确定压力敏感带证据的存储:长期研究
1Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), Beltsville, Maryland, USA.
Journal of forensic sciences
|August 9, 2024
概括
法医科学研究发现,联邦快递支,粘合板支和聚透明板是压力敏感粘合带 (PSA) 的最佳存储材料. 这些基板尽量减少干扰,确保精确分析痕迹证据.
科学领域:
- 法医科学 法医科学 法医科学
- 材料科学 材料科学 材料科学
- 分析化学 分析化学
背景情况:
- 压敏粘合带 (PSA) 是法医调查中的关键痕迹证据.
- 对于PSA磁带的最佳存储材料没有得到充分的研究,这可能会影响证据的完整性.
- 基质干扰可能会使带去除和粘合剂分析复杂化.
研究的目的:
- 为了确定PSA磁带的最佳存储基材,尽量减少分析干扰.
- 评估各种储存材料对PSA带的长期影响.
- 确保PSA磁带证据的法医分析的可靠性.
主要方法:
- 长期研究 (10年) 涉及80个PSA带样本在8个不同的基板上.
- 在多个时间点评估带清除易度.
- 使用富里埃变换红外光谱 (FTIR),热解气色谱-质谱 (PyGC-MS),扫描电子显微镜与能量分散光谱 (SEM-EDS) 和X射线光 (XRF) 分析粘合剂组成.
主要成果:
- 联邦快递的支持是唯一的基板,没有显示带带去除的不良影响.
- 联邦快递背板,粘合剂板背板和聚透明板对粘合剂构成的不利影响最小.
- 这些基板在短期和长期PSA磁带存储方面都被证明是有效的.
结论:
- 在法医科学中,建议用于存储PSA带的FedEx背面,粘合板背面和聚透明板.
- 适当的基板选择对于保持粘合物证据的完整性至关重要.
- 这项研究为优化法医痕迹证据处理协议提供了关键数据.
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