Dynamics of perturbed equilateral and collinear configurations of three point vortices

Using the technique of asymptotic expansions, we calculate trajectories of three point vortices in the vicinity of stable equilateral or collinear configurations. We show that in an appropriate rotating coordinate system each vortex moves in an elliptic orbit. The orbits of the vortices have equal eccentricities. The angle and ratio between the major axes of any two orbits have a simple analytic representation.      

Higher order symmetrizer and application to an unusual transport equation

We study a class of stationary transport equation with nonlocal low-order tems We obtain the existence and uniqueness of a solution in sobolev spaces     

求解复杂湍流的非线性涡黏性系数模型和代数应力模型

非线性涡黏性系数模型和代数应力模型联系了线性涡黏性系数湍流模型和完整的微分 雷诺应力模型.随着它们受到日益关注,其形式也越来越多样化.本篇综述的目的是对这些模 型加以总结并比较它们之间的共同点及不同之处,指出它们与完整微分雷诺应力模型之间的 关系,以及相对于线性涡黏性系数模型而言它们在预报流场上所具有的优势.     

A new approach to studying the dynamics of a thin curved vortex

The paper studies the dynamics of a thin curved vortex in a potential flow of an ideal incompressible fluid. The flow is specified by a number of geometrical restrictions and does not satisfy the Biot–Savart law. The form of the derived equation of the vortex dynamics coincides with the form of the wellknown equation of local induction for selfinduced vortex motion. The parameters of the new equation are simultaneously flow parameters, and in this sense, they do not show uncertainty typical of classical equations. The coefficient of the new equation can take any specified values (not necessarily much greater than unity, as required according to the concept of local induction) and generally is a function of a natural filament parameter.     

Stability of the relative equilibrium of three vortex charges with zero total intensity

The relative motion of three vortex charges with zero total intensity in a rotating baroclinic fluid is considered in the quasi-geostrophic approximation. The geometry and the linear stability of the relative equilibrium positions of the charges are analyzed. The motion parameter values are classified with respect to the number, type, and stability of equilibrium positions.     

Determination of electron affinity of carbonyl radicals by means of negative ion mass spectrometry

Appearance energies of [M-H](-) ions from carbonyl compounds R-CO-R' (R,R' = H, CH(3), NH(2), OH) have been measured by means of negative ion mass spectrometry in resonant electron capture mode. Values of electron affinity of the corresponding radicals, CH(2)&dbond;C(X)O, NH&dbond;C(X)O and O&dbond;C(X)O, have been determined. Copyright 1999 John Wiley & Sons, Ltd.     

The multi-functional aspect of scanning holographic microscopy: a review(Invited Paper)

Recent developments in scanning holographic microscopy that offer the prospects of new quantitative tools and imaging modalities in bio, micro, and nano sciences are reviewed. The versatility of the method is emphasized. Scanning holography can operate in an incoherent mode for fluorescence imaging, in a coherent mode for quantitative phase imaging, or in a tomographic mode for axial sectioning and rejection of the out-of-focus haze. Possible applications are illustrated with examples, and future prospects ...