Mineralogical and geochemical features of the Manus Basin hydrothermal sulfide ores, Bismarck Sea

Paragenetic mineral assemblages have been established based on mineralogical, chemical, and isotope (S, Pb) studies, and the sequence of deposition has been defined in hydrothennal sulfide structures in a typical back-arc basin. The ores in the Manus basin have a prominent Zn specialization (sphalerite, würtzite, and fe-sphalerite). An association of Fe-spbalerite and galena with Ag sulfosalts is noted that is not characteristic of typical midocean ridge hydrothennal systems. The average 34S in the sulfide minerals is 3.5%o, which corresponds to the medium-temperature sphalerite stage in hydrothermal mineral fonnation. It is suggested that the metal source is located in the relatively acid rocks of the island-arc tholeiitic series and possibly in sediments

Kinetic parameters of the uranium luminescence in Lif crystals

The results of researches with nanosecond time resolution of kinetic characteristics of luminescence buildup and decay in crystals LiF(U)-O at 300 K under action of both laser pulse with energy 3,68 eV and electron pulse with energy 300 keV have been presented. Influence of excite method on kinetic characteristics of uranium luminescence buildup and influence of uranium on kinetic characteristics of oxygen luminescence in crystal were establishe

Fabrication of probes for scanning near-field optical microscopy using focused ion beam

The results were obtained using the infrastructure of the Center for Shared Use “Nanotechnology” of the Southern Federal University

Thermal stability of color centers in LiF crystals: dependence on radiation type and dose

Accumulation of radiation defects at irradiation is the complex result of consecutive and mutually independent events: formation of primary pair, spatial separation of its components and their transformation into stable ones under experimental conditions [1]..

Thermal stability of color centers in LiF crystals: dependence on radiation type and dose

Accumulation of radiation defects at irradiation is the complex result of consecutive and mutually independent events: formation of primary pair, spatial separation of its components and their transformation into stable ones under experimental conditions [1]..

Stone Age Research in the Narva–Luga Klint Bay Area in 2005–2014

The Narva–Luga micro-region, situated on the border of Estonia and Russia in north-eastern Europe, has been the target of international and interdisciplinary research conducted annually between 2005 and 2014. During this time, altogether 42 new archaeological sites have been discovered, and many sites have also been excavated – in addition, a large amount of natural scientific data has been collected. All in all, over 60 Stone Age and Bronze Age sites are currently known in this micro-region. The sites date mostly between the late 6th and late 3rd millennia calBC, that is, to the cultural contexts of Narva Ware, Comb Ware, and Corded Ware. In this paper, some of the main results of the archaeological studies made during the last decade are briefly summarised

Electrochemical amination. Ti(IV)/Ti(III) mediator system in aqueous solutions of sulfuric acid

As a result of polarographic and spectrophotometric studies, and mathematical modeling, the dependence of electrochemical properties of the Ti(IV)/Ti(III) pair on the composition of the Ti(IV) complexes is established in sulfuric acid solutions. It is found that Ti(IV) in 1-17 M H2SO 4 at the metal ion concentrations used in the process of amination of aromatic compounds can exist in the form of twelve basic complex forms, of which seven, including the binuclear and two tetranuclear ones, are observed for the first time. Ten forms are electrochemically active. An increase in the overall amount of reversibly reducing cationic mononuclear hydrosulfate complexes of Ti(IV) among these at a growing H2SO4 concentration results in an increase in the redox potential of the Ti(IV)/Ti(III) mediator system and therefore in an increase in the yield of the electrochemical amination products. © Pleiades Publishing, Ltd., 2010

Investigation of Mechanical Properties of Polyimide- Polyethyl-eneterephthalate System

The study of the physico-mechanical properties of new composite materials based on polyimide (PI) and polyethyleneterephthalate (PET) was carried out. Dependences of σ from ε for different concentrations of the second component and irradiation doses were measured. The experimental data are described satisfactorily by the exponential cascadeprobabilistic model