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2005年  第22卷  第1期

放射性核束物理和核天体物理
晕核6He(25 MeV/u)的单、双中子转移截面测量
叶沿林, 庞丹阳, 葛愉成, 江栋兴, 郑涛, 王全进, 李智焕, 李湘庆, 艾颖, 张高龙, 王佳, 陈志强, 胡青元, A.Ozawa, Y. Yamaguchi, C. Wu, R. Kanungo, D. Fang, I. Tanihata
2005, 22(1): 1-2. doi: 10.11804/NuclPhysRev.22.01.001
摘要:
实验测量了25 MeV/u 的6He+9Be反应中的单、双中子转移微分截面. 利用反应耦合道模型初步分析了实验数据, 计算大体重现截面值. 转移反应对末态有相当的选择性, 并且双中子转移截面主要来自到基态的一步过程. 后角度截面的上升可能与连续态的耦合有关. Differential cross sections for quasi elastic scattering at forward angles and for 1n and 2n transfer reaction at backward angles induced by 6He at 25 MeV/u from 9Be target were measured. The experimental data were analyzed in the framework of the CRC model. The raise at backward angle of the 1n and 2n transfer cross section can not reproduced by the current calculation.
晕核6He(25 MeV/u)在9Be上的破裂反应
王佳, 叶沿林, #, 江栋兴, 郑涛, 王全进, 李智焕, 李湘庆, 张高龙, 庞丹阳, 吴翠娥, 陈志强, 胡青元, A.Ozawa, Y.Yamaguchi, R.Kanungo, D.Fang, I.Tanihata
2005, 22(1): 3-5. doi: 10.11804/NuclPhysRev.22.01.003
摘要:
25 MeV/u 6He+9Be反应的实验中利用多个探测器望远镜对反应产物进行了测量, 对实验中各个角度测量到的4He进行观察, 将其中两个有高能峰成分的探测器划分成三部分, 得到不同角度4He的单举能谱和破裂产生4He的微分截面. Different products of 6He nuclei from 9Be target has been measured with a 6He beam at energy of 25 MeV/u. The energy spectra at different angles for 4He isotope were analyzed and the experiment differential cross sections for the direct breakup reaction were obtained.


晕核6He(25 MeV/u)在9Be上的弹性散射研究
庞丹阳, 叶沿林, 江栋兴, 郑涛, 王全进, 李智焕, 李湘庆, 陈志强, 胡青元, 张高龙, 王佳, A.Ozawa, Y. Yamaguchi, C. Wu, R. Kanungo, D. Fang, I. Tanihata
2005, 22(1): 6-10. doi: 10.11804/NuclPhysRev.22.01.006
摘要:
分析了北京大学核物理实验小组在日本RIKEN实验室完成的25 MeV/u 6He和9Be的弹性散射实验数据,得到了弹性散射微分截面角分布. 利用双折叠模型,并通过拟合弹性散射微分截面得到了此弹靶体系在此能量下的弹性散射光学势. We analyzed the 6He elasticscattering from 9Be target at 25 MeV/u. A CenterofBeam (CB) method was used to calibrate the particletracking detectors and set the reference system of the detection system. The doublefolding model approach was used to calculate the real part of the optical model potential. The preliminary optical model potential parameters were extracted by fitting the experimental differential elasticscattering crosssections.
镜像核13N-13C 和15N-15O中的激发态晕或皮(英文)
陈金根, 蔡翔舟, 沈文庆, 马余刚, 任中洲, 蒋潍舟, 钟晨, 魏义彬, 郭威, 周星飞, 马国亮, 王鲲
2005, 22(1): 11-16. doi: 10.11804/NuclPhysRev.22.01.011
摘要:
用非线性相对论平均场对两对镜像核13N-13C 和15N-15O进行了研究. 发现无论在基态还是激发态, 用两套参数所得的结合能都跟实验值很接近. 计算结果显示13N的第一激发态(2s1/2)和第三激发态(1d5/2)各存在一个非束缚的质子晕, 而13C的第三激发态(1d5/2)存在一个弱束缚的中子皮. 另外研究表明, 在另一对镜像核15N-15O的第二激发态(2s1/2)和第一激发态(2s1/2)分别存在一个中子晕和质子皮. Properties of two pairs of mirror nuclei 13N-13C and15N-15O are investigated by using the nonlinear relativistic meanfield theory. It is found that all the calculated binding energies with two different parameter sets are very close to the experimental ones for both the ground states and the excited states. The calculations show that the first excited state (2s1/2) and the third excited state (1d5/2) in 13N are both unbound resonances with proton halo structure, whereas the third excited state (1d5/2) in 13C is weakly bound with a neutron skin. It is also predicted that there has a proton halo in the second excited state (2s1/2) of 15N as well as a neutron skin in the first excited state (2s1/2) of 15O.
17C反应截面的测量及其密度分布分析
吴翠娥, Yamaguchi Y, Ozawa A, Tanihata I, 叶沿林
2005, 22(1): 17-19. doi: 10.11804/NuclPhysRev.22.01.017
摘要:
在日本理化学研究所的放射性束流线上用透射法测量了能量为79 MeV/u的17C在12C反应靶上的反应截面;利用有限力程Glauber模型对17C的密度分布进行了分析. 同时拟合本实验结果及高能区的实验数据发现, 17C的中子密度分布中存在一个尾巴. 基于芯核加单粒子密度分布的假设,认为17C的价中子主要处于1d5/2轨道. We have measured the reaction cross section of 17C on a 12C target at 79 MeV/u using the transmission method. Together with previous data at high energy, we deduced the density distribution of 17C by fitting the experimental data using the finiterange Glauber model.
The analysis shows that a simple harmonicoscillator (HO) density is not adequate to explain consistently the present experimental data and the one at high energy simultaneously. To get a better fit of both the data, the existence of a tail in the density distribution of 17C is proposed. Based on the assumption of a core plus a single neutron, it is found that the valence neutron of 17C is mostly in the dorbital. This is in agreement with the conclusion from the measured momentum distribution.
