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2010年  第27卷  第3期

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核物理
Gammasphere 上裂变丰中子核核结构若干前沿领域的新进展(Ⅰ: 第一和第二部分)(英文)
罗亦孝, J.H.Hamilton, J.O.Rasmussen, A.V.Ramayya, C.Goodin, A.V.Daniel, N.J.Stone, 朱胜江, J.K.Hwang, 刘少华, C.J.Beyer, 李科, H.L.Crowell, D.Almehed, S.Frauendorf, A.Covello0, V.Dimitrov, 张敬业, 车兴来, 姜卓, D.Fong, A.Gelberg, I.Stefanescu, A.Gargano0, E.F.Jones, P.M.Gore, I.Y.Lee, G.M.Ter-Akopian, Yu.Ts.Oganessian, M.A.Stoyer, R.Donangelo, 马文超, J.D.Cole, J.Kormicki, 张学谦, S.C.Wu, J.Gilat, T.N.Ginter, S.J.Asztalos0
2010, 27(3): 229-251. doi: 10.11804/NuclPhysRev.27.03.229
摘要:
使用Gammasphere多探测器系统对252Cf裂变源瞬发γ射线进行γ-γ-γ和γ-γ(θ)符合测量, 裂变丰中子原子核核结构若干前沿领域的深入研究获得了新的进展。高达5.7×1011以上的三重和更高重符合事件的数据统计, 以及更少压缩的三维数据为宽广未知丰中子核区的寻找和研究提供了有利的条件。在具有重要物理意义的若干丰中子核区首次建立, 或显著扩展了一批包括转晕态和转晕附近能态的高自旋能级纲图。
在偶-偶丰中子核110, 112Ru和108Mo中鉴别出了手征对称破缺结构。丰中子 110, 112Ru附近核的三轴形变基态具有最低的能量, 在它们之中已确认了接近最大值的三轴形变。在这些Ru和Mo同位素中观察到的手征双线能带展示出手征破缺的一切特征, 特别是其理想的能量简并, 表明它们在迄今已报道的手征破缺结构中, 具有最好的手征特性。研究了手征结构从具有γ软度的108Ru到具有大三轴形变的110, 112Ru的过渡。斜轴推转(TAC)和随机相近似(RPA)理论计算成功地拟合了在这些偶偶丰中子核中观察到的手征双线能带的特性, 并指定其为软手征振动态。在这些偶偶核中观察到的手征破缺不可能归纳为奇奇核中那样的简化的几何图像。前者来自闭壳外所有中子的相互作用。
对双幻核132Sn附近N=83同中素链的系统研究为这个极富吸引力的核区提供了大量新的谱学信息。N=83 同中素135Te(Z=52), 136I(Z=53), 137Xe(Z=54),138Cs(Z=55) 和139Ba(Z=56)的最新能级信息, 特别是首次建立的138Cs高自旋能级纲图和壳模型理论计算表明,Z=50质子闭壳外少数g7/2价质子激发同N=82中子闭壳外之唯一f7/2价中子的耦合对该核区能级结构具有关键作用。观察到了132Sn和208Pb附近核区谱学信息的相似性和相对应的三粒子和五粒子态。在135Te中观察到了磁转动, 这是在双幻核132Sn附近观察到的首例磁转动。
New insights have been gained into the frontiers of nuclear structure of neutronrich nuclei by means of γ-γ-γ and γ-γ(θ) coincidences of prompt γ rays emitted in the spontaneous fission of 252Cf at Gammasphere. Over 5.7×1011 tripleand higher fold coincidence events and the lesscompressed cube data provide excellent conditions for searches and studies over a wide unknown range with more neutron excess. Highspin yrast and near yrast level schemes of neutronrich nuclei in regions of physics interest have been identified for the first time, or extensively extended and expanded compared to previous preliminary measurements ......
