The area of interest is located on the eastern flank of the Andean Cordillera, San Juan province, Argentina. The 3600 km2 area is characterized by Siluro-Devonian to Neogene sedimentary and igneous rocks and unconsolidated Quaternary sediments. Epithermal, porphyry-related, and magmatic-hydrothermal breccia-hosted ore deposits, common in this part of the Frontal Cordillera, are associated with ...

NaY zeolites with different framework Si/Al ratios were synthesized via hydrothermal technique. Structural characteristics of the synthesized zeolites were determined by using XRD, XRF, SEM, BET analyses. The effects of operating conditions of hydrothermal dealumination, i.e. time, temperature and partial pressure of water vapor on dealumination of the Y zeolites framework and their structure w...

microporous hydroxy-sodalite zeolite membranes with different morphologies were synthesized via secondary growth technique with vacuum seeding on tubular α-al2o3 supports at two different synthesis conditions (i.e. two different routes). microstructures of the synthesized membranes were characterized by x-ray diffraction (xrd), scanning electron microscope (sem) and single gas permeation using ...

the importance of dietary fiber in normal and therapeutic diets has been acknowledged by numerous authors in recent years. dietary fiber has different physiological effects on human health. the recommended daily intake of dietary fiber is about 30 g, but less than this is often consumed. wheat bran is an excellent source of dietary fiber and is used to fortify foods. the nutritional benefits of...

Deep-sea hydrothermal vent fields are areas on the seafloor with high biological productivity fueled by microbial chemosynthesis. Members of the Aquificales genus Persephonella are obligately chemosynthetic bacteria, and appear to be key players in carbon, sulfur, and nitrogen cycles in high temperature habitats at deep-sea vents. Although this group of bacteria has cosmopolitan distribution in...

As seed dormancy is released within a seed population, both the rate and percentage of germination increase progressively with increasing dose of a dormancy-breaking treatment or condition. Population-based models can account for this behaviour on the basis of shifting response thresholds as dormancy is alleviated. In particular, hydrothermal time analysis of germination sensitivity to water po...

Cu/Cu2O nano-heterostructure hollow spheres with a submicron diameter (200-500 nm) were prepared by a microwave-assisted hydrothermal method using Cu(OAc)2·H2O, PVP and ascorbic acid solution as the precursors. The morphology of the products could evolve with the hydrothermal time from solid spheres to thick-shell hollow spheres, then to thin-shell hollow spheres, and finally to nanoparticles. ...

The analysis of the dissolved organic fraction of hydrothermal fluids has been considered a real challenge due to sampling difficulties, complexity of the matrix, numerous interferences and the assumed ppb concentration levels. The present study shows, in a qualitative approach, that Stir Bar Sorptive Extraction (SBSE) followed by Thermal Desorption - Gas Chromatography - Mass Spectrometry (TD-...

Article history: Received 11 July 2012 Accepted 15 January 2013 Available online 7 February 2013 Editorial handling by Peter Birkle Groundwater chemistry and isotope data from 44 public supply wells in the Napa and Sonoma Valleys, California were determined to investigate mixing of relatively shallow groundwater with deeper hydrothermalfluids.Multivariate analyses includingCluster Analyses,Mult...