488 research outputs found
Effect of anion doping on mobility of ionic charge carriers in solid solutions based on Ba2In2O5
In the work, mobilities of oxygen and protons are determined for F --substituted solid solutions based on brownmillerite Ba 2In2O5 and their concentration dependences are analyzed. It is found that small additives of the more mobile anion (F - ions) promote an increase in oxygen mobility as a result of additional effects of repulsion of ions of different nature in the anion sublattice. Mobility of oxygen at high fluoride concentrations decreases due to the overlapping of migration paths of diffusion, as both anions, fluoride ions and oxygen ions, move via oxygen vacancies. Concentration dependences of mobility of proton carriers have a similar character, which is related to the effect of the oxygen sublattice. The anion doping method used in the work can be recommended as the general method for improvement of the transport characteristics of oxygen-ionic and protonic conductors with a perovskite-like structure. Β© 2013 Pleiades Publishing, Ltd
Electric properties of oxyfluorides Ba2In2O 5-0.5x F x with brownmillerite structure
Synthesis of fluoro-substituted substances based on brownmillerite Ba 2In2O5 is carried out. The width of the homogeneity region of the Ba2In2O5-0.5x F x (0 < x β€ 0.25) solid solution was established using X-ray analysis. Measurement of temperature dependences of conductivity in atmospheres with different partial pressure of water vapor (pH2O = 3.3 and 2 Π§ 103 Pa) showed an increase in conductivity at T β€ 550 C in a humid atmosphere, which is due to appearance of proton transport. The dependence of conductivity on partial oxygen pressure (pO2 = 0.21 Π§ 105 to 10-15 Pa) is studied in the temperature range of 500-1000 C; ion transport numbers are calculated. The method of polarization measurements was used to determine transport numbers of fluoride. Total conductivity is divided into ion (proton, oxygen, and fluoride ion) and electron components. Analysis of concentration dependences of conductivities showed that low concentrations of fluoride allow increasing both the total and partial conductivities (oxygen-ion and proton) and, besides, allow shifting the "order-disorder" phase transition by 100 C to the low temperature range. Β© 2013 Pleiades Publishing, Ltd
The Effect of Simultaneous Homo- and Heterogeneous Doping on Transport Properties of Ba2In2O5
In this article, the possibility of application of simultaneous homogeneous and heterogeneous doping has been described for the first time. The composite 0.7Ba1.95In2O4.9F0.1β
0.3Ba2 InNbO6 has been obtained by in situ solid-state method. The scanning electron microscopy and thermogravimetry investigations have beencarried out; the electrical properties have been examined. It has been proved that simultaneous homogeneous and heterogeneous doping is a prospective method for obtaining high-conductive proton electrolytes.
Keywords: brownmillerite, composite, anionic doping, fluorin
