We explore the dynamical restrictions on the structure of dark matter halos through a study of cosmological self-similar gravitational collapse solutions. A fluid approach to the collisionless dynamics of dark matter is developed and the resulting closed set of moment equations are solved numerically including the effect of halo velocity dispersions (both radial and tangential), for a range of ...

The graphene oxide (GO) is widely used as a graphene precursor. It has been recently evidenced that this object can form different lyotropic liquid crystals phases observed in highly anisotropic colloids. The confinement of GO sheets, a two-dimensional (2D) crystal is herein aim of study. The binary GO water is studied to describe the liquid crystallinity of concentrated dispersions, characteri...

In the present study solid dispersions of the antifungal drug Ketoconazole were prepared with Pluronic F-127 and PVP K-30 with an intention to improve its dissolution properties. Investigations of the properties of the dispersions were performed using release studies, Differential scanning calorimetery (DSC), X-ray powder diffraction (XRD) and Fourier transform infrared (FTIR). The results obta...

Improvement on the stability and loading of unfunctionalized single wall carbon nanotubes (SWNTs) in amide solvents is necessary to enhance the performances of SWNT-polymer composites used for optical applications (e.g., as non-linear saturable absorbers). We show that polyvinylpyrrolidone (PVP) can not only increase the stability of ultrasonically dispersed HiPco SWNTs in pure N-methyl-2pyrrol...

Objective Solid dispersions of daidzein (DZ) were prepared using tween-80 as the surfactant to improve its dissolution and solubility. Methods Using tween-80 as the surfactant and polyethylene glycol (PEG)-10000 as the carrier, solid dispersions of DZ were prepared by solvent method. Infrared spectroscopy (IR) and X-ray diffraction spectroscopy were applied to determine the status of DZ in carr...

A method is demonstrated to prepare graphene dispersions at high concentrations, up to 1.2 mg mL(-1), with yields of up to 4 wt% monolayers. This process relies on low-power sonication for long times, up to 460 h. Transmission electron microscopy shows the sonication to reduce the flake size, with flake dimensions scaling as t(-1/2). However, the mean flake length remains above 1 microm for all...

Instability in film coating formulations can arise from interactions between aluminum lake pigments and aqueous polymeric dispersions. The purpose of this study was to characterize the interactions between three polymethacrylate-based aqueous polymeric dispersions (Eudragit RS 30 D, Eudragit L 30 D-55, and Eudragit NE 30 D) and aluminum lakes. Particle size measurements, pH stability profiles, ...

Catalytic polymerization of ethylene in aqueous emulsion by in situ catalysts based entirely on compounds commercially available from standard chemicals suppliers, namely a chlorinated derivative of 1,4-benzoquinone, triphenylphosphine, and bis(1,5-cyclooctadiene)nickel, is reported. Using miniemulsions of catalyst solutions in a small amount of hydrocarbon solvent for polymerization, stable di...

Strong `spin'-orbit coupled one-dimensional hole gas is achievable in a Ge nanowire the presence of strong magnetic field. The field lifts two-fold degeneracy subband dispersions, so that effective low-energy dispersion exhibits coupling. Here, we study electrical `spin' manipulation quantum dot for both lowest and second dispersions. Using finite square well to model confining potential, calcu...

Hypothesis Silica nanoparticles can be dispersed in organic solvents (organosols) using surfactants, such as didodecyldimethylammonium bromide (DDAB). DDAB analogues prepared with lathanide tetrahalide counterions, either a high-magnetic moment ion (HoCl3Br, DDAH) or low-magnetic moment one (NdCl3Br, DDAN), are expected to produce charged particles but only DDAH-stabilized dispersions are expec...