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Bondarenko B.,Gas Institute of NAS of Ukraine | Sviatenko O.,Gas Institute of NAS of Ukraine | Kotov V.,Gas Institute of NAS of Ukraine | Khovavko A.,Gas Institute of NAS of Ukraine | And 3 more authors.
International Journal of Energy for a Clean Environment | Year: 2013

In the present work, there are studied new approaches that would give the possibility to receive continuously carbon nanotubes. As the basic technology was used the process at moderate temperatures (in the range of a kinetic-thermodynamic maximum of passing of the Bell-Boudoir reaction). Products of natural gas air conversion with strictly controllable hydrogen, carbon, and oxygen potentials were used in a role of reactionary gas. Also, a possibility of carbon nanotubes manufacturing from a generator gas was explored. Maximum output of a final product has been achieved on an iron ore concentrate of the Inguletzky ore mining and processing enterprise (Krivoy Rog, Ukraine), which was used among many in the capacity of the catalyst of carbon nano-tubes formation. © 2013 by Begell House, Inc.

Claesson S.,Swedish Museum of Natural History | Bibikova E.V.,RAS Vernadsky Institute of Geochemistry and Analytical Chemistry | Shumlyanskyy L.,Swedish Museum of Natural History | Shumlyanskyy L.,Mp Semenenko Institute Of Geochemistry | And 2 more authors.
Precambrian Research | Year: 2016

Zircon occurs as a minor constituent in most differentiated magmatic rocks. Its robustness to later modification means that its isotopic and chemical composition generally records conditions prevailing when it formed, and the systematic changes in the oxygen isotope record of zircon through geological time have been used to trace the temporal evolution of crust-mantle interaction and intra-crustal recycling. Here we present U-Pb, Hf, and oxygen isotopic compositions for high grade metamorphic Archean rocks from the Dniester-Bug Series, western Ukrainian Shield. Zircon from a quartz-dominated rock is up to 3.8Ga old, and enriched in 18O compared to most previously reported values from Archean zircon. Similar values are recorded in zircon cores, which exhibit a variety of internal textures including magmatic-style oscillatory zonation, and rims. If this rock is metasedimentary and the isotope signatures in cores are primary, the zircon sources were characterized by heavier oxygen isotopic compositions than any known major area of Archean crust. Alternatively the O isotope compositions have been modified. We show that a large fraction of the analyzed zircon appear not to be modified by radiation damage, and speculate that O exchange may have taken place by diffusion during extreme metasomatic alteration of the host rock. The possibility that igneous-looking, apparently unaltered zircon may not preserve a primary oxygen isotope signature has implications for its use in the interpretation of crustal evolution, including early terrestrial geodynamics. © 2015 Elsevier B.V.

Shumlyanskyy L.,Mp Semenenko Institute Of Geochemistry | Ernst R.E.,Carleton University | Soderlund U.,Lund University | Soderlund U.,Swedish Museum of Natural History | And 3 more authors.
GFF | Year: 2016

The palaeoproterozoic Northwestern region of the Ukrainian shield hosts two compositional types of mafic dykes and associated magmatism that intruded at c. 1800–1760 Ma: (1) high-Ni dolerite dykes and layered intrusions of tholeiitic affinity and (2) high-Ti dolerite dykes of jotunitic affinity associated with anorthosite–mangerite–charnockite–granite (AMCG) suites. The jotunitic dykes represent initial melts for basic rocks of the Korosten AMCG plutonic complex, whereas tholeiitic dykes may reflect emplacement of a mantle plume and formation of a large igneous province (LIP). New U–Pb baddeleyite ages indicate that both compositional types can be coeval: the jotunitic Rudnya Bazarska dyke was emplaced at 1793 ± 3 Ma, and the Zamyslovychi tholeiitic dolerite dyke at 1789 ± 9 Ma. In our model, the mantle plume-derived tholeiitic melts (underplate) supplied heat required for melting of the mafic lower crust and the production of jotunitic melts. As formation of the jotunite melts requires pressures in the range 10–13 kbar, either a thickened crust is needed or the lower crust must be subducted, or downthrusted, into the mantle. Alternatively, emplacement and ponding of large volume of tholeiitic melts might cause delamination of the lower crust, its sinking into the mantle, and further fusion to produce jotunitic melts. © 2016 Geologiska Föreningen.

Claesson S.,Swedish Museum of Natural History | Bibikova E.,RAS Vernadsky Institute of Geochemistry and Analytical Chemistry | Shumlyanskyy L.,Swedish Museum of Natural History | Shumlyanskyy L.,Mp Semenenko Institute Of Geochemistry | And 3 more authors.
Geological Society Special Publication | Year: 2015

The oldest crust in the Ukrainian Shield occurs in the Podolian and Azov domains, which both include Eoarchaean components. U-Pb age data for Dniestr-Bug enderbites, Podolian Domain, indicate that these are c. 3.75 Ga old, and Lu-Hf isotope data indicate extraction from chondritic to mildly isotopically depleted sources with εHf up to c. +2. Nd model ages support their Eoarchaean age, while model ages for Dniestr-Bug metasedimentary gneisses indicate that these also include younger crustal material. Most of the Hf-age data for metasedimentary zircon from the Soroki greenstone belt, Azov Domain, reflects Eoarchaean primary crustal sources with chondritic to mildly depleted Hf isotope signatures at 3.75 Ga. A minor portion is derived from Mesoarchaean crust with a depleted εHf signature of c. +4 at 3.1 Ga. U-Pb zircon ages from Fedorivka greenstone belt metasediments are consistent with the Soroki age data, but also include a 2.7-2.9 Ga component. Nd whole rock model ages provide support for a younger crustal component in the latter. Both domains have been subject to Neoarchaean, c. 2.8 Ga, and Palaeoproterozoic, c. 2.0 Ga, metamorphism. The spatial distribution indicates that the Podolian and Azov domains evolved independently of each other before the amalgamation of the Ukrainian Shield. © The Geological Society of London 2015.

Dudchenko N.O.,Mp Semenenko Institute Of Geochemistry
Materialwissenschaft und Werkstofftechnik | Year: 2011

Biogenic magnetite serve for a wide range of biological functions, including the orientation of animals in the space and also play an important role in the brain functioning. We describe the synthesis and characterization of magnetite nanoparticles that are the synthetic analogues of biogenic magnetite. Magnetite nanoparticles were prepared via co-precipitation of iron (II) and iron (III) with sodium hydroxide in aqueous solution at high temperature (80°C). To avoid the oxidation of the magnetite surface, further covering of the magnetite nanoparticles with (3-aminopropyl)triethoxysilane was performed. The obtained magnetite nanoparticles had a comparatively high magnetization (45 A·m2/kg) and crystallinity. The average diameter of synthesized magnetite nanoparticles was around 14 nm. We could conclude that the characteristics of the synthesized magnetite nanoparticles (size, phase composition, magnetic properties) are similar to biogenic magnetite. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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