Pharmaceutical Formulation Facilities as Sources of Opioids and Other Pharmaceuticals to Wastewater Treatment Plant Effluents

Facilities involved in the manufacture of pharmaceutical products are an under-investigated source of pharmaceuticals to the environment. Between 2004 and 2009, 35 to 38 effluent samples were collected from each of three wastewater treatment plants (WWTPs) in New York and analyzed for seven pharmaceuticals including opioids and muscle relaxants. Two WWTPs (NY2 and NY3) receive substantial flows (>20% of plant flow) from pharmaceutical formulation facilities (PFF) and one (NY1) receives no PFF flow. Samples of effluents from 23 WWTPs across the United States were analyzed once for these pharmaceuticals as part of a national survey. Maximum pharmaceutical effluent concentrations for the national survey and NY1 effluent samples were generally <1 μg/L. Four pharmaceuticals (methadone, oxycodone, butalbital, and metaxalone) in samples of NY3 effluent had median concentrations ranging from 3.4 to >400 μg/L. Maximum concentrations of oxycodone (1700 μg/L) and metaxalone (3800 μg/L) in samples from NY3 effluent exceeded 1000 μg/L. Three pharmaceuticals (butalbital, carisoprodol, and oxycodone) in samples of NY2 effluent had median concentrations ranging from 2 to 11 μg/L. These findings suggest that current manufacturing practices at these PFFs can result in pharmaceuticals concentrations from 10 to 1000 times higher than those typically found in WWTP effluents

Droplets on liquids and their journey into equilibrium

The morphological path of droplets on a liquid substrate towards equilibrium is investigated experimentally and theoretically. The droplets emerge in the late stage of a dewetting process of short chained polystyrene (PS) dewetting from liquid polymethyl-methacrylate (PMMA). The three-dimensional droplet profiles are obtained experimentally by combining the in situ imaged PS/air interface during equilibration and the ex situ imaged PS/PMMA interface after removal of the PS by a selective solvent. Numerically the transient drop shapes are calculated by solving the thin-film equation in lubrication approximation using the experimentally determined input parameter like viscosity, film thickness and surface tensions. The numerically obtained droplet morphologies and time scales agree very well with the experimental drop shapes. An unexpected observation is that droplets with identical volumes synchronise their motion and become independent of the initial geometry long time before equilibrium is reached

Interface morphologies in liquid/liquid dewetting

The dynamics and morphology of a liquid polystyrene (PS) film on the scale of a hundred nanometer dewetting from a liquid polymethylmethacrylate (PMMA) film is investigated experimentally and theoretically. The polymers considered here are both below their entanglement lengths and have negligible elastic properties. A theoretical model based on viscous Newtonian flow for both polymers is set up from which a system of coupled lubrication equations is derived and solved numerically. A direct comparison of the numerical solution with the experimental findings for the characteristic signatures of the cross-sections of liquid/air and liquid/liquid phase boundaries of the dewetting rims as well as the dewetting rates is performed and discussed for various viscosity ratios of the PS and PMMA layers

Conductivity in nonpolar media: experimental and numerical studies on sodium AOT-hexadecane, lecithin-hexadecane and aluminum(III)-3,5-diisopropyl salicylate-hexadecane systems.

The conductivity behavior of doped hydrocarbon systems is studied by applying impedance spectroscopy. In the case of 3,5-diisopropyl salicylato aluminum (III) the charge carriers are formed by dissociation of the compound and their concentration is proportional to the square root of the solute concentration. In hydrocarbon systems that consist of micelle forming compounds (sodium AOT/ lecithin) a linear dependence of charge carrier concentration on solute concentration is observed in the concentration regime where micelles are present. The conduction mechanisms are studied by numerical solution of a Poisson-Nernst-Planck system that describes the charge transport. We follow two different approaches to extract the degree of micelle dissociation from the impedance data. Firstly, by computing the response of a linear approximation of the Poisson-Nernst-Planck model, and secondly by computing the fully nonlinear response from direct numerical simulations using finite elements. For high and moderate frequencies both approaches agree very well with the experimental data. For small frequencies the response becomes nonlinear and the concept of impedance fails. Furthermore, the numerically computed values for the degree of dissociation are of the same order of magnitude as the values obtained with classical formulas, but still differ by a factor of about 1/3. The direct numerical simulation allows new insight into the conduction mechanisms for different frequency regimes

Vortex imaging by low-temperature scanning electron microscopy and correlation with low-frequency noise in YBCO SQUIDs

We present a technique for direct imaging of magnetic flux quanta trapped in direct current (DC) superconducting quantum interference devices (SQUIDs) which consist either of washers patterned in single YBa2Cu3O7-delta (YBCO) films or which are patterned in multilayer structures from YBCO/SrTiO3/YBCO thin films. Simultaneously, we are able to measure the low-frequency noise of our devices under test, which allows correlation of the local distribution of vortices with low-frequency noise in the SQUIDs. The vortex imaging and noise measurements are performed with the SQUIDs mounted on a liquid nitrogen cooled cryostage of a scanning electron microscope (SEM) for investigation at variable temperature (77 K < T< T-c) and in controllable magnetic fields up to several hundred mu T Our imagine technique, which yields a spatial resolution of about 1 mu m, is based on the electron-beam-induce local displacement Delta r of vortices, which is detected as a flux change Delta Phi = Delta r(partial derivative Phi/partial derivative r) in the SQUID loop. Hence, the signal amplitude provides direct information on the coupling strength partial derivative Phi/partial derivative r. since partial derivative Phi/partial derivative r determines the amount of flux noise which a fluctuating vortex induces in the SQUID, we obtain valuable information on possible low-frequency noise sources in the SQUIDs, We investigated washer SQUIDs with regular arrays of micron-sized holes (antidots) to image the compering formation of multiquanta trapped in antidots vs. the formation of interstitial vortices. In most cases, the interstitial vortices are pinned reproducibly at the same locations. These pinning sites do not correlate with the surface morphology of the films. (C) 2000 Elsevier Science B.V. All rights reserved