[1] We show how to predict flow properties for a variety of porous media using pore-scale modeling with geologically realistic networks. Starting with a network representation of Berea sandstone, the pore size distribution is adjusted to match capillary pressure for different media, keeping the rank order of pore sizes and the network topology fixed. Then predictions of single and multiphase pr...

Organotins present a toxicological risk to biota in the aquatic environment. Understanding the behaviour of these compounds in sediment is challenging, with sophisticated analytical techniques required for their measurement. We investigated the use of silica-bound sorbents for diffusive gradients in thin-films (DGT) adsorption gels to pre-concentrate five organotins (monobutlytin (MBT), dibutyl...

biochar and activated carbon, as carbon-rich porous materials, have wide environmental applications. in the present research, rice husk (rh) was used for preparation of biochar at 400, 600, and 800 °c under simple pyrolysis, physically-activated carbon with water steam, chemically-activated carbon with potassium hydroxide (koh), and physiochemically-activated carbon with koh and steam. physical...

Soil micromorphology was applied to specify flow domains in different soils and to select a suitable numerical model for simulation of water flow and herbicide transport. Pore structure detected on soil micromorphological images represented in all cases domains of prevailing water flow and solute transport. Depending on pore configuration and boundary conditions either water immobilization or p...

We investigated the structural and energetic determinants underlying water permeation through peptidic nanopores, motivated by recent experimental findings that indicate that water mobility in single-file water channels displays nonlinear length dependence. To address the molecular mechanism determining the observed length dependence, we studied water permeability in a series of designed gramic...

Vibrio parahaemolyticus, a species that includes strains known to be pathogenic in humans, and other Vibrionaceae are common, naturally occurring bacteria in coastal environments. Understanding the ecology and transport of these organisms within estuarine systems is fundamental to predicting outbreaks of pathogenic strains. Infaunal burrows serve as conduits for increased transport of tidal wat...

The gas diffusion layer (GDL) is an essential element of the electrodes in polymer electrolyte membrane (PEM) fuel cells. The GDL makes electrical contact with the catalyst layers to provide a larger area to carry the electronic current from the catalyst to the bipolar plates reducing the resistance for current flow. The GDL must be porous to permit the flow of reactant gas from the gas flow ch...

Several contrasting uses of the terms macro(large) and micro(small) pore can be identified in soil science literature. In some cases macropores are (i) considered to be pores > 15 (Marshall, 1959) or 100 /im in diam (Bouma et al., 1977) or (ii) implied to be even larger when described in terms of wormholes (Ehlers, 1975), root channels (Aubertin, 1971). and shrinkage cracks (Lewis, 1977). The s...

We have employed atomic-scale molecular dynamics simulations to address ion leakage through transient water pores in protein-free phospholipid membranes. Our results for phospholipid membranes in aqueous solution with NaCl and KCl salts show that the formation of transient water pores and the consequent ion leakage can be induced and be driven by a transmembrane ionic charge imbalance, an inher...

Ligands usually bind to proteins by displacing water from the binding site. The affinity and kinetics of binding therefore depend on the hydration characteristics of the site. Here, we show that the extreme case of a completely dehydrated free binding site is realized for the large nonpolar binding cavity in bovine beta-lactoglobulin. Because spatially delocalized water molecules may escape det...