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2009年  第26卷  第4期

核物理
反转岛附近原子核奇特性质研究进展
支启军, 张小平
2009, 26(4): 275-281. doi: 10.11804/NuclPhysRev.26.04.275
摘要:
反转岛附近原子核奇特性质的研究是当前核物理研究的热点。 首先简要回顾和介绍了反转岛附近原子核奇特性质的实验进展, 然后介绍了对这些奇特核性质的理论研究进展。 主要包括相对论平均场模型、 壳模型、 HartreeFock模型和宏观微观模型在该区域的发展和研究结果。 重点介绍了宏观微观模型在反转岛附近原子核奇特性质研究中的进展。 此外, 还分析和比较了各种理论模型在描述反转岛附近原子核性质上取得的成功和模型之间的差异。
双奇核174Re中的准粒子形状驱动效应
郭松, 张玉虎, #, 周小红, 强赟华, 郭文涛, 郭应祥, 方永得
2009, 26(4): 282-287. doi: 10.11804/NuclPhysRev.26.04.282
摘要:
对双奇核174Re的在束γ谱学实验数据作了仔细分析, 提取出了带间与带内E2 γ跃迁分支比, 并导出了其约化跃迁概率的比值。用带混合理论对约化跃迁概率的比值进行了分析, 得到带间相互作用强度及转动带形变的信息。发现不同组态的转动带其跃迁电四极矩具有明显的差异。与相邻奇A核的结构特征类似,这种跃迁电四极矩的差异很可能是由于1/2-[541]准质子或1/2-[521] 准中子对原子核的形状驱动效应造成的。 By analyzing carefully the inbeam γ spectroscopy data of odd-odd 174Re, we have extracted the branching ratios of the interband and intraband E2 γ transitions from the two rotational bands of different configurations in 174Re.The ratios of the reduced transition probabilities B(E2) have been deduced and analyzed using a band mixing theory. Information on the band interaction and deformation have been obtained. Apparent differences of transition quadrupole moments are found in the two configurations. A likely reason for the differences in the transition quadrupole moments is the shape driving effects of 1/2-[541] quasiproton or 1/2-[521] quasi neutron, which has been proposed in the oddA neighbors of 174Re.
通过破裂反应研究轻丰中子核的集团结构
范凤英, 郑涛#, 叶沿林, 江栋兴, 华辉, 李智焕, 葛愉成, 史帆, 聂鹏煊
2009, 26(4): 288-293. doi: 10.11804/NuclPhysRev.26.04.288
摘要:
概括介绍了关于轻丰中子同位素链集团结构的理论模型和通过破裂反应研究该结构的实验方法、 实验装置及物理分析。 The theoretical models of the cluster structures of the light neutronrich nuclei as well as the corresponding physical mechanism and experimental approaches by breakup reaction have been introduced, which may serve as references for possible experimental studies of the cluster structure of light neutronrich nuclei. 
Breit势的正规化与ηc-J/ψ的劈裂
吉日木图
2009, 26(4): 294-299. doi: 10.11804/NuclPhysRev.26.04.294
摘要:
研究自旋和轨道量子数不同的介子之间的质量劈裂对检验夸克势模型非常重要。
在以往的夸克势模型计算中,ηc-J/ψ的质量劈裂都很难达到实验的值。 用正规化形状因子μ2/(q2+μ2), 在对完整的动量空间中的Breit夸克势实施一次正规化下研究了ηc-J/ψ和新介子ηb与Υ(1s)之间的质量劈裂。 结果表明, 正规化形状因子中的屏蔽质量μ应与介子折合
质量有关, 当将其展开为介子折合质量的三阶多项式时, 上述介子质量劈裂可以精确重现实验的结果。另外, 由于完整的Breit势包含有自旋-轨道耦合相互作用的项,因而还可以研究χc0,χc1和χc2之间的质量劈裂。
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.
对光滑粒子流体动力学模型π源的视像分析
任延宇, 高长晨, 杨志韬, 张卫宁, #
2009, 26(4): 300-303. doi: 10.11804/NuclPhysRev.26.04.300
摘要:
∈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.
带电线性谐振子在非对易空间中的Wigner函数
王亚辉, 任亚杰, 王剑华
2009, 26(4): 304-307. doi: 10.11804/NuclPhysRev.26.04.304
摘要:
在利用Wigner函数性质的基础上, 考虑到空间变量的对易关系中包含了坐标坐标的非对易性, 得到了带电线性谐振子在非对易空间中的Wigner函数。 Based on the property of wigner function, the Wigner function of charged Linear Harmonic Oscillator in noncommutative space was obtained by considering the noncommutative of the coordinatecoordinate in the relation of space variable.
