Two groups of concrete mixtures, one without sodium sulfate and other with sodium sulfate, as an activator, were made with recycled powdered gypsum-wallboard for this investigation. Group 1 concrete mixtures were made using up to 20% of ASTM Class C fly ash and 20% powdered gypsum while Group 2 contained up to 60% of fly ash and 20% of powdered gypsum by mass. Relevant properties of concrete we...

This research is a part of a wide range investigation on the use of flue gas desulphurisation (FGD) in construction applications. It reports some results on the porosity and pore size distribution of cement paste containing varying amounts of fly ash-gypsum blends as partial replacement of cement. The cement was replaced with 25% of different blends of fly ash and gypsum. The gypsum content ran...

BACKGROUND This study evaluated the survival of the most prevalent oral bacteria and fungi (Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, and Candida albicans) in dental casts, and compared changes in the amounts of these microorganisms at different time intervals to determine how long dental casts may pose threat to the health of dental personnel and patients. MATERIAL AND ...

The current research included the preparation of dental stones from local raw gypsum and boiling it with a solution 30% sodium chloride using reflex method. According to study, there is no country in Middle East that produces stones. As details method manufacturing are not published considered very confidential by international companies, when taking into account price stone twice plaster, beco...

Fluidized gas desulfurization gypsum is a popular agricultural soil amendment used to increase calcium and sulfur contents, and reduce aluminum toxicity. Due to its surface application in conservation tillage systems and high solubility, the soluble components of gypsum may be transferred with agricultural runoff into receiving waters. The current study measured toxicity of gypsum to Ceriodaphn...

The sorption of dissolved inorganic pollutants into the structure of minerals is an important process that controls the mobility and fate of these pollutants in the Earth’s crust. It also modifies the surface structure and composition of the host mineral, affecting its crystallization kinetics. Here, we investigate the effect of hexavalent chromium, Cr(VI), on the nucleation and growth of gypsu...