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Densities of pure furan, toluene, 1-octanol, n-hexane and of binary liquid mixtures containing furan, have been measured from 303.15 to 383.15 K at pressures up to 1.6 MPa, using a vibrating tube densimeter. Excess molar volumes have been calculated from the densities with an average standard uncertainty 0.02 cm3⋅mol−1. Excess molar enthalpies of the binary mixtures were measured at temperatures ranging from 313.15 to 383.15 K at 0.5 MPa and/or 1.0 MPa, using flow mixing calorimeter. The average standard uncertainty on the whole measurements is less than 1%. The excess molar properties derived from experimental data were correlated using Redlich–Kister polynomial functions and NRTL activity coefficient model and Prigogine–Flory–Patterson modelling is described and used to correlate the data. [ABSTRACT FROM AUTHOR]

We present an experimental investigation of surface tension–driven sintering and associated densification of glassy rhyolitic ash and crystals under shallow volcanic conduit conditions. Rhyolitic glass (< 45 μm) and quartz were run in suites of hydrothermal experiments for 30 min to 9 h. Fluid pressure was isobaric ( P H 2 O = 40 M P a ) for all runs, and temperature was held constant at a value between 675 and 850 °C. Three size populations of quartz were used: 45–76 µm (fine), 90–125 µm (medium), and 250–500 µm (coarse). All samples evolved from loose, cohesion-less particles to a friable, agglutinated framework of glass with an interconnected network of pores of ≥ 15 vol.%. Samples sintered more slowly at cooler temperatures and with finer crystals relative to higher temperatures or coarser crystals. Compared with previous experiments on glass-only samples, all crystal-bearing samples reached a higher final porosity, and those containing fine and medium crystals also sintered more slowly. Permeability was determined via numerical simulation for one sample and was found to be similar to natural samples with equivalent porosity. Our results suggest that solid particles inhibit the sintering process by holding porous networks open. Sintered magma in the shallow conduit that contains crystal (and lithic) particles can thus experience more sustained degassing and outgassing than crystal-free systems. [ABSTRACT FROM AUTHOR]

A fundamental equation of state expressed explicitly in the Helmholtz energy is presented for R-1224yd(Z), an environmentally friendly refrigerant for centrifugal chillers, high-temperature heat pumps, and organic Rankine cycles. The equation of state is based on consistent experimental data for the critical parameters, vapor pressures, saturated liquid and vapor densities, (p , ρ , T) behavior, vapor-phase sound speeds, liquid-phase sound speeds, and ideal-gas isobaric heat capacities. The equation is valid at temperatures from the triple-point temperature (157.8 K) to 473 K and pressures up to 35 MPa. In the valid range, expected relative uncertainties ( k = 2 ) of the equation are 0.04 % for vapor pressures, 0.1 % for saturated liquid densities, 2 % for saturated vapor densities, 0.05 % for liquid densities, 0.3 % for vapor densities, 0.02 % for vapor-phase sound speeds, and 0.04 % for liquid-phase sound speeds, except in the critical region, where more significant uncertainties of up to 2 % are sometimes observed in densities. The equation exhibits reasonable behavior in the critical and extrapolated regions; this is demonstrated by several plots of derived properties over wide ranges of temperature and pressure. [ABSTRACT FROM AUTHOR]

In this work, the isothermal vapor–liquid equilibrium (VLE) of trans-1,3,3,3-tetrafluoropropene (HFO-1234ze(E)) and 1,1,1,3,3-pentafluoropropane (HFC245fa) binary system, along with the saturated vapor pressures HFO-1234ze(E) and HFC-245fa, were measured by static-analytic apparatus. The VLE measurements of HFO-1234ze(E) + HFC-245fa binary system are performed at temperatures from (293.28 to 333.09) K, while the measurements for vapor pressures of HFO1234ze(E) and HFC-245fa were conducted in the temperature range of (263.08 to 363.01) K. The vapor pressures were correlated by the Peng-Robinson (PR) equation of state (EoS) associated with the Mathias-Copeman (MC) alpha function, and the VLE data were correlated to the PRMC-vdW model where the MC alpha function and the van der Waals (vdW) mixing rules were combined with the PR EoS. The experimental VLE data were compared with the predictive E-PPR78 model. The modeling results of the PRMC-vdW model had good agreement with the experimental VLE data, while the E-PPR78 model shows negative bias in the prediction of equilibrium pressures. The experimental VLE data were also compared with literature data for consistency checks. The two sets of VLE data were basically consistent, while a discrepancy was found when analyzing the relationship between binary interaction parameter kij and temperature. [ABSTRACT FROM AUTHOR]

The relevance of research into the thermophysical properties of lead is associated with the implementation of a BREST-300 reactor project. The enthalpy of solid and liquid lead in the range of 432–1327 K was measured by the mixing method using a massive isothermal calorimeter. The enthalpy of melting was determined. Approximation equations for the temperature dependence of enthalpy in the range of 298.15–1325 K were obtained to determine the isobaric heat capacity. The existence of a heat capacity minimum for liquid lead in the region of 830 K was established. An analysis of existing recommended and experimental data on the caloric properties of lead was performed. The need for new measurements of the enthalpy and heat capacity of a melt at temperatures above 1050 K is substantiated. [ABSTRACT FROM AUTHOR]

