Transport Processes in Anisotropic Fluids II. Coupling of Momentum and Energy Transport in a Nematic Mesophase

1969 ◽  
Vol 6 (2) ◽  
pp. 255-271 ◽  
Author(s):  
Jay Fisher ◽  
A. G. Fredrickson
Keyword(s):  
Energy Transport ◽  
Transport Processes ◽  
Nematic Mesophase ◽  
Anisotropic Fluids

scholarly journals Noise-Assisted Discord-Like Correlations in Light-Harvesting Photosynthetic Complexes

2021 ◽  
Vol 3 (2) ◽  
pp. 262-271
Author(s):  
Pablo Reséndiz-Vázquez ◽  
Ricardo Román-Ancheyta ◽  
Roberto León-Montiel
Keyword(s):  
Potential Role ◽  
Energy Transport ◽  
Light Harvesting ◽  
Quantum Correlations ◽  
Transport Processes ◽  
Quantum Evolution ◽  
Light Harvesting Complexes ◽  
Transport Efficiency ◽  
Photovoltaic Materials ◽  
Photosynthetic Complexes

Transport phenomena in photosynthetic systems have attracted a great deal of attention due to their potential role in devising novel photovoltaic materials. In particular, energy transport in light-harvesting complexes is considered quite efficient due to the balance between coherent quantum evolution and decoherence, a phenomenon coined Environment-Assisted Quantum Transport (ENAQT). Although this effect has been extensively studied, its behavior is typically described in terms of the decoherence’s strength, namely weak, moderate or strong. Here, we study the ENAQT in terms of quantum correlations that go beyond entanglement. Using a subsystem of the Fenna–Matthews–Olson complex, we find that discord-like correlations maximize when the subsystem’s transport efficiency increases, while the entanglement between sites vanishes. Our results suggest that quantum discord is a manifestation of the ENAQT and highlight the importance of beyond-entanglement correlations in photosynthetic energy transport processes.

scholarly journals The Assembly of Porphyrin Systems in Well-Defined Nanostructures: An Update

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4307 ◽  
Author(s):  
Gabriele Magna ◽  
Donato Monti ◽  
Corrado Di Natale ◽  
Roberto Paolesse ◽  
Manuela Stefanelli
Keyword(s):  
Self Assembly ◽  
Energy Transport ◽  
Functional Materials ◽  
Building Blocks ◽  
Spatial Arrangement ◽  
Transport Processes ◽  
Internal Electric Field ◽  
Porphyrin Derivatives ◽  
Molecular Building Blocks ◽  
The Individual

The interest in assembling porphyrin derivatives is widespread and is accounted by the impressive impact of these suprastructures of controlled size and shapes in many applications from nanomedicine and sensors to photocatalysis and optoelectronics. The massive use of porphyrin dyes as molecular building blocks of functional materials at different length scales relies on the interdependent pair properties, consisting of their chemical stability/synthetic versatility and their quite unique physicochemical properties. Remarkably, the driven spatial arrangement of these platforms in well-defined suprastructures can synergically amplify the already excellent properties of the individual monomers, improving conjugation and enlarging the intensity of the absorption range of visible light, or forming an internal electric field exploitable in light-harvesting and charge-and energy-transport processes. The countless potentialities offered by these systems means that self-assembly concepts and tools are constantly explored, as confirmed by the significant number of published articles related to porphyrin assemblies in the 2015–2019 period, which is the focus of this review.

scholarly journals A generalized fractional-order elastodynamic theory for non-local attenuating media

2020 ◽  
Vol 476 (2238) ◽  
pp. 20200200 ◽  
Author(s):  
Sansit Patnaik ◽  
Fabio Semperlotti
Keyword(s):  
Fractional Order ◽  
Elastic Waves ◽  
Energy Transport ◽  
Transport Processes ◽  
Non Local ◽  
The Many ◽  
Propagation Of Elastic Waves ◽  
And Diffusion ◽  
Fully Coupled ◽  
Theoretical Results

