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Jack Kalpakian 《South African Journal of International Affairs》2013,20(2):79-90
Morocco is going to have to become more adept at lobbying its interests in the US if the free trade area between the two countries has a chance of success. 相似文献
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Jack Freeman 《冲突和恐怖主义研究》2013,36(11):1008-1019
The Yemeni government has fought an insurgency in the north of Yemen against a group called the Shabab al Moumineen, (Believing Youth) since 2004. The insurgency is portrayed by the Yemeni government in the press as a localized phenomenon led by the single al Houthi family and state that their ranks have been decimated by near-continuous fighting. However, the al Houthi Insurgency, led by the Shabab al Moumineen, is far more than a localized uprising: it is a full-blown insurgency–and one that Yemen's government and people may not be prepared to combat. This article explains the origin of the Shabab al Moumineen and conveys the importance of this conflict in Yemen and its potential multiple impacts on the broader Middle East. 相似文献
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The substituted benzylpiperazines, 3,4-methylenedioxybenzylpiperazine (3,4-MDBP), its regioisomer 2,3-methylenedioxybenzylpiperazine (2,3-MDBP) and four isobaric ring substituted methoxymethylbenzylpiperazines (MMBP) have almost identical mass spectra. Perfluoroacylation of the secondary amine nitrogen of these isomeric piperazines gave mass spectra with differences in relative abundance of some fragment ions. However, the spectra did not yield any unique fragments for specific identification of one isomer to the exclusion of the other compounds. Gas chromatography coupled with infrared detection (GC-IRD) provides direct confirmatory data for the structural differentiation between the six isomers. The mass spectra in combination with the vapor phase infrared spectra provide for specific confirmation of each of the isomeric piperazines. The underivatized and perfluoroacyl derivative forms of the ring substituted benzylpiperazines were resolved on the polar stationary phase Rtx-200. 相似文献
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This paper discusses the organization of the first international proficiency test (PT) programme on ketamine (K) and norketamine (NK) in hair samples. The primary objective of the programme was to evaluate the analytical capability of participating laboratories on hair analysis for K and NK via comparison of results. Authentic samples, instead of spiked samples were used in the programme to mimic the analysis of incorporated illicit drugs in real-life situations. Eight of the ten participating medical or forensic laboratories from Australia, France, Hong Kong, Italy, Singapore and the USA returned results to the organizer. Quantification methods from these laboratories were confined to GC-MS and LC-MS/MS. Performance assessment based on z-score indicated that only three laboratories achieved satisfactory results for both the analysis of K and NK. It was concluded that the overall performance of the participating laboratories was fair and there is still room for further improvement. Additional similarly designed PT programmes are recommended to be organized in order to encourage reliable measurements of illicit drugs in hair samples. Taking into account the substantial effect on the consensus values within limited number of data points, a recommendation on the provision of reference values assigned by accurate methods will be of benefit to small size PT programmes in the forensic field. 相似文献
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