English  |  正體中文  |  简体中文  |  全文筆數/總筆數 : 64745/64745 (100%)
造訪人次 : 20454251      線上人數 : 305
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
搜尋範圍 查詢小技巧:
  • 您可在西文檢索詞彙前後加上"雙引號",以獲取較精準的檢索結果
  • 若欲以作者姓名搜尋,建議至進階搜尋限定作者欄位,可獲得較完整資料
  • 進階搜尋


    請使用永久網址來引用或連結此文件: http://ir.lib.ncu.edu.tw/handle/987654321/7550


    題名: 銅氧核殼奈米顆粒的雙分量自旋極化;Tow-components spin polarization in Cu/O core-shell nanoparticles
    作者: 李宗儒;Zong-Ru Li
    貢獻者: 物理研究所
    關鍵詞: ;自旋極化;Cu;spin polarization
    日期: 2008-06-20
    上傳時間: 2009-09-22 10:59:48 (UTC+8)
    出版者: 國立中央大學圖書館
    摘要: 本實驗採用熱蒸鍍法製備兩組銅奈米顆粒後至於空氣中分別得到在外圍包覆不同氧化厚度的銅氧核殼奈米粒子,經由X光繞射圖分析我們得到其中四組銅與氧化亞銅的比例為1:1、3:1、3:2、4:21,最後經由X光繞射寬的擬合以及AFM粒徑影像的比對我們定義出樣品的粒徑為7.2、8.8、9、12.4 nm。 經由磁化強度與磁化率的測量得知系統中具有兩個磁分量因此使用兩個朗之萬函數加一線性抗磁項來描述此其磁性,我們推測兩個磁分量分別為銅以及氧化亞銅自旋極化,銅的自旋極化飽和磁化強度隨溫度無明顯變化趨勢,而由氧化亞銅自旋極化的飽和磁化強會隨溫度升高而遞減,兩者的磁矩數皆隨溫度升高而增加,此外比較各組樣品由銅所產生的磁性以及抗磁性質,發現其強度會隨銅粒徑的減少而增強。 Five core shell Cu/Cu2O nanoparticles were fabricated by thermal evaporation method. The outer Cu2O shell was formed by expose the Cu nanoparticle to the air . X-ray difference studies show that the mole ratio of Cu/Cu2O in the four samples are 1:1, 3:1, 3:2, 4:21. The mean particle diameters were determinded from the X-ray peak profiles and the AFM images . The mean diameters are 7.2, 8.8, 9, 12.4 nm. Magnetization and ac magnetic susceptibility measurements were performed to study the magnetic properties. Dual Langevin function plus a linear diamgnetism term were may be used to describe the M-H curves, which represent the contribution from Cu spin polarized, Cu2O spin polarized, and diamgnetism respectively. No obvious change in the saturate magnetization of Cu moment was found, whereas that of Cu2O decreases with increased temperature. The average particle moments of both Cu and Cu2O component were found to increase when temperature is increased. On other hand, the diamgnetism and saturation magnetization of Cu increase as particle diameter is decreased.
    顯示於類別:[物理研究所] 博碩士論文

    文件中的檔案:

    檔案 大小格式瀏覽次數
    0KbUnknown496檢視/開啟


    在NCUIR中所有的資料項目都受到原著作權保護.

    社群 sharing

    ::: Copyright National Central University. | 國立中央大學圖書館版權所有 | 收藏本站 | 設為首頁 | 最佳瀏覽畫面: 1024*768 | 建站日期:8-24-2009 :::
    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - 回饋  - 隱私權政策聲明