This study presents a generalized elastodynamic theory, based on fractional-order operators, capable of modelling the propagation of elastic waves in non-local attenuating solids and across complex non-local interfaces. Classical elastodynamics cannot capture hybrid field transport processes that are characterized by simultaneous propagation and diffusion. The proposed continuum mechanics formulation, which combines fractional operators in both time and space, offers unparalleled capabilities to predict the most diverse combinations of multiscale, non-local, dissipative and attenuating elastic energy transport mechanisms. Despite the many features of this theory and the broad range of applications, this work focuses on the behaviour and modelling capabilities of the space-fractional term and on its effect on the elastodynamics of solids. We also derive a generalized fractional-order version of Snell’s Law of refraction and of the corresponding Fresnel’s coefficients. This formulation allows predicting the behaviour of fully coupled elastic waves interacting with non-local interfaces. The theoretical results are validated via direct numerical simulations.

Comparison between experiment and theory

1987 ◽  
Vol 322 (1563) ◽  
pp. 173-188 ◽  
Keyword(s):  
Simple Model ◽  
Temperature Profile ◽  
Classical Theory ◽  
Thermal Conduction ◽  
Energy Transport ◽  
Magnetic Confinement ◽  
Transport Processes ◽  
Coulomb Collisions ◽  
Magnetic Surfaces

In the idealized theory of toroidal magnetic confinement, the plasma is supposed to be embedded in a nested set of topologically toroidal magnetic surfaces. The plasma is assumed to be stable so that all transport processes, such as thermal conduction, are determined only by Coulomb collisions between the particles. In this paper, we first compare the experimental results with the predictions of this theory. The actual energy transport rate is found to be much higher than that predicted. This is believed to be due to instability processes in the plasma although there remains the possibility that the idealized or classical theory is not complete. The role of electrostatic and of magnetic instabilities is discussed. Finally, the consequences of a simple model, in which the form of the temperature profile is fixed, are discussed.

Ein Zusammenhang zwischen Anregungszuständen von Molekülen und biologischer Wirkung, wie Strahlensensibilisierung und Kanzerogenität / A Correlation between the Properties of Excited States of Molecules and Biological Activity, as Radiosensibilization and Carcinogenic Activity

1973 ◽  
Vol 28 (9-10) ◽  
pp. 517-522
Author(s):  
Fritz A. Popp
Keyword(s):  
Electronic Structure ◽  
Biological Activity ◽  
Excited States ◽  
Energy Transport ◽  
Transport Processes ◽  
Excited Singlet ◽  
Carcinogenic Activity ◽  
Uracil Derivatives ◽  
Singlet States ◽  
Excited Singlet States

Abstract From the differences in electronic structure of 5-halogenated uracil derivatives and thymine there is discussed the connection with different radiosensibilization. At the same time the calculated energy change of the second and third excited singlet states for the particularly sensibilizating substances 5-bromo-uracil and 5-iodo-uracil compared with the remaining uracil derivatives is remarkable. In connection with different charge distribution this difference in principle may cause different energy transport processes. The very phenomenon is to be mentioned which has been discussed in previous papers dealing with the different carcinogenic molecules 3,4-benzpyrene and 1,2-benzpyrene.

LATTICE BOLTZMANN SIMULATION OF MOMENTUM AND ENERGY TRANSFER IN A POROUS MEDIUM

2005 ◽  
Vol 19 (28n29) ◽  
pp. 1531-1534 ◽  
Author(s):  
YOUSHENG XU ◽  
YANG LIU ◽  
GUOXIANG HUANG
Keyword(s):  
Porous Medium ◽  
Energy Transfer ◽  
Lattice Boltzmann ◽  
Energy Transport ◽  
Transport Processes ◽  
Air Conditioning System ◽  
Flow And Heat Transfer ◽  
Lattice Boltzmann Simulation ◽  
Darcy Equations ◽  
Boltzmann Method

The fluid flow and heat transfer in porous media has wide applications in oil industry and air conditioning system. In this study the momentum and energy transport processes in a porous medium are numerically simulated. The Brinkman-Forchheimer-extended Darcy equations and energy equation are solved using single lattice-Boltzmann method (LBM). As a first attempt, a benchmark problem is studied, i.e., momentum and energy transfer in a rectangular enclosure with differentially heated vertical walls. The effect of permeability on the critical Rayleigh numbers, the temperature distribution and flow field is discussed.

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