025—2016)。除臭工程设计方面,在全面分析干化焚烧厂臭气散发源的基础上,通过对重点区域的有效隔断和密闭,加之送风和吸风对侧布置的除臭管路设计,形成气体对流,从而完成高效的臭气收集。同时,在重点区域辅以植物液除臭,车间物流大门设置离子风幕。除臭工艺选用“离子送风+生物滤池+化学洗涤+活性炭吸附”的四级组合式除臭工艺,确保了最终的除臭效果。排气筒和厂界均能达到上海新地标的排放要求。展开更多
文摘The degradation phenomena due to the energy pulse in the high-energy ZnO varistors used for deexitation and overvoltage protection of hydroelectric generator are investigated. The energy pulse, obtained by releasing the energy stored in an inductor, can be equivalent to the combination of the DC field components and the energy component. The variations of the characterized voltages, nonlinear coefficients and pre-breakdown V-A characteristics, increase with the number of the applied energy pulse. The asymmetrical variations of the electric properties of the high-energy ZnO varistors after the energy pulse arise from the deformation of the double Schottky barriers due to the ion migration occuring in the depletion layer and in the grain boundary.
基金the Technology Innovation Program(No.20010542,Development of Petroleum Pitch Based Conductive Material and Binder for Lithium Ion Secondary Battery and Their Application)funded by the Ministry of Trade,Industry&Energy(MOTIE,Republic of Korea)the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2021R1A2C1095408).
文摘Silicon(Si)is considered a potential alternative anode for next-generation Li-ion batteries owing to its high theoretical capacity and abundance.However,the commercial use of Si anodes is hindered by their large volume expansion(~300%).Numerous efforts have been made to address this issue.Among these efforts,Si-graphite co-utilization has attracted attention as a reasonable alternative for high-energy anodes.A comparative study of representative commercial Si-based materials,such as Si nanoparticles,Si suboxides,and Si−Graphite composites(SiGC),was conducted to characterize their overall performance in high-energy lithium-ion battery(LIB)design by incorporating conventional graphite.Nano-Si was found to exhibit poor electrochemical performance,with severe volume expansion during cycling.Si suboxide provided excellent cycling stability in a full-cell evaluation with stable volume variation after 50 cycles,but had a large irreversible capacity and remarkable volume expansion during the first cycle.SiGC displayed a good initial Coulombic efficiency and the lowest volume change in the first cycle owing to the uniformly distributed nano-Si layer on graphite;however,its long-term cycling stability was relatively poor.To complement each disadvantage of Si suboxide and SiGC,a new combination of these Si-based anodes was suggested and a reasonable improvement in overall battery performance was successfully achieved.
基金Supported by the National Natural Science Foundation of China under Grant No 10535030, and the Key Foundation of China Academy of Engineering Physics under Grant No 2006Z0202.
文摘Neutrons （2.45MeV） from deuterium cluster fusion induced by the intense femtosecond （3Ors） laser pulse are experimentally demonstrated. The average neutron yield 103 per shot is obtained. It is found that the yield slightly increases with the increasing laser spot size. No neutron can be observed when the laser intensity I 〈 4.3 × 10^15 W/cm^2.
基金This study is f'mancially supported by the National Natural Science Foundation of China (No.50502009)the Natural Science Foundation of Liaoning Province of China (No.20072146).
文摘Ternary and quadruple lithium silicon nitride anode materials for lithium ion batteries with different precursors were prepared by the simple process of high-energy ball milling. High capacity and excellent cyclability were obtained. The influence of precursor introduction on the electrochemical performance of products was investigated. This research reveals that the electrochemical performance of lithium silicon hitilde can be enhanced significantly by doping O. The cyclability of quadruple lithium silicon nitfide can be optimized remarkably by controlling the introduction quantity of the precursors. It is possible for the composite to be used as a capacity compensator within a wide voltage cut-off window.
文摘In this paper, we studied the process of dissociation unimolecular of the evaporation of H+2n+1 hydrogen clusters according to size, using the Rice-Ramsperger-Kassel-Marcus (RRKM) theory. The rate constants k(E) were determined with the use of statistical theory of unimolecular reactions using various approximations. In our work, we used the products frequencies instead of transitions frequencies in the calculation of unimolecular dissociation rates obtained by three models RRKM. The agreement between the experimental cross section ratio and calculated rate ratio with direct count approximation seems to be reasonable.
文摘白龙港污泥干化焚烧工程建设规模为486 t DS/d,为亚洲最大的污泥独立干化焚烧项目。该项目臭气排放标准需满足国内较为严格的标准之一:上海地标《恶臭(异味)污染物排放标准》(DB 31/1025—2016)。除臭工程设计方面,在全面分析干化焚烧厂臭气散发源的基础上,通过对重点区域的有效隔断和密闭,加之送风和吸风对侧布置的除臭管路设计,形成气体对流,从而完成高效的臭气收集。同时,在重点区域辅以植物液除臭,车间物流大门设置离子风幕。除臭工艺选用“离子送风+生物滤池+化学洗涤+活性炭吸附”的四级组合式除臭工艺,确保了最终的除臭效果。排气筒和厂界均能达到上海新地标的排放要求。
