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61.
Lawsone is a 2‐substituted‐1,4‐naphthoquinone derivative, which has been proposed as an alternative to the reagents currently used for fingermark detection on porous surfaces. 2‐substituted‐anthraquinones, which contain an additional conjugated benzene ring, have a similar chemical structure to that of lawsone. In this study, a new series of 2‐substituted‐1,4‐naphthoquinones and 2‐substituted‐1,4‐anthraquinones were synthesized and completely characterized by1H NMR,13C NMR, IR, and HPLC‐TOF/MS analyses. All newly synthesized 2‐substituted‐1,4‐quinones were investigated for their ability to develop latent fingermarks on porous surfaces, and this ability was compared with that of lawsone. Each fingermark developed was graded using an established method; thus, quantitative data were attributed to each fingermark. It has been demonstrated that the 1,4 ‐ quinones react with amino acids present in latent fingermarks on selected paper surfaces to produce faint yellow‐orange impressions, which exhibit strong photoluminescence when illuminated with a forensic light source at 440 nm and observed through a red filter. None of the compounds caused background darkening. The results obtained were generally similar to those of lawsone, however, 8‐dibromo‐2‐(propylamino)naphthalene‐1,4‐dione and 5,8‐dibromo‐2‐(propylthio)naphthalene‐1,4‐dione yielded better results for copier paper and colored (blue) copier paper used in this analysis. To the best of our knowledge, this is the first study to examine the role of 1,4‐anthraquinone derivatives as potential fingermark development reagents. The results indicate that 1,4‐quinones have a potential to be used as reagents for enhancement of latent fingermarks.  相似文献   
62.
The basic logic of graduated deterrence worked fairly well against the Soviet Union, as each level of aggression was to be deterred by a matching response. But this logic has now been undermined vis-à-vis future rogue state chemical and biological attacks by the spread of dual-use technologies that can be diverted to weapons, and by decisions of the United States and other democracies to forego possession of chemical or biological weapons. This article identifies some of the serious difficulties of alternative approaches to deterring chemical or biological attacks, ranging from nuclear escalation to a reliance on supposed American advantages in conventional weapons. Lumping chemical and biological weapons together with nuclear weapons into a new category of "weapons of mass destruction" is a very imperfect solution.  相似文献   
63.
Current concerns regarding terrorism and international crime highlight the need for new techniques for detecting unknown and hazardous substances. A novel Raman spectroscopy‐based technique, spatially offset Raman spectroscopy (SORS), was recently devised for noninvasively probing the contents of diffusely scattering and opaque containers. Here, we demonstrate a modified portable SORS sensor for detecting concealed substances in‐field under different background lighting conditions. Samples including explosive precursors, drugs, and an organophosphate insecticide (chemical warfare agent surrogate) were concealed inside diffusely scattering packaging including plastic, paper, and cloth. Measurements were carried out under incandescent and fluorescent light as well as under daylight to assess the suitability of the probe for different real‐life conditions. In each case, it was possible to identify the substances against their reference Raman spectra in less than 1 min. The developed sensor has potential for rapid detection of concealed hazardous substances in airports, mail distribution centers, and customs checkpoints.  相似文献   
64.
Blood-contaminated shoeprints and footmarks contain valuable operational information as they may bind an individual who stepped in the crime scene with the incident and not merely with the location. As determining the age of a bloodstain remains a challenge, while processing the scene, it is difficult to determine whether the blood is completely, or partially, dry. Thus, executing a dye staining protocol may wash these marks away as they might still be soluble. However, to meet this challenge, it is possible to fix blood marks using heat. This study aims to find a solution for floor surfaces covered by heavier blood traces (shoeprints and footmarks). For this purpose, a new pseudo-operating device was constructed for examining the blood-fixing process of both mentioned trace types. Two trials were performed with depletion marks. The results revealed that fully developed fresh and heavily blood deposits were obtained by heating to 200°C for 7.5 min using the fixing device, followed by a staining protocol using amido black solution. The achieved sharp resolution of the examined bloody prints demonstrates that in certain cases the dehydration mechanism of heating is preferred over precipitating the proteins attributed to 5-sulfosalycilic acid; thus, reducing the risk of washing blood evidence while processing the crime scene.  相似文献   
65.
