Showing papers on "Standard molar entropy published in 2013"
TL;DR: In this article, the authors reported on the efficient adsorption for uranium by metal-organic frameworks (MOFs) HKUST-1 from aqueous solution, and the results showed that the equilibrium data fitted well to Langmuir model in the studied range of uranium concentration (10 mg/l-800 mg/L) and temperature (298 K-318 K).
120 citations
TL;DR: The studies of kinetics and thermodynamics of adsorption of Ethidium bromide in aqueous solutions on single-walled carbon nanotube (SWCNT) and carboxylate group functionalized single-Walledcarbon nanotubes ( SWCNT-COOH) surfaces were by UV-Vis spectroscopy, and the values of ΔH0 and ΔG0 suggested that the adsorptions was endothermic and spontaneous.
72 citations
TL;DR: In this article, the authors provided a critical study on the adsorption of boron by electrochemically generated zinc hydroxide, and the results showed that the optimum removal efficiency of 93.2% was achieved at a current density of 0.2
68 citations
TL;DR: The thermal expansion coefficient, molecular volume, standard entropy, and lattice energy of pure ionic liquid n-butylammonium nitrate (N4NO3) and its binary mixtures with methanol, ethanol, 1-propanol, and 1-butanol were derived from the experimental density results as discussed by the authors.
58 citations
TL;DR: The physicochemical behavior of antibiotic amphiphilic drug pefloxacin mesylate (PFM) and its interaction with anionic surfactant, sodium dodecyl sulfate (SDS) was reported in this paper.
52 citations
TL;DR: In this paper, the density and surface tension of pure ionic liquid 1-butyl-3-methyl-imidazolium l -lactate were measured from T (293.15 to 343.15) K at atmospheric pressure.
50 citations
TL;DR: In this article, the authors reported the oxygen electro-reduction in air-saturated acetonitrile (MeCN) solution supported by 0.1-M tetra-n-butylammonium perchlorate salt under two experimental conditions: (1) anhydrous MeCN at elevated temperatures from 298.5 to 313.0
50 citations
TL;DR: In this article, the effects of methylene and methyl groups to density, dynamic viscosity, and electrical conductivity of air and water stable hydrophobic ionic liquids (ILs) were discussed.
49 citations
TL;DR: The calculated thermodynamic parameters suggest the dehydration of hydrophobic part of the drug at higher temperatures (>313K), not only in case of AMT but also in the presence of [C8mim][Cl].
46 citations
TL;DR: In this paper, the authors measured the solubility of 3,4-dichloronitrobenzene in methanol, ethanol, and liquid mixtures (methanol + water, ethanol + water) at 101.3 kPa by gas chromatography.
Abstract: The solubilities of 3,4-dichloronitrobenzene in methanol, ethanol, and liquid mixtures (methanol + water, ethanol + water) were measured in the temperature range of (278.15 to 303.15) K at 101.3 kPa by gas chromatography. The solubility of 3,4-dichloronitrobenzene in the binary mixed solvents increased with both increasing temperature and mass fraction of organic solvents. The measured solubility was correlated by the van’t Hoff equation, the modified Apelblat equation, and the λh equation. The correlated results indicated that the calculated solubility using the modified Apelblat equation had a closer agreement with the experimental data than those using the other two models. According to the measured solubility, the thermodynamic properties of dissolution of 3,4-dichloronitrobenzene, including the Gibbs free energy change of solution, molar enthalpy of dissolution, and molar entropy of dissolution, were calculated by using the modified Apelblat model.
44 citations
TL;DR: In this paper, the effect of various experimental parameters such as initial dye concentration (50-500 mg/L), contact time (0-32 h), pH (2-12), and temperature (30-50°C) were investigated.
Abstract: Activated carbon was prepared through a chemical activation of bamboo waste precursor (BMAC) using phosphoric acid as the activating agent at 500°C for 2 h. Batch adsorption studies were carried out for the adsorption of C.I. Reactive Black 5 (RB5) onto the BMAC. The effect of various experimental parameters such as initial dye concentration (50–500 mg/L), contact time (0–32 h), pH (2–12), and temperature (30–50°C) were investigated. Equilibrium data were found to be very well represented by the Freundlich isotherm and a pseudo-second-order model was found to explain the kinetics of RB5 adsorption more effectively. The mechanism of the adsorption process was determined by the intraparticle diffusion model. Thermodynamic parameters such as standard enthalpy (ΔH°), standard entropy (ΔS°), standard free energy (ΔG°), and activation energy were determined. The results indicated that BMAC is a suitable adsorbent material for adsorption of reactive dye from aqueous solutions.
