Ion irradiation is usually used to simulate neutron irradiation to accelerate the evaluation of the irradia-tion behavior of reactor materials.However,the validity of using a high damage rate of ion irradiation to sim...Ion irradiation is usually used to simulate neutron irradiation to accelerate the evaluation of the irradia-tion behavior of reactor materials.However,the validity of using a high damage rate of ion irradiation to simulate a low damage rate of neutron irradiation has always been a controversial topic.Here,the effect of two dose rates(2.94×10^(-6) and 7.35×10^(-5) dpa s^(-1))on the characteristics and evolution of dislo-cation loops in palladium was studied in situ during 30 keV H2+irradiation using transmission electron microscopy.The dose rate obviously affected the nucleation rate and growth rate of dislocation loops,the types(Frank loops or perfect loops)of dislocation loops,and the irradiation hardening and total damage obtained from the product of average loop size and loop density.At the same irradiation dose,a high dose rate would lead to high loop density,small average loop size,low loop growth rate,and low irra-diation hardening and damage induced by loops in pure Pd.Meanwhile,it was found for the first time that a high dose rate was beneficial to the generation of perfect dislocation loops.The effect of dose rate was attributed to the different dynamic equilibrium results between the effective generation rate of point defects and their absorption rate by existing sinks.The present results show that the effect of dose rate should be considered when using ion irradiation to simulate neutron irradiation to evaluate the irradiation damage to materials.展开更多
A High Temperature Gas Cooled Reactor （HTGR） with an outlet coolant temperature of 950 ℃ is considered as an efficient reactor to couple with the thermo-chemical Sulfur Iodine （SI） cycle for a hydrogen production...A High Temperature Gas Cooled Reactor （HTGR） with an outlet coolant temperature of 950 ℃ is considered as an efficient reactor to couple with the thermo-chemical Sulfur Iodine （SI） cycle for a hydrogen production. The test loop was installed in the Korea Atomic Energy Research Institute （KAERI） facility to confirm the integrity of the sulfur trioxide decomposer, one of the key components in the test loop, under HTGR operating conditions. In this paper, the simulation using Aspen plus, a chemical process simulator, was made to evaluate the performance of a sulfur trioxide decomposer. The simulation indicated that at least 10 kW heat needs to be supplied to the sulfur trioxide decomposer in the test loop when the sulfuric acid flowrate is 0.5 kg/min. The simulation flowsheet was obtained and the material balance around the sulfur trioxide decomposer was determined in case of 10 kW heat input and 0.5 kg/min flowrate of liquid sulfuric acid. The parametric study was carried out for sulfur trioxide decomposer. It indicated that the moles of sulfur dioxide produced at the decomposer increases as the operating temperature increases and is decreasing as the operating pressure becomes higher at a given temperature. The parametric study also indicated water vapor removal out of the decomposer is a less effective method to increase the sulfur trioxide conversion ratio.展开更多
The influences of temperature, pressure, catalyst content, H 2O 2 content and mol ratio of propylene to H 2O 2 on epoxidation of propylene with H 2O 2 over TS-1 in a small-scale three phase loop thermosphonic reactor ...The influences of temperature, pressure, catalyst content, H 2O 2 content and mol ratio of propylene to H 2O 2 on epoxidation of propylene with H 2O 2 over TS-1 in a small-scale three phase loop thermosphonic reactor were investigated. The proper reaction condition was determined as follows: mol ratio of propylene to H 2O 2 was 1.1—1.3, temperature was 30—45?℃, reaction temperature rise was below 15?℃, pressure was 0—0.1?MPa, catalyst content was 3%—6%,and H 2O 2 content was 3%—5%.The conversion of H 2O 2 is above 94%,and selectivity of propylene is up to 96%. At these conditions, the yield of PO is higher than a figure of about 80%,which is achieved using conventional reactor. This reactor can realize catalyst regeneration continuously. This viable reactor can also be applied in other oxidation processes using TS-1, i.e. hydroxylation of phenol, ammoxidation of cyclohexanone.The results will lay a foundation for the development of the reactor in propylene epoxidation process.展开更多
为了提高轨道交通用燃料电池混合动力系统的燃料经济性并有效保持储能单元的荷电状态(state of charge,SOC),该文提出一种适用于燃料电池/超级电容混合动力系统的瞬时等效最小氢耗硬件在环方法。该方法采用超级电容的一阶RC等效电路模型...为了提高轨道交通用燃料电池混合动力系统的燃料经济性并有效保持储能单元的荷电状态(state of charge,SOC),该文提出一种适用于燃料电池/超级电容混合动力系统的瞬时等效最小氢耗硬件在环方法。该方法采用超级电容的一阶RC等效电路模型,建立超级电容的等效氢耗模型,通过推导得到超级电容最优输出的功率,根据当前SOC下超级电容最优输出功率并结合需求功率控制燃料电池系统的输出。通过在搭建的RT-LAB半实物硬件在环平台下,与功率跟随方法进行对比分析。结果表明,提出的方法能够有效减少氢气消耗量和保持超级电容SOC,将在轨道交通混合动力车辆大功率应用中具有良好的应用前景。展开更多
基金supported by the National Science Fund for Distinguished Young Scholars of China (Grant No.12225506)the National Natural Science Foundation of China (Grant No.U1967211 and 11975191)the National MCF Energy R&D Program (Grant No.2022YFE03110000).
