background because of difficulty in obtaining a 24-hour urine collection in children, a random sample of urine is often used to calculate the urinary calcium to creatinine ratio. urinary calcium excretion might be influenced by genetic, geographic area, etc. in this study, the value of urinary calcium, creatinine, sodium and potassium excretion and age–related reference values for urine calcium...

A fundamental study of scale formation of calcium carbonate (CaCO3) for producing oil wells has been carried out. This article presents the study of the prediction of salt deposition in two different synthetic formation waters and investigates the effects of temperature and pressure on calcium carbonate precipitation. The dependence of the induction period of the precipitation of calcium carbon...

backgrounds and aims: stroke incidence rate has increased during the past 2 decades. the question of whether calcium, chloride, potassium, sodium levels are associated with stroke has remained controversial. the present study aimed to evaluate the serum levels of potassium, sodium, calcium, and chloride within stroke patients. materials and methods: the study participants consisted of 53 cconse...

In the present investigation, the oxidizing roasting process of chromite with sodium carbonate to prepare potassium dichromate crystals was studied in the microwave field with air, by heating the chromite and sodium carbonate. The chromite and sodium carbonate heated separately at 1000 ◦C in the microwave oven (frequency: 2.45 GHz; power 1.5 kW) in order to study the microwave absorption proper...

Calcium carbonate is the material that builds up the spicules of the calcareous sponges. Recent results revealed that the calcium carbonate/biocalcite-based spicular skeleton of these animals is formed through an enzymatic mechanism, such as the skeleton of the siliceous sponges, evolutionarily the oldest animals that consist of biosilica. The enzyme that mediates the calcium carbonate depositi...

a simple, mild and practical procedure has been developed for the synthesis of symmetrical and unsymmetrical ethers by using dmso, tbai in the presence of k2co3. we extended the utility of  potassium carbonate as an efficient base for the preparation of ethers. a wide range of alkyl aryl and dialkyl ethers are synthesized from treatment of aliphatic alcohols and phenols with various alkyl halid...

The effect of dietary calcium chloride vs. calcium carbonate on mineral metabolism was studied in cats. Ovariectomized cats and female kittens were fed purified diets with a normal calcium level (9.5 mmol Ca/MJ) but containing either calcium carbonate or calcium chloride, or were fed diets with a high calcium level (17.7 mmol Ca/MJ) containing either calcium carbonate alone or equimolar amounts...

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...