兰州重离子加速器辐照终端与快重离子辐照效应研究

介绍了兰州重离子加速器辐照终端的基本概况，并就可能开展的研究项目提出了建议。     

高能重离子辐照制备碳氮化合物材料研究

室温下,先用100-120 keV的N离子注入类金刚石薄膜和石墨中,注入剂量5×1017至5×1018 cm-2,再用高能Xe、U、C60离子分别辐照注氮后的样品,然后用显微FTIR和Raman、XRD/XPS等手段进行分析表征,研究了实验样品中由辐照引起的新化学键和新相的产生.实验结果显示,高能重离子辐照可在所有样品中产生大量的CN键,高N浓度和大密度能量沉积导致sp3/sp2键比率的增加以及形成α-和β-C3N4必需的N-sp3C键的量的增加.C60离子辐照在注氮石墨样品中引起了ta-C、N=sp2C和N-sp3C键的形成;而高能离子辐照在注氮类金刚石薄膜样品中产生了α-和β-C3N4晶态夹杂物,其尺寸在1.4-3.6 nm之间.     

用重离子辐照制备核微孔滤膜

用加速器引出的重离子束制备核微孔滤膜的优点是:能够提供多种单能、均匀、垂直的高能重离子束,因而它已成为制备核微孔滤膜的理想手段。氧是制备聚碳酸酯核微孔滤膜的临界重离子。本实验用1.5米回旋加速器引出的不同能量的氧离子束探索了照射方法、化学蚀刻条件及核微孔滤膜的化学稳定性等,制得了一定规格的核微孔滤膜。     

兰州重离子加速器细胞辐照装置

介绍了重离子加速器上专门设计的用于动物细胞研究的辐照装置，用聚碳酸酯薄膜蚀刻法研究了该装置的辐照均匀性，并着重讨论了辐照剂量大小对辐照均匀度的影响。     

重离子辐照模拟的实验验证(英文)

采用正电子湮没寿命技术研究了等效剂量的5.28×1016cm-2 85 MeV氟离子和3×1020cm-2En≥1 MeV中子辐照的α-Al2O3中产生的辐射损伤及其细致的热退火行为。实验结果表明重离子辐照的α-Al2O3中的正电子湮没寿命及其强度与中子辐照的α-Al2O3中的完全符合,从实验上验证了重离子辐照可以很好地模拟中子(质子)的辐照。     

重离子辐照装置控制系统准确性

研究了HIRFL上重离子辐照装置控制系统准确性,结果表明实验系统剂量的准确与剂量率有关,在一定的剂量下要选择合适的剂量率可保持控制系统的准确,同时在考虑精确剂量时,应修正实验数据。     

HI—13串列加速器重离子扫描辐照装置

介绍了ＨＩ－１３串列加速器重离子扫描辐照装置的研制结果。其技术和工艺有如下特点：（１）能对１００—２００ＭｅＶ能区的重离子进行扫描；（２）采用二维（ｘ，ｙ）扫描方式；（３）小巧紧凑的扫描磁铁；（４）特制的磁极内陶瓷束流管道；（５）使用了三角波扫描磁场电源；（６）紧凑精密的扫描靶室和辐照传动靶室。该装置可满足核孔膜高级滤材、大功率快速电子器件改性以及生物样品等重离子均匀辐照的需要。     

重离子辐照诱导DNA双链断裂的剂量率效应

利用不同剂量率的50MeV/u^12C^6 辐照B16黑色素瘤细胞的脱蛋白DNA,采用脉冲场凝胶电泳技术对DNA双链断裂（DSB）的诱导和片段的分布进行了研究。结果发现,在剂量率分别为3Gy/min和30Gy/min的情况下,DNA片段释放百分比（PR）都随着剂量的增加而增加,并在超过一定剂量之后趋于相似的准阈值;3Gy/min辐照诱导DSB的产额为0.40DSBs(100Mbp.Gy）,30Gy/min辐照诱导的DSB产额准确值无法得到;30Gy/min辐照诱导DSB的截面为2.14μm^2,是3Gy/min的3.1掊。所有结果都表明剂量率越高,诱导DSB越有效。另外,3Gy／min辐照诱导DSB片段在－860kbp处有一个片段峰,而30Gy/min没有,说明剂量率可以影响DSB片段的分布。     

