In the field of forensic science, detecting gunshot residue (GSR) particles on an individual or his belongings can connect him to a firearm discharge. One of the most important aspects in research into primer discharge residue analysis is the mechanism of residue particle formation. Understanding the particle formation mechanism should help the forensic scientist to differentiate GSR from particles originating from other sources. The elemental composition of GSR particles depends upon the type of ammunition used. Modern Western ammunition all contain a very similar priming composition, the basic elements found being Lead (Pb), Barium (Ba) and Antimony (Sb). However, some manufacturers add Aluminum (Al) to the primer mixture, this addition may result in GSR particles composition of PbBaSbAl. Our experience in analyzing GSR particles derived from ammunition containing Al suggests that the addition of Al to the primer often causes elements separation forming particles with regions of distinct composition instead of one homogenous particle type. One particle-region-type predominantly includes the elements Pb and Sb, with a small amount of Ba, and the other particle-region-type predominantly contains Al and Ba. We replicated and explained this phenomenon using information theory analysis as well as running a molecular dynamic simulation, both on large-scale systems.

在法医学领域，检测个人或其随身物品上的枪弹残留 (GSR) 颗粒可以将他与枪支发射联系起来。底漆排放残留分析研究中最重要的方面之一是残留颗粒形成的机制。了解粒子形成机制应该有助于法医科学家将 GSR 与来自其他来源的粒子区分开来。GSR 粒子的元素组成取决于所用弹药的类型。现代西方弹药都包含非常相似的引爆成分，发现的基本元素是铅 (Pb)、钡 (Ba) 和锑 (Sb)。然而，一些制造商将铝 (Al) 添加到底漆混合物中，这种添加可能会导致 GSR 颗粒成分为 PbBaSbAl。我们分析源自含铝弹药的 GSR 颗粒的经验表明，向底漆中添加铝通常会导致元素分离，形成具有不同成分区域的颗粒，而不是一种均质颗粒类型。一种颗粒区域类型主要包括元素Pb和Sb，并含有少量Ba，另一种颗粒区域类型主要包含Al和Ba。我们使用信息论分析以及在大型系统上运行分子动力学模拟来复制和解释这种现象。含有少量 Ba，另一种颗粒区域类型主要含有 Al 和 Ba。我们使用信息论分析以及在大型系统上运行分子动力学模拟来复制和解释这种现象。含有少量 Ba，另一种颗粒区域类型主要含有 Al 和 Ba。我们使用信息论分析以及在大型系统上运行分子动力学模拟来复制和解释这种现象。