Motivation and labor values of youth: Development paradoxes
Based on the monitoring studies conducted in Tyumen oblast (2006β2016), the paper aims to examine trends and specifics of the development of labor orientations. Correlation and dispersion analysis is used to single out a number of inconsistencies reflecting immaturity of the market motivation and entrepreneurial orientation among those who were born and brought up in a market environment. Young persons with a more market-oriented type of labor motivation have fewer claims and agree to have the little they have if guarantees of stability are provided. The age when there is a break in the dominance of success and achievement motivation declines. Young people pay less attention to interesting and meaningful job. A gap between the declared value of initiative and entrepreneurship and a real commitment to creation of innovations are observed. Those who were born and raised in a market environment are eager to work Β«in the marketΒ». With a very high percentage of young people willing to work for themselves the share of actual young entrepreneurs is still very low. Β© 2018 Russian Public Opinion Research Center, VCIOM. All rights reserved
Diversity and distribution of epiphytic lichens and bryophytes on aspen (Populus tremula) in the middle boreal forests of Republic of Karelia (Russia)
The distribution of epiphytic bryophyte and lichen species growing on aspen in the middle boreal forests was studied in southern Karelia (Russia). These forests varied in time-since-disturbance from 80 to 450 years. Two hundred twenty two species of epiphytes, including 178 lichens, 32 mosses and 12 liverworts, were recorded on 192 aspen trees in forests over 24 ha, in the Karelian part of the Vodlozero National Park, Kivach Strict Nature Reserve, Kizhi Sanctuary and Petrozavodsk City. Arthonia biatoricola, A. excipienda and Biatoridium monasteriense were collected in Karelia for the first time. Eighteen rare species (lichens Anaptychia ciliaris, Arthonia vinosa, Bryoria nadvornikiana, Chaenotheca gracilenta, C. stemonea, Lecidea albofuscescens, Lobaria pulmonaria, Melanelixia subaurifera, Nephroma bellum, N. laevigatum, Phaeocalicium populneum, Ramalina thrausta, Rostania occultata, Scytinium subtile, Usnea barbata, mosses Neckera pennata, Plagiomnium drummondii and liverwort Lejeunea cavifolia) listed in the Red Data Book of Republic of Karelia (2007) were found. Relationships between epiphytic lichen and bryophyte species richness and certain environmental variables (at different trunk heights above ground and time-since-disturbance) were evaluated. Lichens and mosses on aspen trunks often occupy different ecological niches. Cover and diversity of bryophytes was high on trunk bases, while the number of lichen species and their cover were higher at a height of 1.3 m above ground level. The total number of lichen species on aspen increased on average from 40 to 60 species per ha with increasing time-since-disturbance from 100 to 450 years. A stabilization in lichen species number was observed at about 200 years since disturbance. No significant correlation was determined between bryophyte diversity on aspens and the time-since-disturbance.
