A composite gastro-retentive matrix for zero-order delivery of highly soluble drug alfuzosin hydrochloride (10mg) has been designed and characterized. Two systems containing polyethylene oxide (PEO), hydroxypropylmethylcellulose (HPMC), sodium bicarbonate, citric acid and polyvinyl pyrrolidone were dry blended and compressed into triple layer and bi-layer composite matrices. Dissolution studies...

The modes of erosion-corrosion are diverse and may vary from being "erosiondominated", where erosion of metal is the dominant process, to "corrosion-dominated", where erosion of oxide scale is the dominant process. The intermediate situation in which erosion of transient oxide is the predominant process is termed "erosion-corrosion-dominated" and describes the regime in which continual formatio...

This study focuses on the numerical modelling of concentrated leak erosion of a cohesive soil by a turbulent flow in axisymmetrical geometry, with application to the Hole Erosion Test (HET). The numerical model is based on adaptive remeshing of the water/soil interface to ensure accurate description of the mechanical phenomena occurring near the soil/water interface. The erosion law governing t...

[1] We have determined the chemical erosion yields for fifteen watersheds in New Zealand, ranging in size from 12.2 to 2928 km. These rates, coupled with previously measured physical erosion yields, allow us to compare these two modes of landscape denudation. The physical erosion yields are some of the highest measured in the world. Although in most instances the chemical erosion yields are onl...

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In contrast to non-cohesive sediments, the incipient motion of cohesive sediments is characterized by much more complex interactions between several sedimentary, biological, and chemical parameters. Thus, site-specific investigations are required to obtain information about the erosion stability of cohesive materials. This becomes even more relevant for contaminated sediments, stored in riverin...

This paper estimates the soil erosion rate and erosion-induced carbon sink using a new approach, and distinguish the contribution from topsoil erosion, gully erosion and landslides. The role of conservation programs on reducing soil erosion is also assessed. Special comments: 1. The abstract is too long and needed to be simplified. Besides, as the soil erosion rate estimated in this paper is mu...

The release of particulate-phase trace metals due to sediment resuspension has been investigated by combining erosion chamber experiments that apply a range of shear stresses typically encountered in coastal environments with a shear stress record simulated by a hydrodynamic model. Two sites with contrasting sediment chemistry were investigated. Sediment particles enriched in silver, copper, an...

Xeropolis is a tell site on the island of Euboea, Greece just to the east of the village of Lefkandi, and was occupied from the Early to Late Bronze Age. Excavations in recent years have provided an opportunity to investigate site formation processes using geoarchaeological and geochemical techniques. Sediments derived from the tell on the southern side have been lost by coastal erosion whilst ...

Stormwater runoff from construction sites has become an increasingly major contributor of fine inorganic sediment input into our streams and rivers. The negative impacts of excess fine sediment loads extend to all segments of the aquatic ecosystems from microbes to fish. While large construction projects represent single major potential pollution sources and are usually more visible, smaller co...