TL;DR: In this article, an amino acid based ionic liquid [Bmim][Asp], 1-butyl-3-methylimidazolium aspartate, and a binary mixture system composed of methanol and amino acid were synthesized and prepared, respectively.
Abstract: An amino acid based ionic liquid [Bmim][Asp], 1-butyl-3-methylimidazolium aspartate, and a binary mixture system composed of [Bmim][Asp] and methanol were synthesized and prepared, respectively. The density, surface tension, and electrical conductivity of the pure IL and the binary system were measured or estimated by the extrapolation method at different temperatures. The physicochemical properties of the IL or the binary system like the molecular volume, standard molar entropy, lattice energy, parachor, speed of sound, molar enthalpy of vaporization, interstice volume, thermal expansion coefficient, excess volume, and so forth were estimated by empirical and semiempirical equations. The glass transition temperature was determined by the differential scanning calorimetry (DSC). The status of intermolecular interaction based on the excess volume change of the IL mixture was discussed at 298.15 K. By Vogel–Fulcher–Tamman (VFT) and Castell–Amis (CA) equations, the relationship between the electrical conduct...
TL;DR: In this paper, the critical micelle concentration (cmc) of sodium dodecyl sulphate (SDS) was determined from plots of specific conductance of SDS.
TL;DR: Electronic evaluation of interfacial compositions and thermodynamic properties of w/o mixed surfactant microemulsions and insight into the nature of the oil/water interfaces of these systems is provided by conductivity and dynamic light scattering studies as a function of ω and X(Brij-35).
TL;DR: The linear polarizabilities and first hyper polarizability of the molecule indicate that the compound is a good candidate of nonlinear optical materials.
TL;DR: In this article, the heat capacities of FePO4 and Fe3(P2O7)2 have been measured using a Quantum Design Physical Property Measurement System (PPMS) over the temperature range from (2 to 300) K. The thermodynamic functions, magnetic heat capacities, and magnetic entropies of these two compounds were calculated based on curve fitting of the experimental heat capacity values.
TL;DR: In this paper, the authors presented the heat capacities of the four lithium silicide phases Li 12 Si 7, Li 7 Si 3, Li 13 Si 4, and Li 22 Si 5 /Li 21 Si 5 as a function of temperature over the range from (2 to 873) K. The measurements were carried out using three different calorimeters.
TL;DR: In this paper, the heat capacity of a synthetic two-line ferrihydrite, which showed typically broad X-ray diffraction peaks due to small particle size and/or disorder but had a rather low excess water content, FeOOH·0.027H2O, was measured over the temperature range of (2 to 300) K. The fit required an anisotropic ferrimagnetic spin wave component.
TL;DR: It turns that the hybrid PBE1PBE functional with 6-311+G(d,p) basis provide reliable λ(max) when solvent effects are included in the model, and the NBO analysis reveals that the studied compound presents a structural characteristic of electron-transfer within the compound.
TL;DR: In this paper, the thermochemistry of α-D-xylose(cr) was studied by means of oxygen bomb calorimetry and a Physical Property Measurement System (PPMS) in zero magnetic field.
TL;DR: In this article, the authors investigated the thermal conductivity, Young's modulus, Debye temperature, Vickers hardness, and heat capacity of Th1−x U x O2 solid solutions.
Abstract: Th1−x U x O2 solid solutions were synthesized by solid-state reaction and pelletized using the spark plasma sintering (SPS) technique. Pellets with >90% theoretical density were easily obtained within 40 min of sintering without any additive. The thermal conductivity, Young's modulus, Debye temperature, Vickers hardness, and heat capacity were systematically investigated, and the values for ThO2 agree with the literature data. The thermal conductivity of Th1−x U x O2 decreased with increasing U content up to x =∼0.5. This tendency corresponds to phonon-point defect scattering theory. The Young's modulus and Debye temperature linearly decreased with increasing U content. The Debye temperature and standard molar entropy derived from the low-temperature heat capacity agree with the reported values.
