SIMULATION OF REACTIVE GEOCHEMICAL TRANSPORT PROCESSES IN CONTAMINATED AQUIFERS USING SURROGATE MODELS

2015 ◽  
Author(s):  
Hamed Koohpayehzadeh Esfahani
Keyword(s):  
Surrogate Models ◽  
Transport Processes ◽  
Contaminated Aquifers ◽  
Geochemical Transport

Positron emission tomography for modelling of geochemical transport processes in clay

2005 ◽  
Vol 93 (9-10) ◽  
Author(s):  
Michael Richter ◽  
Marion Gründig ◽  
Klaus Zieger ◽  
Anita Seese ◽  
Osama Sabri
Keyword(s):  
Positron Emission Tomography ◽  
Transport Processes ◽  
Experimental Device ◽  
Emission Tomography ◽  
Clay Rock ◽  
Salt Solutions ◽  
Positron Emission ◽  
Unsaturated Clay ◽  
Geochemical Transport

SummaryThe transport of water and salt solutions in unsaturated clay and clay rock was measured using the positron emission tomography (PET). The experimental device is described. KF marked with

Tomographic radiotracer studies of the spatial distribution of heterogeneous geochemical transport processes

2007 ◽  
Vol 22 (11) ◽  
pp. 2334-2343 ◽  
Author(s):  
Marion Gründig ◽  
Michael Richter ◽  
Anita Seese ◽  
Osama Sabri
Keyword(s):  
Spatial Distribution ◽  
Transport Processes ◽  
Geochemical Transport

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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