基礎講座 電気泳動(Electrophoresis)

The development of novel materials is a fundamental focal point of chemical research; and this interest is mandated by advancements in all areas of industry and technology. A good example of the synergism between scientific discovery and technological development is the electronics industry, where discoveries of new semiconducting materials resulted in the evolution from vacuum tubes to diodes and transistors, and eventually to miniature chips. The progression of this technology led to the development * To whom correspondence should be addressed. B.L.C.: (504) 2801385 (phone); (504) 280-3185 (fax); bcushing@uno.edu (e-mail). C.J.O.: (504)280-6846(phone);(504)280-3185(fax);coconnor@uno.edu (e-mail). 3893 Chem. Rev. 2004, 104, 3893−3946

http://depa.fquim.unam.mx/amyd//archivero/FidelmarLechugaSanabria_4940.pdf

Recent advances in the liquid-phase syntheses of inorganic nanoparticles.

1: Magnetic Particles: Preparation, Properties and Applications: M. Ozaki. 2: Maghemite (gamma-Fe2O3): A Versatile Magnetic Colloidal Material C.J. Serna, M.P. Morales. 3: Dynamics of Adsorption and Oxidation of Organic Molecules on Illuminated Titanium Dioxide Particles Immersed in Water M.A. Blesa, R.J. Candal, S.A. Bilmes. 4: Colloidal Aggregation in Two-Dimensions A. Moncho-Jorda, F. Martinez-Lopez, M.A. Cabrerizo-Vilchez, R. Hidalgo Alvarez, M. Quesada-PMerez. 5: Kinetics of Particle and Protein Adsorption Z. Adamczyk.

Surface and Colloid Science

This chapter introduces the finite element method (FEM) as a tool for solution of classical electromagnetic problems. Although we discuss the main points in the application of the finite element method to electromagnetic design, including formulation and implementation, those who seek deeper understanding of the finite element method should consult some of the works listed in the bibliography section.

Introduction to the Finite Element Method

Applied Numerical Analysis. By C.F. Gerald. Pp. xii, 340. £3·60. 1970. (Addison-Wesley.)

The electrophoretic behavior of a nonrigid entity, e.g., liquid entity or bubble, in a spherical cavity is analyzed theoretically taking the effect of double-layer polarization into account. We show that the electrophoretic mobility of the entity decreases as the ratio (viscosity of surrounding fluid/viscosity of medium inside entity) decreases and its surface potential decreases. If the surface potential is sufficiently high, double layer polarization has the effect of producing a local minimum in the electrophoretic mobility as double layer thickness varies. If the double layer is thick, depending upon the level of surface potential, the limiting electrophoretic mobility when the viscosity ratio is much larger than unity (e.g., gas bubble in liquid) is about 5−10 times of that when the viscosity ratio is much smaller than unity (e.g., rigid particle in liquid). For a thin or medium-thick double layer, the limiting electrophoretic mobility when the viscosity ratio is much larger than unity is about 3 tim...

Electrophoresis of a Nonrigid Entity in a Spherical Cavity

This study examined shape changes in two typical wastewater flocs subjected to cyclic freezing and thawing and the associated force exerted by the ice front. While freezing, the engulfing ice front gradually pulled the floc apart. Subsequent thawing only partially restored the floc's shape. By the Maxwell model, used to interpret gross shape deformations, both flocs were visco-elastic objects exhibiting time-varying rheological characteristics which were more viscous than elastic. Detailed observations of floc 1 deformation demonstrated a two-stage force–displacement relationship. Following 1 cycle of freezing and thawing, the interior structure of the floc deteriorated and the force required to elongating a unit length of floc decreased by 60%. The original floc 2 had a dense “core” and loose “tail”; the core was more resistant to deformation under normal stress than the loose tail. Although both flocs had similar shapes and sizes and were acquired from the same activated sludge stream at a wastewater treatment plant, their rheological behaviors differed substantially. A comprehensive theoretical model for freezing and thawing processes should incorporate these rheological characteristics as they corresponded to observed structural changes and reduction in bound water content in sludge following a cyclic treatment of freezing and thawing.

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Micromechanics of wastewater sludge floc: force-deformation relationship at cyclic freezing and thawing.

The presence of a boundary on the diffusiophoretic behavior of a particle is analyzed by considering the diffusiophoresis of a charged, finite cylindrical particle along the axis of an uncharged cylindrical pore filled with an electrolyte solution. Compared with the other similar geometries considered in the literature, the boundary effect is the most significant in the present geometry, thereby highlighting its importance. The influence of chemiphoresis arising from two types of double-layer polarization (DLP) and that of the electrophoresis effect coming from the difference in the ionic diffusivities on the diffusiophoretic behavior of a particle are discussed. We show that this behavior can be influenced both quantitatively and qualitatively by the boundary. This is because all of the relevant factors, including the DLP effect, the electrophoresis effect, the electric repulsive force between the particle and the co-ions outside its double layer, and the hydrodynamic drag all depend highly on the degree...

Importance of Boundary Effect on the Diffusiophoretic Behavior of a Charged Particle in an Electrolyte Medium

The soft baking step of a photolithography process is analyzed theoretically, taking the effect of the temperature dependence of the diffusivity of solvent into account. A coordinates-transform technique is chosen to solve the moving boundary problem under consideration. The temporal variation of the thickness of a film is predicted, and the result obtained justified by fitting experimental data reported in the literature for both poly(methylmethacrylate) film and Shipley UVIII photoresist. We show that, depending upon the types of photoresist film and the operating conditions, the transport of solvent may be controlled by the diffusion of solvent in a film or the convective transport of solvent from the gas–film interface to the bulk gas phase.

Mathematical analysis of soft baking in photolithography

Electrophoresis is one of the most important analytical tools for the quantification of charged entities in a dispersing medium. Although the electrophoresis of rigid entities has been studied exte...

Jyh-Ping Hsu

Papers

Electrophoresis of a Nonrigid Entity in a Spherical Cavity

Micromechanics of wastewater sludge floc: force-deformation relationship at cyclic freezing and thawing.

Importance of Boundary Effect on the Diffusiophoretic Behavior of a Charged Particle in an Electrolyte Medium

Mathematical analysis of soft baking in photolithography

Electrophoresis of a Concentrated Dispersion of Nonrigid Particles