2009年  第26卷  第4期

2009, 26(4): 275-281. doi: 10.11804/NuclPhysRev.26.04.275

2009, 26(4): 282-287. doi: 10.11804/NuclPhysRev.26.04.282

2009, 26(4): 288-293. doi: 10.11804/NuclPhysRev.26.04.288

2009, 26(4): 294-299. doi: 10.11804/NuclPhysRev.26.04.294

The study of the splittings between the masses of mesons with different spin and orbit quantum numbers is important for checking the quark potential model. In the previous calculations with quark potential models, the splitting between ηc and J/ψ is however too small to the experimental result. In this paper the mass splitting of ηcJ/ψ and the splitting between the new
meson ηb and Υ(1s) are investigated with the complete Breit quark potential regularized by applying the form factor μ2/(q2+μ2) one time in momentum space. In addition, because the complete Breit potential includes the spinorbit interaction, it can be used to investigate the splittings among χc0, χc1
and χc2. The investigated results indicate that the screen mass μ in the form factor of regularization is related to the reduced mass of meson.
The splittings of ηc-J/ψ, ηbΥ, and χc0χc1χc2 can reproduce the experimental results with high accuracy when the screen mass is expanded to the thirdorder polynomial of meson reduced mass.

2009, 26(4): 300-303. doi: 10.11804/NuclPhysRev.26.04.300

∈利用光滑粒子流体动力学模型，研究了NN=200 GeV Au+Au碰撞产生的介子发射源的视像结果。 碰撞后的演化图显示， 系统在演化过程中呈现出明显的非均匀性颗粒集团分布。 这种发射源所得到的视像分析结果表明， 即使在相同的碰撞参数下， 不同事件的相对发射源函数也会存在差异。 这种差异在大碰撞参数下表现得尤为明显。 We investigate the imaging of pionemitting source produced in NN=200 GeV Au+Au collisions with NeXSPheRIO model. The pictures of the system evolution show that there is obvious inhomogeneous structure of granular lumps. The results of imaging analysis indicate that the relative source functions for the various events of the granular sources are different even though the events are with the same impact parameter. This difference is more evident for the events with large impact parameter.
2009, 26(4): 304-307. doi: 10.11804/NuclPhysRev.26.04.304

2009, 26(4): 308-311. doi: 10.11804/NuclPhysRev.26.04.308

2009, 26(4): 312-318. doi: 10.11804/NuclPhysRev.26.04.312

236U是一种长寿命放射性核素， 其半衰期为T1/2=2.342(3)×107 a， 在自然界的含量极微， 天然铀中 236U/238U的原子比约为～10-14。 目前， 对于236U及其测量的研究报道较少。首先介绍了236U的产生， 并对地球中 236U的总量进行了估算。 概述了236U测定在亿年级中子注量率积分评估、 核环境和核活动监测， 以及地质学等领域中的重要应用。 最后，对国内外加速器质谱（AMS）测量236U的状况进行了综述，报道了中国原子能科学研究院AMS小组通过对同位素干扰鉴别的多方面研究， 初步建立了236UAMS测量方法。 236U is a longlived radionuclide with half life of 2.342(3)×107 a. The ratio of 236U/238U is about 10-14 in the natural Uranium. The origin and production of 236U in globe are introduced and estimated in this paper，respectively. The major applicationsion of 236U as a 100 million year neutron flux integrator，as a “fingerprint” for monitoring nuclear environment and nuclear activity，and as a tracer in geological studies are briefly summarized. The accelerator mass spectrometry(AMS) measurement of 236U in the world and the research on HI 13 tandem accelerator at China Institute of Atomic Energy(CIAE) is also mentioned in this paper.

2009, 26(4): 319-321. doi: 10.11804/NuclPhysRev.26.04.319

2009, 26(4): 322-326. doi: 10.11804/NuclPhysRev.26.04.322

2009, 26(4): 327-332. doi: 10.11804/NuclPhysRev.26.04.327

Characteristics of electrodeposited uranium films of uranium ore water sample in ammonium sulphate was investigated in this work. The optimized electrodeposited conditions were as follows： electrolyte was ammonium sulphate of 0.8 M， and current density at the cathode was 0.6 A/cm2， electrolyte pH value was 2.5， the time of plating on the electrodeposition was 1 h. In this situation， the uniform， thin and adheresive films were produced by electrodeposition method. Two samples were made， one electrodeposition of pure uranyl nitrate， and another electrodeposition of uranium ore water sample after chemical separation. Characteristics of electrodeposited uranium films of uranium ore water sample after chemical separation was studied， making comparisons with electrodeposited films of uranyl nitrate. The analysis of film characteristics was done through infrared (IR) spectrum， scanning electron microscopy(SEM)， element analysis and α spectrum measurment. According to Fourier transform infrared spectra， the asymmetric stretching vibration band of uranyl group is around 887 cm-1. In addition， according to IR spectrum， we know that uranium exists mainly as the form of hydrated polymeric compound in the film. Electrodeposited uranium films also included many NH+4. Polymeric structures of variable composition were present in the electrodeposited samples， with the unit monomeric formula UO2(OH)2·xNH3·yH2O or UO2(OH)2-x·(ONH4)x·yH2O. Scanning electron microscopy shows that the two samples have similar surface characteristics and no cluster is observed. The samples were also measured by spectrometer equipped with Passivated Implanted Planar Silicon(PIPS) detector. From the α spectrum， we know that isotopes of uranium in the film are 238U and 234U. 235U is not found in the α spectrum. It also shows that the chemical separation process can isolate uranium from other interfering elements effectively， the result of chemical separation is very satisfactory and electrodeposited process is rather efficient. Source electrodeposited in ammonium sulphate through optimized conditions satisfies the need of highresolution α spectrum.

