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OSIPOV S. N. GANDZHA S. I. ANDRIYENKO O. V. KARPOV M. V. KOSTIK R. I. 《Solar physics》1997,172(1-2):361-370
The primary shortcomings of existing methods for spectrophotometry of the Sun as a star are discussed. A new observational method is proposed. This method is based on a repeated scanning of the Sun's image while summing the signal of each step across the solar disk. A device for precise spectrophotometry of the Sun as a star has been developed around a double-pass spectrograph. This device and its operation algorithm are described. Errors caused by scanning irregularities and seeing are estimated. Several Sun-as-a-star spectrum line profiles and their bisectors are presented and compared with the same ones from the Kitt Peak FTS solar flux atlas. 相似文献
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PIM DE KLERK NORMAN DONNER HANS JOOSTEN NIKOLAY S. KARPOV MERTEN MINKE NINA SEIFERT MARTIN THEUERKAUF 《Boreas: An International Journal of Quaternary Research》2009,38(1):39-58
Fine-scaled distribution patterns of vegetation and palynomorphs in a polygon mire in NE Siberia were studied in 31 × 31 plots of 1 m2 (vegetation) and along a transect at intervals of 1 m (palynomorphs). Pollen and non-pollen-palynomorph contents clearly reflect differences between polygon ridges and centres. For most single pollen types, however, no unambiguous relation with actual plant abundances and distribution exists. High pollen values are restricted to the immediate vicinity of the pollen sources, which is attributed to the low height of the vegetation. For several plant taxa, high pollen values were found to be restricted to particular plant specimens in the population. High values of pollen ascribed to taxa currently absent at the relevant plot show that the sampled mosses contain a pollen signal of several years. Betula exilis produces two morphologically clearly distinct pollen types. The distribution of selected non-pollen palynomorphs correlates to microrelief, moisture regime and/or trophic conditions. The study shows that single palaeo-sections from arctic peatlands should not be over-interpreted with respect to their palaeoecological value. Local vegetation types and site conditions, however, can be accurately reconstructed from the total assemblages and from combined occurrences of specific palynomorph types. 相似文献
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