Polyphenol oxidase from Pectobacterium atrosepticum: identification and cloning of gene and characteristics of the enzyme
Β© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim In the present study, we attempted to elucidate if the harmful phytopathogenic bacteria of Pectobacterium genus (P. atrosepticum) possess the enzymes for oxidation of phenolic compounds. Polyphenol oxidase (laccase) activity was revealed in P. atrosepticum cell lysates. Using bioinformatic analysis, an ORF encoding a putative copper-containing polyphenol oxidase of 241 amino acids with a predicted molecular mass of 25.9 kDa was found. This protein (named Pal1) shares significant level of identity with laccases of a new type described for several bacterial species. Cloning and expression of the pal1 gene and the analysis of corresponding recombinant protein confirmed that Pal1 possessed laccase activity. The recombinant Pal1 protein was characterized in terms of substrate specificity, kinetic parameters, pH and temperature optimum, sensitivity to inhibitors and metal content. Pal1 demonstrated alkali- and thermo-tolerance. The kinetic parameters K m and kcat for 2,6-dimethoxyphenol were 0.353 Β± 0.062 mM and 98.79 Β± 4.9 s β1 , respectively. The protein displayed high tolerance to sodium azide, sodium fluoride, NaCl, SDS and cinnamic acid. The transcript level of the pal1 gene in P. atrosepticum was shown to be induced by plant-derived phenolic compound (ferulic acid) and copper sulfate
Structural and transport characteristics of substituted bismuth niobates
The results of studying solid solutions with the composition of Bi 3Nb1 - y Zr y O7 Β± Ξ΄, Bi2.95Y0.05Nb1 - y Zr y O 7 Β± Ξ΄ (y = 0-0.5; Ξy = 0.1), and Bi 6.95Y0.05Nb2 - y Zr y O 15.5 (y = 0.1-1; Ξy = 0.1) are presented. XRD and electron microscopy with X-ray microanalysis are used to determine the homogeneity regions of solid solutions; crystallochemical parameters are calculated. It is shown that irrespective of the ratio of Bi: Nb, two cubic phases are formed at an increase in the dopant amount. One of these represents a solid solution based on Bi3NbO7 (Ξ΄-phase) and the second one is a solid solution based on Ξ΄-Bi2O3 (Ξ΄β²-phase). Conductivity of sintered samples is studied using the impedance spectroscopy technique. Introduction of yttrium into the bismuth sublattice results in no increase in conductivity of solid solutions, while in the case of the ratio of Bi: Nb = 3: 1, overall conductivity of solid solutions is somewhat higher at similar dopant concentrations. Β© 2013 Pleiades Publishing, Ltd
Extended axion electrodynamics: Optical activity induced by nonstationary dark matter
We establish a new self-consistent Einstein-Maxwell-axion model based on the
Lagrangian, which is linear in the pseudoscalar (axion) field and its