This work presents a fundamental equation of state for the thermodynamic properties of R-1336mzz(E). The equation of state is expressed explicitly in the Helmholtz energy with temperature and density as the independent variables, and is based on consistent experimental datasets, including the critical parameters, vapor pressure, saturated liquid and vapor densities, (p , ρ , T) behavior, vapor phase sound speed, and ideal-gas isobaric heat capacity. The equation of state is valid for temperatures from 200.15 K to 410 K and pressures up to 5.7 MPa. In this range, expected relative uncertainties at the 95 % confidence interval ( k = 2 ) are 0.1 % for vapor pressures, 1 % for saturated liquid densities, 1 % for saturated vapor densities, 0.15 % for liquid densities, 0.5 % for vapor densities, and 0.05 % for vapor phase sound speeds, except in the critical region where larger uncertainties of up to 2 % are sometimes observed in densities. The equation exhibits reasonable behavior in the critical and extrapolated regions; this is demonstrated by several plots of derived properties over wide ranges of temperature and pressure. Through the use of the new equation of state, this work also formulates an extended corresponding states (ECS) model for the viscosity and thermal conductivity of R-1336mzz(E) to represent recent experimental data for these properties mostly within their uncertainties. [ABSTRACT FROM AUTHOR]

Murphy and Koop's 2005 equation is used as a standard for vapor pressure in supercooled water. Recently, however, new measurements of molar heat capacity of supercooled water have emerged that both show a more rapid increase in isobaric heat capacity in the supercooled region and penetrate well below the homogeneous nucleation limit. These new data lead to the need to recalculate the saturation vapor pressure in the supercooled region. An equation describing the temperature dependence of the saturation vapor pressure in the temperature interval from 150 K to 273.16 K is presented. [ABSTRACT FROM AUTHOR]

Equations of state for n-hexadecane (C16H34) and n-docosane (C22H46) have been developed as functions of the Helmholtz energy with independent variables of temperature and density. The equations were developed based on experimental values of density, speed of sound, isobaric heat capacity, and vapor pressure. With these equations, all thermodynamic properties of n-hexadecane and n-docosane can be calculated. For n-hexadecane, the uncertainty in vapor pressure is 0.5 %. The uncertainty of the saturated liquid density is 0.05 % from the triple point up to 400 K, and 0.2 % at higher temperatures. The uncertainty in densities is within 0.5 %. The speed of sound and isobaric heat capacity can be calculated within 0.25 %. The uncertainties of the properties calculated with the equation for n-docosane are 5 % for vapor pressure, 0.1 % for saturated liquid density, 1 % for density, 0.5 % and 1 % for speed of sound at atmospheric pressure and higher pressures, respectively, and within 3 % for heat capacity. [ABSTRACT FROM AUTHOR]

A new fundamental equation of state is presented for 2,3,3,3-tetrafluoroprop-1-ene (R1234yf). The equation is valid from the triple point temperature (121.6 K) to 410 K at pressures up to 100 MPa, where typical expanded uncertainties (k = 2) in calculated properties from the equation are 0.1 % for vapor pressures at temperatures above 270 K and 0.3 % at lower temperatures, 0.1 % for liquid densities at pressures below 40 MPa and 0.25 % at higher pressures, 0.2 % for vapor densities, 0.02 % for vapor phase sound speeds, 0.05 % for liquid phase sound speeds, 1 % for vapor phase isobaric heat capacities, 2 % for liquid phase isobaric heat capacities, and 2 % for liquid phase isochoric heat capacities. At very low temperatures around 200 K, uncertainties for vapor pressures may be larger than 0.5 %. Various plots of constant-property lines demonstrate that not only does the equation exhibit correct behavior over all temperatures and pressures within the range of validity, but also that it shows reasonable extrapolation behavior at extremely low and high temperatures, and at high pressures and densities. The equation of state is the best currently available property representation for R1234yf, and has been adopted as an international standard by the ISO working group, which recently revised ISO/DIS 17584 (Refrigerant properties). [ABSTRACT FROM AUTHOR]

Due to the advantages of high temperature stability, low corrosion, and good heat transfer performance, potassium nitrate aqueous solution holds application potential in absorption systems. In order to further improve its absorption ability, ionic liquids (ILS) such as [Emim]Cl, [Emim]Ac, and [Emim]Br were selected as additives. In this paper, vapor pressures of four {KNO3 + ILS + H2O} ternary systems were measured by a dynamic boiling point method, including {KNO3 + [Emim]Cl + H2O}, {KNO3 + [Emim]Ac + H2O}, {KNO3 + [Emim]NO3 + H2O}, and {KNO3 + [Emim]Br + H2O}. Molar ratios between KNO3 and ILs were 1:1 for these systems, and the total absorbent mass fractions were in the range of 0.20 to 0.70. Experimental data were regressed by Antoine-type equations, and the average absolute relative deviations (AARD%) between the experimental and calculated values were no more than 0.78%, which showed good consistency of these experiments. Vapor–liquid equilibrium behavior of these different ionic liquid ternary systems were compared and [Emim]Ac showed best performance in reducing vapor pressure at relatively higher mass fractions. [ABSTRACT FROM AUTHOR]

This work aims to present results of density (ρL), isobaric thermal expansivity coefficient (αP,L) and isothermal compressibility coefficient (kT,L) correlations for n-dodecane and n-nonane as a function of temperature and pressure, able to obtain these properties at any temperature and pressure in the range of 4 °C to 40 °C and 0.1 MPa to 15.0 MPa, with low uncertainties (in the case of n-dodecane: 0.00025 g⋅cm−3 for ρL; 0.00020 °C−1 for αP,L and 0.00022 MPa−1 for kT,L and in the case of n-nonane: 0.00026 g⋅cm−3 for ρL; 0.00006 °C−1 for αP,L and 0.00032 MPa−1 for kT,L). The density measurements were performed using a pycnometer that was calibrated which presents a volume uncertainty of 0.020 cm3. [ABSTRACT FROM AUTHOR]

