低剂量辐射诱导hep G2细胞克隆存活和细胞周期适应性反应

以低剂量γ射线(0.05Gy)预照射人肝癌细胞hepG2,8h后再用高剂量(3Gy)照射,测定了细胞的克隆存活率和细胞周期。结果表明,低剂量辐射预处理可诱导hepG2细胞产生克隆存活适应性反应,并且有助于细胞通过G2/M期阻滞;低剂量辐射诱导的克隆存活适应性反应与增强的通过细胞周期阻滞的能力之间有一定的相关性。

低能离子注入小麦种子胚内的射程分布

采用110keV56Fe1+离子束垂直注入小麦种胚后,将小麦沿腹面的纵沟掰开,形成剖面,将剖面水平朝上粘贴在金属铜托上,用扫描电镜在剖面上从胚表面向纵深进行点分析,测定不同深度上由Fe元素激发出的特征X射线强度,由此得到了该种离子注入小麦胚内的最大射程约5μm,最可几射程为0.935μm.并对这种低能离子注入作物种子能诱发突变的机理进行了详细讨论.

Profibus现场总线技术的应用

将PROFIBUS现场总线技术成功应用于重离子加速器高频发射机控制系统中，达到了在强电磁干扰环境下系统稳定运行的要求。应用PLC控制设备和STEP7软件编程，采用分布式I/O模式，降低了系统调试和布线难度，缩短了开发周期，并为控制系统扩展提供灵活性。

用于光谱和能级寿命测量的控制及数据获取电子学系统

简要介绍了为高电离态原子光谱学实验研究装置研制的控制及数据获取电子学系统。该系统主要用于光谱和能级寿命的测量控制与数据获取。

单电离态Kr原子的能级寿命的研究

在 12 0keV的能量下 ,用束 -箔方法研究了跃迁强谱线的单电离态Kr原子激发态能级5p4 D07/2 ,5p4 D05/2 的寿命。并与理论和其它实验结果做了比较和讨论。

Kinetic energies of C-n(+) (n <= 58) fragment ions produced by nanosecond laser impact on C-60

Laser-induced fragmentation of C-60 has been studied using a time-of-flight mass spectrometric technique. The average kinetic energies of fragment ions C-n(+) (n <= 58) have been extracted from the measured full width at half maximum (FWHM) of ion beam profiles. The primary formation mechanism of small fragment ion C-n(+) (n < 30) is assumed to be a two-step fragmentation process: C60 sequential decay to unstable C-30(+) ion and the binary fission of C-30(+). Considering a second photo absorption process in the later part of laser pulse duration, good agreement is achieved between experiment and theoretical description of photoion formation. (C) 2009 Elsevier B. V. All rights reserved.

Shell-model Hamiltonian from self-consistent mean-field model: N = Z nuclei

We propose a procedure to determine the effective nuclear shell-model Hamiltonian in a truncated space from a self-consistent mean-field model, e.g., the Skyrme model. The parameters of pairing plus quadrupole-quadrupole interaction with monopole force are obtained so that the potential energy surface of the Skyrme Hartree-Fock + BCS calculation is reproduced. We test our method for N = Z nuclei in the fpg- and sd-shell regions. It is shown that the calculated energy spectra with these parameters are in a good agreement with experimental data, in which the importance of the monopole interaction is discussed. This method may represent a practical way of defining the Hamiltonian for general shell-model calculations. (C) 2009 Elsevier B.V. All rights reserved.

Photon emission from a chemically non-equilibrated parton gas at finite baryon density

We study hard photon production from a chemically non-equilibrated quark-gluon plasma with finite baryon density on the basis of Juttner distribution of partons of the system. We find that the photon production is ruled by early times, main contributions are given by rapidities y <= 6, and photon yield is a strongly increasing function of the initial quark chemical potential. In addition, we note that contribution from bremsstrahlung and Compton process qg -> q gamma dominates.

Development of multi-channel gated integrator and PXI-DAQ system for nuclear detector arrays

A multi-channel gated integrator and PXI based data acquisition system have been developed for nuclear detector arrays with hundreds of detector units. The multi-channel gated integrator can be controlled by a programmable Cl controller. The PXI-DAQ system consists of NI PXI-1033 chassis with several PXI-DAQ cards. The system software has a user-friendly GUI which is written in C language using LabWindows/CVI under Windows XP operating system. The performance of the PXI-DAQ system is very reliable and capable of handling event rate up to 40 kHz. (C) 2010 Elsevier B.V. All rights reserved.