145Er的β延发质子衰变性质研究
马 飞, 周小红, #, 郑勇, 徐树威, 谢元祥, 陈亮, 张玉虎, 李占奎, 强赟华, 雷祥国, 郭应祥, 郭松, 丁兵, 王海霞, 李广顺, 周厚兵
2010, 27(3): 252-256. doi: 10.11804/NuclPhysRev.27.03.252
摘要:
通过92Mo(58Ni, 2p3n)熔合蒸发反应生成了非常缺中子核145Er。利用氦喷嘴带传输系统把研究目标核传输到低本底测量站, 进行了质子γ符合测量, 得到了不受同量异位素干扰的145Er的β延发质子谱。经过仔细分析与延发质子符合的γ谱, 发现了145Er的11/2-同核异能态具有β延发质子衰变性质。经拟合退激144Dy不同激发态γ跃迁的衰变曲线, 得出145Er的1/2+基态和11/2-同核异能态的半衰期分别为(1.6±0.6)和(0.6±0.1) s。最后, 简单介绍了中重质量区缺中子新核素的合成及衰变研究计划。The neutrondeficient isotope 145Er was produced via the fusionevaporation reaction 92Mo(58Ni, 2p3n). The reaction products were transported to a low background counting area using a Hejet tape transport system, and protonγ coincidence measurements were carried out. Based on the analysis of γ transitions in coincidence with βdelayed protons, the βdelayed proton decay of an νh11/2 isomer in 145Er was proposed. By fitting the decay curves of the γ transitions depopulating the lowlying states in 144Dy, the halflives of the groundstate and the νh11/2 isomeric state in 145Er were deduced to be (1.6±0.6) and (0.6±0.1) s, respectively. An experimental plan to synthesize new βdelayed proton precursors in the mediumheavy mass region has been presented.
156Gd基态SU(3)→O(6)相变的一种微观理解
雷玉玺, 张欢, 石筑一, #, 汪红, 童红
2010, 27(3): 257-262. doi: 10.11804/NuclPhysRev.27.03.257
摘要:
γ射线能量自旋曲线指认156Gd核基态具有SU(3)和O(6)两种对称性。 基于微观sdIBM-max方案和单粒子能量实验值, 用两组核子之间的对作用、 四极对作用、 四极四极作用的等效强度参数, 都很好地再现了这两种能谱及其演化过程。 计算结果揭示出对基态相变的一种新理解: SU(3)的基准态是低激发低有序态, 而O(6)基准态则是高激发高有序的, 它们有临界区6+1—8+1态; 当核退耦到临界区时, 高有序基准态释放多余的有序结构能, 导致低有序基准态重组, 实现减速旋转驱动高有序核向着低有序核过渡的量子相变。最后用156Gd核的势能曲面作了直观说明。
The γray energy over spin curves identifies that there are the SU(3) and O(6) symmetries in the groundstates of the 156Gd nucleus; by means of the microscopic sdIBMmax approach and signalparticle experimental energies the spectra of those two symmetries and their transient process are successfully reproduced through two parameters of nucleonnucleon effective interaction with pairing plus quadrupole pairing plus quadrupolequadrupole forces. The calculated results reveal a new way to recognize groundstates quantum phase transition, in which the basicstate of the SU(3) symmetry is a lowlying and lowordered state, while one of the O(6) are a highlying and highordered state, their critical region is between 6+1—8+1 states, the highordered basicstate releases spare orderedstructure energy, reducing rotationspeed, thus causing the restructure of lowordered basicstate and accomplishing the quantum phase transition from the highordered phase into the lowordered phase, the shape phase transition takes place along the yrast line of nucleus when it deexcited to the critical region. Because the structural phase transition takes place by noobvious charge of boson structure constants in the critical region it is a benignancy and calm transition with respect to its macroscopic behave. The potential energy surface of 156Gd nucleus has been illustrated to visualize.
α发射数可作为提取同位旋相关平均场的灵敏探针
郭文军, 郭双鹤, 孙长安
2010, 27(3): 263-266. doi: 10.11804/NuclPhysRev.27.03.263
摘要:
利用同位旋相关的量子分子动力学, 对中能重离子碰撞过程中的α发射数的同位旋效应进行了分析。 研究表明, α发射数强烈地依赖于同位旋相关平均场的影响, 而与同位旋相关核子核子碰撞截面的依赖较弱, 可以作为提取同位旋相关平均场信息的灵敏探针。 由于实验上α粒子发射数的观测比较容易, 而且在很宽地能量范围内, 无论丰中子系统还是缺中子系统都较好地满足上述规律, 这样就可以通过实验上对α发射数的探测, 来提取介质中同位旋相关平均场的信息。 同时建议由实验对缺中子系统的质子发射数进行探测, 从中提取同位旋相关核子核子碰撞截面的信息。 The α emissions in heavyion collisions at intermediate energies are studied by using isospindependent quantum molecular dynamics model. The number of α emitted is found to be strongly dependent on the isospindependent meanfield and weakly on the nucleonnucleon cross sections. The number of α emitted is easy to be measured in experiment and the above conclusion is still available no matter in neutronrich systems or in neutrondeficient systems in a wide energy region, so it can be used as an excellent probe for extracting information of the isospindependent meanfield. After several years searching, some information of the isospin asymmetry equation of state has been obtained in theoretically. We suggest to investigate the number of α emitted in neutronrich systems and the number of proton emitted in neutrondeficient systems experimentally to obtain more information of the isospindependent meanfield and the isospindependent nucleonnucleon cross section.
