Detecting Gunshot Residue from Sellier & Bellot Nontox Heavy Metal‐free Primer by in situ Cathodoluminescence

Gunshot residue (GSR) from the discharge of ammunition can provide crucial information in reconstructing criminal cases. Traditional primers create particles of heavy metals such as lead, barium, and antimony. In forensic laboratories, automatic inorganic particle detection is performed by scanning electron microscopy (SEM), using the backscattered electron signal to search for bright residues among the many darker environmental particles, due to higher electron density of the former. Some innovative primers, indicated as heavy metal‐free (HMF), produce a residue of elements with atomic numbers below 21, urgently demanding new detecting solutions. For the first time, residues from Sellier & Bellot Nontox HMF primer are demonstrated to emit visible light under electron beam stimulation in a SEM. Cathodoluminescence is then proposed as a promising tool to both detect and characterize residues in forensic cases involving HMF primers, with minor changes to traditional analytical apparatus used for inorganic GSR analysis.     

灾难性危机事件中的心理干预

灾难性危机事件具有巨大的破坏性。它不仅在物质方面造成巨大的经济损失。而且威胁到社会的秩序和民众的生命安全。导致社会的混乱。更为重要的是强烈而显著地影响着人的心理。因此，必须寻找科学、合理的危机心理干预方法。帮助人们学会应对危机．提高自身处理危机的能力，以克服或减少危机所带来的损害。尽早地从危机中恢复过来。[编者按]     

一种利用红外对射光电感烟探测器测量烟气层界面高度的思路

烟气层界面高度是火灾试验中一个重要的测量参数,在大型现场火灾试验中,传统的温度判别法具有很大的局限性和缺点;本论文提出了一种采用红外对射光强衰减的方法来确定烟气层界面的高度,为大型现场火灾试验中的烟气层高度测量提供了一种更好的选择。     

微观视角下湿度对粉末显现手印影响规律探究

目的微观视角下探究湿度对粉末显现手印的影响规律。方法利用扫描电镜微观成像技术,观察分析不同湿度下粉末的微观形态、粉末显现不同湿度下手印的微观形态、粉末显现不同方法处理高湿度手印的微观形态。结果黑磁粉、金粉、银粉分别在相对湿度50%、30%、50%时开始出现吸湿结球现象,随湿度增加,粉末吸湿结球程度加剧,且三种粉末中金粉和银粉的吸湿结球程度最为严重;对不同湿度下手印显现,黑磁粉从相对湿度50%(金粉为30%、银粉为50%)的手印开始,随湿度增加,手印乳突花纹和小犁沟位置处粉末颗粒增多,纹线模糊,乳突纹线与小犁沟难以分辨,三种粉末中黑磁粉显现手印的纹线清晰程度最高;95%湿度下手印经在50%相对湿度环境中静置4h或吹风机吹干10min后进行粉末显现,纹线变清晰。结论1)湿度对粉末和手印都有影响,其中黑磁粉显现手印适用湿度范围为相对湿度50%以下(金粉为30%以下、银粉为50%以下);湿度影响程度排序:金粉>银粉>黑磁粉;2)降低手印所处环境湿度、加快手印表面空气流通均可减弱高湿度对粉末显现的影响。     

Location and Assessment of an Historic (150–160 Years Old) Mass Grave Using Geographic and Ground Penetrating Radar Investigation,NW Ireland*

Abstract: Reburial of human remains and concerns regarding pathogens and pollution prompted the search for, and assessment of, a 156-year-old graveyard. To locate this graveyard, historic and anecdotal information was compared to landscape interpretation from aerial photography. To assess and map the contents, surface collapses, metal detector indications, and ground-penetrating radar (GPR) were used. Some 170 anomalies compatible with burials were identified on 200 MHz GPR data, 84 of which coincided with surface collapses, suggesting both noncollapsed ground, subsequent infill, and multiple inhumations. The graveyard was possibly split into Roman Catholic plots with multiple inhumations; Protestant plots; and a kileen, or graveyard for the unbaptized (often children). The work serves as one approach to the location and mapping of recent and historic unmarked graves.     

Scanning Electron Microscope Analysis of Gunshot Defects to Bone: An Underutilized Source of Information on Ballistic Trauma

Recent years have seen increasing involvement by forensic anthropologists in the interpretation of skeletal trauma. With regard to ballistic injuries, there is now a large literature detailing gross features of such trauma; however, less attention has been given to microscopic characteristics. This article presents analysis of experimentally induced gunshot trauma in animal bone (Bos taurus scapulae) using full metal jacket (FMJ), soft point (SP), and captive bolt projectiles. The results were examined using scanning electron microscopy (SEM). Additional analysis was conducted on a purported parietal gunshot lesion in a human cranial specimen. A range of features was observed in these samples suggesting that fibrolamellar bone response to projectile impact is analogous to that observed in synthetic composite laminates. The results indicate that direction of bullet travel can be discerned microscopically even when it is ambiguous on gross examination. It was also possible to distinguish SP from FMJ lesions. SEM analysis is therefore recommended as a previously underexploited tool in the analysis of ballistic trauma.     

XPS法在交通事故微量物证鉴定中的应用

把x射线光电子能谱分析法应用到微量物证学中,对车体痕迹的同一性认定进行分析,从而为交通事故的鉴定,特别是疑难的重特大事故的鉴定提供一个新的思路和一种新的技术。     

Blood versus bone marrow pentobarbital concentrations

Postmortem pentobarbital levels in rabbit heart blood and bone marrow were determined and compared. The average ratio of femur marrow/blood pentobarbital concentrations in 24 rabbits was 1.06 +/- 0.05. The average percent difference between actual plasma pentobarbital concentrations and calculated plasma pentobarbital concentrations was 5.82 +/- 1.96. Concentrations were determined by gas chromatography of extracted, derivatized pentobarbital.     

Image analysis of gunshot residue on entry wounds: I – The technique and preliminary study

An automated image analysis (IA) technique has been developed to obtain a measure of the amount (i.e. number and area) of gunshot residue (GSR) particles within and around a gunshot wound. Sample preparation and IA procedures were standardised to improve the reproducibility of the IA measurements of GSR. Measurements of GSR from test firings into goat hide were enhanced by staining the barium and lead components present on the skin sections with Alizarin Red S. The amount of GSR detected on the stained skin sections was compared with backscatter electron micrographs of the same sections. The differences were deemed to be insignificant when the variability in the repeated test firings were taken into consideration. Preliminary results indicated that the decreasing relationship between firing range and the amount of GSR deposited was non-linear, and that for firing ranges of up to 20 cm the amount of GSR deposited from repeated shots fired from the same distance was highly variable.     

通讯监听证据立法之探讨

通讯监听是被我国司法实践所适用的一项技术侦查手段,但我国相关的可操作生立法却仍然阙如。本文拟从通讯监听的概念出发,在借鉴国外相关立法经验的基础上,实现对我国通讯监听证据立法的初步构想,以期使通讯监听技术侦查手段的实行真正实现合法化,并最大限度地保障公民的基本权利。