大爆炸核合成相关的8Li(d,p)9Li反应截面测量
李志宏, 柳卫平, 白希祥, 郭冰, 连钢, 颜胜权, 王宝祥, 陆昀, 曾晟, 苏俊
2005, 22(1): 20-22. doi: 10.11804/NuclPhysRev.22.01.020
摘要:
利用8Li次级束测量了质心系能量7.8 MeV2H(8Li, 9Li)1H反应的角分布,导出了8Li(d, p)9Li反应的天体物理S因子及9Li→8Li+n虚衰变的渐近归一化系数. We have measured the angular distribution of 2H(8Li,9Li)1H at Ecm= 7.8 MeV and deduced the astrophysical Sfactor of 8Li(d, p)9Li reaction as well as the Asymptotic Normalization Coefficient (ANC) for 9Li → 8Li+n virtual decay.
两种计算旋转中子星性质方法的比较(英文)
文德华, 陈伟, 刘良钢
2005, 22(1): 23-26. doi: 10.11804/NuclPhysRev.22.01.023
摘要:
对两种基于广义相对论的计算旋转中子星性质的数值方法:Hartle法和Butterworth 和Ipser法(简记为BI法)进行了较详细的介绍、讨论和比较。对基于不同物态方程给出的旋转中子星的性质进行对比,结果表明两种方法给出的相关结果例如旋转中子星的质量、半径和形变等基本一致,特别是在观测值范围内的计算等均能较好地解释观测结果.
中子皮厚度与中子星半径
李俊, 沈刚, G. C. Hillhouse, 孟杰, #
2005, 22(1): 27-28. doi: 10.11804/NuclPhysRev.22.01.027
摘要:
在相对论平均场理论框架下在拉氏量密度中引入同位旋相关的高阶修正项, 研究了中子皮厚度和中子星半径的关系. 利用有效相互作用PK1得到208Pb的中子皮厚度最小可达0.17 fm, 这与近期SkyrmeHF模型得到的结果一致. 随着同位旋相关的高阶修正项系数的变化, 208Pb的中子皮厚度和中子星半径的变化趋势相同.
By adding isospin dependent high order correction ferms to existing relativistic mean field models.tlle thickness of neuron.skin in 208Pb and the radius of 1
.4 solar mass neutron star are studied.The effecfive interaction PK1 would lead the thickness of neutron-skin to a minimum of 0.17 fm which agrees with the analysis from Skyrme‘HF models. The coupling constants of the isospin dependent high order corection terms tend to change,the thickness of neutron-skin and the radius of neutron stars chan ge simultaneously.
利用密度相关的相对论平均场理论对核物质与中子星的研究(英文)
班淑芳, 李俊, 张双全, 贾焕玉, 桑建平, 孟杰, #
2005, 22(1): 29-31. doi: 10.11804/NuclPhysRev.22.01.029
摘要:
研究和详细地比较了RMF理论中不同的有效相互作用强度的密度依赖性, 并且讨论了这种密度依赖性对于核物质和中子星性质的影响. 对于核物质, 不同的参数组给出的对称核物质的饱和点非常接近, 基本都在经验值的范围内. 对于中子星, 考虑超子后不同参数组给出的质量极限的范围为1.52—2.06 M☉, 半径为10.24—11.38 km.
The density dependencies of various effective interaction strengths in the relativistic mean field and their influences on the properties of nuclear matter and neutron stars are studied and carefully compared. The differences of saturation properties given by various effective interactions are subtle in symmetric nuclear matter. The OppenheimerVolkoff mass limits of neutron stars calculated from different equations of state are 1.52—2.06 M☉, and the radii are 10.24—11.38 km with hyperons included.
核物质的对称能与中子皮厚度(英文)
沈刚, 李俊, HillhouseG.C, 孟杰, #
2005, 22(1): 32-33. doi: 10.11804/NuclPhysRev.22.01.032
摘要:
在现有的平均场模型中引入同位旋相关的高阶修正项.研究了核物质对称能的密度依赖性和。^208Pb的中子皮厚度。采用新提出的PK1相互作用以及NL3.S271和Z271相互作用.得到核物质饱和点对称能的范围为29-38MeV以及相应的^208Pb中子皮厚度为0.17—0.28fm.在所有相互作用中,核物质饱和点的对称能与^208Pb的中子皮厚度近似呈线性关系。
After adding isospin dependent high order correction terms to existing relativistic mean field models (RMF), the density dependence of symmetry energy and the neutron skin thickness S for 208Pb are studied. Using the new effective interaction PK1, together with NL3, S271 and Z271, a range of 29—38 MeV for the symmetry energy for nuclear matter at saturation point and the corresponding neutron skin thickness S = 0.14—0.28 fm for 208Pb are obtained. For all effective interactions, a linear relation between the symmetry energy at saturation point and the neutron skin thickness for 208Pb is observed.
元素指定是鉴别重丰中子核的重要手段
徐岩冰, 袁双责, 杨维凡, 丁华杰, 牛雁宁
2005, 22(1): 34-35. doi: 10.11804/NuclPhysRev.22.01.034
摘要:
简单地介绍了远离β-稳定线重质量丰中子核的合成和研究的科学意义,报告了元素指定对远离β-稳定线重丰中子核研究的重要作用.The significance of the synthesis and study of heavy neutron-rich nuclides far from β-stability is briefly introduced. The important role of element assignment for studying heavy neutron-rich nuclides far from β-stability is reported.
新同位素265Bh(Z=107)的合成证据
甘再国, 郭俊盛, 吴晓蕾, 范红梅, 秦芝, 雷祥国, 董成富, 徐华根, 陈若富, 张福明, 郭斌, 刘洪业, 王华磊, 谢成营, 冯兆庆, 郑勇, 宋立涛, 骆鹏, 徐瑚珊, 周小红, 靳根明, 任中洲
2005, 22(1): 36-38. doi: 10.11804/NuclPhysRev.22.01.036
摘要:
利用兰州重离子加速器提供的26Mg离子束轰击243Am靶, 产生了新同位素265Bh. 实验中用氦喷技术对产物进行传输, 并用一套具有数对探测器组的转轮收集探测系统对产物进行收集和测量. 通过观测265Bh与它的衰变子核261Db及257Lr之间的α衰变的关联, 实现了对新核素的鉴别. 实验测得265Bh的α衰变能量为(9.24±0.05) MeV, 半衰期为0.94+0.70 –0.31 s.New isotope ~(265)Bh(Z=107) was produced in bombardment of an ~(243)Am target with 135 MeV ~(26)Mg ions at HIRFL. Identification was made by observation of correlated α-particle decays between the new isotope ~(265)Bh and its ~(261)Db and ~(257)Lr daughters with four pairs of detectors. The experimental results show that the half-life of ~(265)Bh is 0.94~(+0.70)_(-0.31) s and its α energy is (9.24±0.05) MeV.
