In this work, the radiation environment in the target area of a fragment separator is evaluated using FLUKA code. The energy deposition in quadrupole coils is presented to provide guidance for a radiation-resistant ma...In this work, the radiation environment in the target area of a fragment separator is evaluated using FLUKA code. The energy deposition in quadrupole coils is presented to provide guidance for a radiation-resistant magnets design. Results show that neutrons dominate in the prompt radiation field. A compact shielding design is recommended for high radiation areas along with the minimization of air activation in the tunnel in order to minimize the radiation effect on nearby beam lines. The displacements per atom results for the graphite target and copper coils indicate that the effect is insignificant. In addition, the activation level of the target is estimated for workers under possible hands-on maintenance condition.展开更多
The radiation and diffraction problem of a two-dimensional rectangular body with an opening floating on a semi- infinite fluid domain of finite water depth is analysed based on the linearized velocity potential theory...The radiation and diffraction problem of a two-dimensional rectangular body with an opening floating on a semi- infinite fluid domain of finite water depth is analysed based on the linearized velocity potential theory through an analytical solution procedure. The expressions for potentials are obtained by the method of variation separation, in which the unknown coefficients are determined by the boundary condition and matching requirement on the interface. The effects of the position of the hole and the gap between the body and side wall on hydrodynamic characteristics are investigated. Some resonance is observed like piston motion in a moon pool and sloshing in a closed tank because of the existence of restricted fluid domains.展开更多
γ-ray radiation-induced grafting strategy was first employed to immobilize 4-aminobenzo-15-crown-5 onto a covalent organic framework(COF).This endeavor culminated in the successful synthesis of a class of two-dimensi...γ-ray radiation-induced grafting strategy was first employed to immobilize 4-aminobenzo-15-crown-5 onto a covalent organic framework(COF).This endeavor culminated in the successful synthesis of a class of two-dimensional crown ether-modified COFs(named[15C5]n%-(TzDa-G-x%)),marking the maiden utilization of COFs in the realm of^(6)Li/^(7)Li isotope separation.These COFs exhibited swifter adsorption kinetics than alternative adsorbents.Among them,[15C5]_(57%)-(TzDa-G-50%)with its excellent crystallinity,porosity,and stability exhibited the best performance in Li+adsorption and^(6)Li/^(7)Li isotope separation.The Li+adsorption in acetonitrile achieved a capacity of 3.6 mg·g^(−1)within 30 min and a saturation capacity of 7.3 mg·g^(−1).The single-stage separation factor of^(6)Li/^(7)Li isotopes was 1.014±0.001.The results of dynamic adsorption column experiments showed that the packed column made of[15C5]_(57%)-(TzDa-G-50%)maintained stable performance during four cycles of Li+adsorptionelution,with over 99%Li+removal rate in acetonitrile.This crown ether-modified COF has potential application in^(6)Li/^(7)Li isotope separation,and this radiation-assisted synthesis strategy is expected to become universal in the modification of COFs for diverse applications.展开更多
An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal ...An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal and mass balance,this study decoupled the heat transfer processes in the SFS.In accordance with the decoupling conditions,we modeled the spent fuel pool of the CAP1400 pressurized water reactor in Weihai and used computational fluid dynamics to explore the heat dissipation capacity of the SFS under different air temperatures and wind speeds.The results show that the air-cooled separated heat pipe radiator achieved optimal performance at an air temperature of 10℃ or wind speed of 8 m/s.Fitted equations for the equivalent thermal conductivity of the separated heat pipes with the wind speed and air temperature we obtained according to the thermal resistance network model.This study is instructive for the actual operation of an SFS.展开更多
聚丙烯腈(PAN)隔膜具有优秀的电化学性能,作为锂离子电池隔膜材料受到广泛关注,但其机械强度与耐热性不足问题依然存在。本文选用由软段与硬段构成的聚合物热塑性聚氨酯(TPU)与PAN进行混纺,并将制备的纤维膜通过^(60)Coγ射线对其改性,...聚丙烯腈(PAN)隔膜具有优秀的电化学性能,作为锂离子电池隔膜材料受到广泛关注,但其机械强度与耐热性不足问题依然存在。本文选用由软段与硬段构成的聚合物热塑性聚氨酯(TPU)与PAN进行混纺,并将制备的纤维膜通过^(60)Coγ射线对其改性,制备出一种新型锂离子电池隔膜。通过FTIR发现辐照改性PAN/TPU隔膜,PAN分子间出现环化反应,并且PAN与TPU分子间出现C=N-N键的交联,环和交联结构的引入都提高隔膜的力学与耐热性能,此外通过100 k Gy改性后的隔膜电化学性能优异,具有较高的吸液率(552%)与孔隙率(68.2%),电化学稳定窗口为5.42 V,界面阻抗为149.44Ω,离子电导率为1.68×10^(-3)S/cm,均优于辐照前的隔膜,1 C下循环100次后放电容量保持率为96.53%,并在循环测试中表现出优异的倍率性能。展开更多
基金supported by the National Key Research and Development Program of China(No.2017YFC0107700)
文摘In this work, the radiation environment in the target area of a fragment separator is evaluated using FLUKA code. The energy deposition in quadrupole coils is presented to provide guidance for a radiation-resistant magnets design. Results show that neutrons dominate in the prompt radiation field. A compact shielding design is recommended for high radiation areas along with the minimization of air activation in the tunnel in order to minimize the radiation effect on nearby beam lines. The displacements per atom results for the graphite target and copper coils indicate that the effect is insignificant. In addition, the activation level of the target is estimated for workers under possible hands-on maintenance condition.
