Experimental investigation of turbulent natural convection flow in a channel

This paper presents the results of velocity measurements of natural convection in symmetrically heated vertical channel using the particle image velocimetry (PIV) system. Velocity measurements were conducted at three different sections on the horizontal plane to validate the flow two-dimensionality and at three different heights in the vertical plane to establish vertical mean velocity profiles. The results indicate a considerable influence of the Rayleigh number and aspect ratio on the mean velocity profile. The results also indicate significant diffusion rates of the vertical mean velocity component and normal Reynolds stresses towards the center of the channel.     

Vertical integration with endogenous contract leadership: Stability and fair profit allocation

This paper studies vertical integration in serial supply chains with a wholesale price contract. We consider a business environment where the contracting leader may be endogenously changed before and after forming the integration. A cooperative game is formulated to normatively analyze the stable and fair profit allocations under the grand coalition in such an environment. Our main result demonstrates that vertical integration is stable when all members are pessimistic in the sense that they are sure that they will not become the contracting leader if they deviate from the grand coalition. We find that in this case, the grand coalition’s profit must be allocated more to the retailer and the members with higher costs. Nevertheless, we also show the conditions under which the upstream manufacturer can have strong power as in traditional supply chains.     

Antibiotic Detection in Urine Using Electrochemical Sensors Based on Vertically Aligned Carbon Nanotubes

A sensitive way to determine levofloxacin using a sensor based on vertical aligned carbon nanotubes is described. The morphology and the electrochemical performance of the electrodes were characterised by atomic force microscopy, cyclic voltammetry and square wave voltammetry. A scan‐rate study and electrochemical impedance spectroscopy showed that the levofloxacin oxidation product is adsorbed on the electrode surface. Differential pulse voltammetry in phosphate‐buffer solution allowed the development of a method to determine levofloxacin levels in the range of 1.0–10.0 µmol L^?1, with a detection limit of 75.2 nmol L^?1. The proposed sensor was successfully applied in the determination of levofloxacin in urine, and the obtained results were in full agreement with those from the HPLC procedure.     

The study of laser self-mixing vibrometer employing different feedback regime using a VCSELS

Laser interferometry based on self-mixing effect widely used to measure displacement, velocity, vibration and distance due to compactness, non-contact, as well as low cost. An important use of the self-mixing effect inside a laser diode is in optical self-mixing vibrometer. We have experimentally investigated self-mixing interference produced by the feedback of light from a vibrated target into a vertical-cavity surface-emitting laser for sensing applications. In this paper, the self-mixing vibrometer employing different feedback regime is discussed and a theoretical analysis is also proposed. Numerical analysis focused on the distortion self-mixing waveform. Numerical analysis and experimental results show that mode-hop occurs when the laser self-mixing vibrometer employing at high feedback level.     

Prediction of the evolution of the dispersed phase in bubbly flow problems

For modeling multi-phase where the dispersed phase plays a major role in determining the flow structure and inter phase transfer quantities, the size distribution of the bubbles has to be considered. This can be done by extension of the mass balance equation to a population balance equation. In this work, a least squares spectral method is tested for predicting the evolution of the dispersed phase in a vertical two-phase bubbly flow. The least squares spectral method consists in minimizing the L² norm of the residual over the simulation domain. The results are compared with experimental data obtained for two different initial bubble distributions.     

基态Se2x（x=0,-1，+1,+2）分子离子的势能函数与垂直电离势

用原子分子反应静力学原理推导出了Se2x(x=0,+1,-1,+2)分子离子的基态电子状态及其离解极限.在6-311G**水平基础上,用B3LYP方法计算了Se2x(x=0,-1,+1,+2)分子离子的基态电子状态的平衡几何Re和离解能De及谐振频率;并在计算出来的一系列单点能基础上,用正规方程组拟合Murrell-Sorbie(M-S)势能函数,得到相应态的解析势能函数,由此计算对应的光谱参数和力学性质;计算了Se2+、Se22+的垂直电离势;计算表明Se2x(x=0,+1,-1,+2)分子离子是可稳定存在的.     

Vertical and oblique fault detection in explicit surfaces

The purpose of this paper is to study the problem of detection of vertical and oblique faults in explicit surfaces. First, we characterize the finite jump discontinuities of a univariate function in terms of the divergence of sequences related to the slopes of least-squares polynomial approximations of the function. Then, we propose an algorithm to locate the finite jump discontinuities of a univariate function and its first derivative from a finite set of scattered data values of the function. As a consequence, we derive a method to detect vertical and oblique faults in explicit surfaces when the data sets are distributed along lines. We finally present some numerical and graphical examples.     

Advancements of vertically aligned liquid crystal displays

This review describes the recent advancements in the field of the vertical aligned (VA) liquid crystal displays. The process and formation of different vertical alignment modes such as conventional VA, patterned VA, multi-domain VA, and polymer stabilised VA etc are widely discussed. Vertical alignment of liquid crystal due to nano particle dispersion in LC host, bifunctional PR-SAM formed by silane coupling reaction to oxide surfaces, azo dye etc., are also highlighted and discussed. Overall, the article highlights the advances in the research of vertical aligned liquid crystal in terms of their scientific and technological aspects.     

Chemical reaction and Soret effects on MHD convective flow of second grade fluid through an absorbent medium with ramped wall temperature as well as ramped surface concentration

In the present paper, the heat generating and/or absorption as well as thermo-diffusion on the unsteady free convection MHD gyrating flow of radiation and chemical reactive second grade fluid past an unbounded perpendicular plate during absorbent medium have been discussed. Here, it is assumed that, the confining plate has the ramped wall temperature with ramped surface concentration and isothermal temperature with ramped surface concentration. The analytical solutions for the governing equations are found by utilization of Laplace transformation methodology. The velocity, temperature and concentration profiles are analyzed with quite few figures. It is determined that, velocity, temperature and concentration distribution sketches in case of ramped temperature as well as ramped surface concentration are not as much of as those of isothermal temperature as well as ramped surface concentration. In addition to the idioms of skin friction, Nusselt number as well as Sherwood number are achieved and characterized numerically with tabular format.