反射干涉光谱法测量固体薄膜的光学常数和厚度

本文报道一种简单的方法,从平原介质薄膜的反射干涉光谱来计算薄膜的光学常数和厚度。当一束光照射在基板上的介质膜上时,由于膜上下界面反射光的相干,会使反射光谱的曲线有一定的波动。我们对反射相干光谱进行理论分析,给出计算公式,从测量曲线中的实验值得出薄膜的光学常数ｎ、ｋ以及厚度等参数。此种方法简单可行,而且易于编程处理。     

兰姆波在搭接焊缝上的反射和透射

采用数值模拟方法和实验研究了兰姆波在搭接焊缝上的反射和透射。数值模拟了频率500 kHz的兰姆波S0与.A0模态,分别在2 mm厚不锈钢板上的不同宽度搭接焊缝模型上的反射和透射,并计算了相应的反射系数和透射系数。发现:当搭接焊缝宽度小于4 mm时,S0模态的反射系数和焊缝宽度具有近似的线性关系,而焊缝余高和两板之间的间隙对S0模态反射系数的影响很小。基于兰姆波S0模态反射系数与焊缝宽度的线性关系。提出了通过测量S0模态反射系数快速测量搭接焊缝宽度的方法。实验测得的2 mm厚不锈钢板上不同宽度搭接焊缝对500 kHz的入射兰姆波S0模态的反射系数,验证了上述线性关系,说明了可用兰姆波反射回波测量搭接焊缝宽度。     

Viscosity and Diffusion Effects at the Boundary Surface of Viscous Fluid and Thermoelastic Diffusive Solid Medium

This paper concentrates on the wave motion at the interface of viscous compressible fluid half-space and homogeneous isotropic, generalized thermoelastic diffusive half-space. The wave solutions in both the fluid and thermoelastic diffusive half-spaces have been investigated; and the complex dispersion equation of leaky Rayleigh wave motion have been derived. The phase velocity and attenuation coefficient of leaky Rayleigh waves have been computed from the complex dispersion equation by using the Muller's method. The amplitudes of displacements, temperature change and concentration have been obtained. The effects of viscosity and diffusion on phase velocity and attenuation coefficient of leaky Rayleigh waves motion for different theories of thermoelastic diffusion have been depicted graphically. The magnitude of heat and mass diffusion flux vectors for different theories of thermoelastic diffusion have also been computed and represented graphically.     

银盐干板的皱缩控制及其在彩色反射全息上的应用

分析了影响全息干板银盐乳胶在处理过程中收缩的几个因素,并通过实验,找出了在拍摄及处理体积反射全息图过程中,曝光量、漂白液温度及脱水的方式对乳胶收缩影响的规律.在此基础上提出控制乳胶的收缩,即控制反射全息图衍射波长的方法,从而达到彩色反射全息图的实现.实验结果表明该方法做出的全息图效果良好.     

Dynamical Analysis and Exact Solutions of a New (2+1)-Dimensional Generalized Boussinesq Model Equation for Nonlinear Rossby Waves*

In this paper, we study the higher dimensional nonlinear Rossby waves under the generalized beta effect. Using methods of the multiple scales and weak nonlinear perturbation expansions [Q. S. Liu, et al., Phys. Lett. A 383 (2019) 514], we derive a new $(2+1)$-dimensional generalized Boussinesq equation from the barotropic potential vorticity equation. Based on bifurcation theory of planar dynamical systems and the qualitative theory of ordinary differential equations, the dynamical analysis and exact traveling wave solutions of the new generalized Boussinesq equation are obtained. Moreover, we provide the numerical simulations of these exact solutions under some conditions of all parameters. The numerical results show that these traveling wave solutions are all the Rossby solitary waves.     

