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Solubility of CO 2 in ionic liquids (ILs) is of great importance in absorption refrigeration system as new working pairs. Vapor-liquid equilibrium (VLE) of CO 2 in [BMP][Tf 2 N] (1-butyl-1-methyl-pyrrolidine bis(trifluoromethylsulfonyl)imide) is carried out experimentally using the experiment system at temperature range 303.15 K-363.15 K. The experimental results show that the solubility of CO 2 in [BMP][Tf 2 N] can reach up to 0.1235–0.5324 (molar fraction) within temperature range 283.15∼363.15 K and pressure range of 0.2∼5 MPa. The solubility of CO 2 in [BMP][Tf 2 N] increases with increase of temperature and pressure. The VLE data of CO 2 -[BMP][Tf 2 N] binary system is correlated with two models (SRK equation of state +WS mixing rule +UNIFAC activity coefficient model and PR equation of state +WS mixing rule +UNIFAC activity coefficient model). The excess Gibbs free energy (GE), excess enthalpy (HE) and excess entropy (SE) of the system are obtained and the interaction parameters k ij is regressed based on the VLE of CO 2 -[BMP][Tf 2 N] binary system. The variation trend of GE, HE and SE are obtained with temperature, pressure and molar fraction of CO 2. The calculation results show that the accuracy of SRK equation of state is slightly higher than that of PR equation of state in CO 2 -[BMP][Tf 2 N] binary system. The accuracy of SRK equation of state and PR equation of state decreases with increase of temperature and pressure. [ABSTRACT FROM AUTHOR]

Pressure and temperature induced valence changes in the Kondo insulator SmB 6 have been investigated using x-ray absorption spectroscopy (XAS) along several isobaric cooling runs and one isothermal compression. The average valence of Sm at various pressure and temperature conditions is extracted from high quality XAS data by peak fitting procedures. The temperature dependence of the Sm valence at ambient pressure shows changes of slope near the known characteristic temperatures of gap formation (120 K) and the in-gap state (50 K). At higher pressures the average valence also shows similar temperature dependent trends upon cooling but the slope changes are less pronounced. This behavior is discussed in relation to the possible existence of an underlying first order valence transition and its critical end point. At constant temperature (T = 20 K), the Sm valence increases rapidly with pressure; however, it remains far below the expected integer value (3+) near the onset of the magnetic ordering and gap closure. In addition, the local structure of SmB 6 at ambient conditions has been analyzed using extended x-ray absorption fine structure. • Pressure effects on the temperature dependence of Sm valence have been investigated. • Indications of a possible correlation between Kondo insulating behavior and critical valence fluctuations in SmB 6 have been observed. • Local structure of SmB 6 has been investigated using EXAFS refinements. [ABSTRACT FROM AUTHOR]

• Density measurements were conducted for the mixture of 1-butanol and two biodiesels under high-pressure conditions (up to 100 MPa). • Excess volumes were calculated for the blend of 1-butanol + biodiesel. • Correlation with the Tammann-Tait equation was performed, and derived properties were calculated. • Thermodynamic modeling was carried out using the PC-SAFT equation of state. Biodiesel, derived from renewable sources, offers advantages like biodegradability and compatibility with diesel engines. However, high production costs and low-temperature viscosity issues must be addressed. This could be mitigated by blending biodiesel with medium-chain alcohols. This study aims to assess the volumetric properties of the 1-butanol + biodiesel system under high-pressure conditions (0.1 – 100 MPa) and various temperatures (293.15 – 373.15 K) using a DMA HPM device from Anton Paar. Integrating experimental and modeling approaches, we applied equations to obtain derived properties and correlate density data. Equations such as Tammann-Tait and PC-SAFT were applied to the experimental data, yielding maximum mean absolute percentage deviations (DMRA Max.) of 0.011 % and 0.439 %, respectively, indicating satisfactory fits to the experimental data. The excess volumes were calculated, revealing minimal deviation from ideal behavior, with a maximum deviation of 0.15 % of the total volume. This suggests that the volumetric behavior of the 1-butanol + methyl biodiesel system closely resembles that of an ideal solution. We used both equations to obtain derived properties, such as the compressibility (κ T) and the isobaric thermal expansivity (α P). It was observed that the PC-SAFT equation has some limitations in its prediction. From these results, a crossing point in isobaric thermal expansivity (α P) was observed; this could be attributed to increasing biodiesel content, potentially linked to the effects of intermolecular forces. [ABSTRACT FROM AUTHOR]

• Physico-chemical parameters are involved through the grand canonical ensemble. • The internal energy of the WPT-AC/ethanol and M-AC/ethanol systems are calculated. • The enthalpy and entropy functions of the adsorption cooling cycles are derived. • The COP is calculated by means of statistical physics treatment • Discussion of the obtained COP for different two cycles was showed. Thermodynamic analysis of two different adsorption cooling cycles was presented; the first cycle is based on an isobaric adsorption process and the second one projects an isothermal adsorption instead of an isobaric adsorption. These cooling cycles are carried out by employing the grand canonical ensemble of the statistical physics formalism. This investigation is done for two different adsorbate/adsorbent pairs i.e. Ethanol/Waste Palm Trunk (WPT-AC) and Ethanol/Mangrove wood (M-AC). The corresponding adsorption isotherms have been fitted by statistical physics models to give a description of the adsorption process through interpretations of the evolution of the involved physico-chemical parameters, specific for this process. The results showed that the ethanol molecules have been mainly adsorbed with a multimolecular process and non-parallel to the adsorbent surface involving an aggregation process before molecules adsorption. Their adsorption energies are varying from 1.40 to 3.64 kJ/mol for WPT-AC and from 3.2 to 3.81 kJ/mol for the M-AC. These values reflected a physisorption process. The calculated internal energy values suggested the exothermicity and the spontaneity of the ethanol adsorption process. The investigation aims providing a methodology of calculation of the COP for an adsorption cooling cycle by using the statistical physics treatment. The entropy and the enthalpy functions are calculated and used to perform the thermodynamic evaluation and to calculate the coefficient of performance (COP). This parameter was found to be in the interval [0.12–0.69] for ethanol/WPT-AC and [0.11-0.6] for ethanol/M-AC for the first cycle and for the second cycle [0.15-0.81] and [0.15-0.74] respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Presents a new semiempirical adsorbed phase activity coefficient model. • Proves thermodynamic consistency through model derivation and end-behavior analysis. • Model validated using over 25 systems after thoroughly testing data quality. • Binary and ternary adsorption predicted using Real Adsorbed Solution Theory. • Presents new binary adsorption data obtained using the Integral Mass Balance Method. The following study introduces a new adsorbed phase activity coefficient model, the SPLINT model, for describing nonideal multicomponent systems. The derivation is presented and simplification to the thermodynamically robust ABC model in the low‑coverage limit is shown. Both the SPLINT and ABC models are fit to 25 binary systems. Thermodynamic consistency of the data is established through multiple consistency tests including the intersection rule, closed‑loop reduced spreading pressure integration, the Gibbs‑Duhem integral equality, and alignment of pure and binary data. Regressed parameters are used in Real Adsorbed Solution Theory to predict both binary and ternary adsorption. The ABC and SPLINT models accurately describe systems with considerable nonideality when the activity coefficients are symmetric; however, the SPLINT model is required for accurate description of systems with complex, asymmetric activity coefficient behavior. The new model includes one more fitting parameter than the ABC model for a single binary system, but less across multiple data sets and higher‑order systems due to the theoretical basis. The importance of capturing activity coefficient asymmetry is demonstrated with a highly nonideal system across various pressures and temperatures measured by the present authors using the Integral Mass Balance method with HFC‑125 (pentafluoroethane), HFC‑32 (difluoromethane), and zeolite H‑ZSM‑5. The theoretical basis of the SPLINT model is further enforced by presenting two methods for predicting activity coefficients with the SPLINT model: correlating the fitting parameters individually and simultaneously regressing pure isosteric heat data to extract SPLINT fitting parameters. The study concludes with a discussion of pure and binary HFC‑125/HFC‑32 data with zeolite H‑ZSM‑5. A possible binary adsorption mechanism is proposed based on isosteric heat and excess enthalpy predictions and observed system irreversibility. [ABSTRACT FROM AUTHOR]

