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EFFICIENCY DYNAMICS ON SCALE-FREE NETWORKS WITH COMMUNITIES
No full textThe simple efficiency model is developed on scale-free networks with communities to study the effect of the communities in complex networks on efficiency dynamics. For some parameters, we found that the state of system will transit from a stagnant phase to a growing phase as the strength of community decreases
CONSISTENT THREE-BODY FORCE WITH BONN B POTENTIAL AND NEUTRON STAR STRUCTURE
No full textMicroscopic three-nucleon force consistent with the Bonn B two-nucleon potential is constructed, which includes Delta(1232), Roper, and nucleon-antinucleon excitation contributions. Recent results for the choice of the meson parameters are discussed. The forces are used in Brueckner calculations and the saturation properties of nuclear matter are determined. At the high densities,the nuclear equation of state and the symmetry energy are calculated. The corresponding neutron star mass-radius relations are presented
THE ISOSPIN DEPENDENCE OF THE NUCLEAR PHASE TRANSITION NEAR THE CRITICAL POINT
No full textThe experimental results reveal the isospin dependence of the nuclear phase transition in terms of the Landau Free Energy description of critical phenomena. Near the critical point, different ratios of the neutron to proton concentrations lead to different critical points for the phase transition which is analogous to the phase transitions in He-4-He-3 liquid mixtures. The antisymmetrized molecular dynamics (AMD) and GEMINI models calculations were also performed and the results will be discussed as well
Some Superconducting Magnets at IMP
No full textSome superconducting magnets research at IMP (Institute of Modern Physics, CAS, Lanzhou) will be described in this paper. Firstly, a superconducting electron cyclotron resonance ion source (SECRAL) was successfully built to produce intense beams of highly charged heavy ions for Heavy Ion Research Facility in Lanzhou (HIRFL). An innovation design of SECRAL is that the three axial solenoid coils are located inside of a sextupole bore in order to reduce the interaction forces between the sextupole coils and the solenoid coils. For 28 GHz operation, the magnet assembly can produce peak mirror fields on axis of 3.6 T at injection, 2.2 T at extraction, and a radial sextupole field of 2.0 T at plasma chamber wall. Some excellent results of ion beam intensity have been produced and SECRAL has been put into operation to provide highly charged ion beams for HIRFL since May 2007. Secondly, a super-ferric dipole prototype of FAIR Super-FRS is being built by FCG (FAIR China Group) in cooperation with GSI. Its superconducting coils and cryostat is made and tested in the Institute of Plasma Physics (IPP, Hefei), and it more 50 tons laminated yoke was made in IMP. This super-ferric dipole static magnetic field was measured in IMP, it reach to the design requirement, ramping field and other tests will be done in the future. Thirdly, a 3 T superconducting homogenous magnetic field solenoid with a 70 mm warm bore has been developed to calibrate Hall sensor, some testing results is reported. And a penning trap system called LPT (Lanzhou Penning Trap) is now being developed for precise mass measurements
The Application of Toolkit of Optimization in Designs of Accelerator Magnets
