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3,4-Methylenedioxymethylamphetamine (MDMA) was prepared by three synthetic routes. Analytical data from thin-layer chromatography, gas chromatography and gas chromatographymass spectrometry of the precursors (safrole and isosafrole), intermediates (isosafrole glycol, piperonylmethylketone, N-formyl-3,4-methylenedioxymethylamphetamine, N-formyl-3,4-methylenedioxyamphetamine and 1-(3,4-methylenedioxyphenyl)-2-bromopropane), reaction by-products and the product MDMA were obtained. Further analyses of MDMA using other techniques including 1H- and 13C-nuclear magnetic resonance spectroscopy, X-ray diffraction, infrared spectroscopy, ultraviolet spectroscopy and high performance liquid chromatography were also carried out. The results were then used as reference data for the identification of MDMA in case samples and also to establish the route of synthesis of illicity prepared MDMA by the study of trace impurities. 相似文献
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Peter K. Smith Christina Salmivalli Helen Cowie 《Journal of Experimental Criminology》2012,8(4):433-441
Objectives
Recent decades have seen a focus on intervention programs to reduce school bullying, in light of the severe negative consequences of such behavior. A recent meta-analysis by Ttofi and Farrington (Journal of Experimental Criminology 7: 27?C56, 2011) provided encouraging findings in terms of some significant reductions in bullying and victimization achieved by many programs. They also report analyses of effect sizes associated with specific program elements and design features of the interventions. While this is an important step forward, we critique some of the strong policy implications which they draw from these latter analyses.Methods
We discuss four important areas to substantiate this critique: analytical procedure, definitional issues, historical issues, and recent empirical data. As context, we use two particular program elements described by Ttofi and Farrington, namely use of disciplinary measures and work with peers, and one design feature, namely age of pupils.Results
The findings for the program elements and design feature examined are complex and do not justify strong policy implications at this stage.Conclusions
We conclude with suggestions for future research directions. 相似文献6.
Opportunities for gambling in mainstream North American society have increased greatly over the past two decades. Despite the popularity of legalized gambling and attention it is receiving among social science researchers and economists, gambling within jails and prisons has been overlooked. This study utilized a semistructured interviewing procedure (Smith, 1995) to gain information about prison gambling from 11 sexual offenders on parole—all had spent significant time incarcerated. Qualitative analyses of responses suggest that offenders may gamble in various forms and for a variety of reasons, including a means of alleviating boredom, providing excitement and risk, and an opportunity to socialize. Prison gambling appears to be a complex phenomenon. A substantial amount of prison gambling seems to be associated with certain psychosocial benefits, while for a minority of cases there may be severe violence and victimization. 相似文献
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The loss of a cotter pin in the front wheel assembly of cars and trucks has been a problem for several years. This is shown by the fact that the automobile manufacturers have been committed to a 100% inspection of the process for installing them on cars and trucks. In this paper, three accident cases are presented, along with a method by which the forensic engineer can determine if a cotter pin has ever been installed on the front wheel assembly. Testing was done to show what the spindle would look like if the cotter pin had been installed properly and forcibly removed. Photographs show both the accident and test spindle for comparison. 相似文献
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