Which Activation Energy Do We Measure? Analysis of the Kinetics of Propene-3-13C Double-Bond-Shift Reaction on Silicalite-1 by1H MAS NMR In Situ

2018 ◽  
Vol 122 (41) ◽  
pp. 23432-23440 ◽  
Author(s):  
Sergei S. Arzumanov ◽  
Alexander G. Stepanov
Keyword(s):  
Activation Energy ◽  
Double Bond ◽  
Mas Nmr ◽  
Measure Analysis ◽  
Shift Reaction ◽  
Kinetics Of ◽  
Double Bond Shift

Kinetics of Pt Silicide Formation Studied by Spectral Ellipsometry

1997 ◽  
Vol 470 ◽  
Author(s):  
R. Schwarz ◽  
A. Dittrich ◽  
S. M. Zhou ◽  
M. Hundhausen ◽  
L. Ley ◽  
...  
Keyword(s):  
Activation Energy ◽  
Crystalline Silicon ◽  
Silicon Substrates ◽  
Silicide Formation ◽  
Spectral Ellipsometry ◽  
Step Process ◽  
Depth Profiles ◽  
Ellipsometric Angle ◽  
Kinetics Of

ABSTRACTSuicide formation during thermal annealing of thin Pt layers deposited by evaporation onto crystalline silicon substrates was studied by in-situ spectral ellipsometry. As was shown in an earlier study, Pt suicide is formed in a two-step process with intermediate stages of Pt2Si and PtSi at temperatures of about 190 and 240 °C, respectively. We observed a shift of about 15 °C of the di- and monosilicide formation, when the anneal rate was lowered from 3 to 1 K/min. The analysis of the reaction kinetics using the normalized ellipsometric angle δ yields a good fit to the data for different anneal rates with an activation energy of (1.6 ± 0.2) eV. The underlying model of suicide formation through a multilayer system was checked with depth profiles and compositional information obtained from Rutherford Backscattering.

Nitridation Isothermal Kinetics of In Situ β-Sialon Bonded Al2O3-C Refractories

2016 ◽  
Vol 697 ◽  
pp. 572-575
Author(s):  
Xue Qing Yang ◽  
Nai Peng ◽  
Cheng Ji Deng
Keyword(s):  
Activation Energy ◽  
Apparent Activation Energy ◽  
Isothermal Kinetics ◽  
Nitridation Reaction ◽  
Result Show ◽  
Different Temperatures ◽  
Two Stages ◽  
Kinetics Of ◽  
And Diffusion

The kinetics of in-situ β- Sialon bonded Al2O3-C (SAC) refractories were investigated by TGA techniques via isothermal nitridation experiments at different temperatures. The result show that the nitridation process of in-situ β-Sialon bonded Al2O3-C refractories can be divided into two stages: the nitridation reaction rate controlling stage in the first 10 min, and the apparent activation energy of nitridation reaction is 370 kJ/mol ; then the reaction is controlled by both chemical reaction and diffusion rate in the following 110 min, the apparent activation energy of nitridation reaction is 410 kJ/mol.

Alkali activation of reactive silicas in cements: in situ 29Si MAS NMR studies of the kinetics of silicate polymerization

1996 ◽  
Vol 31 (13) ◽  
pp. 3365-3373 ◽  
Author(s):  
A. R. Brough ◽  
C. M. Dobson ◽  
I. G. Richardson ◽  
G. W. Groves
Keyword(s):  
Mas Nmr ◽  
Alkali Activation ◽  
29Si Mas Nmr ◽  
Nmr Studies ◽  
Kinetics Of

Structural Re-Organization Kinetics of Nanocrystalline Pt Films during In Situ Annealing

2012 ◽  
Vol 323-325 ◽  
pp. 149-154 ◽  
Author(s):  
Wolfgang Gruber ◽  
Sujoy Chakravarty ◽  
Carsten Baehtz ◽  
Harald Schmidt
Keyword(s):  
Activation Energy ◽  
Bragg Peak ◽  
Isothermal Annealing ◽  
Direct Proof ◽  
In Situ Xrd ◽  
Columnar Grains ◽  
Pt Films ◽  
Heating Up ◽  
Kinetics Of

In this work we investigated the structural re-organization of thin nanocrystalline Pt films in the temperature range between 250 °C and 400 °C by in-situ XRD, GIXRD and XRR synchrotron experiments. A re-orientation of (111) atomic planes and a relaxation of residual stress occurs. After heating up, Bragg peak fringes can be observed in the diffractograms. They are a direct proof that the Pt films are built of (111) columnar grains which essentially reach the whole film thickness of about 40 nm. During isothermal annealing a relaxation of the dispersion parameter of the atomic planes takes place which is associated with an activation energy of (0.4 ± 0.1) eV.

Synthesis and Oxidation Kinetics of Sol-Gel and Sputtered Tantalum Nitride Thin Films

1995 ◽  
Vol 410 ◽  
Author(s):  
Gerald T. Kraus ◽  
Cory S. Oldweiler ◽  
Emmanuel P. Giannelis
Keyword(s):  
Thin Films ◽  
Activation Energy ◽  
Oxidation Kinetics ◽  
Sol Gel ◽  
Tantalum Nitride ◽  
Sputtered Films ◽  
Parabolic Oxidation ◽  
Sol Gel Films ◽  
Kinetics Of

ABSTRACTTantalum nitride thin films were produced by nitridation of sol-gel tantala thin films. The oxidation kinetics and the activation energy for oxidation were investigated and compared to those of sputtered tantalum nitride thin films. Data was gathered from in situ sheet resistance measurements taken between 550 and 720 K. Sol-gel films exhibited parabolic oxidation kinetics and had an activation energy of 1.9 eV. Sputtered films displayed quartic oxidation kinetics at lower temperatures tending toward cubic kinetics at higher temperatures and had an activation energy of 1.6 eV.

Sign in / Sign up

Export Citation Format

Share Document