Heavy-ion-driven fusion （HIF） is a scheme to achieve inertial confinement fusion （ICF）. Investigation of the non-uniformity of heavy-ion beam （HIB） irradiation is one of the key issues for ICF driven by powerful...Heavy-ion-driven fusion （HIF） is a scheme to achieve inertial confinement fusion （ICF）. Investigation of the non-uniformity of heavy-ion beam （HIB） irradiation is one of the key issues for ICF driven by powerful heavy-ion beams. Ions in HIB impinge on the pellet surface and deposit their energy in a relatively deep and wide area. Therefore, the non-uniformity of HIB irradiation should be evaluated in the volume of the deposition area in the absorber layer. By using the OK1 code with some corrections, the non-uniformity of heavy-ion beam irradiation for the different ion beams on two kinds of targets were evaluated in 12-beam, 20-beam, 60-beam and 120-beam irradiation schemes. The root-mean-square （RMS） non-uniformity value becomes aRMS = 8.39% in an aluminum mono-layer pellet structure and aRMS = 6.53% in a lead-aluminum layer target for the 12-uranium-beam system. The RMS non-uniformity for the lead-aluminum layer target was lower than that for the mono-layer target. The RMS and peak-to-valley （PTV） non-uniformities are reduced with the increase in beam number, and low at the Bragg peak layer.展开更多
SnO_(2)is a potential anode material with high theoretical capacity for lithium-ion batteries(LIBs),however,its applications have been limited by the severe volume expansion during charging-discharging process.In this...SnO_(2)is a potential anode material with high theoretical capacity for lithium-ion batteries(LIBs),however,its applications have been limited by the severe volume expansion during charging-discharging process.In this work,an inverse opal TiO_(2)/SnO_(2)composite with an interconnect network nanostructure was designed to confine Sn O_(2)nanoparticles in the porous TiO_(2).Due to this nanoconfinement structure,the volume expansion in the process was effectively alleviated,therefore the safety performance and cycling stability of the battery were effectively improved.At the same time,with a large number of microporous structures in the framework,the appearance of pseudocapacitance improves the rate performance and reversible capacity.In terms of electrochemical kinetics,its framework provides the connected path for charge migration,effectively reducing the charge transfer impedance,meanwhile,quantities of micropores in its skeleton could provide a smoother channel for lithium ions,thus greatly improving the diffusion rate of LIBs.The design of this nanostructure provides a new idea for the research of SnO_(2)-based anode with effectively enhanced electrochemical performance,which is promising anode for practical application.展开更多
l Ti B中间合金是一种高效实用的铝合金晶粒细化剂。本文指出了Al Ti B的潜力、不足和发展趋势。概述了Al Ti B结构遗传的化学和物理基础及影响因素 ,Al Ti B细化行为的结构遗传效应 ,TiAl3 在铝熔体结构遗传中的动力学行为 ,α Al的形...l Ti B中间合金是一种高效实用的铝合金晶粒细化剂。本文指出了Al Ti B的潜力、不足和发展趋势。概述了Al Ti B结构遗传的化学和物理基础及影响因素 ,Al Ti B细化行为的结构遗传效应 ,TiAl3 在铝熔体结构遗传中的动力学行为 ,α Al的形核机制。提出了新的Al Ti B制备技术和微细化处理工艺。认为随着Al Ti B质量的不断改进 ,尤其是高效洁净稳定型Al Ti B的出现 ,Al Ti展开更多
The split Hopkinson pressure bar （SHPB） method is used to investigate the dynamic behavior of the artificial frozen soil under the nearly uniaxial strain and uniaxial stress conditions. The tests are conducted at th...The split Hopkinson pressure bar （SHPB） method is used to investigate the dynamic behavior of the artificial frozen soil under the nearly uniaxial strain and uniaxial stress conditions. The tests are conducted at the temperatures of -3 ℃, -8 ℃, -13℃, -17℃, -23℃, and -28℃ and with the strain rates from 900 s^-1 to 1500 s^-1. The nearly uniaxial stress-strain curves exhibit an elastic-plastic behavior, whereas the uniaxial stress-strain curves show a brittle behavior. The compressive strength of the frozen soil exhibits the positive strain rate and negative temperature sensitivity, and the final strain of the frozen soil shows the positive strain under the nearly uniaxial strain is greater rate sensitivity. The strength of the frozen soil than that under the uniaxial stress. After the negative confinement tests, the specimens are compressed, and the visible cracks are not observed. However, the specimens are catastrophically damaged after the uniaxial SHPB tests. A phenomenological model with the thermal sensitivity is established to describe the dynamic behavior of the confined frozen soil.展开更多