The present study was carried out in the frame of the optimization of the synthesis process of 1,1,4,4-tetramethyl-2-tetrazene (TMTZ), a prospective liquid propellant. The liquid–liquid (LL) equilibria of the TMTZ + H2O binary system were studied under atmospheric pressure and in the temperature range from 278.15 up to 348.15 K. These results established the conditions leading to a spontaneous demixing of TMTZ from the aqueous synthesis solutions. The experimental study of the liquid–vapor (LV) equilibria of the TMTZ + H2O system using DSC, under atmospheric pressure, highlighted the various equilibrium domains involved in the distillation step. Besides, a heteroazeotropic invariant was identified at TH = 366.3 K for x (TMTZ) = 0.254. Lastly, the thermodynamic modeling of those equilibria, using various models (Van Laar, NRTL, Wilson), enabled to improve the experimental results in order to enhance the extraction conditions leading to the production of ultra-pure TMTZ. [ABSTRACT FROM AUTHOR]

A thermal expansion coefficient (αp) is an essential thermophysical quantity for high pressure research. The thermal expansion coefficient is the volume change over temperature in an isobaric heating process. Although isobaric heating processes for diamond anvil cell (DAC) have been conducted by keeping the pressure constant during heating, pressure determination at high temperature high pressure is debatable for decades long. In this paper, a revertible heating/cooling approach is presented, while its pressure determination at high temperature high pressure is not required. A pressure-dependent thermal expansion coefficient of MgO at 9.5 GPa by revertible heating/cooling was determined by a DAC and its result matches with the one collected by large volume press, whose isobaric heating was conducted by manually adjusting its load/pressure. [ABSTRACT FROM AUTHOR]

The objective of the present study was to investigate the differences in the proteomic profiles of sperm from infertile males with severe oligoasthenoteratozoospermia requiring intracytoplasmic sperm injection (ICSI) and normal control sperm from fertile males. Isobaric tag for relative and absolute quantitation labeling and liquid chromatography–tandem mass spectrometry was performed for identifying proteins in the sperm of infertile and fertile males. Differentially expressed proteins were analyzed via the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases through the Database for Annotation, Visualization, and Integrated Discovery, and protein–protein networks were produced using the Search Tool for Retrieval of Interacting Genes. Immunofluorescence and western blotting verified the differential expression of Y-box-binding protein 1(YBX1), adenylate kinase 1 (AK1), and aconitase 2, mitochondrial (ACO2) proteins. Altogether, 3444 proteins were identified in the sperm of infertile and fertile males, and 938 were differentially expressed between the two groups. Pairwise comparisons revealed that 226 and 712 proteins were significantly upregulated and downregulated in infertile males, respectively. These proteins were significantly enriched in metabolic pathways as per KEGG enrichment analysis. YBX1 expression was upregulated in the sperm heads of patients requiring ICSI treatment, whereas AK1 and ACO2, which are critical enzymes involved in energy metabolism, were downregulated in the sperm tails of the same patients. This result indicates that metabolism may have a crucial role in maintaining normal sperm function. Overall, our results provide insights that will further help in investigating the pathogenic mechanisms of infertility and possible therapeutic strategies. [ABSTRACT FROM AUTHOR]

We report the speeds of sound in liquid toluene (methylbenzene) measured using double-path pulse-echo apparatus independently at The University of Western Australia (UWA) and Imperial College London (ICL). The UWA data were measured at temperatures between (306 and 423) K and at pressures up to 65 MPa with standard uncertainties of between (0.02 and 0.04)%. At ICL, measurements were made at temperatures between (283.15 and 473.15) K and at pressures up to 390 MPa with standard uncertainty of 0.06%. By means of thermodynamic integration, the measured sound-speed data were combined with initial density and isobaric heat capacity values obtained from extrapolated experimental data to derive a comprehensive set of thermodynamic properties of liquid toluene over the full measurement range. Extensive uncertainty analysis was performed by studying the response of derived properties to constant and dynamic perturbations of the sound-speed surface, as well as the initial density and heat capacity values. The relative expanded uncertainties at 95% confidence of derived density, isobaric heat capacity, isobaric expansivity, isochoric heat capacity, isothermal compressibility, isentropic compressibility, thermal pressure coefficient and internal pressure were estimated to be (0.2, 2.2, 1.0, 2.6, 0.6, 0.2, 1.0 and 2.7)%, respectively. Due to their low uncertainty, these data and derived properties should be well suited for developing a new and improved fundamental Helmholtz equation of state for toluene. [ABSTRACT FROM AUTHOR]

Under atmospheric pressure, the density, viscosity and speed of sound of the binary system of octamethylcyclotetrasiloxane (D4) with diesel fuel's main components n-decane, n-dodecane, n-tridecane and n-tetradecane were measured at T = 288.15 to 328.15 K. The excess molar volume, viscosity deviation, excess Gibbs activation energy of viscous flow, isobaric thermal expansivity and isentropic compressibility deviation were calculated from the experimental data. The results indicate that the interactions among mixed systems are somewhat weaker than those in pure components. [ABSTRACT FROM AUTHOR]

Experimental saturated vapor pressure data were measured using a Modified Swietoslawski-type ebulliometer and correlated with the Antoine, Clarke–Glew, and Wagner equations. A least root-mean-square deviation (RMSD) was obtained for the Antoine (0.667) and Wagner (0.796) equations while the group contribution and group interaction (GCGI) method by Nanoolal et al. showed an RMSD of 1.094. The estimated enthalpy of vaporization is found to be 46.87 kJ·mol−1 and 38.56 kJ·mol−1 at reference temperature (298.15 K) and normal boiling point (422.28 K), respectively, and was well verified with Watson's correlation. The critical properties and acentric factor are reported based on the GCGI method. Experimental density data are reported and are well correlated with the DIPPR 116 correlation with an RMSD of 0.00416. Joback's method predicted the densities well with a maximum absolute deviation (MAD) of 0.00548. The Vogel–Tamman–Fulcher equation correlated the experimental viscosities in the temperature range of 288.15–338.15 K with a MAD of 0.002. The isothermal expansivity for tribromomethane shows a linear trend with a weak temperature dependency. [ABSTRACT FROM AUTHOR]

