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- Bibikova, E. V., et al.
(author)
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The early crust of the Volgo-Uralian segment of the East European Craton: Isotope-geochronological zirconology of metasedimentary rocks of the Bolshecheremshanskaya Formation and their Sm-Nd model ages
- 2015
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In: Stratigraphy and Geological Correlation. - 0869-5938. ; 23:1, s. 1-23
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Journal article (peer-reviewed)abstract
- We present the results of isotope-geochronological study of metasedimentary rocks of the Bolshecheremshanskaya Formation of the Volgo-Uralian segment of the East European Craton carried out to identify their protoliths. 16 samples of high-alumina gneisses from well cores were studied using the Sm-Nd isotope method and T-Nd(DM) model ages. Accessory zircons were selected from rocks with the most ancient model ages (more 3.2 Ga) in three wells: Minnibaevskaya 20000, Novo-Elkhovskaya 20009, and Zai-Karatayskaya 12930 in South Tatarstan. The isotope U-Pb dating of 200 zircon grains was performed on a Cameca 1280 NORDSIM secondary ion mass spectrometer at the Natural History Museum (Stockholm, Sweden). The most applicable sites for analysis of zircon crystals were pre-selected based on cathodoluminescence images. The analytical results demonstrate the diversity of zircon groups in age from 3.8 to 2.6 Ga and together with geochemical features of metasedimentary rocks of the Bolshecheremshanskaya Formation suggest the heterogeneous composition and age of provenance areas under denudation. Occurrence of Eoarchean and Paleoarchean zircons in the clastic material of the protolith of the Bolshecheremshanskaya gneisses indicates the existence of Early Archean crustal terrains in Volgo-Uralia.
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| 2. |
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| 3. |
- Arkhipov, Victor P., et al.
(author)
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Dynamic and structural properties of oxyethylated isononylphenols
- 2016
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In: Mendeleev communications (Print). - : Elsevier BV. - 0959-9436 .- 1364-551X. ; 26:4, s. 355-357
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Journal article (peer-reviewed)abstract
- Diffusion coefficients, dielectric relaxation times and refraction coefficients were measured, and activation energies of translational and rotational mobilities were determined for a series of oxyethylated phenols (neonols AF9-n) p-C9H19C6H4-O(CH2CH2O)nH, n = 4, 6, 8, 9, 10, 12, at different temperatures. The results demonstrated the existence of contraction and transition phenomena that changed the structure of neonol molecules at n ∼ 9 from a zigzag to a meander form.
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| 4. |
- Pisarevsky, Sergei A., et al.
(author)
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Preface
- 2015
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In: Precambrian Research. - : Elsevier BV. - 0301-9268. ; 259, s. 1-4
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Journal article (other academic/artistic)
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