On the volumetric properties of 2-hydroxy ethylammonium formate ionic liquid under high-pressures: Measurement and molecular dynamics

This work aims to report not only the new measurement for densities of 2-hydroxy ethylammonium formate (2-HEAF) ionic liquid under high-pressures but also molecular dynamics considerations of nanoscopic characterization for physicochemical properties in the pressure range studied. High-pressure densities of 2-HEAF showed smooth trends with temperature and pressure variations. Measurements were carried out at temperatures T = (298.15 to 333.15) K and at pressures P = (0.1 to 40) MPa. The high-pressure densities of 2-HEAF have also been correlated by the use of Tait equation with AARD equal to 0.031% and the mechanical coefficients including the isothermal compressibility, isobaric expansivity and thermal pressure were estimated. Molecular dynamics simulations were carried out in the same pressure – temperature range as the experimental study. Force field was validated against experimental results and the microscopic structure was analyzed in terms of intermolecular interactions and their evolution with temperature and pressure.Iran National Science Foundation for supporting this project via the grant number (INSF-96000966

Tuning the properties of ionic liquids by mixing with organic solvents: The case of 1-butyl-3-methylimidazolium glutamate with alkanols

Binary liquid mixtures of 1-butyl-3-methylimidazolium glutamate acid ([bmim][glu]) with alkanols (1-propanol, isobutanol and 1,2-propanediol) are studied in the full composition range as a function of temperature using a combined experimental and computational chemistry approach. Experimental thermophysical information as well as derived excess and mixing properties allowed to characterize these complex liquid mixtures in terms of deviation from ideality as well their relationships with the developed intermolecular forces and changes with the type of considered alkanols. Theoretical studies using quantum chemistry and classical molecular dynamics simulations provided nanoscopic characterization on the studied fluids, with particular attention to the extension and nature of hydrogen bonding and its effects on molecular arrangements and mixed fluids’ properties. The reported study provides a micro and macroscopic characterization of the considered aminoacid-based ionic liquid mixtures, thus contributing to the knowledge of sustainable ionic liquid systems mixed with organic solvents for fine tuning properties and developing task specific applications.Shiraz University of Technology and Ministerio de Ciencia, Innovación y Universidades (Spain, project RTI2018-101987-B-I00)

Experimental and molecular modeling study on the binary mixtures of [EMIM][BF4] and [EMIM][TFSI] ionic liquids

The properties of [EMIM][BF4] + [EMIM][TFSI] double salt ionic liquid (DSIL) were studied as a function of mixtures composition and temperature. Experimental physicochemical properties combined with molecular simulation (quantum chemistry and classical molecular dynamics) were considered, thus providing a micro and macroscopic characterization of fluids’ structuring, intermolecular forces and molecular aggregation. The results were analysed in thermodynamics terms considering deviations of ideality and mixing properties as well as from the solvation and interaction between the involved ionic liquids by the developed complex hydrogen bonding networks. Likewise, liquid [EMIM][BF4] + [EMIM][TFSI] interfaces (x[EMIM][BF4] = x[EMIM][TFSI] = 0.5) were also studied using molecular dynamics methods to examine the diffusion of [BF4]- and [TFSI]- anions in the [EMIM][BF4] + [EMIM][TFSI] liquid interface, and the mechanism of interface crossing. The results allow a multiscale characterization of the considered ionic liquid mixtures thus providing another way of designing IL-type solvents for specific applications, by choosing not only the ion identity but also the ion ratio.Ministerio de Ciencia, Innovación y Universidades (Spain, project RTI2018-101987-B-I00) and by Junta de Castilla y León (Spain, project BU094G18). We acknowledge SCAYLE (Supercomputación Castilla y León, Spain) for providing supercomputing facilities

A review of refrigerant R1234ze(E) recent investigations

[EN] Climate change is demonstrated through global surface temperatures increase in the last century. To stop this phenomenon, new regulations that ban or tax greenhouse gas fluids (HFC among them) have been approved. In the medium term, only low-GWP refrigerants will be permitted in developed countries. HFO fluids and most used HFCs as refrigerants in HVACR systems possess similar thermophysical properties. Among them, one of the most promising is R1234ze(E). This refrigerant presents good environmental properties and can be used in most of HVACR applications, pure or mixed with HFC or natural refrigerants (mainly CO2). This paper collects the most relevant research about R1234ze(E) thermophysical and compatibility properties, heat transfer and pressure drop characteristics, and vapor compression system performance; separating those works that consider R1234ze(E) pure or blended. Once the available literature is analyzed, it can be concluded that pure R1234ze(E) is a good option only in new HVACR systems. Nevertheless, if it is combined with other refrigerants, the final GWP value is also considerably reduced, maintaining efficiency parameters at levels that allow them to replace R134a, R404A or R410A in existing systems with minor modifications.The authors thankfully acknowledge the “Ministerio de Educación, Cultura y Deporte” (Grant Number FPU12/02841) for supporting this work through “Becas y Contratos de Formación de Profesorado Universitario del Programa Nacional de Formación de Recursos Humanos de Investigación del ejercicio 2012”.Mota-Babiloni, A.; Navarro-Esbrí, J.; Molés, F.; Barragán Cervera, Á.; Peris, B.; Verdú Martín, GJ. (2016). A review of refrigerant R1234ze(E) recent investigations. Applied Thermal Engineering. 95:211-222. https://doi.org/10.1016/j.applthermaleng.2015.09.055S2112229