核技术应用
质子与重离子肿瘤治疗的进展
李文建
2005, 22(1): 39-43. doi: 10.11804/NuclPhysRev.22.01.039
摘要:
简要介绍了质子与重离子肿瘤治疗的历史和现状.现在,全世界有质子治疗中心23家,治疗肿瘤患者总数为39 612人;重离子治疗设备有3台,治疗肿瘤患者4 511人(包括He离子治疗2 054例病人).
肿瘤治疗的重离子束物理性质研究
党秉荣, 李文建, 马秋峰, 李强, 周光明, 王菊芳, 郝冀芳
2005, 22(1): 44-46. doi: 10.11804/NuclPhysRev.22.01.044
摘要:
重离子在肿瘤治疗方面的优势主要是由于其优越的物理性质,因此,研究其与生物体相互作用也就成为肿瘤治疗中的基本课题,介绍一些研究结果来解决人们关心的问题.
The advance of tumor therapy with heavy ions beam is due to the physics quality of heavy ions.So,the investigation of heavy ions action with biological materials will be a basic task. In the paper, the investigated results show a picture to resolve some problems which attract people's attention.
碳纳米管的离子束焊接研究
王震遐, 余礼平, 张伟, #, 孙立涛, 韩家广, 朱志远, 何国伟, 陈一, 胡岗
2005, 22(1): 47-79. doi: 10.11804/NuclPhysRev.22.01.047
摘要:
用C+离子束轰击多壁碳纳米管后, 发现了大量的由无定形碳纳米线组成的连接结构. 这种用高分辨透射电子显微镜和电子衍射分析确认的离子束焊接方法, 不但可以作为准备纳米电子(光子)学器件和线路的手段, 结合微操纵技术, 也有可能对其它系统器件排布的制作有所贡献.
石墨和纳米碳中缺陷和电子动量的研究
邓文, 周银娥, 祝莹莹, 黄宇阳, 刘起秀, 熊良钺
2005, 22(1): 50-53. doi: 10.11804/NuclPhysRev.22.01.050
摘要:
用正电子湮没技术研究了石墨和纳米碳中的缺陷和电子动量. 结果表明, 纳米碳中缺陷的开空间和缺陷浓度分别大于和高于石墨晶体. 纳米碳中存在开空间小于单空位的自由体积以及开空间相当于约10个空位聚集体的微孔洞. 石墨晶体中的自由电子动量分布表现出显著的各向异性: 沿石墨晶体的\[0 001\]晶向的自由电子(即2Pz电子)的动量最大; 偏离该方向越大, 自由电子的动量越小; 垂直于\[0 001\]晶向的自由电子的动量最小. 而纳米碳中自由电子动量的分布表现出各向同性. The defects and electronic momenta in graphite and nanocrystalline carbon have been studied by positron annihilation techniques. The results show that the concentration and open volume of defects in nanocrystalline carbon are higher/larger than that in graphite. Two kinds of microdefects were found in the nanocrystalline carbon: free volume (with a size of smaller than that of a monovacancy) and microvoids (with a size of about ten monovacancies). The anisotropic distribution of electronic momentum was found in single crystalline graphite, the momentum of free electron shows a maximum value in \[0001\] direction, and decreases with the increase of the angle deviation from \[0001\] direction and then reaches a minimum value in the direction perpendicular to \[0001\]. However, this phenomenon was not found in nanocrystalline carbon since the distribution of electronic momentum is isotropic.
LaFeO3纳米材料电四极超精细相互作用TDPAC测量
杜恩鹏, 葛智刚, 郑永男, 周冬梅, 左翼, 袁大庆, 王平生, 段晓, 石海松, 王建波, 李发伸, 朱升云
2005, 22(1): 54-57. doi: 10.11804/NuclPhysRev.22.01.054
摘要:
用时间微分扰动角关联方法测量了LaFeO3纳米中的电四极超精细相互作用. 扰动角关联探针核14057La14058Ce由139La(n,γ)140La反应产生, 实验只观察到一个La晶位的四极相互作用. 在室温下, 20和40 nm 以及晶体LaFeO3的四极相互作用频率ω0分别为 687.4 , 698.3 和742.9 Mrad/s , 频率分布宽度系数σ分别为 0.014, 0.009和0.001, 电场梯度不对称系数η=0. 实验数据表明, 电场梯度主轴与晶轴方向一致; 样品具有菱方结构, 晶体到纳米发生菱方向正交结构转变, 纳米尺度越小, 越趋于正交结构; 由于邻近核的扰动, 随纳米颗粒增大, 四极相互作用频率分布宽度系数σ变小, 晶体时最小.
The quadrupole interactions in the nanoand crystalline LaFeO3 perovskites have been investigated by TDPAC. The TDPAC probing nuclei 14057La14058Ce were produced through the nuclear reaction 139La(n.γ)140La at the CIAE heavy water experimental reactor. One electric quadrupole interaction was detected for each material, which is assigned to the La site. The quadrupole interaction frequencies of 687.4, 698.3 and 742.9 Mrad/s with a distribution coefficient of 0.014, 0.009 and 0.001 were observed at room temperature for the 20 and 40 nm nanoLaFeO3 and crystalline LaFeO3, respectively. The fitting yielded the EFG asymmetry parameter η=0, which indicates that the principal axes of the EFG is aligned with the crystallographic axes. The experimental results show that the structure of crystalline LaFeO3 is rhombohedral, the changing of the structure towards the orthorhombic structure takes place from the crystalline LaFeO3 to the nanoLaFeO3, and the smaller the nanograin size, the larger the change. The frequency distribution is caused by the perturbation of the neighboring atoms, and thus, the distribution coefficient increases with decreasing the nanograin size and the crystalline LaFeO3 arrives at its maximum.