[Display omitted] • Feasible column sequences for pressure sensitive azeotropes explored. • Influence of pressure on azeotropic composition highlighted. • Effect of type of azeotropic mixture on derived column configurations deduced. • Effect of feed composition on column sequencing and process feasibility. The separation of azeotropic mixtures, particularly, pressure sensitive azeotropes is intriguing, challenging, and inevitable in chemical industries in comparison to pressure insensitive azeotropic mixtures. The main bottleneck for separating pressure sensitive azeotropes lies in the pressure selection and sequencing of distillation columns. A conundrum in pressure swing distillation for both minimum and maximum boiling azeotropes primarily about the feasibility of column configurations has been discussed in this work. The two column configurations, Low pressure Column-High Pressure Column (LPC-HPC) and High Pressure Column-Low Pressure Column (HPC-LPC) are found to be dependent on the feed composition, type of azeotrope (whether, minimum or maximum), and the effect of pressure on azeotropic composition. This article has explored concomitantly pressure swing distillation technique (continuous one) and the effect of various feed compositions on the column sequencing and process feasibility. A comprehensive strategy for both minimum and maximum boiling azeotropes has been proposed depending upon the effect of pressure on azeotropic composition. Two example case studies have been also presented in support of the proposed strategies for pressure swing distillation technique. [ABSTRACT FROM AUTHOR]

The purpose of the study is to simulate the process of isobaric evaporative crystallization of sucrose to substantiate new ways of its industrial implementation. Using computer simulation, a three-stage crystallization technology for semi-continuous boiling of massecuites on a prepared crystalline base of a seed suspension (first stage) and a crystalline base of the preceding massecuite (second and third stages) was designed. A computer computational model of the express method for determining the molasses saturation coefficient has been created. By heating to a temperature of 50–55 °C, the molasses is transferred to an unsaturated state, then oscillating white sugar crystals are partially dissolved until saturation is reached while under conductometric control. The method makes it possible to determine the optimal parameters of standard molasses, taking into account the technical characteristics of crystallization equipment and centrifuges. On the basis of simulation modeling in the VisSim software environment, tests were carried out, and a justification was given for the technology of semi-continuous boiling of massecuite massecuites to increase the efficiency of crystallization in batch vacuum pans. • Express method for determining the saturation coefficient and viscosity of standard molasses. • Optimizing models for assessing the solids content and purity of standard molasses. • Computer simulation of semi-continuous technology of boiling massecuite. • The advantages of boiling massecuites by moving the crystalline mass in three steps. • Comparison of the mode of boiling massecuites with different initial set of crystal mass. [ABSTRACT FROM AUTHOR]

• A total of 87 (p, rho, T) data of R1123 were measured from 300 K to 430 K and up to 6.9 MPa. • A new equation of state was developed for R1123 based on the present data. • The new equation calculates all thermodynamic properties with reasonable accuracies. • The new equation shows good extrapolation at very high and low temperatures and high pressures. The (p, ρ, T) behavior of trifluoroethene (R1123) was investigated with the isochoric method. A total of 87 (p, ρ, T) data were measured along nine isochores (42, 98, 151, 197, 296, 493, 691, 790, and 888 kg · m − 3) at temperatures from 300 K to 430 K and pressures up to 6.9 MPa. The uncertainties in temperature are estimated to be within 10 mK below 380 K and 20 mK at higher temperatures, and the uncertainties in pressure are estimated to be within 1 kPa below 380 K and 2 kPa at higher temperatures. The estimated relative uncertainties in the density measurements are 0.15 % or less. A new Helmholtz energy equation of state was formulated based on the (p, ρ, T) data and recently published experimental data for the vapor pressure, liquid and vapor densities including those at saturation, vapor-phase sound speed, and ideal-gas isobaric heat capacity. The equation is applicable at temperatures from the triple-point temperature (195.15 K) to 480 K and pressures up to 20 MPa. Typical uncertainties in calculated properties are 0.1 % for vapor pressures, 0.1 % for liquid densities, and 0.2 % for vapor densities, except in the critical region where larger deviations up to about 1.5 % are sometimes observed in densities. The uncertainties in calculated vapor-phase sound speeds and ideal-gas isobaric heat capacities are 0.03 % and 1 %, respectively. The equation shows reasonable extrapolation behavior at extremely low and high temperatures, and at high pressures. [ABSTRACT FROM AUTHOR]

The elimination of microbial cells is one of the most critical steps in food processing. Conventional heating is the application of diffusive and convective heat mechanisms and is traditionally applied to assure food safety. However, such process is also harmful to others thermosensitive compounds, compromising desirable sensorial characteristics. The large temperature gradients caused by conventional heating result in lower thermal efficiency, overheated zones and high processing times. To overcome these limitations, emergent technologies have been studied in the past years, such as ohmic heating. The aim of this review was to analyse the state of the art of microbial inactivation by ohmic heating. This study emphasizes comparisons of ohmic and conventional heating, as well as comparisons of ohmic heating in several distinct scenarios (such as variations in the frequency and electric field). The literature analysis shows that the most analysed microbial species was Escherichia coli and studies dealing with fungi were less numerous comparing with studies dealing with bacteria. Concerning the lethality of conventional and ohmic heating, authors have shown that ohmic treated foods had smaller D values in various temperatures. The effect of frequency lacks of experimental data to explain the real impact of this parameter in the inactivation rate, once different authors have found divergent results. Moreover, increases in the electric field and salt content and decreases in the pH, fat and solid content have demonstrated higher heating rates and, therefore, higher inactivation rates. • Recent data on microbial inactivation by ohmic heating were evaluated. • Parameters analysed were temperature, frequency, electric field and composition. • Ohmic heating can present nonthermal effects in a certain temperature range. • The frequency effects are still unclear due to the limited experimental data. [ABSTRACT FROM AUTHOR]

• Azeotropic region is defined by dipole moment and normal boiling point. • Positive azeotropes have better refrigeration capacity comparing to zeotropes. • It owes to the maximum pressure at the azeotropic location and the extreme density. • Series of positive azeotropic refrigerants are recommended at different application. Searching for the refrigerants with less influence on the global warming is one of the main challenges of the refrigeration industry. The azeotropic refrigerants are attracting increasing attentions due to their special thermophysical properties. An evaluation of mixed-refrigerants is performed on the vapor compression refrigeration cycle and regenerative cycle, synthetically considering the coefficient of performance (COP), volumetric refrigeration capacity (VRC), pressure ratio and discharge temperature. The tests show that all the positive azeotropic refrigerants achieved better VRC than its compositions. The COP of the mixtures is generally lower than that of the best individual refrigerants, but higher than the zeotropic compositions. The present results suggest the superiorities of the azeotropic refrigerants, especially for binary and ternary systems including ammonia. The maximum pressure at the azeotropic location and the consequent extreme density are the main reason why positive azeotropes dominate in refrigeration. [ABSTRACT FROM AUTHOR]

