Based on the structure design and results of neutronics analysis of the CH HCSB TBM (Chinese helium cooled solid breeder test blanket module), thermal hydraulic and mechanical analyses have been carried out. Results s...Based on the structure design and results of neutronics analysis of the CH HCSB TBM (Chinese helium cooled solid breeder test blanket module), thermal hydraulic and mechanical analyses have been carried out. Results show that the design of the CH HCSB TBM is reasonable and acceptable.展开更多
In this study,to better understand the reaction mechanism between inorganic salts and nitrocellulose,CaCO_(3) and Li_(2)CO_(3) were evaluated with respect to their effects on the thermal degradation of NC in nitrogen ...In this study,to better understand the reaction mechanism between inorganic salts and nitrocellulose,CaCO_(3) and Li_(2)CO_(3) were evaluated with respect to their effects on the thermal degradation of NC in nitrogen atmosphere using TG/DSC at three different heating rates(2,5,10 K/min).The numerical relationship between activation energy(E)and conversion rate was obtained by FWO and KAS method,and it was discovered that CaCO_(3) could improve the thermal stability of NC.Activation energy values were calculated by Kissinger method,and it was found that NC that contain Li2CO3had the highest activation energy while NC containing CaCO3had the lowest E value.By combining the thermal analysis data with Malek method,the most probable mechanism model of thermal degradation is obtained as Sesták-Berggren model,which expression is f(α)=α^(m)(1-α)^(n).As a result of this study,there are certain guiding principles that can be applied to the pyrolysis reaction model and to the actual production process of nitrocellulose.展开更多
HALT(highly accelerated life test) is a new reliability test technique.This paper uses nonlinear finite element method to analyze the stress strain characteristic of solder joints of PQFP(plastic quad flat packaging) ...HALT(highly accelerated life test) is a new reliability test technique.This paper uses nonlinear finite element method to analyze the stress strain characteristic of solder joints of PQFP(plastic quad flat packaging) and BGA(ball grid array) under thermal cycle test,and studies influences of profile parameters of the thermal cycle,such as hot and cold soak temperature,hot and cold soak time and temperature change rate,on elastic strain range,accumulated plastic strain,fatigue life and test efficiency of two types of solder joints.Based on the above research and experimental verification,this paper presents the method to build an optimal thermal cycling profile for HALT of electronic components.展开更多
文摘Based on the structure design and results of neutronics analysis of the CH HCSB TBM (Chinese helium cooled solid breeder test blanket module), thermal hydraulic and mechanical analyses have been carried out. Results show that the design of the CH HCSB TBM is reasonable and acceptable.
基金the National Natural Science Foundation of China(NSFC,Grants No.52176114 and 52111530091)Jiangsu Funding Program for Excellent Postdoctoral Talent。
文摘In this study,to better understand the reaction mechanism between inorganic salts and nitrocellulose,CaCO_(3) and Li_(2)CO_(3) were evaluated with respect to their effects on the thermal degradation of NC in nitrogen atmosphere using TG/DSC at three different heating rates(2,5,10 K/min).The numerical relationship between activation energy(E)and conversion rate was obtained by FWO and KAS method,and it was discovered that CaCO_(3) could improve the thermal stability of NC.Activation energy values were calculated by Kissinger method,and it was found that NC that contain Li2CO3had the highest activation energy while NC containing CaCO3had the lowest E value.By combining the thermal analysis data with Malek method,the most probable mechanism model of thermal degradation is obtained as Sesták-Berggren model,which expression is f(α)=α^(m)(1-α)^(n).As a result of this study,there are certain guiding principles that can be applied to the pyrolysis reaction model and to the actual production process of nitrocellulose.
基金Sponsored by National Advanced Research Project of China (41319030101)
文摘HALT(highly accelerated life test) is a new reliability test technique.This paper uses nonlinear finite element method to analyze the stress strain characteristic of solder joints of PQFP(plastic quad flat packaging) and BGA(ball grid array) under thermal cycle test,and studies influences of profile parameters of the thermal cycle,such as hot and cold soak temperature,hot and cold soak time and temperature change rate,on elastic strain range,accumulated plastic strain,fatigue life and test efficiency of two types of solder joints.Based on the above research and experimental verification,this paper presents the method to build an optimal thermal cycling profile for HALT of electronic components.