加速器
HIRFL-CSR前端总线控制器的改进设计
赵龙, 乔卫民, #, 敬岚, 刘伍丰
2009, 26(4): 308-311. doi: 10.11804/NuclPhysRev.26.04.308
摘要:
论述了用于兰州重离子加速器冷却存储环(HIRFLCSR)控制系统的前端总线系统控制器的改进。 改进了控制器的嵌入式操作系统和应用程序, 开发了控制器和数据库交换数据的应用程序。 该控制器基于BGA封装的ARM920T(ARM9)处理器和嵌入式的LINUX操作系统, 可以连接标准的VGA显示器、 键盘、 鼠标, 采用了现场可编程的FPGA器件进行背板接口设计, 并具有64 mA高驱动能力的总线驱动器, 以及拥有灵活的接口信号定义可编程能力, 是HIRFLCSR控制系统的关键部件。 The EVME bus controller which is a key component of the HIRFLCSR control system was improved . Besides reconfiguring the embedded Linux, a utility program was developed for data exchange between the controller and the database. The bus controller is based on ARM920T(ARM9) micro processor which is BGA packaged. The bus controller has the universal interface of VGA display, keyboard, and mouse. The backboard interface logic is programmed in an insystem configurable FPGA device. The bus can drive high current up to 64 mA, with the flexibility of the programmable signal definitions. All the improved performance helped the EVME bus controller play a crucial role in HIRFLCSR control system.
核技术
236U及其加速器质谱(AMS)测量
王祥高, 何明, 李朝历, 王伟, 张大伟, 黄春堂, 石国柱, 沈洪涛, 吴绍雷, 贺国珠, 龚杰, 陆丽燕, 武绍勇, 姜山,
2009, 26(4): 312-318. doi: 10.11804/NuclPhysRev.26.04.312
摘要:
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.
RETGEM探测器的初步测试
刘 达, 鲁辰桂, 段利敏, #, 胡荣江, 鲁彦霞, 李祖玉, 张金霞, 胡正国, 孙友梅, 徐治国, 马朋, 耿朋, 唐述文, 杨贺润, 王文昕, 周建荣
2009, 26(4): 319-321. doi: 10.11804/NuclPhysRev.26.04.319
摘要:
研制了一种新型的带有阻抗性电极的TGEM——RETGEM(Thick GEM with Resistive Electrodes)探测器, 阻抗性电极可以有效地保护探测器和前端电子学免于偶尔放电的损伤。 对RETGEM探测器进行了初步测试, 其中包括计数率、能量分辨、增益以及打火率。 结果表明, 探测器达到了设计的基本要求。 In this study we present preliminary results from a new detector: a thick gaseous electron multiplier(GEM) with resistive electrodes. The resistive electrodes protect the detector and the frontend electronics from damage by occasional discharges. In different gas mixtures, we test Thick GEM with Resistive Electrodes(RETGEM) detector for the first time, including counting rate, energy resolution, effective gain, and discharge probability. The results can satisfy the basic demand of RETGEM detector design.
基于Micromegas探测技术的中子CT可行性研究(英文)
周健荣, 张毅, 汪珊珊, 胡碧涛, #
2009, 26(4): 322-326. doi: 10.11804/NuclPhysRev.26.04.322
摘要:
在培育新品种过程中能够实时掌握了解土壤中植物根系的形态以及其生长情况将为植物学家提供很多不可或缺的信息。对基于 micromegas 探测技术的中子 CT 在这一新应用的试验环境进行了仿真模拟, 通过三维图像重建后,得到了令人满意的预期结果。首先通过 Geant4 和 Garfield 模拟计算利用聚乙烯薄膜作为中子转换层的 micromegas 中子探测器, 得到了非常理想的位置分辨, 说明基于micromegas 探测技术建立中子 CT 照相系统的可行性。 然后利用MCNP仿真模拟14 MeV 中子CT 的实验环境, 最后由Matlab程序进行图像重建。In this paper, the possibility using micromegas(MicroMesh Gaseous Structure) as neutron detector in 14 MeV neutron computed tomography(CT) has been simulated. The results show that the micromegas neutron detector has high spatial resolution and is a good candidate for neutron radiography. The threedimensional images of plant roots in soil are successfully and clearly obtained by the 14 MeV neutron CT with micromegas as a neutron detector. In the present simulation, MCNP is employed for 14 MeV neutron transport in the sample and Matlab for the 3D photograph reconstruction.
