Alpha decay half-lives of heavy nuclei within a generalized liquid drop model

Theoretical α-decay half-lives of the heaviest nuclei are calculated using the experimental Q_α value. The barriers in the quasi-molecular shape path is determined within a Generalized Liquid Drop Model (GLDM) and the WKB approximation is used. The results are compared with calculations using the Density-Dependent M3Y (DDM3Y) effective interaction and the Viola-Seaborg-Sobiczewski (VSS) formulae. The calculations provide consistent estimates for the half-lives of the α decay chains of these superheavy elements. The experimental data stand between the GLDM calculations and VSS ones in the most time.     

X-ray emission from 424-MeV/u C ions impacting on selected target

The K-shell x-rays of Ti, V, Fe, Co, Ni, Cu, and Zn induced by 424-MeV/u C~(6+) ion impact are measured. It is found that the K x-ray shifts to the high energy side and the intensity ratio of Kβ/Kα is larger than the atomic data, owing to the L-shell multiple-ionization. The x-ray production cross sections are deduced from the experimental counts and compared with the binary encounter approximation(BEA), plane wave approximation(PWBA) and energy-loss Coulomb-repulsion perturbed-stationary-state relativistic(ECPSSR) theoretical predictions. The BEA model with considering the multipleionization fluorescence yield is in better consistence with the experimental results. In addition, the cross section as a function of target atomic K-shell binding energy is presented.     

非全裸氟离子与氖原子碰撞中的转移电离研究

采用位置灵敏探测和散射离子 反冲离子飞行时间技术测量了强相互作用区F2 + 和F3 + 离子与Ne原子碰撞中的转移电离截面与单电子俘获截面之比 .与Fq+ He实验结果进行了比较 ,并进行了定性讨论. The ratios of the cross-section of the transfer ionization to the single electron capture of Neon induced by F 2+ and F 3+ ions are measured by means of the time-of-flight technologie. In the present energy range, the transfer ionization C1I1 of neon can be considered as a two-step process, in which one electron is captured by projectile and another one is directly ionized, and the transfer ionization C1I2 process should be considered as a subsequent rearrangement of neon following...     

可达到和可逼近总极小点的存在性和最优性

针对积分总极值，讨论并拓展了丰满集和丰满函数的概念，研究了拟上丰满和伪上丰满函数的总极值问题. 在总极值的变差积分最优性条件下，证明了拟上丰满函数的可达到极小点和伪上丰满函数的可逼近极小点的存在性.     

层流氩等离子体射流温度的测量

 采用给水冷管状静电探针施加负偏置电压、并使探针以一定速度垂直于射流轴线扫过层流氩等离子体射流的方法,测量探针所收集到的累积离子饱和电流随侧向位置的变化,利用Abel变换推导出了局部离子饱和电流密度沿射流径向的分布;采用自制的水冷动压探针,以动态扫描法测量了射流动压沿射流径向的分布;根据局部离子饱和电流密度和射流动压的测量数据,由理论关系式推导出了等离子体射流横截面上的温度分布,同时,采用谱线相对强度法测量了等离子体射流的激发温度。结果表明：两种方法得到的等离子体射流中心温度吻合较好,所得到的射流中心温度随弧电流加大而增大的变化趋势也一致。     

湍流空气自由射流引射特性的比较研究

对商用CFD软件中的四种湍流模型给出的湍流空气自由射流引射特性计算结果进行了比较,并将采用四种湍流模型计算获得的射流引射量计算数据与文献报道的采用多孔壁技术获得的射流引射量实验数据进行了对比,结果表明：在四种湍流模型中,标准K—ε湍流模型给出的湍流空气自由射流引射规律与实验数据较好符合。本文还选用标准K—ε湍流模型对欠...     

Experimental study of cross-section ratios in the collisions of Cq＋ and oq＋（q= 1-4） on atomic helium in strong-interaction region

We have measured the cross-section ratios of helium induced by C^q+ and O^q+ (q=1-4) in an energy range from 20 keV/amu to 500 keV/amu, and obtained the two-dimensional spectra by employing the coincidence method combined with the MPA-3 data acquisition system. Hence, we obtain the ratios of total single-ionization cross-sections (SI, SC, SLSI, and DLSI), total double-ionization cross-sections (DI, DC, TI, SLDI, and DLDI) and cross-sections of every process (SI, SC, SLSI, DLSI, DI, DC, TI, SLDI, and DLDI), which induce the single-ionization and double-ionization, to the total cross sections respectively. The competitive relations between the reaction-channels and the experimental data law of each reaction-channel are revealed explicitly, and the qualitative explanations involved in those results are also presented accordingly.     

凝固浴温度对PVDF-g-PNIPAAm温度敏感膜成膜过程与性能的影响

通过自由基共聚的方法制备了聚偏氟乙烯-g-聚(N-异丙基丙烯酰胺)(PVDF-g-PNIPAAm)共聚物,采用浸没沉淀相转化法制备了PVDF-g-PNIPAAm共聚膜.采用超声时域反射法研究了不同凝固浴温度下PVDF-g-PNIPAAm的成膜动力学,并研究了凝固浴温度对膜结构与性能的影响.结果表明,在不同凝固浴温度下,...     

函数空间中总极值的R-收敛有限维逼近

应用测度序列R-收敛的新概念来描述函数空间中总极值问题解的有限维逼近,并利用变差积分途径来寻找这样的解.针对有约束问题,运用罚变差积分算法把所给问题转化为无约束问题,且给出一个非凸状态约束最优控制问题的数值例子以说明该算法的有效性.