核外环境对衰变率的影响
周书华
2010, 27(3): 267-273. doi: 10.11804/NuclPhysRev.27.03.267
摘要:
核衰变速率是否受核外环境影响, 一直是核物理研究的热点问题。 这一问题不仅对核物理基础研究很重要, 而且与天体物理、 地质年代学、 凝聚态物理和核废物处理等都有重要关系。 旨在对这方面研究工作的进展做一介绍。
The possible change of nuclear decay rates in different environments has long been an interesting topic due to its importance not only in nuclear physics but also in astrophysics, geological dating, condensed matter physics, disposal of nuclear waste etc. The progresses in the investigation of variations in nuclear decay rates are reviewed.
高能Pb-Pb中心碰撞中产生的Λ和强子的横质量分布和快度分布(英文)
谢文杰
2010, 27(3): 274-279. doi: 10.11804/NuclPhysRev.27.03.274
摘要:
用多源理想气体模型和三火球模型分析并计算了能量在40, 80, 158 AGeV下中心PbPb碰撞中所产生的Λ和强子的横质量分布和快度分布, 发现模型计算的结果与NA49合作组的实验结果相一致。The transverse mass and rapidity distributions of Lambda and Antilambda hyperons produced in central PbPb collisions at 40, 80, and 158 AGeV are described by the multisource ideal gas model and the threefireball model. The results calculated by the models are compared and found to be in agreement with the experimental data of the NA49 Collaboration.
加速器
HIRFL微束辐照装置偏转磁铁的安装准直
王少明, 陈文军, 杨胜利, 蔡国柱, 郭艺珍, 周光明, 满开第, 宋明涛
2010, 27(3): 280-283. doi: 10.11804/NuclPhysRev.27.03.280
摘要:
微束辐照装置是将辐照样品的束斑缩小到μm量级, 能够对辐照粒子进行准确定位和精确计数的实验平台, 是开展辐照材料学、 辐照生物学、 辐照生物医学和微加工的有力工具。 μm量级的束流对设备的准直安装也提出了极高的要求, 对于HIRFL系统微束线上的二极磁铁, 由于其所在位置的空间相当狭小, 使得设计就位时磁铁的位置及角度与地面做基准时的不同, 这给安装准直工作带来了挑战。 通过引入变化的基准坐标值的办法, 有效解决了这一难题, 使全部磁铁安装误差都控制在了要求的公差范围之内。 Microbeam irradiation facility is a experiment platform, which can reduce the beamspot on the irradiated sample to micrometer level, and can accurately locate and count the radioactive particles. It is a powerful research tool for the irradiation material science, irradiation biology, irradiation biomedicine and micro mechanical machining. The microbeam irradiation facility requires the precise work for installation and alignment. These conditions make magnet’s change for directions and positions because the location space of dipole magnets in microbeam line of HIRFL(Heavy Ion Research Facility in Lanzhou) is very small. It is a challenge for the installatior and alignment work of magnets. It was solved by transforming coordinates of benchmarks of magnets, which controlled the error of magnet setup within error tolerance range.
核技术
核辐照技术在中药领域中的应用
梁剑平, 李雪虎, 陆锡宏, 陶蕾, 王曙阳
2010, 27(3): 284-290. doi: 10.11804/NuclPhysRev.27.03.284
摘要:
核辐照应用于中药领域的研究得到人们广泛关注。综述了核辐照在中草药的栽培、育种和消毒等方面的应用, 指出辐照诱变技术与生物技术相结合将为提高细胞突变率和加快中草药遗传改良开辟广阔前景。The application of nuclear irradiation in the field of traditional Chinese medicine has received much attention. In this paper we reviewed the application of nuclear radiation on the cultivation, breeding and disinfection of traditional Chinese medicine, and pointed out that the combination of radiationinduced mutagenesis and biological technology would promise broad prospects for increasing the cellular mutation rate and speeding up the genetic improvement of traditional Chinese medicine.
