A three-dimensional particle tracking model for colloid transport in porous media was developed that predicts colloid retention in porous media in the presence of an energy barrier via two mechanisms: (1) wedging of colloids within grain to grain contacts; (2) retention of colloids (without attachment) in flow stagnation zones. The model integrates forces experienced by colloids during transpor...

The reduced hepatic blood flow calculated from hepatic scintigram with 198Au colloid was elucidated as the primary responsible factor for postoperative hepatic insufficiency. However 198Au colloid is no longer in use because of the high levels of radiation. Although 99mTc-phytate behaves similarly to 198Au on imaging, there were discrepancies between the hepatic blood flow index (KL) value and ...

We determine the solvent mediated contribution to the effective potentials for model colloidal or nanoparticles dispersed in a binary solvent that exhibits fluid-fluid phase separation. The interactions between the solvent particles are taken to be purely repulsive point Yukawa pair potentials. Using a simple density functional theory we calculate the density profiles of both solvent species in...

A two-dimensional model for colloid transport in geochemically and physically heterogeneous porous media is presented. The model considers patchwise geochemical heterogeneity, which is suitable to describe the chemical variability of many surficial aquifers with ferric oxyhydroxide-coated porous matrix, as well as spatial variability of hydraulic conductivity, which results in heterogeneous flo...

OBJECT Patients harboring colloid cysts of the third ventricle can present with acute neurological deterioration, or the first indication of the lesion may appear when the patient suddenly dies. The risk of such an occurrence in a patient already identified as harboring a colloid cyst is unknown. The goal of this study was to estimate the risk of acute deterioration in patients with colloid cys...

colloid cysts are mucous-filled masses with an outer fibrous layer. these cysts are rare developmental malformation and not a true neoplasm. they usually found incidentally and are asymptomatic; but in some cases may associate with rapid neurologic deterioration, herniation, and sudden death. recognition of this rare but important diagnosis may result in decreasing mortality. in this report, we...

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...