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191.
Four new impurities have recently been detected in the gas chromatographic signature profiles of many illicit cocaine hydrochloride exhibits. These impurities are only seen in exhibits that have been oxidized and are most prominent in samples that have been highly oxidized. Exhibits containing these compounds were subjected to gas and liquid chromatographic-mass spectrometric analyses to determine the identity of the impurities. These impurities were subsequently synthesized to verify their structures. Four diastereomeric diols formed from the oxidation of cis- and trans-cinnamoylcocaine were characterized by nuclear magnetic resonance spectrometry, mass spectrometry, and synthesis. Oxidation of cis-cinnamoylcocaine in neutral conditions yielded (2R,3R)-dihydroxy-3-phenylpropionylecgonine methyl ester and (2S,3S)-dihydroxy-3-phenylpropionylecgonine methyl ester, while trans-cinnamoylcocaine produced (2R,3S)-dihydroxy-3-phenylpropionylecgonine methyl ester and (2S,3R)-dihydroxy-3-phenylpropionylecgonine methyl ester. The recent appearance of these new impurities suggests that some illicit cocaine processors have modified their oxidation procedures of crude cocaine base for transformation into illicit refined cocaine hydrochloride. 相似文献
192.
Netherlands International Law Review - This article is occasioned by this year’s visit of the Institut de droit international to The Hague. It addresses the seminal role that the Institut (f.... 相似文献
193.
Youths' opinions about the police matter and can affect officers' ability to perform their duties. The relationship between police officers and youths, however, is often highly strained. Despite the importance of trust in effective police programming, little is known about youngsters' trust in the police and the association between trust and other views and experiences of adolescents. In a quantitative multivariate model, the current study assessed several correlates of Stoutland's (2001) dimensions of police trust in a large sample of Chicago youths. The study examined the relationship between youths' trust in the police and their attitudes, beliefs, experiences, behaviors, and background characteristics. Supportive of Stoutland's (2001) results, the investigation found that trust in the police was a multidimensional construct. The current study also found a relationship between vicarious experiences and trust and evidence for the negativity or asymmetrical bias that has appeared in previous studies of police-citizen contacts. 相似文献
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Arthur Fisher 《Society》1992,29(5):67-79
Arthur Fisher is science editor of Popular Science Magazine.He is a director of the Council for the Advancement of Science Writing. 相似文献
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Alvin Y. So Louis A. Picard W. Marvin Will Winston H. Griffith Robert Bianchi Richard Sisson Manochehr Dorraj Roger Mark Selya Vijayan K. Pillai Walter Opello David Felix Kathleen M. Langley Assefa Mehretu Garth T. Katner Roger E. Kanet Smart A. Ekpo Arthur Jay Klinghoffer Jorge I. Domínguez Gregory T. Papanikos 《Studies in Comparative International Development (SCID)》1991,26(1):72-111
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Arthur Nieuwendijk 《Journal of Indian Philosophy》1992,20(4):377-418
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