Metal recovery using chitosan

Chitosan is a natural polycationic polymer which possesses valuable properties as a metal recovering and water purifying agent. Applications are —waste water treatment for heavy metal and radio isotope removal and valuable metal recovery, —potable water purification for reduction of unwanted metals, —agriculture—controlled release of trace metals essential to plant growth, —food—complex binding of iron in precooked food to reduce ‘warmed-over flavour’. The interactions of metals with chitosan are complex, probably simultaneously dominated by adsorption, ion-exchange and chelation. To study this it is of utmost importance to work with well characterized chitosans. This has been a problem as available characterizing methodology is limited. Degree of polymerization and deacetylation and the distribution of acetyl groups along the polymer chain is of crucial importance for chitosan metal interacting characteristics. Making chemical derivatives is a way to alter the metal interacting characteristics of chitosan. Chitosan possesses general coagulant/flocculant characteristics towards bio-molecules and surfaces.     

A cavity depth and volume estimation technique to support data collection in an image mining oriented geoprocessing system

Spatially defined information is essential to support decision making in several areas, such as in therapeutic procedures to reduce or healing lesions in human body. So localization together with images and many other data can constitute a database to feed an Image Mining oriented Geoprocessing. Besides that low cost additional infrastructures are attractive to install large-scale use of image capturing and interpretation for health assistance. In such context geometric features of cavities can be remotely captured to monitor patients with wounds called pressure ulcers (PU). An image with linear shadows on the cavity of a model is generated in order to enable the measurement of its deformation caused by depth. This yields maximum depth and volume in an experimental model that are compared with measurements made previously in a conventional manner. Partially satisfactory results suggest improvements in image capturing device and computational procedures.