This paper reports the carbonation characteristics of a cement-slag system exposed to accelerated testing, and its improved resistance with increasing MgO content in blast furnace slag, which hydrotalcite-like phase plays key role. Our research showed that started carbonate upon contacting ions bound more than 15 wt% CO2−3 mildly carbonated transition areas. value was positively associated magn...

Carbonate sediments have been deposited in oceans and seas from the Proterozoic up to the present day. Their palaeogeographic distribution, extent and composition changed substantially through time. Recent carbonate platforms are closely linked with reef constructions, but, during the past, non-reefal carbonate production played an important role in the periods of the depressed reef-growth (KIE...

Lead (Pb) contamination in soils of residential properties due to peeling and chipping Pb-based paint can cause human health problems. Phytoextraction is a green technology that has the potential remediate soil Pb. The efficiency phytoextraction dependent on geochemical forms Pb soil. A biodegradable chelating agent, ethylenediaminedisuccinic acid (EDDS), was previously shown enhance removal by...

This paper identified carbonation products in the slag-rich cementitious systems upon three different exposure conditions, namely, long term field, indoor natural exposure, and accelerated testing. Overall, mineralogy of was found to be fundamentally similar under environments. In fully carbonated areas, no monosulfate calcium hydroxide observed, carbonate, hydrotalcite-like phase Ca–Al AFm pha...

The effect of alkalinity on nitrifying biofilm activity was determined by collecting 21-day-old biofilm samples from the top of a full-scale nitrifying trickling filter and evaluating bench-scale nitrate plus nitrite generation rates at (1) various initial carbonate alkalinity concentrations and (2) with four types of available alkalinity: carbonate only, phosphate only, phosphate plus hydroxid...

the aim of this study was to investigate the effect of the addition of commercial lipase in various forms on the acceleration of the ripening of uf-feta cheese. commercial lipase from aspergillus niger was encapsulated by using silica composition based on sol-gel method. lipase was then added to cheeses in three forms, namely, free lipase, encapsulated lipase, and encapsulated lipase with arabi...

Crystals of magnetite (Fe(3)O(4)) and periclase (MgO) in Fe-Mg-Ca carbonate in the Martian meteorite Allan Hills 84001 were studied by using transmission electron microscopy to understand their origin and evaluate claims that the magnetites were made by Martian microorganisms. In magnesian carbonate, periclase occurs as aggregates of crystals (grain size approximately equal to 3 nm) that are pr...

The application of a linear algebraic method to the potentiometric titration of a mixture of tartaric and citric acids and sodium carbonate and sodium hydrogen carbonate (previously treated with strong acid), permits the determination of the concentration of each individual acid and the total equivalent of carbonate in antacids. It is also possible to determine individual concentrations of sodi...

A method is described for the determination of total carbonate by means of acoustic emission. Acoustic signals are generated from effervescence of carbon dioxide when aqueous samples containing carbonate or hydrogencarbonate are acidified. Two approaches are evaluated. The first involves direct mixing of carbonate and acid streams in a flow system. Detection limits around 0.1 M are observed wit...

The feasibility of calcium carbonate cements involving the recrystallisation of metastable calcium carbonate varieties has been demonstrated. Calcium carbonate cement compositions presented in this paper can be prepared straightforwardly by simply mixing water (liquid phase) with two calcium carbonate phases (solid phase) which can be easily obtained by precipitation. An original cement composi...