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Noureddine Ouerfelli - One of the best experts on this subject based on the ideXlab platform.
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Hyperbolic Correlation between the Viscosity Arrhenius Parameters at Liquid Phase of Some Pure Newtonian Fluids and Their Normal Boiling Temperature
Russian Journal of Physical Chemistry A, 2020Co-Authors: E. Mliki, T. K. Srinivasa, A. Messaâdi, N. O. Alzamel, Z. H. A. Alsunaidi, Noureddine OuerfelliAbstract:Viscosity is the most important characteristic of hydraulic fluid and which is influenced by pressure and temperature. Using statistical methods for correlation analysis and regression, eventual causal relationship between parameters of the Arrhenius-type equation and principally the boiling point of some classical Newtonian liquids is attempted. Empirical validation utilizing data on viscosity of pure Newtonian liquids studied at atmospheric pressure and at different ranges of temperature gives excellent statistical results. Indeed, we found a significant strong correlation between the Arrhenius activation energy ( E _a), the Arrhenius temperature ( T _A), and the boiling point ( T _b). Consequently, an original hyperbole-type equation modeling this relationship is proposed which allows the prediction of the boiling temperature and the type of isobaric liquid-vapor diagram through information on viscosity Arrhenius parameters values, only in liquid phase, and will be thus very useful in the handling of engineering data especially for the study of hydraulic components and systems efficiency.
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Viscosity Arrhenius Activation Energy and Derived Partial Molar Properties in Isobutyric Acid + Water Binary Mixtures Near and Far Away from the Critical Temperature, 302.15 to 313.15 K
Journal of Solution Chemistry, 2015Co-Authors: Hassen Salhi, M. Dallel, Abdullah A. Al-arfaj, Zouheir Trabelsi, Noureddine OuerfelliAbstract:Calculations of the viscosity Arrhenius activation energy and derived partial molar properties, from literature experimental values of viscosity in isobutyric acid + water binary mixtures from 302.15 to 313.15 K, are presented here. The close similarity between the values of the Arrhenius activation energy E a and the enthalpy of activation of viscous flow ΔH* lead us to define the partial molar activation energies E a1 and E a2 for isobutyric acid and water, respectively, along with their individual separate contribution. Correlation between the two Arrhenius parameters of viscosity at all compositions shows the existence of two distinct main behaviors separated at the mole fraction in isobutyric acid equal to 0.1114. In addition, we add that correlation between Arrhenius parameters reveals the interesting Arrhenius temperature that is closely related to the vaporization temperature in the liquid–vapor equilibrium, and the limiting corresponding partial molar properties permits us to predict the boiling points of the pure components.
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viscosity Arrhenius activation energy and derived partial molar properties in isobutyric acid water binary mixtures near and far away from the critical temperature 302 15 to 313 15 k
Journal of Solution Chemistry, 2015Co-Authors: Hassen Salhi, M. Dallel, Abdullah A. Alarfaj, Noureddine Ouerfelli, Zouheir TrabelsiAbstract:Calculations of the viscosity Arrhenius activation energy and derived partial molar properties, from literature experimental values of viscosity in isobutyric acid + water binary mixtures from 302.15 to 313.15 K, are presented here. The close similarity between the values of the Arrhenius activation energy E a and the enthalpy of activation of viscous flow ΔH* lead us to define the partial molar activation energies E a1 and E a2 for isobutyric acid and water, respectively, along with their individual separate contribution. Correlation between the two Arrhenius parameters of viscosity at all compositions shows the existence of two distinct main behaviors separated at the mole fraction in isobutyric acid equal to 0.1114. In addition, we add that correlation between Arrhenius parameters reveals the interesting Arrhenius temperature that is closely related to the vaporization temperature in the liquid–vapor equilibrium, and the limiting corresponding partial molar properties permits us to predict the boiling points of the pure components.
