銀奈米物理顯影劑製備與在多孔及非多孔性表面潛伏指紋顯現之應用

Preparation of nano-silver physical developer and its application in developing latent fingerprints on porous and non-porous surfaces

賈中豪(Jung-Hau Jar)

指導教授 ： 張幼珍

元智大學/工程學院/化學工程與材料科學學系/碩士(2009年)

https://doi.org/10.6838/YZU.2009.00299

摘要

物理顯影劑的研究者常指出，物理顯影劑是一種對於潛伏指紋上的非水溶性成份最靈敏的一種試劑。然而在非多孔性表面的顯影與延長物理顯影劑顯影時間的實證研究仍相當缺乏，傳統物理顯影劑配製的程序相當複雜，而且並沒有研究探討物理顯影劑能顯影浸在水中多久的潛伏指紋樣品，因此本研究旨在探討如何簡化物理顯影劑的配製程序，使用新式物理顯影劑在非多孔與多孔性表面上顯影潛伏指紋，以及此新顯影劑能顯影浸在水中多久的潛伏指紋樣品，以期能調製出一個較傳統物理顯影劑有更長使用期限的新式物理顯影劑。
本研究中使用化學還原法來配製奈米銀新式物理顯影劑，並利用場發射電子顯微鏡來觀察顯影劑中銀顆粒的大小。研究結果顯示配製出來的物理顯影劑含有奈米級銀微粒，且將其應用在多孔性及非多孔性表面上均能成功的將潛伏指紋予以顯影。本研究中也利用不同觀察方法來解釋表面材質對顯影的影響。總結，本研究除測試新式物理顯影劑的穩定性，也探討其在多孔性及非多孔性表面上和非新鮮指紋及其在特殊環境下的顯影能力，也嘗試解釋物理顯影劑的機制。

關鍵字

潛伏指紋 ； 奈米銀 ； 物理顯影劑 ； 多孔性表面 ； 非多孔性表面

並列摘要

Researchers of physical developer (PD) have often think about the most sensitive reagent for reacting with water-insoluble components in latent fingerprints. However, research on time needed to develop latent fingerprints on non-porous surface and how to increase shelf-life are still lacking. For traditional PD, there is a complex preparation procedure and no one has discussed the time needed for developing a latent fingerprint on wet items. Therefore, the aims of this research are to explore how to simplify the synthesis procedure, to apply a nano-silver-based PD to develop latent fingerprints on non-porous and porous surfaces, to determine the time needed for the new PD to develop latent fingerprint on wet items, and to extend the shelf-life of new PD.
For the preparation of the nano-silver PD, the chemical reduction method was used. FESM was used to examine and confirm the size range of the silver particles. In addition, microscopy examination was made to explain how well silver nanoparticles adhere to different substrates. The result of this study showed the new PD is a stable suspension of nano-silver particles. Application of the new PD to develop latent fingerprints on both porous and non-porous surfaces was successful. To conclude, this study is of importance in testing the stability of a new PD and its ability to develop fresh and non-fresh latent fingerprint on both porous and non-porous surfaces in normal and special environment. A reaction mechanisms of the new PD was also proposed.

並列關鍵字

latent fingerprint ； nano-silver ； physical developer ； porous surface ； non-porous surface

參考文獻

51.侯鎮球，高中職奈米材料課程實驗之設計－利用化學與電化學還原法制備奈米銀粒子，中正大學，2006年7月。

5.Burow, D., Seifert D. and Cantu A.A., Modifications to the silver physical developer. J. Forensic Sci, 48, 5, 1094-1000(2003).

6.Luo, Y.P. and Wang, Y., A new silver physical developer. J.Forensic Ident, 54, 4, 422-427(2004).

15.Faulds, H., On the Skin Furrows of the Hand. Nature, 22, 605(1880).

16.Herschel, W.J., Skin Furrows of the Hand. Nature, 23, 76 (1881).