基金supported by the Lloyd's Register Educational Trust (The LRET) through the joint centre involving University College London, Shanghai Jiao Tong University and Harbin Engineering University
文摘The radiation and diffraction problem of a two-dimensional rectangular body with an opening floating on a semi- infinite fluid domain of finite water depth is analysed based on the linearized velocity potential theory through an analytical solution procedure. The expressions for potentials are obtained by the method of variation separation, in which the unknown coefficients are determined by the boundary condition and matching requirement on the interface. The effects of the position of the hole and the gap between the body and side wall on hydrodynamic characteristics are investigated. Some resonance is observed like piston motion in a moon pool and sloshing in a closed tank because of the existence of restricted fluid domains.
基金the National Natural Science Foundation of China(grant no.U2067212)the National Science Fund for Distinguished Young Scholars(grant no.21925603).
文摘γ-ray radiation-induced grafting strategy was first employed to immobilize 4-aminobenzo-15-crown-5 onto a covalent organic framework(COF).This endeavor culminated in the successful synthesis of a class of two-dimensional crown ether-modified COFs(named[15C5]n%-(TzDa-G-x%)),marking the maiden utilization of COFs in the realm of^(6)Li/^(7)Li isotope separation.These COFs exhibited swifter adsorption kinetics than alternative adsorbents.Among them,[15C5]_(57%)-(TzDa-G-50%)with its excellent crystallinity,porosity,and stability exhibited the best performance in Li+adsorption and^(6)Li/^(7)Li isotope separation.The Li+adsorption in acetonitrile achieved a capacity of 3.6 mg·g^(−1)within 30 min and a saturation capacity of 7.3 mg·g^(−1).The single-stage separation factor of^(6)Li/^(7)Li isotopes was 1.014±0.001.The results of dynamic adsorption column experiments showed that the packed column made of[15C5]_(57%)-(TzDa-G-50%)maintained stable performance during four cycles of Li+adsorptionelution,with over 99%Li+removal rate in acetonitrile.This crown ether-modified COF has potential application in^(6)Li/^(7)Li isotope separation,and this radiation-assisted synthesis strategy is expected to become universal in the modification of COFs for diverse applications.
文摘An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal and mass balance,this study decoupled the heat transfer processes in the SFS.In accordance with the decoupling conditions,we modeled the spent fuel pool of the CAP1400 pressurized water reactor in Weihai and used computational fluid dynamics to explore the heat dissipation capacity of the SFS under different air temperatures and wind speeds.The results show that the air-cooled separated heat pipe radiator achieved optimal performance at an air temperature of 10℃ or wind speed of 8 m/s.Fitted equations for the equivalent thermal conductivity of the separated heat pipes with the wind speed and air temperature we obtained according to the thermal resistance network model.This study is instructive for the actual operation of an SFS.
文摘聚丙烯腈(PAN)隔膜具有优秀的电化学性能,作为锂离子电池隔膜材料受到广泛关注,但其机械强度与耐热性不足问题依然存在。本文选用由软段与硬段构成的聚合物热塑性聚氨酯(TPU)与PAN进行混纺,并将制备的纤维膜通过^(60)Coγ射线对其改性,制备出一种新型锂离子电池隔膜。通过FTIR发现辐照改性PAN/TPU隔膜,PAN分子间出现环化反应,并且PAN与TPU分子间出现C=N-N键的交联,环和交联结构的引入都提高隔膜的力学与耐热性能,此外通过100 k Gy改性后的隔膜电化学性能优异,具有较高的吸液率(552%)与孔隙率(68.2%),电化学稳定窗口为5.42 V,界面阻抗为149.44Ω,离子电导率为1.68×10^(-3)S/cm,均优于辐照前的隔膜,1 C下循环100次后放电容量保持率为96.53%,并在循环测试中表现出优异的倍率性能。
