Critical Value Estimate of Corn Moisture Diffusion Activation Energy Based on the Temperature and Humidity Monitoring

2015 ◽  
Author(s):  
Chen Siyu ◽  
Wu Wenfu ◽  
Liu Chunshan
Keyword(s):  
Activation Energy ◽  
Moisture Diffusion ◽  
Critical Value ◽  
Diffusion Activation Energy ◽  
Temperature And Humidity ◽  
Diffusion Activation ◽  
Humidity Monitoring

scholarly journals Thermally stimulated oxygen desorption in Sr2FeMoO6-δ

2018 ◽  
Vol 4 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Nikolay A. Kalanda
Keyword(s):  
Activation Energy ◽  
Oxygen Diffusion ◽  
Gas Flow ◽  
Oxygen Vacancies ◽  
Early Stage ◽  
Diffusion Activation Energy ◽  
Energy Calculation ◽  
Heating Rates ◽  
Oxygen Desorption ◽  
Diffusion Activation

Polycrystalline Sr2FeMoO6-δ specimens have been obtained by solid state synthesis from partially reduced SrFeO2,52 and SrMoO4 precursors. It has been shown that during oxygen desorption from the Sr2FeMoO6-δ compound in polythermal mode in a 5%H2/Ar gas flow at different heating rates, the oxygen index 6-δ depends on the heating rate and does not achieve saturation at T = 1420 K. Oxygen diffusion activation energy calculation using the Merzhanov method has shown that at an early stage of oxygen desorption from the Sr2FeMoO6-δ compound the oxygen diffusion activation energy is the lowest Еа = 76.7 kJ/mole at δ = 0.005. With an increase in the concentration of oxygen vacancies, the oxygen diffusion activation energy grows to Еа = 156.3 kJ/mole at δ = 0.06. It has been found that the dδ/dt = f (Т) and dδ/dt = f (δ) functions have a typical break which allows one to divide oxygen desorption in two process stages. It is hypothesized that an increase in the concentration of oxygen vacancies Vo•• leads to their mutual interaction followed by ordering in the Fe/Mo-01 crystallographic planes with the formation of various types of associations.

Hydrogen Diffusion in Boron Doped Diamond: Evidence of Hydrogen-Boron Interactions

1998 ◽  
Vol 510 ◽  
Author(s):  
J. Chevallier ◽  
B. Theys ◽  
C. Grattepain ◽  
A. Deneuville ◽  
E. Gheeraert
Keyword(s):  
Activation Energy ◽  
Boron Concentration ◽  
Hydrogen Diffusion ◽  
Diffusion Activation Energy ◽  
Boron Doped Diamond ◽  
Boron Doped ◽  
Hydrogen Ionization ◽  
Diffusion Temperature ◽  
And Diffusion ◽  
Diffusion Activation

AbstractDeuterium diffusion has been investigated in boron doped diamond as a function of the diffusion temperature and the boron concentration. The results show that, up to 480°C, hydrogen diffusion is limited by the boron concentration with a diffusion activation energy of 0.35 eV for [B] = 5×1019 cm−3. This first experimental evidence of deuterium-boron interactions in diamond is interpreted as the result of hydrogen ionization and diffusion of fairly mobile protons which form pairs with negatively charged boron acceptors

Diffusion Behavior of Carbon Atoms in Austenite Region of SCM435 Steel

2016 ◽  
Vol 850 ◽  
pp. 266-270 ◽  
Author(s):  
Dong Xu ◽  
Bing Zheng ◽  
Xing Liang Gao ◽  
Miao Yong Zhu
Keyword(s):  
Activation Energy ◽  
Diffusion Coefficient ◽  
Arrhenius Equation ◽  
Diffusion Constant ◽  
Carbon Diffusion ◽  
Diffusion Activation Energy ◽  
Diffusion Behavior ◽  
Scm435 Steel ◽  
The Relationship ◽  
Diffusion Activation

The research on the decarbonizing behavior of the austenite region of SCM435 steel was carried out. And the experimental results shewed that the relationship between the diffusion coefficient and temperature totally agreed with the Arrhenius equation and that the diffusion constant and the diffusion activation energy were uniform within the temperature range of 900-1100°C. However, when the austenite reached certain temperature, the carbon diffusion coefficient decreased significantly as temperature increased and its relationship with temperature no longer agreed with the Arrhenius equation.

scholarly journals DEPENDENCE ACTIVATION ENERGY OF THE ELECTROREDUCTION OF PALLADIUM(II) BIS-HYDROXYETHYLIMINODIACETATE COMPLEXES ON THE OVERPOTENTIAL

2019 ◽  
Vol 85 (1) ◽  
pp. 32-37
Author(s):  
Valeriy Kublanovskii ◽  
Vasyl Nikitenko
Keyword(s):  
Activation Energy ◽  
Kinetic Method ◽  
Free Ligand ◽  
Energy Transition ◽  
Electrode Process ◽  
Diffusion Current ◽  
Diffusion Activation Energy ◽  
Transfer Coefficients ◽  
Transition Reaction ◽  
Diffusion Activation

The kinetic (exchange currents, apparent elect-ron transfer coefficients) and energetic (activation energies of diffusion and electron-transfer reaction) parameters of electroreduction of palladium (II) bis-hydroxyethyliminodiacetate complexes from an ele-ctrolyte containing an excess of free ligand have been determined. A method is proposed for calculating the actual activation energy of the electrode process that is controlled by mixed kinetics, based on the dif-fusion activation energy, transition reaction and the ratio of surface and volume concentrations of potenti-al-determining ions in the solution under study or the ratio of the limiting diffusion current jd and dischar-ge current jk of palladium (II) hydroxyethyliminodi-   acetate complexes. The actual activation energy Af of the electrode process, which is controlled by mixed kinetics, is calculated based on the diffusion activati-on energy, transition reaction and the ratio of the li-miting diffusion current jd and discharge current jk of palladium (II) bis-hydroxyethyliminodiacetate com-plexes. The contribution of the activation energy of the transition stage (slow discharge) and the diffusion activation energy of bis -hydroxyethyliminodiacetate palladium (II) complexes to the actual activation ener-gy of the electrode process limited by mixed kine-tics is determined. The dependence of actual activation energy on electrode process overpotential has been stu-died. The actual activation energy Af of the electro-de process varies from the value of the activation ener-gy of the transition reaction At (63.4 kJ×mol–1) to the value of the diffusion activation energy Ad (22.5 kJ ×mol–1). The activation energy calculated according to Tyomkin can be considered as the actual activation energy Af of the discharge stage at a given polarizati-on DE only with a purely kinetic control of the pro-cess rate. The activation energy experimentally deter-mined by the temperature-kinetic method according to the Arrhenius equation and calculated by the pro-posed method is the actual activation energy Af of the electrode process, controlled by mixed kinetics. There is a coincidence of the experimentally determi-ned by the Gorbachev method and the actual Af acti-vation energy of electrode process controlled by mi-xed kinetics calculated by the proposed method. A good agreement between the calculated and experi-mentally determined values of the actual activation energy of the electrode process is observed.

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