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Guiding of 150 keV O6+ ions through nanocapillaries in an uncoated Al2O3 membrane: special time dependence of the transmission profile width
No full textThis paper reports that the transmission of O6+ ions with energy of 150keV through capillaries in an uncoated Al2O3 membrane was measured, and agreements with previously reported results in general angular distribution of the transmitted ions and the transmission fractions as a function of the tilt angle well fitted to Gaussian-like functions were observed. Due to using an uncoated capillary membrane, our c is larger than that using a gold-coated one with a smaller value of E-p/q, which suggests a larger equilibrium charge Q(infinity) in our experiment. The observed special width variation with time and a larger width than that using a smaller E-p/q were qualitatively explained by using mean-field classical transport theory based on a classical-trajectory Monte Carlo simulation.National Natural Science Foundation of China 1077506
Theoretical calculation of photoionization cross sections of B-like ions: N2+, O3+ and F4+
No full textThere can be found some notable discrepancies with regard to the resonance structures when R-matrix calculations from the Opacity Project and other sources are compared with recent absolute experimental measurements of Bizau et al [Astron. Astrophts. 439 387 (2005)] for B-like ions N2+, O3+ and F4+. We performed close-coupling calculations based on the R-matrix formalism for the photoionizations of ions mentioned above both for the ground states and first excited states in the near threshold regions. The present results are compared with experimental ones given by Bizau et al and earlier theoretical ones. Excellent agreement is obtained between our theoretical results and the experimental photoionization cross sections. The present calculations show a significant improvement over the previous theoretical results.National Natural Science Foundation of China 10674112
Natural Science Foundation of the Gansu Province, China 3ZS061-A25-013
Foundation of Education Department of Gansu Province, China 0601223
Foundation of Northwest Normal University, China NWNU-KJCXGC-03-21
Foundation for Young Teacher of Northwest Normal University, China NWNU-LKQN-08-
Analytical solution of a multidimensional Langevin equation at high friction limits and probability passing over a two-dimensional saddle
No full textThe analytical solution of a multidimensional Langevin equation at the overdamping limit is obtained and the probability of particles passing over a two-dimensional saddle point is discussed. These results may break a path for studying further the fusion in superheavy elements synthesis.National Natural Science Foundation of China 10575075
1044700
STUDIES FOR THE EQUATION OF STATE IN THE ISOSPIN ASYMMETRICAL NUCLEAR INTERACTIONS
No full textIn order to determine the equation of state in the isospin asymmetrical nuclear interactions, we have found the observables for extracting the information of them within the isospin-dependent quantum molecular dynamics in recent years. The several sensitive probes for extracting the information of the in-medium nucleon-nucleon cross section and the symmetry potential have found; meanwhile, their mechanisms are investigated in more details. The main point in this paper gives the summary for above probes and their outlook in the future.National Natural Science Foundation of China 10435080
10447006
10575075
Chinese Academy of Sciences KJCX2-SW-N0
FIRST ISOCHRONOUS MASS MEASUREMENTS AT CSRe
No full textWith the commissioning of the Cooler Storage Ring at the Heavy Ion Research Facility in Lanzhou (HIRFL-CSR), a pilot experiment operating the CSRe in isochronous mode to test the power of HIRFL-CSR for measuring the mass of the short-lived nucleus was performed in December of 2007. The transition point gamma t of CSRe in isochronous mode is 1.395 which corresponds to the energy about 368 MeV/u for the ions with atomic number-to-charge ratio A/q = 2. The fragments with A/q = 2 of Ar-36 were injected into CSRe and their revolution frequencies were measured with a fast time pick-up detector with a thin foil in the circulating path of the ions. A mass resolution of better than 105 for m/Delta m was achieved
Void swelling in MA956 ODS steel irradiated with 122 MeV Ne-ions at elevated temperatures
No full textAn investigation of a commercial oxide dispersion-strengthened steel (MA9561) irradiated with high