• We report a unified explicit formulation of Gibbs free energy for three compounds. • The proposed formulation involves experimental data of six molecular constants. • The developed formulation contains only one adjustable parameter. • We predict four thermodynamic properties of the considered three substances. • The predicted values are in excellent agreement with the NIST data. The explicit formulations of the Gibbs free energy subject to the concerned species are useful to determine the conditions for minimizing the total Gibbs free energy of a system with a simple way. Here, we develop a unified non-fitting explicit formulation of the Gibbs free energy for five compounds, including N 2 O, ClBO, OBBr, HBO and HCN. The established Gibbs free energy formulation is correlative only with masses of atoms and experimental data of six molecular constants of triatomic molecules, and away from requirement of fitting a plenty of experimental spectroscopic data or calorimetric data in conventional empirical expressions. For five compounds under consideration, the average absolute deviations between the predicted Gibbs free energy values and the data provided in the National Institute of Standards and Technology (NIST) database are within the range of 0.098% to 0.146%. Employing the developed unified non-fitting Gibbs free energy formulation with high accuracy, the theoretically predicted values of the entropy, enthalpy, and isobaric heat capacity for the concerned five substances are acquired, and the coresponding average absolute deviations from the NIST data are within the ranges of 0.166% to 0.263%, 0.571% to 2.533%, and 1.059% to 1.936%, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Raman spectra and X-ray diffraction patterns of MgP 2 O 6 were collected up to 1073 K. • No temperature-induced phase transition occurs for MgP 2 O 6. • The effect of temperature on the Raman active vibrations of MgP 2 O 6 was analyzed. • The thermal expansion coefficients and isobaric mode Grüneisen parameters of MgP 2 O 6 were determined. The Raman spectra and thermal expansion of MgP 2 O 6 metaphosphate were investigated at various temperatures up to 1073 K at ambient pressure. No temperature-induced phase transition was observed in this study. The effect of temperature on the Raman active vibrations and unit cell parameters was determined. All the observed Raman active bands of MgP 2 O 6 showed linear temperature dependences in the range of −2.61 × 10−2 ∼ −0.49 × 10−2 cm−1 K−1. The thermal expansion coefficient of MgP 2 O 6 was estimated to be 3.21(2) × 10−5 K−1. An axial anisotropic thermal expansion exists and the c -axis shows the smallest thermal expansion. The isobaric mode Grüneisen parameters of MgP 2 O 6 were calculated. The obtained results were compared with other compounds in the MgO-P 2 O 5 system. [ABSTRACT FROM AUTHOR]

This work investigated saturated vapor pressure and isothermal vapor-liquid equilibrium (VLE) for 1,1,1,2-Tetrafluoroethane (HFC-134a) + 3,3,3-trifluoropropene (HFO-1243zf) binary system. The saturated vapor pressures of HFC-134a and HFO-1243zf ranging from (273.17–353.13) K, and VLE data at four temperatures (283.15, 293.15, 313.15, 323.14) K for the HFC-134a + HFO-1243zf system were measured by a static-analytical apparatus. The vapor pressure data of HFO-1243zf were regressed by a Wagner type equation and compared with existing literature data. The experimental VLE data of HFC-134a + HFO-1243zf system were correlated by Peng-Robinson (PR) equation of state (EOS) combined with van der Waals (vdW) mixing rules. The binary interaction parameters were obtained, and correlation deviation was acceptable. Azeotropic behavior can be found for the HFC-134a + HFO-1243zf system at measured temperatures. Our work provides fundamental thermodynamic properties of new mixed refrigerants which are crucial to evaluate their cycle performance and optimize the design of refrigeration system. [ABSTRACT FROM AUTHOR]

n -Hexane is a significant component of industrial fluids. The speed of sound in supercritical n –hexane was measured by Brillouin light scattering (BLS) technique in the temperature range from (509.17–637.99) K along five isobars at p = (3.5, 4.5, 5.5, 6.5 and 7.5) MPa. The relative expanded measurement uncertainty in the speed of sound at the 95% confidence level is estimated to be 0.018. For the studied supercritical n –hexane, the change regularities of the speed of sound with increasing temperature and pressure are illustrated. Moreover, the well-known equation of state (EOS) proposed by Span and Wagner is assessed, and the absolute average deviation (AAD) between the experimental results and the calculated values is 0.89% for the whole examined p – T region. Image 1 ● New experimental data of the speed of sound in supercritical n -hexane along five isobaric lines were presented. ● An advanced optical method for measuring the speed of sound in supercritical fluid was reported. ● The EOS proposed by Span and Wagner was assessed by the experimental speed of sound in supercritical n -hexane. [ABSTRACT FROM AUTHOR]

Abstract In this work, the quantum-mechanical properties of the strongly non-linear quantum oscillator described by the Pöschl-Teller [PT] model is examined. This model has a relation with two well-known models, the free particle [FP] in a box and the harmonic oscillator [HO], as described in our previous works [1–3]. Using the [PT] model, a quantum-mechanical analogue of the Joule-Brayton [JB] cycle and Otto cycle have been constructed through changes of both, the width of the well and its the quantum state. The efficiency of quantum engines based on the Pöschl-Teller-like potential is derived, which is analogous to classical thermodynamic engines. Highlights • Efficiencies are analogous to classical thermodynamic engines i.e. Joule-Brayton and Otto cycles. • Equations are analogous to classical isobaric and isochoric processes in Joule-Brayton [J-B] and Otto cycles respectively. • Results when compare to earlier work of L.Guzmán-Vargas et al (2002) are the same when λ (L) = 1. • Results are intended largely for future statistical-mechanical and thermodynamic calculations. [ABSTRACT FROM AUTHOR]

Abstract Frozen storage of food comprises a large portion of global energy consumption, and in light of growing demand and increasing global temperatures, new solutions for increasing its energy efficiency are needed. Past efforts to improve refrigeration efficiency have focused primarily on improving the vapor-compression cycle and developing alternative heat pumps, but this study looks beyond the technology of cooling to the fundamental thermodynamics at play in the freezing of biological matter. Conventionally, food is frozen under isobaric conditions, e.g. at constant (atmospheric) pressure. Herein we use fundamental thermodynamic analyses to demonstrate that the process of freezing in an isochoric (constant volume) system requires up to 70% less energy compared to conventional freezing, and we develop novel phase change models to demonstrate newly discovered thermal effects that provide isochoric systems with exceptional temperature stability when exposed to ambient fluctuations (such as those encountered within freezers or during transportation), with the potential to substantially improve the energy efficiency of long-term storage and enhance preserved food quality. Our results show that a simple change in the thermodynamic state in which food is frozen and stored, from isobaric to isochoric, has the potential to substantially reduce the energy consumption of the global food storage industry, without the need to make major changes to existing refrigeration infrastructure. Highlights • Thermodynamic and heat transfer models are developed for isochoric freezing. • Isochoric containers can greatly increase the energy efficiency of food cold storage. • Unique thermodynamics link sensible and latent heat effects in isochoric systems. • Temperature fluctuations can be reduced 10x in isochoric systems. • Food matter can become an effective phase change material in isochoric freezing. [ABSTRACT FROM AUTHOR]

Abstract In this work a new method for inclusion of pressure effects in COSMO-type activity coefficient models is proposed. The extension consists in the direct combination of COSMO-SAC and lattice-fluid ideas by the inclusion of free volume in form of holes. The effort when computing pressure (given temperature, volume, and mole numbers) with the proposed model is similar to the cost for computing activity coefficients with any COSMO-type implementation. For given pressure, computational cost increases since an iterative method is needed. This concept was tested for representative substances and mixtures, ranging from light gases to molecules with up to 10 carbons. The proposed model was able to correlate experimental data of saturation pressure and saturated liquid volume of pure substances with deviations of 1.16% and 1.59%, respectively. In mixture vapor-liquid equilibria predictions, the resulting model was superior to Soave-Redlich-Kwong with Mathias-Copeman α -function and the classic van der Waals mixing rule in almost all cases tested and similar to PSRK method, from low pressures to over 100 bar. Good predictions of liquid-liquid equilibrium were also observed, performing similarly to UNIFAC-LLE, with improved responses at high temperatures and pressures. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract Leakage in isobaric energy recovery devices (ERDs) is inevitable. Three seal structures are introduced and studied for a fully-rotary valve energy recovery device (FRV-ERD) to reduce leakage. Effects of pressure difference and geometrical parameters of seal structure on leakage are investigated and compared for different seal structures. Results show that, as the key component of this ERD, the fully-rotary valve (FRV) achieves its best seal performance with the bilateral seal. For the FRV-ERD of design parameters, both the efficiency and required clearance are improved by using the bilateral seal to replace the original seal. The calculated efficiency is improved from 89.48% to 92.05% at the clearance of 30 μm under operating pressure and the required clearance increases from 18.1 μm to 20.4 μm. Based on the results of the optimized bilateral seal, an approximate leakage rate equation is proposed and can be used for design calculation. The performance of FRV-ERD with the optimized bilateral seal is improved greatly. Compared with FRV-ERD with the original seal, the efficiency of FRV-ERD with the optimized bilateral seal is improved from 89.48% to 96.33% at the clearance of 30 μm under operating pressure, and the required clearance increases from 18.1 μm to 29.5 μm, easing machining difficulty greatly. Highlights • Three different seal structures are firstly introduced for a new isobaric ERD and their leakage are studied systematically. • Performance of the ERD with different seal structures are studied and compared. • An approximate leakage rate equation is obtained for the optimized seal structure. [ABSTRACT FROM AUTHOR]

