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1.
G. Simeonov A. Draganov D. Ructschev 《Journal of Thermal Analysis and Calorimetry》1994,41(1):201-209
The differential-thermal and thermogravimetric analysis of eight derivatives of 1,4-bis-(8′-hydroxy-3′,6′-disulpho-1′-naphthyl)-benzenediamide showed that these compounds have a marked exothermic effect, with maxima in the temperature range 290–340°C. The 4-nitroaniline derivative was found to undergo a blast-like decomposition in the temperature interval 285–295°C, reflected by large steps in the TG curves. The thermal analysis of diazo pigments permits determination of their applicability at higher temperatures. 相似文献
2.
G. Simeonov A. Draganov D. Rustschev 《Journal of Thermal Analysis and Calorimetry》1990,36(2):721-732
The differential-thermal and thermogravimetric analysis of eight derivatives of 1,4-bis-(5-hydroxy-7-sulpho-2naphthyl)-benzenediamide showed that these compounds have a marked exothermic effect, with maxima in the temperature range 280–330°C. The derivative of 4-nitroaniline-2-sulphonic acid were found to undergo a blast-like decomposition in the temperature intervals 255–265°C and 285–290°C, which is reflected by large steps in their TG curves.The thermal analysis of disazo pigments permits determination of their applicability at higher temperatures.
Zusammenfassung Die DT- und TG- Analyse von acht Derivaten von 1,4-bis-(5-Hydroxy-7-sulpho-2naphthyl)-benzoldiamid zeigte, dass diese Verbindungen mit einem Maximum im Temperaturbereich 280–330°C einen eindeutigen exothermen Effekt aufweisen. Derivate mit 4-Nitroanilin-2-sulfonsäure zeigen eine explosionsartige Zersetzung im Temperaturintervall 255–265°C und 285–290°C, was sich in den TG-Kurven in einer großen Stufe wiederspiegelt.Die Thermoanalyse von Bisazopigmenten ermöglicht eine Ermittlung ihrer Anwendbarkeit für höhere Temperaturen.相似文献
3.
Monitoring data from chemical analysis of rainwater and aerosol samples collected in an urban area have been interpreted by the use of environmetric approaches. An attempt was done to compare the data set structures of both type of precipitation and to estimate the contribution of different anthropogenic and naturally occurring emission sources to the total mass of the wet and dry precipitation. It was found that three latent factors explaining over 80% of the total variance of the set are responsible for the rainwater set structure-'sea spray', 'soil dust', and 'anthropogenic'. Only two were the latent factors explaining the dominant part of the variance in the case of aerosol samples-'anthropogenic' and 'natural'. It is shown that the anthropogenic influence for aerosol samples is more complex that that of rainwater samples and represents interaction between typical anthropogenic sources and natural emitters. Additionally, a source apportioning using multiple regression on absolute principal component scores is performed in order to obtain qualitative information about the impact of the different identified emission sources on the urban environment. 相似文献
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5.
Xin Hu Patricia M. Legler Noel Southall David J. Maloney Anton Simeonov Ajit Jadhav 《Journal of computer-aided molecular design》2014,28(7):765-778
Botulinum neurotoxin serotype A (BoNT/A) is the most lethal toxin among the Tier 1 Select Agents. Development of potent and selective small molecule inhibitors against BoNT/A zinc metalloprotease remains a challenging problem due to its exceptionally large substrate binding surface and conformational plasticity. The exosites of the catalytic domain of BoNT/A are intriguing alternative sites for small molecule intervention, but their suitability for inhibitor design remains largely unexplored. In this study, we employed two recently identified exosite inhibitors, D-chicoric acid and lomofungin, to probe the structural features of the exosites and molecular mechanisms of synergistic inhibition. The results showed that D-chicoric acid favors binding at the α-exosite, whereas lomofungin preferentially binds at the β-exosite by mimicking the substrate β-sheet binding interaction. Molecular dynamics simulations and binding interaction analysis of the exosite inhibitors with BoNT/A revealed key elements and hotspots that likely contribute to the inhibitor binding and synergistic inhibition. Finally, we performed database virtual screening for novel inhibitors of BoNT/A targeting the exosites. Hits C1 and C2 showed non-competitive inhibition and likely target the α- and β-exosites, respectively. The identified exosite inhibitors may provide novel candidates for structure-based development of therapeutics against BoNT/A intoxication. 相似文献
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7.
V. Simeonov 《Fresenius' Journal of Analytical Chemistry》1980,301(4):290-293
Summary The paper deals with some practically important aspects of the application of Orion ion-selective electrodes in water analysis. The effects of the salinity of sea water, sample temperature and response time on the normal electrode function are considered. It is experimentally shown that carefull checking of these factors must precede the practical use of fluoride, ammonia, chloride, nitrate and lead electrodes in sea, lake, river and drinking water samples. This is of particular importance for automatic or continuous systems, where samples with similar concentrations are analysed.
Kritische Betrachtungen zur praktischen Anwendung von Orion Ionen-selektiven Elektroden in Meer- und anderen Naturwasserproben
Zusammenfassung Einige praktisch wichtige Aspekte bei der Anwendung von Orion-Elektroden in der Wasseranalyse werden mitgeteilt. Die Einflüsse des Salzgehalts von Meerwasser, der Temperatur der Probe sowie der Einstellzeit auf die normale Funktion der Elektrode wurden untersucht. Es wurde experimentell festgestellt, daß eine sorgfältige Prüfung dieser Faktoren vor der praktische Anwendung von Fluorid-,Ammoniak-, Chlorid-, Nitrat- und Bleielektroden in Meer-, See-, Fluß- und Trinkwasser vorgenommen werden muß. Das gilt besonders für automatische oder kontinuierliche Systeme, bei denen die Konzentrationen ähnlich sind.相似文献
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9.
The low-pressure rf plasma of a secondary neutral mass spectrometer (e-gas SNMS) was connected with a time-of-flight (ToF)
mass spectrometer for the first time. As opposed to ToF–SIMS in e-gas SNMS, the primary ion pulse cannot be used for triggering
the flight time measurement. Therefore, an extraction pulse is used which at a defined time loads an ion package from the
beam of the post-ionised particles into the ToF spectrometer. The newly developed ToF–SNMS system is described, and first
experimental results are presented. 相似文献
10.
Summary An attempt is made to perform a classification of a small data set (nine unique Byzantine glass samples) by the use of different chemical component features (all components, major components, minor metallic components and colouring components). The strategy applied was cluster analysis (average and single linkage, centroid linkage). The classification using different variables has indicated that some samples have a more special position in the sample set than required by the traditional approaches of determination of similarities or dissimilarities between samples.
Klassifizierung von byzantinischen Glasproben mit Hilfe verschiedenartiger chemischer Komponenten相似文献