The flow of dry granular material in a half-filled rotating drum is studied. The thickness of the flowing zone is measured for several rotation speeds, drum sizes and beads sizes (size ratio between drum and beads ranging from 47 to 7400). Varying the rotation speed, a scaling law linking mean velocity vs. thickness of the flow, v approximately h(m), is deduced for each couple (beads, drum). Th...

Since 1991, excavations at Blombos Cave have yielded a well-preserved sample of faunal and cultural material in Middle Stone Age (MSA) levels. The uppermost MSA phase, M1, is dated to c. 75 ka by optically stimulated luminescence (OSL) and thermoluminescence, and the middle M2 phase to a provisional c. 78 ka. Artefacts unusual in a MSA context from these phases include bifacial points, bone too...

chitosan with excellent biodegradable and biocompatible characteristics has received attention as an oral drug delivery vehicle for controlled-release formulations. in this study an enteric-coated capsule containing theophylline-chitosan beads based on 23 factorial designs was prepared as a colon drug delivery system. the theophylline-chitosan gel beads were formulated by adding the drug-contai...

using ion-exchange resins, a multiple-unit type of oral floating dosage system has been prepared to prolong gastric emptying time of dosage form. the system is composed of beads of drug-resin complex, which are loaded with bicarbonate ions and coated with a hydrophobic polymer. the system is so designed that when the beads reach the stomach, chloride ions are exchanged with bicarbonate and drug...

Particles and solutes are excluded from the vicinity of hydrophilic surfaces, leaving large microsphere-free regions known as exclusion zones (EZs). Prior work had indicated that EZs could extend to distances of up to several hundred micrometers from the nucleating surface. These observations were made on large, extended surfaces, leaving open the question whether EZ size might depend on the ch...

We developed a method for production of arrays of platinum nanocrystals of controlled size and shape using templates from ordered silica bead monolayers. Silica beads with nominal sizes of 150 and 450 nm were self-assembled into monolayers over strontium titanate single crystal substrates. The monolayers were used as shadow masks for platinum metal deposition on the substrate using the three-st...

Using a biochemically complex cytoplasmic extract to reconstitute actin-based motility of Listeria monocytogenes and polystyrene beads coated with the bacterial protein ActA, we have systematically varied a series of biophysical parameters and examined their effects on initiation of motility, particle speed, speed variability, and path trajectory. Bead size had a profound effect on all aspects ...

Translucent photocatalytic reactor structures are interesting for the design of small and large scale reactors. Altering base element size structure impacts packing parameters. Decreasing increases available surface area which potential catalyst load per volume. However, a smaller number light scattering boundaries, resulting in higher energy loss. This work elaborates on influence absorption e...

Chitosan with excellent biodegradable and biocompatible characteristics has received attention as an oral drug delivery vehicle for controlled-release formulations. In this study an enteric-coated capsule containing theophylline-chitosan beads based on 23 factorial designs was prepared as a colon drug delivery system. The theophylline-chitosan gel beads were formulated by adding the drug-contai...

The present work aimed to increase the thermostability and pH stability of lipase produced from Penicillium chrysogenum SNP5 using different anionic carriers. The immobilized lipase from the fungus on 1.25% sodium alginate beads and 12% polyacrylamide beads retained 37.28 and 59.75% immobilization efficiency, respectively, on 3 mm bead size. Immobilized lipase on calcium alginate and polyacryla...