Application of multivariate statistical analysis for delineation of prospective geochemical anomalies in Providenskaya Area (Chukotka, Russia)

The secondary geochemical field structure was modelled on the basis of the lithogeochemical dispersion trains of the Providenskaya Area of the Chukotka Peninsula. The factor and cluster analysis were applied to interpret the nature of geochemical anomalies. It was proved that a range of anomalies were prospective for gold-silver, polymetallic, tin, and tungsten deposit allocation

A theoretical study of the structural phases of Group 5B - 6B metals and their transport properties

In order to predict the stable and metastable phases of the bcc metals in the block of the Periodic Table defined by groups 5B to 6B and periods 4 to 6, as well as the structure dependence of their transport properties, we have performed full potential computations of the total energies per unit cell as a function of the c/a ratio at constant experimental volume. In all cases, a metastable body centered tetragonal (bct) phase was predicted from the calculations. The total energy differences between the calculated stable and metastable phases ranged from 0.09 eV/cell (vanadium) to 0.39 eV/cell (tungsten). The trends in resistivity as a function of structure and atomic number are discussed in terms of a model of electron transport in metals. Theoretical calculations of the electrical resistivity and other transport properties show that bct phases derived from group 5B elements are more conductive than the corresponding bcc phases, while bct phases formed from group 6B elements are less conductive than the corresponding bcc phases. Special attention is paid to the phases of tantalum where we show that the frequently observed beta phase is not a simple tetragonal distortion of bcc tantalum

Quantum Equivalence of Massive Antisymmetric Tensor Field Models in Curved Space

We study the effective actions for massive rank-2 and rank-3 antisymmetric tensor field models in curved space-time. These models are classically equivalent to massive vector field and massive scalar field with minimal coupling to gravity respectively. We prove that effective action for massive rank-2 antisymmetric tensor field is exactly equal to one for massive vector field and effective action for massive rank-3 antisymmetric tensor field is exactly equal to one for massive scalar field. Prove is based on an identity for mass-dependent zeta-functions associated with Laplacians acting on $p$-forms.Comment: 8 pages, REVTeX fil

Organization of project activities in the system of advanced training of teachers

Project activity occupies an important place in the system of professional development. Focused on a rapidly changing environment, it provides the widest opportunities for innovative development of the field of additional education. The implementation of project activities allows you to form important for students of courses, leading decisions in the context of global educational competition and high uncertainty of the educational environment. The purpose of the article is to study the experience of organizing project activities in the system of professional development of teachers. Project activity is a joint educational creative activity of course participants that has a common goal and agreed methods to achieve it. The article reveals the experience of project activities of students in the framework of the course "Management in education". In the process of implementing project activities, the project competence of students is formed. Project activity occupies an important place in the system of professional development. Its implementation allows you to radically change the entire learning process, make it active, creative and independent.

THE ROLE OF MESOZOIC GEODYNAMIC EVENTS IN FORMATION OF SEDIMENTARY BASINS ON THE FRAMING OF THE EASTERN MONGOL-OKHOTSK OROGENIC BELT

The Mongol-Okhotsk orogenic belt, finally formed in the end of the Mesozoic as a result of later tectonic events, is divided into two flanks: western and eastern. Its formation is obviously due to a regular change in geodynamic events significantly obscured by late tectonic and magmatic processes in the western flank and more clearly defined in the eastern flank from both magmatic and stratified formations. The early changes in geodynamic environment are most clearly determined by the formation of magmatic complexes whose completion is usually accompanied by the strata formation. Stratons framing the eastern flank of the Mongol-Okhotsk orogenic belt in the Mesozoic were formed in sedimentary basins, which are currently isolated to the Krestovkinsky and Ogodzhinsky basins along the southern border and to the Strelkinsky, Malotyndinsky, Toromsky and Udsky basins along the northern border. The deposition environment varied from deep-sea marine to continental. The article attempts to correlate the cross-sections of sedimentary basins on the framing of the eastern Mongol-Okhotsk orogenic belt and considers similarity or difference in their structure, conditions of sedimentation, tectonic positions and dependence of their evolution on geodynamic processes in the regio

