Cationic surfactant (CS+) in urban river water and sediment was extracted and determined spectrophotometrically with 2 membrane filters. The CS+ in the water samples, mostly in the form of an ion associate with the coexisting anionic surfactant (AS), was collected on a polytetrafluoroethylene (PTFE) membrane filter and eluted with methanol. Bromphenol blue (BPB), hydrochloric acid, and water we...

A cationic surfactant-selective electrode for sensitive analysis of cationic surfactant has been developed by using a plasticized poly (vinyl chloride) membrane based on nanocomposite cation exchanger polypyrrole zirconium titanium phosphate. The electrode is excellently selective for the cetyl trimethyl ammonium bromide (CTAB) ion over inorganic ions and other cationic surfactants. The membran...

We describe the experimental investigation of time-resolved magnetic field effects in exciplex-forming organic donor-acceptor systems. In these systems, the photoexcited acceptor state is predominantly deactivated by bimolecular electron transfer reactions (yielding radical ion pairs) or by direct exciplex formation. The delayed fluorescence emitted by the exciplex is magnetosensitive if the re...

Although the role of methanesulfonic acid (HMSA) in particle formation in the gas phase has been extensively studied, the details of the HMSA-induced ion pair particle formation at the air-water interface are yet to be examined. In this work, we have performed Born-Oppenheimer molecular dynamics simulations and density functional theory calculations to investigate the ion pair particle formatio...

Using Solvent Evaporating and Atomic Emission Spectrophotometric methods, the solubility of Li2CO3 in waterat 25°C was determined. Comparing the value of thermodynamic solubility product constant, Ksp(th),(Ksp(tn) = exp(—AG.ss/RT)) of the mentioned salt to the value which is obtained from the observed solubility,shnolL-1 , and activity coefficients, f+ and f, which are estimated upon the extend...

The influence of the alkali resistant surfactant Dowfax 2A1 on single ion track etching in 30 lm polycarbonate foils is studied at low etch rate (5 M NaOH at 41.5 ± 2 C) using electro conductivity measurements. At surfactant concentrations above 10 4 vol.% breakthrough times are predictable (Dt/t < 0.25). At high surfactant concentrations (P0.1 vol.%) the formation of cylindrical channels is fa...

Lamellar bodies, an intracellular source of lung alveolar surfactant, were isolated from rat lung homogenates and studied in the Langmuir-Adams surface balance. By layering intact lamellar bodies on the surface of a more dense sucrose subphase, we studied the factors affecting film formation from surface tension-vs-time data and determined surface tension-surface area isotherms by compression a...