Yazar "Ilyin, I." seçeneğine göre listele

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    An astrometric and spectroscopic study of the ? Scuti variable HD 21190 and its wide companion CPD-83A°A 64B
    (Oxford Univ Press, 2017) Niemczura, E.; Scholz, R. -D.; Hubrig, S.; Jaervinen, S. P.; Schoeller, M.; Ilyin, I.; Alicavus, F. Kahraman
    Although pulsations of delta Scuti type are not expected among Ap stars from a theoretical point of view, previous observations of the known delta Scuti star HD 21190 indicated a spectral classification F2 III SrEuSi:, making it the most evolved Ap star known. Our atmospheric chemical analysis based on recent High Accuracy Radial velocity Planet Searcher observations confirms the presence of chemical peculiarities in HD 21190. This star is also the only target known to host a magnetic field along with its delta Scuti pulsation properties. Using an astrometric analysis, we show that HD 21190 forms a physical binary system with the companion CPD -83A degrees A 64B. The presented astrometric and spectroscopic study of the binary components is important to understand the complex interplay between stellar pulsations, magnetic fields and chemical composition.
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    Country-specific correlations across Europe between modelled atmospheric cadmium and lead deposition and concentrations in mosses
    (Elsevier Sci Ltd, 2012) Harmens, H.; Ilyin, I.; Mills, G.; Aboal, J. R.; Alber, R.; Blum, O.; Coskun, M.
    Previous analyses at the European scale have shown that cadmium and lead concentrations in mosses are primarily determined by the total deposition of these metals. Further analyses in the current study show that Spearman rank correlations between the concentration in mosses and the deposition modelled by the European Monitoring and Evaluation Programme (EMEP) are country and metal-specific. Significant positive correlations were found for about two thirds or more of the participating countries in 1990, 1995, 2000 and 2005 (except for Cd in 1990). Correlations were often not significant and sometimes negative in countries where mosses were only sampled in a relatively small number of EMEP grids. Correlations frequently improved when only data for EMEP grids with at least three moss sampling sites per grid were included. It was concluded that spatial patterns and temporal trends agree reasonably well between lead and cadmium concentrations in mosses and modelled atmospheric deposition. (C) 2012 Elsevier Ltd. All rights reserved.