红外光谱技术在物证鉴定中的应用

物证鉴定过程中，利用仪器分析技术快速准确的检测物证的化学组成会有助于获取更多案件相关的信息，常用的技术手段有色谱、质谱和光谱技术。法庭科学实验室涉及鉴定的物证种类繁多、情形复杂，需要根据物证的种类和仪器特性决定使用何种分析方法。比如气相色谱-质谱联用技术具有高分辨率、高灵敏度、强鉴别能力的优点，常被用于火灾现场易燃液体等物证的检测分析。法庭科学实验室更常见的应用情形是对与案件有关的各种有机物证(墨迹、油漆、塑料等)及无机物(矿物、无机填料等)进行快速有效分析。红外光谱法是鉴定化合物和测定分子结构的最有效的常规分析方法之一，尤其在法庭科学领域物证鉴定中被广泛应用，红外光谱技术可用来确定物证的种类，同时红外光谱又是一种有效的比对检验手段，检验结果可以为法庭断案提供证据。该文综述了红外光谱技术在法庭科学文件检验、油脂检验、塑料检验、油漆检验、纤维检验以及常见毒品等物证检验领域的应用现状及最新的研究进展，并对红外光谱技术在物证鉴定领域的应用前景进行了展望，以期从实际应用的角度为法庭科学研究人员提供红外光谱技术在该领域的研究概貌。

Application of IR in the Field of Evidence Identification

In the process of evidence identification,detecting chemical composition of evidence with instrumental analysis tech-niques will help get more information relevant to the case quickly and accurately,while the commonly used techniques are chro-matography,mass spectrometry and spectroscopy techniques.Forensic science laboratory relates to the identification of evidence from a wide range of complex situations,we need to decide what kind of analytical methods according to the type of physical evi-dence and instrument characteristics.For example,with the advantages of high resolution,high sensitivity,and strong ability to analysis;gas chromatography-mass spectrometry is often used to detect evidence of fire scene such as flammable liquids.The more common scenarios of the application in forensic science laboratory is related to the case of various organic certificate (ink, paint,plastic,etc.)and inorganic (mineral,inorganic fillers,etc.)for quick and efficient analysis.Infrared spectroscopy is one of the most effective conventional analysis methods to identify and determine the molecular structure of the compound,whihc is especially widely used in the field of forensic science evidence identification.The infrared spectroscopy technique can be used to determine the type of evidence,which also serves as an effective means of test;the test results can offer evidence to the court to settle a lawsuit.This paper reviewed the application status and latest research advances of infrared spectroscopy technique in fo-rensic document examination,oil test,plastic test,paint inspection,fiber inspection,common areas of drugs and other evidence examination,and prospected infrared spectroscopy technology in the field of evidence identification,from a practical point of view to provide infrared spectroscopy research profile for the scientific research personnel.