Unidirectional Energy Transfer in Conjugated Molecules: The Crucial Role of High-Frequency C≡C Bonds

2010 ◽  
Vol 1 (18) ◽  
pp. 2699-2704 ◽  
Author(s):  
S. Fernandez-Alberti ◽  
Valeria D. Kleiman ◽  
S. Tretiak ◽  
Adrian E. Roitberg
Keyword(s):  
Energy Transfer ◽  
High Frequency ◽  
Crucial Role ◽  
Conjugated Molecules

Energy Transfer from High-Frequency to Low-Frequency Modes in Structures

1995 ◽  
Vol 117 (B) ◽  
pp. 186-195 ◽  
Author(s):  
A. H. Nayfeh ◽  
D. T. Mook
Keyword(s):  
Energy Transfer ◽  
High Frequency ◽  
Large Amplitude ◽  
Low Frequency ◽  
Internal Resonances ◽  
Parametric Resonances ◽  
High Frequency Excitation ◽  
Frequency Excitation ◽  
Low Amplitude

A perspective of the mechanisms by which energy is transferred from high- to low-frequency modes is presented. The focus is on some recent experiments that reveal how a low-amplitude high-frequency excitation can produce a large-amplitude low-frequency response. Such a phenomenon is potentially harmful, if not catastrophic. Specifically, these experiments clarify the role of internal resonances, combination external and parametric resonances, and the interactions among modes of widely spaced frequencies.

Energy Transfer from High-Frequency to Low-Frequency Modes in Structures

1995 ◽  
Vol 117 (B) ◽  
pp. 186-195 ◽  
Author(s):  
A. H. Nayfeh ◽  
D. T. Mook
Keyword(s):  
Energy Transfer ◽  
High Frequency ◽  
Large Amplitude ◽  
Low Frequency ◽  
Internal Resonances ◽  
Parametric Resonances ◽  
High Frequency Excitation ◽  
Frequency Excitation ◽  
Low Amplitude

A perspective of the mechanisms by which energy is transferred from high- to low-frequency modes is presented. The focus is on some recent experiments that reveal how a low-amplitude high-frequency excitation can produce a large-amplitude low-frequency response. Such a phenomenon is potentially harmful, if not catastrophic. Specifically, these experiments clarify the role of internal resonances, combination external and parametric resonances, and the interactions among modes of widely spaced frequencies.

Epitaxial YBa2Cu3O7-8 films : Crucial role of growth-induced linear defects in microwave properties

2001 ◽  
Vol 11 (PR11) ◽  
pp. Pr11-47-Pr11-52
Author(s):  
V. M. Pan ◽  
V. S. Flis ◽  
V. A. Komashko ◽  
O. G. Plys ◽  
C. G. Tretiatchenko ◽  
...  
Keyword(s):  
Crucial Role ◽  
Microwave Properties ◽  
Linear Defects

Adiabatic large polarons in anisotropic molecular crystals

2011 ◽  
Vol 35 (1) ◽  
pp. 15-27
Author(s):  
Zoran Ivić ◽  
Željko Pržulj
Keyword(s):  
Energy Transfer ◽  
Effective Mass ◽  
Molecular Crystals ◽  
Single Chain ◽  
Proper Understanding ◽  
One Dimensional ◽  
Interchain Coupling ◽  
Large Polaron ◽  
The One

Adiabatic large polarons in anisotropic molecular crystals We study the large polaron whose motion is confined to a single chain in a system composed of the collection of parallel molecular chains embedded in threedimensional lattice. It is found that the interchain coupling has a significant impact on the large polaron characteristics. In particular, its radius is quite larger while its effective mass is considerably lighter than that estimated within the one-dimensional models. We believe that our findings should be taken into account for the proper understanding of the possible role of large polarons in the charge and energy transfer in quasi-one-dimensional substances.

Calculation-and-experimental estimation of the role of the frequency ratio in changing the endurance at two-frequency deformation modes

2019 ◽  
Vol 85 (1(I)) ◽  
pp. 64-71 ◽  
Author(s):  
M. M. Gadenin
Keyword(s):  
High Frequency ◽  
Experimental Studies ◽  
Low Frequency ◽  
Reduction Factor ◽  
Single Frequency ◽  
Cyclic Loads ◽  
Small Ratio ◽  
Harmonic Components ◽  
Deformation Modes

The cycle configuration at two-frequency loading regimes depends on the number of parameters including the absolute values of the frequencies and amplitudes of the low-frequency and high-frequency loads added during this mode, the ratio of their frequencies and amplitudes, as well as the phase shift between these harmonic components, the latter having a significant effect only with a small ratio of frequencies. Presence of such two-frequency regimes or service loading conditions for parts of machines and structures schematized by them can significantly reduce their endurance. Using the results of experimental studies of changes in the endurance of a two-frequency loading of specimens of cyclically stable, cyclically softened and cyclically hardened steels under rigid conditions we have shown that decrease in the endurance under the aforementioned conditions depends on the ratio of frequencies and amplitudes of operation low-frequency low-cycle and high-frequency vibration stresses, and, moreover, the higher the level of the ratios of amplitudes and frequencies of those stacked harmonic processes of loading the greater the effect. It is shown that estimation of such a decrease in the endurance compared to a single frequency loading equal in the total stress (strains) amplitudes can be carried out using an exponential expression coupling those endurances through a parameter (reduction factor) containing the ratio of frequencies and amplitudes of operation cyclic loads and characteristic of the material. The reduction is illustrated by a set of calculation-experimental curves on the corresponding diagrams for each of the considered types of materials and compared with the experimental data.

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