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Viscosity Arrhenius Activation Energy and Derived Partial Molar Properties in Isobutyric Acid + Water Binary Mixtures Near and Far Away from the Critical Temperature, 302.15 to 313.15 K
Journal of Solution Chemistry, 2015Co-Authors: D. Das, Hassen Salhi, M. Dallel, Abdullah A. Al-arfaj, Zouheir Trabelsi, Noureddine OuerfelliAbstract:Calculations of the viscosity Arrhenius activation energy and derived partial molar properties, from literature experimental values of viscosity in isobutyric acid + water binary mixtures from 302.15 to 313.15 K, are presented here. The close similarity between the values of the Arrhenius activation energy E _a and the enthalpy of activation of viscous flow Δ H * lead us to define the partial molar activation energies E _a1 and E _a2 for isobutyric acid and water, respectively, along with their individual separate contribution. Correlation between the two Arrhenius parameters of viscosity at all compositions shows the existence of two distinct main behaviors separated at the mole fraction in isobutyric acid equal to 0.1114. In addition, we add that correlation between Arrhenius parameters reveals the interesting Arrhenius temperature that is closely related to the vaporization temperature in the liquid–vapor equilibrium, and the limiting corresponding partial molar properties permits us to predict the boiling points of the pure components.
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contribution to modeling the viscosity Arrhenius type equation for some solvents by statistical correlations analysis
Fluid Phase Equilibria, 2014Co-Authors: R B Hajkacem, Noureddine Ouerfelli, J V Herraez, M Guettari, H Hamda, M. DallelAbstract:Abstract Estimation and knowledge of transport properties of fluids are essential for heat and mass flow. Viscosity is one of the important properties which are affected by temperature and pressure. In the present work, based on the use of econometric and statistical techniques for parametric and non-parametric regression analysis and statistical correlation tests, we propose an equation modeling the relationship between the two parameters of viscosity Arrhenius-type equation, such as the Arrhenius energy ( E a ) or the pre-exponential factor ( A s ). In addition, we introduce a third interesting parameter called Arrhenius temperature ( T A ), to enrich the discussion. Empirical validation using 48 data set of pure solvents from the literature and studied at different temperature ranges gives excellent statistical results which allow us to redefine the Arrhenius equation using a single parameter instead of two ones. In addition, the proposed model is very useful for engineering data and permits to estimate one non-available parameter when the second one is available.
M. Dallel - One of the best experts on this subject based on the ideXlab platform.
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Viscosity Arrhenius Activation Energy and Derived Partial Molar Properties in Isobutyric Acid + Water Binary Mixtures Near and Far Away from the Critical Temperature, 302.15 to 313.15 K
Journal of Solution Chemistry, 2015Co-Authors: Hassen Salhi, M. Dallel, Abdullah A. Al-arfaj, Zouheir Trabelsi, Noureddine OuerfelliAbstract:Calculations of the viscosity Arrhenius activation energy and derived partial molar properties, from literature experimental values of viscosity in isobutyric acid + water binary mixtures from 302.15 to 313.15 K, are presented here. The close similarity between the values of the Arrhenius activation energy E a and the enthalpy of activation of viscous flow ΔH* lead us to define the partial molar activation energies E a1 and E a2 for isobutyric acid and water, respectively, along with their individual separate contribution. Correlation between the two Arrhenius parameters of viscosity at all compositions shows the existence of two distinct main behaviors separated at the mole fraction in isobutyric acid equal to 0.1114. In addition, we add that correlation between Arrhenius parameters reveals the interesting Arrhenius temperature that is closely related to the vaporization temperature in the liquid–vapor equilibrium, and the limiting corresponding partial molar properties permits us to predict the boiling points of the pure components.
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viscosity Arrhenius activation energy and derived partial molar properties in isobutyric acid water binary mixtures near and far away from the critical temperature 302 15 to 313 15 k
Journal of Solution Chemistry, 2015Co-Authors: Hassen Salhi, M. Dallel, Abdullah A. Alarfaj, Noureddine Ouerfelli, Zouheir TrabelsiAbstract:Calculations of the viscosity Arrhenius activation energy and derived partial molar properties, from literature experimental values of viscosity in isobutyric acid + water binary mixtures from 302.15 to 313.15 K, are presented here. The close similarity between the values of the Arrhenius activation energy E a and the enthalpy of activation of viscous flow ΔH* lead us to define the partial molar activation energies E a1 and E a2 for isobutyric acid and water, respectively, along with their individual separate contribution. Correlation between the two Arrhenius parameters of viscosity at all compositions shows the existence of two distinct main behaviors separated at the mole fraction in isobutyric acid equal to 0.1114. In addition, we add that correlation between Arrhenius parameters reveals the interesting Arrhenius temperature that is closely related to the vaporization temperature in the liquid–vapor equilibrium, and the limiting corresponding partial molar properties permits us to predict the boiling points of the pure components.
