The affinity of the excess proton for the aqueous solution-hydrophobic interface was examined for two specific examples, the air-water and hydrophobic wall-water cases, using a multiconfigurational molecular dynamics algorithm. The use of a reactive simulation method is important as it allows for a realistic description of the excess proton, namely, its propensity to hop between water molecules...

We have previously investigated the formation of water-CO2 interface by means of a drop tensiometer [1]. In presence of CO2 , the interaction between the two adjacent phases leads to an organization of interfacial cluster network which controls the tension and the mechanical properties of the interface. The formation of those clusters at CO2 pressure lower than 80 bar inhibits the adsorption of...

Models on flow and transport in surface water sediments currently neglect compaction, although it is well understood that compaction is one of the major processes below the free fluid-sediment interface. Porosity changes in the sediment layers, as a result of compaction, are measured in almost all probes: porosity decreases with the distance from the surface water-sediment interface. This paper...

The interface-selective second harmonic generation (SHG) nonlinear optical spectroscopy and the surface tension method have been used to measure the effect of electrolyte on the adsorption isotherm of 4-hydroxyacetophenone (4-HA) at the air-solution interface. It was observed that high NaCl concentration favors adsorption of organic molecules to the air-solution interface. Measurements of the p...

A method for direct visualization of the position of nanoscale colloidal particles at air-water interfaces is presented. After assembling hard (polystyrene, poly(methyl methacrylate), silica) or soft core-shell gold-hydrogel composite (Au@PNiPAAm) colloids at the air-water interface, butylcyanoacrylate is introduced to the interface via the gas phase. Upon contact with water, an anionic polymer...

We have devised a method of making a flat oil/water interface which remains flat on inversion. Cell adhesion to the interface can be observed microscopically. Glutaraldehyde-fixed human red blood cells adhere to the interface between physiological saline and hexadecane containing surface-active behenic acid at pH values below about 7-5. At high pH values, cells are prevented from adhering due t...

We calculate the second-order streaming force in a fluid in the vicinity of the solid/fluid interface for two systems of importance in the technology of megasonic cleaning of silicon wafers. The first system consists of a single planar interface between a solid elastic medium representing silicon and a viscous fluid, namely water. The second system accounts for the finite thickness of silicon w...

The ultrafast solvation dynamics of courmarin 314 (C314) molecules at the air/water interface has been shown to depend on their orientation with respect to the plane of the interface. A pump/second harmonic probe method using femtosecond laser pulses were used to measure the interface solvation dynamics. The pump light was S polarized, i.e., in the interface plane, or P polarized, i.e., in the ...

Reactive mineral-water interfaces exert control on the bioavailability of contaminant arsenic species in natural aqueous systems. However, the ability to accurately predict As surface complexation is limited by the lack of molecular-level understanding of As-water-mineral interactions. In the present study, we report the structures and properties of the adsorption complexes of arsenous acid (As...

The present study demonstrates a methodology for optimization of environmental data acquisition. Based on the premise that the worth of data increases in proportion to its ability to reduce the uncertainty of key model predictions, the methodology can be used to compare the worth of different data types, gathered at different locations within study areas of arbitrary complexity. The method is a...