高温注氦及随后230MeV的~(208)Pb~(27+)辐照Al_2O_3的光致发光谱的研究

主要研究了110keV的He~+高温注入Al_2O_3单晶及1.1MeV/u的~(208)Pb~(27+)辐照注氦Al_2O_3样品的光致发光的特性。从测试结果可以清楚地看到在375nm,413nm和450nm处出现了强烈的发光峰。并且在600K,5×10~(16) ions/cm~2剂量点,样品的发光峰是最强的。这表明He~+注入Al_2O_3后使带隙中深的辐射中心复合的效率大幅度提高,极大的增强了其发光强度,而且发光伴随着蓝移现象。而经过高能~(208)Pb~(27+)辐照后的样品,在390nm出现了新的发光峰,从FTIR谱中我们能够看到,可能是~(208)Pb~(27+)辐照相对沉积膜出现一定的晶化,其中含有许多纳米尺寸的Al_2O_3晶粒所致。

同位素~(208)Pb靶的制备

介绍了一种弧形靶框夹芯208Pb靶的制备工艺,包括核靶的制备装置和制备方法、核靶厚度和均匀性的控制和测量方法,并对结果进行了讨论。制备采用旋转蒸镀法,该法可以大大提高材料的利用率。所制靶的结构为30μg/cm2C+361μg/cm2208Pb+15μg/cm2C,同一次所制的靶平均厚度为361μg/cm2,不均匀性小于9.8%。其性能能够很好地满足超重核实验研究的要求。

强流高电荷态Pb离子束的产生与优化研究(英文)

随着原子物理及表面物理研究的发展,高电荷态金属离子束的需求日益增多.近来,在中国科学院近代物理研究所14.5GHzLECR3离子源实验平台上,以炉子法产生的铅离子束作为研究对象,进行了一系列ECR离子源关键参数(如:磁场、炉子功率、掺气等)影响高电荷态铅离子束产额的实验研究,在此基础上,调整优化了LECR3离子源的状态参数,从而获得了强流高电荷态铅离子束18eμA207pb30+和6.7eμA207pb37+.

高能Pb离子辐照注碳SiO_2的红外谱研究

室温下,先用120keV的C离子注入二氧化硅薄膜样品至剂量2.0×1017,5.0×1017或8.6×1017ions/cm2,再用950MeV的Pb离子分别辐照至剂量5.0×1011,1.0×1012或3.8×1012ions/cm2,然后测量样品的傅里叶变换红外(FTIR)光谱.通过分析测量得到的傅里叶变换红外谱,发现Pb离子辐照在注碳SiO2样品中可引起大量的Si—C和Si(C)—O—C等化学键的形成,大剂量Pb离子辐照可在大剂量注碳的SiO2中产生分子CO2.大量的Si—C键的存在和分子CO2的形成,预示着高能Pb离子辐照在注碳SiO2样品中有可能形成了纳米Si团簇和/或SiC晶粒.

Atmospheric cu and pb deposition and transport in lake sediments in a remote mountain area；northern China

IEECAS SKLLQG

Assessing soil erosion rates on manually-tilled hillslopes in the Sichuan Hilly Basin using Cs-137 and Pb-210(ex) measurements

IEECAS SKLLQG

具有Pb衬的Tb薄靶的制备

采用滚压法制备Ｔｂ靶，采用滚压法或真空蒸发法制得Ｐｂ膜，两者通过滚压或真空蒸发法结合制得了带Ｐｂ村的Ｔｂ薄靶。

50MeV/u~(20)Na+~(208)Pb→p+~(19)Ne+~(208)Pb反应的探测效率模拟

用半经典模型考虑20Ｎａ＋２０８Ｐｂ→ｐ＋１９Ｎｅ＋２０８Ｐｂ的Ｃｏｕｌｏｍｂ解离过程。用ＭｏｎｔｅＣａｒｌｏ方法计算前角放置的望远镜阵列对Ｃｏｕｌｏｍｂ解离碎片的探测效率。讨论了天体环境下ｐ＋１９Ｎｅ→２０Ｎａ俘获反应道的低能级共振截面测量的可行性。

Sputtering induced by highly charged Pb-208(q+) bombardment on Al surface

Highly charged ions (HCls) carrying high Coulomb potential energy (E-p) could cause great changes in the physical and chemical properties of material surface when they bombard on the solid surface. In our work, the secondary ion yield dependence on highly charged Pbq+ (q = 4-36) bombardment on Al surface has been investigated. Aluminum films (99.99%) covered with a natural oxide film was chosen as our target and the kinetic energy (E-k) was varied between 80 keV and 400 keV. The yield with different incident angles could be described well by the equation developed by us. The equation consists of two parts due to the kinetic sputtering and potential sputtering. The physical interpretations of the coefficients in the said equation are discussed. Also the results on the kinetic sputtering produced by the nuclear energy loss on target Surface are presented.

Multi-quasiparticle gamma-band structure in neutron-deficient Ce and Nd isotopes

The newly developed multi-quasiparticle triaxial projected shell model approach is employed to study the high-spin band structures in neutron-deficient even-even Ce- and Nd-isotopes. It is observed that gamma-bands are built on each intrinsic configuration of the triaxial mean-field deformation. Due to the fact that a triaxial configuration is a superposition of several K-states, the projection from these states results in several low-lying bands originating from the same intrinsic configuration. This generalizes the well-known concept of the surface gamma-oscillation in deformed nuclei based on the ground-state to gamma-bands built on multi-quasiparticle configurations. This new feature provides an alternative explanation on the observation of two I = 10 aligning states in Ce-134 and both exhibiting a neutron character. (C) 2009 Elsevier B.V. All rights reserved.