The determination of the fate of aircraft de-icing fluids in near runway soils is important in evaluating environmental impacts and in the design of treatment system. The effect of biodegradation of the primary component of de-icing fluids, propylene glycol (PG), was tested in waters-saturated sand columns. Biogrowth significantly reduced the hydraulic conductivity of the sand. This change in h...

We report the first time-resolved fluorescence emission spectra and time-resolved fluorescence anisotropies obtained using frequency-domain fluorescence spectroscopy. We examined the fluorophore p-2-toluidinyl-6-naphthalenesulfonic acid (TNS) in viscous solvents and bound to the heme site of apomyoglobin using multifrequency phase fluorometers. Fluorescence phase shift and modulation data were ...

The issues of waste generation in batch process plants differ in many aspects from those in continuous plants. Despite the smaller-scale of processing, complexities from discontinuities and run-to-run variations make waste minimization in batch plants more challenging. In this paper, we introduce an integrated qualitative-quantitative methodology and decision support system, called Batch-ENVOPE...

Este trabalho estuda o fluxo de etileno glicol (MEG) sobre duas superfícies sólidas com constituições químicas diferentes: borossilicato e dióxido de estanho (SnO2). O alinhamento intermolecular, determinado como polarização e anisotropia, mostrou dependência da natureza química do sólido. A razão entre as tensões interfaciais dinâmicas foi 1.09 ± 0.07, devendo ser maior para MEG/borossilicato ...

Leading commercial electronic cigarettes were tested to determine bulk composition. The e-cigarettes and conventional cigarettes were evaluated using machine-puffing to compare nicotine delivery and relative yields of chemical constituents. The e-liquids tested were found to contain humectants, glycerin and/or propylene glycol, (⩾75% content); water (<20%); nicotine (approximately 2%); and flav...

Two injectable forms of temazepam, in 90% propylene glycol or 40% salicylic acid, were studied in volunteers, and before surgery in healthy patients. The volunteers also received two forms (capsule and elixir) by mouth. The salicylate preparation was painful on injection and both i.v. formulations caused an unacceptably high incidence of venous thrombosis. Temazepam was detected in plasma earli...

It is a neutral white crystalline substance with a bitter taste and is stable in neutral and acid solutions. The drug is moderately soluble in water (0.25 per cent at room temperature, 0.65 per cent at 700 C and up to 15 per cent in propylene glycol, 5 per cent in 50 per cent acetamide), and is insoluble in vegetable oils. Solubility in urine or serum is about the same as in water. Solutions ar...

We have previously established that the relative concentrations of propylene glycol and ethanol as a binary solvent system have a significant effect on the skin penetration of 2% solutions of minoxidil at 50 microL/cm2. The present work extends these studies and investigates the penetration of minoxidil from the different vehicle combinations as functions of application volume and occlusion. De...

This work evaluated the occlusive versus non-occlusive application of microemulsion (ME) for the transdermal delivery of progesterone. The mechanisms of enhanced skin penetration were investigated. ME comprised of oleic acid, Tween 80, propylene glycol, and water, was used neat or with ethanol as a volatile cosurfactant. The ME formulations enhanced progesterone transdermal flux compared to the...