An ion-pair high performance liquid chromatographic method was developed for the simultaneous determination of p-aminosalicylic acid (PAS) and its degradation product m-aminophenol (MAP) in a newly developed multiparticular drug delivery system. Owing to the concentration differences of PAS and MAP, acetanilide and sulfanilic acid were used as internal standards, respectively. The separation wa...

Abstract Previously performed experiments on flow through an ordered porous media cell with tomographic particle image velocimetry reveal a complex three-dimensional steady-state pattern. This pattern emerge in the region where inertial structures have been previously reported for wide range of packings. The onset these is here scrutinized three different types packing using finite difference m...

We present a comprehensive computational study of the short-time transport properties of bidisperse hard-sphere colloidal suspensions and the corresponding porous media. Our study covers bidisperse particle size ratios up to 4 and total volume fractions up to and beyond the monodisperse hard-sphere close packing limit. The many-body hydrodynamic interactions are computed using conventional Stok...

[1] We simulate two-fluid-phase flow at the pore scale using a lattice Boltzmann (LB) approach. Using a parallel processing version of the Shan-Chen model that we developed, we simulate a set of ideal two-fluid systems and a model two-fluid-phase porous medium system comprised of a synthetic packing with a relatively uniform distribution of spheres. We use the set of ideal two-phase systems to ...

From application perspectives in adsorption, activated carbon fiber (ACF) is by far one of the most important carbon nanoporous materials to be considered. It has great advantages over other commercial porous storage materials. Activated carbon fiber (ACF) is a promising microporous material with a fiber shape and well-defined porous structure. In general, production of ACF can be commercially ...

This paper investigates the impact of the irregular microgeometry of polyurethane acoustic foam on the macroscopic acoustic behavior predicted by a unit-cell model. Two semi-empirical unit-cell models coupled to a rigorous sensitivity analysis technique are used for this purpose. In these models, the porous material is idealized as a packing of a periodic unit-cell (PUC) representative of the d...

Bacterial chemotaxis enables motile cells to move along chemical gradients and to swim toward optimal places for biodegradation. However, its potentially positive effects on subsurface remediation rely on the efficiency of bacterial movement in porous media, which is often restricted by high deposition rates and adhesion to soil surfaces. In well-controlled column systems, we assessed the influ...

We explore a mean-field theory of fluid imbibition and drainage through permeable porous solids. In the limit of vanishing inertial and viscous forces, the theory predicts the hysteretic "retention curves" relating the capillary pressure applied across a connected domain to its degree of saturation in wetting fluid in terms of known surface energies and void space geometry. To avoid complicated...

Six homochiral coordination polymers 1-6 based on an enantiopure elongated and bent bipyridine ligand were synthesized and characterized by single-crystal X-ray diffraction studies. The framework structures of all six compounds were built up from similar 1D polymeric chains composed of 46-membered metallomacrocycles. Four distinct packing patterns were observed for this family of coordination p...

Low-cost antireflection coatings (ARCs) on large optical surfaces are an ingredient-technology for high-performance solar cells. While nanoporous thin films that meet the zero-reflectance conditions on transparent substrates can be cheaply manufactured, their suitability for outdoor applications is limited by the lack of robustness and cleanability. Here, we present a simple method for the manu...