试论涉爆现场紧急处置原则和程序

涉爆现场处置工作细致复杂,危险性高,一线民警必须按照一定的原则和程序,才能有条不紊,紧张而有序地做好这项工作.     

移动互联网背景下电子数据的取证审查初探

因电子数据有客观、稳定等特点,在刑事证据中扮演着重要角色。随着新刑事诉讼法将电子数据单独归类,在司法实践中,电子数据越来越得到刑事办案人员的重视。但不可否认的是,电子数据具有变化快、种类多、科技化等特点,尤其在当今的移动互联网时代,移动设备产生的电子数据越来越呈现出这种特点,并给取证方法、审查标准、采信规则等刑事司法实务带来困惑与矛盾,因而需要尽快加以解决和规范方法。     

录音设备识别司法鉴定技术研究

目标随着手机和录音笔等数字录音设备的普及,数字录音已基本取代传统的模拟录音,成为录音司法鉴定主导性检材类型。数字录音资料作为视听资料的重要组成部分,其真实性司法鉴定新技术新方法的研究具有重要的理论意义和实际应用价值。方法研究基于录音设备识别的数字录音真实性鉴定技术,通过数字录音背景噪声片段的提取,计算录音设备相关的关键统计特征,包括采样直方图分布特征和平均频谱统计特征,并使用机器学习和模式分类方法对数字录音的载体即录音设备进行准确分类。结果实验中最高的分类准确性达到97.09%。在录音设备可分性研究成果基础上,提出应用于数字录音设备司法鉴定的可行实施方案。结论研究结果表明了基于信号统计特征分析的录音设备识别方法的可行性和准确性。     

Primary and secondary skeletal blast trauma

This study examines primary (resulting from blast wave) and secondary (resulting from disintegrated, penetrating fragments) blast trauma to the skeleton. Eleven pigs were exposed to semi-controlled blast events of varying explosive type, charge size, and distance, including some cases with shrapnel. Skeletal trauma was found to be extensive, presenting as complex, comminuted fractures with numerous small, displaced bone splinters and fragments. Traumatic amputation of the limbs and cranium was also observed. Fractures were concentrated in areas nearer the blast, but there was generally no identifiable point of impact. Fractures were more random in appearance and widespread than those typically associated with gunshot or blunt force injury events. These patterns appear to be uniquely associated with blast trauma and may therefore assist forensic anthropologists and other forensic examiners in the interpretation of skeletal trauma by enabling them to differentiate between blast trauma and trauma resulting from some other cause.     

Noise Trauma Induced by a Mousetrap—Sound Pressure Level Measurement of Vole Captive Bolt Devices

Abstract: While ballistic parameters of vole captive bolt devices have been reported, there is no investigation on their hazardous potential to cause noise trauma. The aim of this experimental study was to measure the sound pressure levels of vole captive bolt devices. Two different shooting devices were examined with a modular precision sound level meter on an outdoor firing range. Measurements were taken in a semi‐circular configuration with measuring points 0° in front of the muzzle, 90° at right angle of the muzzle, and 180° behind the shooting device. Distances between muzzle and microphone were 0.5, 1, 2, 10, and 20 m. Sound pressure levels exceeded 130 dB(C) at any measuring point within the 20‐m area. Highest measurements (more than 172 dB[C]) were taken in the 0° direction at the 0.5‐m distance for both shooting devices proving the hazardous potential of these gadgets to cause noise trauma.     

