Late Cenozoic climate changes in China's western interior: a review of research on Lake Qinghai and comparison with other records

IEECAS SKLLQG

Impact of monsoonal climatic change on Holocene overbank flooding along Sushui River；middle reach of the Yellow River；China

IEECAS SKLLQG

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.

Study of the interaction of highly charged ions with SiO2 surface

Highly charged ions (HCIs) AO(q+)/Pbq+ are extracted from ECR source and impacted on solid surface Of SiO2 Sputtering yield as a function of incident angle is measured by multi-channel plate (MCP). The results have been fitted by a new formula. We proposed the cooperation model to explain the formula. The results demonstrate that the potential assisted kinetic sputtering yield increases with the charge state and potential sputtering (PS) could be induced by impact of HCIs. At larger incident angles, the sputtering yield is dominated by elastic collision between HCIs and material atoms. It is found that, smaller the incident angle, larger the contribution from the potential sputtering. (C) 2009 Elsevier B.V. All rights reserved.

V5+-doped Bi3.4Yb0.6Ti3O12 fatigue resistant ferroelectric thin films

In this paper, a serial of Bi3.4Yb0.6Ti3-xVxO12 (BYTV) thin film with different V5+ contents were deposited on Pt/Ti/SiO2/Si substrates by chemical solution deposition (CSD). The crystallized phase and electrical properties of the films were investigated using X-ray diffraction, polarization hysteresis loops, leakage current-voltage, and fatigue test. From our experimental results, it can be found that the ferroelectric properties can be improved greatly using V5+-doped in Bi3.4Yb0.6Ti3O12 (BYT) thin film, compared with the reported BYT thin film. The remanent polarization was enhanced and excellent leakage current characteristic with 10(-11)A at the bias voltage of 4V, which is much lower than the BYT thin film or some reported bismuth layer-structure ferroelectric films. Fatigue test shows that the fabricated films have good anti-fatigue characteristic after 10(10) switching cycles. (c) 2008 Published by Elsevier B.V.

X-ray emission produced by interaction of highly ionized Arq+ ions with metallic targets

This paper studies the X-ray spectra produced by the interaction of highly charged ions of Arq+ (q = 16, 17, 18) with metallic surface of Be, Al, Ni, Mo and Au respectively. The experimental results show that the K alpha X-ray emerges from under the surface of solid in the interaction of ions with targets. The multi-electron excitation occurred in the process neutralization of the Ar16+ in electronic configuration of 1s(2) in metallic surfaces, which produces vacancy in the K shell. Electron from high n state transition to K vacancy gives off X-ray. We find that there is no obvious relation between the shape of X-ray spectra and the different targets. The X-ray yield of incident ions are associated with initial electronic configuration. The X-ray yield of target is related to the kinetic energy of the incident ions.

The single vortex in the FFLO state

In this Letter, we study the generalized Ginzburg-Landau (GL) functional near the tricritical temperature, and obtain the vortex solution of the FFLO state. Furthermore, we investigate the structure of the vortex and find that the vortices shrink when the Zeeman effect is weaken or temperature is lowered. (C) 2010 Elsevier B.V. All rights reserved.

Shell effect on stabilization processes following multi-electron transfer in slow Arq+-Ar (g=6-9, 11) collisions

We experimentally investigate the shell effect on the stabilization processes following the multi-electron transfer in slow collisions of Arq+-Ar (q = 6-9, It) The relative cross-section ratios of multi-electron transfer and of the subsequent stabilization with respect to single-electron capture are measured meanwhile compared with the theoretical results predicted by the classical over-barrier model. Our result indicates that the multi-electron transfer is dominant when the projectile charge is large and the subsequent stabilization shows a dramatic variation if the projectile L-shell configuration becomes open. It shows that the subsequent stabilization processes of multiply excited scattering ions have a strong dependence on the projectile shell. (C) 2010 Elsevier BV All rights reserved.