铀矿坑水样中铀电沉积层的表征
李小飞, 秦芝, 张丽娜, 白静, 林茂盛, 雷富安, 丁华杰, 吴晓蕾, 郭俊盛
2009, 26(4): 327-332. doi: 10.11804/NuclPhysRev.26.04.327
摘要:
描述了硫酸铵溶液中铀矿坑水样品中铀的电沉积层特性。 电沉积液为10 ml 0.8 M的硫酸铵溶液, 电流密度0.6 A/cm2, pH值为2.5, 电镀1 h。 电沉积经化学分离后的水样品和电沉积的纯硝酸铀酰样品进行了比较, 并对二者分别做了红外(IR)光谱、 扫描电镜(SEM)、 元素分析以及α能谱测量。 IR谱上铀酰离子的反对称伸缩振动峰在887 cm-1附近, 使电沉积在不锈钢片上的铀主要以铀酰离子水合物的形式存在, 有一部分NH+4以NH3的形式替代水合物中的水, 使电沉积层中铀的化合物形式为UO2(OH)2·xNH3·yH2O或者UO2(OH)2-x·(ONH4)x·yH2O, 铀酰离子通过链的形式形成聚合结构。 SEM照片显示电沉积层均匀, 没堆积成团现象出现。 α谱表明电沉积层中铀的同位素主要是238U和234U, 相应的α能量峰4198和4773 keV很显著, 没其它峰的干扰。
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.
交叉学科
Fe/Nb多层膜中离子辐照效应研究(英文)
魏孔芳, 王志光, #, 孙建荣, 臧航, 姚存峰, 盛彦斌, 马艺准, 缑洁, 卢子伟, 申铁龙, 杨成绍,
2009, 26(4): 333-337. doi: 10.11804/NuclPhysRev.26.04.333
摘要:
〗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.
高压条件下高能重离子辐照材料研究进展
翟鹏飞, 刘杰, 孙友梅, 侯明东, 段敬来
2009, 26(4): 338-342. doi: 10.11804/NuclPhysRev.26.04.338
摘要:
高能重离子辐照处于高压条件下材料的研究,是随着高能重离子加速器技术的快速发展而出现的一个新的研究领域, 研究结果涉及材料学、 地质学、地质年代学、核废料处理学等学科。简要介绍最近几年国内外在高能重离子辐照高压条件下材料研究领域的研究现状及已取得的结果,并对未来在兰州重离子加速器冷却储存环(HIRFLCSR)上开展相关研究工作的前景作了展望。With development of high energy heavy ion accelerator, it is possible to perform heavy ion irradiation experiments of pressurized materials in diamond anvil cells(DACs). It is a new research field. The results expected from irradiation experiments under high pressure will have impacts on several scientific fields such as materials science,geoscience,geochronology,and nuclear waste storage. In this paper, some of recent works in this field are presented and reviewed. Furthermore,the research plan of materials under high pressure based on HIRFL-CSR is introduced.
低频电磁辐射与脑神经细胞微管的相互作用
高峰, 肖德涛, 张登玉, 周熠
2009, 26(4): 343-347. doi: 10.11804/NuclPhysRev.26.04.343
摘要:
研究了低频电磁辐射场与脑神经系统的相互作用规律及其机理。电磁辐射为非电离低频电磁场, 将脑神经细胞骨架微管(MT)中的两态物理系统进行量子化,用密度矩阵描述脑神经系统中信息位的状态, 建立并求解脑神经系统中信息位的动力学方程。 结果表明: 当非电离低频电磁辐射射向大脑时, 脑神经系统中信息位的密度矩阵非对角元在任意时刻都不为零, 能够保持较好的量子相干性, 脑神经系统的功能不会受到破坏。
低剂量连续辐射引起的小鼠免疫系统的变化
谢漪, 张红, #, 党秉荣, 郝冀芳, 王小虎
2009, 26(4): 348-351. doi: 10.11804/NuclPhysRev.26.04.348
摘要:
为了评估低剂量X射线连续辐射对BALB/c小鼠健康机体免疫系统的影响, 实验采用X射线全身连续照射BALB/c小鼠, 照射第一天剂量为0.07 Gy, 剂量率0.2 Gy/min, 之后每天照射0.08 Gy, 共照射12 d, 累积剂量1.03 Gy, 照射后24和48 h取血、胸腺和脾脏。 流式细胞仪检测免疫细胞周期和凋亡的变化, 胸腺和脾脏指数用重量法获取。 实验结果表明, 小鼠胸腺细胞的周期在照射后24 h被阻滞在G2/M期; 外周血淋巴和胸腺细胞周期48 h被阻滞在 G0/G1期, 细胞凋亡比例在照射后两个时间点都显著增加; 脾脏淋巴细胞周期24 h被阻滞在 G0/G1期, 48 h被阻滞在 S期, 细胞凋亡比例在24和48 h显著减少; 脾脏指数在照射后48 h显著减少。 故低剂量X射线连续全身照射BALB/c小鼠可激活免疫细胞不同的周期监测点, 引起免疫细胞凋亡比例发生变化, 造成一定的辐射损伤, 且这种影响随着免疫器官的不同而不同。
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.
