carbonates are among the most common soil constituents in arid and semiarid zones. they exhibit many significant differences in their chemical and mineralogical, suite, origin, physical and micromorphological properties and consequently in their activities in soil. the differences cause different properties of calcareous soils. six profiles of aridisols and inceptisols with carbonate accumulati...

An attempt has been made to study the impact of calcium carbonate on soil dielectric properties. The dielectric constant (ε') and dielectric loss (ε'') of soil with increasing percentage of calcium carbonate are measured at 7.0 GHz. These measurements are carried at room temperature. The J-band microwave setup with slotted section and a crystal detector is used for measurements. The two point m...

Calcium carbonate particles with a novel bowknot-like superstructure were fabricated in the presence of poly(sodium 4-styrene sulfate) (PSS) and under the assistance of ultrasonication during the initial reaction stage. X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), selected area electron diffraction (SAED), and field-emis...

The long-term success of coral reefs depends on a positive balance of calcium carbonate production exceeding dissolution, erosion, and material export. As a result of ocean acidification, coral reefs could transition from net accretion to net erosion owing to decreasing rates of calcification and increasing rates of chemical dissolution and bioerosion. Here, I present a fundamental paradigm tha...

BACKGROUND Dairy product and calcium consumption have been associated with modifying body fat and body weight in children and adults. OBJECTIVE In overweight adolescent boys and girls, we aimed to determine the effect of the doubling of habitual calcium intake to the recommended intake from dairy or calcium carbonate on energy balance and purported mechanisms including fecal fat excretion, ma...

Calcium carbonate is an abundant biomineral that is of great importance in industrial or geological contexts. In recent years, many studies of the precipitation of CaCO3 have shown that amorphous precursors and intermediates are widespread in the biomineralization processes and can also be exploited in bio-inspired materials chemistry. In this work, the thorough investigation of a urinary stone...

Calcium salts are often prescribed in the prevention and treatment of osteoporosis. Adverse reactions have been described, mostly concerning to the gastrointestinal tract, parathyroid glands and bone resorption. We report the case of a 52-year-old woman who started treatment with 500 mg per day of calcium-pidolate. 90 minutes after the intake of the second dose, she experienced an itchy maculop...

Two West Indian manatees (Trichechus manatus spp.) were reported with severe emaciation. One animal was a Florida manatee from the Everglades; the other was an Antillean manatee from Cuba. On necropsy, both animals had nephrolithiasis, pyelonephritis, and moderate to severe renomegaly. Histopathology revealed multifocal to diffuse pyelonephritis, interstitial nephritis, and nephrocalcinosis. Th...

[1] We argue that diagnostics of excess dissolved calcium carbonate (TA*) above the saturation horizon cannot be unambiguously interpreted in terms of local in situ dissolution. We examine a three-dimensional numerical model of global ocean circulation and biogeochemistry with explicit representation of the formation and dissolution of calcium carbonate. In particular, dissolution is only allow...

hydraulic attributes play important role in hydrological studies, soil conservation, designing irrigation and drainage systems, soil conservation, and controlling soil erosion in watersheds. their measurements are very tedious and time consuming and due to high spatial variability, a large number of measurements are required for obtaining reliable values. nowadays, prediction of these attribute...