Simple Neutron-Transfer Model for the Exchange Resonance inHe3-He4Elastic Scattering

<div>A linear free energy model is presented that predicts the second order rate constant for the abiotic reduction of nitroaromatic compounds (NACs). For this situation previously presented models use the one electron reduction potential of the NAC reaction. If such value is not available, it has been has been proposed that it could be computed directly or estimated from the electron affinity (EA). The model proposed herein uses the Gibbs free energy of the hydrogen atom transfer (HAT) as the parameter in the linear free energy model. Both models employ quantum chemical computations for the required thermodynamic parameters. The available and proposed models are compared using second order rate constants obtained from five investigations reported in the literature in which a variety of NACs were exposed to a variety of reductants. A comprehensive analysis utilizing all the NACs and reductants demonstrate that the computed hydrogen atom transfer model and the experimental one electron reduction potential model have similar root mean square errors and residual error probability distributions. In contrast, the model using the computed electron affinity has a more variable residual error distribution with a significant number of outliers. The results suggest that a linear free energy model utilizing computed hydrogen transfer reaction free energy produces a more reliable prediction of the NAC abiotic reduction second order rate constant than previously available methods. The advantages of the proposed hydrogen atom transfer model and its mechanistic implications are discussed as well.</div>

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Modelling and Validation of two Heat and Mass Transfer Model of Living Walls and Evaluation of Their Impact on the Energy Performance of a Supermarket in a Semiarid Climate

Proceedings of Building Simulation 2019: 16th Conference of IBPSA ◽

10.26868/25222708.2019.211051 ◽

2020 ◽

Author(s):

Mauricio García ◽

Sergio Vera ◽

Fabien Roualt ◽

Waldo Bustamante

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Energy Performance ◽

Transfer Model ◽

Mass Transfer Model ◽

Semiarid Climate

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Theoretical Post-Dryout Heat Transfer Model

International Journal of Computational Physics Series ◽

10.29167/a1i1p142-150 ◽

2018 ◽

Vol 1 (1) ◽

pp. 142-150

Author(s):

Murat Tunc ◽

Ayse Nur Esen ◽

Doruk Sen ◽

Ahmet Karakas

Keyword(s):

Heat Transfer ◽

Droplet Diameter ◽

Heat Transfer Model ◽

Transfer Model ◽

Operating Pressure ◽

Vertical Pipe ◽

Two Phase ◽

Experimental Values ◽

Reactor Operating ◽

Coolant System

A theoretical post-dryout heat transfer model is developed for two-phase dispersed flow, one-dimensional vertical pipe in a post-CHF regime. Because of the presence of average droplet diameter lower bound in a two-phase sparse flow. Droplet diameter is also calculated. Obtained results are compared with experimental values. Experimental data is used two-phase flow steam-water in VVER-1200, reactor coolant system, reactor operating pressure is 16.2 MPa. On heater rod surface, dryout was detected as a result of jumping increase of the heater rod surface temperature. Results obtained display lower droplet dimensions than the experimentally obtained values.

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