超重核294118和291116及其α衰变链上各核素半衰期的研究

运用推广的液滴模型（GLDM）确定了超重核294118和291116及其α衰变链上各核素的衰变势垒, 采用量子力学中的WKB方法计算α衰变中的势垒穿透几率, 对该链上各原子核的α衰变半衰期进行了研究。 此外, 还利用Royer公式对该链上各原子核的α衰变半衰期进行了计算。 结果表明, GLDM 考虑亲和能与Royer公式给出的α衰变半衰期与超重核区的实验值符合很好, 验证了GLDM和Royer公式在超重核区的适用性,可以用来预测超重核的半衰期。 最后, 预言了Z=118 和116 同位素链上各核素的半衰期, 结果表明, 在Z=118和116中存在α衰变长寿命同位素, 这需要实验上的检验。The α decay potential barrier of the newly synthesized superheavy nuclei starting from 294118 and 291116 have been determined and their half lives have been studied with the Generalized Liquid Drop Model(GLDM) connected with WKB approximation and Royer’s formulae．The α decay half lives of the nuclei belonging to the superheavy nuclei starting from 294118 and 291116 have been calculated．The calculated results are in agreement with the experimental data, which show that the α decay half lives of superheavy nuclei with the GLDM and Royer’s formulae can be applied in the studying on superheavy nuclei successfully．Finally, the half lives of Z=118 and 116 isotopes have been predicted, and the results suggest there may be some long lived superheavy nuclei for α decay in those isotopes.     

超重核合成进展

介绍了超重核合成的历史和现状,对现有的超重核合成的实验情况和理论模型做了评述,指出了在国内利用现有设备和放射性核束装置开展超重核合成可能的方案。     

乙醇超重力MVR热泵精馏系统仿真及优化研究

针对超重力MVR热泵精馏模拟研究少的现状,对于乙醇-水这一典型非理想物系,基于Aspen Plus中重力场精馏塔非平衡级模型,通过编译和调用体积传质和相界面积参数Fortran子程序,构建了超重力精馏塔数学模型.在变回流比和进料位置两组工况下,进行了超重力MVR热泵精馏系统仿真模拟,将仿真结果与文献中实验结果进行了对比...     

超重核研究实验方法的历史和现状简介

简单介绍了超重核合成的历史,详细讨论了目前超重核合成最成功的技术路线,包括产生方法、分离手段以及探测技术,并就各种技术的优缺点进行了比较.探讨了目前超重核研究所面临的困难以及介绍了国际上几个主要相关实验室的研究动态,并对超重核研究的发展趋势做了简单展望. The history of the synthesis of the transuranium nuclei is briefly introduced. The most successful techniques currently used for synthesizing super heavy nuclei are surveyed and discussed in detail. The drawbacks and the problems for reaching the stability island of super heavy nuclei with the techniques currently used are discussed. The present status and perspectives of the super heavy nuclei research at different laboratories are also introduced. Finally, a brief prospect on the trends...     

Systematic Study of Stability of Super Heavy Nuclei

A systematic overview on the characteristics of super heavy nuclei from Z=101 to Z=130 based on thedata by P. Moeller et al. is presented. The nuclei which have the biggest mean binding energy in each of their isotope chain show systematic regular behavior, indicating that the mean binding energy is a good criterion to classify super heavy nuclei by their stabilities. Further investigation on the nuclear data at and after Z=127 has been suggested.     

纳米硫化锌的制备及光谱分析

采用超重力反应结晶法制备了纳米硫化锌粒子,并通过透射电子显微镜(TEM)、X射线粉末衍射仪(XRD)、X射线光电子能谱仪(XPS)、傅里叶红外光谱仪(FTIR)、紫外-可见光分光光度计(UV-Vis)和X射线能谱仪(EDX)对纳米硫化锌的形貌、结构、组成和光谱性能进行了细致分析。结果表明：超重力反应结晶法制备的纳米硫化锌粒子为球形,平均粒径为42 nm;XRD图谱表明纳米硫化锌呈现较好的闪锌矿晶型; XPS能谱表明纳米硫化锌的S(2p)的电子结合能为162.6 eV,Zn的2p_3/2,2p_1/2的电子结合能分别为1021.4, 1044.6eV。红外光谱研究表明纳米硫化锌在400～4 000cm-1范围内具有良好的红外透过率。紫外-可见光谱研究发现纳米硫化锌在200～340nm的紫外区域有较强的吸收,其禁带宽度为3.57eV。EDX能谱表明该法制备的纳米硫化锌具有较高的纯度。     