Measurement and modeling of volumetric properties and speeds of sound of several mixtures of alcohol liquids containing butanediol

Densities and speeds of sound for the pure as well as binary mixtures of 1,2-butanediol and benzyl alcohol, 2-phenylethanol, 2-butanol, and 1,3-butanediol were measured over the 0 to 1 composition range and at six different temperatures between 298.150 K and 323.150 K with an interval of 5 K and at atmospheric pressure using a vibrating tube densimeter.The experimental values were used to calculate excess molar volume, VmE, excess isentropic compressibility, KSE, excess thermal expansion coefficient, αpE, infinite partial molar volumes, V̅i∞ and excess partial molar volumes at infinite dilution, V̅iE,∞. The sign and magnitude of mixing quantities have been used to discuss the nature and strength of molecular interactions in binary mixtures. The calculated excess values and deviation quantities were fitted to the Redlich–Kister polynomials equation. Furthermore, it has been checked how the calculated values of densities and excess molar volumes using the Tao–Mason equation of state compare with the experimental ones.Mohammad Mehdi Alavianmehr, Somayeh Shahsavar, Hanieh Ghodrati and Nahid Hemmat

Impact of donor KIRs and recipient KIR/HLA class I combinations on GVHD in patients with acute leukemia after HLA-matched sibling HSCT.

In addition to T cells, NK cells can also participate in the outcome of hematopoietic stem cell transplantation (HSCT) mainly through the interaction between donor killer cell immunoglobulin-like receptors (KIRs) and recipient human leukocyte antigen (HLA) class I molecules. There is a risk of GVHD other than leukemia relapse after allogeneic HSCT that activation of donor NK cells in the absence of appropriate inhibitory ligands will be one of the reasons. To investigate the impact of donor KIRs and recipient KIR/HLA class I combinations on GVHD and leukemia relapse in patients with acute leukemia after HSCT, 100 patients with acute leukemia who received HSCT from their HLA-matched siblings were included in this study. Genotypes of 16 KIR genes and two 2DS4 variants (full length and deleted alleles), along with HLA-A/B genotypes, were determined by PCR-SSP. HLA-C genotyping was done with the SSO-Luminex method. Chimerism analysis was done using 16 short tandem repeats (STRs) to detect early leukemia relapse. Acute (a)GVHD occurred in 38 patients, and 16 of them died during the study. None of the recipients showed any sign of leukemia relapse after HSCT. Full donor chimerism was observed in all tested patients during the first year after HSCT. Our results also indicated an increased risk of aGVHD in AA recipients with the C2/Cx, Bw4+ (or A-Bw4+) or HLA-A3-/A11- genotypes who received HSCT from Bx donors. Our results showed that donor selection based on donor-recipient KIR genotypes and recipient HLA class I status can improve the outcome of HSCT

Excess molar volumes, excess thermal expansion coefficients and isentropic compressibility deviations for binary mixtures of benzyl alcohol + (1-butanol, 2-butanol, 2-methyl-1-butanol and <i>tert</i>-butanol) at <i>T</i> = (298.15-328.15) K and ambient pressure

<p>In the present paper, we report the density (<i>ρ</i>) and ultrasonic speed (<i>u</i>) of four binary mixtures of benzyl alcohol with 1-butanol, 2-butanol, 2-methyl-1-butanol and <i>tert</i>-butanol over the temperature range 298.15–328.15 K and ambient pressure, covering the entire composition range, expressed by the mole fraction (<i>x</i>₁) of benzyl alcohol. The experimental data on density and ultrasonic speed were used to calculate the excess molar volumes, , deviations in isentropic compressibility, , excess thermal expansion coefficients, , excess partial molar volumes, , and excess partial molar volumes at infinite dilution, . The results obtained were used to investigate the nature and strength of intermolecular interactions in these mixtures. The calculated quantities , and are well correlated with the Redlich–Kister equation.</p