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151.
The Meisenheimer anions formed from TNT in KOH solutions in alcohol or acetone were used in screening tests for TNT among possible nitro-explosives. The same reaction was used for the spectrophotometric assay of TNT in soil by CRREL (Cold Regions Research & Engineering Laboratory of the U.S. Army) method, also known as Jenkins' method, but the color stability was too dependent on the solution composition and the water tolerance was low, necessitating complete drying of soil samples (which may cause partial analyte decomposition) prior to analysis. This study reports the development of a colorimetric method based on the solid phase extraction (SPE) of the Meisenheimer anion formed from TNT and aqueous NaOH into a strongly basic anion exchange resin Dowex 1-X8 (OH(-) form). The orange-red color that developed both in the solid resin and solution phases was persistent for at least 1h. The resin was let to swell in alcohol, washed first with 1M aqueous NaOH, and then with H(2)O before use. To 5 mL of 4-400 ppm TNT solutions in 1:1 (v/v) acetone-water, 0.5 mL of 5% NaOH was added, diluted to 50 mL with 1:1 acetone-water, and the resulting solutions (containing the orange-red Meisenheimer anion of TNT) were agitated at room temperature with 0.9 g resin for < or =50 min. TNT exhibited a reasonably constant distribution coefficient between the resin and aqueous phases. The absorbance of the filtered solutions was measured against a reagent blank at 500nm. The TNT-loaded resins were regenerated with 1M HCl containing sodium sulfite. The calibration line of filtrate absorbance versus analytical concentration was linear over two orders of magnitude between 0.4 and 40 ppm TNT in final solution. Unlike Jenkins' method, the method was tolerant to 100-fold (by mass) of common soil anions like sulfate, nitrate, and chloride. The basic advantages of the developed colorimetric method over the similar CRREL/Jenkins' method may be summarized as color stability, water and common ion tolerance, lowering of the LOD, and widening of the linear range. As opposed to Jenkins' method, the charge-transfer bands characteristic to colorimetric detection were not obscured by the presence of water. The method is suitable for on-site applications, because the color developed in heterogenous solution was stabilized, and the method can be easily practiced with a portable colorimeter to large numbers of samples. 相似文献
152.
Rodríguez-Calvo MS Brion M Allegue C Concheiro L Carracedo A 《Forensic science international》2008,182(1-3):1-12
Sudden cardiac death (SCD) is one of the most common causes of death. An important number of sudden deaths, especially in the young, are due to genetic heart disorders, both with structural and arrhythmogenic abnormalities. In recent years, significant advances have been made in understanding the genetic basis of SCD. Identification of the genetic causes of sudden death is important because close relatives are also at potential risk of having a fatal cardiac condition. A comprehensive post-mortem investigation is vital to determine the cause and manner of death and provides the opportunity to assess the potential risk to the family after appropriate genetic counselling. In this paper, we present an update of the different genetic causes of sudden death, emphasizing their importance for the forensic pathologist due to his relevant role in the diagnosis and prevention of SCD. 相似文献
153.
María Bruquetas-Callejo 《South European society & politics》2020,25(1):75-98
ABSTRACT Migrants’ healthcare entitlement represents a conflictive issue in the political battlefield, with research pointing towards the determinant role of party politics in determining policy outputs. Addressing the 2012 healthcare reform and 2018 counter-reform adopted in Spain by a right-wing and left-wing government respectively and drawing on qualitative analysis of parties’ discourses and policy measures, we argue that ideological differences along the healthcare-migration nexus were overemphasised to play symbolic politics. Partisan competition had less impact on actual outputs, while clashes between the central and regional governments, path-dependent practices and opposition from multiple venues played a central role in the policymaking process. 相似文献
154.
Mar Gallego 《African and Black Diaspora: An International Journal》2020,13(1):68-79
ABSTRACTConcepts of healing and spirituality have remained crucial to generating agency and empowerment for both black women and black men, especially in their diasporic displacement from Africa to the US. Healing has been consistently deployed to fight against the systemic racism and sexism that has pervaded and continues to persist in the lives of African diasporic subjects. Placing the discussion of healing within the current debates about interdependence and spirituality, the paper traces the notion back to its African roots and enslavement times, and attempts to delineate a genealogy of healing up to the present that grounds interdependence and interconnectedness within an ‘ethics of resistance’. 相似文献
155.
Nebojša Vladisavljević 《欧亚研究》2020,72(1):8-32
AbstractThe article examines the quality of democracy in Serbia via the quantitative analysis of media discourse. It reveals robust competition, participation and accountability in the first decade after regime change, followed by major recent decline, thus showing that expert assessments from influential indices of democracy underrated democratic quality in the former period and overrated it later. Also revealed are the advantages of complementing expert assessments with those based on media discourse. The content analysis examined 1,921 coded items from print and electronic media coverage of major political conflicts at strategic points in the country’s democratisation. 相似文献
156.
157.
158.
María Verónica Pérez Asinari 《International Review of Law, Computers & Technology》2004,18(2):231-250
This paper describes the application of personal data protection rules in the process of e‐evidence handling. It focuses mainly on the application of Directive 95/46/EC rules to the digital environment. It also makes reference to the legal risks derived from the collection and processing of e‐evidence in violation of privacy and personal data protection law. 相似文献
159.
Die Eingriffsregelung
benötigte nach ihrer gesetzlichen Einführung (1976) ihre Zeit, um in der Praxis der Zulassung betroffener Projekte wirksam zu werden. Die Entwicklung erfuhr eine gravierende Korrektur dadurch, dass das Investitionserleichterungs- und Wohnbaulandgesetz 1993 das Verhältnis der Eingriffsregelung zum Baurecht speziell regelte. Nicht nur auf nationaler, sondern auch—und dies vor allem—auf EG-Ebene prägte und prägt der Schutz von natürlichen Lebensräumen und Habitaten nach der Flora-Fauna-Habitat-Richtlinie (FFH-RL) und der Vogelschutz-Richtlinie (V-RL) die Projektzulassung nachhaltig
. Insoweit geht es um einen besonders qualifizierten, gemeinschaftsrechtlich eingeforderten Gebietsschutz.
Kaum dass sich die Rechtslage insoweit zu konsolidieren beginnt, sieht sich die Praxis der Projektzulassung zunehmend vor die Aufgabe gestellt, spezifisch artenschutzrechtlichen Anforderungen Rechnung zu tragen.
Zur Bewältigung dieser Aufgabe will der nachstehende Artikel einen Beitrag leisten.
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160.
The authors describe the most popular drugs and their substitutes being used in Poland. The paper also presents the problem of developing and examining criminalistic traces in biological and some non-organic materials. 相似文献