硝酸银、茚三酮显现纸张上汗潜手印的效果比较

本文通过对遗留在不同纸张,不同时间的汗潜手印,分别用硝酸银和茚三酮溶液进行显现,通过观察和比对,发现硝酸银和茚三酮溶液显现效果存在差异,主要是:硝酸银、茚三酮两种溶液显现效果都很好。硝酸银显现速度快,但显现遗留时间较长的手印效果较差。茚三酮显现速度慢,但显现遗留时间较长的手印效果好。在侦查实践中,刑事技术人员如果了解和关注到这种差异,对汗潜手印显现方法作出恰当选择,可达到事半功倍的效果,提高侦查办案的效率,这是本文研究的初衷。

Comparison between Silver Nitrate Effect and Ninhydrin Effect of Presenting Sweat Latent Fingerprints on Paper

Through presenting the sweat latent fingerprints left on different paper at different time by silver nitrate and ninhydrin, this paper discovers some differences between the two kinds of liquor with regard to their effects. Generally, both silver nitrate and ninhydrin are able to present the fingerprints clearly. Taken individually, silver nitrate can present the fingerprints rapidly but is not good at presenting the fingerprints left for a long time; on the contrary, ninhydrin is not so fast to present fingerprints but is good at presenting fingerprints left for long. In investigation practice, if the criminal technicians can pay due attention to these differences and make right choice of fingerprints presenting methods, they can yield twice the result with half the effort and improve the investigation efficiency, which are the research objectives of this paper.