Tc-Mapping and Investigation of Water-Initiated Modification of YBa2Cu3O7-x Thin Films by Low Temperature Scanning Electron Microscopy

The Tc -mapping method using low temperature scanning electron microscopy (LTSEM) has been developed to study the spatial distribution of the critical temperature in high temperature superconducting (HTSC) films with a spatial resolution approaching 2 μm. To achieve so high a spatial resolution, a numerical deconvolution method was applied that eliminated distorting effects associated with the thermal diffusion and with the contribution from the absorbed beam current. The Tc -mapping method was used to investigate modification by water of YBa2Cu3O7-x films grown on (100) MgO and (110) LaAIO3 substrates. The rate of modification of a [110]-oriented YBa2Cu3O7-x/LaAIO3 film is found to be 40 times that of a c-axis oriented YBa2Cu3O7-x/MgO epitaxial film. It is argued that water-initiated modification of the films results from penetration of hydrogen into the films, rather than from out-diffusion of oxygen

J. Petrol.

A petrological study was carried out on Mg-skarn-bearing dunite cumulates that are part of the Neo-Proterozoic Ioko-Dovyren intrusion (North Baikal region, Russia). Skarn xenoliths contain brucite pseudomorphs after periclase, forsterite and Cr-poor spinel. Fine-grained forsterite-spinel skarns occur with the brucite skarns or as isolated schlieren. Field relationships reveal that the Mg-skarns formed from silica-poor dolomitic xenoliths by interaction with the mafic magma of the Ioko-Dovyren intrusion. Rapid heating of dolomitic xenoliths by the mafic magma caused the decomposition of dolomite into calcite + periclase, releasing much CO2. Further heating quantitatively melted the calcite. A periclase-rich restite was left behind after extraction of the low-density, low-viscosity calcite melt. The extracted calcite melt mixed with the surrounding mafic melt. This resulted in crystallization of olivine with CaO contents up to 1.67 wt %. A local decrease in the silica concentration stabilized CaAl2SiO6-rich clinopyroxene. Brucite/periclase-free forsterite-spinel skarns probably originated by crystallization from the mafic melt close to the xenoliths at elevated fO(2). The high fO(2) was caused by CO2-rich fluids released during the decomposition of the xenoliths. The above case study provides the first evidence for partial melting of dolomite xenoliths during incorporation by a mafic magma

Partial melting and assimilation of dolomitic xenoliths by mafic magma: the Ioko-Dovyren intrusion (North Baikal region, Russia)

A petrological study was carried out on Mg-skarn-bearing dunite cumulates that are part of the Neo-Proterozoic Ioko-Dovyren intrusion (North Baikal region, Russia). Skarn xenoliths contain brucite pseudomorphs after periclase, forsterite and Cr-poor spinel. Fine-grained forsterite-spinel skarns occur with the brucite skarns or as isolated schlieren. Field relationships reveal that the Mg-skarns formed from silica-poor dolomitic xenoliths by interaction with the mafic magma of the Ioko-Dovyren intrusion. Rapid heating of dolomitic xenoliths by the mafic magma caused the decomposition of dolomite into calcite + periclase, releasing much CO2. Further heating quantitatively melted the calcite. A periclase-rich restite was left behind after extraction of the low-density, low-viscosity calcite melt. The extracted calcite melt mixed with the surrounding mafic melt. This resulted in crystallization of olivine with CaO contents up to 1.67 wt %. A local decrease in the silica concentration stabilized CaAl2SiO6-rich clinopyroxene. Brucite/periclase-free forsterite-spinel skarns probably originated by crystallization from the mafic melt close to the xenoliths at elevated fO(2). The high fO(2) was caused by CO2-rich fluids released during the decomposition of the xenoliths. The above case study provides the first evidence for partial melting of dolomite xenoliths during incorporation by a mafic magma

The prevalence of renewable energy in the Russian energy market

The energy crisis of 1973-1974 showed that it is difficult to constantly increase the power supply of production, based only on traditional energy sources. The power supply of society is the basis of its scientific and technological progress. It means that it is necessary to introduce unconventional, alternative energy sources more widely. Unlike fossil fuels, unconventional forms of energy are not limited to geologically reserves. Their use and consumption does not lead to the inevitable exhaustion of stocks. However, currently, the reform of world energy markets and increasing the share of renewable energy sources in their structure is a long and innovative process. Lots of countries (Russia in particular) bear significant risks because of reforming their own energy market, which causes a slight increase in the share of renewable energy sources. In this regard, the purpose of this study is to analyse the influence of environmental factors on the development of renewable energy sources in Russia. The result of this study is a system of econometric equations, which allows to evaluate the impact of changes in key drivers of the development of the renewable energy market