关于重核强阻尼反应的研究

讨论了重核碰撞形成巨复合体系破裂的强阻尼反应产生超重核的问题。 评述了两种主要的理论模型: 唯象的多维朗之万模型和本课题组发展的微观输运理论模型。 概括阐述了微观输运理论研究反应 197Au+197Au , 238U+238U和244Pu+244Pu等的主要结果。 给出了反应中产生的超重碎块的几率与入射能的关系, 复合体系和超重碎块的衰变机制以及所形成的超重碎块的结合能和形状的分布。 In this paper, the possibility of producing superheavy fragments through strongly damped reactions in very massive nuclear collisions is investigated. Two theoretical models, which are the phenomenologically multi dimensional Langevin equation model and improved quantum molecular dynamics model developed recently by our group, are briefly reviewed. The dependence of the production probability of superheavy fragments on the incident energy, the decay mechanism of the composite systems and superheavy fragments, and the distributions of the binding energy and shapes of superheavy fragments are iscussed for reactions of 244Pu+244Pu, 238U+238U, 197Au+197Au based on the improved quantum molecular dynamics model.     

重离子碰撞复合体系碎化产生超重核可能性的探讨

讨论了通过重核碰撞形成的复合体系破裂产生超重核的问题。评述了两种主要的理论模型:即早期发展的在碎化理论框架下的量子涨落理论和本课题组尝试发展的微观输运理论模型。概括阐述了微观输运理论研究^197Au＋^197Au,^238U＋^238U和^244Pu＋^244Pu等反应的主要结果,即反应中产生的超重碎块的几率与入射能的关系,复合体系和超重碎块的衰变机制以及所形成的超重碎块的结合能和形状的分布。In this paper, the possibility of producing superheavy fragments through composite system breaking up in massive nuclear reactions is investigated. Two main theoretical models, which are the quantum fluctuations with in the fragmentation theory developed at 1980＇s and improved quantum molecular dynamics model developed recently by our group, are briefly reviewed. The dependence of the production probability of superheavy fragments on the incident energy, the decay mechanism of composite system and superheavy fragments, and the distribution of binding energy of Superheavy fragments are discussed for reactions of ^244Pu＋^244Pu, ^238U＋^238U, 197Au＋^197Au based on the improved quantum molecular dynamics model.     

宁波市中小学生超重和肥胖的现状调查与分析

为了解宁波市中小学生肥胖的发生率情况, 以2010年浙江省学生体质调研数据为基础, 对宁波市3085名中小学生进行超重和肥胖的研究. 结果显示: 城市男生的超重检出率非常显著地高于农村男生, 而真正肥胖的检出率却呈现出农村高于城市的现象; 女生超重检出率没有发现城乡差异, 肥胖检出率农村依旧高于城市; 宁波市中小学生中男生超重检出率显著高于女生(P<0.01), 而肥胖检出率没有明显的性别差异; 在分年龄段比较中, 还发现这种超重和肥胖的性别差异以9~11岁和14~17岁两个年龄范围为典型. 结论是农村学生的肥胖检出率超过了城市学生, 女生超重检出率基本持平, 说明超重和肥胖的现象已经开始步入乡村. 超重和肥胖的高发年龄段与全国调研数据接近, 但男女生超重和肥胖检出率的明显差异集中体现在9~11岁和14~17岁年龄段, 由此可见, 青春前期和青春期是超重和肥胖的高危时期.     

相对论平均场模型对奇-偶超重核基态性质的系统研究

在形变的相对论平均场模型下,采用NL-Z2,TMA两套参数对质子数为103—109的奇–偶核基态性质进行了系统的计算,并将理论计算的结合能、α衰变能与已知的实验数据进行对比,发现两者符合得很好,肯定了相对论平均场模型对超重核研究的可靠性,同时对未知核素基态性质的计算结果可供未来的超重核理论和实验研究参考.