基于COM的HIRFL-CSR电源远程监控系统

本文介绍了兰州重离子加速器冷却储存环(HIRFL-CSR)最新改造后的电源远程监控的总体设计,包括硬件和软件方面的设计。该系统采用了COM组件实现前端服务器Oracle数据库与前端被控设备数据的交互,以及WEB服务器与中心Oracle数据库的数据交互,实现了控制人员对设备的远程监控。这样有利于对电源设备状态的实时监控,以及电源系统与各子系统的数据交互。该系统已经在现场经过测试,性能稳定。

电源远程控制中非线性误差的软件补偿

本文介绍应用MSC1210实现的HIRFL-CSR大科学工程束流注入线电源远程控制系统的实现原理及其中电源非线性部分远程给定与回读误差的软件补偿方法,从而提高了电源远程调节的读写误差,以满足HIRFL-CSR大科学工程对电源远程调节的高精度的要求。

离子注入/辐照引起Al_2O_3单晶的改性研究

600 K温度下用110 keV的He+,Ne+,Ar+离子注入及320 K温度下用230 MeV的208Pb27+辐照Al2O3单晶样品,研究了离子注入和辐照对Al2O3单晶样品结构和光学特性的影响。从测得的光致发光谱可以清楚地看到,所有样品在波长为375,413和450 nm处出现了强的发光峰,且所有5×1016ion/cm2注入样品的发光峰均最强。经过高能Pb辐照后的样品,在390 nm处出现了新的发光峰。透射电镜分析发现在注入氖样品100 nm入射深度以内形成了高浓度的小空洞(1—2 nm),在Ne沉积区域有少量大空洞形成。傅立叶变换红外光谱分析发现,波数在460—510 cm-1间的振动吸收带经过离子辐照后展宽,随着辐照量的增大,该振动吸收强度显著减弱。1 000—1 300 cm-1对应Al-O-Al桥氧伸缩振动模式的吸收带,辐照后向高波数方向移动。对离子注入和辐照对Al2O3单晶样品结构损伤机理进行了初步探讨。

Late Quaternary aeolian dust input variability on the Chinese Loess Plateau: inferences from unmixing of loess grain-size records

IEECAS SKLLQG

钻探揭示的青藏高原东北部黄土地层与第四纪气候变化

IEECAS SKLLQG

光谱和能级寿命自动测量控制系统设计

基于束箔光谱和能级寿命测量,建立了自动测量控制系统,着重介绍了系统的工作原理、总体设计和软件开发,最后给出了在线实验结果。

重离子注入质量沉积效应的研究动态

重离子注入生物学效应是我国首创的研究领域 ,但其基础理论研究开展较少 ,特别是在重离子束辐照所特有的电荷交换、动量传递和质量沉积效应等方面。前人多采用低能重离子束注入生物小分子和仪器分析手段来研究重离子注入质量沉积 ,但有关质量沉积对处于生命状态下的活生物体组织细胞和生物大分子所带来的生物学效应的研究还未见报道。本文作者首次提出应用稳定性和放射性重离子束注入细胞、生物大分子和抗生素等药物分子 ,然后用X 射线晶体衍射分析、微观和亚微观放射自显影、放射性测量和分子生物学等研究技术对重离子注入质量沉积和质量沉积效应开展进一步的研究

高增益负反馈的幅度稳定系统

从控制理论的角度对幅度稳定系统进行了研究 ,提出用黑箱办法 ,结合实验分析控制对象 ,确定其数学模型 ,并依此来设计控制器 ,以达到在保证环路稳定的基础上提高回路增益的目的

中能重离子碰撞中的局域平衡讨论

在ＢＵＵ框架下，讨论了中能重离子碰撞过程中的平衡过程，以及相关的物理量，如集体流、温度、化学势．研究发现，一定时间以后达到局域平衡，且中心区域最先达到平衡，同时周边碰撞时也发现存在局域平衡．平衡时温度为５一７ＭｅＶ．

Low-lying non-normal parity states in B-8 measured by proton elastic scattering on Be-7

