Non-equilibrium solvation dynamics in water-DMSO binary mixture: Composition dependence of non-linear relaxation

2018 ◽  
Vol 149 (8) ◽  
pp. 084501 ◽  
Author(s):  
Milan K. Hazra ◽  
Biman Bagchi
Keyword(s):  
Binary Mixture ◽  
Composition Dependence ◽  
Linear Relaxation ◽  
Mixture Composition ◽  
Solvation Dynamics ◽  
Non Linear ◽  
Non Equilibrium

scholarly journals STUDY OF CARBON DIOXIDE ADSORPTION ON CHROMIUM OXIDE AND GALLIUM OXIDE CATALYSTS ON BASIS OF NON-LINEAR RELAXATION TIMES

2018 ◽  
Vol 61 (2) ◽  
pp. 46 ◽  
Author(s):  
Nikolay I. Kol'tsov
Keyword(s):  
Carbon Dioxide ◽  
Relaxation Time ◽  
Chromium Oxide ◽  
Rate Constants ◽  
Gallium Oxide ◽  
Relaxation Times ◽  
Oxide Catalysts ◽  
Linear Relaxation ◽  
Adsorption And Desorption ◽  
Non Linear

Recently the analysis of transient regimes of chemical reactions is paid much attention. This is due to the fact that the time-dependent relaxation modes prior to achieving steady states contain important information about the features of the reactions. During unsteady mode the changes in reactant concentrations and rate of the reaction in time are observed. These changes are due to their own relaxation processes, depending on the structure of the reaction mechanism. A complete study of the reaction mechanism involves the study of the relaxation characteristics both near and away from the stationary state. Linear relaxation time describes the local transient modes near the steady state and it is calculated as the time decrease deviations of reactant concentrations from steady-state values in the e-times. Non-linear relaxation time describes the overall behavior reactions and it can be evaluated through the reaction time from the initial state to a stationary. Depending on the structural features of reactions ratio to determine the non-linear relaxation time through of reactions parameters (rate constants stages and reactant concentrations) differ significantly. The establishment of such ratio for a particular reaction allows getting more information to identify the mechanism and the constituent rate constants of its stages. The mechanism of any catalytic reaction involves stages adsorption of one or more of the starting materials on the catalyst surface. As a rule these stages are initial remaining stages of chemical transformation of reactants adsorbed forms follow them. Therefore, it is necessary to have the data on these stages and rate constants of adsorption of reagents on the catalyst surface. Earlier by author the method for estimating the values of the rate constants of adsorption and desorption by linear relaxation times was described. This method was used for determine of mechanism and kinetic parameters of process of adsorption of carbon dioxide on the chromium oxide and gallium oxide catalysts. In this article the method for estimating the values of the rate constants of adsorption and desorption by non-linear relaxation times for this process is described. The previously found CO2 dissociative adsorption mechanism was proved by the obtained results. The intervals of values changes of the rate constants of adsorption and desorption of carbon dioxide on the gallium oxide and chromium oxide catalysts were defined.Forcitation:Kol’tsov N.I. Study of carbon dioxide adsorption on chromium oxide and gallium oxide catalysts on basis of non-linear relaxation times. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 2. P. 46-52

scholarly journals Kelvin-Helmholtz Instabilities and the Emission Knots in Herbig-Haro Jets

1997 ◽  
Vol 182 ◽  
pp. 335-342 ◽  
Author(s):  
S. Massaglia ◽  
M. Micono ◽  
A. Ferrari ◽  
G. Bodo ◽  
P. Rossi
Keyword(s):  
Numerical Simulations ◽  
Astrophysical Jets ◽  
General Applicability ◽  
Simple Assumption ◽  
Linear Evolution ◽  
Radiation Losses ◽  
Non Linear ◽  
Constant Heating ◽  
Non Equilibrium

We discuss the non-linear evolution of Kelvin-Helmholtz instabilities in Herbig-Haro jets performing numerical simulations by means of a PPM hydro-code modified as to include non-equilibrium, optically thin, radiation losses and heating. In this paper we discuss in particular the effects of different functional dependences of heating on density. The results obtained show a weak dependency of the instability evolution on the different forms of the heating function, that is largely unknown, therefore the simple assumption of constant heating, adopted in previous papers on this matter, does not lead to severe limitations on the general applicability of the results to the astrophysical jets and, in particular, to the origin of the emission knots.

Sign in / Sign up

Export Citation Format

Share Document