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Pressure, density and temperature (p, ρ, T) data and apparent molar volumes, Vфo, of aqueous calcium acetate solutions Ca(CH3COO)2(aq) over a wide range of temperatures from 273.15 to 353.15 K, pressures up to p = 100 MPa and molalities m, of 0.04918, 0.09367, 0.23797, 0.36365, 0.85923, 1.06930, 1.35223 and 1.81668 mol⋅kg-1 of Ca(CH3COO)2 are reported. The combined expanded uncertainty of the density (ρ) measurements at the 95 % confidence level with a coverage factor of k = 2 was estimated to be Uc(ρ) = ±0.3 kg∙m‐3. The measurements were realized with an Anton Paar DMA HPM vibration tube density meter. The system was calibrated using double-distilled water, aqueous NaCl solutions, methanol, toluene and acetone. An equation of state for fitting of the (p, ρ, T) data of aqueous calcium acetate was developed as a function of pressure, temperature and molality. After a thorough analysis of literature values and validity of the constructed equation of state, various thermophysical properties, such as isothermal compressibility, isobaric thermal expansibility, differences in isobaric and isochoric heat capacities, thermal pressure coefficient and internal pressure at the investigated state parameter intervals were calculated.

(p,ρ,T) data of 1-octyl-3-methylimidazolium tetrafluoroborate [OMIM][BF4] over a wide range of temperatures, from 278.15 to 413.15 K, and pressures, p, up to 140 MPa are reported with an estimated ±0.01–0.08 % experimental relative average percent deviation (APD) in the density. The measurements were performed using an Anton Paar DMA HPM vibration tube densimeter. (p,ρ,T) Data for [OMIM][BF4] was fitted and the parameters of the applied equation were determined as a function of pressure and temperature. After a thorough analysis of literature values and validity of the used equation of state, various thermophysical properties, such as isothermal compressibility, isobaric thermal expansibility, differences in isobaric and isochoric heat capacities, thermal pressure coefficient, internal pressure, heat capacities at constant pressure and volume, speed of sound and isentropic exponent at temperatures in the range 278.15–413.15 K and pressures p up to 140 MPa were calculated.

Pressure, density and temperature (p, ρ, T) data and apparent molar volumes, Vφo, of aqueous calcium acetate solutions Ca(CH3COO)2(aq) over a wide range of temperatures from 273.15 to 353.15 K, pressures up to p = 100 MPa and molalities m, of 0.04918, 0.09367, 0.23797, 0.36365, 0.85923, 1.06930, 1.35223 and 1.81668 mol⋅kg-1 of Ca(CH3COO)2 are reported. The combined expanded uncertainty of the density (ρ) measurements at the 95 % confidence level with a coverage factor of k = 2 was estimated to be Uc(ρ) = ±0.3 kg∙m‐3. The measurements were realized with an Anton Paar DMA HPM vibration tube density meter. The system was calibrated using double-distilled water, aqueous NaCl solutions, methanol, toluene and acetone. An equation of state for fitting of the (p, ρ, T) data of aqueous calcium acetate was developed as a function of pressure, temperature and molality. After a thorough analysis of literature values and validity of the constructed equation of state, various thermophysical properties, such as isothermal compressibility, isobaric thermal expansibility, differences in isobaric and isochoric heat capacities, thermal pressure coefficient and internal pressure at the investigated state parameter intervals were calculated. [ABSTRACT FROM AUTHOR]

Density of eight geothermal and natural water samples from Yardymli District of Azerbaijan have been measured over the temperature range from (274 to 413) K and at pressures up to 100MPa. The measurements were made using the Anton Paar DMA HPM and DSA 5000 M VTD densimeters. The combined expanded uncertainty of the density, pressure, and temperature measurements at the 95% confidence level with a coverage factor of k = 2 is estimated to be (0.01 to 0.03)%, (0.1 to 0.5) %, and 15mK, respectively. For the same geothermal and natural water samples the vapor -pressures were also measured using absolute and differential static, at low temperatures from (274 to 323) K. and absolute static methods at high temperatures from (323 to 413) K. The measured vaporpressures (Ρs-Ts) and single-phase PVT data were used to accurate estimate saturated liquid densities (ρs-Ts) for all studied geothermal and natural water samples using extrapolation technique to complete the high-temperature and high-pressure PVT phase diagram of natural waters. The Riedel's characteristic density constant of the specific ions (ion contribution constants) for main ion species in the natural water samples were estimated on the bases of measured PVT properties. Measured values of density were used to develop equation of state which reproduced the experimental densities within an uncertainty of 0.005% and can be used for engineering calculation of the other important thermodynamic properties such as adiabatic coefficient of bulk compressibility (Ks), isothermal coefficient of bulk compressibility (KT), thermal expansion coefficient (rvp). thermal pressure coefficient (γv), internal pressure (Pint), enthalpy difference (ΔH), entropy difference (ΔS), isochoric heat capacity (Cv), isobaric heat capacity (Cp), and speed of sound (W) of natural waters. The measured values of density of natural waters at atmospheric pressure have been used as a reference data for prediction high-temperature and high-pressure PVT properties. The present high-pressure and high-temperature PVT data for natural waters were used to check and confirm the accuracy, reliability and predictive capability of the predictive methods. [ABSTRACT FROM AUTHOR]

