this study was conducted to characterize the reactivity of carbonates in the surface horizons of 20 soils (entisols and aridisols) from central region of iran. the samples were analyzed for calcium carbonate equivalent (cce), active calcium carbonate equivalent (acce), non-active calcium carbonate equivalent (n.acce), carbonate mineralogy and surface area of carbonates (ssa) through n2 adsorpti...

abstract the availability of heavy metals in the soil is related to their partitioning between solution and solid phases and expressed by sorption isotherm. twenty surface soil samples (0-30 cm) belonging to five soil subgroups were taken from agricultural regions of western azerbaijan province. the sorption isotherms of pb were determined by equlibrating the soil with solutions containing 0, 1...

Soil cation exchange capacity (CEC) depends on the extent and negative charge density of surfaces of soil mineral and organic components. Soil water sorption also depends on the extent of such surfaces, giving thus way to significant relationships between CEC and hygroscopic moisture (HM) in many soils. In this work, we explored whether CEC could be accurately predicted from HM in agricultural ...

information about forms of phosphorus (p) is important for the evaluation of p status in soil and also understanding of the soil fertility and plant nutrition. to obtain such information and to determine the relationship between the p forms from soil characteristics, amount of different organic and inorganic p forms of 20 soil composite samples of eastern azerbaijan province, iran were determin...

Oral calcium carbonate (0-5 g, pH 9-4) increased serum gastrin and gastric acid output with slight but insignificant change in serum calcium. A similar rise in serum calcium during an intravenous infusion of calcium gluconate failed to increase serum gastrin and gastric acid output. Both intragastric calcium actions were abolished by acidification of the calcium carbonate solution (pH 1-0). The...

Our previous research has demonstrated that dissolved organic matter (DOM) influences calcium carbonate mineral formation in surface and ground water. To better understand DOM mediation of carbonate precipitation and DOM co-precipitation and/or incorporation with carbonate minerals, we characterized the content and speciation of DOM in carbonate minerals and in the lake water of Pyramid Lake, N...

BACKGROUND We recently determined that in hemodialysis patients, the use of calcium salts to correct hyperphosphatemia led to progressive coronary artery and aortic calcification as determined by sequential electron beam tomography (EBT) while the use of the non-calcium-containing binder sevelamer did not. Whether the specific calcium preparation (acetate vs. carbonate) might influence the like...

A mechanism of the transport of nanocrystalline doped calcium carbonatephosphates through the membrane on the model of interaction with phospholipids is considered. Nanocrystalline doped calcium carbonate – phosphates are perspective to transport of the cations in a living cell. Kinetics of the synthesis of nanocrystalline doped calcium carbonatephosphates are non-linear kinetics. Biomaterial b...