文摘Heavy-ion-driven fusion （HIF） is a scheme to achieve inertial confinement fusion （ICF）. Investigation of the non-uniformity of heavy-ion beam （HIB） irradiation is one of the key issues for ICF driven by powerful heavy-ion beams. Ions in HIB impinge on the pellet surface and deposit their energy in a relatively deep and wide area. Therefore, the non-uniformity of HIB irradiation should be evaluated in the volume of the deposition area in the absorber layer. By using the OK1 code with some corrections, the non-uniformity of heavy-ion beam irradiation for the different ion beams on two kinds of targets were evaluated in 12-beam, 20-beam, 60-beam and 120-beam irradiation schemes. The root-mean-square （RMS） non-uniformity value becomes aRMS = 8.39% in an aluminum mono-layer pellet structure and aRMS = 6.53% in a lead-aluminum layer target for the 12-uranium-beam system. The RMS non-uniformity for the lead-aluminum layer target was lower than that for the mono-layer target. The RMS and peak-to-valley （PTV） non-uniformities are reduced with the increase in beam number, and low at the Bragg peak layer.
基金support of Project Supported by Keypoint Research and Invention in Shaanxi Province of China(No.2020GY-270)this work was supported by the National Natural Science Foundation of China(No.U22A20144)。
文摘SnO_(2)is a potential anode material with high theoretical capacity for lithium-ion batteries(LIBs),however,its applications have been limited by the severe volume expansion during charging-discharging process.In this work,an inverse opal TiO_(2)/SnO_(2)composite with an interconnect network nanostructure was designed to confine Sn O_(2)nanoparticles in the porous TiO_(2).Due to this nanoconfinement structure,the volume expansion in the process was effectively alleviated,therefore the safety performance and cycling stability of the battery were effectively improved.At the same time,with a large number of microporous structures in the framework,the appearance of pseudocapacitance improves the rate performance and reversible capacity.In terms of electrochemical kinetics,its framework provides the connected path for charge migration,effectively reducing the charge transfer impedance,meanwhile,quantities of micropores in its skeleton could provide a smoother channel for lithium ions,thus greatly improving the diffusion rate of LIBs.The design of this nanostructure provides a new idea for the research of SnO_(2)-based anode with effectively enhanced electrochemical performance,which is promising anode for practical application.
文摘l Ti B中间合金是一种高效实用的铝合金晶粒细化剂。本文指出了Al Ti B的潜力、不足和发展趋势。概述了Al Ti B结构遗传的化学和物理基础及影响因素 ,Al Ti B细化行为的结构遗传效应 ,TiAl3 在铝熔体结构遗传中的动力学行为 ,α Al的形核机制。提出了新的Al Ti B制备技术和微细化处理工艺。认为随着Al Ti B质量的不断改进 ,尤其是高效洁净稳定型Al Ti B的出现 ,Al Ti
基金supported by the National Natural Science Foundation of China (No.11172251)the Open Fund of State Key Laboratory of Frozen Soil Engineering (No.SKLFSE201001)the Fundamental Research Funds for the Central Universities (No.SWJTU09CX069)
文摘The split Hopkinson pressure bar （SHPB） method is used to investigate the dynamic behavior of the artificial frozen soil under the nearly uniaxial strain and uniaxial stress conditions. The tests are conducted at the temperatures of -3 ℃, -8 ℃, -13℃, -17℃, -23℃, and -28℃ and with the strain rates from 900 s^-1 to 1500 s^-1. The nearly uniaxial stress-strain curves exhibit an elastic-plastic behavior, whereas the uniaxial stress-strain curves show a brittle behavior. The compressive strength of the frozen soil exhibits the positive strain rate and negative temperature sensitivity, and the final strain of the frozen soil shows the positive strain under the nearly uniaxial strain is greater rate sensitivity. The strength of the frozen soil than that under the uniaxial stress. After the negative confinement tests, the specimens are compressed, and the visible cracks are not observed. However, the specimens are catastrophically damaged after the uniaxial SHPB tests. A phenomenological model with the thermal sensitivity is established to describe the dynamic behavior of the confined frozen soil.
