Control over the crystallography, morphology and hierarchical assembly of crystals are important goals in advanced materials engineering with important application potential. Most studies hitherto have concentrated on using different templates for the controlled nucleation and growth of ceramic crystals. In this paper, we demonstrate the crystallization of barium sulfate within thermally evapor...

Microbial processes played a major role in mineral precipitation throughout the Earth’s history. Such processes have been widely discussed for the last few decades with regard to carbonate precipitation. Other than microbial precipitation of carbonates, in natural environments is also of great interest the potential role of microbes in the precipitation of marine barite. Regarding carbonates, o...

Barite plaster has been largely used as shielding material in installations housing gamma radiation sources as well as x-ray generating equipment, in order to minimize exposure to individuals. However, some physical characteristics, such as density, plasticity, resistance to compression and radiation attenuation for the different types of barite plaster commercially available in Brazil are not ...

the komshecheh barite-fluorite deposit is the product of epigenetic hydrothermal mineralizationin dolomitized limestone of middle triassic age. the deposit is structurally and lithologically controlled andoccurs predominantly as bedded stratabound replacement sheets, although the veins and solution-collapsebreccias constitute important modes of occurrence. brecciation, dolomitization, silicific...

Barite is an important additive material to increase the weight of excavation mud. It has been used extensively in the excavation mud industry. The barite particle sizes used in excavation mud is very important. There is a direct relationship between the amount on the sift of 200 and 325 mesh. By reducing particle sizes of the 200 and 325 mesh, the specific gravity of the barite power increased...

Rheology is one of the key drilling fluid properties for controlling sag. Yet, the current understanding of the sag-rheology relationship is limited to a few general guidelines for reducing sag in the field. This paper reviews current understanding of sag and describes the initial stage of work aimed at finding a correlation between fluid rheology and sag performance under laboratory conditions...

abstract  introduction: recently uses of medium and high energy x-rays has been increased in iran and radiotherapy centers along with a variety of accelerators have been installed in some provinces. in the other hand there is no sufficient skill in designing and making radiotherapy treatment rooms. this study was conducted to evaluate the efficacy of different mixtures of barite concrete for sh...

Material fluxes associated with fluid expulsion at cold seeps and their contribution to oceanographic budgets have not been accurately constrained. Here we present evidence that the barium released at cold seeps along the San Clemente Fault zone may significantly impact the geochemical budget of barium within the basin. Barium fluxes at seep localities on the fault scarp, measured with benthic ...