苹果可溶性固形物和糖酸比可见/近红外漫反射与漫透射在线检测对比研究

可溶性固形物和糖酸比是苹果内部品质主要评价指标之一。为此进行苹果糖酸比和可溶性固形物可见/近红外漫反射和漫透射对比检测研究。180个冰糖心和红富士样品被分成建模集和预测集(136∶44),分别用于建立偏最小二乘模型和验证模型的预测能力。在运动速度5个/秒时,采集了冰糖心和红富士两种样品的可见近红外光谱。漫反射和漫透射可见近红外光谱经多元散射校正、标准正态变量变换、基线校正等预处理后,建立了偏最小二乘回归模型。未参与建模的44个样品用于评价模型的预测能力,经比较,漫透射检测方式优于漫反射检测方式,主要因为漫透射检测方式能更有效地克服杂散光。可溶性固形物模型预测相关系数达到0.936,预测均方根误差为0.476°Brix;糖酸比模型预测相关系数达到0.785,预测均方根误差为10.94。研究结果表明： 应用可见/近红外漫透射光谱技术,可实现苹果可溶性固形物和糖酸比在线检测。为大宗水果内部品质分选提供了技术支持和参考依据。     

静电势能模型对类水滑石结构与性能的理论研究

采用晶体学理论建立类水滑石静电势能模型,对由20层且每层2107个阴离子组成的镁铝类水滑石超分子体系中层间阴离子所受的静电势能进行理论计算．研究结果表明,调变层板金属离子摩尔比影响层板电荷密度与层间阴离子间距,计算得到的阴离子静电势能值与其热稳定性相一致:插层阴离子的电荷与尺寸不同直接影响阴离子的势能大小．     

循环流化床气固曳力模型

气固曳力是稠密气固两相流动,尤其是垂直流动中的主要作用力,相应的模型也是数值模拟中准确描述气固两相运动的关键.为了解决现有经验或半经验模型的普适性问题,合理描述流动中经常发生的颗粒团聚现象及其对气固曳力的影响,从理论分析入手,运用最小能量的概念,将传统的CFD方法与宏观的系统分析方法相结合,建立了一个新的计及颗粒团聚效应的气固曳力理论模型.与现有模型相比,新模型不仅具有相同的函数变化关系,可合理地描述气固两相相互作用的物理过程,而且避免了以往经验系数不准确导致的各种误差,为稠密气固两相流动的数值描述提供了重要依据.     

随机级联模型的连续标度行为

将传统的阶乘矩统计方法推广到分割数或相空间元胞大小连续变化的情形,发现以往元胞大小分立变化的随机级联α模型存在＂链条效应＂,没有连续的标度率.考虑到实验过程及实际测量情况,对模型进行了切合实际的改进,让相空间的大小和位置随机起伏.这样得到的分形体,在相空间范围的起伏足够大时,有较好的标度不变性.能达到这一要求的相空间范围起伏的临界值,对模型参数α不敏感.用Monte Carlo模拟证明了,相空间范围的起伏对模型的反常标度指数影响不大.     

The semileptonic form factors of B and D mesons in the Quark Confinement Model

The form factors of the weak currents, which appear in the semileptonic decays of the heavy pseudoscalar mesons are calculated within the quark confinement model by taking into account, for the first time, the structure of heavy-meson vertex and the finite quark mass contribution in the heavy-quark propagators. The results are in quite good agreement with the experimental data. Received: 9 June 2000 / Accepted: 15 August 2000     

F－L模型的状态方程与退禁闭相变图象

用温度场论方法计算了Ｆ－Ｌ模型在有限温度和密度下的状态方程，分析了压强对净重子数密度的等温线．结果表明，在平均场近似下，Ｆ－Ｌ模型所给出的退禁闭相变为一级相变．     

The Analytical Parametrization of Fusion Barrier by Using the Skyrme Energy-Density Function Model

Using the skyrme energy density formalism, a pocket formula is introduced for barrier heights and positions of 95 fusion reactions (48 ≤ Z_PZ_T ≤ 1520) with respect to the charge and mass numbers of the interacting nuclei. It is shown that the parameterized values of RB and VB are able to reproduce the corresponding experimental data with good accuracy. Moreover, the absolute errors of our formulas are less than those obtained using the analytical parametrization forms of the fusion barrier based on the proximity versions. The ability of the parameterized forms of the barrier heights and its positions to reproduce the experimental data of the fusion cross section have been analyzed using the Wong model.     