The soft and the hard pomerons in hadron elastic scattering at small t

We consider simple-pole descriptions of soft elastic scattering for pp, pbar p, pi+ p, pi- p, K+ p and K- p. We work at t and s small enough for rescatterings to be neglected, and allow for the presence of a hard pomeron. After building and discussing an exhaustive dataset, we show that simple poles provide an excellent description of the data in the region - 0.5 GeV^2 < t < -0.1 GeV^2, 6 GeV<sqrt(s)< 63 GeV. We show that new form factors have to be used, and get information on the trajectories of the soft and hard pomerons.Comment: 27 pages, 9 figures, LaTeX. A few typos fixed, and references correcte

Structural and magnetic properties of the (001) and (111) surfaces of the half-metal NiMnSb

Using the full potential linearised augmented planewave method we study the electronic and magnetic properties of the (001) and (111) surfaces of the half-metallic Heusler alloy NiMnSb from first-principles. We take into account all possible surface terminations including relaxations of these surfaces. Special attention is paid to the spin-polarization at the Fermi level which governs the spin-injection from such a metal into a semiconductor. In general, these surfaces lose the half-metallic character of the bulk NiMnSb, but for the (111) surfaces this loss is more pronounced. Although structural optimization does not change these features qualitatively, specifically for the (111) surfaces relaxations can compensate much of the spin-polarization at the Fermi surface that has been lost upon formation of the surface.Comment: 18 pages, 8 figure

Light absorption by polar and non-polar aerosol compounds from laboratory biomass combustion

Fresh and atmospherically aged biomass-burning (BB) aerosol mass is mostly comprised of strongly light-absorbing black carbon (BC) and of organic carbon (OC) with its light-absorbing fraction – brown carbon (BrC). There is a lack of data on the physical and chemical properties of atmospheric BB aerosols, leading to high uncertainties in estimates of the BB impact on air quality and climate, especially for BrC. The polarity of chemical compounds influences their fate in the atmosphere including wet/dry deposition and chemical and physical processing. So far, most of the attention has been given to the water-soluble (polar) fraction of BrC, while the non-polar BrC fraction has been largely ignored. In the present study, the light absorption properties of polar and non-polar fractions of fresh and aged BB emissions were examined to estimate the contribution of different-polarity organic compounds to the light absorption properties of BB aerosols. In our experiments, four globally and regionally important fuels were burned under flaming and smoldering conditions in the Desert Research Institute (DRI) combustion chamber. To mimic atmospheric oxidation processes (5–7 days), BB emissions were aged using an oxidation flow reactor (OFR). Fresh and OFR-aged BB aerosols were collected on filters and extracted with water and hexane to study absorption properties of polar and non-polar organic species. Results of spectrophotometric measurements (absorption weighted by the solar spectrum and normalized to mass of fuel consumed) over the 190 to 900nm wavelength range showed that the non-polar (hexane-soluble) fraction is 2–3 times more absorbing than the polar (water-soluble) fraction. However, for emissions from fuels that undergo flaming combustion, an increased absorbance was observed for the water extracts of oxidized/aged emissions while the absorption of the hexane extracts was lower for the aged emissions for the same type of fuels. Absorption Ångström exponent (AAE) values, computed based on absorbance values from spectrophotometer measurements, were changed with aging and the nature of this change was fuel dependent. The light absorption by humic-like substances (HULIS) was found to be higher in fuels characteristic of the southwestern USA. The absorption of the HULIS fraction was lower for OFR-aged BB emissions. Comparison of the light absorption properties of different-polarity extracts (water, hexane, HULIS) provides insight into the chemical nature of BB BrC and its transformation during oxidation processes