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L-shell x-ray yields and production cross sections of Zr and Mo bombarded by slow highly charged Ar16+ ions
No full textThe L-shell x-ray yields of Zr and Mo bombarded by slow Ar16+ ions are measured. The energy of the Ar16+ ions ranges from about 150keV to 350keV. The L-shell x-ray production cross sections of Zr and Mo are extracted from these yields data. The explanation of these experimental results is in the framework of the adiabatic directionization and the binding energy modified BEA approximation. We consider, in the slow asymmetric collisions such as Ar and Mo/Zr, the transient united atoms (UA) are formed during the ion-surface interaction and the direct-ionization is the main mechanism for the inner-shell vacancy production. Generally, the theoretical results are in good agreement with the experimental data
Influence of in-medium nucleon-nucleon cross section on the isoscaling parameter alpha
No full textThe influence of in-medium nucleon-nucleon cross section on the isoscaling parameter a is investigated for two couples of central nuclear reactions Ca-40 + Ca-40 and Ca-60 + Ca-40; Sn-112 + Sn-112 and Sn-124 + Sn-124 within the isospin dependent quantum molecular dynamics. The calculated result shows that the influence of the in-medium nucleon-nucleon cross section on the isoscaling parameter a is mainly determined by the corresponding number of collisions, both for isospin dependent and isospin independent parameterizations. The mechanisms behind the effects of the in-medium nucleon-nucleon cross sections on the alpha are investigated in more details.National Natural Science Foundation of China 10435080
10447006
10575075
Chinese Academy of Sciences KJCX2-SW-N02
Basic Research of China G200007740
Photoluminescence of Ar+ implanted sapphire before and after annealing
No full text对注入Ar+后不同晶面取向的蓝宝石晶体在不同退火条件下的光致发光谱进行了分析.分析结果表明:三种晶面取向的蓝宝石样品经Ar+注入后，其光致发光谱中均出现了新的位于506nm处的发光峰；真空和空气气氛下的退火均对样品在506nm处的发光有增强作用，不同晶面取向的样品发光增强程度不同，且发光增强至最大时的退火温度也不同，空气气氛下的退火使样品发光增强程度更为显著.由此可以看出，退火气氛、退火温度和晶面取向均对样品发光峰强度有影响.中国科学院“西部之光”人才培养计划、国家自然科学基金(批准号：10575124)资助的课
Isospin effect of nucleon-nucleon cross section on the isoscaling parameter alpha
No full text对两对重离子中心碰撞系统40C+40Ca 和60Ca+40Ca以及112Sn+112Sn和124Sn+124Sn反应中就同位素标度参数α对于核子-核子碰撞截面的同位旋效应进行了研究.计算结果表明α对同位旋相关核子-核子碰撞截面σmedNNKey Program of the National Natural Science Foundation of China 10435080
National Natural Science Foundation of China 10447006
10575075
Main Direction Program of Knowledge Innovation of the Chinese Academy of Siciences KJCX2-SW-N0
Stress analysis of CR superferric magnet
No full textFinite Element Method is used in this article to analyze the stress of CR superferric magnet. Magnetic force and the stress caused by this force are calculated. The thermal stress and strain of the coil caused by cooling down is also analyzed. The result will be taken as a check for the design of the coil and coilcase, and also as a reference for the optimization of further design and quench protection
Evaluation of sex specificity on oxidative stress induced in lungs of mice irradiated by C-12(6+) ions
No full textThe aim of this work is to identify if there is sex specificity on C-12(6+) ion-induced oxidative damage in mouse lung at different time points. Kun-Ming mice were divided into two groups, each composed of six males and six females: control group and irradiation group with a single acute dose of 4 Gy. Animals were sacrificed at 2, 4 and 12 h respectively, there lungs were removed immediately, and the oxidative stress-related biomarkers were measured by Diagnostic Reagent Kits. The results showed that the relative activities of superoxide dismutase (4 h), catalase (2 h) and Se-dependent glutathione peroxidase (12 h) have significant changes (P < 0.05) between male groups and female groups, suggesting that the lungs of male mice are more sensitive to counteracting the oxidative challenge. Moreover, higher levels of malondiadehyde and lower contents of glutathione were also found in males, indicating that oxidative stress induced by C-12(6+) ion is pronounced in the lungs of males. We thought that these sex-responded differences may be attributed to the influence of sex hormones
Fringing Field Effects of Nonsymmetrical Large Angle Rectangular Type Septum
No full text切割磁铁是环型加速器常用的注入引出元件之一,其在非偏转方向上对束流的影响,直接关系到注入引出束流的轨道匹配。对大角度非对称矩形切割磁铁杂散磁场的影响进行了分析,指出其在非偏转方向上对束流有一定的偏转量,而且此偏转量是不可忽略的。另外,介绍了HIRFL-CSR主环注入切割磁铁对注入轨道匹配的影响,并提出了一种补偿方案,进行了初步的补偿。As important components, magnet septums are often used to separate beams inside and outside ring accelerators. If the septum has bending effect on non-intended bending direction, it will influence orbit matching. The fringing field effects of non-symmetrical large angle rectangular type septum is investi-gated in this paper. In some condition, the non-intended bending can＇t be neglected. One of the method to compensate the non-intended bending of septum is introduced in CSRm injection line.中国科学院百人计划资助项目（0313010BR0）; 国家九五大科学工程冷却储存环资助项目（06HIRFL200
HIRFL-CSR实验环中束流损失机制及寿命研究
No full text分析了在储存环中回旋的离子束与残余气体分子、内靶和冷却电子束相互作用时的损失机制及相应的束流寿命,针对兰州重离子加速器冷却储存环实验环内靶模式,计算了50—500MeV/u12C6+,36Ar18+,132Xe54+和238U92+等束流在各种损失机制影响下所对应的束流寿命和总的束流寿命。结果表明:影响束流寿命的主要因素是与内靶分子(原子)之间的电荷交换及与冷却电子束之间的辐射复合;对于重离子束132Xe54+和238U92+,与冷却电子束之间的辐射复合是影响其储存寿命的主要因素
基于DSP的磁场电源控制器软件设计
No full text为了使兰州重离子加速器冷却储存环的磁场电源控制器及时更新输出的波形数据,以TI公司的TM320C6713芯片为中央处理器,结合FPGA逻辑编程,采用双FIFO数据缓存机制和Aitken插值算法,编写并优化了磁场电源控制器软件系统。利用数据驱动模式的编程方式提高了系统的执行效率和可维护性。同时通过对更新的波形数据做Aitken插值运算,使其大小减少为原始数据的1/1024,提高了数据的传输和存储效率。经现场测试,本软件系统运行稳定可行,达到设计要求
核径迹膜断面SEM样品制备
No full text利用紫外光辐照结合液氮冷冻技术成功地制备了聚碳酸酯核径迹膜断面的扫描电子显微镜样品。结果表明,紫外光辐照引起了聚碳酸酯核径迹膜发生了光降解并使之脆化,导致其断裂伸长率大幅降低。经紫外光辐照过的核径迹膜在液氮中很容易被折断形成断面。扫描电子显微镜观测结果表明,形成的断面不存在残余形变,从而准确地表达了孔道的面分布、尺寸和形状等信息