Highlights • A multiscale micromechanical homogenization framework is proposed for fluid-filled porous materials. • The overall elastic properties of the fluid-filled porous materials are determined in the framework. • The effects of pore distribution and fluid pressure on the effective elastic properties are quantified. • By considering the fluid diffusion from macro- to micro-scale pores, evolution of the effective properties is predicted. Abstract Fluid-filled porous materials are widely encountered in natural and artificial systems. A comprehensive understanding of the elastic behavior of such materials and its dependence on fluid diffusion is therefore of fundamental importance. In this work, a multiscale framework is developed to model the overall elastic response of fluid-filled porous materials. By utilizing a two-dimensional micromechanical model with porosity at two scales, the effects of fluid diffusion and the geometric arrangement of pores on the evolution of effective properties in fluid-filled porous materials are investigated. Initially, for a single-porosity model the effective elastic properties of the dry and fluid-filled porous materials with ordered pores are obtained theoretically by considering a geometrical factor, which is related to the distribution of pores in the matrix. Model predictions are validated by finite element simulations. By employing a double-porosity model, fluid diffusion from macro- to micro-scale pores driven by a pressure gradient is investigated, and the resulting time-dependent effective elastic properties are obtained for both constant pressure and constant injection rate conditions. It is found that the presence and diffusion of pressurized pore fluid significantly affect the elastic response of porous materials, and this must be considered when modeling such materials. It is expected that the proposed theoretical model will advance the understanding of the fluid-governed elastic response of porous materials with implications towards the analysis of geophysical, biological and artificial fluid-filled porous systems. Graphic abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

Abstract Thousands of polymers have been synthesized to produce membranes for gas permeation. Currently, their potential as a viable material is often bench-marked in the so-called Robeson plot. This plot gives a first impression of the transport properties at ideal low pressure conditions and ambient temperature. However, these data are of limited significance as they do not represent realistic process conditions. Here, we present a new methodology which allows a more comprehensive judgment of membrane transport properties based on their influence on overall processing costs. In particular, we apply this methodology to the question whether the materials discovered so far offer benefits when applied at sub-ambient temperatures. For a variety of applications, this rigorous approach proves that for certain materials the overall process costs can be minimized by applying sub-ambient process conditions. It also emphasizes that temperature-dependent permeation data is important to be reported for new materials. Graphical abstract fx1 Highlights • Adding temperature dependency to the Robeson-plot. • Extending the window of considerable operation conditions for membrane processes. • Data analysis of temperature dependence of gas permeability in polymers. • Economic evaluation of low temperature gas permeation processes. • Process optimization to find optimal operation temperature. [ABSTRACT FROM AUTHOR]

Abstract In this work, we have studied selected rheological properties and mechanical properties of rock-based geopolymers. The geopolymers are suggested for zonal isolation and permanent abandonment of hydrocarbon wells. Our viscosity measurements of the geopolymeric slurries shows a very small yield stress and a nearly constant additional viscosity. To find the effect of mechanical vibration, a rotational viscometer was modified by being equipped with a mechanical vibrator. Consistency of the geopolymeric slurry was measured by utilization of atmospheric and pressurized consistometers to find the impact of pressure and temperature on pumpability. The downhole temperature uncertainty was also studied by using atmospheric consistometers. Static-fluid-loss is an issue, which causes loss of hydrostatic pressure. Therefore, static-fluid-loss test was carried out. Strength development of the geopolymeric slurry was measured directly and indirectly by utilization of uniaxial compressive strength and Ultrasonic Cement Analyzers, respectively. As the pre-defined algorithm could not convert the sonic velocity to sonic strength, a custom algorithm was generated. The elastic shear wave and compressional wave velocities and velocity anisotropies of the samples were tried to be determined experimentally. The measurements were conducted on cube-shaped specimens in a triaxial multi-anvil press using the ultrasonic pulse-transmission technique. As it is necessary to study the bond strength between the geopolymers and pipe, steel pipe was used. The shear bond strength between pipe and the rock-based geopolymer was measured. Highlights • Rock-based geopolymers have the potential to be used as zonal isolation material. • The geopolymers show non-Newtonian fluid behavior. • The geopolymeric slurry has low fluid loss in static conditions. • Geopolymerization is strong function of temperature. • Particle segregation of the geopolymeric precursors does not occur. [ABSTRACT FROM AUTHOR]

Abstract The use of compositional reservoir simulation is necessary to better represent the physical phenomena associated with enhanced oil recovery methods, particularly with miscible or near-miscible gas injection processes. However, upscaling of the geological fine model is required because computational costs can make it unpractical to perform compositional simulations in fine-scale models. Therefore, upscaling of fine-scale geological models is important and the use of coarse-scale models in reservoir simulation is necessary to reduce computational time. However, it can degenerate results due to loss of resolution of the small-scale phenomena, averaging of sub-grid heterogeneity and numerical dispersion, especially in oil fields where miscible gas is injected, continuously or alternatively with water (WAG). In black oil simulations, errors of the upscaling process are usually mitigated with the use of pseudo relative permeability curves when two-phase immiscible displacement is considered. In compositional reservoir simulation of miscible gas injection, the interaction between thermodynamic phase behavior and the sub-grid heterogeneities significantly increase the challenge of the upscaling procedures. This work presents a new technique for a robust upscaling of compositional displacements allowing a better representation of the small-scale results when miscible gas injection is considered, as in cases in which the produced gas is partially or totally reinjected in the reservoir. It can be applied in any compositional simulator with no need to adapt any transport coefficient or to use dual porosity dual permeability models, thus providing a flexible and computationally efficient approach. The proposed technique is based on employing an alternative fluid model with a pseudo minimum miscibility pressure (PMMP) above experimental values, in order to ensure an immiscible displacement. This solution does not violate the phase behavior and ensures formation of two hydrocarbon phases in the reservoir. Therefore, the gas relative permeability plays a role on the simulation results and can be used for an improved fit of the fine model production curves. The technique is applied in two steps, first an alternative fluid model is generated and then pseudo relative permeability curves are used to better fit the production curves. In this study, problems that occur when upscaling is applied in fields with miscible gas injection were investigated. We show that the proposed technique can significantly improve the coarse-scale results – production curves, sweep efficiency and gas saturation map profile - in different scenarios of heterogeneity. Three case studies were evaluated and compared with the standard static upscaling processes. Additionally, we show improvements in the production curve results and physical representation of gas injection behavior. [ABSTRACT FROM AUTHOR]

Highlights • The linear stability analysis of a fluid saturated inclined porous layer is presented. • The layer has a lower impermeable and an upper permeable boundary. • The layer boundaries are isothermal at different temperatures. • The longitudinal rolls turned out to be the most unstable modes. Abstract The linear stability analysis of a fluid saturated porous layer is carried out. The porous layer is inclined to the horizontal and is infinitely wide. One boundary of the layer is permeable while the other one is impermeable. The two boundaries are subject to different temperatures, so that convective instability may arise when such a temperature difference exceeds a threshold value. The basic state whose stability is studied consists of a single cell with no net mass flow rate. The critical values of the governing parameters are computed numerically and are presented as functions of the inclination angle. The threshold relative to the horizontal layer recovers the results already present in the literature. The inclination angle comes out to be a stabilising parameter such that the vertical layer cannot become unstable. [ABSTRACT FROM AUTHOR]

