振动合成在气垫导轨上的验证

晶格中原子的集体振动——声子与晶格的热力学性质密切相关。它是凝聚态物理中的重要内容并具有广泛的应用。由于介绍量子化的声子需要较多的基础知识,目前很少在本科教学中展示该内容。本文从经典物理的角度出发,通过气垫导轨实验来演示滑块的集体振荡,验证了任一种振动均是由基振动线性叠加而成,这一实验在本科教学中可帮助学生理解"合成、叠加、耦合"等现代物理学概念。     

聚氧乙烯功能基复合修饰聚氨酯合成及其血液相容性研究（Ⅱ）—聚氨酯—接枝

采用以碘酸基为末端基的聚氧乙烯（PEO）接枝聚醚氨酯和氨基酸反应,将赖氨酸（Lys)和酪氨酸（Tyr)通过PEO为“间隔臂”固定在聚醚氨酯上,制备了氨基酸和PEO复合修饰的聚醚氨酯PEU－g-PEO-SO2Lys和PEU－g-PEO-SO2Tyr。通过血小板粘附试验对材料的体外抗凝血性进行 了初步评价。研究结果表明,采用具有选择性吸附纤溶酶原功能的赖氨酸和PEO复合修聚氨酯,不仅减少了材料表面血小板粘附量,而且减少了材料表面栓的形成量。     

Circular shallow spherical shells with central circular hole under simultaneous actions of arbitrary unsteady temperature field and arbitrary dynamic normal load

In this paper, under assumption that tempeature is linearly distributed along the thickness of the shell, we deal with problems as indicated in the title and obtain general solutions of them which are expressed in analytic form.In the first part, we investigate free vibration of circular shallow spherical shells with circular holes at the center under usual arbitrary boundary conditions. As an example, we calculate fundamental natural frequency of a circular shallow spherical shell whose edge is fixed (m=0). Results we get are expressed in analytic form and check well with E. Reissner’s [1]. Method for calculating frequency equation is recently suggested by Chien Wei-zang and is to be introduced in appendix 3.In the second part, we investigate forced vibration of shells as indicated in the title under arbitrary harmonic temperature field and arbitrary harmonic dynamic normal load.In the third part, we investigate forced vibration of the above mentioned shells with initial conditions under arbitrary unsteady temperature field and arbitrary normal load.In appendix 1 and 2, we discuss how to express displacement boundary conditions with stress function and boundary conditions in the case m=1.     

Probing the Energy Spectrum in the Vicinity of Dirac Points with Landau–Zener Transition

Recently a new type of experiment, i.e., Bloch oscillations of ultracold atoms in honeycomb optical potential,realized Landau–Zener transition in the vicinity of Dirac point in 2D optical lattice. We show that the slope of Dirac cone is related to the transition probability of Landau–Zener transition. Therefore, it provides a new tool to directly detect the energy spectrum in the vicinity of Dirac point. Moreover, we numerically demonstrate that our scheme is feasible and effective in a large range of the parameter of anisotropy.     

利用等厚干涉测量钢丝的杨氏模量

测量杨氏模量常采用光杠杆法进行测量。而利用等厚干涉的方法可以比光杠杆法更精确地测出钢丝形变的变化量。目前利用等厚干涉测量杨氏模量的实验中多需借助显微镜进行观察及使用电脑对图像进行处理。本文提及的实验方法既可以用电脑进行图像处理,也可以直接用肉眼观察条纹的变化,使实验变得简单易行且精度也比较高,并能满足不同层次的数据处理的需要,可以作为一项综合性实验纳入大学物理实验中。     

用干涉显微镜测量薄膜厚度的改进与分析

将干涉显微镜的应用推广到透明薄膜厚度的测量,扩展了干涉显微镜的测量范围和应用领域.基于菲涅耳公式,分析了透明薄膜界面的反射.根据白光干涉原理,利用圆形样品台的定量移动,实现了薄膜厚度的测量.     

Circular Shallow Spherical Shells with Central Circular Hole Under Simultaneous Actions of Arbitrary Unsteady Temperature Field and Arbitrary Dynamic Normal Load

In this paper,under assumption that tempeature is linearly distributed along the thickness of theshell,we deal with problems as indicated in the title and obtain general solutions of them which areexpressed in analytic form.In the first part,we investigate free vibration of circular shallow spherical shells with circularholes at the center under usual arbitrary boundary conditions.As an example,we calculate fundamen-tal natural frequency of a circular shallow spherical shell whose edge is fixed(m=0).Results we get areexpressed in analytic form and check well with E.Reissner’s[1].Method for calculating frequencyequation is recently suggested by Chien Wei-zang and is to be introduced in appendix3.In the second part,we investigate forced vibration of shells as indicated in the title under arbitr-ary harmonic temperature field and arbitrary harmonic dynamic normal load.In the third part,we investigate forced vibration of the above mentioned shells with initialconditions under arbitrary unsteady temperature