本研究探討在五種不同外加電場、四種不同種類電解液、三種不同電解液濃度、六種不同pH值及三種不同流道尺寸等參數變化下對電滲流及焦耳熱效應之影響。本實驗使用微質點影像測速儀（MPIV）及雷射誘發微螢光（µLIF）技術進行流場及熱場之量測。研究結果顯示，焦耳熱效應改變原有的電滲流場特性，且對微流體傳輸產生重大之影響，如延散效應。本研究廣泛的探討各個參數對電滲流之影響，利用µLIF所量測到的溫度，對原始的電滲速度數據做溫度之修正，得到一線性的電滲移動率，並將此分析結果與先前文獻做一比較。更進一步分析則塔電位與pH值之關係，且界定出當pH > 7.5時，渠道表面矽醇基的解離會達到飽和狀態。

Experiments were conducted on the investigation of the electroosmotic flow with five different electric field strength, four kinds of buffer solution concentration, six different pH values, and three kinds of microchannel geometry. Joule heating effects were also taken into consideration. Experiments were performed using a microparticle image velocimetry (MPIV) for full field velocity distributions and micro laser-induced fluorescent (μLIF) for full field temperature distributions. It is found that the presence of Joule heating and flow area change could have a great impact on the microfluidic transportation, e.g. dispersion. Furthermore, data were presented and the relation between zeta potential and pH value were discussed in detail. It is found that, as pH > 7.5, all silanol sites are deprotonated.

頁次
目錄.............................................................................................................. i
表目錄........................................................................................................ iv
圖目錄......................................................................................................... v
符號說明................................................................................................... vii
中文摘要.................................................................................................... ix
英文摘要..................................................................................................... x


第一章 序論........................................................................................... 1
1-1 前言............................................................................................ 1
1-2 微流體系統................................................................................ 2
1-3 電雙層的形成............................................................................ 3
1-4 電動現象…................................................................................ 5
1-5 焦耳熱效應................................................................................ 6
1-6 研究背景與目的........................................................................ 7
1-7 文獻回顧.................................................................................... 8

第二章 實驗系統與設備..................................................................... 16
2-1 Micro-PIV及μLIF系統........................................................... 16
2-2 製程設備.................................................................................. 17
2-3 實驗相關設備.......................................................................... 19

第三章 實驗方法及步驟..................................................................... 31
3-1 微渠道製程.............................................................................. 31
3-2 實驗溶液配製.......................................................................... 33
3-3 MPIV/μLIF量測系統建立及原理.......................................... 34
3-4 實驗參數及範圍...................................................................... 36

第四章 理論分析................................................................................. 46
4-1 電泳之理論公式...................................................................... 46
4-2 電滲之理論公式...................................................................... 47
4-3 則塔電位.................................................................................. 49
4-4 速度分析方法.......................................................................... 49
4-5 速度修正方法.......................................................................... 50

第五章 誤差分析................................................................................. 52

第六章 結果與討論............................................................................. 56
6-1 電滲流之流場量測.................................................................. 56
6-2 焦耳熱效應之熱場量測.......................................................... 57
6-3 電滲速度修正及則塔電位分析.............................................. 58

第七章 結論與建議............................................................................. 74
7-1 結論.......................................................................................... 74
7-2 建議與改進.............................................................................. 74

參考文獻................................................................................................... 76
附錄A........................................................................................................ 82

表 目 錄
頁次
表2-1 MPIV及μLIF雷射主要規格.................................................... 21
表2-2 80C77 Hisense CCD camera 詳細規格................................... 22
表3-1 電解液之處方............................................................................ 37
表3-2 MPIV/μLIF量測參數和條件.................................................... 38
表3-3 實驗量測參數及範圍................................................................ 39
表3-4 工作流體之相關性質表............................................................ 40
表5-1 誤差分析表................................................................................ 55

圖 目 錄
頁次
圖1-1 壓力驅動與電動驅動之速度曲線分布示意圖........................ 11
圖1-2 形成電雙層之基礎機制............................................................ 12
圖1-3 電雙層離子及電位分佈示意圖................................................ 13
圖1-4 電滲流動機制示意圖................................................................ 14
圖1-5 流動電流、流動電位、電黏性效應示意圖................................ 15
圖2-1 MPIV及μLIF雷射本體............................................................ 23
圖2-2 CCD攝影機............................................................................... 23
圖2-3 顯微鏡........................................................................................ 24
圖2-4 處理器........................................................................................ 24
圖2-5 旋轉塗佈機................................................................................ 25
圖2-6 單面對準曝光機........................................................................ 25
圖2-7 超音波震盪機............................................................................ 26
圖2-8 工具顯微鏡................................................................................ 26
圖2-9 表面輪廓儀................................................................................ 27
圖2-10 加熱烤板.................................................................................... 27
圖2-11 抽氣櫃........................................................................................ 28
圖2-12 紫外光臭氧清洗機.................................................................... 28
圖2-13 真空乾燥皿................................................................................ 29
圖2-14 精密熱風烤箱............................................................................ 29
圖2-15 電源供應器................................................................................ 30
圖2-16 精密電子天秤............................................................................ 30
圖3-1 微渠道之製程步驟.................................................................... 41
圖3-2 PDMS表面氧化處理................................................................ 42
圖3-3 MPIV/μLIF系統和測試區示意圖........................................... 43
圖3-4 螢光放射強度與螢光染劑濃度之關係圖................................ 44
圖3-5 螢光放射強度與溫度之關係圖................................................ 44
圖3-6 實驗測試微渠道示意圖............................................................ 45
圖4-1 (a)電滲流於壁邊之速度及電位分佈示意圖(b)流體元素
受力示意圖................................................................................ 51
圖6-1 25mM硼酸緩衝液於進口區域、中間區域、出口區域
之(a)流場觀測(b)流場分佈當外加電場強度為5 kV/m.......... 62
圖6-2 25mM硼酸緩衝液之速度分佈曲線於(a)進口區域(b)中
間區域(c)出口區域................................................................... 63
圖6-3 1× TBE緩衝液於中間區域平均速度與電場強度之關係
圖................................................................................................ 64
圖6-4 (a)25mM硼酸緩衝液在三種不同渠道尺寸下(b)200μm
微渠道在三種不同硼酸緩衝液濃度下外加電壓與電流
之關係圖.................................................................................... 65
圖6-5 外加電場強度25kV/m下於進口區域、中間區域、出
口區域之溫度分佈.................................................................... 66
圖6-6 硼酸緩衝液於中間區域平均溫度與外加電場強度之關
係圖(a)不同緩衝液濃度(b)不同微渠道尺寸........................... 67
圖6-7 修正速度與外加電場強度之關係圖........................................ 68
圖6-8 修正速度與溫度修正法之關係圖............................................ 69
圖6-9 電滲移動率與緩衝液濃度之關係圖........................................ 70
圖6-10 (a)電滲移動率與深寬比之關係圖(b)則塔電位與深寬比
之關係圖.................................................................................... 71
圖6-11 則塔電位與pH值之關係圖...................................................... 72
圖6-12 無因次參數ζ*與pC、深寬比和pH值之關係圖....................... 73

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