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Showing 1 to 20 of 259 for “"ARRHENIUS"”.
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Investigation of the non-Arrhenius behavior of fast ion conducting glasses
<p>Traditional glassy ion conductors exhibit Arrhenius temperature dependence of the d.c. conductivity. Recently, Kinc and Martin1 reported the discovery of a Fast Ion Conducting (FIC) glass with ionic conductivities as high as 10-2 (O-cm)-1. Surprisingly, while this is a very high conductivity for …
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Study of atomic scale dynamics of glass-forming metallic liquids using neutron scattering experiments and molecular dynamics simulations
… molecular liquids. Dynamical crossover from Arrhenius to super-Arrhenius behavior is also observed in other transport properties (self diffusion coefficient, self relaxation time, and shear viscosity) in computer simulations, consistent with experimental observations. A non-parametric, …
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A Direct Determination of the Activation Energy for the Reaction of Nitric Oxide With Ozone
A conventional Arrhenius fit to the data is
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Metastability of Magnetic Nanoparticles in Magnetization Relaxation with Different Dynamics and Distributions of Magnetic Anisotropy
… of the metastable state follows a modified-Arrhenius law where the energy barrier has a dependency on temperature and standard deviation of the distributions in addition to magnetic field and magnetic anisotropy. The magnetic anisotropy barrier is determined by the smallest particle within a …
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Modeling The Fluid To Solid Transition In Cement Paste, Mortar, And Concrete
… of high concrete temperature by using five Arrhenius-type equations that can represent nonlinearity in Arrhenius plot. In addition, the growth model was applied to represent setting behaviors of paste, mortar, and concrete, and the quantitative characterization of the setting behaviors is …
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Relaxation dynamics in heme proteins
… by (i) nonexponential time dependence and non-Arrhenius temperature dependence (FIM1(v), FIM1(r)); (ii) exponential time dependence and non-Arrhenius temperature dependence (FIMO(Ai ___. Aj)); exponential time dependence and Arrhenius temperature dependence (FIMX(v)). The influence of pH is …
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Temperature dependence of plant photosynthesis and respiration using the Macromolecular Rate Theory (MMRT)
… constant-Q10 relationships, simple and peaked Arrhenius formulations, and macro molecular rate theory (MMRT), with and without an explicit high temperature deactivation term. Γ* increased approximately exponentially across the measurement range from 4 to 42 °C, and a constant-Q10 model best …
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Lewis Base Catalyzed Enantioselective Aldol Additions: Preparative and Mechanistic Studies
… one or two phosphoramides. Determination of Arrhenius activation parameters revealed that aldol addition occurs through the reversible albeit unfavorable formation of an activated complex. Finally, natural abundance 13C NMR kinetic isotope effect (KIE) studies have determined aldolization to …
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Conformational relaxation in heme proteins: Ligand rebinding above the glass transition
… is nonexponential in time and does not obey an Arrhenius relation. The extent of the enthalpic shift is consistent with a prediction based upon the inhomogeneous rebinding of band III, the charge transfer band observed in unligated Mb near 13100 cm$\sp{-1}$. Geminate rebinding from 160 to 290 K …
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Heat transfer model for the ignition of metal powder on a heated filament
… are derived for one dimensional heat flow. An Arrhenius type expression is used to describe the chemical reaction leading to ignition with the pre-exponent as an adjustable parameter. The contact resistance between each powder layer was derived using the bulk thermal properties of the powder. …
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Long jumps in surface diffusion on tungsten(211)
… deduce the jump length from the prefactor in the Arrhenius plot, but this is quite an uncertain procedure. To establish the possible contribution of long jumps in atomic migration, observations have been made in a field ion microscope of single adatoms on W(211), where diffusion is …
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Temperature-Dependent Fracture Toughness Evaluation of WC-10Co4Cr Coating/1018 Low Carbon Steel Substrate System
… two types of models developed in terms of the Arrhenius type equation and rate controlling theory, utilizing indentation test data, in this research. One is based on the crystal structures of individual phases in the composite coating, the other considers the microcrack formation in the …
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Low Temperature Electron Irradiation Induced Defects in Gallium-Arsenide: Bulk and Surface Acoustic Wave Studies
… reorientation kinetics of both peaks follow the Arrhenius law.
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Kinetic Studies of Hydroxyl and Hydrogen Atom Reactions
… the reaction shows significant curvature in the Arrhenius plot. The LP-RF technique was also used to measure the rate constant of the H + CH3Br reaction over the temperature range 400-813 K. TST and density functional theory (DFT) calculations show that the dominant reaction channel is …
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Understanding Allosteric Arginine Mutations Using Macromolecular Rate Theory
… rates have been traditionally modelled with the Arrhenius and Eyring-Polanyi equations. These models assume that the reaction rate is exponential with temperature, and thus the natural log of the reaction rate versus 1/T is linear. Significant deviations from these models at high temperatures has …
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Low Temperature Electrical Transport in 2D Layers of Graphene, Graphitic Carbon Nitride, Graphene Oxide and Boron-Nitrogen-Carbon
… in these samples was governed by two different Arrhenius behaviors in the studied temperature range. In the case of rGO and BNC layers, electrical conduction show two different transport mechanisms in two different temperature regimes. At higher temperatures, Arrhenius-like temperature …
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Diffusion of iron and cobalt in nickel single crystals
… temperature dependence can be represented by an Arrhenius type relationship,...The effect of the isotopic mass on the diffusion coefficient of cobalt in nickel has also been investigated. The isotope effect parameter, E, was found to vary from .26 to .84 over the temperature range 970.5°C to …
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Microstructure Control and Crystallization Kinetics in Amorphous Cadmium-Germanium - Arsenide (Devitrification, Differential Scanning, Calorimetry)
… of crystallization, modeling to the Avrami and Arrhenius equations; and techniques for optimization of quantitative data from these devices is discussed for both heating rate and isothermal crystallization.
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Mathematical modelling of flow and combustion in internal combustion engines
… combustion models (the eddy-break-up and the Arrhenius models) and proposes a new formulation of a flame-front model. Calculations have been performed for a one-dimensional test case and for a representative spark-ignition engine in order to determine the grid and time step requirements for …
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