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Viscosity Arrhenius Activation Energy and Derived Partial Molar Properties in Isobutyric Acid + Water Binary Mixtures Near and Far Away from the Critical Temperature, 302.15 to 313.15 K
Journal of Solution Chemistry, 2015Co-Authors: D. Das, Hassen Salhi, M. Dallel, Abdullah A. Al-arfaj, Zouheir Trabelsi, Noureddine OuerfelliAbstract:Calculations of the viscosity Arrhenius activation energy and derived partial molar properties, from literature experimental values of viscosity in isobutyric acid + water binary mixtures from 302.15 to 313.15 K, are presented here. The close similarity between the values of the Arrhenius activation energy E _a and the enthalpy of activation of viscous flow Δ H * lead us to define the partial molar activation energies E _a1 and E _a2 for isobutyric acid and water, respectively, along with their individual separate contribution. Correlation between the two Arrhenius parameters of viscosity at all compositions shows the existence of two distinct main behaviors separated at the mole fraction in isobutyric acid equal to 0.1114. In addition, we add that correlation between Arrhenius parameters reveals the interesting Arrhenius temperature that is closely related to the vaporization temperature in the liquid–vapor equilibrium, and the limiting corresponding partial molar properties permits us to predict the boiling points of the pure components.
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contribution to modeling the viscosity Arrhenius type equation for some solvents by statistical correlations analysis
Fluid Phase Equilibria, 2014Co-Authors: R B Hajkacem, Noureddine Ouerfelli, J V Herraez, M Guettari, H Hamda, M. DallelAbstract:Abstract Estimation and knowledge of transport properties of fluids are essential for heat and mass flow. Viscosity is one of the important properties which are affected by temperature and pressure. In the present work, based on the use of econometric and statistical techniques for parametric and non-parametric regression analysis and statistical correlation tests, we propose an equation modeling the relationship between the two parameters of viscosity Arrhenius-type equation, such as the Arrhenius energy ( E a ) or the pre-exponential factor ( A s ). In addition, we introduce a third interesting parameter called Arrhenius temperature ( T A ), to enrich the discussion. Empirical validation using 48 data set of pure solvents from the literature and studied at different temperature ranges gives excellent statistical results which allow us to redefine the Arrhenius equation using a single parameter instead of two ones. In addition, the proposed model is very useful for engineering data and permits to estimate one non-available parameter when the second one is available.
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Viscosity Arrhenius activation energy and derived partial molar properties in methanol + N,N-dimethylacetamide binary mixtures at temperatures from 303.15 K to 318.15 K
Physics and Chemistry of Liquids, 2014Co-Authors: Hassen Salhi, M. Dallel, Zouheir Trabelsi, N.o. Alzamil, M.a. Alkhaldi, Noureddine OuerfelliAbstract:Excess properties calculated from literature values of experimental density and viscosity in N,N-dimethylacetamide + methanol binary mixtures (from 303.15 K to 318.15 K) can lead us to test different correlation equations as well as their corresponding relative functions. Inspection of the Arrhenius activation energy Ea and the enthalpy of activation of viscous flow ΔH* shows very close values, here we can define partial molar activation energy Ea1 and Ea2 for N,N-dimethylacetamide and methanol, respectively, along with their individual contribution separately. Correlation between the two Arrhenius parameters of viscosity in all compositions shows existence of main distinct behaviours separated by particular mole fractions in N,N-dimethylacetamide. In addition, we add that correlation between Arrhenius parameters reveals interesting Arrhenius temperature that is closely related to the vapourisation temperature in the liquid vapour equilibrium and the limiting corresponding partial molar properties can per...
