Cement-based cementitious materials present an alkaline environment and mainly exist in the form of Ca(OH)2. Phosphogypsum, as a retarder materials, is often added to cement instead gypsum, fluorine by-product phosphogypsum also fixed CaF2. These cement-based serve environments containing carbonate groundwater, which changes stability solidified This paper studied solid liquid Ca(OH)2-CaF2, Ca(...

The effect of cosolvents on the solubility equilibria near the critical end-point of binary mixtures is analyzed. The problem has received recent attention for the particular case of ionic cosolvents (Mazo, R. M. J. Phys. Chem. B 2007, 111, 7288-7290), where a pronounced salting-out effect was predicted. Here we make a thermodynamic analysis to view the problem from a different perspective. Our...

Lead (Pb) solubility is commonly limited by dissolution–precipitation reactions of secondary mineral phases in contaminated soils and water. In the research described here, Pb free Pb2+ ion activities were measured following precipitation minerals from aqueous solutions containing sulfate or carbonate a 1:5 mole ratio absence presence phosphate over pH range 4.0–9.0. Using X-ray diffraction Fou...

To allow for accurate calculations of calcium carbonate scaling in highly saline produced waters, we present a comprehensive thermodynamic model based on the electrolyte nonrandom two-liquid (eNRTL) activity coefficient equation aqueous Na+-Ca2+-Cl–-HCO3–-CO32–-CO2 system. The eNRTL binary interaction parameters H2O:(Na+-CO32–) pair, H2O:(Na+-HCO3–) (Na+-Cl–):(Na+-CO32–) and (Na+-Cl–):(Na+-HCO3...

a thermodynamic study on the interaction between zinc ion (zn2+) and human growth hormone(hgh) was studied at two temperatures of 27c and 37c in aqueous solution using an isothermal titrationcalorimetry. it was found that there is a set of three identical and non-interacting binding sites for zn2+ ions. the intrinsic dissociation equilibrium constant and the molar enthalpy of binding are 1.54...

We assessed the relative merits of two approaches for including polarization effects in classical force fields for the sulfate anion. One of the approaches is the explicit shell model for atomic polarization and the other is an implicit dielectric continuum representation of the electronic polarization, wherein the polarizability density is spatially uniform. Both the solvation and ion associat...

Highly concentrated NaCl brines are important geothermal fluids; chloride complexation of metals in such brines increases the solubility of minerals and plays a fundamental role in the genesis of hydrothermal ore deposits. There is experimental evidence that the molecular nature of the NaCl–water system changes over the pressure–temperature range of the Earth’s crust. A transition of concentrat...