The Bi-Rh binary phase diagram was modelled by CALPHAD approach for the first time. The modelled phase diagram is based mainly on recently published experimental phase diagrams. Very good agreement with the experimental results was reached for the Bi-Rh phase diagram and for the calculated thermodynamic properties, namely the standard enthalpy of mixing of the BiRh phase at 25 °C. [ABSTRACT FROM AUTHOR]

In this work, the new set of the data on the excess heat capacity (CPE), density (ρ) and excess volumes (VE) for binary system n-propanol + water in the temperature range 278.15–358.15 K are presented. The concentration dependence of CPE was correlated using Redlich–Kister equation. Obtained experimental data of CPE were used to calculate excess enthalpies at various temperatures. [ABSTRACT FROM AUTHOR]

The work continues the project of physicochemical characterization of terpenic substances that are present in plants and after emission to the atmosphere play an important role in the formation of cloud condensation nuclei. Two substances, which are solid at room temperature, were studied in this work, namely both enantiomers of menthol and (–)- α -terpineol. Temperatures and enthalpies of fusion were measured, isobaric heat capacities were measured in the temperature range 326.15–348.15 K and vapor pressures were measured in the temperature range 400–430 K. The experimental values were compared with predictions by COSMO-RS. Modern nonstatistical algorithms based on mathematical gnostics were used for data analysis. [ABSTRACT FROM AUTHOR]

The thermodynamic properties of crystalline platinum disulfide have been studied in the range from 5 to 875 K. The isobaric heat capacity of PtS2 has been determined by two methods: by adiabatic calorimetry from 5.32 to 344.96 K and by differential scanning calorimetry in the range 344.6–874.6 K. Using the experimental Cp(T) data, we evaluated the standard thermodynamic functions of platinum disulfide in a wide temperature range. The high-temperature Cp measurement results have been used to investigate regression models based on the Maier–Kelley and Khodakovsky equations for the temperature dependence of its isobaric heat capacity in the range from 298 to 875 K. The Debye characteristic temperature ΘD of PtS2 has been evaluated as a function of temperature. [ABSTRACT FROM AUTHOR]

Solid–liquid-phase equilibrium is an important part of chemical thermodynamics, and its basic theoretical research plays a vital role in the advancement of the chemical industry. Solid–liquid equilibria for binary mixtures of 3-nitrotoluene and 4-nitrotoluene were measured using differential scanning calorimetry under atmospheric pressure (101.3 kPa). The results showed that the phase diagram of the 3-nitrotoluene + 4-nitrotoluene binary system presented a eutectic behavior, and the eutectic point was x1 = 0.6487, TE = 272.15 K. Furthermore, the experimental results were correlated with Wilson and nonrandom two-liquid (NRTL) activity coefficient models well. The relative standard deviations were 0.496 and 0.236, respectively, and the absolute mean deviations were 0.005 and 0.001, respectively. [ABSTRACT FROM AUTHOR]

In the development of CO2 capture and utilization, the physical and transport properties of the binary systems are significant, because these can affect the gas absorption and desorption processes. Thus, we report the densities and viscosities of two binary systems: 2-ethoxyethanol (ECS) + water (H2O) and ECS + dimethyl sulfoxide (DMSO), with various compositions at temperatures from (298.15 to 318.15) K. On the basis of these data, excess molar volumes ( V m E ) and viscosity deviations (Δη) were calculated. The V m E values of the two binary mixtures are negative and decrease with increasing temperatures; Δη values are positive at all compositions and decrease with increasing temperatures. The V m E and Δη values were fitted with the Redlich–Kister equation. The physico-chemical properties of the two binary systems, including activation enthalpy and entropy, were calculated from the kinematic viscosity. In addition, various spectral results offer evidence for the formation of weak interactions between ECS and DMSO or H2O. [ABSTRACT FROM AUTHOR]

The activation Gibbs energies, activation enthalpies and activation entropies reported by the authors were found to be internally inconsistent. Errors were also found in the numerical values of the Redlich–Kister equation coefficients for describing the excess molar volumes and viscosity deviations of both binary systems studied by the authors. [ABSTRACT FROM AUTHOR]

Accurate experimental isobaric densities and viscosities data between 288.15 and 318.15 K at 5 K intervals for five binary liquid mixtures of endo-dicyclopentadiene with 2,2-dimethylbutane, 3-methylpentane, n-hexane, n-heptane and 2,2,4-trimethylpentane are reported. Excess molar volume, VmE, viscosity deviation, Δη, excess Gibbs energy of activation of viscous flow, G*E, have been calculated from these data and fitted by the Redlich-Kister-type equation. Prigogine-Flory-Patterson theory, Eyring-NRTL, Eyring-UNIQUAC, Eyring-Wilson, NRTL, UNIQUAC and Heil models have been applied to the binary systems. [ABSTRACT FROM AUTHOR]

