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Identification of Different Forms of Cocaine and Substances Used in Adulteration Using Near‐infrared Raman Spectroscopy and Infrared Absorption Spectroscopy
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Ciro A. F. O. Penido M.Sc. Marcos Tadeu T. Pacheco Ph.D. Renato A. Zângaro Ph.D. Landulfo Silveira Ph.D. Jr. 《Journal of forensic sciences》2015,60(1):171-178
Identification of cocaine and subsequent quantification immediately after seizure are problems for the police in developing countries such as Brazil. This work proposes a comparison between the Raman and FT‐IR techniques as methods to identify cocaine, the adulterants used to increase volume, and possible degradation products in samples seized by the police. Near‐infrared Raman spectra (785 nm excitation, 10 sec exposure time) and FT‐IR‐ATR spectra were obtained from different samples of street cocaine and some substances commonly used as adulterants. Freebase powder, hydrochloride powder, and crack rock can be distinguished by both Raman and FT‐IR spectroscopies, revealing differences in their chemical structure. Most of the samples showed characteristic peaks of degradation products such as benzoylecgonine and benzoic acid, and some presented evidence of adulteration with aluminum sulfate and sodium carbonate. Raman spectroscopy is better than FT‐IR for identifying benzoic acid and inorganic adulterants in cocaine. 相似文献
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Júlia de A. Leite Marcos V.L. de Oliveira Raphael Conti Warley de S. Borges Thalles R. Rosa Paulo R. Filgueiras Valdemar Lacerda Wanderson Romão Álvaro C. Neto 《Science & justice》2018,58(5):355-365
Marijuana, a drug derived from the Cannabis sativa L. plant, is the world's most consumed illicit drug. In this paper, a total of 156 marijuana samples seized in the state of Espírito Santo (ES), Brazil were studied and analysed by proton nuclear magnetic resonance (1H NMR) spectroscopy to identify the major cannabinoids present. A crude extract of all samples was purified using high performance liquid chromatography so that these compounds could serve as reference substances. Nine fractions were obtained and analysed by 1H NMR and gas chromatography–mass spectrometry (GC–MS), with five presented cannabinoids. ?9-THC (Δ9-trans-tetrahydrocannabinol), ?9-THCA (?9-tetrahydrocannabinolic acid), ?8-THC (?8-tetrahydrocannabinol), 11-hydroxycannabinol, CBV (cannabivarin), and CBN (cannabinol) were found, and their chemical structures were confirmed by GC–MS. The latter compound was obtained with high purity (≈100%), while the others were obtained as less complex mixtures with purity higher than 75% (except for Δ8-THC). Principal component analysis (PCA) was used on the 1H NMR spectra of the 156 samples, and it was found that the samples were grouped according to the months, differentiating into two groups (from July 2014 to January 2015 and from February 2015 to July 2015), where non-grouping was observed from four macro-regions of the ES state (North, Central, Metropolitan, and South). The chemical profile of the seized samples was correlated to the 1H NMR spectrum of an isolated CBN sub-fraction, in which the group formed by samples seized in the year 2015 presented lower CBN content in the chemical composition. From the PCA score plot, two groups of samples were confirmed using the partial least squares discriminant analysis and orthogonal projections to latent structures classification methods. 相似文献
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Marcos Rodriguez Costa 《现代国际关系(英文版)》2006,16(12)
At the invitation of Cui Liru, President of China Institutes of Contemporary International Relations (CICIR), Cuban Deputy Foreign Minister Marcos Rodriguez Costa paid a visit to CICIR on November 13, 2006. Following are the contents of his speech in CICIR. 相似文献
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Marcos Pablo Moloeznik 《Trends in Organized Crime》2013,16(2):177-194
After the recognition in Mexico of a situation characterized by violence involving both non-state actors (mainly drug lords) and the state apparatus, the present research critically analyzes both the national security strategy adopted by President Felipe Calderón Hinojosa (2006–2012), which is based on the process of the militarization of public security, as well as the “new” police model proposed by the executive power that seeks to professionalize law enforcement agencies. 相似文献
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W Romão BD Sabino MI Bueno BG Vaz AC Júnior AO Maldaner EV de Castro RA Lordeiro CC Nascentes MN Eberlin R Augusti 《Journal of forensic sciences》2012,57(5):1307-1312
Normally, the identification of the LSD drug is performed by forensic laboratories, using the Ehrlich spot test. However, this is a nonspecific analysis. Additionally, the Brazilian Federal Police has identified the presence of a new compound in seized blotters: 9,10-dihydro-LSD, an uncontrolled substance. In this work, easy ambient sonic-spray ionization mass spectrometry in the positive ion mode, EASI(+)-MS, was used to characterize LSD and 9,10-dihydro-LSD compositions directly from the surface of blotters. The presence of LSD in the seized blotter samples were also confirmed via high-performance liquid chromatography with ultraviolet detector. In a set of 41 blotters analyzed by EASI(+)-MS, 28 showed positive results for LSD, seven for 9,10-dihydro-LSD, and another six samples showed negative results for both LSD and 9,10-dihydro-LSD. The combination of thin layer chromatography with EASI-MS also demonstrated to be a relatively simple and powerful screening tool for forensic analysis of street drugs. 相似文献
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Renato Evando M. Filho M.S José Júlio C. Sidrim Ph.D. Rossana de A. Cordeiro Ph.D. Erica P. Caetano B.Sc. Marcos Fabio G. Rocha Ph.D. Raimunda Sâmia N. Brilhante Ph.D. 《Journal of forensic sciences》2010,55(5):1359-1361
Abstract: Despite the substantial literature on mycology, there are still limited reports of the interaction between fungi and human hosts in the postmortem period. Thus, the main goal of this study was to investigate the in vitro perforation test using Trichophyton mentagrophytes on hair from adult corpses in the postmortem period (gaseous period). The protocol was carried out with positive (prepubescent children’s hair) and negative controls (healthy adult hair) as well. One strain of Trichophyton rubrum was also used as a negative perforation control. Perforations were found in all the hair samples from corpses and prepubescent children after 12–14 days exposure to T. mentagrophytes and were absent in the hair samples of healthy adults. Furthermore, hair perforation was not observed with T. rubrum. Our preliminary findings suggest the use of T. mentagrophytes as a potential marker of the death interval in forensic science. 相似文献
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Luiz Antonio Lira M.Sc. Marcos Patrício Macedo M.Sc. José Roberto Pujol‐Luz Ph.D. Simão Dias Vasconcelos Ph.D 《Journal of forensic sciences》2019,64(3):799-804
Oxelytrum discicolle is a carrion beetle commonly found in the Neotropical region, mainly associated with cadavers and carcasses. Information on behavior related to the likelihood of cadaver colonization is scarce. We performed two field experiments in peri‐urban forest in Brazil in order to strengthen our knowledge on O. discicolle behavior. In the first experiment, we assessed the preference for piglet carcasses at different stages of decomposition offered simultaneously in two seasons, dry and rainy, while in the second experiment we investigated the diel activity of adults. A total of 493 adults were collected in the experiments. A significantly higher abundance was detected in the rainy season. There was a marked preference for carcasses at advanced stages. Adults exhibited a typical nocturnal behavior, the number trapped at night was 17 times greater than those collected during the day. Oxelytrum discicolle is nocturnal species that prefers carcasses in advanced stage of decomposition. 相似文献