2009, 26(4): 333-337. doi: 10.11804/NuclPhysRev.26.04.333

〗采用磁控溅射技术在Si衬底上沉积Si/$Fe(10 nm)/Nb(4 nm)/Fe(4 nm)/Nb(4 nm)$2/ $Fe(4 nm)/Nb(4 nm)$4多层膜。 用2 MeV的 Xe离子在室温下辐照多层膜。采用俄歇深度剖析、X射线衍射和振动样品磁强计分析辐照引起的多层膜元素分布、 结构及磁性变化。AES深度剖析谱显示当辐照注量达到1.0×1014 ions/cm2时， 多层膜界面两侧元素开始混合； 当辐照注量达到2.0×1016ions/cm2时， 多层膜层状结构消失， Fe层与Nb层几乎完全混合。XRD谱显示， 当辐照注量达到1.0×1014ions/cm2时， Nb的衍射峰和Fe的各衍射峰的峰位相对于标准卡片向小角方向偏移， 这说明辐照引起Nb基和Fe基FeNb固溶体相的形成；当辐照注量大于1.0×1015 ions/cm2时， 辐照引起非晶相的出现。 VSM测试显示，多层膜的磁性随着结构的变化而变化。 在此实验基础上， 对离子辐照引起界面混合现象的机理进行了探讨。The behavior of the metallic multilayers of Si/$Fe(10 nm)/Nb(4 nm)/Fe(4 nm)/ Nb(4 nm)$2/$Fe(4 nm)/Nb(4 nm)$4 under 2 MeV Xeion irradiation has been investigated by depth profile analysis of Auger electron spectroscopy，X ray diffraction and vibrating sample magnetometer. The obtained experimental results show that the intermixing between Fe and Nb layers occurs in the 1.0×1014 ions/cm2 irradiated multilayer sample which results in the formation of Nbbased and Febased FeNb solid solution. For the samples irradiated to fluence larger than 1.0×1014 ions/cm2， amorphisation is observed， and moreover， the layered structure of the multilayer samples is broken up completely for the samples under 1.0×1016 or 2.0×1016 ions/cm2 irradiation. Vibrating sample magnetometer measurement also reveals that the magnetization of the samples changes with the evolution of the structure of multilayers. Possible mechanism of the modification in Fe/Nb multilayers induced by Xeion irradiation is briefly discussed.

2009, 26(4): 338-342. doi: 10.11804/NuclPhysRev.26.04.338

2009, 26(4): 343-347. doi: 10.11804/NuclPhysRev.26.04.343

2009, 26(4): 348-351. doi: 10.11804/NuclPhysRev.26.04.348

For estimating the effect of low doses Xray continual irradiation to immunity system of mouse， BALB/c mice were continually irradiated to 1.03 Gy by X rays at a dose rate of 0.2 Gy/min in 13 d. At 24 or 48 h after irradiation， the immunocyte cycle and apoptosis were determined by flow cytometry， and the thymus and spleen weights were measured too. The results showed that the cycle of thymocyte were arrested in G2/M at 24 h， the number of peripheral blood lymphocytes and thymocytes in G0/G1 phase at 48 h was up and the percentage of apoptosis had a significance increase in both of time points； the cycle of spleen lymphocytes was delayed in G0/G1 at 24 h， in S phase at 48 h， the apoptosis had a significance decrase at 24 and 48 h； spleen index declined significantly at 48 h. The results suggested that low doses continual Xray wholebody irradiation could activate different cell cycle checkpoints， and result in some changes of apoptosis and some damages to immunocytes. The continual Xray irradiation affects the organs differently， it might provide experiment basis for radioprotection.

2009, 26(4): 352-355. doi: 10.11804/NuclPhysRev.26.04.352

Lowenergy heavy ion implantation is an organism mutation method developed in middle of 1980s, which has a potential application in breeding and radiation therapy. The dosesurvival curve is a characteristic effect in radiobiology. Implanted with lowenergy heavy ions, organisms could manifest a Saddlelike dosesurvival curve. In this article, the Saddlelike dosesurvival effect and its modeling has been described, and several topics in model simulation are discussed.

2009, 26(4): 356-359. doi: 10.11804/NuclPhysRev.26.04.356

2009, 26(4): 360-366. doi: 10.11804/NuclPhysRev.26.04.360