Roger Frech - One of the best experts on this subject based on the ideXlab platform.
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Extending the compensated Arrhenius formalism to concentrated alcohol electrolytes: Arrhenius vs. non-Arrhenius behavior
Electrochimica Acta, 2011Co-Authors: Allison M. Fleshman, Matt Petrowsky, Jeremy D. Jernigen, R.s.p. Bokalawela, Matthew B. Johnson, Roger FrechAbstract:The compensated Arrhenius formalism is applied to ionic conductivities in alcohol-based electrolytes at concentrations where the salt makes a non-negligible contribution to the static dielectric constant of the solution. The temperature-dependent behavior of the conductivity depends on the amount of added salt. Non-Arrhenius behavior is observed for low to moderate salt concentrations, while Arrhenius behavior occurs at high concentrations. The compensated Arrhenius formalism provides insight into this behavior by analyzing the effect of salt concentration on the temperature dependence of the exponential prefactor. When the compensated Arrhenius prefactors are plotted against the solution static dielectric constants using the Ea obtained from the compensated Arrhenius equation, the prefactors lie on a single master curve. In contrast, a similar plot based on the Ea obtained from a simple Arrhenius plot of the same conductivity data does not yield a master curve. Application of the compensated Arrhenius formalism requires the construction of a reference curve. It is essential that the range of static dielectric constant values spanned by the reference curve encompasses the range of temperature-dependent static dielectric constant values of the selected alcohol electrolyte. This will allow an accurate interpolation to obtain the appropriate reference conductivity. A detailed description is given for the method used to construct an appropriate reference conductivity curve.
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Temperature dependence of ion transport: the compensated Arrhenius equation.
The journal of physical chemistry. B, 2009Co-Authors: Matt Petrowsky, Roger FrechAbstract:The temperature-dependent conductivity originating in a thermally activated process is often described by a simple Arrhenius expression. However, this expression provides a poor description of the data for organic liquid electrolytes and amorphous polymer electrolytes. Here, we write the temperature dependence of the conductivity as an Arrhenius expression and show that the experimentally observed non-Arrhenius behavior is due to the temperature dependence of the dielectric constant contained in the exponential prefactor. Scaling the experimentally measured conductivities to conductivities at a chosen reference temperature leads to a "compensated" Arrhenius equation that provides an excellent description of temperature-dependent conductivities. A plot of the prefactors as a function of the solvent dielectric constant results in a single master curve for each family of solvents. These data suggest that ion transport in these and related systems is governed by a single activated process differing only in the activation energy for each family of solvents. Connection is made to the shift factor used to describe electrical and mechanical relaxation in a wide range of phenomena, suggesting that this scaling procedure might have broad applications.
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temperature dependence of ion transport the compensated Arrhenius equation
Journal of Physical Chemistry B, 2009Co-Authors: Matt Petrowsky, Roger FrechAbstract:The temperature-dependent conductivity originating in a thermally activated process is often described by a simple Arrhenius expression. However, this expression provides a poor description of the data for organic liquid electrolytes and amorphous polymer electrolytes. Here, we write the temperature dependence of the conductivity as an Arrhenius expression and show that the experimentally observed non-Arrhenius behavior is due to the temperature dependence of the dielectric constant contained in the exponential prefactor. Scaling the experimentally measured conductivities to conductivities at a chosen reference temperature leads to a “compensated” Arrhenius equation that provides an excellent description of temperature-dependent conductivities. A plot of the prefactors as a function of the solvent dielectric constant results in a single master curve for each family of solvents. These data suggest that ion transport in these and related systems is governed by a single activated process differing only in th...
Micha Peleg - One of the best experts on this subject based on the ideXlab platform.