Micromegas中子探测器位置分辨特性的Monte-Carlo研究(英文)
韦峥, 李昊翔, 张毅, 汪珊珊, 胡碧涛, #
2010, 27(3): 291-295. doi: 10.11804/NuclPhysRev.27.03.291
摘要:
利用GEANT4和Garfield气体探测器模拟程序模拟了Micromegas中子探测器位置特性。 在漂移极上加一层聚乙烯薄膜作为转换材料, 通过反冲质子法测量中子的位置。 提出了一套通过设定探测器上层结构的方案来得到探测器的位置分辨特性。 通过对模拟结果的分析与比较, 得到一种易于测定探测器位置分辨特性的方法。 该工作不仅可以优化气体探测器结构设计, 缩短实验周期, 而且还能极大程度地节约经费。 In the present work, the spatial resolution of Micromegas as a neutron detector was simulated with GEANT4 and Garfield program. The polyethylene foil was used as neutron converter. A new method based on structural setting on the toplayer of the detector was adopted to obtain spatial resolution. According to our simulation, it turned out to be a better spatial resolution, and this method was easily realized in experiment.
用于辐射复合与双电子复合实验的低能离子闪烁探测器
孟令杰, 马新文, #, 刘惠萍, 岳珂, 张鹏举
2010, 27(3): 296-299. doi: 10.11804/NuclPhysRev.27.03.296
摘要:
为了在CSRm的电子冷却器上进行辐射复合以及双电子复合实验, 需要探测能量小于4 MeV/u的离子, 因此设计了新的置于超高真空环境的CsI(Tl)闪烁探测器, 探测器采用的光电倍增管为R7525(Hamamatsu)。 介绍了新闪烁探测器的结构, 并对其进行了性能测试。 测试结果表明, 该探测器对高、 低能离子均有良好的响应, 探测器的信号十分明显。 探测器的最高计数率可以达到106 ions/s, 并且探测器附近的真空度可达10-10 Pa量级, 能够满足辐射复合与双电子复合实验以及储存环对真空的要求, 为今后在CSRm上进行复合实验打下了良好的基础。 A new CsI(Tl) scintillation detector readout with R7525 PMT(Hamamatsu)is designed to detect low energy (<4 MeV/u) ions in radiative recombination and dielectronic recombination experiments at the main cooler storage ring in Lanzhou. The structure of the scintillator detector is described in this paper. The detector is tested with α source and ion beams, respectively. The signals from background, 200 MeV/u C6+ and alpha radioactive source are recorded and analyzed. The results show that the detector has good response to highand lowenergy ions. The maximum counting rate of the detector can reach 106 ions/s and the vacuum level near the detector can reach 10-10 Pa, both are good for recombination experiments. The installation of the new detector to CSRm is of great help for future radiative recombination and dielectronic recombination experiments.
新型国产LaCl3∶Ce晶体γ/n甄别能力研究
李忠宝, 胡孟春, 郭洪生, 周刚, 杨高照, 曾清
2010, 27(3): 300-303. doi: 10.11804/NuclPhysRev.27.03.300
摘要:
对国内最新研制的高光产额(~50000 photons/MeV)、 快响应(~25 ns)无机晶体LaCl3∶Ce的γ/n甄别能力进行了研究。利用MC模拟程序进行建模计算, 得出LaCl3∶Ce晶体的γ/n为19.56; 利用DPF中子源DD靶进行实验测量, 结果表明该晶体的γ/n高于19。理论计算结果与实验结果相符合。该晶体可以应用于中子、 γ混合辐射场中γ脉冲的测量。
In this paper, the γ/n discriminability of LaCl3∶Ce scintillator is studied. This scintillator has high output(50000 photons/MeV) and fast principal decay time constant(~25 ns). γ/n discriminability of LaCl3∶Ce is 19.56 with MCNP calculation and larger than 19 in the experimental measurement with Dense Plasma Focus facility. The calculation is in agreement with the experiment result. This crystal may be applied to measuring the gamma pulse in the neutron and gamma mixed radiation field.
