The role of spatial distribution of porous medium patchwise chemical (charge) heterogeneity in colloid transport in packed bed columns is investigated. Colloid transport experiments with carboxyl latex particles flowing through columns packed with chemically heterogeneous sand grains were carried out. Patchwise chemical heterogeneity was introduced to the granular porous medium by modifying the...

[1] The transport of colloid-contaminant complexes and colloid-sized pathogens through soil to groundwater is of concern. Visualization and quantification of pore-scale colloid behavior will enable better description and simulation of retention mechanisms at individual surfaces, in contrast to breakthrough curves which only provide an integrated signal. We tested two procedures for quantifying ...

Colloid centrifugation can be used to separate heterogeneous populations of cells particularly semen samples, which typically contain mixtures of spermatozoa at different stage of maturity together with dead and dying spermatozoa and also non-sperm cells. Colloids can be used to enrich the population of spermatozoa that are viable and functional; these are the spermatozoa that are needed for fe...

Pulmonary artery wedge and plasma colloid osmotic pressures and their relationship to pulmonary edema were investigated in 26 patients with acute myocardial infarction of whom 14 developed pulmonary edema. In the absence of pulmonary edema, both the pulmonary artery wedge pressure and plasma colloid osmotic pressure were in normal range; after onset pulmonary edema, a moderate increase in pulmo...

At the Radiochemical Centre we have recently developed a new 90Y colloid which has greater stability than the currently available 90Y silicate colloid and appears from the results of animal tests to be suitable for the treatment of rheumatoid knee joint effusions. In this report the need for a new 90Y colloid is assessed and the preparation and properties of the new colloid are described. Curre...

We present continuum models to describe colloid release in the subsurface during transient physicochemical conditions. Our modeling approach relates the amount of colloid release to changes in the fraction of the solid surface area that contributes to retention. Equilibrium, kinetic, equilibrium and kinetic, and two-site kinetic models were developed to describe various rates of colloid release...

A new treatment of the phase behaviour of a colloid + nonadsorbing polymer mixture is described. The calculated phase diagrams show marked polymer partitioning between coexisting phases, an effect not considered in the usual effective-potential approaches to this problem. We also predict that under certain conditions an area of three-phase coexistence should appear in the phase diagram. Introdu...

Colloid cysts appear most commonly in the third ventricle, their occurrence in the sellar region is uncommon. The authors report a female patient with a pituitary colloid cyst. She was diagnosed incidentally with a sellar lesion by a routine paranasal computed tomography examination performed for planning of a dental implant surgery. Radiologic examinations revealed a pituitary lesion that was ...

Random telegraph noise in the electric current produced by shot noise is predicted for an array of movable colloid particles by Monte Carlo and molecular dynamics calculations. The electron transport is attributed to the shuttle mechanism where moving colloid particles carry charges. The colloid-particle motion induced by the source-drain voltage shows periodic and/or quasiperiodic vibrations, ...

Colloid cysts are relatively rare intracranial lesions located in the rostral aspect of the third ventricle. They may produce acute hydrocephalus, brain herniation, and lead to death. Although the clinical and imaging features of colloid cysts are well known, their etiology and the factors responsible for their imaging features continue to be a subject of debate. We present the imaging-patholog...