Z-pinch中PF腔中子发射的产生机制
郭洪生, 何锡钧, 彭太平
2005, 22(1): 58-60. doi: 10.11804/NuclPhysRev.22.01.058
摘要:
采用束靶机制和热核机制,利用Maxwell分布,推导了等离子体焦点装置的中子产生机制、热核反应速率、中子平均能量及中子反映速率.Using the machanism of beamtarget and heatnuclics, the scaling relationship between the neutron yields of denser plasma focus and the PF plasma current is induced.The results of DPF .The principle is brief discussed with denser plasma focus(DPF) as the neutron generator.We have stated that some factors that influnce the DPF discharging to produce neutron yield and some methodsthat improve stability of neutron yields on the denser plasma focus(DPF).
采用数学分析方法分析样品核素含量的方法研究
郭洪生, 何锡钧, 彭太平, 杨高照, 王文川, 冯春
2005, 22(1): 61-63. doi: 10.11804/NuclPhysRev.22.01.061
摘要:
当样品含有多种能量的γ射线时,某一峰下的面积,不仅记录了该能量的光电效应事件,而且还包括了更高能量γ射线的Compton 散射事件。这样,就不能由峰下面积确定相应的γ射线强度,采用逆矩阵法对γ能谱进行分析可得到较好非结果。When the sample contains many kinds of energies γrays,their peak’s area not only records the matters of opticalelectronic effect but also the Compton scattering matters with higher energyγrays.So that,theγrays intensity conducted by the peak’s area can’t gain.Using the anti-matrix method,the better results of anlyze on theγSpectrometry may be getten.
近距离n, γ混合脉冲辐射场中γ辐射探测技术
胡孟春, 叶文英, 唐章奎, 王振通, 周殿忠, 张建华, 李忠宝
2005, 22(1): 64-66. doi: 10.11804/NuclPhysRev.22.01.064
摘要:
n, γ混合脉冲辐射场中, 在近距离、辐射强度低且中子辐射峰值比被测γ辐射峰值强度高的情况下, 传统γ辐射探测技术实施起来面临困难. 对PbWO4和CeF3等近年国内新研制的无机闪烁体进行了系列研究, 使用CeF3分别配光电倍增管和光电管,组合出了对γ辐射灵敏度高, 对中子相对不灵敏, 同时脉冲响应也快的光电探测系统, 应用以此为基础的探测技术在近距离n, γ混合脉冲辐射场中, 可将脉冲γ辐射探测信噪比提高一个量级以上.
It is difficult to detect low intensity γ radiation by using traditional γ radiation detection technique in a close distance n, γ commix pulse radiation field with very high intensity neutron radiation. PbWO4 and CeF3 which are newly developed inorganic scintillator in our country have been studied. Photoelectricity detector systemes which have high γ sensitivity and relative insensitive to neutron and fast time response were assembled by using CeF3 and photomultiplier tube. The ratio of signaltonoise for γ ray detection can be up to more than 10 times in close distance n, γ commix pulse radiation field by using this detector system.
C/O能谱测井非弹谱的解析方法软件及应用
庞巨丰, 李敏, 严正国
2005, 22(1): 67-71. doi: 10.11804/NuclPhysRev.22.01.067
摘要:
报道了快中子非弹性散射γ能谱测井, 非弹γ谱的新解析方法软件及应用. 新的解析方法包括:以标准非弹γ谱为基础, 对用NaI(Tl)探测器记录的256道地层非弹γ谱, 作定量解析, 求出各主要元素产额的方法; 以及求新的C/O和Ca/Si比的方法. 可同时求出三种C/O和Ca/Si比值, 即碳氧产额比、 重量百分含量比和原子比;钙硅比也如此. 所设计的软件功能强, 对于孔隙度为35%、 100%油饱和砂岩地层与100%水饱和砂岩地层(刻度井模型地层), 碳氧原子比之差值>0.33, C/O测井油水差值提高了60%以上, 并求得了地层的含油饱和度. 取得了国内首创和领先的成果. In this paper, the new analyzing method & software and applications of enelactic spectra from Carbon/oxygen spectrometry log is reported. It were included that enelastic Gammaray spectra(256 channels)of the formations by NaI(Tl) detector were analyzed quantitatively based on standard enelastic spectra, the methods which the ratio of elements yields and new ratio of C to O & of Ca to Si, the ratio of yield of C to O and the ratio of weight percent of C to O and the ratio of atoms C to O were found, and the corresponding ratio of Ca to Si were found simultaneously in new analyzing method. The differencevalue of the ratio of atoms C to O is greater than 0. 33 between 100% oil saturation and 100% water saturation in sandstone formation for porosity is thirtyfife percent. The differencevalue between oil and water increase by a factor of 60%. In addition oil saturations curves changed with the depth were computed.
C/O γ能谱测井新的解析理论和方法
庞巨丰
2005, 22(1): 72-75. doi: 10.11804/NuclPhysRev.22.01.072
摘要:
报道了快中子非弹性散射γ能谱测井(C/O γ能谱测井)新的解析理论和方法, 也就是由C/O能谱测井仪在井眼中获取地层的快中子非弹性散射γ射线、 NaI(Tl)探测器测量得到的256道谱, 再由实测非弹谱确定地层中主要元素C, O, Si, Ca和Fe等对非弹γ谱的贡献分额, 利用同一地层F因子相同, 求出C产额与O产额比, C的百分含量与O的百分含量和原子含量比, 及Ca和Si相应比值.A new analyzing theory and method of C/O spectrometry logging is reported. Fast neutron enelastic scattering γray spectra(256 channels) were acquired in borehole by NaI(Tl) detector. The enelastic scattering γray from major elements C, O, Si, Ca, Fe, etc. have the fractions of mixed enelastic spectrum in formation respectively. Because F factor is the same for identical formation, then the ratio of yield of C to O, the ratio of weight percent of C to O, and the ratio of atoms C to O could be found, and the corresponding ratio of Ca to Si was found.