用于测量ICF靶丸内氚活度的电离室的设计
刘学, 叶成钢, 贾鹏, 李佳#
2010, 27(3): 304-308. doi: 10.11804/NuclPhysRev.27.03.304
摘要:
设计了一种可测量ICF靶内氚含量的圆柱电离室。密封部件的设计抛弃了传统的橡胶密封而采用全金属密封, 以消除橡胶、 塑料对氚的强吸附性产生的电离室污染。为防止氚扩散污染电离室的内壁, 内壁镀上一层2 μm的Au膜。在中心电极和外电极间引入保护电极以降低低水平放射性测量时的电极漏电流。保护电极和中心电极间的绝缘材料, 以及保护电极和外电极间的绝缘材料分别选择绝缘性好、 耐高温的蓝宝石和Al2O3陶瓷。另外, 基于对ICF靶参数测量的特殊要求, 在电离室中设计了一个压碎靶丸释放氚的装置。最后, 通过物理建模和复合损失计算, 得到了优化的电离室参数。A cylindrical ionization chamber was designed for the measurement of the tritium at the level enclosed in inertial confinement fusion(ICF) targets. In stead of the conventional rubber seals, the metallic seals was adopted to reduce the chamber contamination caused by the strong tritium absorption of rubber and plastics. A 2 μmthick Au layer was plated on the inner wall of the chamber to avoid the contamination due to tritium diffusion in the chamber. The protective electrode was introduced to reduce the leakage current when measuring the lowlevel radioactivity. Sapphire was employed as an insulator between the protective electrode and central electrode, while Al2O3 ceramic was used in between the protective electrode and the external electrode. In addition, to meet the specific requirements on the measurement of ICF targets’ parameters, a component used to crash the target to release tritium was designed in the chamber. Finally, the optimal chamber parameters were obtained in terms of physics modeling and combination loss computation.
交叉学科
重离子治癌相关研究
叶 飞, 李强, #
2010, 27(3): 309-316. doi: 10.11804/NuclPhysRev.27.03.309
摘要:
癌症是现代医学的难题, 一直危害着人类的健康。放射治疗是癌症治疗的有效手段之一。由于重离子束在物理学和生物学性质上所具有的优势, 它已成为放疗用的最佳射线。简述了重离子治癌的发展历程、 现状以及特点, 详细讨论了在医学物理和放射生物学研究领域值得关注的若干热点问题。
Being a challenge to modern medicine, cancer endangers people’s health. Radiotherapy is one of the most successful means to treat cancer. Owing to their advantages in physics and biology, heavy ions have become the optimal particles used in radiotherapy. The features of heavy ion therapy are described, and several hot topics in medical physics and radiobiology are discussed in detail.
放疗中二次原发性肿瘤的研究进展
张昕, 张红, #
2010, 27(3): 317-322. doi: 10.11804/NuclPhysRev.27.03.317
摘要:
回顾了辐射致癌方面的研究进展和二次原发性肿瘤在放射医学领域中的提出和发展, 总结了辐射致癌的一般特征以及主要医用放射性装置对二次原发性肿瘤发病的影响。重点阐述了年龄、 性别、 组织敏感性和照射剂量等重要影响因素在二次原发性肿瘤发病上造成的差异和原因。讨论了部分潜在的影响因素。展望了二次原发性肿瘤方面研究的前景和在放射治疗领域中的重要意义。
The progress in radiocarcinogenesis research and recent concerns about second primary cancer incidence after radiotherapy are reviewed. Several generalizations about radiation carcinogenesis and a brief look into medicaluse radiation sources are also summarized. The mostly confirmed dominant risk factors of second primary cancer are elucidated, some potential risk factors are proposed and discussed briefly. At the end of this review we presented our perspective on the future of second primary cancer research and its potential benefit.
小肠电离辐射损伤研究进展
马晓飞, 张红, #
2010, 27(3): 323-237. doi: 10.11804/NuclPhysRev.27.03.323
摘要:
肠道的电离辐射损伤是腹部及盆腔肿瘤放射治疗过程中的剂量限制因素。综述了小肠电离辐射损伤的临床症状、 小肠上皮及粘膜下层基质改变、 信号分子表达变化、 组织学变化和超微结构变化。简介了中国科学院近代物理研究所重离子束辐射生物医学重点实验室正在进行的有关小肠重离子辐射损伤及防护方面的研究工作。
Intestinal ionising radiation injuries are a dose limiting factor in the course of radiotherapy of abdominal and pelvic malignancies. In this paper it is reviewed that ionizing radiation injuries of small intestine, including clinical symptoms, epithelium and submucosa changes, signal molecular expression changes, histological and ultrastructure changes. The ongoing works of our laboratory on subjects of intestinal injuries induced by heavy ions and protection against these injuries are also presented.
