Non-contact method for measuring solution concentration using surface plasmon resonance apparatus and heterodyne interferometry

A simple non-contact method is proposed for measuring the concentration of solutions. Using the significant phase difference between p- and s-polarizations of the reflected light of a surface plasmon resonance apparatus, the variation in the phase difference, which is caused by a variation in the concentration of a test solution, can be accurately measured by common path heterodyne interferometry. Then, by substituting the corresponding variation in the incident angle of light at the base of the SPR prism in a specially derived equation, the concentration of the test solution can be determined. The validity of this method was demonstrated experimentally. This method is characterized by the advantages of the device having a simple non-contact structure; it being easy to operate; and its high accuracy, stability, and resolution.     

On the dynamic instability of nanowire-fabricated electromechanical actuators in the Casimir regime: Coupled effects of surface energy and size dependency

Herein, the dynamic pull-in instability of cantilever nanoactuator fabricated from conductive cylindrical nanowire with circular cross-section is studied under the presence of Casimir force. The Gurtin–Murdoch surface elasticity in combination with the couple stress theory is employed to incorporate the coupled effects of surface energy and size phenomenon. Using Green–Lagrange strain, the higher order surface stress components are incorporated in the governing equation. The Dirichlet mode is considered and an asymptotic solution, based on the path integral approach, is applied to consider the effect of the Casimir attraction. Furthermore, the influence of structural damping is considered in the model. The nonlinear governing equation is solved using analytical reduced order method (ROM). The effects of various parameters on the dynamic pull-in parameters, phase planes and stability threshold of the actuator are demonstrated.     

Coupling effects of initial stress and scale characteristics on the dynamic behavior of bioliquid-filled microtubules immersed in cytosol

In this paper, an analytical method is presented to solve the influence of initial stress and scale effect on the dynamic behaviors of bioliquid-filled microtubule, utilizing the non-local elastic theory containing long-range forces among atoms and the surface characteristics of nonstructural materials. Results show that the influences of surface characteristics on the couple vibration frequency of bioliquid-filled microtubule with initial axial stress is larger than that of long-range forces among atoms when the density of bioliquid is larger the density of microtubule, the influences of initial stress on the kth order vibration frequency of individual microtubule gradually become stables when the surface modulus is larger than a given value, and the influence of surrounding cytosol on the transverse vibration of an individual microtubule immersed cytosol increases as axially compressed loading exerted on the individual microtubule increases.     

考虑界面声散射的室内声脉冲响应计算机仿真新算法

本文提出一种考虑界面声散射的室内声脉冲响应的计算机仿真新算法，该算法通过应用动态堆栈和虚拟内存，解决了模拟了中计算可能失运控制的问题，作为例子，文中对二个矩形房间的声脉冲响应进行了仿真。