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Ammonium nitrate fuel oil is an explosive mixture found in most antipersonnel landmines (APL) buried throughout the Colombian territory. During more than 50 years of internal conflict, the Colombian government has found that trained dogs are the most effective method to detect APL. However, the olfactive signature in ANFO is unknown and also if there are differences in detection related to the explosive manufacturing origin. Therefore, this work begins with the analytical validation of the method used to determine ammonia, in its derivatized form as carbamate, released by home-made ANFO using HS-SPME-GC-FID. Once validated, the method was used to identify ammonia and other organic volatile compounds present in ANFO, under laboratory and simulated field conditions. The validation process includes the evaluation of the optimum conditions for the derivation and extraction of butylcarbamate, the determination of the working ranges with linear response in FID, the limits of detection and quantification, the sensitivity, and the precision. The results of the validation established linearity and sensitivity in a concentration between 20 and 120 mg/L, as well as low limits of detection and quantification of 6.4 and 21.4 mg/L, respectively. Also, an intermediate precision of 11% for butylcarbamate with a repeatability of 8%. The validated method showed in real samples of home-made ANFO besides ammonia, the presence of low molecular methylamines, and also exhibited differences in volatile compositions according to the origin. The objective of this work is to offer a reliable analytical methodology for the extraction and analysis of volatile compounds from ANFO.  相似文献   
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Responding to recent articles in Governance highlighting the need for improved measurement of bureaucratic characteristics, this article describes efforts to map Brazil's federal agencies on three dimensions—capacity, autonomy, and partisan dominance—derived from data on more than 326,000 civil servants. The article provides a “proof of concept” about the utility of agency‐level measures of these variables, demonstrating how they relate to an output common to all agencies: corruption. The article provides a first step in the direction of building a comparative research program that offers objective evaluation of bureaucracies within nation‐states, with the intent of better disentangling their impact on governance outcomes.  相似文献   
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Explanations for national success in science and technology typically focus on domestic institutions and policies. However, that line of research has yet to identify any particular set of institutions or policies that explain variation in national innovation rates across cases or over time. This article offers new evidence that the problem with domestic institutions approaches stems from their failure to consider international security factors. Specifically, this article finds a positive effect for U.S. security alliances on innovation. This finding is robust across different specifications and periods of analysis. While countries that ally militarily with the United States are found to realize benefits in economy‐wide, indigenous innovation, such an effect is not observed in military technologies. This suggests that alliances may substitute for being on the frontier in military technologies. Therefore, this article contributes not just to debates over S&T competitiveness, but also to alliance formation.  相似文献   
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This article examines the impact of Enoch Powell's speech on Britain's numerous right‐wing fringe groups and their response—in particular, that of the National Front, who benefitted the most from Powell's intervention on race and for a brief moment became Britain's fourth political party. It begins by looking at the growth of post‐World War II British fascism and how its emphasis switched from anti‐Semitism to anti‐colonial immigration. Throughout the piece, the relationship between Britain's far right and the Conservative party is examined to show how Powell inadvertently blurred the lines between the two. The article concludes with the 1979 general election victory of Margaret Thatcher who, by adopting Powellite themes but in more measured tones, destroyed the National Front's dream of an electoral breakthrough.  相似文献   
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This article discusses the representation of gender and nationality in the historical fiction of Hilda Vaughan, a Welsh woman writing in English during the early twentieth century. It offers a detailed discussion of her second novel, Here are Lovers (1926), but also makes reference to other texts. These texts are located within the historical context of the interwar period when nationality was a key issue for both feminist campaigners and emerging Welsh nationalist politics. The article draws upon the theoretical work of Williams and Foucault and argues that Vaughan's fiction offers a particularly sustained exploration of the gendering and classing of national identity.  相似文献   
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