• Distinctly different mixing behaviors from different schemes are analyzed. • Two limiting mixing models are identified. • Theoretical analysis is confirmed with numerical simulation results. • Available experimental data is utilized to assess different mixing models. Accurate and robust simulations of transcritical real-fluid flows are crucial for many engineering applications. Diffuse-interface methods are frequently employed and several numerical schemes have been developed for simulating transcritical flows. These schemes can be categorized into two types, namely fully conservative (FC) and quasi-conservative (QC) schemes. In this study, numerical analysis is conducted to show that the mixing processes for isobaric systems follow the limiting cases of adiabatic and isochoric mixing models when FC and QC schemes are employed, respectively. It is shown that these distinct mixing behaviors are a consequence of numerical diffusion instead of physical diffusion, and can be attributed to insufficient spatial resolution. By considering several test cases, numerical simulations confirm these theoretical results. The analysis of experimental data suggests that the isochoric mixing provides better agreement in terms of the phase separation behavior. This analysis provides quantitative understanding on the interpretation of numerical simulation results and the mixing models that are commonly used to study transcritical flows. [ABSTRACT FROM AUTHOR]

Abstract Simultaneous effect of pressure, temperature and plastic strain on structural evolution of titania ceramic nanopowder was investigated using the high-pressure torsion (HPT) method. Unlike static annealing, in which the anatase-to-rutile phase transformation occurred at 1173 K, the transformation was observed at low temperatures as 473–573 K by HPT processing. The formation of rutile phase accompanied with dynamic recrystallization and an unusual grain growth, indicating that severe plastic deformation at low homologous temperatures does not necessarily result in grain refinement of metastable nanoceramics. Besides the coarsened grains of rutile phase, a high-pressure TiO 2 -II columbite phase was also detected in small nanograins. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract The RM-wrap (RM = Refractory Metal) is a pressure-less, versatile and tailorable joining process: it consists of wrapping Si foils inside a refractory metal wrap (i.e., Mo, Nb, Ta) in order to prevent molten silicon from leaking outside the joined region and infiltrating the facing materials during the joining process. RM-wrap (RM = Mo, Nb, Ta) has been successfully applied to join C/SiC composites in this work: optimized joining treatment consisted of heating to 1450 °C with a heating rate of 1000 °C/h followed by a dwell time of 5 min in a non-reactive environment of Argon flow. The joints were characterized by morphological analysis and lap shear tests at room temperature and 1000 °C. Microscopical analysis revealed an in-situ formed composite joint consisting of a silicon matrix reinforced with silicides of the refractory metals. Joining material exhibited continuous and cracked free bonding with C/SiC irrespective of composite fibre orientation. Joints lap shear strength values at 1000 °C were higher than at room temperature, probably due to the brittle to ductile transition (BTDT) of silicon and silicides. Vickers microhardness on refractory metal disilicides measured inside the joints showed a trend similar to their mechanical strength, with higher lap shear strength and hardness for Mo-Wrap and lower for Ta-wrap joints. [ABSTRACT FROM AUTHOR]

Highlights • CO 2 huff 'n' puff process study on CO 2 storage and enhance heavy oil recovery. • A novel equation to predict relation between CO 2 and heavy oil production. • A new terminology is defined to analyze the production performance. • The soaking time and pressure depletion rate are optimized and upscaled. Abstract In order to study a potential way to store CO 2 and enhance heavy oil production performance, five experiments are implemented on the CO 2 huff 'n' puff process using long cores. The production profiles of the CO 2 huff 'n' puff process are analyzed, including pressure, heavy oil recovery factor, gas production, cumulative gas oil ratio, and pressure difference. The pressure drops indicate the CO 2 diffusion in heavy oil. The pressure drop in the first cycle is much lower than those in the subsequent cycles. The heavy oil recovery factor is higher than 32.75% and can reach as high as 38.02% under the pressure depletion rate of 1 kPa/min. A main trend observed for each test is that the heavy oil recovery factor decreases with increases in the cycle number. With oil production, a growing space is available for CO 2 injection in the core, resulting in a higher volume of injected CO 2 together with increasing gas production and a cumulative gas oil ratio. With less heavy oil production, the pressure difference between the end port and the production port decreases with the cycle number increases. A novel equation is developed to study the relationship between CO 2 production and heavy oil production, and the agreement between the equation and the experimental data is extremely high ( R 2 > 0.97). This novel equation can be applied to predict the production performance in the later production period in the same cycle and/or to predict the performance in the subsequent cycles. Via the analyzation of the production performance of the CO 2 huff 'n' puff process in heavy oil under different pressure depletion rates and different soaking times, the effect parameters, including pressure depletion rates, soaking time and cycle numbers, are optimized in this study. The optimized pressure depletion rates, soaking time, and cycle numbers are 1 kPa/min, 5 h and 3 cycles, respectively. The optimized parameters gained in the tests were upscaled using the scaling criteria, and the upscaled parameters can be applied in the field pilot test to enhance heavy oil recovery using the CO 2 huff 'n' puff process. [ABSTRACT FROM AUTHOR]

Abstract Enzymatic 18O exchange, the well-established approach in comparative proteomics, has some disadvantages such as back exchange of labeled oxygen and overlapping the peak of a labeled peptide with isotopic peaks of an unlabeled one. Herein we demonstrated a simple procedure in which samples digested with a trypsin (with and without H 2 18O) were reacted with unlabeled and quadrupled 13C-labeled pyrylium salt respectively which results in formation of pyridinium cations. Thus, each isobarically labeled peptide containing zero or four 13C atoms in the mass reporter group, during tandem MS/MS forms an unique reporter ion useful for a relative quantitation. Such a sample treatment improves the signal to noise ratio, reduces overlapping of the isotopic peaks and completely eliminates the back exchange problem. Graphical abstract Image 1 Highlights • Formation of the isobaric peptides derivatives (duplex) in two samples compared. • A combination of enzymatic incorporation of 18O and reaction with 13C pyrylium salt. • The MS/MS experiment generates diagnostic ions shifted by 4 Da. • It solves the problem of overlapping of the isotopic peaks in the 18O approach. • Method eliminates the risk of back-exchange and increase of the ionization efficiency. [ABSTRACT FROM AUTHOR]

Abstract In these proceedings we show that the premise of the isobaric Ru 44 96 + 44 96 Ru and Zr 40 96 + 40 96 Zr collisions to search for the chiral magnetic effect (CME) may not hold as originally anticipated due to large uncertainties in the isobaric nuclear structures. We demonstrate this using Woods-Saxon densities and the proton and neutron densities calculated by the density functional theory. Furthermore, a novel method is proposed to gauge background and possible CME contributions in the same system, intrinsically better than the isobaric collisions of two different systems. We illustrate the method with Monte Carlo Glauber and AMPT (A Multi-Phase Transport) simulations. [ABSTRACT FROM AUTHOR]

