due to the abundance of the non-coking coal and limitations as well as the high costs of the natural gas, the presentstudy examined the direct reduction of hematite (iron oxide) ore in the temperature range of 800-1000 °c by thenon-coking coal volatiles. approximately, 74.9% of the total amounts of volatiles and gases exit the coal up to800°c. the onset temperature to exit volatiles from the no...

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...

Carbonated hydroxyapatite is the mineral found in vertebrate bones and teeth, whereas invertebrates utilize calcium carbonate in their mineralized organs. In particular, stable amorphous calcium carbonate is found in many crustaceans. Here we report on an unusual, crystalline enamel-like apatite layer found in the mandibles of the arthropod Cherax quadricarinatus (freshwater crayfish). Despite ...

BACKGROUND High levels of serum phosphorus both at baseline and during follow-up are associated with increased mortality in dialysis patients, and administration of phosphate binders was independently associated with improved survival among hemodialysis population. Calcium-based phosphate binders are the most commonly used phosphate binders in developing countries for their relatively low costs...

A consolidating product based on nanoparticles of slaked lime (Ca(OH)2) dispersed in isopropyl alcohol was exposed under different relative humidities (RH), 33%, 54%, 75% and 90% during 7, 14, 21 and 28 days. The characterization of the calcium hydroxide nanoparticles and the formed calcium carbonate polymorphs has been performed by Micro-Raman spectroscopy, Transmission Electron Microscopy (TE...

The heterogeneous uptake and reactivity of formic acid (HCOOH), a common gas-phase organic acid found in the environment, on calcium carbonate (CaCO(3)) particles have been investigated using a Knudsen cell reactor, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). FTIR measurements show that the adsorption of formic acid on the surface of calcium carbonate ...

BACKGROUND Calcium is an essential mineral often taken as a daily, long-term nutritional supplement. Data suggests that once-daily dosing is important with regard to long-term compliance of both drugs and nutritional supplements. OBJECTIVE This study was undertaken to compare the bioavailability of a single serving of two calcium supplements in healthy, premenopausal women. DESIGN A two-per...

Calcium carbonate (CaCO3) is widely used in pharmaceutical industries and as a supplement in probiotics. The present study was designed to evaluate the effect of biofield energy treatment on the physicochemical properties of the CaCO3. The CaCO3 powder was divided into two parts and referred as control and treated. The control part was remained untreated, whereas treated part was subjected to T...

This work explores the effect of additives on the pouring temperature in a waterworks and industrial calcium fluoride sludge co-melting system. Two kinds of sludge were mixed in various ratios to find a mixing ratio at which the operating temperature for subsequent additive tests was relatively low. Various proportions of either sodium carbonate (Na2CO3) or potassium carbonate (K2CO3) reagent w...

A calcium carbonate suspension, encapsulated within particles of calcium alginate hydrogel, is proposed as a drug delivery device susceptible to ultrasound disruption. Spheres approximately 1mm in diameter were prepared by the coaxial airflow method from mixtures of 1% sodium alginate (m/v) and each of 50%, 75% and 100% calcium carbonate (m/v) in distilled water. This product was subjected to c...