Stability of transport processes in continuous media with heat or material sources and sinks

1978 ◽  
Vol 35 (2) ◽  
pp. 979-981
Author(s):  
P. P. Lazarev ◽  
A. S. Pleshanov
Keyword(s):  
Continuous Media ◽  
Transport Processes ◽  
Sources And Sinks ◽  
Material Sources

scholarly journals Environmental release, fate and ecotoxicological effects of manufactured ceria nanomaterials

2014 ◽  
Vol 1 (6) ◽  
pp. 533-548 ◽  
Author(s):  
Blanche Collin ◽  
Mélanie Auffan ◽  
Andrew C. Johnson ◽  
Inder Kaur ◽  
Arturo A. Keller ◽  
...  
Keyword(s):  
Critical Review ◽  
Fate And Transport ◽  
Transport Processes ◽  
Characterization Methods ◽  
Sources And Sinks ◽  
Ecotoxicological Effects ◽  
Environment Detection ◽  
Soil And Water

This critical review presents the sources and sinks of nanoceria in the environment, detection and characterization methods, fate and transport processes, toxicity and likelihood of toxicity in soil and water.

Characterizing Material Sources and Sinks.

1992 ◽  
Vol 641 (1 Sources of In) ◽  
pp. 63-78 ◽  
Author(s):  
BRUCE A. TICHENOR
Keyword(s):  
Sources And Sinks ◽  
Material Sources

SPATIOTEMPORAL STRUCTURES IN DISCRETELY-COUPLED ARRAYS OF NONLINEAR CIRCUITS: A REVIEW

1995 ◽  
Vol 05 (01) ◽  
pp. 17-50 ◽  
Author(s):  
A.P. MUÑUZURI ◽  
V. PÉREZ-MUÑUZURI ◽  
M. GÓMEZ-GESTEIRA ◽  
L.O. CHUA ◽  
V. PÉREZ-VILLAR
Keyword(s):  
Wave Propagation ◽  
Pattern Formation ◽  
Spatial Organization ◽  
Nonlinear Dynamical Systems ◽  
Spiral Wave ◽  
Continuous Media ◽  
Transport Processes ◽  
Coupled Systems ◽  
Spatiotemporal Pattern ◽  
Characteristic Time Scale

Spatiotemporal pattern formation occurring in discretely-coupled nonlinear dynamical systems has been studied numerically. Reaction-diffusion systems can be viewed as an assembly of a large number of identical local subsystems which are coupled to each other by diffusion. Here, the local subsystems are defined by a system of nonlinear ordinary differential equations. While for continuous systems, the characteristic time scale corresponding to the diffusion is slower than that corresponding to the local subsystems, in discretely-coupled systems, both time scales can be of the same order of magnitude. Discrete systems can exhibit behaviors different from those exhibited by their equivalent continuous model: the wave propagation failure phenomenon occurring in nerve-pulse propagation due to transmission blockage is a case in point. In this case, it is found that the wave fails to propagate at or below some critical value of the coupling coefficient. Systems of coupled cells can be found to occur in the transformation and transport processes in living cells, tissues, neuron networks, physiological systems and ecosystems, as well as in all forms of chemical, biochemical reactors and combustion systems. In this paper, we review the possibilities of using arrays of discretely-coupled nonlinear electronic circuits to study these systems. The possibility of building large arrays of these circuits via VLSI technology makes this approach a unique tool for real time applications. Classical examples occurring in other continuous media, such as spiral wave initiation and propagation, and Turing pattern formation, are depicted here. Because of the discrete nature of our system, the influence of inhomogeneities arising from damaged cells, or from an anisotropic media, is analyzed for spiral wave propagation. Spiral wave initiation and vulnerability effects are considered and compared with their corresponding effects in continuous media. More complex spatiotemporal structures are also studied via three-dimensional arrays of discretely-coupled circuits. Straight and twisted scroll waves, as well as scroll ring waves, are shown to exist in these arrays, where their properties can be easily measured. Sidewall forcing of Turing patterns is shown to be capable of driving the system into a perfect spatial organization, namely, a rhombic pattern, where no defects occur. The dynamics of the two layers supporting Turing and Hopf modes, respectively, is analyzed as a function of the coupling strength between them. The competition between these two modes is shown to increase with the diffusion between layers.

Saturn's E, G and F rings: modulated by the plasma sheet

1984 ◽  
Vol 75 ◽  
pp. 597
Author(s):  
E. Grün ◽  
G.E. Morfill ◽  
T.V. Johnson ◽  
G.H. Schwehm
Keyword(s):  
Solar Wind ◽  
Direct Contact ◽  
Transport Processes ◽  
Time Variable ◽  
Dust Particles ◽  
Spatial Diffusion ◽  
Drag Forces ◽  
Orbit Perturbation ◽  
Time Variations ◽  
F Ring

ABSTRACTSaturn's broad E ring, the narrow G ring and the structured and apparently time variable F ring(s), contain many micron and sub-micron sized particles, which make up the “visible” component. These rings (or ring systems) are in direct contact with magnetospheric plasma. Fluctuations in the plasma density and/or mean energy, due to magnetospheric and solar wind processes, may induce stochastic charge variations on the dust particles, which in turn lead to an orbit perturbation and spatial diffusion. It is suggested that the extent of the E ring and the braided, kinky structure of certain portions of the F rings as well as possible time variations are a result of plasma induced electromagnetic perturbations and drag forces. The G ring, in this scenario, requires some form of shepherding and should be akin to the F ring in structure. Sputtering of micron-sized dust particles in the E ring by magnetospheric ions yields lifetimes of 102to 104years. This effect as well as the plasma induced transport processes require an active source for the E ring, probably Enceladus.

TRANSPORT PROCESSES IN GLASS

1982 ◽  
Vol 43 (C9) ◽  
pp. C9-369-C9-380 ◽  
Author(s):  
A. R. Cooper ◽  
Jr
Keyword(s):  
Transport Processes

Revisiting the passivation of stainless steels and other passive CRAs

2018 ◽  
Vol 106 (1) ◽  
pp. 107 ◽  
Author(s):  
Jean- Louis Crolet
Keyword(s):  
Electrical Conductivity ◽  
Metal Ions ◽  
Base Metal ◽  
Stainless Steels ◽  
Electronic Conductivity ◽  
Transport Processes ◽  
General Knowledge ◽  
Inorganic Polymers ◽  
Faraday Cage

All that was said so far about passivity and passivation was indeed based on electrochemical prejudgments, and all based on unverified postulates. However, due the authors’ fame and for lack of anything better, the great many contradictions were carefully ignored. However, when resuming from raw experimental facts and the present general knowledge, it now appears that passivation always begins by the precipitation of a metallic hydroxide gel. Therefore, all the protectiveness mechanisms already known for porous corrosion layers apply, so that this outstanding protectiveness is indeed governed by the chemistry of transport processes throughout the entrapped water. For Al type passivation, the base metal ions only have deep and complete electronic shells, which precludes any electronic conductivity. Then protectiveness can only arise from gel thickening and densification. For Fe type passivation, an incomplete shell of superficial 3d electrons allows an early metallic or semimetallic conductivity in the gel skeleton, at the onset of the very first perfectly ordered inorganic polymers (- MII-O-MIII-O-)n. Then all depends on the acquisition, maintenance or loss of a sufficient electrical conductivity in this Faraday cage. But for both types of passive layers, all the known features can be explained by the chemistry of transport processes, with neither exception nor contradiction.

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