The electron subband structure in a thin (100) silicon film is analyzed based on a two-band k·p theory. For unprimed subbands the dependence of the nonparabolicity parameter on film thickness is obtained. The two-band k·p theory gives a thickness dependence of the effective masses for primed subbands. Limitations of the model are discussed. The importance of the nonparabolicity parameter depend...

The aim of the present study was to improve solubility and dissolution of the poorly aqueous soluble drug, etoricoxib by solvent evaporation technique using various sugar carriers, such as lactose, sucrose, and mannitol. Etoricoxib solid dispersions and their respective physical mixtures using lactose, sucrose, and mannitol were prepared in different ratios by solvent evaporation technique. The...

The objective of the present investigation was to study the effect of polyethylene glycol 4000 (PEG 4000) on in vitro dissolution of gliclazide from solid dispersions. Initial studies were carried out using physical mixtures of the drug and carrier. Solid dispersions were prepared by the melting or fusion method.Phase and saturation solubility study, in vitro dissolution of pure drug, physical ...

Rheological studies of the ceramic based concentrated titania nanoparticle dispersions showed a clear correlation between molecular structure of the cationic polymers used as dispersants and the viscosity of the slurries. Dynamic viscosity of the electrostatically stabilized alkaline (pH 10.0) dispersions of the bare titania nanopowders with a solid loading of 15 – 25 wt.% was rather high (abou...

The purpose of this study is to develop and characterize the nature of a solid dispersion system of nifedipine in a polymer matrix consisting of PVP K30 and poloxamer 407. Dispersions consist of drug, polymeric carrier and surfactant carrier. Binary solid dispersions consisting of nifedipine and PVP K30 were developed by solvent evaporation method. Poloxamer 407, surfactant carrier was incorpor...

We developed solid dispersions, using the gas anti-solvent technique (GAS), to improve the oral bioavailability of the poorly water-soluble active component oridonin. The solubility of oridonin in supercritical carbon dioxide was measured under various pressures and temperatures. To prepare oridonin solid dispersions using the GAS technique, ethanol was used as the solvent, CO(2) was used as th...

The filtration behaviour of some clay–water dispersions was studied. Two Spanish fibrous phyllosilicates (sepiolite from Vicálvaro and palygorskite from Turón) and a commercial bentonite (Bentopharm©, UK) with similar sizes and different morphologies (fibrous and/or laminar) were selected as model clays. Sepiolite from Vicálvaro is an almost pure fibrous sample, Bentopharm© presents a high amou...

in this work attempts were made to evaluate k+-sds and hydrocolloid polymer-sds interactions in flocculation of megestrol acetate dispersions to enhancetheir stability as a part of suspension formulation. different dispersions of micronized megestrol acetate and sds were prepared. kcl and kh2po4 and their corresponding sodium salts were added to the dispersions and the preparations were evaluat...