No full textThe traditional design of accelerator magnet usually involves many time consuming iterations of the manual analysis process. A software platform to do these iterations automatically is proposed in this paper. In this platform, we use DAKOTA (a open source software developed by Sandia National Laboratories) as the optimizing routine, which provides a variety of optimization methods and algorithms, and OPERA (software from Vector Fields) is selected as the electromagnetic simulating routine. In this paper, two examples of designs of accelerator magnets are used to illustrate how an optimization algorithm is chosen and the platform works
Preparation and Optical properties of one dimensional nanostructure in etched ion-track template
No full text一维纳米材料，包括纳米线、纳米管、纳米棒等，因其奇异的物理化学性能，引起
了科研工作者的广泛关注。重离子径迹模板法在一维纳米材料有序阵列体系的制备及性
能表征方面具有独特的优势。
本论文主要研究内容包括重离子径迹模板的制备，导电聚吡咯纳米线/管阵列的制
备和光吸收性能研究， 以及 Au 纳米线/Cu 纳米线或管异质结构的制备及其表面等离子体
共振性能研究。
利用重离子辐照技术结合化学蚀刻方法，制备了不同孔径、不同面密度的聚碳酸酯
模板，模板的孔道均呈圆柱状，且孔径具有良好的单分散性。
利用重离子径迹模板，结合电化学沉积技术，制备出了不同直径的聚吡咯纳米线和
纳米管阵列。场发射扫描电子显微镜和透射电子显微镜照片结果显示，纳米线和纳米管
表面光滑，粗细均匀，均呈规则的圆柱状。通过对嵌在模板里的聚吡咯纳米线和纳米管
阵列进行紫外-可见-近红外光谱分析， 发现随着纳米线和纳米管直径增加， 吸收峰展宽，
且峰位发生了红移。另外，本文还对聚吡咯纳米线和纳米管的生长机理进行了研究。
利用聚碳酸酯模板结合电化学方法可控制备了Au纳米线/Cu纳米线和Au纳米线/Cu
纳米管两段异质结构。透射电子显微镜结果表明，该异质结构在 Au 和 Cu 两相交界处有
明显的界面。初步研究了两段异质纳米结构的生长机制。对镶嵌在 PC 模板里的异质纳
米结构阵列样品的两面分别做了 X 射线衍射（XRD）分析，确定了样品中 Au 相和 Cu 相
同时存在。Au/Cu 两段异质纳米结构阵列的紫外-可见光谱分析表明，其横向表面等离子
体共振峰可能是 Au 和 Cu 两段异质纳米结构表面自由电子协同振动的结果
Studies on Screening and Mutation Mechanism of Yeast Saccharomyces cerevisiae after Heavy Ion Beam Irradiation
No full text目的：
利用重离子束辐照诱变酵母，筛选具有优良发酵能力并稳定遗传的酵母菌
株，使用甜高粱汁作为发酵原料并优化酵母乙醇发酵工艺；用分子生物学方法分
析突变菌株的基因DNA损伤、变异情况以及蛋白表达的差异，探讨可能的诱变机
理。
材料与方法：
利用兰州重离子研究装置（HIRFL）加速的碳离子束和氖离子束辐照酿酒酵
母，测定辐照后酵母的存活曲线及突变菌株的生长曲线；使用红四氮唑（TTC）
培养基作为指示培养基初筛出正突变菌株，然后通过摇瓶发酵实验复筛出较高发
酵产乙醇能力酿酒酵母，并进行稳定性传代实验；筛选出的优良酵母菌株使用
10L-100L发酵罐，以甜高粱汁作为原料进行发酵实验；使用脉冲场凝胶电泳
（PFGE） 、 随机扩增多态性 （RAPD） 等方法检测酵母基因在辐照后的损伤及DNA
多态性；通过扩增和测序分析突变菌株乙醇脱氢酶（ADH）同工酶基因序列，对
基因突变位点进行分析；使用蛋白质印迹（western blot）的方法分析突变菌株与
原始菌株ADH1表达的差异性。
结果：
1. 通过不同剂量的碳离子束和氖离子束辐照筛选出数株具有优良发酵能力的酵
母菌株，其中以C03A为最佳，在10L发酵罐小试实验中，C03A发酵速率相对
原始菌株高， 36h发酵完成， 比原始菌株 （48h） 缩短12h； 发酵产酒率达到13.2%
（v/v） ，比原始菌株提高了13.79%。
2. 酵母半致死剂量约为50Gy， 生长曲线表明突变菌株比原始菌株生长速率略高；
PFGE实验表明随着剂量增大DNA双链断裂（DSB）逐渐增多；RAPD实验表
明不同剂量辐照的酵母突变菌株DNA多态性非常明显。
3. 通过测定突变菌株和原始菌株乙醇脱氢酶（ADH）同工酶全序列并比对分析，
发现重离子辐照对酵母DNA突变包括碱基转移，碱基替换，碱基插入和碱基
缺失等，其中碱基替换最多，约占84.9%。
4. 乙醇脱氢酶差异性表达表明，乙醇脱氢酶表达量的增加及活性的提高一定程
度上提高了突变菌株发酵产生乙醇的能力。
结论：
1. 通过不同剂量的碳离子束和氖离子束辐照筛选出数株具有较高发酵产乙醇能
力并且遗传稳定的优良酵母菌株，这表明重离子束辐照是一种非常有效的筛
选工业微生物的方法，具有很高的诱变效率。
2. 酵母细胞通过重离子束辐照处理以后，致死效应和酵母基因组DNA 损伤明
显。
3. 重离子束辐照能导致酵母DNA出现碱基转移，碱基替换，碱基插入和碱基缺
失等，这些突变可能导致菌株可遗传性状的改变。重离子束辐照能导致功能
基因活性和表达出现差异，从而改变酵母菌株性状，结合工艺优化可以筛选
出更多高效的优良酵母菌株。
4. 乙醇脱氢酶的含量和活性是影响突变菌株和原始菌株发酵能力的差异重要因
Preparation Polypropylene Microporous Membranes by Swift Heavy Ion Irradiation and Application in Li-ion Battery
No full text本论文首先研究了辐照参数和蚀刻参数对聚丙烯（PP）微孔膜制备过程的影响，这
些参数包括入射离子种类、紫外光敏化时间、蚀刻温度、蚀刻液浓度配比等。在此基础
上，制备出孔径从 270 nm到1.61 μm的 PP 微孔膜。对膜的表面和断面形貌进行表征，
结果显示微孔膜的孔径大小及空间分布均匀，孔道上下贯通，形状接近圆柱形。将制备
的PP微孔膜用作锂离子电池隔膜，理论推导了隔膜的孔隙率公式和离子电导率公式。用
电化学交流阻抗谱（EIS）测定浸满电解液的隔膜的离子电导率，讨论了微孔参数对隔膜
离子电导率的影响，并与商用隔膜进行比较。分析表明辐照剂量和孔径大小均会影响膜
的孔隙率和离子电导率，选择合适的辐照剂量和蚀刻时间，可以制备出孔隙率和离子电
导率均满足商用要求的PP微孔膜
Structure of 6He with fully correlated Gaussian basis
No full text原子核的晕现象自从发现起，就引起了广泛的注意。到目前为止，实验上
已经发现了越来越多具有晕结构的原子核。理论物理学家也十分关注原子核这
一奇特现象，并试图提出各种理论模型来解释。本文用完全关联高斯波包法与
变分法对6He的团簇结构进行了研究。
本文先简单介绍了完全高斯波包法的基本概念，包括相对坐标系、反对称化
算符等。然后详细介绍了如何利用完全高斯波包来构造变分法所需的试探波函
数。变分法中，哈密顿量和态叠加矩阵元的算法非常重要。文章对这部分作了
较为详细的说明。试探波函数中包括了很多的参数，而这些参数直接影响了计
算的速度。为了计算方便，文章还采用了随机变分法。
文章最后计算6He的束缚能级，半径，还有6He中质子和中子的密度分布以及
各自的半径并与其他模型和实验作了比较，以此得出完全关联高斯波包法是一
种研究原子核団簇结构可行的方法