肺部疾病是全球重要的公共卫生问题,其高发病率与死亡率凸显了早期诊断和精准评估的重要性^([1])。然而,现有诊断方法在全面评估肺部病变方面仍存在局限。传统肺功能检查(pulmonary function tests,PFTs)虽然无创便捷,但仅能提供整体肺...肺部疾病是全球重要的公共卫生问题,其高发病率与死亡率凸显了早期诊断和精准评估的重要性^([1])。然而,现有诊断方法在全面评估肺部病变方面仍存在局限。传统肺功能检查(pulmonary function tests,PFTs)虽然无创便捷,但仅能提供整体肺功能参数,难以反映肺部病变的区域异质性,且依赖于患者的良好配合。对于早期局灶性病变,由于肺组织的代偿作用,PFTs结果可能仍处于正常范围,从而延误了疾病的早期诊断和干预^([2])。高分辨率CT(high-resolution computed tomography,HRCT)是评估肺部结构的“金标准”,但电离辐射风险限制了其在儿童、孕妇及需长期随访的慢性肺病患者中的应用^([3])。展开更多
电子探针显微分析(Electron Probe Micro-Analyze,EPMA)作为一种高空间分辨率的微区分析技术,旨在实现对辐照后核燃料中裂变气体Xe的浓度分布、局部富集及迁移行为的准确分析,并揭示辐照损伤对燃料性能的影响。EPMA通过测量X射线的特征...电子探针显微分析(Electron Probe Micro-Analyze,EPMA)作为一种高空间分辨率的微区分析技术,旨在实现对辐照后核燃料中裂变气体Xe的浓度分布、局部富集及迁移行为的准确分析,并揭示辐照损伤对燃料性能的影响。EPMA通过测量X射线的特征谱线,对Xe进行定性和定量分析,并结合透射电镜(Transmission Electron Microscope,TEM)和二次离子质谱仪(Secondary Ion Mass Spectrometry,SIMS)等其他分析技术,以获取更全面的裂变气体行为信息。本文系统总结近年来EPMA在辐照后核燃料Xe浓度分析中的应用,探讨影响分析准确性的关键因素(如样品制备、仪器参数及数据处理方法等),并评述了提高分析精度的优化方法。通过优化实验条件、改进数据处理算法及结合互补分析技术,可显著提升EPMA的定量准确性。未来,EPMA与其他技术的联用将进一步深化对裂变气体行为的理解,为核燃料性能评估提供更可靠的数据支持。展开更多
The Mg alloys with combination of high strength and excellent irradiation resistance are currently re-quired for research reactors.In this work,the novel Mg-3Mn-0.5Ca alloy with a high strength of over 300 MPa has bee...The Mg alloys with combination of high strength and excellent irradiation resistance are currently re-quired for research reactors.In this work,the novel Mg-3Mn-0.5Ca alloy with a high strength of over 300 MPa has been fabricated via co-addition of Mn and Ca elements.Moreover,the Xe ion implantation(300℃/4.5×10^(15)ions/cm^(2))is conducted for pure Mg,Mg-3Mn and Mg-3Mn-0.5Ca alloys.Microstruc-ture characterization shows that the number density of dislocation loops is comparable between Mg-3Mn and pure Mg,while the phase boundary of nano-Mn particles could act as the sink to absorb more Xe atoms,resulting in the abundant formation of Xe bubbles in the matrix of irradiated Mg-3Mn alloy.With further minor addition of Ca element,the formation of Xe bubbles and dislocation loops in Mg-3Mn-0.5Ca alloy has been obviously suppressed,and the abundant grain boundaries(GBs)due to grain refinement then act as the sink region for Xe precipitation.The limited number density of Xe bubbles leads to the extremely low swelling ratio in Mg-3Mn-0.5Ca alloy,∼0.08%.The result above suggests that the Mn and Ca co-addition could enhance the mechanical properties and irradiation tolerance of Mg alloys,si-multaneously.The present low-alloying strategy would provide a new design reference for novel nuclear materials.展开更多
RED DIGITAL CINEMA日前正式发布了全新V-RAPTOR XE摄影机。作为Z Cinema摄影机系列的最新成员,这款新机型延续了V-RAPTOR[X]系列搭载的RED业界领先8K大画幅(VV)全域快门传感器,确保了全球专业人士信赖的影院级影像真实感、宽广动态范...RED DIGITAL CINEMA日前正式发布了全新V-RAPTOR XE摄影机。作为Z Cinema摄影机系列的最新成员,这款新机型延续了V-RAPTOR[X]系列搭载的RED业界领先8K大画幅(VV)全域快门传感器,确保了全球专业人士信赖的影院级影像真实感、宽广动态范围及卓越弱光表现。展开更多
