In the present study, the potential for the alkali–silica reaction (ASR) in radiation shielding concrete containing special aggregates is presented. The tests were performed on two kinds of aggregate: (1) high-density aggregate to absorb the gamma radiation (barite, magnetite, and hematite) and (2) mineral with high bound water content to attenuate the neutron flux (serpentinite). The optical m...

In Palaeozoic rocks of South-eastern Bosnia (SEB) there are numerous, but very small vein and replacement barite ore deposits containing up to 10% Pb-Zn-Fe-Cu sulphides. Their geochemical characteristics are compared with large barite monosulphide (Hg-tetrahedrite) ore deposits in Mid-Bosnian Schist Mountains (MBSM). The 87Sr/86Sr isotope ratios in the barites of both areas are very similar, (0...

In deep-sea geothermal rift zones, the dispersal of hydrothermal fluids of moderately-high temperatures typically forms subseafloor mounds. Major mineral components of the crust covering the mound are barite and metal sulfides. As a result of the continental rifting along the Red Sea, metalliferous sediments accumulate on the seafloor of the Atlantis II Deep. In the present study, a barite crus...

Fluorite, barite and calcite are important industry minerals. However, they often co-exist, presenting difficulty in selectively separating them due to their similar surface properties. In this study, valonea extract and sodium fluosilicate were used as depressants to selectively separate them by flotation, with sodium oleate as the collector. The single mineral flotation results showed that va...

doi: 10.1130/G33006.1 2012;40;675-678 Geology M.T. Gonzalez-Muñoz, F. Martinez-Ruiz, F. Morcillo, J.D. Martin-Ramos and A. Paytan barite formation Precipitation of barite by marine bacteria: A possible mechanism for marine Email alerting services articles cite this article to receive free e-mail alerts when new www.gsapubs.org/cgi/alerts click Subscribe to subscribe to Geology www.gsapubs.org/s...

Bacterial precipitation of barite (BaSO(4)) under laboratory conditions is reported for the first time. The bacterium Myxococcus xanthus was cultivated in a solid medium with a diluted solution of barium chloride. Crystallization occurred as a result of the presence of live bacteria and the bacterial metabolic activity. A phosphorous-rich amorphous phase preceded the more crystalline barite for...

Ra, Ra and Ba distributions as well as Ra/Ra and Ra/Ba ratios were measured in seawater, suspended and sinking particles at the DYFAMED station in the Western Mediterranean Sea at different seasons of year 2003 in order to track the build-up and fate of barite through time. The study of the Raex/ Raex ratios (Raex = Ra activities corrected for the lithogenic Ra) of suspended particles suggests ...

The construction of concrete structures for radiological protection in sanitary facilities requires a series constructive conditions that guarantee safety. influence the correct bunkers design, wall thicknesses and type materials used is essential to ensure effective protection. use barite aggregate common resource improve radiation attenuation capacity walls. present study analyses structure b...