12C6+高能重离子辐照大葱损伤及其分子生物学效应
李姝汶, 王晓军, 段翼远, 钱平平, 李文建, 侯岁稳, #
2010, 27(3): 328-334. doi: 10.11804/NuclPhysRev.27.03.328
摘要:
利用30, 90, 180 Gy 3种剂量的12C6+重离子束辐照大葱种子, 研究其在细胞水平和农艺性状的诱变效应并进行RAPD分析。通过与M1代的研究结果比较后表明: 经过不同剂量12C6+重离子照射后能有效地诱导大葱细胞形成微核和染色体畸变, 这种诱变效应, 在M2代仍然有所表现。M1代大葱结果期的株高、 白长、 花序直径和种子产量随辐照剂量增加产生明显差别, 其中30 Gy辐照组增幅最大。大葱总水溶性蛋白质和维生素C的含量在30 Gy组中积累最多, 在90 Gy组有明显下降。与M1代一致, M2代中大葱染色体微核率及RAPD分析所得的DNA多态性比率仍然与辐照剂量呈正相关, 但比率整体下降; 说明高能量重离子辐照造成的DNA变异在M2代被修复和淘汰。
Abstract: The Allium fistulosum L. seeds were irradiated by 12C6+ heavy ions to the dosages of 30, 90, 180 Gy, the mutagenic effect in the aspect of the cell level and the agronomy was studied and the RAPD analysis was carried out. Comparision with the conclusion of M1 gengeration indicates that the Cytological damage, micronucleus and chromosomal aberration caused by radiation formed in the cells of Allium fistulosum L., and this kind of effect still existed in the M2 generation. There is a negative correlation between some of the growth indexes such as plant height, diameter of onion white and irradiation dosage to a certain extent, the growth indexes in the 30 Gy dosage exposure group are better than those in control group. The Allium fistulosum L. nutrients, including the total watersoluble protein and the Vitamin C content are the highest for the 30 Gy group and the lowest in 90 Gy group. Consistent with the M1 generation, the chromosomal aberrations, micronucleus and the DNA polymorphism rate by RAPD analysis are still positive correlations with the radiation dose in M2 generation respectively. However, the overall rates decline. The result indicated that the DNA variation induced by the high energy heavy ion exposure is repaired and eliminated to a certain extent in the M2 generation.
12C6+离子束辐照紫苏干种子当代效应
武振华, 张红, #, 王新宇, 薛林贵, 牛炳韬, 赵旭
2010, 27(3): 335-340. doi: 10.11804/NuclPhysRev.27.03.335
摘要:
利用兰州重离子研究装置(HIRFL)提供的12C6+离子束辐照紫苏干种子(辐照剂量为40, 80和120 Gy, 剂量率4 Gy/min), 探讨了重离子束辐照对紫苏M1代的生物学效应。结果发现, 经不同剂量的12C6+离子束辐照后, 紫苏种子的发芽率、 发芽势、 存活率、 株高、 分枝数、单株产量和千粒重等生物学性状均发生了变化, 其中发芽势、 单株产量和千粒重随辐照剂量的提高而降低, 且有明显的剂量效应关系, 但发芽率、大田成活率、 株高和分枝数却随辐照剂量的增大, 呈现出明显的“抛物线”趋势; 紫苏幼苗根尖细胞的微核率和染色体畸变率随辐照剂量增加呈线性增加关系。 这表明: 12C6+重离子束辐照紫苏种子, 具有明显的当代损伤效应, 在本试验剂量范围内, 低剂量辐照对发芽率和成活率有促进作用。
模拟计算低能重离子注入彩棉种子的深度(已撤稿)
黄旭初, 侯 娟, 孙毅, #, 刘效勇, 井群
2010, 27(3): 341-345. doi: 10.11804/NuclPhysRev.27.03.341
摘要:
188Re内照射肝癌(H22)剂量与组织病理学评价
董峰, 郭红云, 梅澍, 牛继国
2010, 27(3): 346-350. doi: 10.11804/NuclPhysRev.27.03.346
摘要:
