2,434 research outputs found
Chronopotentiometry at platinum electrode in KF-NaF-AlF3-Al2O3 melt
Some features of the mechanism of the anode process on platinum in KFβNaFβAlF3βAl2O3 melt at 750β780 Β°C depending on the of anodic current density (0.5 mA/cm2 to 2.0 A/cm2) and anodic pulse duration have been studied using chronopotentiometry method.
In curves of change in the platinum anode potential a small peak at current densities of 10β30 mA/cm2 and a clear peak at current densities of 0.5β2.0 A/cm2 are recorded when the current is cut on. Analysis of dependencies of the transition time on the current density indicates that the first peak in curve is associated with the formation of an oxide compound on the platinum surface, and
the second one is related to hindering the diffusion for delivery of electroactive particles to its surface.The study was supported by the Russian Foundation for Basic Research (grant β 13β03β00829 A)
Variation of the Dependence of the Transient Process Duration on the Initial Conditions in Systems with Discrete Time
Dependence of the transient process duration on the initial conditions is
considered in one- and two-dimensional systems with discrete time, representing
a logistic map and the Eno map, respectively.Comment: 4 pages, 2 figure
ΠΠ½ΠΎΠ΄Π½ΡΠΉ ΠΏΡΠΎΡΠ΅ΡΡ Π½Π° ΠΏΠ»Π°ΡΠΈΠ½Π΅ Π² ΡΠ°ΡΠΏΠ»Π°Π²Π΅ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ CaCl2-CaO
Methods potentiostatic polarization and cyclic voltammetry obtained new data on the mechanism and kinetics of anodic processes on platinum in the molten CaCl2-KCl-CaO when 725β775Β Β°C. Given thermodynamic values of potential difference probable total reactions in the range of the studied temperature. Using potentiostatic polarization and cyclic voltammetry obtained new data on the mechanism and kinetics of anodic process on platinum in the molten CaCl2-KCl-CaO when 725β775Β Β°C thermodynamic assessment of the probability of occurrence total reactions during electrolysis melt on the basis of CaCl2-CaO using non-carbon anode. It is shown that at high current densities anodic process takes place mainly in the conditions of slow diffusion of electrically active particles to the anode, and at low densities (up to 10 mA/cm2) to their discharge to the atomic and lecular oxygen is preceded by a stage, which can be associated with adsorption of atoms of oxygen or with the formation of an oxide film on the surface of platinum. To detect the nature of this stage, further research is needed.ΠΠ΅ΡΠΎΠ΄Π°ΠΌΠΈ ΠΏΠΎΡΠ΅Π½ΡΠΈΠΎΡΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΏΠΎΠ»ΡΡΠΈΠ·Π°ΡΠΈΠΈ ΠΈ ΡΠΈΠΊΠ»ΠΈΡΠ΅ΡΠΊΠΎΠΉ Π²ΠΎΠ»ΡΡΠ°ΠΌΠΏΠ΅ΡΠΎΠΌΠ΅ΡΡΠΈΠΈ ΠΏΠΎΠ»ΡΡΠ΅Π½Ρ Π½ΠΎΠ²ΡΠ΅ ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΠ΅ Π΄Π°Π½Π½ΡΠ΅ ΠΎ ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌΠ΅ ΠΈ ΠΊΠΈΠ½Π΅ΡΠΈΠΊΠ΅ Π°Π½ΠΎΠ΄Π½ΡΡ
ΠΏΡΠΎΡΠ΅ΡΡΠΎΠ² Π½Π° ΠΏΠ»Π°ΡΠΈΠ½Π΅ Π² ΡΠ°ΡΠΏΠ»Π°Π²Π΅ CaCl2-KCl-CaO ΠΏΡΠΈ 725β775 Β°Π‘. ΠΡΠΈΠ²Π΅Π΄Π΅Π½Ρ ΡΠ΅ΡΠΌΠΎΠ΄ΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΠΈΠ΅ Π·Π½Π°ΡΠ΅Π½ΠΈΡ ΡΠ°Π·Π½ΠΎΡΡΠΈ ΠΏΠΎΡΠ΅Π½ΡΠΈΠ°Π»ΠΎΠ² Π²Π΅ΡΠΎΡΡΠ½ΡΡ
ΡΡΠΌΠΌΠ°ΡΠ½ΡΡ
ΡΠ΅Π°ΠΊΡΠΈΠΉ Π² Π΄ΠΈΠ°ΠΏΠ°Π·ΠΎΠ½Π΅ ΠΈΡΡΠ»Π΅Π΄ΡΠ΅ΠΌΡΡ
ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡ. ΠΡΠΈ ΠΏΠΎΠΌΠΎΡΠΈ ΠΏΠΎΡΠ΅Π½ΡΠΈΠΎΡΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΏΠΎΠ»ΡΡΠΈΠ·Π°ΡΠΈΠΈ ΠΈ ΡΠΈΠΊΠ»ΠΈΡΠ΅ΡΠΊΠΎΠΉ Π²ΠΎΠ»ΡΡΠ°ΠΌΠΏΠ΅ΡΠΎΠΌΠ΅ΡΡΠΈΠΈ ΠΏΠΎΠ»ΡΡΠ΅Π½Ρ Π½ΠΎΠ²ΡΠ΅ ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΠ΅ Π΄Π°Π½Π½ΡΠ΅ ΠΎΡΠ½ΠΎΡΠΈΡΠ΅Π»ΡΠ½ΠΎ ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌΠ° ΠΈ ΠΊΠΈΠ½Π΅ΡΠΈΠΊΠΈ Π°Π½ΠΎΠ΄Π½ΠΎΠ³ΠΎ ΠΏΡΠΎΡΠ΅ΡΡΠ° Π½Π° ΠΏΠ»Π°ΡΠΈΠ½Π΅ Π² ΡΠ°ΡΠΏΠ»Π°Π²Π΅ CaCl2-KCl-CaO ΠΏΡΠΈ 725β775 Β°Π‘. ΠΡΠΎΠ²Π΅Π΄Π΅Π½Ρ ΡΠ΅ΡΠΌΠΎΠ΄ΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΎΡΠ΅Π½ΠΊΠΈ Π²Π΅ΡΠΎΡΡΠ½ΠΎΡΡΠΈ ΠΏΡΠΎΡΠ΅ΠΊΠ°Π½ΠΈΡ ΡΡΠΌΠΌΠ°ΡΠ½ΡΡ
ΡΠ΅Π°ΠΊΡΠΈΠΉ ΠΏΡΠΈ ΡΠ»Π΅ΠΊΡΡΠΎΠ»ΠΈΠ·Π΅ ΡΠ°ΡΠΏΠ»Π°Π²Π° Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ CaCl2-CaO Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ Π½Π΅ΡΠ³Π»Π΅ΡΠΎΠ΄Π½ΠΎΠ³ΠΎ Π°Π½ΠΎΠ΄Π°. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΠΏΡΠΈ Π²ΡΡΠΎΠΊΠΈΡ
ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΡΡ
ΡΠΎΠΊΠ° Π°Π½ΠΎΠ΄Π½ΡΠΉ ΠΏΡΠΎΡΠ΅ΡΡ ΠΏΡΠΎΡΠ΅ΠΊΠ°Π΅Ρ ΠΏΡΠ΅ΠΈΠΌΡΡΠ΅ΡΡΠ²Π΅Π½Π½ΠΎ Π² ΡΡΠ»ΠΎΠ²ΠΈΡΡ
Π·Π°ΠΌΠ΅Π΄Π»Π΅Π½Π½ΠΎΠΉ Π΄ΠΈΡΡΡΠ·ΠΈΠΈ ΡΠ»Π΅ΠΊΡΡΠΎΠ°ΠΊΡΠΈΠ²Π½ΡΡ
ΡΠ°ΡΡΠΈΡ ΠΊ Π°Π½ΠΎΠ΄Ρ, Π° ΠΏΡΠΈ Π½ΠΈΠ·ΠΊΠΈΡ
ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΡΡ
(Π΄ΠΎ 10 ΠΌΠ/ΡΠΌ2) ΠΈΡ
ΡΠ°Π·ΡΡΠ΄Ρ Π΄ΠΎ Π°ΡΠΎΠΌΠ°ΡΠ½ΠΎΠ³ΠΎ ΠΈ ΠΌΠΎΠ»Π΅ΠΊΡΠ»ΡΡΠ½ΠΎΠ³ΠΎ ΠΊΠΈΡΠ»ΠΎΡΠΎΠ΄Π° ΠΏΡΠ΅Π΄ΡΠ΅ΡΡΠ²ΡΠ΅Ρ ΡΡΠ°Π΄ΠΈΡ, ΠΊΠΎΡΠΎΡΠ°Ρ ΠΌΠΎΠΆΠ΅Ρ Π±ΡΡΡ ΡΠ²ΡΠ·Π°Π½Π° Ρ Π°Π΄ΡΠΎΡΠ±ΡΠΈΠ΅ΠΉ Π°ΡΠΎΠΌΠΎΠ² ΠΊΠΈΡΠ»ΠΎΡΠΎΠ΄Π° ΠΈΠ»ΠΈ Ρ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ ΠΎΠΊΡΠΈΠ΄Π½ΠΎΠΉ ΠΏΠ»Π΅Π½ΠΊΠΈ Π½Π° ΠΏΠΎΠ²Π΅ΡΡ
Π½ΠΎΡΡΠΈ ΠΏΠ»Π°ΡΠΈΠ½Ρ. ΠΠ»Ρ ΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΈΡ ΠΏΡΠΈΡΠΎΠ΄Ρ ΡΡΠΎΠΉ ΡΡΠ°Π΄ΠΈΠΈ Π½Π΅ΠΎΠ±Ρ
ΠΎΠ΄ΠΈΠΌΡ Π΄Π°Π»ΡΠ½Π΅ΠΉΡΠΈΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ
INVESTIGATION OF SILICON-CARBON NANOCOMPOSITES CONTAINING TUNGSTEN BY EXAFS-SPECTROSCOPY
The report presents results of studying the structure of tungsten-containing siliconcarbon films based on PPMS (polyphenyl methylsiloxane) by fluorescent EXAFS spectroscopy at Kurchatov synchrotron radiation source
Baikal-GVD: status and prospects
Baikal-GVD is a next generation, kilometer-scale neutrino telescope under
construction in Lake Baikal. It is designed to detect astrophysical neutrino
fluxes at energies from a few TeV up to 100 PeV. GVD is formed by multi-megaton
subarrays (clusters). The array construction started in 2015 by deployment of a
reduced-size demonstration cluster named "Dubna". The first cluster in its
baseline configuration was deployed in 2016, the second in 2017 and the third
in 2018. The full scale GVD will be an array of ~10000 light sensors with an
instrumented volume of about 2 cubic km. The first phase (GVD-1) is planned to
be completed by 2020-2021. It will comprise 8 clusters with 2304 light sensors
in total. We describe the design of Baikal-GVD and present selected results
obtained in 2015-2017.Comment: 9 pages, 8 figures. Conference proceedings for QUARKS201
Properties of iron-modified-by-silver supported on mordenite as catalysts for nox reduction
