Isotropic magnetic field modulations cause the formation and coarsening of transient two dimensional paramagnetic colloidal networks. We show that the virgin transient network consists of sub- and supercritical meshes. In the initial coarsening process subcritical meshes shrink while supercritical meshes grow. While the coarsening is a truly non-equilibrium process, the critical nucleation size...

The use of polymers in the modern pharmaceutical industry is quite wide and needs a lot of different information. One of the more recent applications is the impregnation of a polymeric system with a drug using as carrier a supercritical fluid. This process is based on dissolving the active principle in a supercritical fluid, the supercritical solvent swells and reduces the glass transition temp...

The objective of this work is to track the amount of metal complexes distributed in the extraction cell, collection vial, and tubing used in supercritical fluid extraction (SFE) systems after progressive removal of metal ions in supercritical carbon dioxide (SC-CO2). Sodium diethyldithiocarbamate (NaDDC) and dibutylammonium dibutyldithiocarbamate (DBDC) ligands were used to form complexes with ...

We compare the methods of continuous solvent (Soxhlet) and supercritical solvent extractions for the removal of the organic template from nanostructured silica monoliths. Our monoliths are formed by templating the L3 liquid crystal phase of cetylpyridinium chloride in aqueous solutions with tetramethoxy silane. The monoliths that result from both Soxhlet and supercritical extraction methods are...

Supercritical fluids are a unique class of nonaqueous media in which biocatalytic reactions can occur. The physical properties of supercritical fluids, which include gas-like diffusivities and liquid-like densities, can be predictably controlled with changing pressure. This paper describes how adjustment of pressure, with the subsequent predictable changes of the dielectric constant and Hildebr...

Supercritical fluids (SCF) are very interesting solvents with unique properties, such as high solute diffusivities, low viscosity and density values similar to liquids. All these features can be tuned with modifications in the pressure or temperature or the addition of modifiers [1]. Supercritical CO2 (sc-CO2) is one of the most promising alternative solvents because it is cheap, abundant, non-...

We study bifurcations associated with stability of the lowest stationary point (SP) of a damped parametrically forced pendulum by varying ω0 (the natural frequency of the pendulum) and A (the amplitude of the external driving force). As A is increased, the SP will restabilize after its instability, destabilize again, and so ad infinitum for any given ω0. Its destabilizations (restabilizations) ...

This paper proposes a new type of solar energy based power generation system using supercritical carbon dioxide and heat storage. The power generation cycle uses supercritical carbon dioxide as the working fluid and integrates the supercritical carbon dioxide cycle with an efficient high-temperature heat storage. The analysis shows that the new power generation system has significantly higher s...

Herein we report a novel method for the synthesis and processing of molecular recognition materials using supercritical fluid technology. Semi-covalently imprinted polymers with adsorption affinity to bisphenol A (BPA) were prepared for the first time in scCO2, at 65 oC and 21 MPa. BPA hydrolysis from the polymeric matrix was also performed in supercritical environment using a specific cleavage...