A new measurement of proton resonance scattering on Be-7 was performed tip to the center-of-mass energy of 6.7 MeV using the low-energy RI beam facility CRIB (CNS Radioactive Ion Beam separator) at the Center for Nuclear Study of the University of Tokyo. The excitation function of Be-7 + p elastic scattering above 3.5 MeV was measured Successfully for the first time, providing important information about the resonance structure of the B-8 nucleus. The resonances are related to the reaction rate of Be-7(p.gamma)B-8. which is the key reaction in solar B-8 neutrino production. Evidence for the presence of two negative parity states is presented. One of them is a 2(-) state observed as a broad s-wave resonance, the existence of which had been questionable. Its possible effects on the determination of the astrophysical S-factor of Be-7(p.gamma)B-8 at solar energy are discussed. The other state had not been observed in previous measurements, and its spin and parity were determined as 1(-). (C) 2009 Elsevier B.V. All rights reserved.

Microelements in Potato and Lily Samples Studied by Laser-Induced Breakdown spectroscopy Technology

A LIBS setup was built in the Institute of Modern Physics. In our experiments, LIBS spectra produced by infrared radiation of Nd : YAG nanosecond laser with 100 and 150 mJ pulse energy, respectively, were measured by fiber optic spectrometer in the ranges of 230-430 run and 430-1080 nm with a delay time of 1.7 and gate width of 2 ms for potato and lily samples prepared by vacuum freeze-dried technique. The lines from different metal elements such as K, Ca, Na, Mg, Fe, Al, Mn and Ti, and nonmetal elements such as C, N, O and H, and some molecular spectra from C-2, CaO, and CN were identified according to their wavelengths. The relative content of the six microelements, Ca, Na, K, Fe, Al, and Mg in the samples were analyzed according to their representative line intensities. By comparison we found that there are higher relative content of Ca and Na in lily samples and higher relative content of Mg in potato samples. The experimental results showed that LIBS technique is a fast and effective means for measuring and comparing the contents of microelements in plant samples.

Pre-irradiation with low-dose C-12(6+) beam significantly enhances the efficacy of AdCMV-p53 gene therapy in human non-small lung cancer

The combination of ionizing radiation and gene therapy has been investigated. However, there are very few reports about the combination of heavy-ion irradiation and gene therapy. To determine if the pre-exposure to low-dose heavy ion beam enhances the suppression of AdCMV-p53 on non-small lung cancer (NSLC), the cells pre-irradiated or non-irradiated were infected with 20, 40 MOI of AdCMV-p53. Survival fraction and the relative biology effect (RBE) were determined by clonogenic assay. The results showed that the proportions of p53 positive cells in C-12(6+) beam induced AdCMV-p53 infected cells were more than 90%, which were significantly more than those in gamma-ray induced AdCMV-p53 infected cells. The pre-exposure to low-dose 12C6+ beam significantly prevented the G(0)/G(1) arrest and activated G(2)/M checkpoints. The pre-exposure to C-12(6+) beam significantly improved cell to apoptosis. RBEs for the C-12(6+)+ AdCMV-p53 infection groups were 30%-60%,20% -130% and 30%-70% more than those for the C-12(6+)_irradiated only, AdCMV-p53 infected only, and gamma-irradiation induced AdCMVp53 infected groups, respectively. The data suggested that the pre-exposure to low-dose C-12(6+) beam significantly promotes exogenous p53 expression in NSLC, and the suppression of AdCMV-p53 gene therapy on NSLC.

Production cross section of Th-236 in the interaction of U-238 with 60 MeV/u O-18 ions

The neutron-rich target-like isotope Th-236 has been produced in the U-238-2p multinucleon transfer reaction between a 60 MeV/u O-18 beam and natural U-238 targets. The activities of thorium were determined after radiochemical separation of Th from the mixture of uranium and reaction products. The Th-236 isotope was identified by the characteristic gamma-rays of 642.2, 687.6 and 229.6 keV. The production cross section of Th-236 was determined to be 250 +/- 50 mu b.