重离子和γ辐照硼硅酸盐玻璃的辐照效应对比

为研究玻璃固化体在不同辐照方式下的宏观和微观结果及其对应关系,使用重离子和γ辐照硼硅酸盐玻璃,分别测量了辐照后硼硅酸盐玻璃的硬度和模量变化。发现在γ辐照条件下,直到吸收剂量达到6×10⁶ Gy,硼硅酸盐玻璃的宏观性质（硬度和模量）均未发生明显改变。在Xe离子辐照条件下,当辐照剂量达到0.1 dpa时,硬度和模量减少达饱和值。此外,测量了γ辐照后的硼硅酸盐玻璃的吸收光谱,得到了辐照后硼硅酸盐玻璃带隙随吸收剂量的变化规律,讨论了辐照产生的微观缺陷来源和产生机理。发现重离子辐照产生的硬度和模量的下降主要来源于玻璃网络结构的断裂,而重离子的核能量沉积是造成网络体结构断裂的主要原因。结合γ辐照样品的吸收光谱结果,通过对比γ射线和重离子辐照后的样品硬度和模量变化不同趋势可发现：γ辐照会在硼硅酸盐玻璃中产生微观缺陷（非桥氧空位色心等）,这些缺陷主要来源于网络体末端与钠相连的键的断裂。而网络体末端的断裂不影响硼硅酸盐玻璃的网络体结构,所以γ辐照产生的缺陷不会引起硼硅酸盐玻璃的硬度和模量变化。     

Inhibition of mouse tumors by heavy ion irradiation

1IntroductionCancertreatment'withheavyionsisahighteclmiqueincurrentradiotherapy.Itisoneofthemosteffectivemethodsinthecancertreatment.Duringthecoddle1970s)thegroupatLawrenceBerkeleyLaboratory(LBL)succeededinmodifyingandconnectingitsealstinglow-energyheavy-ionaccelerator(HILAC)toahigh-energyprotonaccelerator(Bevatron)toobtainheavy-ionbeamssuitableforradiotherapy.ThiscombinedfacilitywasknownastheBEVALAC.450patientsweretreatedwithheavyions,mostlyneonattheBevalacofLBL[1].Thegroupreportedp…     

Physiological property and yield of the sweet sorghum mutants induced by heavy ion irradiation

Soil salinity can limit plant growth and productivity. The cultivation of tolerant varieties is convenient and cost-effective for making good use of the saline soils.The sweet sorghum plant has a high tolerance for saline alkaline soils. The KF1210-3 and KF1210-4 early-maturity mutants of sweet sorghum were obtained via carbon ion irradiation. The study assesses the productivity of three sweet sorghum cultivars(KF1210-3, KF1210-4, and KFJTCK) which were grown in intermediate(4.6 d S m~(-1)) and high(11.9 d S m~(-1)) soil salinity. The sweet sorghum grown in the soil salinity of 4.6 d S m~(-1)produced 50.00–57.30 %greater fresh weight than that in the soil salinity of11.9 d S m~(-1), while the difference was not as obvious among the dry biomass of the three sweet sorghum cultivars. Moreover, the Brix degree of the sweet sorghum grown in the soil salinity of 11.9 d S m~(-1)was greater than that grown in the soil salinity of 4.6 d S m~(-1). The heavy ion irradiation experiment is of great significance in screening plant mutants, improving environmental conditions, and assessing the productivity. This process, in turn, aids in the understanding of the effects of the biochemical and physiological mechanisms of salt stress.     

