近年來交流電滲(ACEO)被廣泛使用在微流體的傳輸、混合或微粒子收集上。交流電滲幫浦為在一非對稱指叉型電極上施予交流電訊號，藉由非對稱幾何形狀之電極產生非對稱渦漩，進而造成推動流體的效果。偏壓極化交流電滲(B-P ACEO)為在一對稱式指叉型電極上施予交流電訊號並疊加直流偏壓，藉由非對稱式極化流體產生推動流體的效果。本研究經由實驗結果顯示，偏壓極化交流電滲比交流電滲更能有效推動流體。因此本研究設計對稱式電極與非對稱式電極，探討幾何差異對偏壓極化交流電滲之影響，定義微粒子流經電極表面之速度為表面流速(Vs)，並探討相同電壓、溶液導電度為0.00024S/m之下，頻率對偏壓極化交流電滲之表面流速(Vs)的影響，實驗結果顯示偏壓極化交流電滲與交流電滲皆有一最佳頻率；而在相同電壓下，偏壓極化交流電滲以非對稱式電極Type II有最大之表面流速(Vs)。

Recently AC Electroosmosis (ACEO) has been applied for fluid transport, mixing and micro/nano particles concentrating. ACEO pumping effects happen when ac signals are applied to arrays of asymmetric interdigitated microelectrodes. Net fluid flow is induced by asymmetric fluid vortices which are caused by asymmetric electrode geometries. Biased Polarization AC Electroosmosis (B-P ACEO) is another type of ACEO. Instead of ac sinusoidal signal, dc-biased ac signals are used in B-P ACEO. Based on the electrodes with positive or negative biasd ac signals, Faradic charge and capacitive charging mechanisms occurs. Net fluid flow is formed by different biased polarizations. This thesis reports that pumping effect by B-P ACEO is more efficient than conventional ACEO with the same electrode geometry. This thesis also studies the difference between symmetric electrode and asymmetric electrode of B-P ACEO by difining surface velocity (Vs) which is particle’s velocity along the surface of electrodes. The dependence of surface velocity (Vs) and frequency is descried for the same signal and fluid with conductivity at 0.00024 S/m. Experiments present that there are characteristic frequency on both B-P ACEO and ACEO. Finally, this paper presents that asymmetric electrode Type II of B-P ACEO has the highest surface velocity (Vs) for all driven signals.

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