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A gas chromatographic (GC) fingerprint method, based on the presence or absence of six congeners, was developed for illicit cocaine samples. The fingerprint utilizes the relative abundances of these congeners towards each other, disregarding cocaine as the main constituent, and can be expressed numerically or graphically in the form of pictograms for rapid visual comparison. The method can be applied directly to a solution of the sample in chloroform, without previous workup procedures. More than 70 unrelated samples were analyzed and a great variation was observed in the parameter composition. On the other hand, a remarkable similarity could be seen between related samples. The GC fingerprint method may be considered an important contribution for sample comparison, as is exemplified by a subdivision of the analyzed samples in different categories, based on the number and types of congeners found.  相似文献   
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Correspondence     
Jan Adam 《欧亚研究》1997,49(6):1145-1146
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Despite its difficulties and inconsistencies in framing those practices andconducts recently unveiled by the press and judicial investigations whichhave caused considerable public discontent, the penal definition ofcorruption still highlights an interesting conceptual diversity across spaceand time that should not be overlooked. Most official discussions about andreferences to corruption and its volume are still framed within these hardparameters. It is, therefore, important to look at the intricacies ofcorruption as a crime in order to understand the virtues and failures ofnational repressive efforts. While crime statistics are of limited use for itsmeasurement, they can nevertheless help to interpret the way corruptionhas been treated through repressive instruments cross-nationally over aperiod of time.The aim of this paper is to assess the dynamics of the various processes ofsetting and revising penal standards to the conduct of office holders and theresults observable from the application of corruption and related offencesacross countries with different legal traditions.  相似文献   
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The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated.  相似文献   
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