美国“9·11”事件之后,生化威胁成为世界各国所面临的恐怖威胁之一。我们应该在明确生化案件紧急处置基本原则的基础上,建立包括生化威胁识别、评估、确认以及任务执行、文件记录等方面在内的生化事件风险评估和管理模型。  相似文献   
66.
光谱成像检验技术   总被引:24,自引:11,他引:13  
光谱成像组合了光谱技术和成像技术。通过运用成像光谱仪 ,光谱成像方法可以记录被检验物体在一个较宽光谱范围内均匀密集分布的窄波段反射光或荧光亮度分布影像 ,形成含有物体亮度信息和光谱信息的光谱影像集。这种技术方法可以用于物证的形态特征检验和物质成分检验。相对传统光谱检验或成像检验技术 ,光谱成像检验的能力和效果都具有明显优势。  相似文献   
67.
文化发展是全面建设小康社会的一项重要目标,加快文化发展是当前亟待解决的重大课题。本文从分析发展文化在全面建设小康社会中的地位和作用切入,研究和探讨了新的历史阶段加快文化发展的新思路。  相似文献   
68.
大鼠死后骨骼肌FTIR光谱变化与死亡时间的关系   总被引:1,自引:0,他引:1  
黄平  刘勇  柯咏  鲁庆阳  邢博  樊拴良  王振原 《法医学杂志》2007,23(3):164-166,169
目的应用傅立叶变换红外光谱(FTIR)分析大鼠死后骨骼肌随死亡时间推移的化学降解过程,为死亡时间推断提供新的研究方法。方法大鼠断颈处死后置于(20±2)℃环境,不同的死亡时间点提取大鼠大腿骨骼肌组织,并运用FTIR光谱仪测定不同化学基团随死亡时间的变化。结果随着死亡时间的推移,大鼠骨骼肌组织不同吸收峰的峰强随着死亡时间增加呈现出四种不同的变化方式:增加、下降、稳定、波动,且不同峰强比显示了相似的时间变化趋势。结论FTIR光谱分析技术有望成为法医实践中推断死亡时间的新方法。  相似文献   
69.
One of the tasks of a forensic anthropologist is to sort human bone fragments from other materials, which can be difficult when dealing with highly fragmented and taphonomically modified material. The purpose of this research is to develop a method using handheld X‐ray fluorescence (HHXRF) spectrometry to distinguish human and nonhuman bone/teeth from nonbone materials of similar chemical composition using multivariate statistical analyses. The sample materials were derived primarily from previous studies: human bone and teeth, nonhuman bone, nonbiological materials, nonbone biological materials, and taphonomically modified materials. The testing included two phases, testing both the reliability of the instrument and the accuracy of the technique. The results indicate that osseous and dental tissue can be distinguished from nonbone material of similar chemical composition with a high degree of accuracy (94%). While it was not possible to discriminate rock apatite and synthetic hydroxyapatite from bone/teeth, this technique successfully discriminated ivory and octocoral.  相似文献   
70.
This paper focuses on the regulation of body and neural implants used in healthcare. The current state of these ICT body implants is outlined, and the adequacy of the relevant legal regime regulating these implants is assessed in light of the ongoing scientific and technological advances in this field. Regulatory gaps are discussed, with a particular emphasis placed on clinical investigations with brain computer interfaces and advanced prosthetics, in order to better understand whether such gaps reduce innovation and act as an institutional barrier that diminishes the opportunities for the development of valuable technologies. Finally, the divide between therapy/treatment and enhancement/augmentation is examined in order to distinguish between the various kinds of body implants, in terms of the rules they ought to comply with and the limits that ought to be set.  相似文献   
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