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Plasmonic Enhanced Optical Disk Reactor for Wastewater Treatment
No full text 對於生活在21世紀的人類而言，環境保護是文明發展所必須面對的一大課題；而在水資源有限的台灣，水資源的維護與污水處理更是環保議題中不可忽視的部份。本研究中所探討的是以電漿子增益之半導體光觸媒分解水中有機污染物。近代半導體光觸媒之研究約始於1969年，由日本的K. Honda和A. Fujishima兩位教授首先以實驗證明二氧化鈦光觸媒可應用在氫燃料生成的技術。自此之後，許多研究人力與資源投入了光觸媒的研究，也包含了利用光觸媒進行污水處理；其中，氧化鋅光觸媒以高光敏感度、高物理穩定性、低成本與大能隙等優勢，成為最受歡迎的光觸媒材料之一。
光觸媒以光作為啟動化學反應的能量源，而研究人員的終極目標為研發出可直接在地表以太陽光驅動之架構。然而，具應用價值之半導體光觸媒通常擁有高能隙，使之只能吸收紫外光的光子；對於太陽光譜佔了90%以上能量的可見光與進紅外光而言，半導體光觸媒是無法直接運用的。研究人員提出了許多方法，嘗試去改變光觸媒的光學性質，主要分成添加其他物質和在半導體中製作缺陷等兩種方法。本研究主要探討的方法就是添加具侷域表面電漿共振特性之奈米金屬粒子至光觸媒中，以其熱電子效應使整個光觸媒系統可利用可見光進行化學反應，並提升整體反應效率。
本研究開發了一個大面積製作含有奈米金屬粒子之氧化鋅奈米柱，此結構是生長於光碟片基板上，並可結合特殊設計之旋轉反應器進行高效率的污水分解程序。樣品成長過程中，氧化鋅奈米柱的生長是以水熱法達成，水熱法可以相對低的成本與溫度成長徑直的奈米柱，使奈米柱合成過程保持光碟片基板的完整性。光碟片基板雖然不耐熱，但是擁有可高速旋轉的物理結構以及耐衝擊等優勢，非常適合應用於本研究。本研究中使用的奈米金屬粒子為銀粒子，擁有非常強的侷域表面電漿共振。本研究中使用濺鍍法在氧化鋅奈米柱表層形成銀奈米顆粒。氧化鋅奈米柱以及銀奈米粒子的表面形貌由掃描式電子顯微鏡進行觀測。本研究中以甲基橙水溶液模擬污水，而其濃度可由穿透光譜系統進行監控。在樣本參數最佳化的情況下，本系統可在20分鐘內分解溶液中90%以上之甲基橙分子。Environmental protection is one of the most crucial issues of the human civilization in the 21st century. Researchers have been working on using semiconductor photocatalyst for organic chemical decomposition since 1969, the year when Honda-Fujishima effect was experimentally demonstrated. Among the photocatalytic materials, zinc oxide (ZnO) has attracted much attention due to its high photosensitivity, stability, low cost, and wide band gap.
However, the wide band gap of semiconductor photocatalysts results in low absorption in the visible and infrared region. This property limits the possibility of the ultimate goal of photocatalysts: using solar energy for direct chemical reaction, since the over 90% of solar power is carried by photons in visible or infrared region. Researchers have been working on artificial defects and additives to modify optical properties of photocatalyst. The localized surface plasmon resonance, together with its induced hot electron effect, is one of the most promising strategies to solve the enigma.
In this work, a process of growing large-area plasmonic-nano-particles-decorated ZnO nanorods on the polycarbonate optical disk substrate was developed, while a corresponding photocatalytic rotational reactor was fabricated. Hydrothermal process was adapted to grow ZnO nanorods perpendicular to the optical disk substrate at relatively lower temperature. The optical disk substrate has advantages of durable property in fast rotation and high impact-resistance. The plasmonic nano-particles, in this case, silver nano-particles, were deposed on the ZnO nanorods by direct sputtering. The morphology of ZnO nanorods and plasmonic nano-particles was investigated by Scanning Electron Microscope (SEM).
The photocatalytic activity of the sample was evaluated by the degradation of methyl orange (MO) as a model compound in aqueous solution, and the decomposition rate of MO molecules is monitored by the optical spectroscopy measurements. In the optimized condition, less than 10% of the MO remained in the aqueous solution after a 20-minute treatment in the rotational reactor with our sample.口試委員會審定書........................................................................................................... I
序言 .................................................................................................................................. II
中文摘要 ........................................................................................................................ III
英文摘要 ........................................................................................................................ IV
目 錄 ............................................................................................................................ VI
圖目錄 ............................................................................................................................ IX
表目錄 ......................................................................................................................... XVI
第一章 緒論 .............................................................................................................. 1
1.1 前言 .................................................................................................................. 1
1.2 半導體光觸媒簡介 .......................................................................................... 2
1.2.1 原理 .......................................................................................................... 2
1.2.2 常見材料 .................................................................................................. 5
1.2.3 一般污染物分解架構 .............................................................................. 6
1.3 表面電漿共振簡介 .......................................................................................... 8
1.3.1 體積電漿振盪原理 .................................................................................. 8
1.3.2 介面與薄膜表面電漿共振原理 ............................................................ 10
1.3.3 侷域表面電漿共振原理 ........................................................................ 14
1.3.4 表面電漿共振之應用 ............................................................................ 16
VII
1.4 表面電漿共振增益光觸媒簡介 .................................................................... 16
1.4.1 原理 ........................................................................................................ 16
1.4.2 發展歷史 ................................................................................................ 20
1.5 研究目的 ........................................................................................................ 20
第二章 實驗架構 .................................................................................................... 21
2.1 前言 ................................................................................................................ 21
2.2 光碟片旋轉反應系統 .................................................................................... 21
2.2.1 構想與優勢 ............................................................................................ 21
2.2.2 光碟片基板簡介 .................................................................................... 22
2.3 氧化鋅奈米結構製備 .................................................................................... 23
2.3.1 氧化鋅奈米結構的選擇 ........................................................................ 23
2.3.2 氧化鋅奈米柱常見合成方法 ................................................................ 24
2.3.3 半導體表面處理 .................................................................................... 26
2.4 銀奈米粒子製備 ............................................................................................ 27
2.4.1 常見銀奈米粒子製備法 ........................................................................ 27
2.4.2 芝浦 CFS-4EP-LL 濺鍍機簡介 ............................................................. 28
2.5 表面電漿子增益光碟片製作參數與量測 .................................................... 30
2.5.1 水熱法製作氧化鋅奈米柱 .................................................................... 30
2.5.2 氧化鋅表面處理 .................................................................................... 31
2.5.3 濺鍍法製作銀奈米粒子 ........................................................................ 31
2.5.4 汙染物分解效率量測系統 .................................................................... 33
VIII
第三章 實驗結果與分析 ........................................................................................ 38
3.1 前言 ................................................................................................................ 38
3.2 氧化鋅奈米柱樣品分析 ................................................................................ 38
3.3 旋轉反應系統轉速測試 ................................................................................ 39
3.4 乾蝕刻效果探討 ............................................................................................ 43
3.5 銀奈米粒子加工樣本效率分析 .................................................................... 46
3.5.1 銀奈米粒子參數測試 ............................................................................ 46
3.5.2 表面電漿增益光觸媒效率測試 ............................................................ 48
第四章 結論 ............................................................................................................ 53
參考文獻 ........................................................................................................................ 54
附錄 ................................................................................................................................ 6
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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