Measurement of hyperfine structure and isotope shifts in the 580.56nm line of 142－145,146,148,150Nd+

Isotope shifts and hyperfine spectrum of singly ionized neodymium ion was measured by collinear fast-ion-beam laser spectroscopy. The hyperfine A constants and B constants are obtained for the (23230)9/2^0 level and 4f^45d ^6K9/2 level, respectively. The optical isotope shifts between seven isotopes in the 580.56 nm of^142-145,146,148,150Nd^ line are determined. The configuration admixtures for (23230)9/2^0 level were quantitatively analysed to be 4f^46p, 4f^35d^2, and 4f^35d6p with mixing coefficients of 67%, 5%, and 28%, respectively.     

谈谈正确理解电子电路中有关约束条件的重要性

全面考虑电路的约束条件，对于正确地分析电子电路是非常重要的。本文通过具体的应用实例，强调正确地、全面地理解约束条件在电子电路分析中的重要性。     

液晶显示器的替代ODS清洗技术研究

液晶显示器行业目前一般采用ODS溶剂清洗．对一种新型水基替代ODS清洗技术进行了研究。利用X射线光电子谱的测试方法，比较用两种清洗技术清洗过的样品，结果表明，新型替代清洗技术优于传统ODS清洗技术．     

三株红球菌降解苯酚的研究

从山西印染厂活性污泥中分离出三株降解苯酚的红球菌,它们均能以苯酚作为生长的唯一碳源,20小时之内可将500ppm的苯酚去除90%以上;其降解苯酚的最适pH为7.0—9.0;降解苯酚的最适温度分别为:R(?),30—35℃; R(?),30—35℃,R(?),25—30℃。培养48—72小时降解苯酚的最高浓度分别为:R(?)为1400ppm,R(?)为1600ppm,R(?)为1100ppm;耐酚极限均为2000ppm。氰化物对它们降解酚苯有抑制作用。     

Dynamical Evolution of Globular Clusters in the Galaxy

Given the initial conditions of spatial density distribution, velocity distribution and mass function, the dynamical evolution of globular clusters in the Milky Way is investigated in details by means of Monte Carlo simulations.Four dynamic mechanisms are considered: stellar evaporation, stellar evolution, tidal shocks due to both the disc and bulge, and dynamical friction. It is found that stellar evaporation dominates the evolution of low-mass clusters and all four are important for massive ones. For both the power-law and lognormM initial clusters mass functions, we can find the best-fitting models which can match the present-day observations with their main features of the mass function almost unchanged after evolution of severM Gyr. This implies that it is not possible to determine the initial mass function only based on the observed mass function today. The dispersion of the modelled mass functions mainly depends on the potential wells of host galaxies with the almost constant peaks,which is consistent with current observations.     

铁路沿线旅游规划若干问题研究

本文根据铁道部《先行计划》所规定的战略目标,通过分析铁路部门参与旅游业发展的必要性和可行性,提出了制订铁路沿线旅游规划应循的原则。在此基础上,重点探讨了规划的主要内容:铁路沿线地区基本条件的调查、分析与评价;旅游列车专项服务的内容与方法;铁路部门参与地方旅游业建设的内容与途径;铁路系统内部的协作;旅游专线和专列的合理布局等。对于规划的编制方法,本文也作了简单的介绍。     

Effect of high temperature band gap of GaN annealing on strain and nanoparticles

<正>Black-coloured GaN nanoparticles with an average grain size of 50 nm have been obtained by annealing GaN nanoparticles under flowing nitrogen at 1200℃for 30 min.XRD measurement result indicates an increase in the lattice parameter of the GaN nanoparticles annealed at 1200℃,and HRTEM image shows that the increase cannot be ascribed to other ions in the interstitial positions.If the as-synthesised GaN nanoparticles at 950℃are regarded as standard,the thermal expansion changes nonlinearly with temperature and is anisotropic;the expansion below 1000℃is smaller than that above 1000℃.This study provides an experimental demonstration for selecting the proper annealing temperature of GaN.In addition,a large blueshift in optical bandgap of the annealed GaN nanoparticles at 1200℃is observed,which can be ascribed to the dominant transitions from the C（Γ₇） with the peak energy at 3.532 eV.     

基于多主体建模方法研究空间市场效率的影响

基于多主体建模的方法通过建立记忆叠加模型,研究信息对空间市场效率的影响．模型模拟发现,个体的朋友数量和视野半径对市场聚集度、简单社会熵和市场交易成功率产生显著影响,从而影响市场效率．     

气流槽聚型紧密集聚纺力矩传递分析

为了探讨气流槽聚型紧密集聚纺纱系统集聚区内的力矩传递,首先分析了集聚区内纺纱张力矩和气流力矩的传递过程,然后分析了纱线自身回转产生的扭矩与纺纱张力矩和气流力矩的关系.研究结果表明:影响力矩传递的主要参数有纺纱张力、吸气负压值等;纺纱张力矩与气流力矩决定捻度是否会越过纤维束与凹槽底部的初始接触点上传至前钳口;适当提高吸气负压值可以缓解纺纱张力.     

线性调频信号激励过阻尼双稳系统的随机共振现象研究

线性调频信号是工程中常见的一种信号, 由于其为非周期信号, 无法以频域信噪比作为衡量其是否产生随机共振的测量手段, 故鲜有文献研究以线性调频信号为激励信号的随机共振现象. 本文利用线性调频信号在最优分数阶Fourier变换域上的能量聚集性, 首次提出以最优分数阶Fourier变换域上定义的信噪比作为测量手段, 研究了线性调频信号叠加高斯白噪声激励过阻尼双稳系统的随机共振现象, 且发现了以线性调频信号为激励信号时产生的新现象, 即随着信号频率的增大, 随机共振将逐渐减弱, 并给出了合理的解释.仿真的结果与理论分析一致, 验证了本文所提出方法的有效性. 关键词： 线性调频信号 分数阶Fourier变换 随机共振