文摘Ion irradiation is usually used to simulate neutron irradiation to accelerate the evaluation of the irradia-tion behavior of reactor materials.However,the validity of using a high damage rate of ion irradiation to simulate a low damage rate of neutron irradiation has always been a controversial topic.Here,the effect of two dose rates(2.94×10^(-6) and 7.35×10^(-5) dpa s^(-1))on the characteristics and evolution of dislo-cation loops in palladium was studied in situ during 30 keV H2+irradiation using transmission electron microscopy.The dose rate obviously affected the nucleation rate and growth rate of dislocation loops,the types(Frank loops or perfect loops)of dislocation loops,and the irradiation hardening and total damage obtained from the product of average loop size and loop density.At the same irradiation dose,a high dose rate would lead to high loop density,small average loop size,low loop growth rate,and low irra-diation hardening and damage induced by loops in pure Pd.Meanwhile,it was found for the first time that a high dose rate was beneficial to the generation of perfect dislocation loops.The effect of dose rate was attributed to the different dynamic equilibrium results between the effective generation rate of point defects and their absorption rate by existing sinks.The present results show that the effect of dose rate should be considered when using ion irradiation to simulate neutron irradiation to evaluate the irradiation damage to materials.
文摘A High Temperature Gas Cooled Reactor （HTGR） with an outlet coolant temperature of 950 ℃ is considered as an efficient reactor to couple with the thermo-chemical Sulfur Iodine （SI） cycle for a hydrogen production. The test loop was installed in the Korea Atomic Energy Research Institute （KAERI） facility to confirm the integrity of the sulfur trioxide decomposer, one of the key components in the test loop, under HTGR operating conditions. In this paper, the simulation using Aspen plus, a chemical process simulator, was made to evaluate the performance of a sulfur trioxide decomposer. The simulation indicated that at least 10 kW heat needs to be supplied to the sulfur trioxide decomposer in the test loop when the sulfuric acid flowrate is 0.5 kg/min. The simulation flowsheet was obtained and the material balance around the sulfur trioxide decomposer was determined in case of 10 kW heat input and 0.5 kg/min flowrate of liquid sulfuric acid. The parametric study was carried out for sulfur trioxide decomposer. It indicated that the moles of sulfur dioxide produced at the decomposer increases as the operating temperature increases and is decreasing as the operating pressure becomes higher at a given temperature. The parametric study also indicated water vapor removal out of the decomposer is a less effective method to increase the sulfur trioxide conversion ratio.
文摘The influences of temperature, pressure, catalyst content, H 2O 2 content and mol ratio of propylene to H 2O 2 on epoxidation of propylene with H 2O 2 over TS-1 in a small-scale three phase loop thermosphonic reactor were investigated. The proper reaction condition was determined as follows: mol ratio of propylene to H 2O 2 was 1.1—1.3, temperature was 30—45?℃, reaction temperature rise was below 15?℃, pressure was 0—0.1?MPa, catalyst content was 3%—6%,and H 2O 2 content was 3%—5%.The conversion of H 2O 2 is above 94%,and selectivity of propylene is up to 96%. At these conditions, the yield of PO is higher than a figure of about 80%,which is achieved using conventional reactor. This reactor can realize catalyst regeneration continuously. This viable reactor can also be applied in other oxidation processes using TS-1, i.e. hydroxylation of phenol, ammoxidation of cyclohexanone.The results will lay a foundation for the development of the reactor in propylene epoxidation process.
文摘为了提高轨道交通用燃料电池混合动力系统的燃料经济性并有效保持储能单元的荷电状态(state of charge,SOC),该文提出一种适用于燃料电池/超级电容混合动力系统的瞬时等效最小氢耗硬件在环方法。该方法采用超级电容的一阶RC等效电路模型,建立超级电容的等效氢耗模型,通过推导得到超级电容最优输出的功率,根据当前SOC下超级电容最优输出功率并结合需求功率控制燃料电池系统的输出。通过在搭建的RT-LAB半实物硬件在环平台下,与功率跟随方法进行对比分析。结果表明,提出的方法能够有效减少氢气消耗量和保持超级电容SOC,将在轨道交通混合动力车辆大功率应用中具有良好的应用前景。