TL;DR: The coefficient of compressibility of a binary mixture of water and glycol was measured at pressures from 0.1 to 100 MPa and temperatures from 278.15 to 323.15 K.
TL;DR: In this article, the conductance, FTIR as well as 1H NMR analysis for well known synthetic antioxidant; butylated hydroxyanisole (BHA) and anionic surfactant; sodium dodecyl sulfate (SDS).
TL;DR: In this paper, the authors measured the solubility of gallic acid in (water + methanol) binary solvents from (293.15 to 318.15) K at atmospheric pressure using a thermostated reactor and UV/vis spectrophotometer analysis.
TL;DR: In this article, the effects of substituent groups in carboxylate anions on densities and surface tensions of these ionic liquids have been assessed from the analysis of the structure-property relat...
Abstract: In this work, four 1-butyl-3-methylimidazolium carboxylate ionic liquids (ILs) with different substituent groups in anions, including 1-butyl-3-methylimidazolium glycollate [C4mim][HOCH2COO], 1-butyl-3-methylimidazolium lactate [C4mim][CH3CHOHCOO], 1-butyl-3-methylimidazolium benzoate [C4mim][C6H5COO], and 1-butyl-3-methylimidazolium glycinate [C4mim][H2NCH2COO], have been synthesized and characterized. Their densities (ρ) and surface tensions (γ) have been determined experimentally in the temperature range of (298.15 to 343.15) K. By using thermodynamic and empirical equations, molar volume (Vm), isobaric expansivity (αp), standard entropy (S°), lattice energy (UPOT), surface excess entropy (Ss), vaporization enthalpy (ΔlgHm0) and Hildebrand solubility parameter (δH) of these ILs have been derived from density and surface tension data. The effects of substituent groups in carboxylate anions on densities and surface tensions of these ILs have been assessed from the analysis of the structure–property relat...
TL;DR: In this article, the solubility of glycine in different compositions of ethanol-water binary solvent mixtures was measured over the temperature range of (278.15-328.15) K at intervals of 5.00 K by employing an analytical stirred-flask method.
TL;DR: In this article, the relationship between thermodynamic properties of nano CaMoO4 and bulk CaOO4 was built through designing a novel thermochemical cycle and combined with in situ microcalorimetry.
TL;DR: In this article, the association characteristics of phenothiazine drugs Fluphenazine and Trifluperazine dihydrochloride in water have been examined and their thermodynamic parameters have been calculated using conductometry.
Abstract: Association characteristics of amphiphilic phenothiazine drugs Fluphenazine and Trifluperazine dihydrochloride in water have been examined and their thermodynamic parameters have been calculated using conductometry. The electrical conductivity was measured as a function of concentration at various temperatures and cmc was calculated in the temperature range of 20-50C. Thermodynamic parameters i.e. standard free energy of micellization,mG , standard enthalpy of micellization, m H and standard entropy of micellization, m S were calculated from cmc value using closed association model.
TL;DR: The results showed that the pseudo-second order model expressed the kinetic data better than the Freundlich isotherm model, and indicated that the adsorption process was spontaneous, exothermic, and feasible.
TL;DR: In this article, the authors measured the solubility of xylitol in ethanol+water solvent mixtures at temperatures ranging from 278.00 to 323.00 K at atmospheric pressure by using a laser technique and correlated the results with the combined nearly ideal binary solvent CNIBS/Redlich-Kister equation.
Abstract: The solubility of xylitol in ethanol+water solvent mixtures was measured at temperatures ranging from 278.00 K to 323.00 K at atmospheric pressure by using a laser technique. The results of these measurements were correlated by the combined nearly ideal binary solvent CNIBS/Redlich-Kister equation. The experimental solubility and correlation equation in this work can be used as essential data and models in the purification process of xylitol. The variant 2 in the CNIBS/R-K models was confirmed to be more adaptable to predict solubility of xylitol in binary ethanol +water system. Using the experimentally measured solubilities, the thermodynamic properties of dissolution of xylitol, such as Gibbs energy, molar enthalpy of dissolution, and molar entropy of dissolution, were calculated.