CO adsorption—as a molecular probe—was studied by transmission IR spectroscopy on pre-reduced Pd and bimetallic PdZn nanoparticles. Palladium was supported (2 wt% Pd) on pure CeO2, ZnO and a ZnO-CeO2 composite (atomic ratio Zn:Ce = 1:2). The Pd 3d5/2 binding energy shift, together with the formation of metallic zinc were consistent with the development of a PdZn alloy over the zinc-containing supports at increasing reduction temperature, as revealed by XPS. Following H2 reduction at 623 K the bimetallic particles showed only linear CO adsorption (COL) at initial contact time (10 Torr CO, 298 K), giving rise to a convoluted IR band ascribed to different Pd sites, where it was assumed that the Pd-Pd distances were larger than for pure Pd crystallites, indicating the presence of a PdZn alloyed surface. However, for longer exposure time to CO and/or higher superimposed pressure, the appearance of bridge and hollow coordinated CO (COB and COH, respectively) on the Pd sites suggested the degradation of the PdZn surface alloy, most likely due to the segregation of Pd surface patches. The temperature-programmed, dynamic isobaric adsorption of CO (TPA-CO), under flowing CO(1%)/He on the catalysts pre-reduced at 623 K (that is, for similar conditions to those found in the methanol steam reforming—MSR-process) showed faster desorption of COL as compared to COB + COH species for supported Pd/CeO2, as expected. However, the TPA-CO results on Pd/ZnO-CeO2 were atypical: even under the superimposed, low CO partial pressure, and for a temperature range similar to those found at high methanol conversion in the MSR reaction, the PdZn bimetallic surface nature was recovered, which could be an explanation of the good selectivity to CO2 of Pd/ZnO-based catalysts and—in particular—of the catalytically stable Pd/ZnO-CeO2 materials.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Isobaric interference is a major limitation of secondary ion mass spectrometry. We developed a simple correction method for polyatomic mass interferences from lead in isotope ratio measurements of uranium. Lead-generated isobars were measured to determine their formation rates relative to lead isotopes. The rates were used to mathematically subtract the isobar contributions from the signal intensities in the uranium mass range. The correction method was successfully verified using mixed uranium-lead samples (oxide powder and solution-dried residue). [ABSTRACT FROM AUTHOR]

As an index of the general atmospheric circulation over the hemisphere, it is proposed to calculate the hemisphere-area-averaged (poleward of the latitude 20°) product of the Coriolis parameter by the wind velocity squared at the upper boundary of the planetary boundary layer. In practical calculations, data on the wind velocity at an isobaric level of 850 hPa were used. Control calculations for the 900 hPa level gave similar results. It is shown that the index introduced adequately characterizes the seasonal and interannual variability of the general atmospheric circulation over both hemispheres. [ABSTRACT FROM AUTHOR]

Streamline simulation is a powerful tool that can be used for full field forecasting, history matching, flood optimization, and displacement visualization. This paper presents the development and the application of a new semi-analytical streamline simulation method in the near-wellbore region in polar/cylindrical coordinate systems. The main objective of this paper is to study the effects of the permeability heterogeneity and well completion details in the near-wellbore region. These effects dictate the streamline geometries, which in turn influence well productivity. Previous streamline applications used a constant flow rate for each stream tube. In this paper, streamline simulation is performed under the assumption of constant pressure boundaries, which is a novel and non-trivial extension of streamline simulation. Solutions are constructed by treating each stream tube as a flow unit by invoking analytical solutions for such geometries. In addition, visualization experiments are conducted to investigate the effect of the heterogeneity. Two-dimensional waterflooding visualization experiments in radial porous media are performed with constant pressure boundaries. The streamline simulator is applied to history match the relative permeabilities using these experiments, thereby validating the new near-well streamline method. [ABSTRACT FROM AUTHOR]

In this work, we investigate the time evolution of a massless scalar perturbation around small and large $\text{RN-AdS}_{4}$ black holes for the purpose of probing the thermodynamic phase transition. We show that below the critical point the scalar perturbation decays faster with increasing of the black hole size, both for small and large black hole phases. Our analysis of the time profile of quasinormal mode reveals a sharp distinction between the behaviors of both phases, providing a reliable tool to probe the black hole phase transition. However at the critical point $P=P_{c}$ , as the black hole size extends, we note that the damping time increases and the perturbation decays faster, the oscillation frequencies raise either in small and large black hole phase. In this case the time evolution approach fails to track the $\text{AdS}_{4}$ black hole phase. [ABSTRACT FROM AUTHOR]

A qualitative description of the most accurate experimental differential cross sections of the reaction γ p→η′ p from the CLAS 2009 Collaboration and unprecedentedly accurate total cross sections of this reaction, measured by the A1 Mainz 2015 Collaboration in the isobaric model of photoproduction has been obtained. Masses and widths of four resonances, extracted from such fits, lay claim to a real existence and lie in the usual mass and width intervals of nucleon resonances. But in order for our model not to contradict the results of measurements of the Σ-asymmetry of this reaction made by the GRAAL 2013 Collaboration, the need arose for an additional resonance with mass equal to the threshold of the reaction under discussion, and width Γ = 110 MeV. [ABSTRACT FROM AUTHOR]

The thermodynamics of association of fullerene [ $$\hbox {C}_{60}$$ ] and water-soluble fullerene derivatives, i. e., fullerols [ $$\hbox {C}_{60}\hbox {(OH)}_{\mathrm{n}}$$ , where, n = 2, 4, 8, 12] in aqueous solutions have been studied using molecular dynamics simulations. The potentials of mean force (PMFs) bring out the tendency of aggregation of these nanostructures in water. The extent of hydroxylation seems to have a minor effect on the depth of the contact minima (the first minimum in the PMFs). The positions of the subsequent minima and maxima in the PMFs change with the size of the solute molecules. Higher stability of the contact state of highly hydroxylated fullerols is due to the van der Waals interactions whereas intermolecular solute-solvent hydrogen bonding nearly flattens the PMFs beyond the $$2{\mathrm{nd}}$$ minima for higher fullerols. The solvent contributions to the PMFs for all the solute particles studied here are positive. Entropic and enthalpic contributions to the association of solute molecules are calculated in the isothermal-isobaric (NPT) ensemble. We find that the contact pair formation is governed by entropy with the enthalpic contributions being highly unfavorable, whereas the solvent assisted and solvent separated configurations show entropy-enthalpy compensation. Graphical Abstract: : Synopsis: Aqueous solutions of fullerene have found applications in molecular sensing devices, biochemistry and environmental science. Therefore, it is necessary to have a microscopic understanding of the solvation structure of such macromolecules. Association and dynamics of fullerene and fullerols [ $$\hbox {C}_{60}\hbox {(OH)}_{\mathrm{n}}$$ ] in water are addressed by molecular dynamics simulations. [ABSTRACT FROM AUTHOR]