可移动式中子监测隐性爆炸物系统的初步探索与研究
贾文宝
2005, 22(1): 76-78. doi: 10.11804/NuclPhysRev.22.01.076
摘要:
瞬发γ中子活化分析技术具有快速、原位、不需取样、准确、灵敏度高且能够实时多核素在线分析的特点,因此该技术是监测隐性爆炸物,尤其是非金属类爆炸物的最有效手段之一.在国内外有不少科技工作者对中子法监测隐性爆炸物技术进行了大量的研究,并取得了一定的成绩.主要对中子技术探测地雷和隐性爆炸物的各种方法和技术路线进行讨论,对同位素镅铍中子源和14 MeV脉冲中子管活化分析方法进行了初步探索研究,并对可移动式系统的源探的几何布置进行了探讨.Because it can on line analyze many elements quickly and precisely without sampling and movement, prompt gamma neutron activation analysis is one of the most effective methods to monitor latent dynamite especially nonmetal. Many researchers studied the neutron detecting latent dynamite technique and get some achievements. This paper mainly discussed each method and technology route of neutron detecting landmine and latent dynamite, studied the AmBe isotope neutron source and 14 MeV pulse neutron tube activation analysis, and analyzed the geometrical layout of movable system.
快中子照相胶片成像法的初步实验
裴宇阳, 唐国有, 郭之虞, 张国辉
2005, 22(1): 79-80. doi: 10.11804/NuclPhysRev.22.01.079
摘要:
利用9Be(d,n)反应在北京大学4.5MV静电加速器上产生小于7MeV能区的快中子,采用胶片法进行了快中子照相的初步实验.对快中子胶片成像法的基本性能进行了初步的测试和研究.用国产的原材料研制了一种适用于快中子照相的关键部件-快中子转换屏.实验结果表明研制的快中子转换屏能够满足快中子照相的需要.A preliminary experiment is conducted with directfilm method under the condition that fast neutron is generated by the reaction of 9Be (d,n) on the Peking University 4.5 MV Van de Graff, whose energy is lower than 7 MeV.Basic characteristics of direct-film neutron radiography system is researched with the help of samples in different materials, different thickness and holes of different diameter. The fast neutron converter, which is vital for fast neutron imaging, is produced with the materials made in china. The result indicates that fast neutron converter can meet the requirment of fast neutron imaging; what's more, further research of fast neutron imaging can be conducted on the accelerator and neutron-generator in China.
RFQ冷却聚束器
黄文学, 王玥, 徐瑚珊, 孙志宇, 肖国青, 詹文龙
2005, 22(1): 81-83. doi: 10.11804/NuclPhysRev.22.01.081
摘要:
简要介绍了RFQ冷却聚束器的基本原理, 并对设计中的RFQ冷却聚束器的特点和利用SIMION程序进行模拟的初步结果进行了讨论.The principle of RFQ (Radiofrequency Quadrupole) cooler and buncher is briefly introduced. The characteristics of the being designed RFQ cooler and buncher and the preliminary results simulated by using the SIMION code are discussed.
RIBLL终端LASCAR闪烁体阵列探测器研制进展
王金川, 肖国青, 郭忠言, 詹文龙, 徐治国, 祁辉荣, 陈志强, 武丽杰, 丁先利, 徐瑚珊, 孙志宇, 李加兴, 李琛, 高辉, 张力, 王猛, 胡正国, 陈立新
2005, 22(1): 84-87. doi: 10.11804/NuclPhysRev.22.01.084
摘要:
介绍了RIBLL终端LASCAR闪烁体阵列探测器的工作原理和结构特点. 描述了为满足放射性核束实验的要求而对阵列所作的重要改进. 给出了LASCAR构型优化改造的工作设想和实施步骤. The principles and structure characteristics of LASCAR scintillator array detector at RIBLL terminal are described. Special emphases are laid upon the latest progress for the development of LASCAR array detector to meet the requirements of the RIB experiments. The working plan and steps for optimizing configuration of the LASCAR multiunit neutron scintillator array detector are also presented.
复旦大学核微探针系统
吴延萍, 钟铃, 沈皓#, 宓詠
2005, 22(1): 88-90. doi: 10.11804/NuclPhysRev.22.01.088
摘要:
复旦大学现代物理研究所利用国家“211工程”的资助,从英国Oxford Microbeams公司引进了微探针关键部件,建立了新的核微探针实验装置.介绍了该装置各个组成部分,包括束线,靶室,聚集、扫描系统以及数据采集系统等.现已得到线度为μm量级的离子束.
A nuclear microprobe was set up at the Institute of Modern Physics of Fudan University.The key parts were imported from Oxford Microbeams Ltd.The hardware system of the microprobe,including beam line,target chamber,focusing system and DAQ system is introduced. About several micrometer could be achieved at present beam spot size.
赝火花脉冲电子束的特征
刘志坚, 江兴流, 乐小云, 文雄伟
2005, 22(1): 91-93. doi: 10.11804/NuclPhysRev.22.01.091
摘要:
基于电场递增效应理论,讨论了多极板赝火花脉冲电子束的特征.通过电子束对固体变色片和金属靶的轰击,对赝火花电子束的不稳定性、细丝效应和自箍缩效应等现象做了研究和分析.The characteristics of pulsed electron beam generated by multiplate pseudospark chamber (MPC) on the basis of field escalation effects have been described in this paper. The phenomena such as instability, filament effect, and self-pinch effect of pseudospark electron beam were studied and analyzedby the bombardment of solid evident films and metal targets.
γ射线和PET用晶体单元相互作用特性的研究
祁辉荣, 肖国青, 王金川, 郭忠言, 詹文龙, 徐瑚珊, 孙志宇, 李文飞, 李琛, 陈志强
2005, 22(1): 94-96. doi: 10.11804/NuclPhysRev.22.01.094
摘要:
γ射线与晶体单元的相互作用特性对于PET探测器的研制有着重要的参考意义. 通过实验测得了不同能量的γ射线在BGO, CsI, NaI 3种闪烁晶体中的探测效率、 能量分辨率等相互作用特性参数, 并与蒙特卡洛模拟结果进行了比较. 结果给出了最适合PET探测器的晶体单元. It’s important for development of PET detector that the interaction effect of γrays and scintillator units are studied. The detection efficiencies and energy resolutions of γrays for BGO, CsI and NaI crystal detector units are measured. Geant4 Monte Carlo simulations are compared with the experimental results. The results of the best detection units for PET detector are presented.
