Energy dissipation during desorption of reaction products: the role of substrate phonons

2004 ◽  
Vol 561 (2-3) ◽  
pp. 183-192 ◽  
Author(s):  
B Gumhalter ◽  
T Matsushima
Keyword(s):  
Energy Dissipation ◽  
Reaction Products

Role of Energy Dissipation and Surface Mobility in Heterogeneous Catalysis by Metals

1998 ◽  
Vol 63 (11) ◽  
pp. 1851-1868 ◽  
Author(s):  
Zlatko Knor ◽  
Jan Plšek
Keyword(s):  
Energy Dissipation ◽  
Gas Phase ◽  
Bimetallic Catalysts ◽  
Supported Catalysts ◽  
Bound State ◽  
Reaction Products ◽  
Atomic Steps ◽  
Surface Mobility ◽  
Species Mobility

The fundamental role of excess energy dissipation and of surface species mobility, both in the preparation of model metallic catalysts (bimetallic catalysts, bimetallic oxide-supported catalysts), and in the activation of reactant molecules on the catalyst surfaces (single crystals, bimetallic and bimetallic oxide-supported catalysts) are discussed. A generalized model of surface interactions is proposed which satisfactorily explains the trapping of particles from the gas phase at the atomic steps and recovery of the trapping sites due to migration of the trapped species towards flat terraces. Higher probability of encounter of these species with other reactants on flat terraces and easier desorption of the reaction products from there in comparison with the bound state at the edges of atomic steps can be expected. Results of FIM and FEM studies of Pt, Dy-W, Pd-W and Pd-Mo systems are used to illustrate selected features of the proposed general model.

Effect of cluster-gradient architecture of nanostructured topocomposites on features of tribointeraction with heterophased material

2020 ◽  
pp. 130-135
Author(s):  
D.N. Korotaev ◽  
K.N. Poleshchenko ◽  
E.N. Eremin ◽  
E.E. Tarasov
Keyword(s):  
Wear Resistance ◽  
Titanium Alloy ◽  
Energy Dissipation ◽  
Phase Structure ◽  
Diffusion Processes ◽  
Structural Phase ◽  
High Wear Resistance ◽  
Wear Characteristics ◽  
And Diffusion

The wear resistance and wear characteristics of cluster-gradient architecture (CGA) nanostructured topocomposites are studied. The specifics of tribocontact interaction under microcutting conditions is considered. The reasons for retention of high wear resistance of this class of nanostructured topocomposites are studied. The mechanisms of energy dissipation from the tribocontact zone, due to the nanogeometry and the structural-phase structure of CGA topocomposites are analyzed. The role of triboactivated deformation and diffusion processes in providing increased wear resistance of carbide-based topocomposites is shown. They are tested under the conditions of blade processing of heat-resistant titanium alloy.

THE EFFECT OF NONLINEAR DAMPING ON THE UNIVERSAL ESCAPE OSCILLATOR

1999 ◽  
Vol 09 (04) ◽  
pp. 735-744 ◽  
Author(s):  
MIGUEL A. F. SANJUÁN
Keyword(s):  
Energy Dissipation ◽  
Period Doubling ◽  
Nonlinear Damping ◽  
Basins Of Attraction ◽  
Period Doubling Bifurcation ◽  
Damping Coefficient ◽  
Nonlinear Dissipation ◽  
Fractal Basin Boundaries ◽  
Basin Boundaries

This paper analyzes the role of nonlinear dissipation on the universal escape oscillator. Nonlinear damping terms proportional to the power of the velocity are assumed and an investigation on its effects on the dynamics of the oscillator, such as the threshold of period-doubling bifurcation, fractal basin boundaries and how the basins of attraction are destroyed, is carried out. The results suggest that increasing the power of the nonlinear damping, has similar effects as of decreasing the damping coefficient for a linearly damped case, showing the very importance of the level or amount of energy dissipation.

scholarly journals Dynamic Crushing Analysis of a Three-Dimensional Re-Entrant Auxetic Cellular Structure

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 460 ◽  
Author(s):  
Tao Wang ◽  
Zhen Li ◽  
Liangmo Wang ◽  
Zhengdong Ma ◽  
Gregory Hulbert
Keyword(s):  
Energy Dissipation ◽  
Relative Density ◽  
Cellular Structure ◽  
Three Dimensional ◽  
Analytical Formula ◽  
Absorption Capacity ◽  
Plastic Energy ◽  
Theoretical Predictions ◽  
Auxetic Structure

Dynamic behaviors of the three-dimensional re-entrant auxetic cellular structure have been investigated by performing beam-based crushing simulation. Detailed deformation process subjected to various crushing velocities has been described, where three specific crushing modes have been identified with respect to the crushing velocity and the relative density. The crushing strength of the 3D re-entrant auxetic structure reveals to increase with increasing crushing velocity and relative density. Moreover, an analytical formula of dynamic plateau stress has been deduced, which has been validated to present theoretical predictions agreeing well with simulation results. By establishing an analytical model, the role of relative density on the energy absorption capacity of the 3D re-entrant auxetic structure has been further studied. The results indicate that the specific plastic energy dissipation is increased by increasing the relative density, while the normalized plastic energy dissipation has an opposite sensitivity to the relative density when the crushing velocity exceeds the critical transition velocity. The study in this work can provide insights into the dynamic property of the 3D re-entrant auxetic structure and provides an extensive reference for the crushing resistance design of the auxetic structure.

Direct evidence for the role of Maillard reaction products in protein cross-linking in milk powder during storage

2013 ◽  
Vol 31 (2) ◽  
pp. 83-91 ◽  
Author(s):  
Thao T. Le ◽  
John W. Holland ◽  
Bhesh Bhandari ◽  
Paul F. Alewood ◽  
Hilton C. Deeth
Keyword(s):  
Maillard Reaction ◽  
Direct Evidence ◽  
Milk Powder ◽  
Cross Linking ◽  
Maillard Reaction Products ◽  
Reaction Products ◽  
Protein Cross Linking
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