Abstract The isobaric collision experiment at RHIC provides the unique opportunity to detect the possible signal of Chiral Magnetic Effect (CME) in heavy ion collisions. The idea is to contrast the correlation observables of the two colliding systems that supposedly have identical flow-driven background contributions while quite different CME signal contributions due to the 10% variation in their nuclear charge and thus magnetic field strength. With the recently developed quantitative simulation tool for computing CME signal, the Anomalous-Viscous Fluid Dynamics (AVFD), we demonstrate that a joint (multiplicity + elliptic-flow) event selection is crucial for this purpose. We further propose to use the absolute difference between RuRu and ZrZr events (after using identical event selection) for detecting CME signal and make predictions for the correlation observables. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Pressure where CO 2 permeability reaches maximum is temperature dependent. • Feed density and not intrinsic membrane property dictate CO 2 permeability profile. • Trend of CO 2 fluid density and concentration in PDMS are alike, at high pressures. • Phase change from gaseous- to liquid-like CO 2 leads to altered permeation behavior. • Transition to liquid-like state leads to lowered CO 2 diffusion within the polymer. Abstract Supercritical carbon dioxide (scCO 2) is used in the food industry as a water-extracting drying agent. Once saturated with water, the scCO 2 needs to be regenerated. A promising way of drying scCO 2 is by using H 2 O permeable membranes. Ideally, these membranes demonstrate low CO 2 permeability. Here, we investigated the CO 2 permeability of three types of dense membranes, Nafion, Natural Rubber and PDMS, of which the latter in more detail because of its ease of handling. The experimental conditions, temperature and pressure, resulting in minimum CO 2 permeability (=losses) were explored. Even though the absolute CO 2 permeability depends on the intrinsic membrane material properties, its trend with increasing feed pressure is defined by the (supercritical) behavior of CO 2 , notably its density as a function of temperature and pressure. The data points to transitions within the supercritical regime, from the gaseous-like supercritical state to the liquid-like supercritical state, graphically visualized by the Widom line for CO 2 density. Sorption measurements with PDMS membranes confirm this behavior that follows the diffusion-solution theory. In the gaseous state, the (normalized) permeability follows the (normalized) solubility, indicating a constant CO 2 diffusivity. With increasing pressure and when entering the liquid-like (supercritical) regime, the diffusivity drops, resulting in a (normalized) permeability that starts to lag behind the (normalized) solubility. [ABSTRACT FROM AUTHOR]

Abstract Vacuum distillation is selected as a technique for recycling in order to separate the mixture of a hydrometallurgical organophosphoric extractant from an organic diluent because of their low volatility and high selectivity. The experimental isobaric vapor-liquid equilibrium (VLE) data for the binary systems of di-(2-ethylhexyl) phosphoric acid (D2EHPA) + n-dodecane and tri-butyl phosphate (TBP) + n-dodecane were measured at pressures of 0.13, 2.40 and 6.67 kPa, using a glass vapor-liquid equilibrium ebulliometer. VLE data were generated in the form of T − x − y diagrams and checked for thermodynamic consistency via Herington area test and Van Ness point test. Data for all mixtures met the criteria of thermodynamic consistency and were found suitable for process modeling. At each pressure point, no azeotropic phenomenon was observed. Reduction in pressure of the system can significantly enhance the relative volatility and separation efficiency of both mixtures. At all pressure points, D2EHPA was noted to be more separable than TBP. Additionally, the experimental VLE results for all systems were found to have a good correlation with Raoult's law, Wilson and nonrandom two-liquid (NRTL) models. The corresponding binary interaction parameters were obtained by minimizing the deviation between the experimental and the calculated vapor phase composition and total pressure. Graphical abstract Image 1 Highlights • VLE of D2EHPA/TBP + n-dodecane are reported at p = 0.13, 2.40 and 6.67 kPa. • No azeotropic phenomenon are observed over studied pressure range. • VLE data pass the consistency test by Herington area test and Van Ness point test. • Good correlation with Raoult's law, NRTL and Wilson model are confirmed by | Δ y i | < 0.01. • D2EHA + n-dodecane systems are more ideal than TBP + n-dodecane. [ABSTRACT FROM AUTHOR]

Graphical abstract Image 1 Highlights • Automated sample preparation method for Sr and Pb isotopic analysis • Simultaneous, quantitative separation of Sr and Pb in Ca-rich matrices • Investigation of the effects of residual Ca on Sr isotope ratio analysis using CRMs • Sr and Pb isotope ratio data for different Ca-rich reference materials • First n (87Sr)/ n (86Sr) value for reference material BCR-063R presented in literature. [ABSTRACT FROM AUTHOR]

Abstract The long-lived radionuclide 93Zr t 1/2 = (1.61 ± 0.05) Ma plays an important role in nuclear astrophysics and nuclear technology. In stellar environments, it is mainly produced by neutron capture on the stable nuclide 92Zr. On Earth high amounts of radioactive 93Zr are produced in nuclear power plants directly from 235U fission, but also by neutron capture on 92Zr, as Zr-alloys are commonly used as cladding for nuclear fuel rods. Despite its importance, the neutron capture cross section of 92Zr at thermal and stellar energies (keV) is not well known. Neutron irradiation of 92Zr and subsequent determination of produced 93Zr via AMS is a promising approach to resolve this issue. The main challenge in AMS measurements of 93Zr is the interference from the stable isobar 93Nb. The high particle energies available with the 14UD tandem accelerator at the Australian National University are ideal to tackle this challenge. Different sample materials, molecular ion species and sample holder materials were tested for their 93Nb background. Commercial ZrO 2 powder irradiated with thermal neutrons from the reactor at the Atominstitut in Vienna (ATI) was used as reference material for AMS measurements. In contrast to literature reports and γ-activity measurements of 95Nb, which suggest that chemical Nb reduction works, elevated 93Nb contents were measured in chemically pre-treated samples. The reasons are under investigation. At the ANU we developed AMS for ∼210 MeV 93Zr ions using an 8 anode ionisation chamber. We achieved background levels of 93A/Zr ∼ 10−12 with acceptance of 2–8% of the 93Zr ions at the high-energy side. This is more than an order of magnitude better than previously reported. The 93Nb isobar was suppressed by a factor between 13,000 and 90,000 in the detector. This performance allows measurements of the thermal and stellar neutron-capture cross section of 92Zr for samples irradiated at the ATI and the Soreq Applied Research Accelerator Facility, respectively, using AMS. [ABSTRACT FROM AUTHOR]

[Display omitted] • We report a unified explicit formulation for the Gibbs free energy of the gas NO 2 , gaseous BF 2 and AlCl 2 radicals. • The developed formulation with an adjustable parameter depends only on experimental data of six molecular constants. • The predicted values of four thermodynamic properties for three substances are in excellent agreement with the NIST data. We present a unified explicit formulation for the Gibbs free energy of the gas NO 2 , gaseous BF 2 and AlCl 2 radicals. It depends only on experimental data of atomic masses and six molecular constants except for an adjustable dimensionless pure number. In the temperature range from 298 to 6000 K, the average absolute deviations of the predicted Gibbs free energy values with the developed formulation from the NIST data are within 0.021 % and 0.069 % for the considered substances. The predicted values for the entropy, enthalpy and isobaric heat capacity are also consistent with the NIST data. [ABSTRACT FROM AUTHOR]

• Dynamics and control of a modified PSD-FHI characterized by high reflux ratios. • Separating a maximum-boiling azeotrope featured small pressure-induced shift. • Controlling HPC pressure with an auxiliary condenser avoids safety issues. • Novel control structures are developed to handle huge perturbations effectively. Pressure-swing distillation (PSD) is an alternative configuration used to separate pressure-sensitive azeotropes and avoid product contamination(s) in extractive or heterogeneous azeotropic distillation via the entrainer(s). Full heat integration between high- and low-pressure columns (HPC and LPC) can provide significant energy savings compared to the conventional case, while it also loses the control degree of freedom, trim condenser or reboiler heat load, via the integrated condenser/reboiler exchanger. Typically, the pressure of HPC is left uncontrolled, and additional pressure-compensated control strategies are implemented, which may create safety issues. To address this, the study proposes adding an auxiliary cooling-water-driven condenser to the fully heat-integrated PSD system, providing an extra manipulated variable to regulate the pressure of HPC. Compared to the conventional PSD system, the new modified process could achieve a 26.31% reduction in total annual cost. The research uses the maximum-boiling azeotropic mixture of acetone/chloroform as a case study which makes the distillation system characterized by high reflux ratios and a large recycle flow rate, leading to the unwelcome snowball effect. To achieve effective process control, robust control structures are proposed that rigorously regulate the pressure of the column by manipulating the heat removal in the trim condenser, attenuating or eliminating potential overpressure issues. Product purity and other evaluation indicators, such as product transient deviations, offsets, integral absolute error, and oscillation degrees, are also considered. Results show that the proposed control schemes can efficiently control the pressure of HPC, weaken the snowball effect, and maintain product purity. This study highlights the importance of pressure control for fully heat-integrated PSD systems, particularly for pressure-sensitive azeotropes with small pressure-induced shifts. [ABSTRACT FROM AUTHOR]