对建立的肝癌H22荷瘤小鼠实体瘤体局部注射188Re后, 采用CRCR-15型核素测量仪分别测定1和24 h瘤体内放射性计数, 计算188Re注入瘤体内24 h内照射吸收剂量以及放射性滞留率。188Re-S注射至肿瘤内后, 1和24 h放射性药物滞留要高于单纯188Re注射液, 188Re-S (0.1 mCi)和(0.2 mCi)组24 h瘤体内照射剂量分别为 159.78和361.52 Gy。病理学检查结果: (1) 模型组, 瘤细胞生长旺盛, 肿瘤内新生微血管丰富; (2) 治疗组, 瘤组织生长受到不同程度的抑制, 瘤细胞生长稀疏, 微血管减少, 坏死区由瘤组织外周向中心渐进。电镜观察显示, 188Re-S(0.1 mCi)治疗组可见肿瘤组织细胞凋亡小体。将188Re-S置入小肝癌H22荷瘤小鼠实体瘤局部, 在肿瘤局部形成高活度放射性聚集区, 起到靶向治疗肿瘤作用的同时, 可减少全身用量, 以降低毒副作用。The retention of the radioactive nuclide 188Re in tumor was measured in 1h and 24 h after injection of 188Re and 188ReS, respectively. The results indicate that the radionuclide remained in the tumor injected 188ReS was higher than that in the tumor of injected 188Re. Pathology test results show that in the model group one can find obviously the rapid growth of tumor cells and rich tumor angiogenesis; in the treatment groups the tumor growth is constrained in different degrees, microvascular was less and the necrosis area was spreading from the periphery to the center of the tumor. Scanning the samples of the tumors treated by 0.1 mCi 188ReS injection by using SEM shows there is a lot of apoptotic bodies of tumor cells. The injection of 188ReS into the tumor can be an effective target treatment source for therapy to decrease the radiation dosage in whole body and to reduce the toxicity side effects.
离子束辐照的碳纳米管及其物性研究
闫隆, 倪志春, I.Ahmad, 周广颖, 王雯君, 巩金龙, 周兴泰, 朱德彰
2010, 27(3): 351-356. doi: 10.11804/NuclPhysRev.27.03.351
摘要:
离子束辐照通常被认为导致材料产生缺陷, 形成无序结构, 从而破坏材料的性能。 但是, 最近利用离子束辐照碳纳米管的实验显示离子束辐照碳纳米管形成无定形的过程不能用传统的离子束辐照材料的机制来解释, 离子束辐照可导致碳纳米管形成一些自组装结构, 如无定形碳纳米结和碳纳米管连接结等。 研究还发现离子束辐照的碳纳米管薄膜在导电性和场发射性能方面都能得到明显的增强。 Ion beam irradiation is usually thought to induce defects and disordered structures in materials and then to destroy the properties of the materials. However, our recent experiments about the ion beam irradiation on carbon nanotubes(CNTs) indicate that the ion beam modification mechanism of CNTs is completely different from traditional one of bulk materials, and ion beam irradiation can lead to selforganized structures in CNTs, such as amorphous junctions and CNT junctions. Moreover, the irradiated CNTs exhibit a improved conductivity and an enhanced field emission.
低速40Ar17+离子入射金属Be表面发射的近红外光谱线和X射线谱
张颖, 张小安, #, 徐忠锋, 杨治虎, 赵永涛, 肖国青
2010, 27(3): 357-362. doi: 10.11804/NuclPhysRev.27.03.357
摘要:
用速度不同的(动能EK= 272和357 keV, 速度v=1.14×106和1.72×106 m/s)的高电荷态离子40Ar17+分别入射金属Be表面, 同时测量这种相互作用过程中产生的近红外光谱线和X射线谱。实验结果表明, 在低速范围内(速度小于玻尔速度vBohr=2.19×106 m/s), 速度较小的40Ar17+离子在到达金属的表面临界距离Rc到进入表面(2—3原子层)的进程中, 形成了较多的高激发态Ar原子, 其退激辐射较强的光谱线, 进而验证了经典过垒模型。
The highly charged ion 40Ar17+ (kinetic energy EK=272 keV, velocity v=1.14×106 m/s and EK=357 keV, v=1.72×106 m/s) impacts on the surface of metal Be, and the atomic infrared light line and Xray spectrum are simultaneously measured. The experimental results show that in the low velocity region (less than vBohr), the highly charged ion with smaller velocity from a critical distance Rc to penetrate into the bulk formed more multipleexcited Ar atoms and the spectrum intensities of decay radiation are greater, which verifies the classical over the barrier model.