排序方式: 共有29条查询结果,搜索用时 15 毫秒
1.
2.
3.
Andrzej Kwiatkowski M.Eng. Małgorzata Czerwicka Ph.D. Janusz Smulko Ph.D. Piotr Stepnowski Ph.D. 《Journal of forensic sciences》2014,59(5):1358-1363
Illegal alcoholic beverages are often introduced into market using cheap technical alcohol, which is contaminated by denatonium benzoate (Bitrex) of very small concentration. Bitrex is the most bitter chemical compound and has to be removed before alcohol consumption. The home‐made methods utilize sodium hypochlorite to disintegrate particles of denatonium benzoate in alcohol and to remove bitter taste before trading. In this experimental studies, we propose a novel method that detects in a fast way the remnants of denatonium benzoate in dubious alcohol samples by Raman spectroscopy. This method applies a portable Raman spectrometer of excitation wavelength 785 nm and utilizes the effect of surface‐enhanced Raman spectroscopy (SERS) to recognize the suspected alcoholic beverages. High effectiveness (over 98%) of YES/NO classification of the investigated samples was observed when the nonlinear algorithm support vector machine (SVM) was exploited at carefully adjusted detection parameters. The method can identify illicit alcohol within minutes. 相似文献
4.
Controversial Suicide Case Using a Submachine Gun with a Sound Suppressor—The Need of Team Work of Forensic Chemistry and Firearm Examiners
下载免费PDF全文
![点击此处可从《Journal of forensic sciences》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Zuzanna Brożek‐Mucha Ph.D. Krzysztof Zdeb M.Sc. Eng. 《Journal of forensic sciences》2018,63(3):921-929
Evidence materials in a presumed suicide case were studied by a firearm examiner and a forensic chemist. The victim's body with double gunshot wounding in his forehead, a machine gun in the sustained fire mode with a silencer, and four cartridge cases were found. Examinations of the evidence, the case file studies, and experiments dedicated to the case were carried out. Relationships between the placement of cartridge cases and the gun were established using a fast camera. The distributions of gunshot residues on the evidence materials and within the comparative gunshot patterns were studied by means of optical and electron microscopy, X‐ray microanalysis, and infrared spectroscopy. The shooting distance was assessed to be 30 cm or more, whereas the greatest distance that could have been achieved by the victim himself was about 11–13 cm. The obtained results supported the version of homicide rather than suicide. 相似文献
5.
In Finland and Poland, a total of 352 (192 boys and 160 girls) 17-year-old general secondary and vocational school students participated in a study investigating their anticipated transition to adulthood. In times of large sociohistorical change in both countries, Finland (economic depression) and Poland (change from socialism to market economy), we investigated to what extent those changes were reflected in the students' probability estimations (for potential goal attainment in three future life domains; education, occupation and family life), generational comparison (attaining a life different from the life of parents), future time extension (for anticipated events in those life domains), and self-evaluations (self-esteem and control over future). The results showed that girls in both countries expressed a higher level of probability for success in education than boys did. As expected, vocational school students in both countries expressed a lower probability of success in future occupation than general secondary school students did. General secondary school students from both countries expressed higher levels of self-esteem and control over future than vocational school students did. Unexpectedly, no differences between boys' and girls' probability estimations for family life were found, in either country. However, girls from both countries anticipated an earlier and more rapid transition to adulthood than boys did, thus reflecting social time tables. The results suggested that the educational track remains a significant stratifying factor in times of societal change in both countries. 相似文献
6.
A large literature has developed in which labor market contracts are used to estimate the value of a statistical life (VSL). Reported estimates of the VSL vary substantially, from less than $100,000 to more than $25 million. This research uses meta‐analysis to quantitatively assess the VSL literature. Results from existing studies are pooled to identify the systematic relationships between VSL estimates and each study's particular features, such as the sample composition and research methods. This meta‐analysis suggests that a VSL range of approximately $1.5 million to $2.5 million (in 1998 dollars) is what can be reasonably inferred from past labor‐market studies when “best practice” assumptions are invoked. This range is considerably below many previous qualitative reviews of this literature. © 2002 by the Association for Public Policy Analysis and Management. 相似文献
7.
8.
9.
10.
Zuzanna Brożek‐Mucha Ph.D. 《Journal of forensic sciences》2009,54(3):678-681
Abstract: A reconstruction of an incident of a fatal wounding of a football fan with a parachute flare was performed. Physical and chemical examinations of the victim’s trousers and parts of a flare removed from the wound in his leg were performed by means of an optical microscope and a scanning electron microscope coupled with an energy dispersive X‐ray spectrometer. Signs of burning were seen on the front upper part of the trousers, including a 35–40 mm circular hole with melted and charred edges. Postblast residue present on the surface of the trousers contained strontium, magnesium, potassium, and chlorine. Also the case files—the medical reports and the witnesses’ testimonies—were thoroughly studied. It has been found that the evidence collected in the case supported the version of the victim being shot by another person from a distance. 相似文献