Molecular Insights into Dipole Relaxation Processes in Water–Lysine Mixtures

2019 ◽  
Vol 123 (28) ◽  
pp. 6056-6064 ◽  
Author(s):  
Alexandr Nasedkin ◽  
Silvina Cerveny ◽  
Jan Swenson
Keyword(s):  
Relaxation Processes ◽  
Dipole Relaxation

Thermophysical characterization of oil sands: 3. Electrical properties

1981 ◽  
Vol 18 (4) ◽  
pp. 742-750 ◽  
Author(s):  
M. Das ◽  
R. Thapar ◽  
K. Rajeshwar ◽  
J. DuBow
Keyword(s):  
Electrical Properties ◽  
Oil Sands ◽  
Activation Energies ◽  
Dielectric Constants ◽  
Relaxation Processes ◽  
Electrical Behavior ◽  
Frequency Range ◽  
Oil Sand ◽  
Dipole Relaxation ◽  
Mobile Charges

The electrical behavior of oil sand samples from the Athabasca, N. W. Asphalt Ridge, P. R. Spring, and Circle Cliffs deposits was studied in the frequency range 50 Hz – 103 MHz at ambient temperature and up to 550 °C. Anomalously high dielectric constants (ε′) were measured for these samples at low frequencies (<1 kHz) and at elevated temperatures (>200 °C). Accumulation of mobile charges at the phase boundaries in the oil sand matrix was probably responsible for this effect. These mobile charges were presumably created by thermal fragmentation of oil sand bitumen. The anomalous increase in the low-frequency (50 Hz – 1 MHz) ε′ values at temperatures above 150 °C was also traced to interfacial polarization effects. Dipole relaxation behavior was observed for the various samples at frequencies below ~1 kHz and in the temperature range 150–470 °C. Two distinct relaxation processes were identified. The low-temperature (150–400 °C) process had activation energies for dipole orientation ranging from 4.0 to 9.0 kJ/mol depending on the oil sand specimen. The second relaxation process, which occurred at temperatures above 400 °C, had significantly higher activation energies (30–34 kJ/mol). The occurrence of these dipole relaxation peaks may be relevant in the use of electrical techniques to map the location of pyrolysis zones in in situ oil sand retorts. Measurements on the Athabasca samples in the high-frequency range (1–103 MHz) revealed distinct changes in the dielectric parameters associated with the loss of water from the oil sand matrix. The electrical behavior of oil sands is represented in terms of an equivalent circuit model comprising discrete RC elements corresponding to various components in the oil sand matrix. Such a representation was found to aid in an assignment of the observed changes in the electrical properties with frequency and temperature to distinct physical or chemical processes occurring in the oil sand matrix.

Consequence of dipole relaxation processes in strong fields

1974 ◽  
Vol 17 (4) ◽  
pp. 559-560
Author(s):  
I. I. Kalyatskii ◽  
Yu. V. Volkov
Keyword(s):  
Relaxation Processes ◽  
Dipole Relaxation ◽  
Strong Fields

Activation energy of relaxation processes in chalcogenide glasses

2013 ◽  
Vol 34 (0) ◽  
pp. 59-63
Author(s):  
А. А. Горват ◽  
В. М. Кришеник ◽  
А. Е. Кріштофорій ◽  
В. В. Мінькович ◽  
О. А. Молнар
Keyword(s):  
Activation Energy ◽  
Chalcogenide Glasses ◽  
Relaxation Processes

Features of radiothermoluminescence of polypropylene and ethylene propylenediene elastomer SKEPT-4044 compositions with nanoscale metal-containing fillers

2020 ◽  
pp. 66-73
Author(s):  
A.M. Magerramov ◽  
◽  
N.I. Kurbanova ◽  
M.N. Bayramov ◽  
N.A. Alimirzoyeva ◽  
...  
Keyword(s):  
Transition Temperature ◽  
Molecular Mobility ◽  
Fe3o4 Nanoparticles ◽  
Low Temperatures ◽  
Frost Resistance ◽  
Relaxation Processes ◽  
Ethylene Propylene ◽  
Temperature Range ◽  
Β Relaxation

