The transition from invertebrate calcium carbonate-based calcite and aragonite exo- and endoskeletons to the calcium phosphate-based vertebrate backbones and jaws composed of microscopic hydroxyapatite crystals is one of the great revolutions in the evolution of terrestrial organisms. To identify potential factors that might have played a role in such a transition, three key domains of the vert...

Calcium is an essential nutrient required in substantial amounts, but many diets are deficient in calcium making supplementation necessary or desirable. The objective of this study was to compare the oral bioavailability of calcium from calcium formate, a new experimental dietary calcium supplement, to that of calcium citrate and calcium carbonate. In a four-way crossover study, either a placeb...

OBJECTIVES The tolerability and efficacy of lanthanum carbonate has not been studied in the Indian population. This study was, therefore, undertaken to compare the efficacy and tolerability of lanthanum carbonate with calcium acetate in patients with stage 4 chronic kidney disease. DESIGN A randomized open label two group cross-over study. MATERIALS AND METHODS Following Institutional Ethic...

Calcium carbonate is an important component in exoskeletons of many organisms. The synthesis of calcium carbonate was performed by mixing dimethyl carbonate and an aqueous solution of calcium chloride dihydrate. The precipitation product was characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrar...

BACKGROUND Hyperphosphatemia is common in end-stage renal disease patients. Objective of this study is to compare the hypercalcaemic effect and phosphate binding power of calcium acetate and calcium carbonate in end-stage renal disease patients on maintenance haemodialysis. METHODS This randomised control trial was conducted in four phases with calcium acetate or calcium carbonate. Sixty-four...

Calcium carbonate is an abundant substance that can be created in several mineral forms by the reaction of dissolved carbon dioxide in water with calcium ions. Through biomineralization, organisms can harness and control this process to form various functional materials that can act as anything from shells through to lenses. The early stages of calcium carbonate formation have recently attracte...

abstract water is the most common carier used to dilute herbicides and their application. researches had shown that water quality is an important factor in some herbicide efficacy. in order to study the effect of water hardness on 2,4-d efficacy, an experiment was carried out under controlled conditions in 2010 at the college of agriculture, ferdowsi university of mashhad. experimental treatmen...

the waste tyres represent a source of energy and valuable hydrocarbon products. waste tyres were pyrolysed catalytically in a batch reactor under atmospheric pressure. the effects of basic catalysts (mgo and caco3) were studied on the pyrolysis products. the distribution ratio of gas, liquid and char with mgo and caco3 were 24.4:39.8:35.8 wt % and 32.5:32.2:35.2 wt % respectively at 350°c for 2...

We designed a novel multifunctional β-sheet peptide template for calcium carbonate mineralization. The template self-supplies the mineral source, a carbonate ion, by hydrolysis of urea, and regulates the crystal phase and morphology of the obtained calcium carbonate.

This study was designed to determine the effects of an aluminum hydroxide antacid and a calcium carbonate antacid on the bioavailability of ciprofloxacin (Cipro). Cipro (750 mg) was administered orally to 12 healthy volunteers in a three-way randomized crossover design. The three treatments included Cipro alone, four 850-mg calcium carbonate tablets taken 5 min before Cipro, and three 600-mg al...