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721.
Niewoehner L Andrasko J Biegstraaten J Gunaratnam L Steffen S Uhlig S 《Journal of forensic sciences》2005,50(4):877-882
Within the framework of the ENFSI Expert Working Group "Firearms," every second year, a proficiency test on the detection and identification of GSR by SEM/EDX is carried out. This proficiency test is a development and extension of the previous proficiency test GSR2001. The test material was again designed by the organization panel and manufactured by an external company for SEM accessories. This time the participating laboratories were requested to determine the total number of PbSbBa containing particles on a test sample following their own laboratory specific methods of automated GSR particle search and detection by SEM/EDX. One synthetic particle sample (SPS) with artificial GSR particles was dispatched to all participants. This paper summarizes the results of the study and assesses the overall performance of the participating laboratories. Furthermore an extended statistical evaluation and a comparison with previous studies was carried out. 相似文献
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The tissue distribution of ethyl acetate and ethanol in a case of acute intoxication by ethyl acetate is presented. The victim was a 39-year-old man who was found dead lying on his abdomen in the interior of a tank containing ethyl acetate. Confirmation of ethyl acetate was obtained with static headspace gas chromatography with mass spectrometry. In blood, rapid biotransformation of ethyl acetate occurs by plasma esterases resulting in acetic acid and ethanol. Quantitation of ethyl acetate and ethanol in the postmortem samples was performed using static headspace gas chromatography with flame ionization detector. N-butanol was used as internal standard. Separation of the compounds was obtained on a Supelcowaxtrade mark-10 Fused Silica capillary column. The method was linear over the specific ranges investigated and showed a within-run accuracy of 99.8 and 101.0% and a precision of 0.5 and 2.0% for ethanol and ethyl acetate, respectively. The postmortem samples were analyzed in duplicate or triplicate. Coefficients of variation were < or =4.51% for ethyl acetate and < or =0.52% for ethanol. The low ratios of the ethyl acetate concentration to the ethanol concentration found in the postmortem tissue samples confirmed the rapid in vivo biotransformation of ethyl acetate. The highest concentration of ethyl acetate was found in the testis indicating that postmortem percutane absorption may have occurred. To our knowledge, this is the first reported tissue distribution study of ethyl acetate and ethanol in a case of acute intoxication by ethyl acetate. 相似文献
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Jan van Doorn 《European Journal on Criminal Policy and Research》1993,1(2):96-104
Conclusion In view of the enormous investments and financial interests at stake together with the necessity to maintain continuity of supply and distribution, only professional narcotic drug organizations and groups will be able to sustain a fixed share of the market. In order to gain some insight into the size of organized crime in the Netherlands, an in-depth study was conducted to this end in 1991. Police information from all over the country was gathered and analyzed. Almost 600 criminal groups appeared to be active in the Netherlands. 73 percent of them appeared to be involved in drug trafficking. Criminal networks active in Europe would be more readily identifiable if our European counterparts conducted similar into the organizational structures of criminal gangs operating in their country. If the existing plans for the creation of Europol, starting with an European Drugs Unit — a non-executive European Intelligence service in the area of narco-crime — are realized, this would be a major step forward in achieving this. 相似文献
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Jan H. Blits teaches in the University Honors Program at the University of Delaware and was previously Secretary of the Navy
Distinguished Fellow at the U.S. Naval Academy. He has published two books and numerous articles on educational and political
philosophy. 相似文献
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