A series of mono and bimetallic catalysts based on a Fe-Ag mixture deposited on mordenite was prepared by ion-exchange and evaluated in the catalytic activity test of the de-NOx reaction in the presence of CO/C3H6. The activity results showed that the most active samples were the Fe-containing ones, and at high temperatures, a co-promoter effect of Ag on the activity of Fe catalysts was also observed. The influence of the order of cation deposition on catalysts formation and their physicochemical properties was studied by FTIR (Fourier Transform Infrared Spectroscopy) of adsorbed NO, XANES (X-ray Absorption Near-Edge Structure), and EXAFS (Extended X-ray Absorption Fine Structure) and discussed in terms of the state of iron. Results of Fe K-edge XANES oscillations showed that, in FeMOR catalysts, iron was present in a disordered state as Fe3+ and Fe2+. In FeAgMOR, the prevailing species was Fe3+, while in the AgFeMOR catalyst, the state of iron was intermediate or mixed between FeMOR and FeAgMOR. The Fe K-edge EXAFS results were characteristic of a disordered phase, the first coordination sphere being asymmetric with two different Fe-O distances. In FeAgMOR and AgFeMOR, coordination of Fe-O was similar to Fe2O3 with a few amount of Fe2+ species. We may conclude that, in the bimetallic FeAgMOR and AgFeMOR samples, a certain amount of tetrahedral Al3+ ions in the mordenite framework is replaced by Fe3+ ions, confirming the previous reports that these species are active sites for the de-NOx reaction. Based on the thermodynamic analysis and experimental data, also, it was confirmed that the order of deposition of the components influenced the mechanism of active sites’ formation during the two steps ion-exchange synthesis
A Method for Determining the Transient Process Duration in Dynamic Systems in the Regime of Chaotic Oscillations
We describe a method for determining the transient process duration in a
standard two-dimensionaldynamic system with discrete time (Henon map),
occurring in the regime of chaotic oscillationsComment: 4 pages, 2 figure
EPIDEMIOLOGICAL AND EPIZOOTIOLOGICAL ANALYSIS OF THE SITUATION ON TULAREMIA IN THE RUSSIAN FEDERATION IN 2016 AND FORECAST FOR 2017
123 cases of human infection with Francisella tularensis were registered in the territory of the Russian Federation in 2016. 90 % of the total number was reported by three Federal Districts: North-Western, Siberian, and Central ones. Epizootic manifestations of varying intensity were detected in 56 regions. A considerable number of tularemia cases were observed in the Republic of Karelia, Nenets Autonomous District, Omsk and Ryazan Regions, and in Saint-Petersburg. Conspicuous are some recent peculiarities of tularemia manifestations: non-specificity of clinical symptoms, especially at early stages of the disease, their increasing variability against the background of mixed infections with tularemia and other natural-focal infections agents. The most expressed symptoms are fever and lymphatic adenitis; the patients are diagnosed with tularemia during initial days of the sought treatment in 40-45 % of the cases. Based on the data on morbidity rates in humans, epizootiological condition of natural tularemia foci, the numbers of isolated cultures and incidence of the vectors and carriers of the agent, as well as taking into consideration the scope of preventive vaccination in the regions, identified were the territories in which epidemic complication are most likely to occur in 2017
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