使用ATR-FTIR光谱学进行密封的特征和差异化的快速和非破坏性方法
Dimple Bhatia1, Chongtham Nimi1, Sweety Sharma2
1Department of Forensic Science, Punjabi University, Patiala, India.
Journal of forensic sciences
|August 22, 2023
概括
验证文件的真实性依赖于密封的完整性. 减弱总反射度-里埃变换红外 (ATR-FTIR) 光谱与化学测量准确区分密封品牌,帮助法医调查.
科学领域:
- 法医科学 法医科学 法医科学
- 分析化学 分析化学
- 频谱学是一种光谱学.
背景情况:
- 密封对于文档真实性和证据完整性至关重要.
- 对印章的改损害了证据的可靠性.
- 密封材料的化学和物理分析对于验证至关重要.
研究的目的:
- 通过ATR-FTIR光谱和化学测量,从12个印度品牌中区分密封样本.
- 建立一种可靠的方法来识别密封的来源.
- 通过将被质疑的样品联系起来,以支持法医调查.
主要方法:
- 来自12个品牌的样品被化,冷却,并通过ATR-FTIR光谱学 (4000-600厘米-1) 分析.
- 使用主要组件分析 (PCA) 和PCA-线性区分分析 (PCA-LDA) 分析了Spectra.
- 经过PCA-LDA模型的训练和验证,以确保分类准确性.
主要成果:
- 该PCA-LDA模型在培训中达到95.83%的准确性,在验证中达到83.33%的准确性.
- 对各种基板 (布料,纸板,纸张) 上的样品实现了100%的准确分类.
- 一项盲目的研究成功地将五个未知样本分为各自的组.
结论:
- 与PCA-LDA相结合的ATR-FTIR光谱法是密封认证的有效方法.
- 这种技术通过识别密封的来源,提供了宝贵的调查线索.
- 该方法增强了对文件和证据的完整性评估.
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