four-gradient and includes the four-vector of macroscopic velocity of the axion
system as a whole. We consider extended equations of the axion electrodynamics,
modified gravity field equations, and discuss nonstationary effects in the
phenomenon of optical activity induced by axions.Comment: 6 pages, 0 figures, accepted for publication in the Journal
Gravitation and Cosmology, reported at the 14th Russian Gravitational
Conference (Ulyanovsk, 2011
ΠΠΈΡΡΠ΅ΡΠ΅Π½ΡΠΈΠ°Π»ΡΠ½Π°Ρ Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΠΊΠ° Π»ΠΎΠΊΠ°Π»ΡΠ½ΠΎΠΉ ΡΠΎΡΠΌΡ Π³ΡΠ°Π½ΡΠ»Π΅ΠΌΠ°ΡΠΎΠ·Π° Ρ ΠΏΠΎΠ»ΠΈΠ°Π½Π³ΠΈΠΈΡΠΎΠΌ: ΠΏΠΎΡΠ°ΠΆΠ΅Π½ΠΈΠ΅ ΠΎΡΠ³Π°Π½Π° Π·ΡΠ΅Π½ΠΈΡ ΠΈ ΠΎΡΠ³Π°Π½Π° ΡΠ»ΡΡ Π° (ΡΠ°ΡΡΡ 2)
Granulomatosis with polyangiitis (GPA) is a primary vasculitis associated with antineutrophil cytoplasmic antibodies, characterized by necrotizing vasculitis with predominant involvement of small vessels of various localization and necrotizing granulomatous inflammation with multiple clinical manifestations. GPA remains one of the most severe and prognostically unfavorable systemic vasculitis. The second part of the article presents data on the differential diagnosis of the onset of the disease with the ocular and ear involvement, which requires an interdisciplinary approach and interaction between doctors of different specialties. In the refractory course of the local form of GPA, immunosuppressive therapy, including glucocorticoids and rituximab or cyclophosphamide, is advisable.ΠΡΠ°Π½ΡΠ»Π΅ΠΌΠ°ΡΠΎΠ· Ρ ΠΏΠΎΠ»ΠΈΠ°Π½Π³ΠΈΠΈΡΠΎΠΌ (ΠΠΠ) β ΠΏΠ΅ΡΠ²ΠΈΡΠ½ΡΠΉ Π²Π°ΡΠΊΡΠ»ΠΈΡ, Π°ΡΡΠΎΡΠΈΠΈΡΠΎΠ²Π°Π½Π½ΡΠΉ Ρ Π°Π½ΡΠΈΠ½Π΅ΠΉΡΡΠΎΡΠΈΠ»ΡΠ½ΡΠΌΠΈ ΡΠΈΡΠΎΠΏΠ»Π°Π·ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠΌΠΈ Π°Π½ΡΠΈΡΠ΅Π»Π°ΠΌΠΈ, Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΠ·ΡΡΡΠΈΠΉΡΡ Π½Π΅ΠΊΡΠΎΡΠΈΠ·ΠΈΡΡΡΡΠΈΠΌ Π²Π°ΡΠΊΡΠ»ΠΈΡΠΎΠΌΒ Ρ ΠΏΡΠ΅ΠΈΠΌΡΡΠ΅ΡΡΠ²Π΅Π½Π½ΡΠΌ Π²ΠΎΠ²Π»Π΅ΡΠ΅Π½ΠΈΠ΅ΠΌ ΠΌΠ΅Π»ΠΊΠΈΡ
Β ΡΠΎΡΡΠ΄ΠΎΠ² ΡΠ°Π·Π»ΠΈΡΠ½ΠΎΠΉ Π»ΠΎΠΊΠ°Π»ΠΈΠ·Π°ΡΠΈΠΈΒ ΠΈ Π½Π΅ΠΊΡΠΎΡΠΈΠ·ΠΈΡΡΡΡΠΈΠΌ Π³ΡΠ°Π½ΡΠ»Π΅ΠΌΠ°ΡΠΎΠ·Π½ΡΠΌ Π²ΠΎΡΠΏΠ°Π»Π΅Π½ΠΈΠ΅ΠΌ Ρ ΠΌΠ½ΠΎΠ³ΠΎΠ³ΡΠ°Π½Π½ΡΠΌΠΈ ΠΊΠ»ΠΈΠ½ΠΈΡΠ΅ΡΠΊΠΈΠΌΠΈΒ ΠΏΡΠΎΡΠ²Π»Π΅Π½ΠΈΡΠΌΠΈ. ΠΠΠ ΠΎΡΡΠ°Π΅ΡΡΡ ΠΎΠ΄Π½ΠΈΠΌ ΠΈΠ· ΡΠ°ΠΌΡΡ
ΡΡΠΆΠ΅Π»ΡΡ
ΠΈ ΠΏΡΠΎΠ³Π½ΠΎΡΡΠΈΡΠ΅ΡΠΊΠΈ Π½Π΅Π±Π»Π°Π³ΠΎΠΏΡΠΈΡΡΠ½ΡΡ
ΡΠΈΡΡΠ΅ΠΌΠ½ΡΡ
Π²Π°ΡΠΊΡΠ»ΠΈΡΠΎΠ².Β ΠΠΎ Π²ΡΠΎΡΠΎΠΉ ΡΠ°ΡΡΠΈ ΡΡΠ°ΡΡΠΈ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½Ρ Π΄Π°Π½Π½ΡΠ΅ ΠΎ Π΄ΠΈΡΡΠ΅ΡΠ΅Π½ΡΠΈΠ°Π»ΡΠ½ΠΎΠΉ Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΠΊΠ΅ Π΄Π΅Π±ΡΡΠ° Π·Π°Π±ΠΎΠ»Π΅Π²Π°Π½ΠΈΡ Ρ ΠΏΠΎΡΠ°ΠΆΠ΅Π½ΠΈΡ ΠΎΡΠ³Π°Π½Π° Π·ΡΠ΅Π½ΠΈΡ ΠΈ ΠΎΡΠ³Π°Π½Π° ΡΠ»ΡΡ
Π°, ΠΊΠΎΡΠΎΡΠ°Ρ ΡΡΠ΅Π±ΡΠ΅Ρ ΠΌΠ΅ΠΆΠ΄ΠΈΡΡΠΈΠΏΠ»ΠΈΠ½Π°ΡΠ½ΠΎΠ³ΠΎ ΠΏΠΎΠ΄Ρ
ΠΎΠ΄Π° ΠΈ Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΡ ΠΌΠ΅ΠΆΠ΄Ρ Π²ΡΠ°ΡΠ°ΠΌΠΈ ΡΠ°Π·Π½ΡΡ
ΡΠΏΠ΅ΡΠΈΠ°Π»ΡΠ½ΠΎΡΡΠ΅ΠΉ. ΠΡΠΈ ΡΠ΅ΡΡΠ°ΠΊΡΠ΅ΡΠ½ΠΎΠΌ ΡΠ΅ΡΠ΅Π½ΠΈΠΈ Π»ΠΎΠΊΠ°Π»ΡΠ½ΠΎΠΉ ΡΠΎΡΠΌΡ ΠΠΠ ΡΠ΅Π»Π΅ΡΠΎΠΎΠ±ΡΠ°Π·Π½Π° ΠΈΠΌΠΌΡΠ½ΠΎΡΡΠΏΡΠ΅ΡΡΠΈΠ²Π½Π°Ρ ΡΠ΅ΡΠ°ΠΏΠΈΡ, Π²ΠΊΠ»ΡΡΠ°ΡΡΠ°Ρ Π³Π»ΡΠΊΠΎΠΊΠΎΡΡΠΈΠΊΠΎΠΈΠ΄Ρ ΠΈ ΡΠΈΡΡΠΊΡΠΈΠΌΠ°Π± ΠΈΠ»ΠΈ ΡΠΈΠΊΠ»ΠΎΡΠΎΡΡΠ°ΠΌΠΈΠ΄
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