We model the intercolloidal interaction by a hard-sphere Yukawa repulsion to which is added the long-range van der Waals attraction. In comparison with the Derjaguin-Landau-Verwey-Overbeek repulsion, the Yukawa repulsion explicitly incorporates the spatial correlations between colloids and small ions. As a result, the repulsive part can be expressed analytically and has a coupling strength depe...

Dynamic mechanical analysis (DMA) was used to characterize biomedical composites consisting of synthetic hydroxyapatite (HA) particulate reinforced polyethylene (PE). The effects of the HA volume fraction, temperature and HA particle on the storage modulus (E(I)) and damping (tan delta) were investigated. Increasing HA volume fractions increased E(I) and decreased tan delta. E(I) was found to b...

introduction : in the recent years, due to the wide spread of resistant bacteria on one side and several different reports about the side effects of chemical drugs on the other side, vast researches on the medicinal plants have been started. in this study, antimicrobial effect of total extract of tribulus terrestris l . and its fraction containing benzoxazine derivative (terresoxazine) was stud...

Gaining fundamental knowledge about diffusion in crowded environments is of great relevance in a variety of research fields, including reaction engineering, biology, pharmacy and colloid science. In this work, we determine the effective viscosity experienced by a spherical tracer particle immersed in a concentrated colloidal dispersion by means of Brownian dynamics simulations. We characterize ...

How does the size of the glial and neuronal cells that compose brain tissue vary across brain structures and species? Our previous studies indicate that average neuronal size is highly variable, while average glial cell size is more constant. Measuring whole cell sizes in vivo, however, is a daunting task. Here we use chi-square minimization of the relationship between measured neuronal and gli...

Bioavailability research of soil metals has advanced considerably from default values to validated in vitro bioaccessibility (IVBA) assays for site-specific risk assessment. Previously, USEPA determined that the soil-size fraction representative of dermal adherence and consequent soil ingestion was <250 μm. This size fraction was widely used in testing efforts for both in vivo and in vitro expe...

kinetics of the chemical leaching of chalcocite from a low-grade copper ore in a ferric sulfate medium was investigated using the constrained least square optimization technique. the experiments were carried out for different particle sizes in both the reactor and column at constant eh, ph, and temperature. the leaching rate increased with increase in the temperature. about 50% of the cu recove...

Background: For preclinical evaluations of radiopharmaceuticals, most studies are carried out on mice. Values of electron specific absorbed fractions (SAF) have had vital role in the assessment of absorbed dose. In past studies, electron specific absorbed fractions were given for limited source target pairs using older reports of human organ compositions.Objective: Electron specific absorbed fr...

the effect of pre-existing nano sized precipitates on the mechanisms and rate of grain refinement has been investigated during the severe plastic deformation. a binary al–0.2sc alloy, containing coherent al3sc particles, of 3.62 nm in diameter has been deformed by accumulative roll bonding up to 10 cycles. the resulting deformed structures were quantitatively analyzed using electron backscatter...