Inactive and mutagenic effects induced by carbon beams of different LET values in a red yeast strain

To evaluate biological action of microorganism exposed to charged particles during the long distance space exploration. Induction of inactivation and mutation in a red yeast strain Rhodotorula glutinis AY 91015 by carbon beams of different LET values (14.9-120 0 keV mu m(-1)) was investigated It was found that survival curves were exponential, and mutation curves were linear for all LET values The dependence of inactivation cross section on LET approached saturation near 120 0 keV mu m(-1) The imitation cross section saturated when LET was higher than 582 keV mu m(-1) Meanwhile, the highest RBEI for inactivation located at 120 0 key mu m(-1) and the highest RBEm for mutation was at 58.2 key mu m(-1) The experiments imply that the most efficient mutagenic part of the depth dose profile of carbon ion is at the plateau region with intermediate LET value in which energy deposited is high enough to Induce mutagenic lesions but too low to induce over kill effect in the yeast cells (C) 2010 Elsevier B V All rights reserved

A study of low-energy ion induced radiolysis of thiol-containing amino acid cysteine in the solid and aqueous solution states

The radiolysis of cysteine under plasma discharge and irradiation of low-energy Ion beam was investigated. The damage of cysteine in aqueous solution under discharge was assessed via the acid ninhydrin reagent and the yield of cystine produced from the reaction was analyzed by FTIR In addition, the generation of hydrogen sulfide was also identified The destruction of solid cysteine under low-energy ion beam irradiation was estimated via monitoring IR bands of different functional groups (-SH, -NH3, -COO-) of cysteine. and the production of cystine from ion-irradiated solid cysteine after dissolution in water was also verified These results may help us to understand the inactivation of sulphydryl enzymes under direct and indirect interaction with the low-energy ion irradiation (C) 2010 Elsevier B V All rights reserved.

207Rn高自旋态能级结构研究

本论文首先介绍了原子核高自旋态研究的一般概况以及其物理解释的基本理论，然后介绍了在束γ谱学及其实验技术。在此基础上分析和讨论了~(207)Rn核的高自旋态实验研究。利用能量为85Mev到95Mev的~(16)O束流，通过~(196)Pt（~(16)O,5n）~(207)Rn反应布居了~(207)Rn的高自旋态。用十台BGO（AC）HPGe探测器进行了下射线的激发函数、γ-γ-t符合及γ射线的单谱等的测量。基于上述测量，本工作建立了包括17条γ跃迁和18个能级的~(207)Rn的高自旋能级纲图，并且基于实验测量的DCO系数建议了各能级的自旋值。为了从物理上讨论207Rn的核结构，本文利用经验壳模型对它的部分能级组态进行了计算。用一个f_5/2)价中子空穴与208助核芯祸合定性地解释了~(207)Rn的低位激发态。用一个i_(13/2)价中子空穴与~(208)Rn核芯藕合定性地解释了~(207)Rn的高位激发态。

SLEUTH城市扩展模型的应用与准确性评估

基于多时相TM遥感影像,利用SLEUTH模型对沈阳市1988~2004年间的城市扩展过程进行了模拟。采用ROC曲线、多分辨率误差估算和景观指数3种方法对SLEUTH模型在总体预测能力、城市扩展数量、空间位置和空间格局上的模拟准确性给予全面定量评估。结果表明,SLEUTH模型具有可信精度,对城市扩展总体趋势拟合较好,但是对城市扩展空间位置的预测和城市空间格局的表达还有待于提高。

生态场理论在沙地云杉种群更新中的应用

生态场理论是物理生态学的基本理论，它基于植物分布格局、植物生长模型、植物竞争以及资源利用的研究。研究森林草原过渡带上沙地云杉种群在更新中产生的生态场的特性，结果表明：沙地云杉种群生态场是半椭圆形特殊的非均匀场；生态场强度随着与母树距离的增大而变化，开始时迅速增大，３～５ｍ处场强达到最大，然后逐渐下降；由于生态场的重叠而使叠加部分的场强明显增大；生态场的作用范围与坡度、坡长等地形因子及树高、冠半径等测树因子都有密切的关系。长轴半径（Ｒ）与坡度（Ｘ）、坡长（Ｌ）和树高（Ｈ）存在下列多元线性关系：Ｒ＝０．９２３Ｈ＋０．３１６Ｘ＋０．０１５Ｌ－４．３１４（ｒ＝０．８２５）

文冠果化学成分预试与综合利用的研究

文冠果干种仁含粗脂肪60％、粗蛋白26％．粗纤维0．34％，淀粉0．9％．总糖2．6％．文冠果皂甙0．5％，17种氨基酸．18种微量元素：文冠果叶含12种微量元素．19．8％的粗蛋白和16种氨基酸。对种壳、果皮、果柄等部位的化学组分也做了分析．指出了综合利用的前景。