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The use of cyclohexanone as a "derivatizing" reagent for the GC-MS detection of amphetamines and ephedrines in seizures and the urine 总被引:1,自引:0,他引:1
El-Haj BM Al-Amri AM Hassan MH Ali HS Bin Khadem RK 《Forensic science international》2003,135(1):16-26
A GC-MS method has been developed for the detection of amphetamine, methamphetamine, and the ephedrines, in seizures and the urine, based on on-GC condensation (derivatization) with cyclohexanone. The method is simple: the dried seizure material or the urine extract was mixed with cyclohexanone and injected into the GC-MS. The method was found to be superior to the methods based on acyl and trimethylsilyl (TMS) derivatization. Unlike for the acyl and TMS derivatives, the molecular and fragment ions of the cyclohexanone condensation products (cyclohexanone derivatives) were of substantial abundance, a useful property in unambiguous compound characterization. Furthermore, the high stability of the "derivatizing" reagent, cyclohexanone, compared with acyl and TMS derivatizing reagents, is a useful property in method development. The present method has proved selective and, tentatively, sensitive enough in the following areas (where methods based on acyl and TMS derivatization, as tested in this laboratory, have failed): (a) detection of amphetamine as a metabolite of methamphetamine; (b) detection of norpseudoephedrine as a metabolite of pseudoephedrine; (c) detection of amphetamine as an impurity of methamphetamine; (d) detection of cathine (norephedrine) as a constituent of Khat leaves; and (e) differentiation of Khat use from phenylpropanolamine use. 相似文献
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A Study of the Presence of Gunshot Residue in Pittsburgh Police Stations using SEM/EDS and LC‐MS/MS 下载免费PDF全文
Leah Ali M.S. Kyle Brown B.A. Holly Castellano M.S. Stephanie J. Wetzel Ph.D. 《Journal of forensic sciences》2016,61(4):928-938
Due to possible secondary transfer of gunshot residue (GSR) onto a suspect in police custody prior to sampling, a baseline must be created for the amount of GSR present. With an increase of “lead free” ammunition, testing for both gunpowder and primer GSR is relevant. Seventy samples were collected using carbon‐coated adhesive stubs from four Pittsburgh Police Stations and vehicles to investigate these locations as sources of secondary GSR contamination. These seventy samples were analyzed for primer GSR using scanning electron microscopy‐energy‐dispersive X‐ray spectrometry. One primer GSR particle was detected; no sample was classified as positive for primer GSR. These same samples were then analyzed for gunpowder GSR using liquid chromatography coupled to tandem mass spectrometry to test for akardite II, ethylcentralite, diphenylamine, N‐nitrosodiphenylamine, 2‐nitrodiphenylamine, and 4‐nitrodiphenylamine. Ethylcentralite was quantifiable in two test samples. These results suggest there is a negligible potential for secondary transfer of primer and gunpowder GSR. 相似文献
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Ann-Christine Andersson Arntén Nabeel Abd Algafoor Ali Al Nima Erica Schütz Trevor Archer Danilo Garcia 《Journal of Police and Criminal Psychology》2016,31(1):2-14
The affective profile model was used to investigate individual differences in police personnel perceptions about the working climate and its influences on motivation. The Positive Affect, Negative Affect Schedule (PANAS) was used to assign police personnel, sworn and non-sworn (N = 595), to four affective profiles: self-fulfilling, low affective, high affective, and self-destructive. The work climate was assessed using the Learning Climate Questionnaire (Management Relations and Style, Time, Autonomy and Responsibility, Team Style, Opportunities to Develop, Guidelines on How to do the Job, and Contentedness). Motivation was evaluated using a modified version (to refer specifically to the individual’s work situation) of the Situational Motivation Scale (intrinsic motivation, external regulation, identified regulation, and amotivation). Self-fulfilling individuals scored higher on all work climate dimensions compared to the other three groups. Compared to low positive affect profiles, individuals with profiles of high positive affect scored higher in intrinsic motivation and identified regulation. Self-destructive individuals scored higher in amotivation. Different aspects of the work climate were related to each motivation dimension among affective profiles. Police personnel may react to their work environment depending on their affective profile. Moreover, the extent to which the work influences police personnel’s motivation is also related to the affective profile of the individual. 相似文献
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Ali Kazemi 《Social Justice Research》2016,29(1):103-118
There is a paucity of empirical research on the social psychology of justice in educational settings. A few previous studies have predominantly focused on distributive and procedural justice concerns, and knowledge about the role of what have been called informational and interpersonal justice for school outcomes is very scarce. In the present study, data from 227 eighth- and ninth-grade students who participated in a survey study were analyzed to examine the interplay between relational justice concerns (decomposed into procedural, interpersonal, and informational justice), motivation to study, and school achievement. A comprehensive theoretically grounded multi-item measure of informational justice was developed and validated. The results showed that informational justice significantly predicts school grades, and that motivation to study fully mediates this effect. Neither procedural nor interpersonal justice was associated with school grades. The implications of these results for research and practice are discussed in detail. 相似文献
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Razieh Shabani Kordshouli Andrzej Grzywacz Kamran Akbarzadeh Kamal Azam AliMohammad AliMohammadi Masoud Ghadi Pasha Mohammad Ali Oshaghi 《Science & justice》2021,61(3):227-234
Entomological material may be used to estimate the time since death occurred (postmortem interval, PMI) in forensically obscure cases. The method that is commonly used to calculate minimum post-mortem interval (mPMI, i.e., the least amount of time since one can be confident death occurred) is based on the relationship between insect development and ambient temerature. Isomegalen and isomorphen diagrams are among methods allowing to calculate the age of necorphagous insects, yet thermal summation models provide the most precise and acurate estimations. The digrams are prepared based on the length or the developmental stages of the larvae as a function of time and mean ambient temperature. A knowledge of thermal requirements, in particular lower temperature threshold (Dz) at which development of a species terminates, is of essential importance to calculate ADD (Accumulated Degree Days). In this study different temperature regimes were used to construct the isomorphen diagram, examinate changes in larval body length at different ambient temperatures and to estimate the thermal requirements for developemnt of Chrysomya albiceps, the most common dipteran species reported on human and animal cadavers in Iran. Six development events including hatching, 1st ecdysis, 2nd ecdysis, wandering, pupariation and eclosion were studied under eleven constant temperature regims (17–37 0C). The development rate of Ch. albiceps increased as temperature increased. The larval length peaked at the end of third stage and then decreased at wandering stage. The maximum larval length occurred at 72 h post oviposition at either 31, 33, or 35 °C. At 17 °C, larvae did not hatch from eggs and at 37 °C wandering larvae did not proceed to pupariation, and thus larval development were analysed at the nine left over temperatures. The development stages required at least (Dz ± SE) 13.04 ± 0.37, 14.29 ± 0.45, 15.69 ± 0.56, 15.18 ± 0.56, 14.94 ± 0.48, and 11.23 ± 0.41 °C to reach one of the successive developmentl events, respectively. The estimated thermal summation constant (k) for those the six events were 10.43 ± 0.27, 19.31 ± 0.32, 27.87 ± 1.3, 55.94 ± 1.82, 66.69 ± 3.5, and 143.52 ± 5.61 ADD accordingly. 相似文献
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