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Temperature–viscosity models reassessed
Critical Reviews in Food Science and Nutrition, 2017Co-Authors: Micha PelegAbstract:ABSTRACTThe temperature effect on viscosity of liquid and semi-liquid foods has been traditionally described by the Arrhenius equation, a few other mathematical models, and more recently by the WLF and VTF (or VFT) equations. The essence of the Arrhenius equation is that the viscosity is proportional to the absolute temperature's reciprocal and governed by a single parameter, namely the energy of activation. However, if the absolute temperature in °K in the Arrhenius equation is replaced by T + b where both T and the adjustable b are in°C units, the result is a two-parameters model, which has superior fit to experimental viscosity-temperature data. This modified version of the Arrhenius equation is also mathematically equal to the WLF and VTF equations, which are known to be equal to each other. Thus despite their dissimilar appearances all three equations are essentially the same model, and when used to fit experimental temperature-viscosity data render exactly the same very high regression coefficient. ...
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the Arrhenius equation revisited
Critical Reviews in Food Science and Nutrition, 2012Co-Authors: Micha Peleg, Mark D. Normand, Maria Grazia CorradiniAbstract:The Arrhenius equation has been widely used as a model of the temperature effect on the rate of chemical reactions and biological processes in foods. Since the model requires that the rate increase monotonically with temperature, its applicability to enzymatic reactions and microbial growth, which have optimal temperature, is obviously limited. This is also true for microbial inactivation and chemical reactions that only start at an elevated temperature, and for complex processes and reactions that do not follow fixed order kinetics, that is, where the isothermal rate constant, however defined, is a function of both temperature and time. The linearity of the Arrhenius plot, that is, Ln[k(T)] vs. 1/T where T is in °K has been traditionally considered evidence of the model's validity. Consequently, the slope of the plot has been used to calculate the reaction or processes’ “energy of activation,” usually without independent verification. Many experimental and simulated rate constant vs. temperature relation...
Wolfgang Schuhmann - One of the best experts on this subject based on the ideXlab platform.
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on the theory of electrolytic dissociation the greenhouse effect and activation energy in electro catalysis a tribute to svante augustus Arrhenius
Chemistry: A European Journal, 2019Co-Authors: Justus Masa, Stefan Barwe, Corina Andronescu, Wolfgang SchuhmannAbstract:: Svante Augustus Arrhenius (1859, Vik - 1927, Stockholm) received the Nobel Prize for Chemistry in 1903 "in recognition of the extraordinary services he rendered to the advancement of chemistry by his electrolytic theory of dissociation". Arrhenius was a physicist, and he received his PhD from the University of Uppsala, where he later became a professor for phyiscal chemistry, the first in the country for this subject. He was offered several positions as professor abroad, but decided to remain in Sweden and to build a Nobel Institute for physical chemistry using the Nobel funds. He remained director of the Institute until his death. There are powerful lessons to take from Svante August Arrhenius' journey leading to a Nobel laureate as there are from his tremendous contributions to chemistry and science in general, including climate science, immunochemistry and cosmology. The theory of electrolytic dissociation for which Arrhenius received the 1903 Nobel Prize in Chemistry has had a profound impact on our understanding of the chemistry of solutions, chemical reactivity, mechanisms underlying chemical transformations as well as physiological processes. As a tribute to Arrhenius, we present a brief historical perspective and present status of the theory of electrolytic dissociation, its relevance and role to the development of electrochemistry, as well as some perspectives on the possible role of the theory to future advancements in electroanalysis, electrocatalysis and electrochemical energy storage. The review briefly highlights Arrhenius' contribution to climate science owing to his studies on the potential effects of increased anthropogenic CO2 emissions on the global climate. These studies were far ahead of their time and revealed a daunting global dilemma, global warming, that we are faced with today. Efforts to abate or reverse CO2 accumulation constitute one of the most pressing scientific problems of our time, "man's urgent strive to save self from the adverse effects of his self-orchestrated change on the climate". Finally, we review the application of the Arrhenius equation that correlates reaction rate constants (k) and temperature (T); k=Ae(-Ea/RT) , in determining reaction barriers in catalysis with a particular focus on recent modifications of the equation to account for reactions exhibiting non-linear Arrhenius behavior with concave curvature due to prevalence of quantum mechanical tunneling, as well as infrequent convexity of Arrhenius plots due to decrease of the microcanonical rate coefficient with energy as observed for some enzyme catalyzed reactions.