Non equilibrium oscillatory relaxation processes across biological membranes

1989 ◽  
Vol 41 ◽  
pp. 43-51
Author(s):  
Alfonso M. Liquori
Keyword(s):  
Biological Membranes ◽  
Relaxation Processes ◽  
Oscillatory Relaxation ◽  
Non Equilibrium

Shock discontinuity zone effect: the main factor in the explosive decomposition detonation process

1992 ◽  
Vol 339 (1654) ◽  
pp. 355-364 ◽  
Keyword(s):  
Degrees Of Freedom ◽  
Thermal Ionization ◽  
Relaxation Processes ◽  
Explosive Decomposition ◽  
Time Duration ◽  
Active Particles ◽  
Condensed Explosives ◽  
Discontinuity Zone ◽  
Electronically Excited ◽  
Non Equilibrium

A new qualitative conception of the detonation mechanism in condensed explosives has been developed on the basis of experimental and numerical modelling data. According to the conception the mechanism consists of two stages: non-equilibrium and equilibrium. The mechanism regularities are explosive characteristics and they do not depend on explosive charge structure (particle size, nature of filler in the pores, explosive state, liquid or solid, and so on). The tremendous rate of loading inside the detonation wave shock discontinuity zone ( ca. 10 -13 s) is responsible for the origin of the non-equilibrium stage. For this reason, the kinetic part of the shock compression energy is initially absorbed only by the translational degrees of freedom of the explosive molecules. It involves the appearance of extremely high translational temperatures for the polyatomic molecules. In the course of the translational-vibrational relaxation processes (that is, during the first non-equilibrium stage of ca. 10 -10 s time duration) the most rapidly excited vibrational degrees of freedom can accumulate surplus energy, and the corresponding bonds decompose faster than behind the front at the equilibrium stage. In addition to this process, the explosive molecules become electronically excited and thermal ionization becomes possible inside the translational temperature overheat zone. The molecules thermal decomposition as well as their electronic excitation and thermal ionization result in some active particles (radicals, ions) being created. The active particles and excited molecules govern the explosive detonation decomposition process behind the shock front during the second equilibrium stage. The activation energy is usually low, so that during this stage the decomposition proceeds extremely rapidly. Therefore the experimentally observed dependence of the detonation decomposition time for condensed explosives is rather weak.

The role of non-equilibrium fluxes in the relaxation processes of the linear chemical master equation

2014 ◽  
Vol 141 (6) ◽  
pp. 065102 ◽  
Author(s):  
Luciana Renata de Oliveira ◽  
Armando Bazzani ◽  
Enrico Giampieri ◽  
Gastone C. Castellani
Keyword(s):  
Master Equation ◽  
Chemical Master Equation ◽  
Relaxation Processes ◽  
Non Equilibrium

scholarly journals Stochastic analysis of dynamic processes in the solar activity

2021 ◽  
Vol 2103 (1) ◽  
pp. 012018
Author(s):  
E Y Kostina ◽  
E V Khusaenova ◽  
A O Andreev ◽  
R Hudec ◽  
Y A Nefedyev
Keyword(s):  
Solar Activity ◽  
Stochastic Analysis ◽  
Methodological Approach ◽  
Kinetic Equations ◽  
Quantitative Measure ◽  
Relaxation Processes ◽  
Complex Objects ◽  
Time Modeling ◽  
Active Processes ◽  
Non Equilibrium

Abstract Natural processes existing in complex objects of inanimate and living matter are of a stochastic and non-equilibrium nature. The main problem in the study of such systems is to determine the value of entropy as a quantitative measure of the uncertainty and systematicity of states of dynamical systems in different phase spaces. This paper presents a new method for analyzing active processes of solar dynamics using the theory of non-Markov random discrete processes (NMRDP). The NMRDP theory is based on the Zwanzig-Mori kinetic equations in a finite-difference discrete interpretation. This is consistent with the concept of non-equilibrium statistical condensed matter physics. Qualitative information about the set of behavioral patterns, relaxation processes, dynamic characteristics and internal properties of solar activity can be obtained using NMRDP modeling by the author’s methodological approach developed in this work. This approach is focused on the analysis of spectral frequency memory functions, dynamic orthogonal parameters, phase transformations, relaxation and kinetic processes and self-organization in complex physical systems. In this work, for modeling NMRDP, the author’s software package APSASA (automated program for solar activity stochastic analysis) was used, which also allows predicting the trend of solar activity for a limited period of time. Modeling NMRDP associated with active processes occurring on the Sun made it possible to build a mathematical model with whose help it is possible to study the regularities and randomness of stochastic processes, as well as to reveal the patterns arising from the recurrence and periodicity of solar activity.