One of today's challenges in reservoir management of liquid-rich shales is to accurately forecast production performance based on pressure/rate transient analyses. The need for large pressure gradients to produce from shale reservoirs through multifractured horizontal wells (MFHWs) may induce considerable changes in rock and fluid properties that can largely affect transient bottom-hole pressure response which can result in inaccurate predictions for well performance. Therefore, the assumption of constant properties in shale reservoirs may not be safe when modeling MFHW performance. This paper presents a nonlinear analytical MFHW performance model for single-phase systems based on the five-region model (Stalgorova and Mattar in SPE Reserv Eval Eng 16(03):246-256, 2013) that accounts for pressure-dependent rock and fluid properties in liquid-rich shales. Properties are assumed to vary exponentially with pressure. Because of this, the resulting nonlinear diffusivity equation is linearized by means of an exponential transformation. The nonlinear MFHW performance model is benchmarked against numerical simulation data for a number of case studies. The proposed analytical solution is able to accurately capture transient bottom-hole pressure response while delivering a highly accurate estimation of depletion time. In this study, it was found that nonlinear diffusion processes in liquid-rich shales, under the assumption of exponential changes in properties with pressure, are fully described by the porous medium equation (PME). The PME is presented along with a straightforward application to identify and forecast flow regimes in the reservoir (fast, normal or slow diffusion). Finally, a brief review on diagnostic plots for systems with pressure-dependent properties concludes this work. [ABSTRACT FROM AUTHOR]

This is the second in a series of two papers that presents an updated fluorescence model and compares with the new experimental data reported in the first paper, as well as the available literature data, to extend the range of acetone photophysics to elevated pressure and temperature conditions. This work elucidates the complete acetone photophysical model in terms of each and every competing radiative and non-radiative rate. The acetone fluorescence model is then thoroughly examined and optimized based on disparity with recently conducted elevated pressure and temperature photophysical calibration experiments. The current work offers insight into the competition between non-radiative and vibrational energy decay rates at elevated temperature and pressure and proposes a global optimization of model parameters from the photophysical model developed by Thurber (Acetone Laser-Induced Fluorescence for Temperature and Multiparameter Imaging in Gaseous Flows. PhD thesis, Stanford University Mechanical Engineering Department, 1999). The collisional constants of proportionality, which govern vibrational relaxation, are shown to be temperature dependent at elevated pressures. A new oxygen quenching rate is proposed which takes into account collisions with oxygen as well as the oxygen-assisted intersystem crossing component. Additionally, global trends in ketone photophysics are presented and discussed. [ABSTRACT FROM AUTHOR]

A new device is designed: it consists of a nanocell (NC) filled with Rb atom vapors and placed in a vacuum chamber. When the pressure in the chamber changes in the range 0-1 atm, the NC thickness is smoothly varied in the range L = 140-1700 nm, which is caused by the pressure-induced deformation of thin garnet windows in the chamber. The pressure dependence has excellent reproducibility even after many hundreds of cycles of letting in of air and its complete pumping out from the chamber. The accuracy of setting required thickness L is much better than in the wedge-gap NCs to be moved mechanically that were used earlier. The processes of Faraday rotation (FR) of a polarization plane, resonance absorption, and fluorescence are studied using the D -line narrow-band continuous laser radiation when the thickness changes from L = λ/2 (398 nm) to L = 2λ (1590 nm) at a step λ/2. The FR signal is shown to be maximal at L = λ/2 and 3λ/2 and to have the minimum spectral width (≈60 MHz). At L = λ and 2λ, the FR signal is minimal and has the maximum spectral width (≈200 MHz). The resonance absorption demonstrates the same oscillating behavior; however, the effect in the case of FR is much more pronounced. The oscillating effect is absent for resonance fluorescence: its spectral width and amplitude increase monotonically with L. The detected effects are explained and possible applications are noted. [ABSTRACT FROM AUTHOR]

A model of pion photoproduction on nuclei with emission of two nucleons that takes account of the spectator mechanism of knockout of an isobar produced in the nucleus at the virtual transition NN → ∆N in the ground state of the nuclei is presented. An analysis of experimental data for the reaction C( γ, π p) at large momentum transfers is performed. [ABSTRACT FROM AUTHOR]

In this work, we utilize the quasinormal modes (QNMs) of a massless scalar perturbation to probe the Van der Waals-like small and large black holes (SBH/LBH) phase transition of charged topological Anti-de Sitter (AdS) black holes in four-dimensional massive gravity. We find that the signature of this SBH/LBH phase transition is detected in the isobaric as well as in the isothermal process. This further supports the idea that the QNMs can be an efficient tool to investigate the thermodynamical phase transition. [ABSTRACT FROM AUTHOR]

Two binary phase diagrams of the systems Ag-In and Cu-In were investigated using powder X-ray diffraction (XRD), differential scanning calorimetry (DSC), and electron probe microanalysis (EPMA). The results showed six stable intermediate phases for Cu-In and three for Ag-In and the conditions in which they occur have been precisely defined. [ABSTRACT FROM AUTHOR]

