scholarly journals Mesoscopic collective dynamics in liquids and the Dual Model

2021 ◽  
Author(s):  
Fabio Peluso
Keyword(s):  
Elastic Waves ◽  
Degrees Of Freedom ◽  
Energy Transport ◽  
Wave Packets ◽  
Relaxation Times ◽  
High Energy ◽  
Thermodynamic Quantities ◽  
Dual Model ◽  
Statistical Population ◽  
Collective Dynamics

Abstract In the present article it is shown how a series of experimental evidences and theoretical developments on liquid modelling, gathered for the first time, can all be framed in a mesoscopic view of liquids that are hypothesized as constituted by a population of wave packets, responsible for the propagation of elastic and thermal perturbations, and of dynamic aggregates of molecules, in continuous re-arrangement, diving in an ocean of amorphous, disordered liquid. This model, dubbed Dual Model of Liquids, is complementary to the Phonon theory of Liquid Thermodynamics, recently proposed by an independent group. The pseudo-crystalline dynamic structures, whose presence in liquids is evidenced by high energy inelastic scattering experiments, interact with a statistical population of harmonic elastic waves and anharmonic wave-packets propagating within and among the structures themselves, respectively. The expression for the interaction term is derived from “first principles” based on general considerations related to the pressure exerted by elastic waves travelling in condensed media. The anharmonic character of the interaction allows the exchange not only of energy but also of momentum between wave packets and clusters, thus determining both the displacement of the latter within the medium, and the redistribution of the energy between external, or translatory degrees of freedom of the clusters, and internal collective, vibratory degrees. Using these concepts it is possible to calculate some dynamic and thermodynamic quantities concerning the dynamics of liquids. Moreover, the interpretation of the relaxation times of the processes involved in momentum and energy transport is given, their Order-of-Magnitude is calculated, and the way in which these times are involved in the different phases of the collective dynamics of liquids is discussed. A comparison is provided with results obtained in the frame of PLT and with the forecasts for the visco-elastic transition regions. In the last part of the paper, some experiments are suggested that should be performed to provide additional details to the model.

scholarly journals Mesoscopic collective dynamics in liquids and the Dual Model

2021 ◽  
Author(s):  
Fabio Peluso
Keyword(s):  
Elastic Waves ◽  
Energy Transport ◽  
Wave Packets ◽  
Relaxation Times ◽  
High Energy ◽  
Thermodynamic Quantities ◽  
Dual Model ◽  
Statistical Population ◽  
Collective Dynamics ◽  
Theoretical Developments

Abstract In the present article it is shown how a series of experimental evidences and theoretical developments on liquid modelling, gathered for the first time, can all be framed in a mesoscopic view of liquids that are hypothesized as constituted by a population of wave packets, responsible for the propagation of elastic and thermal perturbations, and of dynamic aggregates of molecules, in continuous re-arrangement, diving in an ocean of amorphous, disordered liquid. This model, dubbed Dual Model of Liquids (DML), is complementary to the Phonon theory of Liquid Thermodynamics (PLT), recently proposed by an independent group. The pseudo-crystalline dynamic structures, evidenced by high energy inelastic scattering experiments, interact with a statistical population of harmonic elastic waves and anharmonic wave-packets propagating within and among the structures themselves, respectively. The expression for the interaction term is derived from “first principles” based on general considerations related to the pressure exerted by elastic waves travelling in condensed media. The anharmonic character of the interaction allows the exchange not only of energy but also of momentum between wave packets and clusters, thus determining both the displacement of the latter within the medium, and the redistribution of the energy between external, or translatory degrees of freedom of the clusters, and internal collective, vibratory degrees. Using these concepts it is possible to calculate some dynamic and thermodynamic quantities concerning the dynamics of liquids. Moreover, the interpretation of the relaxation times of the processes involved in momentum and energy transport is given, their Order-of-Magnitude is calculated, and the way in which these times are involved in the different phases of the collective dynamics of liquids is discussed. A comparison is provided with results obtained in the frame of PLT and with the forecasts for the visco-elastic transition regions, in particular with systems exhibiting k-gap.In the last part of the paper, theoretical developments and experiments are suggested that should be performed to provide additional details to the model.

scholarly journals Isochoric specific heat in the Dual Model of Liquids and comparison with the Phonon theory of Liquid Thermodynamics

2021 ◽  
Author(s):  
Fabio Peluso
Keyword(s):  
Specific Heat ◽  
Degrees Of Freedom ◽  
High Energy ◽  
Dual Model ◽  
Mesoscopic Level ◽  
Energy And Momentum ◽  
Analogous Expression ◽  
High Energy Scattering ◽  
Limiting Values ◽  
Phonon Theory