Abstract Background Spinal cord injury (SCI) is a disease associated with high disability and mortality rates. The transitional phase from subacute phase to intermediate phase may play a major role in the process of secondary injury. Changes in protein expression levels have been shown to play key roles in many central nervous system (CNS) diseases. Nevertheless, the roles of proteins in the transitional phase of SCI are not clear. Methods We examined protein expression in a rat model 2 weeks after SCI and identified differentially expressed proteins (DEPs) using isobaric tagging for relative and absolute protein quantification (iTRAQ). Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of DEPs were performed. Furthermore, we constructed a protein-protein interaction (PPI) network, and the top 10 high-degree core nodes were identified. Meanwhile, we validated protein level changes of five high-degree core regulated proteins using Western blots. Results A total of 162 DEPs were identified between the injury group and the control, of which 101 (62.35%) were up-regulated and 61 (37.65%) were down-regulated in the transitional phase of SCI. Key molecular function, cellular components, biological process terms and pathways were identified and may be important mechanisms in the transitional phase of SCI. Alb , Calm1 , Vim , Apoe , Syp , P4hb , Cd68 , Eef1a2 , Rab3a and Lgals3 were the top 10 high-degree core nodes. Western blot analysis performed on five of these proteins showed the same trend as iTRAQ results. Conclusion The current study may provide novel insights into how proteins regulate the pathogenesis of the transitional phase after SCI. Highlights • iTRAQ was applied to identify DEPs in transitional phase of SCI for the first time. • We constructed a proteomic database of transitional phase of SCI for the first time. • Crucial proteins that may contribute to the pathogenesis of SCI in the transitional phase were identified. [ABSTRACT FROM AUTHOR]

Highlights • Adsorption of proteins to both lignin and pseudo-lignin was investigated. • Analyses included quantitative proteomics based on isobaric mass tagging. • Adsorption to spruce lignin was more extensive than adsorption to hardwood lignins. • Results suggest that carbohydrate-binding modules affect the adsorption pattern. Abstract Catalytically non-productive adsorption of fungal enzymes to pseudo-lignin (PL) was compared to adsorption to lignin preparations derived from different sources (SL, spruce; BL, birch; OL, beech) using different methods [steam pretreatment/enzymatic saccharification (SL, BL) and organosolv processing (OL)]. The protein adsorption to the SL was more extensive than the adsorption to the hardwood lignins, which was relatively similar to the adsorption to the PL. The adsorption patterns of 13 individual proteins were studied using isobaric mass tagging with TMTsixplex reagent and LC–MS/MS analysis. The results suggest that, on an average, adsorption of proteins equipped with carbohydrate-binding modules, such as the cellulases CBHI, EGII, and EGIV, was less dependent on the quality of the lignin/PL than adsorption of other proteins, such as β-Xyl, Xyn-1, and Xyn-2, which are involved in xylan degradation. [ABSTRACT FROM AUTHOR]

Highlights • A new, simple universal correlation that predicts the onset of nucleation temperature following a rapid isobaric heating process, is developed. • The correlation predicts the nucleation temperature, as a function of the heating rate, based on the saturation temperature and on the homogeneous nucleation temperature. • The predictions are validated for different types of liquid: water, methanol, ethanol (polar) and heptane and toluene (non-polar) at one atm. [ABSTRACT FROM AUTHOR]

Three imidazolium-based ionic liquids: 1-methy-3-methylimidazolium dimethylphosphate ([MMIM][DMP]), 1-ethyl-3-methylimidazolium diethylphosphate ([EMIM][DEP]) and 1-butyl-3-methylimidazolium dibutylphosphate ([BMIM][DBP]) were used as entrainers to separate acetonitrile + ethanol mixtures. Isobaric vapor-liquid equilibrium (VLE) data were measured at 101.3 kPa. Addition of ionic liquids (ILs) produced a crossover effect on the VLE of the acetonitrile + ethanol system and the azeotropic phenomenon of acetonitrile and ethanol could be eliminated as the mole fraction of ionic liquids reaches a certain value. The separation performance of the three ILs follows the order of [BMIM][DBP] > [EMIM][DEP] > [MMIM][DMP]. Finally, the experimental VLE data were well fitted with the nonrandom two-liquid (NRTL) model. [ABSTRACT FROM AUTHOR]

The ionic liquids 1-methyl-3-octylimidazoliumbis (trifluoromethylsulfonyl)imide ([OMIM][Tf 2 N]) and 1,2-dimethyl-3-octylimidazolium bis(trifluoromethylsulfonyl)imide ([OMMIM][Tf 2 N]) were utilized as extractive distillation entrainers to make methanol as the volatile component for the separation of the azeotropic mixture of methanol and methyl acetate. Isobaric VLE data for the methanol (1) + methyl acetate (2) + [OMIM][Tf 2 N] and methanol (1) + methyl acetate (2) + [OMMIM][Tf 2 N] were measured at 101.3 kPa. The experimental data were correlated by NRTL model and UNIFAC model, and the NRTL model is more accurate. Both [OMIM][Tf 2 N] and [OMMIM][Tf 2 N] produce notable salting-out effects and make methanol as the volatile component, and the azeotropic point of methanol + methyl acetate can be eliminated if the mole fraction of [OMMIM][Tf 2 N] or [OMIM][Tf 2 N] is greater than 0.4. The mechanism of [OMMIM][Tf 2 N] and [OMIM][Tf 2 N] to improve the relative volatility of methanol to methyl acetate were investigated, and the salting-out effects of [OMMIM][Tf 2 N] is a little larger. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • New operational mode of ion preparation trap used for multi-reflection time-of-flight mass spectrograph. • Improved method for determination of ion mass for spectral peaks outside the nominal mass bandwidth of a multi-reflection time-of-flight mass spectrograph. • Accurate relative precision of 10−7 can be obtained even without isobaric reference ion. Abstract We introduce a new concomitant referencing mode for operating a multi-reflection time-of-flight mass spectrograph (MRTOF-MS), wherein the reference and analyte ions are interleaved on a cycle by cycle basis. Using this mode, we demonstrate an improved technique for performing wide bandwidth mass measurements via MRTOF-MS. This new technique offers a simplified analysis and high accuracy. [ABSTRACT FROM AUTHOR]

Isobaric vapor-liquid equilibrium data have been measured for the ternary system ethanol + hexane + 2,5 – dimethylfuran at 94 kPa and in the temperature range 330–344 K. Equilibrium determinations were performed in a vapor-liquid equilibrium still with circulation of both phases. The dependence of interfacial tensions of the ternary mixture on concentration was also experimentally determined at atmospheric pressure and 298.15 K, using the maximum differential bubble pressure technique. From the experimental results, it follows that the ternary mixture exhibits positive deviation from ideal behavior. Furthermore, the determined interfacial tensions exhibit negative deviations from the linear behavior, and ternary aneotropy is observed. The vapor-liquid equilibrium (VLE) data of the ternary mixture past the consistency test and were well correlated by Redlich–Kister expansion and predicted by the nonrandom two-liquid (NRTL), Wilson and universal quasichemical (UNIQUAC) activity coefficient models using binary parameters only. The interfacial tensions (IFT) were smoothed using the Myers-Scott expansion, showing an important contribution of parameters that describe three-body interactions, thus suggesting that the ternary interfacial tensions data cannot be initially predicted from the binary contributions. The experimental isobaric VLE and isothermal IFT data of the ternary mixture were accurately characterized by applying the linear square gradient theory to the Peng–Robinson Stryjek–Vera equation of state (EoS) appropriately extended to mixtures by means of the modified Huron–Vidal mixing rule. This model allows directly transferring the experimental excess Gibbs energy function to the EoS model for equilibrium and interfacial tension calculation purposes. This theoretical framework shows that both experimental VLE and IFT data can be accurately predicted by using binary contributions and provide a route to interpolate values phase equilibrium and interfacial tension. [ABSTRACT FROM AUTHOR]