The isobaric heat capacity of molten eutectic mixtures LiCl-CsCl, LiCl-KCl-CsCl, LiBr-KBr, LiBr-CsBr and LiBr-KBr-CsBr was measured at temperatures not above 150 K above melting point using differential scanning calorimetry. The molar heat capacity of all mixtures under study was found to be close to that of pure salts in a molten state. The excess heat capacity is proportional to the negative enthalpy of mixing. [ABSTRACT FROM AUTHOR]

We performed an in situ dehydroxylation kinetics study of brucite under water-saturated conditions in the pressure and temperature ranges of 593-633 K and 668-1655 MPa using a hydrothermal diamond anvil cell. The kinetic analysis of the isothermal-isobaric data using an Avrami-type model involving nucleation and growth processes yields values for the dehydroxylation rate and reaction order compatible with a reaction mechanism limited by the monodimensional diffusion of water molecules from structural OH groups. Our results show a negative pressure dependence on the reaction rate k and a positive temperature dependence on the k. The dehydroxylation of brucite yields an activation volume ∆ V value of 5.03 cm/mol. Following the Arrhenius relationship, the apparent activation energy E of the process is calculated to be 146 kJ/mol within the experimental P- T ranges. It is determined that the fluid production rates varying from 4.4 × 10 to 10.7 × 10 $${\text{m}}_{\text{fluid}}^{3} \;{\text{m}}_{\text{rock}}^{ - 3} \;{\text{s}}^{ - 1}$$ are a few orders of magnitude greater than the strain rate of the mantle serpentinites, which may be fast enough to result in the brittle fracture of rocks. Moreover, the rate of fluid production will be enhanced when brucite occurs in the non-/low HO environments of the subduction zone. [ABSTRACT FROM AUTHOR]

The development and validation of a grid-based pore-scale numerical modelling methodology applied to five different commercial metal foam samples is described. The 3-D digital representation of the foam geometry was obtained by the use of X-ray microcomputer tomography scans, and macroscopic properties such as porosity, specific surface and pore size distribution are directly calculated from tomographic data. Pressure drop measurements were performed on all the samples under a wide range of flow velocities, with focus on the turbulent flow regime. Airflow pore-scale simulations were carried out solving the continuity and Navier-Stokes equations using a commercial finite volume code. The feasibility of using Reynolds-averaged Navier-Stokes models to account for the turbulence within the pore space was evaluated. Macroscopic transport quantities are calculated from the pore-scale simulations by averaging. Permeability and Forchheimer coefficient values are obtained from the pressure gradient data for both experiments and simulations and used for validation. Results have shown that viscous losses are practically negligible under the conditions investigated and pressure losses are dominated by inertial effects. Simulations performed on samples with varying thickness in the flow direction showed the pressure gradient to be affected by the sample thickness. However, as the thickness increased, the pressure gradient tended towards an asymptotic value. [ABSTRACT FROM AUTHOR]

High temperature (1 270-1 550 ºC) and high pressure (1.0 GPa) experimental studies on Re-bearing capabilities of pyrite, galena and sphalerite from typical Pb-Zn ore deposits were performed on a six-anvil apparatus. We observed microstructures of the quenched sulfides using scanning electron microscope (SEM) and analyzed compositions of the run products using both energy disperse spectroscopy (EDS) and electron probe microanalyzer (EPMA). The results show that pyrite melt can dissolve much more metallic Re than galena and sphalerite melts, forming scattered acicular ReS in the quenched matrix of pyrrhotite (FeS). The quenched matrixes of FeS, PbS and ZnS generally contain less than 1.0 wt.% of Re and their Re-bearing capabilities seem to range as FeS>PbS>ZnS. However, Re partition coefficients between them are difficult to estimate, because Re distribution is inhomogeneous in the quenched sulfide matrixes. [ABSTRACT FROM AUTHOR]

Dynamic impact tests are performed on prismatic marble specimens containing a single flaw using a modified split-Hopkinson pressure bar device. The effects of pre-existing flaws with different flaw angles and lengths on the dynamic mechanical properties are analyzed. The results demonstrate that the dynamic strength of marble is influenced by the flaw geometry. The dynamic fracturing process of flawed specimens is monitored and characterized with the aid of a high-speed camera. Cracking of marble specimens with a single pre-existing flaw under impact loading is analyzed based on experimental investigations. Cracking involves two major stages: formation of white patches and development of macrocracks. Six typical crack types are identified on the basis of their trajectories and initiation mechanisms. The presence of an artificial flaw may change the failure mode of marble from splitting-dominated for an intact specimen to shear-dominated for a flawed specimen under dynamic loading. Nevertheless, the geometry of the flaws appears to have a slight influence on the failure modes of flawed specimens under impact loading. [ABSTRACT FROM AUTHOR]

Apoptosis suppression caused by overexpression of anti-apoptotic proteins is a central factor to the acquisition of multi-drug resistance (MDR) in breast cancer. As a highly conserved anti-apoptotic protein, Bcl-2 can initiate an anti-apoptosis response via an ERK1/2-mediated pathway. However, the details therein are still far from completely understood and a quantitative description of the associated proteins in the biological context may provide more insights into this process. Following our previous attempts in the quantitative analysis of MDR mechanisms, liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based targeted proteomics was continually employed here to describe ERK/Bcl-2-mediated anti-apoptosis. A targeted proteomics assay was developed and validated first for the simultaneous quantification of ERK1/2 and Bcl-2. In particular, ERK isoforms (i.e., ERK1 and ERK2) and their differential phosphorylated forms including isobaric ones were distinguished. Using this assay, differential protein levels and site-specific phosphorylation stoichiometry were observed in parental drug-sensitive MCF-7/WT cancer cells and drug-resistant MCF-7/ADR cancer cells and breast tissue samples from two groups of patients who were either suspected or diagnosed to have drug resistance. In addition, quantitative analysis of the time course of both ERK1/2 and Bcl-2 in doxorubicin (DOX)-treated MCF-7/WT cells confirmed these findings. Overall, we propose that targeted proteomics can be used generally to resolve more complex cellular events. [ABSTRACT FROM AUTHOR]

