Showing papers on "Mole fraction published in 2020"
01 Aug 2020
TL;DR: Two different types of H2O2 selectivity are reported for the electrochemical synthesis of H 2O2: molar fraction selectivity and Faradaic selectivity as discussed by the authors.
Abstract: Two different types of H2O2 selectivity are reported for the electrochemical synthesis of H2O2: molar fraction selectivity and Faradaic selectivity. Here we revisit their definitions and discuss the best way to report H2O2 selectivity, which can help to avoid misunderstandings or unfair performance comparisons in this growing field.
85 citations
TL;DR: In this paper, the solubility profiles of dipyridamole in pure and mixed solvents were evaluated by some thermodynamic models, including the Kamlet, Abboud and Taft Linear Solvation Energy Relationship (KAT-LSER) model.
48 citations
TL;DR: In this article, the authors used diffusion multiples made from MEAs of the quaternary Cr-Fe-Co-Ni system arranged as six distinct pseudo-binary diffusion couples.
47 citations
TL;DR: In this paper, the dissolution behavior of praziquantel in different solvent was investigated by using the isothermal equilibrium method and evaluated with the modified Apelblat equation, λh equation and Jouyban-Acree model.
44 citations
TL;DR: In this article, the equilibrium mole fraction solubility of ketoconazole in some aqueous-ethanolic mixtures was calculated using the van't Hoff and Gibbs equations.
41 citations
TL;DR: In this article, the application of sorption-enhanced steam gasification to sewage sludge treatment is experimentally investigated to generate hydrogen-rich syngas in a fixed bed setup.
Abstract: Thermal conversion is an effective non-traditional method for sewage sludge disposal. Herein, the application of sorption-enhanced steam gasification to sewage sludge treatment is experimentally investigated to generate hydrogen-rich syngas in a fixed bed setup. The main aim was to determine the optimal conditions and suitable sorbents for this process. CaO was selected as the sorbent, and different CaO sorbents were prepared via the sol-gel method. Al2O3, La2O3, and ZrO2 were used as support materials for CaO to enhance the sorbent activity and stability. The CO2 capture capacities and stabilities of the sorbents over multiple cycles were examined. Additionally, different metal additives including CoO, MgO, and CeO2 were combined with the sorbent to increase the hydrogen mole fraction and gas yield. The integration of the support material increased the stability of the sorbents over multiple cycles. High temperature increased the syngas yield and cold gas efficiency but decreased the hydrogen mole fraction. In comparison to CaO–La and CaO–Zr, CaO–Al afforded a higher hydrogen mole fraction and yield. Moreover, as Al2O3 is cheaper than La2O3 and ZrO2, it was selected as the most suitable support material for CaO, considering both its performance and cost. Transition metal Co was also investigated as a catalyst for gasification. A high Co loading ratio improved the hydrogen yield and cold gas efficiency but decreased the hydrogen mole fraction. These findings suggest that the CaO sorption-enhanced gasification to produce hydrogen-rich syngas is an appropriate method for sewage sludge disposal.
40 citations
TL;DR: In this paper, the synergistic extraction of scandium(III) with a mixture of Cyanex272 and Cyanex923 in sulfuric acid medium has been investigated, and the maximal synergistic enhancement coefficient was obtained to be 5.20.
36 citations
TL;DR: In this article, nucleate pool boiling experiments were performed on plain and five laser-textured stainless-steel foils using saturated pure water, 100% ethanol, 0.4% and 4.2% mole fraction ethanol.
Abstract: Nucleate pool boiling experiments were performed on plain and five laser-textured stainless-steel foils using saturated pure water, 100% ethanol, 0.4% and 4.2% mole fraction ethanol – water...
33 citations
TL;DR: The electrical and structural properties of V/Al-based n-contacts on n−AlxGa1−xN with an Al mole fraction x ranging from x=075 to x=095 are investigated in this article.
Abstract: The electrical and structural properties of V/Al-based n-contacts on n‐AlxGa1−xN with an Al mole fraction x ranging from x=075 to x=095 are investigated Ohmic n-contacts are obtained up to x=075 with a contact resistivity of 57×10−4 Ω·cm2 whereas for higher Al mole fraction the IV characteristics are rectifying Transmission electron microscopy reveals a thin crystalline AlN layer formed at the metal/semiconductor interface upon thermal annealing Compositional analysis confirmed an Al enrichment at the interface The interfacial nitride-based layer in n-contacts on n‐Al09Ga01N is partly amorphous and heavily contaminated by oxygen The role and resulting limitations of Al in the metal stack for n-contacts on n-AlGaN with very high Al mole fraction are discussed Finally, ultraviolet C (UVC) LEDs grown on n‐Al087Ga013N and emitting at 232 nm are fabricated with an operating voltage of 73 V and an emission power of 120 μW at 20 mA in cw operation
30 citations
TL;DR: In this paper, a synergistic extraction of scandium (III) from a spent sulfuric acid solution of titanium dioxide production by using a mixture of bis-2-ethylhexyl phosphoric acid (D2EHPA, P204) and primary amine (N1923) has been proposed.