Abstract We continue in this paper to illustrate the implications of the Dual Model of Liquids (DML) by deriving the expression for the isochoric specific heat as a function of the collective degrees of freedom available at a given temperature and comparing it with the analogous expression obtained in the Phonon Theory of Liquid Thermodynamics. The Dual Model of Liquids has been recently proposed as a model describing the dynamics of liquids at the mesoscopic level. Bringing together the early pictures of Brillouin and Frenkel and the recent experimental outcomes obtained by means of high energy scattering, liquids are considered in the DML as constituted by a population of wave packets, responsible for the propagation of elastic and thermal perturbations, and of dynamic aggregates of molecules, in continuous re-arrangement, diving in an ocean of amorphous, disordered liquid. The collective degrees of freedom contribute to the exchange of energy and momentum between the material particles and the lattice particles, which the liquids are supposed to be composed of in the DML.First, we show that the expression obtained for the specific heat in the DML is in line with the experimental results. Second, its comparison with that of the Phonon Theory of Liquid Thermodynamics allows getting interesting insights about the limiting values of the collective degrees of freedom and on that of the isobaric thermal expansion coefficient, two quantities that appear related to each other in this framework

scholarly journals The emerging technology of biohybrid micro-robots: a review

2021 ◽  
Author(s):  
Zening Lin ◽  
Tao Jiang ◽  
Jianzhong Shang
Keyword(s):  
Self Assembly ◽  
Degrees Of Freedom ◽  
High Energy ◽  
Living Cells ◽  
Multiple Degrees Of Freedom ◽  
The Past ◽  
Great Prevalence ◽  
Performance Decline ◽  
High Energy Efficiency ◽  
Living Tissues

Abstract In the past few decades, robotics research has witnessed an increasingly high interest in miniaturized, intelligent, and integrated robots. The imperative component of a robot is the actuator that determines its performance. Although traditional rigid drives such as motors and gas engines have shown great prevalence in most macroscale circumstances, the reduction of these drives to the millimeter or even lower scale results in a significant increase in manufacturing difficulty accompanied by a remarkable performance decline. Biohybrid robots driven by living cells can be a potential solution to overcome these drawbacks by benefiting from the intrinsic microscale self-assembly of living tissues and high energy efficiency, which, among other unprecedented properties, also feature flexibility, self-repair, and even multiple degrees of freedom. This paper systematically reviews the development of biohybrid robots. First, the development of biological flexible drivers is introduced while emphasizing on their advantages over traditional drivers. Second, up-to-date works regarding biohybrid robots are reviewed in detail from three aspects: biological driving sources, actuator materials, and structures with associated control methodologies. Finally, the potential future applications and major challenges of biohybrid robots are explored. Graphic abstract

scholarly journals Recent Developments of the Liège Intranuclear Cascade Model in View of its Use into High-energy Transport Codes

2014 ◽  
Vol 118 ◽  
pp. 312-315 ◽  
Author(s):  
S. Leray ◽  
A. Boudard ◽  
B. Braunn ◽  
J. Cugnon ◽  
J.C. David ◽  
...  
Keyword(s):  
Energy Transport ◽  
High Energy ◽  
Cascade Model ◽  
Intranuclear Cascade ◽  
Recent Developments

scholarly journals Spin-Orbit Entanglement in Time Evolution of Radial Wave Packets in Hydrogenic Systems

2004 ◽  
Vol 11 (04) ◽  
pp. 401-409
Author(s):  
Marcin Turek ◽  
Piotr Rozmej
Keyword(s):  
Wave Packet ◽  
Time Evolution ◽  
Time Scale ◽  
Degrees Of Freedom ◽  
Wave Packets ◽  
Characteristic Time Scale ◽  
Radial Wave ◽  
Mean Values ◽  
Breathing Motion ◽  
Wave Packet Revival

Time evolution of radial wave packets built from the eigenstates of Dirac equation for a hydrogenic system is considered. Radial wave packets are constructed from the states of different n quantum numbers and the same lowest angular momentum. In general they exhibit a kind of breathing motion with dispersion and (partial) revivals. Calculations show that for some particular preparations of the wave packet one can observe interesting effects in spin motion, coming from inherent entanglement of spin and orbital degrees of freedom. These effects manifest themselves through some oscillations in the mean values of spin operators and through changes of spatial probability density carried by upper and lower components of the wave function. It is also shown that the characteristic time scale of predicted effects (called T ls ) is much smaller for radial wave packets than in other cases, reaching values comparable to (or even less than) the time scale for the wave packet revival.

scholarly journals Near-Field Measurement of Six Degrees of Freedom Mining-Induced Tremors in Lower Silesian Copper Basin

