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We present a new extended parametric equation-of-state model for thermodynamic properties and the correlation length for a simple fluid near its liquid–gas critical point. The model involves 16 universal parameters to perfectly match 10 leading universal amplitudes of the asymptotic Ising-like limit of the critical-to-classical crossover functions calculated by Garrabos and Bervillier [Phys. Rev. E 74,021113 (2006)] from the massive renormalization scheme. The universal values of 8 Ising-like amplitude combinations are then matched exactly. The closure of the construction of parameters is determined after a careful analysis of the intrinsic limitation of parametric equations to describe the universal features at the first order of the confluent corrections-to-scaling. In the asymptotic mean-field limit, the crossover master model also reproduces the mean-field amplitude combinations except for the susceptibility case. The new model is compared with the crossover parametric model previously developed by Agayan et. al [Phys. Rev. E 64, 02615 (2001)]. The residuals from comparison with the mean crossover functions of Garrabos and Bervillier are reported to define the application range of the crossover master model to any simple fluid for which the generalized critical coordinates of the liquid–gas critical point are known. [ABSTRACT FROM AUTHOR]

Horizontal wells are often drilled and hydraulically fractured in tight reservoirs to produce hydrocarbons or heat. Different fracturing fluids such as slick water, gas, foam, gel, or a combination can be used with slick water being the most common fracturing fluid. In this paper, we study the impacts of different fracturing fluids on fractured well productivity using an in-house integrated hydraulic fracturing and reservoir simulator with an equation-of-state compositional model. We analyzed the fracture geometry, stress interference, proppant placement, and the subsequent well productivity using different fracturing fluids. The results clearly show that different fracturing fluids result in very different fracture shape, sand distribution, and water and hydrocarbon production. By conducting fracturing and production simulations in one simulator, we ensure that no physics and data loss occurs due to data migration between two different software packages for hydraulic fracturing and reservoir simulation. To the best of the authors' knowledge, this is the first time that a single integrated equation-of-state compositional hydraulic fracturing and reservoir simulator has been presented and applied for well lifecycle simulation. [ABSTRACT FROM AUTHOR]

Two natural CO-rich cordierite samples (1.00 wt% CO, 0.38 wt% HO, and 1.65 wt% CO, 0.15 wt% HO, respectively) were investigated by means of Raman spectroscopy and single-crystal X-ray diffraction at ambient and high pressures. The effect of heavy-ion irradiation (Au 2.2 GeV, fluence of 1 × 10 ions cm) on the crystal structure was investigated to characterize the structural alterations complementary to results reported on hydrous cordierite. The linear CO molecules sustained irradiation-induced breakdown with small CO-to-CO conversion rates in contrast to the distinct loss of channel HO. The maximum CO depletion rate corresponds to ~12 ± 5 % (i.e. ~0.87 and ~1.49 wt% CO according to the two samples, respectively). The elastic properties of CO-rich cordierite reveal stiffening due to the CO molecules (non-irradiated: isothermal bulk modulus K = 120.3 ± 3.7 GPa, irradiated: K = 109.7 ± 3.7 GPa), but show the equivalent effect of hydrous cordierite to get softer when irradiated. The degree of anisotropy of axial compressibilities and the anomalous elastic softening at increasing pressure agrees with those reported for hydrous cordierite. Nevertheless, the experimental high-pressure measurements using ethanol-methanol reveal a small hysteresis between compression and decompression, together with the noticeable effect of pressure-induced over-hydration at pressures between 4 and 5 GPa. [ABSTRACT FROM AUTHOR]

The dynamical system of multiple scalar fields in FRW universe with different spatial curvature have been analyzed in this paper. In the radiation-dominated phase, the constant curvature factor k does not work on the cosmic dynamical behaviors, including the scaling solution, energy density parameter and equation-of-state parameter. These aspects are affected by curvature factor k in the matter-dominated phase. In the special scalar field-dominated phase, the energy density parameter normalization restricts the Universe is spatial flat and the curvature factor k is not present in the dynamics. In this paper, the Universe is closed in the matter-dominated phase, and flat in the scalar field-dominated phase. The spatial flatness and the w=−1 in the third phase are coincide with the current observations. [ABSTRACT FROM AUTHOR]

The equation of state of MgGeO3 perovskite was determined between 25 and 66 GPa using synchrotron X-ray diffraction with the laser-heated diamond anvil cell. The data were fit to a third-order Birch–Murnaghan equation of state and yielded a zero-pressure volume ( V 0) of 182.2 ± 0.3 Å3 and bulk modulus ( K 0) of 229 ± 3 GPa, with the pressure derivative ( K′0 = ( ∂K 0/ ∂P) T ) fixed at 3.7. Differential stresses were evaluated using lattice strain theory and found to be typically less than about 1.5 GPa. Theoretical calculations were also carried out using density functional theory from 0 to 205 GPa. The equation of state parameters from theory ( V 0 = 180.2 Å3, K 0 = 221.3 GPa, and K′0 = 3.90) are in agreement with experiment, although theoretically calculated volumes are systematically lower than experiment. The properties of the perovskite phase were compared to MgGeO3 post-perovskite phase near the observed phase transition pressure (∼65 GPa). Across the transition, the density increased by 2.0(0.7)%. This is in excellent agreement with the theoretically determined density change of 1.9%; however both values are larger than those for the (Mg,Fe)SiO3 phase transition. The bulk sound velocity change across the transition is small and is likely to be negative [−0.5(1.6)% from experiment and −1.2% from theory]. These results are similar to previous findings for the (Mg,Fe)SiO3 system. A linearized Birch–Murnaghan equation of state fit to each axis yielded zero-pressure compressibilities of 0.0022, 0.0009, and 0.0016 GPa−1 for the a, b, and c axis, respectively. Magnesium germanate appears to be a good analog system for studying the properties of the perovskite and post-perovskite phases in silicates. [ABSTRACT FROM AUTHOR]

