We have developed a methodology that can be used to determine disjoining pressures (Π) in both stable and unstable wetting films from the spatial and temporal profiles of dynamic wetting films. The results show that wetting films drain initially by the capillary pressure created by the changes in curvature at the air/water interface and subsequently by the disjoining pressure created by surface...

Bubbles in the ocular tear film have been observed following both dry-chamber, simulated compressed air dives and in-water, recreational compressed air dives. The current paper reports on the formation of tear film bubbles in a breath-hold diver following repeated, extended breath-hold excursions to a maximum depth of -28.5 m. It is believed that this is the first time that ocular tear film bub...

Pullulan, a water soluble, bioadhesive and biocompatible biopolymer is used as an efficient matrix for enalapril maleate film preparation. The obtained film contains as much as 67% of enalapril maleate, relative to the initial amount used for experiments. The drug content was evaluated by using 1 H-NMR and UV-vis spectroscopy. The pullulanenalaprilmaleate blends exhibit good physicochemical pro...

Purpose: A simple method for verifying the dose point kernel of Ir-192 source used in HDR brachytherapy using Kodak EDR2 film in a spiralphantom. Method and Materials: A spiral solid water phantom availablefrom Gammex International for IMRT QA was modified for this study. A CT scan image of the phantom was acquired with a 10 x 12 inch filmloaded in the spiral groove. A 3.5 mm long 8...

In a previous study, the morphology of water-plasticised polyacrylonitrile (PAN) film, made by compression moulding moist polymer powder, was discussed. The X-ray diffraction pattern of the plasticised film was different from that of dry PAN and this led to the suggestion that hydrated polymer crystallites had been formed by a portion of the water. The location of the remainder of the water was...

This paper uses Monte Carlo simulations to calculate the Spencer-Attix water/medium stopping-power ratios (sw, med) for the dosimetry of scanned proton pencil beams. It includes proton energies from 30 to 350 MeV and typical detection materials such as air (ionization chambers), radiochromic film, gadolinium oxysulfide (scintillating screens), silicon and lithium fluoride. Track-ends and partic...

All surfaces exposed to ambient conditions are covered by a thin film of water. Other than at high humidity conditions, i.e., relative humidity higher than 80%, those water films have nanoscale thickness. Nevertheless, even the thinnest film can profoundly affect the physical and chemical properties of the substrate. Information on the structure of these water films can be obtained from spectro...

Ultrathin glycine-water ice films have been prepared in ultrahigh vacuum by condensation of H(2)O and glycine at 90 K on single crystalline alumina surfaces and processed by soft x-ray (610 eV) exposure for up to 60 min. The physicochemical changes in the films were monitored using synchrotron x-ray photoemission spectroscopy. Two films with different amounts of H(2)O have been considered in or...

The salt-water interface is one of the most important and common on earth, playing a prominent role in disciplines such as atmospheric science and biology. Despite the apparent simplicity of such interfaces, arguably the most fundamental question of what the nature and structure of the liquid water/salt interface is under ambient conditions remains unclear. Here we address this issue with an ab...

We report a free energy calculation of a methane molecule as a function of its position along the normal to the water surface, and establish that the formation of a methane film at the water surface is thermodynamically favoured.