Kinetics of nitro-nitrito linkage isomerization [Co(NH3)5NO2]X2 ⇌' [Co(NH3)5ONO]X2 (X=Cl−, Br−, NO3−) in the solid state. Computer simulation and experimental results

An algorithm was developed for the simulation of a phase transition in solid state whichmakes it possible to obtain the kinetic curves of transformation under different initialconditions (the number and arrangement of new phase nuclei, the distance betweenthe nearest nuclei). The simulation results were analyzed using the Kolmogorov-Johnson-Mehl-Avrami equation and the corresponding coefficients were determined.The correlation between the simulation results and the experimental kinetics of theaustenite isothermal transformation in alloyed steels was shown.

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Computer simulation of metal co-doping in lithium niobate

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2014.0406 ◽

2014 ◽

Vol 470 (2171) ◽

pp. 20140406 ◽

Cited By ~ 5

Author(s):

Romel M. Araujo ◽

Mário E. G. Valerio ◽

Robert A. Jackson

Keyword(s):

Computer Simulation ◽

Solid State ◽

Lithium Niobate ◽

Computer Modelling ◽

Defect Chemistry ◽

Experimental Results ◽

Solid State Reactions ◽

Co Doping ◽

Nonlinear Properties ◽

Electro Optic

Lithium niobate, LiNbO 3 , is an important technological material with good electro-optic, acousto-optic, elasto-optic, piezoelectric and nonlinear properties. Computer modelling provides a useful means of determining the properties of the material, including its defect chemistry, and the effect of doping on the structure. In this work, double-doped LiNbO 3 was studied, and the energetics of the solid-state reactions leading to incorporation of the dopants was calculated. The following combinations of dopants were studied: Fe and Cu; Ce and Cu; Ce and Mn; Fe and Rh; and Ru and Fe. For most of these combinations, the co-doping process decreases the energy required for incorporation of the dopants, and the final defect configurations are consistent with experimental results, where available.

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Kinetic Features of Solid-State Reactive Diffusion between Au and Sn-Base Solder

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.2473 ◽

2007 ◽

Vol 539-543 ◽

pp. 2473-2478 ◽

Cited By ~ 16

Author(s):

M. Kajihara ◽

T. Takenaka

Keyword(s):

Solid State ◽

Diffusion Couple ◽

Diffusion Bonding ◽

Experimental Results ◽

Reactive Diffusion ◽

Diffusion Couples ◽

Kinetics Of ◽

Bonding Technique ◽

Kinetic Features

The kinetics of the solid-state reactive diffusion between Au and Sn was experimentally observed using Sn/Au/Sn diffusion couples prepared by a diffusion bonding technique. The diffusion couples were isothermally annealed at a temperature of T = 453 K. Due to annealing, AuSn, AuSn2 and AuSn4 compound layers are formed at the interface in the diffusion couple. The experimental results were used to evaluate quantitatively the effect of Ni on the growth of the Au–Sn compounds. The evaluation indicates that the addition of Ni into Sn between 1 and 5 mass% accelerates the growth of the Au–Sn compounds at T = 433–473 K.

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Kinetics of ethane oxidation in a high pressure jet-stirred reactor : experimental results

Journal de Chimie Physique ◽

10.1051/jcp/1990871173 ◽

1990 ◽

Vol 87 ◽

pp. 1173-1185 ◽

Cited By ~ 3

Author(s):

P Dagaut ◽

M Cathonnet

Keyword(s):

High Pressure ◽

Experimental Results ◽

Ethane Oxidation ◽

Stirred Reactor ◽

Kinetics Of

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Submerged upflow biotower operation and computer simulation

Water Science & Technology ◽

10.2166/wst.1994.0554 ◽

1994 ◽

Vol 30 (11) ◽

pp. 143-146

Author(s):

Ronald D. Neufeld ◽

Christopher A. Badali ◽

Dennis Powers ◽

Christopher Carson

Keyword(s):