28 citations
TL;DR: In this article, a novel experimental procedure was proposed to investigate the phase behavior of a solvent mixture (SM) with heavy oil, and a theoretical methodology was employed to estimate the phase behaviour of the heavy oil-solvent mixture (HO-SM) systems with various mole fractions of SM.
TL;DR: In this paper, the authors used the polarizable ion model to investigate the structural and transport properties of NaCl-UCl3 at various U3+ mole fractions, and found strong variation of the second coordination shells (U-U and Cl-Cl) with U 3+ mole fraction.
TL;DR: In this article, a PDF combustion model with detailed chemical kinetics was used to simulate the turbulent flames with rigorous turbulence chemistry interaction, and the results of numerical simulations were compared with experimental data.
TL;DR: In this article, the experimental solubility data of L-carnosine in different binary solvent mixtures, including water + (methanol, isopropanol or acetone), were determined in temperatures ranging from 288.05 to 323.15 K by static method under atmospheric pressure.
TL;DR: In this article, the solubility of uracil in binary solvent mixtures, including (methanol + water), (ethanol+ water) and (isopropanol plus water), was determined from 283.15 k to 318.15k by the ultraviolet spectroscopic method.
TL;DR: In this article, the authors investigated the influence of temperature, pressure and S/C (the ratio of steam to carbon) on the H2 reaction pathways and showed that the intermediate species, CH3, C2H6 and CH3OH play an important role in H2 yield.
TL;DR: In this article, the solid-liquid equilibrium solubility of thymine form AH A° at temperature from 283.15 to 323.15 K in methanol, ethanol, 1,4-dioxane, 1-butanol, acetone, 2-propanol, acetonitrile, N,N-dimethylformamide (DMF), 2-butanone and two mixed solvents were reported, solvent effect in mono-solvent systems, preferential solvation in mixed solvent systems, thermodynamic properties and model correlation parameters.
TL;DR: In this article, the solvents were measured at the eutectic point in the temperature range from 278.15 to 373.15 K. All systems present densities and viscosities higher than water, which is directly related to the strong interactions between the components.
Abstract: Despite some promising potential applications of eutectic systems containing choline chloride ([Ch]Cl) and a polyalcohol, a detailed investigation of the thermodynamic behavior of these systems is still missing. In this work, the solid–liquid equilibria phase diagrams of binary systems containing [Ch]Cl and one from six different polyalcohols (ethylene glycol (EG), 1,3-propanediol, glycerol (Gly), meso-erythritol, xylitol, and sorbitol) were measured in the full composition. Except for the mixtures with Gly or EG, a quasi-ideal behavior in the [Ch]Cl solubility curve is observed. In the polyalcohol solubility curve, the mixtures present small negative deviations from ideality, except for [Ch]Cl + EG, which is slightly positive. The solid–liquid phase diagrams show a large liquid composition window, and not a fixed stoichiometry for the eutectic points, where the mixtures can be used as solvents close to, or below, room temperature. Aiming at their application, viscosities and densities were measured at the eutectic point in the temperature range from 278.15 to 373.15 K. All systems present densities and viscosities higher than water, which is directly related to the strong interactions between the components. Solvatochromic parameters were measured to characterize the solvents, and they show that solvent tunability can be achieved by varying the polyalcohol mole fraction.
TL;DR: In this article, the hydrogen-bonding interactions between metal-based ionic liquids and methanol at different concentration were studied by using excess infrared spectroscopy, density functional theory (DFT) and molecular dynamics (MD) simulations.
TL;DR: In this paper, the solubility of gliclazide in five different binary solvent mixtures was measured in the temperature rang 278.15-318.15 k and at atmospheric pressure by a gravimetric method.
TL;DR: This paper shows how the analysis of the coincident mass-tagged Threshold PhotoElectron Spectra (TPES) together with first principle computations, consisting of the determination of the adiabatic ionization energies and the spectra of some products, may assist products' identification.
