Abstract: In order to predict hot deformation behavior of superalloy nimonic 80A, a back-propagational artificial neural network (BP-ANN) and strain-dependent Arrhenius-type model were established based on the experimental data from isothermal compression tests on a Gleeble-3500 thermo-mechanical simulator at temperatures ranging of 1050–1250 ̋C, strain rates ranging of 0.01–10.0 s ́1. A comparis...

Molecular dynamics simulations have been used extensively to model the folding and unfolding of proteins. The rates of folding and unfolding should follow the Arrhenius equation over a limited range of temperatures. This study shows that molecular dynamic simulations of the unfolding of crambin between 500K and 560K do follow the Arrhenius equation. They also show that while there is a large am...

The validity of the Arrhenius equation for dissociative electron attachment rate coefficients is investigated. A general analysis allows us to obtain estimates of the upper temperature bound for the range of validity of the Arrhenius equation in the endothermic case and both lower and upper bounds in the exothermic case with a reaction barrier. The results of the general discussion are illustra...

Modeling the flow curves of materials at elevated temperatures is the first step in mathematical simulation of the hot deformation processes of them. In this work a comparative study was provided to examine the capability of three different constitutive equations in modeling the hot deformation flow curves of AZ91 magnesium alloy. For this, the Arrhenius equation with strain dependent constants...

In this work, kinetics and thermodynamics of esterification reaction were studied. This research investigated the esterification reaction between methanol and acidified oil catalyzed by sulfonated cation exchange resin and proposed a new rate equation for consideration of kinetics of this reaction according to the Langmuir-Hinshelwood mechanism. Thermodynamics and kinetics parameters were calcu...

The viscosity of glass is the most important technological property to manufactures and various applications. Practically, finding an accurate equation express behavior in entire transition temperature range tremendously challenge because it spans more than ten orders magnitude. After a brief review existing empirical equations, this work focuses on correlating silica with evolution medium-rang...

The catalytic activity and activation energy of an enzyme are obtained by measuring the rate of the enzymic reaction at two different temperatures. With the aid of the Arrhenius equation, these two parameters can be used to calculate a value proportional to the quantity of enzyme. Using this approach to investigate the isoenzymes of creatine kinase, it was shown that the activation energy incre...