Numerical and theoretical study of the shock stand-off distance in non-equilibrium flows

2008 ◽  
Vol 607 ◽  
pp. 167-197 ◽  
Author(s):  
N. BELOUAGGADIA ◽  
H. OLIVIER ◽  
R. BRUN
Keyword(s):  
Vibrational Energy ◽  
Physical Modelling ◽  
Relaxation Processes ◽  
Blunt Bodies ◽  
Explicit Formulae ◽  
Insight Into ◽  
Simple Ideal ◽  
Good Agreement ◽  
Non Equilibrium

A theoretical model based on a quasi-one-dimensional formulation is developed which allows determination of the shock stand-off distance at the stagnation point of blunt bodies in hypersonic non-equilibrium flows. Despite the simple ideal dissociating gas model implemented in the theoretical approach, it gives insight into the main physics governing the shock stand-off problem. More detailed and precise data are obtained by a numerical simulation where vibrational and chemical relaxation processes as well as their interactions are taken into account. The physical modelling of these processes is based on a kinetic approach and on a generalized Chapman–Enskog method of solving the Boltzmann equation. Explicit formulae for rate constants and vibrational energy consumption are derived and incorporated into the general conservation equations. Good agreement between theoretical, numerical and experimental results is achieved which ensures a reliable and mutual validation of the different methods.

THE POLARON EFFECTS AND RELAXATION OF NON-EQUILIBRIUM ELECTRONS IN THE QUASI-TWO-DIMENSIONAL SYSTEMS

1991 ◽  
Vol 05 (02) ◽  
pp. 139-149 ◽  
Author(s):  
N.M. GUSEINOV ◽  
K.A. RUSTAMOV ◽  
S.M. SEYID-RZAYEVA
Keyword(s):  
Three Dimensional ◽  
Energy Shift ◽  
Electron System ◽  
Relaxation Processes ◽  
Electron Mass ◽  
Two Dimensional ◽  
Effective Electron ◽  
Dimensional Electron System ◽  
Analytical Expressions ◽  
Non Equilibrium

The problem on weak-coupling polaron in the quasi-two-dimensional electron system is solved. Analytical expressions for polaron energy shift of the subband and polaron contribution to the effective electron mass with arbitrary quantum well width are found. The expressions obtained give the well-known values for two- and three-dimensional limiting cases. A comparison of the polaron contribution to the mass with the available experimental data is carried out. Energy relaxation processes of non-equilibrium quasi-two-dimensional electrons with the optic phonon emission are also considered. General analytical expressions for the frequencies of intra-subband and inter-subband transitions for the threshold electron energy are obtained.

Electron Diffraction of Wet Biological Membranes

1974 ◽  
Vol 32 ◽  
pp. 158-159
Author(s):  
S.W. Hui ◽  
D.F. Parsons
Keyword(s):  
Electron Diffraction ◽  
Data Collection ◽  
Biological Membranes ◽  
Small Areas ◽  
Electron Diffraction Technique ◽  
Electron Microscopes ◽  
Collection Time ◽  
Camera Length

The development of the hydration stages for electron microscopes has opened up the application of electron diffraction in the study of biological membranes. Membrane specimen can now be observed without the artifacts introduced during drying, fixation and staining. The advantages of the electron diffraction technique, such as the abilities to observe small areas and thin specimens, to image and to screen impurities, to vary the camera length, and to reduce data collection time are fully utilized. Here we report our pioneering work in this area.

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