We carried out a theoretical study to investigate the thermodynamics and the kinetics of the activation of the anticancer drug carboplatin in a carbonate buffer, a process which has been suggested to play an important role in the uptake, antitumor activity and toxicity of this drug. The initial stages of this process have been investigated by considering both the carbonate and the bicarbonate i...

Molten carbonates are highly inviscid liquids characterized by low melting points and high solubility of rare earth elements and volatile molecules. An understanding of the structure and related properties of these intriguing liquids has been limited to date. We report the results of a study of molten sodium carbonate (Na2CO3) which combines high energy X-ray diffraction, containerless techniqu...

Introduction: Air-powder polishing devices are increasingly used for stain and plaque removal. However, besides cleaning the tooth surface, they may increase the surface roughness of the dental tissues. This in turn may result in plaque accumulation and superficial degradation. Thus the aim of this study was to assess the influence of three different abrasive agents: Pumice, Sodium bicarbonate ...

The role of coccolithophores in the biogenic carbonate cycle was studied in the coastal upwelling zone off Concepción, Chile (36°S), and in adjacent oceanic waters during spring 2004. Coccolithophore abundance and diversity increased steadily from coastal to oceanic regions. The presence of an active coastal upwelling center clearly partitioned the study area into coastal, transition and two oc...

A surface-controlled dissolution of cylindrical solid particles model is applied to potassium carbonate, sodium bicarbonate and sodium carbonate in dimethylformamide at elevated temperatures. Previously published data for the dissolution of potassium carbonate is interpreted assuming a cylindrical rather than a spherical shape of the particles, the former representing a closer approximation to ...

Larger symbiont-bearing foraminifera are prominent and important producers of calcium carbonate in modern tropical environments. With an estimated production of at least 130 million tons of CaCO(3) per year, they contribute almost 5% of the annual present-day carbonate production in the world's reef and shelf areas (0-200 m) and approximately 2.5% of the CaCO(3) of all oceans. Together with non...

microfacies and depositional environments interpretation of asmari and jahrum were studied in boreholes 2, 10 and 11 in gol- khari oil field. based on petrographic criteria, fauna assemblages, biofacies and sedimentary textures, 21 carbonate microfacies and 3 non- carbonate petrofacies were recognized. these microfacies were deposited in distinct depositional environments including tidal flat, ...

The influence of organic additives, β-cyclodextrin, HEDTA, L-aspartic acid and L-glutamic acid on crystal growth of calcium carbonate via vapour diffusion method has been investigated. In the absence of additive, regular rhombohedral calcium carbonate crystal habit resulted. Whereas in presence of additive, calcite with truncated, aggregated rhombohedral sub crystals and elongated hexagonal mor...

In the present work the internal sulfate attack on pastes made from pure clinker phases was studied. Two binders were produced: (a) a binder with 2% C3A and 18% C4AF content; (b) a binder with 10% C3A and C4AF content each. Gypsum was used as the sulfate bearing compound, while calcium carbonate added to differentiate the binders produced. The phases formed were identified by XRD analysis. The ...

The abundance of reef builders, non-builders and the calcium carbonate produced by communities established in Calcification Accretion Units (CAUs) were determined in three Abrolhos Bank shallow reefs during the period from 2012 to 2014. In addition, the seawater temperature, the irradiance, and the amount and composition of the sediments were determined. The inner and outer reef arcs were compa...