电磁波在相对论稀薄电离波面上的反射角和透射角

对电磁波与相对论稀薄电离波面相互作用产生的反射角和透射角进行了研究，首先在波面参考系中根据电磁波在固定边界上的相位匹配条件，确定电磁波在静止电离波面上的反射角和透射角，并利用波矢量和频率和相对论变换，导出了在实验室参考系中相应的反射角和透射角的表达式，最后对所得的结果作了进一步的讨论。     

Two-dimensional polymer networks at a mixed boundary: Surface and wedge exponents

We provide general formulae for the configurational exponents of an arbitrary polymer network connected to the surface of an arbitrary wedge of the two-dimensional plane, where the surface is allowed to assume a general mixture of boundary conditions on either side of the wedge. We report on a comprehensive study of a linear chain by exact enumeration, with various attachments of the walk's ends to the surface, in wedges of angles and , with general mixed boundary conditions. Received: 20 October 1997 / Accepted: 13 May 1998     

Associated Production of Scalars and New Gauge Bosons from a Little Higgs Model at the LHC

The littlest Higgs model with T-parity （LHT model） predicts the existence of the T-odd scalars （Φ^±, Φ^0, and Φ^P）. We consider the production of these new particles associated with T-odd gauge bosons at the Large Hadron Collider （LHC）. It is found that the partonic process qq^1 →Φ^＋ BH can generate a number of the characteristic signal events with a charged lepton and large missing energy at the LHC.     

模拟钻地弹的设计与实验研究

 对钻地弹的弹体材料、弹体参数、气动性能、侵彻过载和侵彻深度等问题进行了研究。在此基础上，设计了模拟钻地弹，并进行了外场试验，试验取得了成功，且得到一些有益的结论。     

The Wigner Band Random Matrix Model: Studied from the View Point of a Generalization of Brillouin- Wigner Perturbation Theory

The Wigner band random matrix model is studied by making use of a generalization of Brillouin-Wigner perturbation theory. Energy eigenfunctions are shown to be divided into perturbative and nonperturbative parts. A relation between the average shape of eigenstates and that of the so-called local spectral density of states (LDOS) is derived by making use of some properties of energy eigenfunctions drawn from numerical results. Several perturbation strengths predicted by the perturbation theory are found to play important roles in the variation of the shape of the LDOS with perturbation strength.     

典型有机发光二极管中载流子传输和复合模型

提高载流子复合效率是改善有机发光二极管(OLEDs)发光效率的重要方法。采用真空热蒸发成膜法制作了典型双层结构的OLEDs(ITO/TPD/Alq₃/Al)。二极管的性能测试结果表明器件的电流-电压关系与Fow ler-Nordheim场发射载流子注入理论符合得较好。以Fow ler-Nordheim场发射载流子的隧穿注入理论为基础,对OLEDs的电流进行理论分析和数学推导,建立典型双层结构有机发光二极管中载流子传输、复合的理论模型。以此模型为依据,对载流子注入复合进行理论分析,探究载流子注入复合的效率的表达式。在外加电压和器件材料一定下,得出了载流子复合效率与阳极区一侧积累的空穴面密度和阴极区一侧积累的电子面密度的关系表达式。     

两相壁面射流PDF方程有限分析方法及数值模拟

提出求解位置-速度相空间中高维两相流PDF(probability density function)方程的有限分析方法,将位置-速度相空间颗粒PDF方程约化到速度空间,并解析求解,颗粒的位置PDF用轨道方法求解.对壁面射流两相流动进行数值模拟,并与颗粒雷诺应力轨道方法进行比较计算,结果优于颗粒雷诺应力轨道方法.