Using radiothermoluminescence (RTL), the molecular mobility features in the temperature range of 77-300 K were studied for the polypropylene (PP)/ethylene propylene diene elastomer SKEPT-4044 with NiO, Cu2O and Fe3O4 nanoparticles (NPs) based on ABS-acrylonitrile butadiene or SCS-divinyl styrene matrices. It has been shown that the introduction of nanofillers in PP significantly affects the nature and temperature of γ- and β-relaxation processes, while the region of manifestation of the β-process noticeably shifts to the region of low temperatures. Composites with Cu2O NPs have a higher β-transition temperature Tβ than composites with other NPs. It was found that PP/SKEPT-4044 composites with Cu2O NPs with a dispersion of 11-15 nm and acrylonitrile butadiene thermoplastics have optimal frost resistance compared to other compositions.

Weak Impacts and Relaxation Processes in Water and Other Liquids

2019 ◽  
Vol 53 (6) ◽  
pp. 955-959
Author(s):  
A. K. Lyashchenko ◽  
V. V. Dil’man ◽  
V. V. Taran
Keyword(s):  
Relaxation Processes

Electron Spin Decoherence by Nuclei

2018 ◽  
Author(s):  
M. M. Glazov
Keyword(s):  
Electron Spin ◽  
Spin Dynamics ◽  
Magnetic Moments ◽  
Host Lattice ◽  
Spin Model ◽  
Relaxation Processes ◽  
Nuclear Spins ◽  
Model Calculations ◽  
Spin Decoherence ◽  
Quantum Mechanical Approach

The discussion of the electron spin decoherence and relaxation phenomena via the hyperfine interaction with host lattice spins is presented here. The spin relaxation processes processes limit the conservation time of spin states as well as the response time of the spin system to external perturbations. The central spin model, where the spin of charge carrier interacts with the bath of nuclear spins, is formulated. We also present different methods to calculate the spin dynamics within this model. Simple but physically transparent semiclassical treatment where the nuclear spins are considered as largely static classical magnetic moments is followed by more advanced quantum mechanical approach where the feedback of electron spin dynamics on the nuclei is taken into account. The chapter concludes with an overview of experimental data and its comparison with model calculations.

scholarly journals A Dynamical Study of Fusion Hindrance with Nakajima-Zwanzig Projection Method

2021 ◽  
Author(s):  
Yasuhisa Abe ◽  
David Boilley ◽  
Quentin Hourdillé ◽  
Caiwan Shen
Keyword(s):  
Cross Sections ◽  
Degrees Of Freedom ◽  
Operator Method ◽  
Initial Distribution ◽  
Physical Parameters ◽  
Relaxation Processes ◽  
Fast Variable ◽  
Dynamical Study ◽  
Injection Point ◽  
Slow Variables

Abstract A new framework is proposed for the study of collisions between very heavy ions which lead to the synthesis of Super-Heavy Elements (SHE), to address the fusion hindrance phenomenon. The dynamics of the reaction is studied in terms of collective degrees of freedom undergoing relaxation processes with different time scales. The Nakajima-Zwanzig projection operator method is employed to eliminate fast variable and derive a dynamical equation for the reduced system with only slow variables. There, the time evolution operator is renormalised and an inhomogeneous term appears, which represents a propagation of the given initial distribution. The term results in a slip to the initial values of the slow variables. We expect that gives a dynamical origin of the so-called “injection point s” introduced by Swiatecki et al in order to reproduce absolute values of measured cross sections for SHE. A formula for the slip is given in terms of physical parameters of the system, which confirms the results recently obtained with a Langevin equation, and permits us to compare various incident channels.

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