超重反冲余核时间探测器性能测试
徐华根, 徐瑚珊, 李文飞, 贾飞, 陈若富, 张雪荧, 马越, 李松林, 段利敏, 孙志宇, 肖国青, 郭忠言, 詹文龙
2005, 22(1): 97-99. doi: 10.11804/NuclPhysRev.22.01.097
摘要:
介绍了一种铝制内椭球面反射镜闪烁薄膜探测器,对其探测效率、光收集效率和时间性能的测试. 结果分析表明采用1 μm厚的BC498闪烁薄膜探测器测量实验中超重反冲余核, 探测效率接近100%, 时间分辨好于200 ps, 其性能满足超重反冲余核时间测量的要求. A thin plastic scintillator film detector with an inner ellipsoidal reflection mirror made of aluminum is introduced. Detection efficiency and light collection efficiency of the detector have been investigated. The time resolution of the detector has been also studied. The testing results show that the detection efficiency of BC498 with the thickness of 1 micron to be used in the coming superheavy synthesis experiments is approximately 100%, and the time resolution is better than 200 ps (σ). The performances of the thin plastic scintillator film detector meet the requirements for the time measurement of the superheavy element synthesis.
个人中子剂量气泡探测器研制
张贵英, 倪邦发, 李丽, 田伟之, 王平生, 黄东辉, 张兰芝, 刘存兄
2005, 22(1): 100-102. doi: 10.11804/NuclPhysRev.22.01.100
摘要:
中子固体气泡探测器被认为是唯一能够满足国际辐射防护委员会ICRP60要求的个人中子剂量计,它具有从低能中子到高能中子的平坦响应曲线和对γ射线不灵敏的优点.本工作将过热液滴均匀地分布在一种软聚合物中,制成了个人中子气泡剂量计,其灵敏度达到每毫雷姆40个气泡.还介绍了个人中子剂量气泡探测器的原理和制作过程.Neutron solid bubble detector was considered as a unique one for meeting the need of the personal neutron dosimeter recommended by International Committee of radiation protection,ICRP60.It has the flat response for neutron from low energy to high energy,and insensitive for gamma rays. In this work,superheated liquid drops were dispersed into a kind of soft polymer homogeneously.A personal neutron bubble dosimeter has been made,and the sensitivity reached to about 40bubbles/mrem.The principle and the processing procedure of bubble detector were also introduced in this paper.
瞬发γ活化分析系统的建立
张兰芝, 倪邦发, 田伟之, 王平生, 黄东辉, 刘存兄, 张贵英, 刘立坤
2005, 22(1): 103-105. doi: 10.11804/NuclPhysRev.22.01.103
摘要:
瞬发γ中子活化分析是重要的核分析方法之一,是H和B等轻元素的重要分析手段,近年来应用范围不断增加.概要介绍了瞬发γ中子活化分析的基本原理,重点介绍了中国原子能科学研究院重水研究堆热中子束瞬发γ中子活化分析实验装置以及50 keV-11 MeV的宽能区γ效率刻度方法.还应用瞬发γ中子活化分析分析了海底锰结核标准物质GSPN3中11种元素,结果与标准值基本一致.
Neutroninduced promptγ activation analysis(PGNAA),is one of the nuclear analytical method,which is a powerful tool for H,B,etc.undestructive determination.The applications of PGNAA are increased in recent years.In this paper,the basic principle of PGNAA was introduced briefly.The facilities of PGNAA in HWRR of China Institute of Atomic Energy as well as the efficiency calibration for a wide range gamma from 50 keV to 10 MeV were emphasized.A deep sea polymetallic nodule CRM,GSPN3 was analyzed by using PGNAA in this work,the results have agreement with the certified values.
模拟锆(Zr) 的基体效应对Ni3Al-x atoms % Zr晶界内聚性的影响(英文)
郑里平, 李斗星, 张秀荣
2005, 22(1): 106-109. doi: 10.11804/NuclPhysRev.22.01.106
摘要:
利用双粒子模型研究微量元素锆(Zr)的基体效应对Ni3Alx atoms % Zr晶界内聚性的影响. 模型显示, x\[锆(Zr)的基体浓度\]从0.1增加到0.5, 在晶界Zr富集是增加的; Ni富集和Al贫乏在x=0.3时趋于最大. 模型还显示, Ni3Alx atoms % Zr晶界的内聚性在x=0.3时为最佳.
不锈钢辐射损伤随温度和剂量的变化(英文)
郑永男, 普拉提.艾合买提, 徐勇军, 周冬梅, 王志强, 阮玉珍, 杜恩鹏, 袁大庆, 朱升云
2005, 22(1): 110-114. doi: 10.11804/NuclPhysRev.22.01.110
摘要:
用重离子辐照模拟和正电子湮没寿命技术研究了改进型316L不锈钢在21 和33 dpa辐照剂量下的辐照损伤在室温到802 °C温度范围随辐照温度变化和室温下0—100 dpa剂量范围随辐照剂量变化. 在580 °C左右实验观察到辐照肿胀峰, 在21 和33 dpa辐照剂量下相应的空位团分别由14和19个空位组成, 尺度分别为0.68 和0.82 nm. 空位团尺寸随辐照剂量增加, 在100 dpa时空位团由8个空位组成, 尺度为0.55 nm. 实验结果表明, 在改进型316L不锈钢中辐照损伤随辐照温度变化更灵敏.
