New occurrences of free gold were identified during fieldwork at outcrops located in the western part of the Castro Basin, state of Paraná. These are associated with silicified and sulfide-rich zones in hydrothermally-altered volcanic rocks. The aerogeophysical data indicate that the areas of the new targets show high K and eU relative to eTh, suggesting intense hydrothermal alteration. The str...

Municipal solid waste used for landfill becomes stabilized, or aged, some years after placement, and can be safely excavated; the term 'mineralized refuse' is used in this study. The adsorptions of phosphorus, and the nitrification of the mineralized refuse and clay, were investigated by batch incubation. The variation of phosphorus adsorption in the mineralized refuse was fitted to the Freundl...

introduction the ramand area, southwest of buin- zahra, about 60 kilometers from qazvin, lies in the igneous belt of the urmieh-dokhtar region, the main structural zone of north-central iran. rhyodacite and rhyolite lava flows are the principal host rocks of mineralization and alteration of the area, most of which occurs in faulted and brecciated zones alongmaj or northwest-trending fault syste...

Dentin is a mesenchymal tissue, and, as such, is based on a collagenous matrix that is reinforced by apatite mineral. Collagen fibrils show piezoelectricity, a phenomenon that is used by piezoresponse force microscopy (PFM) to obtain high-resolution images. We applied PFM to image human dentin with 10-nm resolution, and to test the hypothesis that zones of piezoactivity, indicating the presence...

An iron-poor stream of nearly neutral pH polluted by mine tailings has been investigated for a natural phenomenon responsible for the polishing of heavy metals in mine wastewaters. A white mineralized mat, which was determined to be hydrozincite [Zn(5)(CO(3))(2)(OH)(6)] by X-ray diffraction analysis, was observed in the stream sediments mainly in spring. The precipitate shows a total organic ma...

The results on the effectiveness of five 2D electrical resistivity tomography (ERT) survey profiles for Ag-Pb-Zn, fluorite, and barite exploration Mississippi Valley Type (MVT) magmatic deposits northeast Mexico, are presented. were made in areas with mining activities or mineralization outcrops. Schlumberger, dipole-dipole, Wenner array configurations used measurements. showed that electric ca...

A bacterium that was capable of metabolizing atrazine at very high concentrations (>1,000 ppm) was isolated from a herbicide spill site. The organism was differentiated by observing clearing zones on indicator agar plates containing 1,000 ppm atrazine. Detailed taxonomic studies identified the organism as a Pseudomonas sp., designated ADP, that was dissimilar to currently known species. Pseudom...