靜電現象是一種自幾千年前就發現的自然界奇觀，然而，到底靜電如何形成、機制如何，至今仍未完全清楚。雖然如此，在許多科學家竭盡心力地探討這種神奇的現象之後，一些靜電特性背後的物理原因也逐漸被發掘；例如：引發導體的靜電之原因在於其原子能階的高低不同。然而，非導體的狀況就複雜多了，甚至可以說”視狀況而論”，無法有統一的原理可以適用。
因此，本研究主要係探討顆粒床中的靜電現象。本研究中有四個實驗，分別探討下列議題：1.相同材質間是否會產生靜電。2.顆粒床中，邊壁產生靜電較多或底面產生靜電較多，也就是說，邊壁與底面何者決定顆粒床的靜電現象。3.振動條件對飽和電荷如時間常數的影響如何。4.顆粒流的固相比例（Solid fraction）對靜電累積的影響。在本研究中，靜電摩擦序列表及接觸壓差（CPD）的觀念將會用來引導並架構所有實驗的結果。

Electrostatic charge is a common seen phenomenon which had been found and attracted many interest since thousand years ago. However, the detailed mechanism about how it shape and what agent take part in are still an obscure map in this moment. Though, there are many scientists have tried their best to investigate the fascinating phenomenon which had gradually disclosed the physical reason behind the electrostatic characteristics. For instance, the mechanism of electrostatic charge induced from conductors is already comprehended through theory regarding atom energy level. Still, the sophisticated agent regarding insulator is not yet understood, even worse, sometimes the circumstances are case by case without unitary.
Thus, this study is presented to focus the electrostatic phenomenon inside the Vibrating Granular Bed. Four experiments are carried out to survey the electrostatic characteristics: 1. whether static charge arises when identical beads contact each other, 2. does sidewall or bottom wall of contact generate static charge more, that means which area of contact predominates the charge accumulation, 3. the effect of vibrating condition to the time constant and saturated charge, 4. the effect of solid fraction to static charge accumulation. From this study, the concept of electrostatic tribo-series and contact potential difference (CPD) are introduced to construct the basic theorem and essential ground of all experiments.

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