PdAgHx金属氢化物正电子湮没研究
左翼, 郑永男, 周冬梅, 杜恩鹏, 袁大庆, 段晓, 朱升云
2005, 22(1): 115-117. doi: 10.11804/NuclPhysRev.22.01.115
摘要:
在77—295 K温区和氢浓度0—0.35范围采用正电子湮没寿命测量方法研究了Pd0.75Ag0.25Hx氢化物合金. 充氢后正电子湮没寿命谱可以用两个寿命成分表征. 短寿命成分τ1不随温度和氢浓度变化, 是自由正电子湮没寿命; 长寿命成分τ2及其相对强度I2不随温度变化, 但随氢浓度的增加分别增大和减小, τ2是氢气泡捕获的正电子湮没寿命, τ2增大和I2减小说明随氢浓度增大氢聚集成的气泡的尺度增大, 而浓度减小. 实验结果表明, 氢脆的微观机理是氢气泡致脆. The metal hydride PdAgHx with a hydrogen concentration x ranging from 0 to 0.35 has been investigated by positron annihilation lifetime method in the temperature region between 77 K and 295 K. The measured lifetime spectra in metal hydride PdAgHx are characterized by two lifetimes τ1 and τ2. The short lifetime τ1 is independent of both hydrogen concentration and temperature, which is ascribed to the annihilation lifetime of free positrons. The long lifetime τ2 and its intensity I2 do not change with temperature, while τ2 increases and I2 decreases with increasing of hydrogen concentration. τ2 is attributed to the lifetime of positrons trapped at the hydrogen bubble. The increase of τ2 indicates the growth of the hydrogen bubble, and the decrease of I2 shows the reduction of the hydrogen bubble concentration. The experimental result shows a microscopic mechanism that the hydrogen bubble produced causes hydrogen embrittlement.
纳秒强流脉冲电子束强化金属表面的研究
刘志坚, 乐小云, 江兴流
2005, 22(1): 118-121. doi: 10.11804/NuclPhysRev.22.01.118
摘要:
利用多极板赝火花放电装置产生的高功率脉冲电子束对不同类型的钢, 如45#, 65Mn, T8, 9Cr18和GCr15等进行轰击, 研究其在金属材料表面改性中的应用. 样品表面的显微硬度和耐腐蚀性测试结果以及扫描电子显微镜(SEM)的观察分析表明, 经电子束轰击后, 这些材料在结构、组织和性能上发生了明显的变化, 轰击中心区域的显微硬度和耐蚀性明显提高. 基于一维热传导方程对材料表面的冷却速率进行了估算, 对电子束与金属材料的作用过程进行了理论分析. 结果表明, 高功率密度脉冲电子束与金属材料相互作用, 表面冷却速率高达1. 2×1012 ℃/s, 使材料表面局部瞬间达到熔化, 产生骤热急冷过程.
High power density electron beams generated by multiplate pseudospark discharge chamber, have been used to bombard various kinds of steel targets such as 45#, 65Mn, T8, 9Cr18, GCr15, etc, and studyits applications for modification of metal surface. The microhardness and corrosive resistance property have been measured and the morphology was obtained by using SEM analysis. The results showed that the surface properties and structure of the matevials bom barded have been modified; in the bombarded center area, the microhardness as well as corrosive resistance property was improved obviously. The interactions befween the electron beam and metal materials were theoretically considered and discussed on the basis of simple calculation with one dimensional thermal transfer equation. It showed that the cooling rate of metal surface with 1.2×1012 ℃/s was so high that caused the metal surface instant melted, and abrupt cooled.
射线检测管道垢厚方法的研究进展
丁小平, 刘圣康
2005, 22(1): 122-124. doi: 10.11804/NuclPhysRev.22.01.122
摘要:
报告了我国开展射线检测原油管道垢厚的研究进展. 介绍了γ射线透射检测垢厚的基本原理、 模拟实验装置及主要研究成果. 研究表明, 研制透射型测垢仪是可行的. 另外, 还给出了南京大学关于表面型中子测垢仪和γ射线测垢仪的初步预研结果.
散射光子对60Co集装箱CT检测系统的影响
尹在哲
2005, 22(1): 125-126. doi: 10.11804/NuclPhysRev.22.01.125
摘要:
用蒙特卡罗(EGSnrc)方法模拟计算集装箱(大型客体)CT检测系统60Co光子能谱,讨论和分析了该检测系统的客体散射光子对影像分辨率的影响,为进一步提高集装箱(大型客体)CT检测系统数字成像分辨率提供了理论依据.
密封容器中钚材料同位素丰度和年龄的测量
刘素萍, 龚建, 郝樊华, 伍怀龙, 胡广春, 向永春, 迮仁德, 章建华
2005, 22(1): 127-130. doi: 10.11804/NuclPhysRev.22.01.127
摘要:
根据相对效率法的原理,利用PC/FRAM分析软件,开展了用高分辨γ谱仪测量密封容器中钚材料的同位素丰度和年龄的实验研究.研究结果表明,同位素丰度和年龄的分析精度随能谱测量精度的提高而提高,如果能谱的测量精度不够,通过PC/FRAM分析得出的钚材料的同位素丰度和年龄有偏低的可能.因此,在能谱测量过程中,建议通过监测某个特征峰的峰面积计数来判定239Pu丰度和年龄的测量精度是否已满足测量要求.Based on the concept of relative detection efficiency, some experiments have been conducted to measure the isotopic abundance and the age of the plutonium material in a sealed container by a high-resolution γ-ray spectrometer. The PC/FRAM software analyzes the spectra. The study shows that the analysis precision of the isotopic abundance and the age will rise as the spectral measurement precision increases, and that If the spectral measurement precision is not enough, the analyzed results by the PC/FRAM software might be lower. Hence, the study suggests that a spectral peak is monitored to show lights on the spectral measurement precision during the process of spectrum acquirement.
核分析技术在古陶瓷中的应用研究
冯松林, 徐清, 冯向前, 雷勇, 程琳, 汪燕青
2005, 22(1): 131-134. doi: 10.11804/NuclPhysRev.22.01.131
摘要:
古陶瓷是用瓷土加工后烧制的,它携带着的产地信息和反映古代不同时期加工工艺的年代特征,是分析和研究古陶瓷的科学依据.根据现代核分析技术的功能,阐述它在古陶瓷研究中将发挥的作用和应用前景.Ancient ceramic is fired with porcelain clay.It contains various provenance information and age characteristic.That is the scientific foundation to analyze and research the ancient ceramic with modern analysis methods.According to the property of nuclear analysis technique,the function and application of it is discussed.
陕西西岳庙古琉璃胎料来源的INAA研究及多元统计分析
程琳, 冯松林, 吕智荣
2005, 22(1): 135-137. doi: 10.11804/NuclPhysRev.22.01.135
摘要:
用仪器中子活化分析研究了陕西立地坡明代地层和陕西西岳庙宋、元、明、清早期、清晚期4个地层出土的古琉璃胎中的主量和微量元素, 并对实验数据进行多元统计分析. 结果表明, 陕西西岳庙从宋到清早期古琉璃胎料很稳定, 其原料可能来自本地; 清晚期古琉璃胎料与宋到清早期的古琉璃之间存在明显的区别, 明代3个样品和清晚期的古琉璃制造原料与立地坡出土的古琉璃其成分相近, 西岳庙清晚期的古琉璃可能来自陕西立地坡窑烧制.
