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221.
Erythritol tetranitrate (ETN), an ester of nitric acid and erythritol, is a solid crystalline explosive with high explosive performance. Although it has never been used in any industrial or military application, it has become one of the most prepared and misused improvise explosives. In this study, several analytical techniques were explored to facilitate analysis in forensic laboratories. FTIR and Raman spectrometry measurements expand existing data and bring more detailed assignment of bands through the parallel study of erythritol [15N4] tetranitrate. In the case of powder diffraction, recently published data were verified, and 1H, 13C, and 15N NMR spectra are discussed in detail. The technique of electrospray ionization tandem mass spectrometry was successfully used for the analysis of ETN. Described methods allow fast, versatile, and reliable detection or analysis of samples containing erythritol tetranitrate in forensic laboratories.  相似文献   
222.
Abstract

Public debates on R2P one-sidedly focus on its forcible aspects. They should, however, also focus on R2P’s non-coercive aspects, which include the legal obligations to cooperate and to pursue peaceful conflict resolution, notably the obligation to undertake meaningful attempts at negotiation before coercive means are taken into consideration. After the Arab Spring erupted in Libya and Syria, other countries did not exhaust reasonable efforts to deal and negotiate with the incumbent powers, and to assist and encourage them to meet their obligations under R2P, even though negotiations are part and parcel of the R2P framework and constitute the very first step to be taken whenever a state seems to ignore its obligations under that framework.  相似文献   
223.
The opioid epidemic, impacted from the proliferation of fentanyl, has added impetus to the need to detect fentanyl, sources of fentanyl, and places where fentanyl and drugs adulterated with fentanyl are available. Many darknet marketplaces (DNMs) have rules that ban fentanyl. However, it is unclear how these affect the fentanyl market. Using the AlphaBay DNM as a case study, we conducted mixed methods qualitative research. We scraped and analyzed data from the AlphaBay I2P website using, among other methods, content and social network analysis, to uncover hidden fentanyl networks. Our research highlights the next evolution of darknet marketplaces – the migration of DNMs from Tor to I2P and the methods that can be used identify fentanyl networks, irrespective of where sites are: I2P, Tor, or multihomed on I2P and Tor. Despite its ban in the Global AlphaBay Rules, our research revealed the sale of fentanyl on the AlphaBay DNM. Unlike previous studies, our findings predominantly revealed the covert sale of fentanyl on AlphaBay and predatory vendors selling illicit drugs, which unbeknownst to buyers, contained fentanyl. To a lesser extent, our findings identified the overt sale of fentanyl patches on AlphaBay. Although we examined only one DNM, the prevalence of the covert sale of fentanyl and the presence of predatory vendors underscores the importance of research that decodes the language of vendors who surreptitiously sell fentanyl or drugs adulterated with fentanyl or other illicit substances. The results of our research can inform strategies aimed at disrupting and dismantling DNM fentanyl networks.  相似文献   
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225.
陆琪 《科技与法律》2014,(3):445-454
非法集资在互联网金融兴起的背景下呈现进一步多发的态势,且呈现出一些新的特征。监管机关和司法机构对非法集资的管制和处罚也进一步加强,这固然是有利于保护金融消费者的权益,但是过于严苛的管制和认定也与互联网金融大背景下整体放松管制的趋势相矛盾,有可能伤及无辜并遏制互联网金融的创新和活力。为此,通过总结互联网金融领域非法集资的犯罪特征,深入解读最新的司法解释,将有助于完善非法集资的防控体系。  相似文献   
226.
The Lisbon Treaty sets ambitious goals for the Union in the field of external relations, but makes limited changes in the pursuit of these goals. The role of the High Representative is reinforced and an External Action Service will be set up, but decisions on the common foreign and security policy are still to be taken by consensus. The Representative and the Service will seek to facilitate the emergence of such consensus and to increase the effectiveness of its external implementation. But this can only be a gradual process, the success of which will depend largely upon the continuing political will of the member states.  相似文献   
227.
This article examines the evolution of the responsibility to protect (R2P) norm through the institutional frameworks of the African Union and the United Nations. The investigation aligns itself with recent constructivist thinking around norm evolution and contestation which holds that diverging interpretations around norms facilitate not only norm contestation, but ultimately norm acceptance. In this case different ‘meanings-in-use’ of R2P within and across both organisations reinforce the contested nature of R2P. This becomes most apparent in the prevailing confusion around the affiliated concept of the protection of civilians, which is not effectively delineated from R2P. Nevertheless R2P is found to be widely acknowledged within both organisations.  相似文献   
228.
Trace explosive test surfaces are often required for the evaluation of trace detection equipment to determine the equipment performance. Test surfaces of C‐4, Detasheet, Semtex‐H, TNT, and HMTD were prepared by transferring trace amount of explosive deposited on polytetrafluoroethylene (PTFE) transfer strips onto different surfaces (Kraft paper, hard plastic, woven fabric, and soft vinyl). The amount of explosive transferred was deduced from the amount of explosive remaining on the PTFE strips after transfer, as quantified by direct analysis using tandem mass spectrometry with thermal desorption. From the data set of over 2000 transfers, we experienced lower transfer efficiency for Semtex‐H and Detasheet, and for soft vinyl and hard plastic. However, the rapid quantification mass spectrometric method allowed the transfer efficiency to be determined for all test surfaces used in an evaluation of trace explosive detectors, thereby permitting only the test surfaces with desired transfer to be accepted for the assessment.  相似文献   
229.
目的寻找SCN2B、SCN4B基因的变异位点,探讨其与青壮年不明原因夜间睡眠中猝死(SMDS)的关系。方法提取SMDS病例组及健康对照组的基因组DNA,采用聚合酶链式反应(PCR)方法扩增SCN2B、SCN4B基因编码区外显子、外显子-内含子交界区以及3'侧翼区序列,直接行DNA测序以明确遗传变异类型。结果在病例组中共检测到4个变异位点,c.237+27AG,c.*38CT,c.174CT(p.C58C)和c.*7CT。结论本研究首次对中国人SMDS病例进行了SCN2B、SCN4B基因的检测,上述基因是否为中国人SMDS的易感基因尚有待进一步研究证实。  相似文献   
230.
为探讨旋毛虫ES抗原对RAW264.7细胞TLR2/4mRNA表达的影响,分别取经0、2、5、15、30、45μg/mL ES抗原作用24h的RAW264.7细胞和用15μg/mL ES抗原作用0、3、6、12、18、24h后的RAW264.7细胞,采用半定量PCR方法检测TLR2和TLR4mRNA的表达水平变化。结果显示,随着ES抗原浓度的升高,TLR2/4mRNA的表达量逐渐上升,15μg/mL ES抗原组与空白对照组相比差异显著(P<0.05)。在15μg/mL ES抗原作用24h内,随着作用时间的延长,TLR2/4mRNA的表达量逐渐上升,作用18h后的表达水平升高,且与空白对照组差异显著(P<0.05)。证实,ES抗原可刺激RAW264.7细胞表面受体TLR2/4表达升高,且存在一定的剂量和时间效应。  相似文献   
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