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401.
A rapid method for screening drug seizure samples for 3,6-diacetylmorphine (heroin), which consists of a simple hydrolysis procedure and flow-injection analysis with two chemiluminescence reagents, is described. Before hydrolysis, 3,6-diacetylmorphine evokes an intense response with a tris(2,2'-bipyridyl)ruthenium(III) reagent (prepared by dissolving the perchlorate salt in acetonitrile), and a relatively weak chemiluminescence response with a second reagent: potassium permanganate in an aqueous acidic polyphosphate solution. However, the permanganate reagent is extremely sensitive toward the hydrolysis products of 3,6-diacetylmorphine (i.e., 6-monoacetylmorphine and morphine). Some compounds commonly found in drug laboratories may cause false positives with tris(2,2'-bipyridyl)ruthenium(III), but do not produce the markedly increased response with the permanganate reagent after the hydrolysis procedure. The combination of these two tests therefore provides an effective presumptive test for the presence of 3,6-diacetylmorphine, which we have verified with 14 samples obtained from a forensic science laboratory.  相似文献   
402.
Criminologists have long recognized that offending and victimization share common ground. Using Gottfredson and Hirschis general theory of crime, with its emphasis on self-control as a theoretical backdrop, we examine the extent to which self-control is related to both violent offending and homicide victimization. To examine this issue, we use 5-year post-parole data on violent offending and homicide victimization from a sample of parolees from the California Youth Authority. Using rare-events logistic regression models, results indicate that self-control is related to each outcome, but that other risk factors are also uniquely related to each outcome. The implications of this study for theory and future research are addressed.To whom correspondence should be addressed: Department of Criminology, Law and Society, University of Florida, P.O. Box 115950, 201 Walker Hall, Gainesville, FL 32611-5950; Phone: +1-352-392-1025, ext. 213; E-mail: apiquero@ufl.edu  相似文献   
403.
Two aspects of efforts to disseminate an innovative computer-assisted instructional system called PLATO between 1972 and 1976 are addressed. The first pertains to the dissemination problems encountered and resolved by the system developers. The second covers dissemination modus operandi chosen by the developers to bring PLATO to the attention of large numbers of people. An ex post facto analysis of data obtained suggested PLATO developers made dissemination decisions that reflected viable dissemination theory and practice of the time, committed substantial resources to the dissemination process, and selected what appeared to be a cost-effective marketing strategy. Perhaps the most important consequence of these actions is that PLATO flourished throughout the 1970s and continues to flourish.  相似文献   
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