Effects of low-dose heavy ion irradiation on male germ cell adaptation and genetics

1 Introduction Ionizing irradiation has been widely reported to damage organism by attacking proteins, nucleic acid and lipids in cells.[1,2] However, irradiation hormesis after low dose irradiation has been becoming the focus of research in radiobiology in recent years.[3,4] Many studies have shown that low dose ionizing irradiation can produce stimulating effects on the immune sys-tems and induce adaptative response to harmful ef-fects of subsequent high-dose radiation exposure.[3,5-7] Furth…     

Development of function-graded proton exchange membrane for PEFC using heavy ion beam irradiation

The graded energy deposition of heavy ion beam irradiation to polymeric materials was utilized to synthesize a novel proton exchange membrane (PEM) with the graded density of sulfonic acid groups toward the thickness direction. Stacked Poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) films were irradiated by Xe⁵⁴⁺ ion beam with the energy of 6 MeV/u under a vacuum condition. The induced trapped radicals by the irradiation were measured by electron spin resonance (ESR) spectroscopy. Irradiated films were grafted with styrene monomer and then sulfonated. X-ray photo-electron spectroscopy (XPS) spectra showed that the densities of sulfonic acid groups were controlled for injection “Surface” and transmit “Back” sides of the fabricated PEM. The membrane electrode assembly (MEA) fabricated by the function-graded PEM showed improved fuel cell performance in terms of voltage stability. It was expected that the function-graded PEM could control the graded concentration of sulfonic acid groups in PEM.     

Etch-free formation of porous silicon by high-energy ion irradiation

In this study, porous silicon was fabricated without any chemical etching by self-ion implantation of crystalline Si performed at high temperature and at high fluences. The irradiated silicon samples, which remained crystalline under high temperature ion irradiation, exhibited an increased porous fraction with increasing sample temperature at a given fluence, up to the maximum tested temperature of 650 °C. Extremely high ion fluences of at least 2 × 10¹⁸ ions/cm² were necessary to produce significant void growth. Comparisons between the porous silicon structures and irradiation-induced porous networks in Ge, GaSb, and InSb are made, and differences in the formation conditions for these porous networks are discussed.     

高能~(56)Fe离子入射屏蔽材料的次级粒子模拟分析

空间辐射环境下的高能重离子入射屏蔽材料会产生大量次级粒子,为研究屏蔽材料产生的次级粒子对太空舱内辐射环境的影响,本文使用基于蒙特卡罗方法的Geant4软件模拟空间高能~(56)Fe离子入射铝、碳、聚乙烯、水4种屏蔽材料,分析透射屏蔽体的初级粒子及由屏蔽材料产生的次级电子、次级中子、次级质子和次级γ的能谱以及水吸收体中的能量沉积和深度剂量分布。分析产生的次级重粒子类型和能量,比较4种屏蔽材料对高能Fe离子的屏蔽性能。结果表明,聚乙烯材料对高能重离子的屏蔽性能最好,但同时产生的次级重粒子的能量最大,约为铝材料产生次级重粒子能量的4倍。屏蔽体产生所有次级粒子中,次级质子和原子序数为22-26的次级重粒子贡献最大。     

重离子束辐照细胞研究的文献计量学分析

应用文献计量学方法和相应的应用软件,借助Web of Science平台对重离子束辐照细胞这一研究主题的相关文献、作者、期刊、机构以及关键词进行定量和系统考察。结果显示,重离子束辐照细胞研究在1990年之后日益活跃并深入;不同品质的重离子束辐照诱导不同类型细胞会产生不同的生物学效应、旁观者效应及其机制、重离子束辐照细胞生物学效应评估模型、重离子束治疗癌症过程中辐照品质选择与控制模型以及相应的计算机程序是该研究主题的重要内容;引入特定指数推测所得该研究主题重要学术期刊与Nature,Proceedings of the National Academy of Sciences of the United States of America,Cancer Research等期刊之间有较高的共被引频次,表明更多科学前沿的突破性成果和思路应用于该主题研究中;此外,该研究主要集中于少数国家、少数机构、少数作者,并且合作相对较少。     

High-dose neutron induced radiation swelling simulated by heavy ion irradiation and its microscopic study with positron annihilation technique

1IntroductionStainlesssteel(SS)isanimportantreactorstructuralmaterial.SSusedinreactorsexperiencesneutronirradiationandtheaccumulateddosemayreach1022-23n'cm--2alleryearsofreactoroperation.Consequently,severeradiationeffectsoccurinSSandwouldleadtoareactorbreakdownorevenaccident.RadiationsWellingisamajorradiationeffectinSSwhichshouldbetakenintoaccountinreactordesignandoperation.Severeswellinggenerallyoccursatneutrondosesof2102on'cm--2.Thelackofneutronproducingson-rsesofsuchhighdoseshampersits…