Isobaric vapor - liquid equilibrium (VLE) data for the binary system of ethanol + dimethyl carbonate (DMC) and the ternary systems of ethanol + DMC + 1-hexyl-3-methylimidazolium bis[(trifluoromethyl) sulfonyl] imide ([HMIM][NTf 2 ]) and ethanol + DMC + 1-butyl-3-methylimidazolium bis[(trifluoromethyl) sulfonyl] imide ([BMIM][NTf 2 ]) were obtained by using a modified Othmer still at a constant pressure of 101.3 kPa. The experimental results indicated that both [HMIM][NTf 2 ] and [BMIM][NTf 2 ] had a notable effect on the azeotropic system of ethanol - DMC. The NRTL model was used in this work to correlate VLE data and the calculated data agreed well with the experimental value. The minimum mole fractions of [HMIM][NTf2] and [BMIM][NTf2] needed to eliminate azeotrope were 0.125 and 0.170 calculated by NRTL model, respectively. And the [HMIM][NTf2] was found to be a better candidate of entrainer for separating the ethanol - DMC azeotrope. [ABSTRACT FROM AUTHOR]

This study presents a method for high-precision stable potassium (K) isotope analysis using High-Resolution Multi-Collector Inductively Coupled Plasma Mass Spectrometry (HR-MC-ICPMS). Dry and cold plasma is used to suppress the formation of argon hydrides that are direct isobaric interferences on K isotopes. The residual 40 Ar 1 H + beam is resolved from 41 K + by using pseudo-high resolution mode, providing interference-free shoulders of 39 K + and 41 K + for isotopic measurements. Precision of better than 0.06‰ (95% confidence interval) has been routinely achieved based on multiple measurements of pure K standard solutions and rock standards over a six-month period. Mismatches in K concentration (up to 20%) and acid molarity (up to 67%) between samples and bracketing standards, as well as the presence of substantial amount of matrix element Rb, do not significantly affect the analytical precision and accuracy. Our study documents that high-precision K isotope analysis can be routinely achieved for a wide variety of natural samples by HR-MC-ICPMS, which makes it possible for using K isotopes to trace major geological processes. [ABSTRACT FROM AUTHOR]

Many things, such as tilt effect of the piston and cylinder assembly (PCA), temperature, air buoyancy, etc., significantly affect pressure measurement results when using a pressure balance in a high-pressure measurement environment. These effects can not only increase the uncertainty of the effective area determination but also cause problems in the performance of the pressure balance. Among the above effects, the tilt of the PCA is one of the significant uncertainty sources to be considered in the calibration. In the case of two pressure balances that have exchangeable PCAs, most uncertainty sources could be eliminated by exchanging two PCAs and averaging two calibration results because symmetric behaviors can be theoretically obtained. To investigate the above effects, an oil-operated pressure balance was used to calibrate another identical pressure balance with an exchangeable PCA up to 500 MPa. Before the calibration, the vertical condition of the PCA close to the gravitational axis was determined using a precise pressure gauge by calibrating it according to the tilt angle of the pressure balance. In the case of a marginal tilt angle of the PCA, the calibration results of a cross-float method before and after exchanging two PCAs, had symmetric behaviors, but they did not follow a cosine effect. The results could be dependent on pressure, piston materials, and PCA adoption methods. In conclusion, the distortion coefficient could be changed due to the tilt since the central piston axis is not coincident with one of the cylinder anymore. [ABSTRACT FROM AUTHOR]

A High Pressure Automated Lag Time Apparatus (HP-ALTA) was used to measure the nucleation curves of Structure I (sI) – forming methane hydrate. The instrument applied a large number of constant cooling ramps to a quiescent water sample contained in a glass sample cell under isobaric conditions and recorded maximum achievable subcooling distributions. Survival curves were constructed from the measured data and nucleation curves were derived from the survival curves using the model-independent method we had recently devised. The convergence of nucleation rates with the number of experimental runs was observed after approximately 400 runs which suggests that sampling of 400 nucleation events is sufficient for the unambiguous determination of the nucleation curves. The impact of the experimental cooling rates and the approximations used in the derivation of the nucleation curves was also assessed in details. Importantly, the derived nucleation curves continuously covered over a range of 15 K. The obtained nucleation curves were then compared to the nucleation rates of methane hydrate measured at several subcoolings by Makogon and analyzed by Kashchiev and Firoozabadi. Our nucleation curves yielded nucleation rates that were broadly similar to but somewhat lower than those of Makogon and Kashchiev and Firoozabadi at the relevant subcoolings. [ABSTRACT FROM AUTHOR]

The orbital period changes of two low-mass-ratio and deep-contact binaries, FN Cam and KN Per, are investigated by using all available times of light minimum taken from the databases and literature. It is found that the orbital periods of FN Cam and KN Per show secular increase at a rate of P ˙ = 4.38 × 10 − 7 days year − 1 and P ˙ = 4.18 × 10 − 7 days year − 1 , respectively. The secular period increase suggests that FN Cam and KN Per are undergoing continuous mass transfer from the less massive secondary component to the more massive primary one. A statistical analysis of 53 low-mass-ratio and deep-contact binaries indicates that all of them should contain at least a continuous period change (secular increase/decrease or cyclic oscillation). Moreover, the rates of the secular period variations can be at a common level of P ˙ ∼ 10 − 7 days year − 1 . In addition, the cyclic period oscillation has been detected for only 43% of sample stars, which indicates that it should be not popular for all low-mass-ratio and deep-contact binaries. [ABSTRACT FROM AUTHOR]

This letter reports a first quantitative analysis of the contribution of higher partial waves in the charge symmetry breaking reaction d d → 4 He π 0 using the WASA-at-COSY detector setup at an excess energy of Q = 60 MeV . The determined differential cross section can be parametrized as d σ / d Ω = a + b cos 2 ⁡ θ ⁎ , where θ ⁎ is the production angle of the pion in the center-of-mass coordinate system, and the results for the parameters are a = ( 1.55 ± 0.46 ( stat ) + 0.32 − 0.8 ( syst ) ) pb / sr and b = ( 13.1 ± 2.1 ( stat ) − 2.7 + 1.0 ( syst ) ) pb / sr . The data are compatible with vanishing p -waves and a sizable d -wave contribution. This finding should strongly constrain the contribution of the Δ isobar to the d d → 4 He π 0 reaction and is, therefore, crucial for a quantitative understanding of quark mass effects in nuclear production reactions. [ABSTRACT FROM AUTHOR]

Metabolite interferences represent a major risk of inaccurate quantification when using LC–MS/MS bioanalytical assays. During LC–MS/MS bioanalysis of BMS-919194, a phosphate ester prodrug, in plasma samples from rat and monkey GLP toxicology studies, an unknown peak was detected in the MRM channel of the prodrug. This peak was not observed in previous discovery toxicology studies, in which a fast gradient LC–MS/MS method was used. We found out that this unknown peak would co-elute with the prodrug peak when the discovery method was used, therefore, causing significant overestimation of the exposure of the prodrug in the discovery toxicology studies. To understand the nature of this interfering peak and its impact to bioanalytical assay, we further investigated its formation and identification. The interfering compound and the prodrug were found to be isobaric and to have the same major product ions in electrospray ionization positive mode, thus, could not be differentiated using a triple quadrupole mass spectrometer. By using high-resolution mass spectrometry (HRMS), the interfering metabolite was successfully identified to be an isobaric sulfate metabolite of BMS-919194. To the best of our knowledge, this is the first report that a phosphate prodrug was metabolized in vivo to an isobaric sulfate metabolite, and this metabolite caused significant interference to the analysis of the prodrug. This work demonstrated the presence of the interference risk from isobaric sulfate metabolites to the bioanalysis of phosphate prodrugs in real samples. It is critical to evaluate and mitigate potential metabolite interferences during method development, therefore, minimize the related bioanalytical risks and ensure assay quality. Our work also showed the unique advantages of HRMS in identifying potential metabolite interference during LC–MS/MS bioanalysis. [ABSTRACT FROM AUTHOR]