Traditional definitions of seasonality are insufficient to reflect changes associated with a swiftly changing climate. Regional changes in season onset and length using surface based metrics are well documented, but hemispheric assessments using tropospheric metrics has received little attention. The long-term average of six-hourly analyses of temperature on isobaric surfaces, provided by the Twentieth Century Reanalysis Project, is separated here into quartiles to determine climatologic seasonal end dates. Annual season end dates are defined as the date when the 5-day moving average rose above (winter and spring) or fell below (summer and fall) the long term mean. Climatic season end dates fall between meteorological and astronomical season end dates. The length of summer has increased by an average of 13 days and the length of winter has decreased by an average of 20 days, which are more substantial seasonal changes than previous studies. These changes in season length have occurred largely within the past 36 years, corresponding to most aggressive anthropogenic climate change. Results show that the planetary boundary layer is warming at nearly twice the rate of the free troposphere. The spatial distribution of warming suggests that topographically induced weather systems are collocated with maxima or minima in free tropospheric and boundary layer temperature slope. Furthermore, regions of greatest ensemble spread are not collocated with relative maxima or minima in free troposphere or boundary layer temperature slope. This improved assessment of seasonal transitions is useful to climatologists, agricultural land managers, and scientists interested in seasonally driven biology, hydrology and biogeochemical processes. [ABSTRACT FROM AUTHOR]

The results based on the spectroscopy of superheavy hydrogen isotopes (H), heavy helium isotopes (He), and heavy lithium isotopes (Li) produced in stopped pion absorption by light nuclei were analyzed. Search for nuclear states was performed in inclusive and correlation measurements of missing mass spectra. A broad range of excitation energies studied in correlation measurements provided the possibility of search for isobaric analog states and cluster resonances. A comparison with experimental and theoretical results of other authors was conducted. [ABSTRACT FROM AUTHOR]

The values of interatomic separation r with the change of temperature T for seven alkali halides have been investigated with the help of an isobaric equation of state. The calculated results are used to predict the values of bulk modulus at different temperatures. The results are compared with the available experimental data and other theoretical results and are further discussed in view of recent research in the field of high temperature physics. [ABSTRACT FROM AUTHOR]

The article discussed 10 reasons to be more attentive to patients when setting the ventilator. It mentioned that mechnical ventilaton is a form of externally assisted ventilation that delivers positive pressure throughout the respiratory cycle. It further discussed the reasons including to find the optimal flow rate adjustment, to eliminate double-triggering and to appropriately adjust the dose of ventilation.

Pressure swing adsorption of nitrogen onto granular activated carbon in the single-bed adsorber-desorber chamber has been studied at six different pressures 6-18 kgf/cm to evaluate their performance as an alternative refrigeration technique. Refrigerating effect showed a linear rise with an increase in the operating pressure. However, the heat of adsorption and COP exhibited initial rise with the increasing operating pressure but decreased later after reaching a maximum value. The COP initially increases with operating pressures however, with the further rise of operating pressure it steadily decreased. The highest average refrigeration, maximum heat of adsorption and optimum coefficient of performance was evaluated to be 415.38 W at 18 kgf/cm, 92756.35 J at 15 kgf/cm and 1.32 at 12 kgf/cm, respectively. The system successfully produced chilled water at 1.7 °C from ambient water at 28.2 °C. [ABSTRACT FROM AUTHOR]

Background: We performed a discovery phase of urinary proteomic profile in children with idiopathic nephrotic syndrome and validated selected biomarkers. Methods: Urinary proteomic profile was performed using isobaric tags for relative and absolute quantitation labeling, coupled with liquid chromatography-matrix assisted laser desorption and ionization analysis. Validation of biomarkers apolipoprotein A1, alpha 2 macroglobulin, orosomucoid 2, retinol binding protein 4 and leucine-rich alpha 2-glycoprotein 1 was done by enzyme-linked immunosorbent assay. Results: Apolipoprotein A1 levels of <0.48 µg/mg of creatinine-differentiated steroid-resistant nephrotic syndrome (SRNS) from first episode nephrotic syndrome, area under curve (AUC) [0.99 (CI 0.9-1.0), 100 % sensitivity and 100 % specificity] and a value of <0.24 µg/mg of creatinine could differentiate SRNS from frequently relapsing nephrotic syndrome/steroid dependent nephrotic syndrome [AUC 0.99 (CI 0.9-1.0), 100 % sensitivity and 100 % specificity]. Alpha 2 macroglobulin could differentiate children with SRNS-focal segmental glomerulosclerosis (FSGS) from SRNS-minimal change disease (MCD) at values >3.3 µg/mg of creatinine [AUC 0.84 (CI 0.62-1.0), 90 % sensitivity and 85 % specificity]. Orosomucoid 2 >1.81 µg/mg of creatinine could distinguish SRNS-FSGS from SRNS-MCD [AUC 0.84 (CI 0.62-1.0), sensitivity 90 % and specificity 85.5 %]. RBP 4 value of >1.54 µg/mg of creatinine differentiated SRNS-FSGS from SRNS-MCD [AUC 0.87 (CI 0.68-1.0), sensitivity 90 % and specificity 85.7 %]. Conclusions: Lower level of apolipoprotein A1 in urine is suggestive of SRNS. Alpha 2 macroglobulin, retinol binding protein 4 and orosomucoid 2 are markers associated with FSGS, with alpha 2 macroglobulin being most predictive. [ABSTRACT FROM AUTHOR]