Thermodynamic properties of n-pentane

Grigoryev, B. A.; Rastorguyev, Y. L.; Kurumov, D. S.; Gerasimov, A. A.; Kharin, V. E.; Плотников, С.А.

doi:10.1007/bf00500841

Cited by 7 publications

(3 citation statements)

References 19 publications

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“…19 Other properties of interest are, quite naturally, thermodynamic, structural, and dynamic functions of all kind 7,9,12,16,17 ͑heat capacities, specific volumes, electric polarizability, intermolecular interactions, gyration radius, rotational relaxation time, heat flux-, velocity-, stress-, or pressure-autocorrelation functions, diffusion self-coefficients, viscosities, ...͒. It is therefore the purpose of this study to evaluate the conformational energy differences of this molecule by means of a focal point analysis similar to that carried out by Allinger et al 5 for n-butane.…”

Section: Introductionmentioning

confidence: 99%

High-level theoretical study of the conformational equilibrium of n-pentane

Salam¹,

Deleuze²

2002

The Journal of Chemical Physics

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High level theoretical study of the structure and rotational barriers of trans-stilbene An accurate calculation of the energy differences between stationary points on the torsional potential energy surface of n-pentane is performed using ab initio Hartree-Fock theory, advanced many-body methods such as MP2, MP3, CCSD, and CCSD͑T͒, as well as density functional theory, together with basis sets of increasing size. This study focuses on the four conformers of this compound, namely, the all staggered trans-trans ͑TT͒, trans-gauche ͑TG͒, gauche-gauche (G ϩ G ϩ ), and gauche-gauche (G ϩ G Ϫ ) structures, belonging to the C 2v , C 1 , C 2 , and C 1 symmetry point groups, respectively. A focal point analysis up to 635 basis functions is carried out to determine when the series of relative energies of the four conformers approach convergence. It is found that relative to the minimum energy TT conformer, the energy differences of the TG, G ϩ G ϩ , and G ϩ G Ϫ conformers obtained from ab initio methods are 0.621, 1.065, and 2.917 kcal mol Ϫ1 , respectively. Converged energy differences obtained with three density functionals, B3PW91, B3LYP, and MPW1K, are found to be considerably higher than those computed ab initio. Mole fractions of the various conformers are evaluated at different temperatures from thermostatistical data accounting for vibrational and rotational entropies, as well as zero-point vibrational energies in the rigid rotor-harmonic oscillator approximation.

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Section: Introductionmentioning

confidence: 99%

High-level theoretical study of the conformational equilibrium of n-pentane

Salam¹,

Deleuze²

2002

The Journal of Chemical Physics

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“…It is helpful to discover the change rule of oil sand production, reveal the influence mechanism of oil sand production, and deepen the understanding of the oil sand production process. Initially, V g 0 is the volume of the dry carrier gas required to wash and extract the solute sample at 0 • C. The following formula (1-3) is used for the research [37].…”

Section: Thermodynamic Methodsmentioning

confidence: 99%

“…Initially, V g 0 is the volume of the dry carrier gas required to wash and extract the solute sample at 0 °C. The following formula (1–3) is used for the research [ 37 ].

where,

and, W L is the mass (g) of the stationary phase (bitumen) in the column,

is the net retention volume (cm 3 ),

is the corrected retention volume (cm 3 ),

is the mobile phase volume(cm 3 ),

is the retention volume (cm 3 ), V a is the adjusted retention volume (cm 3 ), Fc is the carrier gas flow rate (cm 3 /min),

is the measured flow rate(cm 3 /min),

is the column temperature,

is the flow meter temperature, t R is the retention time (min) for a solute; t A is the column dead time (min); j is the compressibility correction factor; p o is the outlet pressure (Pa); and p i is the pressure of the carrier gas at the inlet to the GC column.…”

Section: Research Approachmentioning

confidence: 99%

Thermodynamic Properties Investigation of Process Volatile Organic Compounds (VOCs) and Its Transport Impact Factor in Oil Sands Management

et al. 2021

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This paper presents a new approach for the determination of volatile organic compounds (VOCs) characteristics and their migration influencing factors in oil sands management processes and reveals the relationship between different asphaltene content and different solvents. Specifically, thermodynamic (i.e., partitioning coefficients, Kr, specific retention volume, Vg, the activity coefficients, γ and enthalpy of solution, ΔH0) and their impact factors are discussed. Gas-liquid chromatography (GLC) experimental measurements were used as the test data. A range of solvents (nC5, iC5, nC6, nC7, and Toluene) has been tested in different asphalt contents (0, 2.56, 9.93, 36.86, 53.67 wt%). There are temperatures in the range of 333.2–393.2 K (with 10 K increase) were conducted, respectively. The dynamics properties of asphalt mixture are calculated, and the relation between dynamics properties of asphalt mixture and absolute temperature, asphalt content and solvent type is discussed. The results show that within the acceptable error range, partitioning coefficients, Kr, specific retention volume, Vg, and enthalpy of solution, ΔH0 and other thermodynamic properties have a good tendency to predict, they decrease with the increase in asphaltene content and temperature and increase with the increase in solute carbon number.

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Berechnungsmethoden für Stoffeigenschaften

Lucas

Luckas

2002

VDI-Wärmeatlas

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Thermodynamic properties of n-pentane

Cited by 7 publications

References 19 publications

High-level theoretical study of the conformational equilibrium of n-pentane

High-level theoretical study of the conformational equilibrium of n-pentane

Thermodynamic Properties Investigation of Process Volatile Organic Compounds (VOCs) and Its Transport Impact Factor in Oil Sands Management

Berechnungsmethoden für Stoffeigenschaften

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