2009-08-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/672228摘要：本研究主要探討多孔性球體粒子暨聚電解質在微奈米流體通道的電動力學現象。為了清楚描述多孔粒子在通道中的運動情形，我們突破幾何系統的座標限制，採取球座標與圓柱座標描述此物理系統，且針對粒子任意電荷密度、電解質任意濃度以及管壁因材料特性而帶電情況做研究，並利用Chebyshev多項式為基底的正交配位法進行六區聯解以求系統之穩態解。 　　研究結果發現，多孔膠體粒子所帶電荷量對其泳動度有顯著的效應，且當電荷量大時，因離子雲扭曲產生的極化效應會使電泳動度有一極值產生。而在粒子特性方面，多孔球也因高分子結構所帶電荷密度及摩擦係數大小而影響電泳運動。另一方面，當電解質溶液濃度高即電雙層厚度較厚時，因受限於通道邊界，此時電雙層會受到擠壓而變形，且多孔粒子泳動速度也因邊界效應而變慢；反之電解質溶液濃度低即電雙層較薄時，邊界存在對粒子泳動較不具影響力。且不論電雙層厚度大小，在通道半徑大小夠大時則可忽略邊界效應。此外，管壁帶電與否將劇烈改變電泳的運動行為，因此做電泳分析時也必須注意材料的選擇，錯誤的背景預估將會造成相當大的誤差；相反的則有助於實驗特性分析! <br> Abstract: In this study, electrophoresis of a polyelectrolyte, modeled as a charged porous sphere, in a cylindrical pore is investigated theoretically. Polyelectrolyte is a macromolecule containing a number of dissociable functional groups. Many biologically important macromolecules belong to this category, such as proteins, polysaccharides, DNA, and so on. The governing general electrokinetic equations are then solved with a pseudo-spectral method based on Chebyshev polynomials. We found, among other things, that the polarization effect due to the convection flow within the porous sphere is a crucial factor in determining its electrophoretic behavior. The friction coefficient of the porous particle retards particle mobility greatly as it increases. The presence of a cylindrical pore retards the particle motion in general, as compared with an isolated particle. The boundary effect in terms of the reduction of particle mobility is very significant when double layer surrounding the particle is thick, and diminishes as it gets very thin. With the generation of an electroosmotic flow, the charged wall can either enhance the particle motion or deter it, depending on the double layer thickness. The thinner the double layer, the more significant the influence of the osmotic flow on the particle motion in general. When both the particle and the cylindrical pore are lowly charged, the particle motion can be considered as a simple addition of a charged particle in an uncharged pore and an uncharged particle in a charged pore. The results of this study have potential applications in various microfluidic and nanofluidic operations, such as biosensors and lab-on-a-chip devices.微奈米通道邊界效應多孔膠體粒子聚電解質NanochannelElectrokinetic BehaviorsBoundary EffectPorous Colloid