Analysis of Explosives by GC‐UV

A mixture of explosives was analyzed by gas chromatography (GC) linked to ultraviolet (UV) spectrophotometry that enabled detection in the range of 178–330 nm. The gas‐phase UV spectra of 2,4,6‐trinitrotoluene (TNT), 2,4‐dinitrotoluene (DNT), ethylene glycol dinitrate (EGDN), glycerine trinitrate (NG, nitroglycerine), triacetone triperoxide (TATP), and pentaerythritol tetranitrate (PETN) were successfully recorded. The most interesting aspect of the current application is that it enabled simultaneous detection of both the target analyte and its decomposition products. At suitable elevated temperatures of the transfer line between the GC instrument and the UV detector, a partial decomposition was accomplished. Detection was made in real time and resulted in overlaid spectra of the mother compound and its decomposition product. Hence, the presented approach added another level to the qualitative identification of the explosives in comparison with traditional methods that relies only on the detection of the target analyte. As expected, the decomposition product of EGDN, NG, and PETN was NO, while TATP degraded to acetone. DNT and TNT did not exhibit any decomposition at the temperatures used.     

民爆公共安全专业人才培养探讨

民爆物品安全管理是公安机关维护社会治安稳定、强化社会治安管理、严格管制爆炸物品的重要职责和任务。公安院校培养具有民爆公共安全管理知识、理论、技能和具备良好素质的应用型专业人才,是严峻的社会治安形势对公安机关民爆物品安全管理提出的新任务、新要求。民爆公共安全专业学生应当具备科学的知识构成、精湛的岗位核心能力和养成优良的政治、法律、业务、身体、心理素质。     

Identification of Bodies by Unique Serial Numbers on Implanted Medical Devices

Visual identification is the most common identification method used by medical examiners but is not always possible. Alternative methods include X‐ray, fingerprint, or DNA comparison, but these methods require additional resources. Comparison of serial numbers on implanted medical devices is a rapid and definitive method of identification. To assess the practicality of using this method, we reviewed 608 consecutive forensic autopsies performed at a regional medical examiner office. Of these, 56 cases required an alternative method of identification due to decomposition (n = 35), gunshot wound (n = 9), blunt trauma (n = 6), or charring (n = 6). Of these 56 cases, eight (14.3%) were known to have an implanted medical device. Of these eight cases, five (63%) could be positively identified by comparing serial numbers. If an implanted medical device is known to be present, and medical records are available, identification by medical device serial number should be a first‐line method.     

Application of LC−QTOF/MS for the validation and determination of organic explosive residues on Ionscan® swabs

The identification and confirmation of trace explosive residues along with potential precursors and degradation products require a comprehensive laboratory analysis procedure. This study presents the determination of organic explosives consisting of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), 2,4,6-trinitrotoluene (TNT), 2,4,6,N-tetranitro-N-methylaniline (Tetryl), 1,3,5-trinitrobenzene (1,3,5-TNB) and pentaerythritol tetranitrate (PETN) by a high-resolution liquid chromatography quadrupole time-of-flight mass spectrometry (LC−QTOF/MS). The qualitative information including retention time, collision energy, precursor ions, and characteristic fragmentation pattern of each explosive were collected using an atmospheric pressure chemical ionization (APCI) in negative ion mode. The separation efficiency among five compounds was greatly achieved in this study. Four real explosive samples consisting of TNT, RDX, PETN and Tetryl and 12 Ionscan® quality control swabs from the Royal Thai Army were also tested to validate and verify the viability of the GC–MS method used to validate results from an Ionscan® system. The results showed that LC−QTOF/MS is a powerful technique for the identification and confirmation of thermally unstable organic explosives on Ionscan® swabs compared to a conventional GC−MS technique.     

The study and forensic significance of drill bit use indicators

Abstract:  A case study involving an improvised pipe bomb with a drilled fuse hole is presented. This case study and its accompanying research details drill bit use and/or nonuse indicators. These indicators are then further classified to develop relevant conclusion criteria. These criteria are: (1) trace deposits in the form of particulate and/or smears on the drill bit, especially inside the flute and the tip area, (2) physical damage including chipping, abrasion, and fissuring on the drill bit which mostly occurred on the flute edge bevels and lip edges, and (3) thermal damage. One or any combination of these indicators could be used as effective criteria for concluding drill bit usage. This study also determined that a drill bit produces well-defined toolmarks on swarf shavings that could be identified back to that particular tool, and there is no mechanical break-in period for obtaining reproducible toolmarks on newly manufactured or unused bits.