Abstract: Through the use of tunable vacuum ultraviolet light generated by the DESIRS VUV synchrotron beamline, a jet-stirred reactor was coupled for the first time to an advanced photoionization mass spectrometer based upon a double imaging PhotoElectron PhotoIon COincidence (i2PEPICO) scheme. This new coupling was used to investigate the low-temperature oxidation of n-pentane, a prototype molecule for gasoline or Diesel fuels. Experiments were performed under quasi-atmospheric pressure (1.1 bar) with a residence time of 3 s for two equivalence ratios (1/3 and 0.5) with a fuel initial mole fraction of 0.01. The measured time-of-flight mass spectra are in good agreement with those previously obtained with other photoionization mass spectrometers and, like those previous ones, display several m/z peaks for which the related species assignation is ambiguous. This paper shows how the analysis of the coincident mass-tagged Threshold PhotoElectron Spectra (TPES) together with first principle computations, consisting on the determination of the adiabatic ionization energies and the spectra of some products, may assist products identification. The results mostly confirm those previously obtained by photoionization mass spectrometry and gas chromatography, but also allow a more accurate estimation of the 1-pentene/2-pentene mole fraction ratio. Our data also indicate a higher formation of acetone and methyl ethyl ketone than what is predicted by current models, as well as the formation of products, not previously taken into account, such as methoxyacetylene, methyl vinyl ketone or furanone. The formation of three, four and five membered ring cyclic ethers is confirmed along with linear ketones: 2- and 3-pentanone. A significant general trend in indicating higher amounts of ketones than gas chromatography is noted. Finally, TPES of alkenylhydroperoxides are also provided for the first time and constrains on the isomers identification are provided
TL;DR: It is concluded that average pore aperture, not solvent‐linker chemical interactions, is the primary factor responsible for the different diffusion dynamics upon introduction of an amino group to the linker.
Abstract: Understanding the factors that affect self-diffusion in isoreticular and multivariate (MTV) MOFs is key to their application in drug delivery, separations, and heterogeneous catalysis. Here, we measure the apparent self-diffusion of solvents saturated within the pores of large single crystals of MOF-5, IRMOF-3 (amino-functionalized MOF-5), and 17 MTV-MOF-5/IRMOF-3 materials at various mole fractions. We find that the apparent self-diffusion coefficient of N,N-dimethylformamide (DMF) may be tuned linearly between the diffusion coefficients of MOF-5 and IRMOF-3 as a function of the linker mole fraction. We compare a series of solvents at saturation in MOF-5 and IRMOF-3 to elucidate the mechanism by which the linker amino groups tune molecular diffusion. The ratio of the self-diffusion coefficients for solvents in MOF-5 to those in IRMOF-3 is similar across all solvents tested, regardless of solvent polarity. We conclude that average pore aperture, not solvent-linker chemical interactions, is the primary factor responsible for the different diffusion dynamics upon introduction of an amino group to the linker.
TL;DR: In this article, the effects of adding H2 to fuel on the formation of soot are studied numerically and experimentally in a laminar coflow C2H4 diffusion flame burning in 30%O2-70%CO2 atmosphere by applying the open source flame code CoFlame and two-dimensional light-of-sight attenuation (2D-LOSA) diagnostic, respectively.
TL;DR: In this article, a system of zinc tellurite glasses with chemical composition (TeO2)0.70 (ZnO0.30]1-x (Nd2O3 NPs)x, where x ranged from 0.01 to 0.05 molar fraction have been prepared and coded as TZND have been fabricated using the melt-quenching technique.
Abstract: A system of zinc tellurite glasses with chemical composition [(TeO2)0.70 (ZnO)0.30]1-x (Nd2O3 NPs)x, where x ranged from 0.01 to 0.05 molar fraction have been prepared and coded as TZND have been fabricated using the melt-quenching technique. The aim was to study the structural, physical, and optical properties of the sample glasses. The choice of the chemical composition was to provide high refractive index, favourable metallization criterion and other optical qualities for linear and non-linear optical applications. The optical properties were studied using the UV–Vis spectroscopic analysis. The density and molar volume were found to increase with Nd2O3 NPs concentration. The FTIR spectral analysis showed the existence of TeO3 and TeO4 structural units which varying concentrations of TeO4 observed with Nd2O3 nanoparticles (NPs). The transmission electron microscopy (TEM) analysis showed the agglomeration of the Nd2O3 NPs in the morphological structure of the glasses. The variations of the optical parameters were mostly related to the variation in the structural nature of the glasses (TeO3 and TeO4 concentration changes). High refractive index value, ranging between 2.5470 and 2.6093, favourable metallization criterion value range of 0.3406 and 0.3535 as well as high polarizabilities and the optical basicity reveal that the glasses have high potential in optical fibre technology as well as optical non-linear (laser) applications.
TL;DR: In this paper, the equilibrium solubility at temperatures from (278.15 to 318.15) K, dissolution thermodynamics, preferential solvation, and apparent specific volume at saturation of sulfacetamide (SCM) in {propylene glycol (PG) (1) + water (2)} mixtures is reported.
TL;DR: In this article, a robust kinetic model for describing the oxidation of a fuel, knowledge of different physicochemical parameters such as ignition delay times (IDTs) and laminar burning velocities or intrinsic local parameters like species mole fraction profiles is essential.
TL;DR: In this paper, the equilibrium solubility at five temperatures from (293.15 to 313.15) K, apparent dissolution, mixing and solvation thermodynamics, and apparent specific volume at saturation of acetaminophen (ACP) in {ethanol (EtOH) (1) + propylene glycol (PG) (2) + water (3)} mixtures is reported.
TL;DR: In this article, the solubility of cefixime is studied in three aqueous solutions of deep eutectic solvents (DESs), including choline chloride+malonic acid, choline oxide+urea, and choline acid+glucose.