Abstract Raman spectra (532 nm diode laser) of gypsum, syngenite and görgeyite powders were studied from 273 to 83 K every −10 K. Although it was found that not all the peaks are temperature-sensitive, effect temperature on signal some bands modelled. It observed main three sulfates shift toward higher wavenumbers as decreases. The strengthening bonds causes an increase in energy and, consequen...

The choice of a pure cohesive or a pure frictional viscoplastic model to represent the rheological behaviour of a flowslide is of paramount importance in order to obtain accurate results for real cases. The principal goal of the present work is to clarify the influence of the type of viscous model-pure cohesive versus pure frictional-with the numerical reproduction of two different real flowsli...

a semi-batch crystallization system is used to determine growth kinetics and morphology of barium carbonate crystals, under a constant ph value and constant temperature in the various relative supersaturations. results show that crystal growth rate satisfies a first-order kinetic expression at high relative supersaturation, while at relative supersaturation values lower than 3,  the kinetic exp...

This paper describes some physical, structural, and biological properties of gypsum bioceramics doped with various amounts of strontium ions (0.19-2.23 wt%) and compares these properties with those of a pure gypsum as control. Strontium-doped gypsum (gypsum:Sr) was obtained by mixing calcium sulfate hemihydrate powder and solutions of strontium nitrate followed by washing the specimens with dis...

Abstract: Load-bearing cold-formed steel (CFS) walls sheathed with double layers of gypsum plasterboard on both sides have demonstrated good fire resistance and attracted increasing interest for use in mid-rise CFS structures. As the main connection method, screw connections between CFS and gypsum sheathing play an important role in both the structural design and fire resistance of this wall sy...

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...

This study aims to obtain insights into the retardation mechanism of citric acid in an ettringite-based binder from ladle slag and gypsum. The hydration kinetics phase assemblage were experimentally investigated thermodynamically modelled. Additionally, effects on synthetic ettringite studied further understanding interaction between this organic ligand crystal. Experimental results reveal that...

Acid soil covers one third of the world arable lands. Excess Al and H in acid soil are not favorable for most plants. Calcium carbonates and gypsum (CaSO4) are used to improve chemical status of the acid soil. However, application of Ca cation may sometimes enhance dispersion and deteriorate soil physical properties. Presenting study discusses effect of non-ionic polyacrylamide (PAM) applicatio...