Kinetics of contracting geometry-type reactions in the solid state: implications from the thermally induced transformation processes of α-oxalic acid dihydrate

2020 ◽  
Vol 22 (35) ◽  
pp. 19560-19572
Author(s):  
Satoki Kodani ◽  
Nobuyoshi Koga
Keyword(s):  
Solid State ◽  
Oxalic Acid ◽  
Current Status ◽  
Thermally Induced ◽  
Oxalic Acid Dihydrate ◽  
Kinetics Of ◽  
Transformation Processes

Thermally induced transformation processes of α-oxalic acid dihydrate reveal the current status of kinetic understanding.

White Beam Synchrotron Topographic Studies of the Effects of Localized Stress Fields on the Kinetics of Single Crystal Solid State Reactions.

1988 ◽  
Vol 143 ◽  
Author(s):  
Michael Dudley
Keyword(s):  
Solid State ◽  
Reaction Kinetics ◽  
Local Reaction ◽  
Stress Fields ◽  
Solid State Reactions ◽  
Thermally Induced ◽  
White Beam ◽  
Kinetics Of ◽  
Good Agreement

AbstractWhite Beam Synchrotron Topography has been used to determine the role of localized stress fields in the solid state polymerization of single crystals of the diacetylene PTS. Results indicate that the stress fields due to grown in dislocations can accelerate local reaction kinetics in thermally induced polymerization reactions, although no such effects were previously observable in photolytically or radiolytically induced reactions. Results are analyzed in an analogous fashion to the treatment of the nucleation of solid state phase transformations at dislocations. Good agreement was found between approximate theoretical treatments and experimental observation. The response of the monomer crystal to the inhomogeneous stresses generated as a result of inhomogeneous reaction and the implications regarding local reaction kinetics are discussed in detail.

scholarly journals Mechanical properties of anhydrous oxalic acid and oxalic acid dihydrate

2019 ◽  
Vol 21 (5) ◽  
pp. 2673-2690 ◽  
Author(s):  
Francisco Colmenero
Keyword(s):  
Mechanical Properties ◽  
Density Functional Theory ◽  
Solid State ◽  
Oxalic Acid ◽  
Density Functional ◽  
Plane Waves ◽  
Functional Theory ◽  
Oxalic Acid Dihydrate ◽  
Polymorphic Forms

The mechanical properties of oxalic acid dihydrate and anhydrous oxalic acid (α and β polymorphic forms) were obtained by using rigorous theoretical solid-state methods based on density functional theory using plane waves and pseudopotentials.

Current Status of Solid-State X-Ray Systems

1985 ◽  
Vol 43 ◽  
pp. 158-161
Author(s):  
Martin Peckerar ◽  
Anastasios Tousimis
Keyword(s):  
Solid State ◽  
Electric Fields ◽  
Spectral Lines ◽  
Current Status ◽  
Mobile Charge ◽  
Electron Hole ◽  
X Ray ◽  
Sensing Systems ◽  
Transmission Electron ◽  
Electron Microscopes

Solid state x-ray sensing systems have been used for many years in conjunction with scanning and transmission electron microscopes. Such systems conveniently provide users with elemental area maps and quantitative chemical analyses of samples. Improvements on these tools are currently sought in the following areas: sensitivity at longer and shorter x-ray wavelengths and minimization of noise-broadening of spectral lines. In this paper, we review basic limitations and recent advances in each of these areas. Throughout the review, we emphasize the systems nature of the problem. That is. limitations exist not only in the sensor elements but also in the preamplifier/amplifier chain and in the interfaces between these components.Solid state x-ray sensors usually function by way of incident photons creating electron-hole pairs in semiconductor material. This radiation-produced mobile charge is swept into external circuitry by electric fields in the semiconductor bulk.

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

Catalysts ◽  
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.

Effect of praseodymium on the solid-state oxidation kinetics of an AMg2 alloy

2015 ◽  
Vol 2015 (7) ◽  
pp. 521-524 ◽  
Author(s):  
N. F. Ibrokhimov ◽  
I. N. Ganiev ◽  
A. E. Berdiev ◽  
N. I. Ganieva
Keyword(s):  
Solid State ◽  
Oxidation Kinetics ◽  
Kinetics Of

Solid-state dynamics and single-crystal to single-crystal structural transformations in octakis(3-chloropropyl)octasilsesquioxane and octavinyloctasilsesquioxane

2017 ◽  
Vol 19 (40) ◽  
pp. 27516-27529 ◽  
Author(s):  
A. Kowalewska ◽  
M. Nowacka ◽  
M. Włodarska ◽  
B. Zgardzińska ◽  
R. Zaleski ◽  
...  
Keyword(s):  
Solid State ◽  
Single Crystal ◽  
Structural Transformations ◽  
Crystal Lattices ◽  
Thermally Induced ◽  
Crystal Structural

Thermally induced formation of symmetric crystal lattices in functional POSS proceeds via different mechanisms and results in unique reversible phenomena.

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