The equation of state of a quasi one-dimensional model lipid monolayer is obtained in analytic form. The method used is the Laplace transform approach leading to a homogeneous Fredholm integral equation. Two cases are studied. The first considers a purely short range repulsive potential, when we recover the results previously obtained by Gianotti et al. (J. Phys. A.: Math. Gen.25:2889 (1992)). The second incorporates the long range attractive Kac potential, and the equation of state is calculated in the van der Waals limit. This extends the approach originally developed by Kac et al. (J. Math. Phys.4:216 (1963)). [ABSTRACT FROM AUTHOR]

Shock wave data for Jilin ordinary chondrite and Nandan iron meteorite are measured by electric-pin techniques on the dynamic high-pressure device equipped with a two-stage light gas gun, and then equation-of-states supposedly fit for describing their P- V-E relations are chosen to evaluate the values of their parameters. Demonstrated from the comparison between P-V curves of equation-of-states and experimental data points, P-V relation of Jilin ordinary chondrite can be described by the universal equation-of-state, of which bulk modulus value of zero-pressure Kos = 48.10 GPa, its pressure derivative K’ os = 4.13. That of Nandan iron meteorite can be described by the three-term form of equation-of-state, of which the values of two matter parameters Q = 41.235 31 GPa, q = 12. 27179. The Hugoniot data and equation-of-states for Jilin ordinary chondrite and Nandan iron meteorite are first reported in this paper. The equation-of-state defined by Hugoniot data measurement provides strong empirical support for describing the compression of meteorites to high pressure. [ABSTRACT FROM AUTHOR]

The virial equation of state was determined for helium, xenon, and helium-xenon mixtures for the pressure and temperature ranges 0.5 to 5 MPa and 210 to 400 K. Two independent experimental techniques were employed: Burnett Pρ T measurements and speed-of-sound measurements. The temperature-dependent second and third density virial coefficients for pure xenon and the second and third interaction density virial coefficients for helium-xenon mixtures were determined. The present density virial equations of state for xenon and helium-xenon mixtures reproduce the speed-of-sound data within 0.01% and the Pρ T data within 0.02% of the pressures. All the results for helium are consistent, within experimental errors, with recent ab initio calculations, confirming the accuracy of the experimental techniques. [ABSTRACT FROM AUTHOR]

High-pressure crystal structure refinements and axial compressibilities have been determined by x-ray methods for the olivine isomorph chrysoberyl, AlBeO. Unlike silicate olivines, which are more than twice as compressible along b than along a, chrysoberyl (space group Pbnm) has nearly isotropic compressibility with β=1.12±0.04, β=1.46±0.05, and β=1.31±0.03 (all×10 kbar). The resultant bulk modulus is 2.42±0.05 Mbar, with K′ assumed to be 4. The axial compression ratios of chrysoberyl are 1.00:1.30:1.17, compared to axial compression ratios 1.00:2.02:1.60 for forsterite. These differences in compression anisotropy arise from differences in relative bond compressibilities. In chrysoberyl the average aluminum-oxygen and beryllium-oxygen bond compressibilities are similar, yielding nearly isotropic compression, but in silicate olivines octahedral cation-oxygen bonds are significantly more compressible than Si-O bonds, so that compression parallel to a is much more restricted than that parallel to b. The inherent anisotropy of the olivine structure is not, by itself, sufficient to cause anisotropic compression. It appears that in the case of olivine the distribution of cations of different valences, in conjunction with the structure type, leads to anisotropies in physical properties. [ABSTRACT FROM AUTHOR]

Using argon as the exemplary fluid, we report a representation of equations-of-state in fluid regions bounded by percolation loci with mainly physical constants that define state bounds and characterize the fluid phase diagram. Both gas- and liquid-state pressures can be represented by 3- or 4-term virial expansions. Gaseous states require only known virial coefficients and physical constants belonging to the fluid, i.e., Boyle temperature (TB), Tc, pc and coexisting densities of gas (ρcG) and liquid (ρcL) at Tc. A notable finding is that for isotherms below TB, the contribution of the fourth virial term is negligibly small within experimental uncertainty. In the supercritical mesophase, both gaseous and liquid states percolate the configurational phase volume, whereupon state functions of the density obey a linear combination equation-of-state in this region. We also find evidence for the percolation line that bounds the low-temperature existence of the pure liquid argon state giving rise to an equilibrium prefreezing mesophase. In this region, which probably exists for all liquids, there is a colloidal dispersion of the metastable crystalline structure with an energy density closest to that of the liquid, wherein coexisting amorphous and crystalline states both percolate the phase volume. We report equations-of-state for isotherms of argon, over the whole equilibrium fluid range; i.e., for four regions, gas, supercritical mesophase, liquid, and a liquid + bcc prefreezing and metastable fluid mesophase up to a glass transition pressure. We compare with experiment using the Tegeler–Span–Wagner equation via the NIST fluid thermophysical property database. [ABSTRACT FROM AUTHOR]