this study deals with the uptake of cd2+ and  mn2+ ions from contaminated water using two iranian natural clinoptilolite-rich tuffs from meyaneh (z-m), and semnan (z-s) regions , and a synthetic zeolite-p from z-m sample (z-p) under static (batch operation) and dynamic (column operation) conditions. to investigate the selectivity of the zeolites toward cd2+ and mn2+ cations, the ion exchange is...

U–Th–Pb isotopic systems have been studied in submillimeter-thick outermost layers of Quaternary opal occurring in calcite–silica fracture and cavity coatings within Tertiary tuffs at Yucca Mountain, Nevada, USA. These coatings preserve a record of paleohydrologic conditions at this site, which is being evaluated as a potential high-level nuclear waste repository. The opal precipitated from gro...

This work presents the results of study physical, chemical, mineralogical and pozzolanic properties altered volcanic tuffs (AVT) that lie in Los Frailes caldera, south Iberian Peninsula, demonstrates their qualities as pozzolans for manufacturing mortars cements high mechanical strength. The main objective this research is to show what extent AVTs can replace portland cement (PC) mortars, with ...