不同窑口古代青瓷的产地特征的中子活化分析
冯松林, 范东宇, 冯向前, 徐清, 程琳, 雷勇, 权奎山, 沈岳明, 张文江, 禚振西
2005, 22(1): 138-141. doi: 10.11804/NuclPhysRev.22.01.138
摘要:
产地属性是科学鉴别遗址和墓葬中出土的古陶瓷烧制产地的重要依据.用仪器中子活化(INAA)有损分析了浙江寺龙口越窑、江西洪州窑和陕西耀州窑出土的古瓷碎片样品,通过实验数据的统计分析,结果表明3个窑口古瓷的元素组成具有各自的特征,它们之间具有可以区分的依据,寺龙口越窑与南方江西洪州窑的制胎原料关系较近,与北方陕西耀州窑的关系较远.这些试验结果将为古陶瓷地研究提供重要参数.
Provenance characteristic is an important scientific parameter to identify ancient porcelain wares unearthed from sites and graves.The porcelain samples of SiLongKou kiln of Zhejiang Province,HongZhou kiln of Jiangxi Province and Yao Zhou kiln of Shanxi Province have been analyzed with neutron activation analysis(NAA) in this paper.The experimental data were studied with statistic methods.The results show that the chemical compositions of porcelain body samples for three kilns were different. The difference was been able identified. The body materials of both SiLongKou Yue kiln and HongZhou kiln of Jiangxi were similar. The samples of YaoZhou kiln in north of China existed obvious difference.

历代洪州窑古瓷的元素组成特征的中子活化分析研究
冯向前, 冯松林, 张文江, 樊昌生, 权奎山
2005, 22(1): 142-144. doi: 10.11804/NuclPhysRev.22.01.142
摘要:
对江西洪州窑从东汉晚期至晚唐五代8期400个瓷胎样品进行了中子活化分析, 分析结果显示碱金属元素Na和Rb、 碱土金属元素Ba及Fe等作为胎的助熔剂元素随年代的变化趋势相似, 都呈现出两头高中间低的U字形变化规律, 其中Fe作为呈色元素, 其含量的高低与瓷胎颜色的深浅是一致的. 分析结果还揭示洪州窑的发展与衰落以及窑址的不断变迁可能都与制瓷原料的发现与消耗有关. 对分析数据进行主成分分析, 可以将不同时期烧制的瓷胎样品大致分为5组: (1)东汉晚期东吴时期; (2)两晋和南朝时期; (3)隋代; (4)初唐和盛唐时期; (5)晚唐五代时期. 400 sherds were collected from Hongzhou Kiln covering 8 periods from Eastern Han to Late Tang Dynasty/the Five Dynastied and their bodies were analysed by NAA. The results show that the elemental contents in different samples are quite distinct, even for those in the same period. It means no single element can be used as “fingerprint” to distinguish the period. The curves of the contents of Na, Rb, Ba and Fe varying with time are very similar, like “U” shape. As a colorant element, the content of Fe is consistent with the color of the body. The higher content of Fe, the more dark of the body. The outcome of principal component analysis (PCA) indicate that most of the sherds can be classified into 5 groups: (1) Eastern Han & Eastern Wu; (2) Western Jin, Eastern Jin and Southern Dynasties; (3) Sui; (4) Early Tang and Middle Tang; (5) Late Tang & Five Dynasties.
抗金属污染的超绝缘材料研究
刘存兄, 倪邦发, 田伟之, 张兰芝, 张桂英, 黄东辉, 王平生, 刘立坤
2005, 22(1): 145-147. doi: 10.11804/NuclPhysRev.22.01.145
摘要:
使用串列加速器产生的32S离子对不同厚度的聚碳酸酯、聚脂膜进行了不同密度的辐照,并在不同温度、不同碱度和不同蚀刻时间条件下,研究了蚀刻对孔形状、孔径以及膜表面损耗等的影响.通过表面金属镀膜的方式研究了该膜的抗金属污染的绝缘性能.结果显示,其抗金属污染的绝缘性能得到了大幅度提高.
直流磁控溅射沉积含He钛膜的研究
施立群, 金钦华, 刘超卓, 徐世林, 周筑颖
2005, 22(1): 148-152. doi: 10.11804/NuclPhysRev.22.01.148
摘要:
研究了用He/Ar混合溅射气体的直流磁控溅射制备钛膜中,He的掺入现象.分析结果表明,大量的He原子(He/Ti原子比高达56%)被均匀地引入到Ti膜中,其He含量可由混合溅射气体的He分量精确控制.通过调节溅射参数,可实现样品中He的低损伤引入.研究还发现,溅射沉积的含氦Ti膜具有较高的He成泡剂量和高的固He能力,这可能是溅射沉积形成了纳米晶Ti膜所致.纳米晶Ti膜较粗晶材料具有很高浓度的He捕陷中心,使He泡密度增大而泡尺寸减小.随He引入量的增加,Ti膜的晶粒尺寸减小,He引起的晶体点阵参数和X射线衍射峰宽度增大,晶体的无序程度增加.Helium trapping in the Ti films deposited by DC magnetron sputtering with a He/Ar mixture was studied. He atoms with a surprisingly high concentration (He/Ti atomic ratio is as high as 56%)incorporate evenly in deposited film. The trapped amount of He can be controlled by the helium partial amount. The introduction of the helium with no extra damage(or very low damage) can be realized by choosing suitable deposition conditions. It was also found that because of the formation of nanophase Ti film a relative high He flux for bubble formation is needed and the amount of the retain He in sputtering Ti films is much higher than that in the coarsegrain Ti films. The nanophase Ti film can accommodate larger concentration of trapped sites to He, which results in a high density and small size of the He bubbles. With the increasing He irradiation flux, the grain size of Ti film decreases and the lattice spacing and width of the X ray diffraction peak increase due to the He introduction, and the film tends to amorphous phase.