文摘肺部疾病是全球重要的公共卫生问题,其高发病率与死亡率凸显了早期诊断和精准评估的重要性^([1])。然而,现有诊断方法在全面评估肺部病变方面仍存在局限。传统肺功能检查(pulmonary function tests,PFTs)虽然无创便捷,但仅能提供整体肺功能参数,难以反映肺部病变的区域异质性,且依赖于患者的良好配合。对于早期局灶性病变,由于肺组织的代偿作用,PFTs结果可能仍处于正常范围,从而延误了疾病的早期诊断和干预^([2])。高分辨率CT(high-resolution computed tomography,HRCT)是评估肺部结构的“金标准”,但电离辐射风险限制了其在儿童、孕妇及需长期随访的慢性肺病患者中的应用^([3])。
文摘电子探针显微分析(Electron Probe Micro-Analyze,EPMA)作为一种高空间分辨率的微区分析技术,旨在实现对辐照后核燃料中裂变气体Xe的浓度分布、局部富集及迁移行为的准确分析,并揭示辐照损伤对燃料性能的影响。EPMA通过测量X射线的特征谱线,对Xe进行定性和定量分析,并结合透射电镜(Transmission Electron Microscope,TEM)和二次离子质谱仪(Secondary Ion Mass Spectrometry,SIMS)等其他分析技术,以获取更全面的裂变气体行为信息。本文系统总结近年来EPMA在辐照后核燃料Xe浓度分析中的应用,探讨影响分析准确性的关键因素(如样品制备、仪器参数及数据处理方法等),并评述了提高分析精度的优化方法。通过优化实验条件、改进数据处理算法及结合互补分析技术,可显著提升EPMA的定量准确性。未来,EPMA与其他技术的联用将进一步深化对裂变气体行为的理解,为核燃料性能评估提供更可靠的数据支持。
基金the National Natural Science Foun-dation of China(Nos.U2241235,U2167213 and U2067218)the Project funded by the Science&Technology Department of Sichuan Province(No.21MZGC0400,No.2022JDJQ0021)+3 种基金the China National Nuclear Corporation(CNNC)Science Fund for Talented Young Scholars(No.CNNC-2021-31)the Funds of Science and Technol-ogy on Reactor Fuel and Materials Laboratory(No.6142A06190510)the fund from the Fundamental Research Funds for the Cen-tral Universities(No.N2202020)XingLiao Talent Plan(No.XLYC2203202).
文摘The Mg alloys with combination of high strength and excellent irradiation resistance are currently re-quired for research reactors.In this work,the novel Mg-3Mn-0.5Ca alloy with a high strength of over 300 MPa has been fabricated via co-addition of Mn and Ca elements.Moreover,the Xe ion implantation(300℃/4.5×10^(15)ions/cm^(2))is conducted for pure Mg,Mg-3Mn and Mg-3Mn-0.5Ca alloys.Microstruc-ture characterization shows that the number density of dislocation loops is comparable between Mg-3Mn and pure Mg,while the phase boundary of nano-Mn particles could act as the sink to absorb more Xe atoms,resulting in the abundant formation of Xe bubbles in the matrix of irradiated Mg-3Mn alloy.With further minor addition of Ca element,the formation of Xe bubbles and dislocation loops in Mg-3Mn-0.5Ca alloy has been obviously suppressed,and the abundant grain boundaries(GBs)due to grain refinement then act as the sink region for Xe precipitation.The limited number density of Xe bubbles leads to the extremely low swelling ratio in Mg-3Mn-0.5Ca alloy,∼0.08%.The result above suggests that the Mn and Ca co-addition could enhance the mechanical properties and irradiation tolerance of Mg alloys,si-multaneously.The present low-alloying strategy would provide a new design reference for novel nuclear materials.