Sensors ◽  
2020 ◽  
Vol 20 (23) ◽  
pp. 6801
Author(s):  
Krzysztof Fuławka ◽  
Witold Pytel ◽  
Bogumiła Pałac-Walko
Keyword(s):  
Seismic Wave ◽  
Degrees Of Freedom ◽  
Seismic Waves ◽  
Near Field ◽  
High Energy ◽  
Rotational Component ◽  
Empirical Formulas ◽  
Six Degrees Of Freedom ◽  
The Impact

The impact of seismicity on structures is one of the key problems of civil engineering. According to recent knowledge, the reliable analysis should be based on both rotational and translational components of the seismic wave. To determine the six degrees of freedom (6-DoF) characteristic of mining-induced seismicity, two sets of seismic posts were installed in the Lower Silesian Copper Basin, Poland. Long-term continuous 6-DoF measurements were conducted with the use of the R-1 rotational seismometer and EP-300 translational seismometer. In result data collection, the waveforms generated by 39 high-energy seismic events were recorded. The characteristic of the rotational component of the seismic waves were described in terms of their amplitude and frequency characteristics and were compared with translational measurements. The analysis indicated that the characteristic of the rotational component of the seismic wave differs significantly in comparison to translational ones, both in terms of their amplitude and frequency distribution. Also, attenuation of rotational and translational components was qualitatively compared. Finally, the empirical formulas for seismic rotation prediction in the Lower Silesian Copper Basin were developed and validated.

scholarly journals CP VIOLATION AND BEAUTY DECAYS — A CASE STUDY OF HIGH IMPACT, HIGH SENSITIVITY AND EVEN HIGH PRECISION PHYSICS

2000 ◽  
Vol 15 (08) ◽  
pp. 1079-1156
Author(s):  
I. I. BIGI
Keyword(s):  
Cp Violation ◽  
Degrees Of Freedom ◽  
High Energy Physics ◽  
Dipole Moments ◽  
High Sensitivity ◽  
High Energy ◽  
New Physics ◽  
B Decays ◽  
New Paradigm ◽  
Parametric Reliability

The narrative of these lectures contains three main threads: (i) CP violation despite having so far been observed only in the decays of neutral kaons has been recognized as a phenomenon of truly fundamental importance. The KM ansatz constitutes the minimal implementation of CP violation: without requiring unknown degrees of freedom it can reproduce the known CP phenomenology in a nontrivial way. (ii) The physics of beauty hadrons — in particular their weak decays — opens a novel window onto fundamental dynamics: they usher in a new quark family (presumably the last one); they allow us to determine fundamental quantities of the Standard Model like the b quark mass and the CKM parameters V(cb), V(ub), V(ts) and V(td); they exhibit speedy or even rapid [Formula: see text] oscillations. (iii) Heavy Quark Expansions allow us to treat B decays with an accuracy that would not have been thought possible a mere decade ago. These three threads are joined together in the following manner: (a) Huge CP asymmetries are predicted in B decays, which represents a decisive test of the KM paradigm for CP violation. (b) Some of these predictions are made with high parametric reliability, which (c) can be translated into numerical precision through the judicious employment of novel theoretical technologies. (d) Beauty decays thus provide us with a rich and promising field to search for New Physics and even study some of its salient features. At the end of it there might quite possibly be a New Paradigm for High Energy Physics. There will be some other threads woven into this tapestry: electric dipole moments, and CP violation in other strange and in charm decays.

A 3D passive dynamic biped with yaw and roll compensation

Robotica ◽  
2001 ◽  
Vol 19 (3) ◽  
pp. 275-284 ◽  
Author(s):  
M. Wisse ◽  
A. L. Schwab ◽  
R. Q. vd. Linde
Keyword(s):  
Degrees Of Freedom ◽  
High Energy ◽  
Roll Motion ◽  
Multibody Model ◽  
The Third ◽  
High Energy Efficiency ◽  
Dynamic Compensator ◽  
Third Dimension ◽  
The Stability ◽  
Natural Dynamics

Autonomous walking bipedal machines, possibly useful for rehabilitation and entertainment purposes, need a high energy efficiency, offered by the concept of ‘Passive Dynamic Walking' (exploitation of the natural dynamics of the robot). 2D passive dynamic bipeds have been shown to be inherently stable, but in the third dimension two problematic degrees of freedom are introduced: yaw and roll.We propose a design for a 3D biped with a pelvic body as a passive dynamic compensator, which will compensate for the undesired yaw and roll motion, and allow the rest of the robot to move as if it were a 2D machine. To test our design, we perform numerical simulations on a multibody model of the robot. With limit cycle analysis we calculate the stability of the robot when walking at its natural speed.The simulation shows that the compensator, indeed, effectively compensates for both the yaw and the roll motion, and that the walker is stable.

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