energy Ne-ions to high doses at elevated temperatures is presented. Specimens of MA956 oxide dispersion
strengthened steel together with a 9% Cr ferritic/martensitic steel, e.g., Grade 92 steel were irradiated simultaneously
with 20Ne-ions (with 122 MeV) to successively increasing damage levels of 1, 5 and 10 dpa at the
damage peak at 440 C and 570 C, respectively. Cross-sectional microstructures of the specimens were
investigated with transmission electron microscopy. MA956 oxide dispersion strengthened steel showed
a higher resistance to void swelling especially to void growth at the grain boundaries than the ferritic/martensitic
steel, e.g., Grade 92 steel did, and thus exhibited a prominence for an application in the situation of a
high He production at high temperatures. The suppression of the growth of voids especially at the grain
boundaries in MA956 is ascribed to an enhanced recombination of the point defects and a trapping of Ne
atoms at the interfaces of the yttrium–aluminum oxide particles and the matrix
Electron transfer in fast atomic collisions in the presence of an x-ray laser
No full textWe consider electron capture in fast collisions between a proton and hydrogen in the presence of an intense x-ray laser whose angular frequency omega is close to v(2)/2, where v is the collision velocity. We show that in such a case laser-induced capture becomes possible and that the latter proceeds via both induced photon emission and photon absorption channels and can, in principle, compete with kinematic and radiative electron capture
Influence of Hypericum perforatum Extract on Piglet Infected with Porcine Respiratory and Reproductive Syndrome Virus
No full textTo study the influence of Hypericum perforatum extract (HPE) on piglets infected with porcine respiratory and reproductive syndrome virus (PRRSV), enzyme-labeled immunosorbent assay (ELISA) and cytopathic effect (CPE) were used to determine in vitro whether HPE could induce swine pulmonary alveolar macrophages (PAMs) to secrete IFN-gamma, and whether PRRSV titers in PAMs were affected by the levels of HPE-induced IFN-gamma. HPE (200 mg kg(-1)) was administrated by oral gavage to piglets infected with the PRRSV in vivo to observe whether HPE affected the viremia, lung viral titers, and weight gain of piglets infected with PRRSV. The results showed that HPE was capable of inducing PAMs to produce IFN-gamma in a dose dependent manner and HPE pretreatment was capable of significantly reducing PRRSV viral titers in PAMs (P<0.01). Administration of HPE to the PRRSV-infected animals significantly (P<0.05) reduced viremia over time as compared with the PRRSV-infected animals. But there was not significant decrease in lung viral titers at day 21 post-infection between the HPE-treated animals and the PRRSV-infected control piglets. There were no significant differences in weight gain over time among the HPE-treatment animals, the normal control, and the HPE control animals. The PRRSV-infected animals caused significant (P<0.01) growth retardation as compared with the HPE controls and the normal piglets. It suggested that HPE might be an effective novel therapeutic approach to diminish the PRRSV-induced disease in swine
Study of High-spin Levels in Spherical Nucleus139Ce and Transitional Nucleus189Pt
No full text本论文主要包括以下两部分：
利用能量为 50 MeV 的 12C 束流，通过反应 130Te(12C,3n)产生了 139Ce 的高自旋态。基于标准在束核谱学实验方法，利用由 14 套BGO（AC）HPGe 探测器组成的探测器阵列，进行了 X- γ-t 和γ - γ -t 符合测量，更新并扩展了139Ce 的高自旋能级纲图.139Ce的能级结构具有球形原子核的典型特征，其高自旋态是由单粒子激发形成的。本文利用经验壳模型计算了 139
Ce 的多准粒子激发态能量，研究了其高自旋激发态的多准粒子特性。
利用能量为 88 和 95 MeV 的 18O 束流，通过重离子熔合蒸发反应 176Yb(18O,5n)，布居了 189Pt 的高自旋激发态。实验采用 GEMINI γ射线探测器阵列，进行了 X- γ-t 和γ-γ -t 符合测量。基于γ - γ符合关系、
γ射线相对强度、强度平衡原理和交叉跃迁等信息，建立了新的 189Pt 高自旋态能级纲图。实验观测到基于υi113/ 2 ，υf 5/2(p3/2) 和υi113/ 2 ，υf 5/2(p3/2)组态的转动带以及多准粒子激发能级。其中， υi113/ 2 带的优惠和非优惠旋称分支分别被扩展到 49/2+和 31/2+能级。本工作利用三轴粒子-转子模型分析了基于υi113/ 2 ，υf 5/2(p3/2)组态的转动带性质，分析了它们波函数的主要成分，并建议它们分别具有三轴形变和长椭形变。实验上发现结构非常相近的两个能级序列，我们建议它们具有组态。第一次利用粒子-转子模型计算了这个基于三准粒子组态的转动带能级能量，很好地再现了实验结果，并建议此带具有扁椭形变。由于与这个组态相应的 Nilsson 轨道量子数显示了赝自旋量子数特征，我们建议此三准粒子组态转动带为赝自旋伙伴带
Oxygen Effects of Cells and Mice Irradiated by Different Types of Ray
No full text肿瘤是常见病、多发病，也是对人类健康危害极大的疾病。在放射治疗中，
肿瘤的缺氧细胞及组织是影响放射治疗效果的重要因素之一。细胞在乏氧条件
下受低 LET射线照射时，其敏感性明显下降。因此放射治疗肿瘤的成败很大程
度上取决于对肿瘤区中乏氧部分的杀伤效果。如何减少肿瘤中乏氧细胞对射线
的抗性和增强对正常组织中细胞及富氧细胞辐照的保护作用，一直是肿瘤放射
治疗的一个难题。本文就细胞和小鼠处于不同氧环境下，采用不同LET的射线
辐照对细胞的周期及染色体的影响做了初步研究。其结果可为重离子放射治疗
癌症提供有效的基础数据和理论参考，对治疗计划的制定也具有重要的意义