Computer Simulation ◽

Benzoic Acid ◽

Computer Model ◽

Rate Constants ◽

Batch Mode ◽

Operational Conditions ◽

First Order ◽

Low Concentrations ◽

Biological Transformation ◽

Kinetics Of

A two step operation is proposed for the biodegradation of low concentrations (< 10 mg/L) of BETX substances in an up flow submerged biotower configuration. Step 1 involves growth of a lush biofilm using benzoic acid in a batch mode. Step 2 involves a longer term biological transformation of BETX. Kinetics of biotransformations are modeled using first order assumptions, with rate constants being a function of benzoic acid dosages used in Step 1. A calibrated computer model is developed and presented to predict the degree of transformation and biomass level throughout the tower under a variety of inlet and design operational conditions.

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LED Display Image Correction Based on Computer Simulation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.182-183.1751 ◽

2012 ◽

Vol 182-183 ◽

pp. 1751-1755

Author(s):

Xi Feng Zheng ◽

Feng Chang

Keyword(s):

Computer Simulation ◽

Correction Method ◽

Experimental Results ◽

Image Correction ◽

The Third

For the purposes of correcting the LED display image, a method based on computer simulation is proposed. First, the development of the LED display panel is introduced. Second, analyze the causes of the problem which image in LED display panel has serious high non-uniformity, and introduce the existed correction techniques which are used to reduce the non-uniformity of LED display image. Simultaneously, point out the ground for shortcomings of these techniques. Third, describe the principle of correction method based on computer simulation detail from two steps, which are the luminous collection and luminous copulation. Forth, describe the realization steps of this method in accordance with the third step. Finally, this method is supplied in a LED display panel, whose resolution is 640×480. Experimental results show that this method is able to reduce the non-uniformity of images from 11.06% to 0.98%..

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Solid-State Redox Kinetics of CeO2 in Two-Step Solar CH4 Partial Oxidation and Thermochemical CO2 Conversion

Catalysts ◽

10.3390/catal11060723 ◽

2021 ◽

Vol 11 (6) ◽

pp. 723

Author(s):

Mahesh Muraleedharan Nair ◽

Stéphane Abanades

Keyword(s):

Solid State ◽

Solar Energy ◽

Kinetic Models ◽

Oxygen Carrier ◽

Co2 Conversion ◽

Oxidation Reactions ◽

Redox Kinetics ◽

Concentrated Solar Energy ◽

Ceria Reduction ◽

Kinetics Of

The CeO2/CeO2−δ redox system occupies a unique position as an oxygen carrier in chemical looping processes for producing solar fuels, using concentrated solar energy. The two-step thermochemical ceria-based cycle for the production of synthesis gas from methane and solar energy, followed by CO2 splitting, was considered in this work. This topic concerns one of the emerging and most promising processes for the recycling and valorization of anthropogenic greenhouse gas emissions. The development of redox-active catalysts with enhanced efficiency for solar thermochemical fuel production and CO2 conversion is a highly demanding and challenging topic. The determination of redox reaction kinetics is crucial for process design and optimization. In this study, the solid-state redox kinetics of CeO2 in the two-step process with CH4 as the reducing agent and CO2 as the oxidizing agent was investigated in an original prototype solar thermogravimetric reactor equipped with a parabolic dish solar concentrator. In particular, the ceria reduction and re-oxidation reactions were carried out under isothermal conditions. Several solid-state kinetic models based on reaction order, nucleation, shrinking core, and diffusion were utilized for deducing the reaction mechanisms. It was observed that both ceria reduction with CH4 and re-oxidation with CO2 were best represented by a 2D nucleation and nuclei growth model under the applied conditions. The kinetic models exhibiting the best agreement with the experimental reaction data were used to estimate the kinetic parameters. The values of apparent activation energies (~80 kJ·mol−1 for reduction and ~10 kJ·mol−1 for re-oxidation) and pre-exponential factors (~2–9 s−1 for reduction and ~123–253 s−1 for re-oxidation) were obtained from the Arrhenius plots.

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