scholarly journals Long-Time Non-Debye Kinetics of Molecular Desorption from Substrates with Frozen Disorder

Molecules ◽  
2020 ◽  
Vol 25 (16) ◽  
pp. 3662
Author(s):  
Victor N. Bondarev ◽  
Volodymyr V. Kutarov ◽  
Eva Schieferstein ◽  
Vladimir V. Zavalniuk

The experiments on the kinetics of molecular desorption from structurally disordered adsorbents clearly demonstrate its non-Debye behavior at “long” times. In due time, when analyzing the desorption of hydrogen molecules from crystalline adsorbents, attempts were made to associate this behavior with the manifestation of second-order effects, when the rate of desorption is limited by the rate of surface diffusion of hydrogen atoms with their subsequent association into molecules. However, the estimates made in the present work show that the dominance of second-order effects should be expected in the region of times significantly exceeding those where the kinetics of H2 desorption have long acquired a non-Debye character. To explain the observed regularities, an approach has been developed according to which frozen fluctuations in the activation energy of desorption play a crucial role in the non-Debye kinetics of the process. The obtained closed expression for the desorption rate has a transparent physical meaning and allows us to give a quantitative interpretation of a number of experiments on the desorption kinetics of molecules not only from crystalline (containing frozen defects) but also from amorphous adsorbents. The ways of further development of the proposed theory and its experimental verification are outlined.

Fuel ◽  
1977 ◽  
Vol 56 (1) ◽  
pp. 65-69 ◽  
Author(s):  
Daniel Finucane ◽  
John H. George ◽  
H. Gordon Harris

2020 ◽  
Vol 117 (24) ◽  
pp. 243501
Author(s):  
Anna N. Matsukatova ◽  
Andrey V. Emelyanov ◽  
Anton A. Minnekhanov ◽  
Aleksandr A. Nesmelov ◽  
Artem Yu. Vdovichenko ◽  
...  

ce/papers ◽  
2021 ◽  
Vol 4 (2-4) ◽  
pp. 2249-2254
Author(s):  
Jian‐Wei He ◽  
Lei Zhao ◽  
Yao‐Peng Liu ◽  
Siu‐Lai Chan

1985 ◽  
Vol 11 (4) ◽  
pp. 598-610 ◽  
Author(s):  
Edward Zamble ◽  
G. Marilyn Hadad ◽  
John B. Mitchell ◽  
Tim R. H. Cutmore

1979 ◽  
Vol 100 (1-2) ◽  
pp. 607-624 ◽  
Author(s):  
M. Sluyters-Rehbach ◽  
J. Struys ◽  
J.H. Sluyters

1984 ◽  
Vol 109 (4) ◽  
pp. 398-403 ◽  
Author(s):  
J.C. Evans ◽  
A.Y. Obaid ◽  
C.C. Rowlands

2017 ◽  
Vol 10 (2) ◽  
pp. 333-357
Author(s):  
D.M. OLIVEIRA ◽  
N.A. SILVA ◽  
C.C. RIBEIRO ◽  
S.E.C. RIBEIRO

Abstract In this paper the simplified method to evaluate final efforts using γ z coefficient is studied considering the variation of the second order effects with the height of the buildings. With this purpose, several reinforced concrete buildings of medium height are analyzed in first and second order using ANSYS software. Initially, it was checked that the (z coefficient should be used as magnifier of first order moments to evaluate final second order moments. Therefore, the study is developed considering the relation (final second order moments/ first order moments), calculated for each story of the structures. This moments relation is called magnifier of first order moments, "γ", and, in the ideal situation, it must coincide with the γ z value. However, it is observed that the reason γ /γ z varies with the height of the buildings. Furthermore, using an statistical analysis, it was checked that γ /γ z relation is generally lower than 1.05 and varies significantly in accordance with the considered building and with the presence or not of symmetry in the structure.


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