液固旋流器分离效率的研究

对分离效率与液相流速、油水比例和旋流器级数之间的关系进行了系统的实验研究. 通过受力分 析从理论上对细颗粒易受参数影响的原因进行了阐述，并根据量纲分析和实验数据得到了分 离效率与$Re$数和$St$数之间的函数关系. 在此基础上，对液固旋流器的现 场应用提出了有价值的建议.     

6连通图中的可收缩边

Kriesell(2001年)猜想：如果κ连通图中任意两个相邻顶点的度的和至少是2[5κ/4]-1则图中有κ-可收缩边．本文证明每一个收缩临界6连通图中有两个相邻的度为6的顶点，由此推出该猜想对κ=6成立。     

A novel immunoassay system and bioseparation process based on thermal phase separating polymers

Poly-N-isopropylacrylamide (polyNIPAAm), a water-soluble, thermally precipitating synthetic polymer, has been conjugated together with a monoclonal antibody (MAb) and utilized in a novel separation method for an immunoassay. The PolyMPAAm precipitates out of water above a critical temperature of 31°C, enabling a polymerbound immune complex to be separated from the solution. The principal advantages of this method are that it utilizes a homogeneous incubation for the antigen-antibody reaction, plus, it has the ability to assay large-molecular-weight antigens with sensitivities equivalent to other nonisotopic heterogeneous immunoassays. In addition, since the polymer-immune complex may be reversibly redissolved by cooling, the method may be used both to concentrate the signal and isolate the analyte. This general technique may also be used for a wide variety of separation processes in addition to immunoassays, in which a specific component in a biological fluid, industrial process stream, or body of water is to be isolated for analysis, recovery, or disposal. Thus, product recovery and/or toxin or pollutant removal processes are possible with this methodology.     

Package deal theorems and splitting orders in dimension 1

Let be a module-finite algebra over a commutative noetherian ring of Krull dimension 1. We determine when a collection of finitely generated modules over the localizations , at maximal ideals of , is the family of all localizations of a finitely generated -module . When is semilocal we also determine which finitely generated modules over the -adic completion of are completions of finitely generated -modules.

If is an -order in a semisimple artinian ring, but not contained in a maximal such order, several of the basic tools of integral representation theory behave differently than in the classical situation. The theme of this paper is to develop ways of dealing with this, as in the case of localizations and completions mentioned above. In addition, we introduce a type of order called a ``splitting order' of that can replace maximal orders in many situations in which maximal orders do not exist.

     

The topology of surface mediatrices

Given a pair of distinct points p and q in a metric space with distance d, the mediatrix is the set of points x such that d(x,p)=d(x,q). In this paper, we examine the topological structure of mediatrices in connected, compact, closed 2-manifolds whose distance function is inherited from a Riemannian metric. We determine that such mediatrices are, up to homeomorphism, finite, closed simplicial 1-complexes with an even number of incipient edges emanating from each vertex. Using this and results from [J.J.P. Veerman, J. Bernhard, Minimally separating sets, mediatrices and Brillouin spaces, Topology Appl., in press], we give the classification up to homeomorphism of mediatrices on genus 1 tori (and on projective planes) and outline a method which may possibly be used to classify mediatrices on higher-genus surfaces.     

小波分频在重力异常界面反演计算过程中的应用

重力资料是研究地质结构的重要资料，通常测得的重力异常数据是地下各界面造成的异常的失加，如何把这种叠加效应剥离出来一直是一个难以解决的问题，如果能从综合信息中离出能反映各界面信息的重力异常值，我们就能将问题归结为单界面重力异常的反演问题（关于单界面重力异常的反演可参见文献[1]），小波分析提供了这类问题的新思路。     

Extending the bounds of ‘steady’ RANS closures: Toward an instability-sensitive Reynolds stress model

The incapability of the conventional Unsteady RANS (Reynolds–Averaged Navier Stokes) models to adequately capture turbulence unsteadiness presents the prime motivation of the present work, which focuses on formulating an instability-sensitive, eddy-resolving turbulence model on the Second-Moment Closure level. The model scheme adopted, functioning as a ‘sub-scale’ model in the Unsteady RANS framework, represents a differential near-wall Reynolds stress model formulated in conjunction with the scale-supplying equation governing the homogeneous part of the inverse turbulent time scale ω_h (ω_h = ɛ_h/k). The latter equation was straightforwardly obtained from the model equation describing the dynamics of the homogeneous part of the total viscous dissipation rate ɛ, defined as ɛ_h = ɛ − 0.5ν∂²k/(∂x_j∂x_j) (Jakirlic and Hanjalic, 2002), by applying the derivation rules to the expression for ω_h. The model capability to account for vortex length and time scales variability was enabled through an additional term in the corresponding length-scale determining equation, providing a selective enhancement of its production, pertinent particularly to the highly unsteady separated shear layer region, modeled in terms of the von Karman length scale (comprising the second derivative of the velocity field) in line with the SAS (Scale-Adaptive Simulation) proposal (Menter and Egorov, 2010). The present model formulation, termed as SRANS model (Sensitized RANS), does not comprise any parameter depending explicitly on grid spacing. The predictive capabilities of the newly proposed length-scale determining model equation, solved in conjunction with Jakirlic and Hanjalic’s (2002) Reynolds stress model equation, are presently demonstrated by computing the flow configurations of increasing complexity featured by boundary layer separation from sharp-edged and continuous curved surfaces: backward-facing step flow, flow over a wall-mounted fence, flow over smoothly contoured periodically arranged hills and flow in a 3-D diffuser. The model performances are also assessed in capturing the natural decay of the homogeneous isotropic turbulence and the near-wall Reynolds stress anisotropy in a plane channel. In most cases considered the fluctuating velocity field was obtained starting from steady RANS results.     

A comparison of two no-arbitrage conditions

We give a comparison of two no-arbitrage conditions for the fundamental theorem of asset pricing. The first condition is named as the no free lunch with vanishing risk condition and the second the no good deal condition. We aim to derive a relationship between these two conditions.     

Z-连续偏序集的刻画

在Z-完备偏序集中引入Z-Scott开滤子,并用Z-Scott开滤子的分离性、强分离性刻画Z-连续偏序集,得到Z-连续偏序集的二个刻画定理。     

脊状表面减阻机理研究

针对脊状表面流场的特点,通过实验测量和数值模拟的方法对脊状表面微观流场进行了深入研究,获得了脊状表面湍流边界层的时均速度分布曲线、湍流度分布曲线和微观流场结构.为了得到脊状结构对壁面物性的影响,对脊状表面进行了疏水性测试,获得了液滴在脊状表面上的表观接触角,并通过水洞试验验证了脊状表面的减阻效果.研究表明,与光滑表面相比,脊状表面微观流场结构中存在"二次涡",近壁区的黏性底层厚度比平板的要厚得多,湍流度显著降低,且脊状表面表现出明显的疏水性.由此提出了基于壁面隔离效应、增大湍流阻尼效应和改变壁面物性效应的减阻机理.