红外差谱技术用于微量混合油漆的比对检验

对交通事故中的漆片检材进行同一物质比对时,某些情况下难以提取到单一的油漆碎片而是两辆车的油漆混合在一起,给物证比对带来困难。红外差谱技术具有辨别混合物中不同成分的功能,因此可应用于交通事故中混合油漆检材的比对检验。本文对一起交通事故的漆片检材,分别用三种方式提取、制样,用红外光谱仪进行分析,借助红外差谱技术对谱图进行处理,排除混合油漆的干扰。处理后得到的谱图与样本的谱图进行比对,结果显示两者主要官能团吸收峰位置、峰型、峰强度基本一致,可出具比对一致的结论。针对混合油漆检材的比对检验,红外差谱技术可提供支持。

Application of IR Differential Spectrum Technology into Testing the Mixed Paint of Micro-quantity

Objective To make certain of the legal responsibility of the involved cars in traffi c accidents,the evidential paint chips from the relevant cars were usually compared with one another to verify whether they are of same source or not.However,it is very diffi cult for many cases to extract source-single paint chips in some circumstances.Commonly,the mixed paint chips were obtained,bringing much more obstruction for detection.Here,the IR(infrared)differential spectrum technology was to introduce for solving such a problem so that the different substances can be distinguished from the mixed paint chips.Methods Three methods of extraction and sample preparation were used into different paint chips from a traffi c accident,with the prepared samples being analyzed by IR spectrameter.The spectrograms were processed by IR differential spectrum technology to eliminate the interference among the substances of mixed paint chips.Results Two functional groups were almost the same of their peaks’position,shape and absorption strength between the processed spectrogram and the controlling sample’s.Thus,a conclusion can be made that the two compared samples are same.Conclusion The IR differential spectrum technology can provide supports for comparison of mixed paint chips.