低能重离子剂量-存活率效应及其拟合模型探讨
韩荣飞, 吴跃进, 卞坡, 王荣富, #
2009, 26(4): 352-355. doi: 10.11804/NuclPhysRev.26.04.352
摘要:
低能重离子注入生物体是20世纪80年代中期发展起来的一种诱变手段, 在诱变育种和放射医学等领域有巨大的应用前景。 物理辐照的剂量与存活率之间的关系是辐射生物学效应的最重要的关系之一, 低能离子与生物体相互作用的剂量存活率曲线表现为特殊的马鞍型。 介绍了低能重离子的马鞍型剂量存活率效应及其数学模型, 并探讨了模型拟合中存在的一些问题。
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.
严和店窑汝瓷和钧台窑钧官瓷的EDXRF分析
温昶, 赵会仙, 李融武, 李国霞, #, 郭培育, 高正耀, 赵维娟, 孙洪巍, 郭敏, 谢建忠
2009, 26(4): 356-359. doi: 10.11804/NuclPhysRev.26.04.356
摘要:
采用能量色散X射线荧光(EDXRF)技术测试了若干严和店窑汝瓷和钧台窑钧官瓷样品胎和釉的化学组成, 利用多元统计中的因子分析方法分析了两窑场胎和釉的差异。结果表明:严和店窑汝瓷和钧台窑钧官瓷能较好地加以区分。再次证明了钧瓷和汝瓷是有区别的。 The chemical components of the body and glaze samples of some Ru porcelains from Yanhedian kiln and Jun official porcelains from Juntai kiln are determined by the technology of Energy Dispersive Xray Fluorescence(EDXRF) in this work. The difference of the two kiln’s glaze and body are analyzed by factor analysis method of Multidimensional statistical analysis. The results indicate that Yanhedian Ru porcelains can be well distinguished from Jun official porcelains from Juntai kiln. This evidence once again proves that Jun ceramics and Ru ceramics can be distinguished obviously.
核能与核数据
238U(n,f)短寿命产物核累积产额的评价(英文)
郑娜, 陈忠靖, 孙吉宁, 刘廷进, 陈金象, 樊铁栓, #
2009, 26(4): 360-366. doi: 10.11804/NuclPhysRev.26.04.360
摘要:
为满足堆内或核爆中链式反应过程的燃耗值的计算需要,对裂变谱中子和14MeV中子诱发238U裂变的短寿命产物核的累积产额进行了评价。评价利用了所有可利用的实验数据, 经物理分析后, 使用AVERAGE程序加权平均, 用ZOTT程序进行同时评价, 给出了所要求能点的唯一最佳推荐数据, 并将评价结果与ENDF/B-VII, JEF-2.2, JENDL-3.2和CENDL-2的推荐数据进行了比较。 评价结果将用于CENDL-2的更新与升级。For reliable and consistent nuclear calculation, the cumulative yields for shortlived fission products are evaluated based on the available experimental data for 238U fission induced by fission spectrum neutrons and ~14 MeV neutrons. The data are processed using codes AVERAGE for weighed average and ZOOT for simultaneous evaluation. The evaluated data are compared with those in the major international nuclear data libraries, including ENDF/B-VII, JEF-2.2, JENDL-3.2 and CENDL-2. The present evaluation will be used to improve and update the CENDL-2 library.