Abstract: The (p, ρ, T) and (p s, ρ s, T s) properties and apparent molar volumes V ϕ of ZnCl2 (aq) at T =(298.15 to 398.15)K, pressures up to p =60MPa were measured by the constant volume piezometer method. Experimental (p, ρ, T) and (p s, ρ s, T s) values were described by an equation of state. The apparent molar volumes of ZnCl2 at infinite dilution V ϕ 0, isothermal compressibilities k and thermal expansivities α have been evaluated. An empirical correlation for apparent molar volumes V ϕ of zinc chloride in water with pressure, temperature and molality has been derived. The experiments were carried out at molalities m =(0.07627, 0.25375, 0.65853, 1.39371, 3.22953, and 7.71336)mol kg−1 of zinc chloride. [Copyright &y& Elsevier]

Abstract: The (p, ρ, T) and (p s, ρ s, T s) properties and apparent molar volumes V ϕ of ZnBr2 (aq) at T = (298.15 to 398.15) K, pressures up to p =60 MPa were reported, and apparent molar volumes of ZnBr2 at infinite dilution V ϕ 0 have been evaluated. The experiments were carried out by the constant volume piezometer installation, (p, ρ, T) and (p s, ρ s, T s) values were described by an equation of state. The isothermal compressibilities k and thermal expansivities α were calculated from the equation of state. An empirical correlation for density of zinc bromide (aq) with pressure, temperature and molality has been derived. The experiments were carried out at molalities m =(0.06220, 0.17341, 0.38183, 0.84419, 1.43444, and 4.18418) mol kg− 1 of zinc bromide. [Copyright &y& Elsevier]

Abstract: (p,ρ,T) and (p s,ρ s,T s) properties and apparent molar volumes V ϕ of CaCl2 (aq) at T=298.15 to 398.15 K, at pressures up to p=60 MPa were reported, and apparent molar volumes at infinite dilution have been evaluated. An empirical correlation for partial molar volumes of calcium chloride in water with pressure, temperature and molality has been derived. The experiments were carried out at molalities m=0.18388, 0.47423, 1.59005, 3.00344, 4.85170, and 6.00687 mol·kg−1 of calcium chloride. [Copyright &y& Elsevier]

The (p,ρ,T) and (ps,ρs,Ts) properties of {(1−x)CH3OH + xLiBr} over a wide range of state parameters are reported for the first time. The experiments were carried out in a constant volume piezometer over a temperature range from 298.15 K to 398.15 K, at 0.08421, 0.13617, 0.19692, 0.23133 and 0.26891 mole fractions and from atmospheric pressure up to 60 MPa. The experimental uncertainties are ΔT=±3 mK for temperature, Δp=±5·10−2 MPa for high pressure and Δp=±5·10−4 MPa for atmospheric pressure, Δρ=±3·10−2 kg · m−3 for density. An equation of state was derived for correlation of the experimental data of the solutions. [Copyright &y& Elsevier]

The (p, ρ, T) properties of {(1−x1−x2)H2O+x1CH3OH+x2LiBr} over a wide range of state parameters are reported for the first time. The experiments were carried out in a constant volume piezometer over a temperature range from 298.15 K to 398.15 K, at x1=0.58302, x2=0.07148; x1=0.31791, x2=0.11693; x1=0.14923, x2=0.05489; x1=0.10425, x2=0.15356; x1=0.04677, x2=0.16341 from atmospheric pressure up to 60 MPa. The experimental uncertainties are ΔT=±3 mK for temperature, ΔP=±5·10−2 MPa for high pressure and ΔP=±5·10−4 MPa for atmospheric pressure, Δρ=±3·10−2 kg·m−3 for density. A equation of state was derived for correlation of the experimental data of solutions. [Copyright &y& Elsevier]