Mutual Diffusion Coefficients for the Systems HD–N2 and HD–Ar at 1 atm Pressure and 300 K

1973 ◽  
Vol 51 (19) ◽  
pp. 2101-2107 ◽  
Author(s):  
K. R. Harris ◽  
T. N. Bell
Keyword(s):  
Diffusion Coefficient ◽  
Diffusion Coefficients ◽  
Experimental Error ◽  
Mutual Diffusion ◽  
Intermolecular Potentials ◽  
Mass Effects

Mutual diffusion coefficients, D12, have been measured as a function of concentration for the systems HD–N2 and HD–Ar at 1 atm pressure and 300 K. The data are compared with previously published measurements for the corresponding H2 and D2 containing systems. After the estimated uncertainties due to experimental error and impurities, and corrections due to quantum and mass effects are taken into account, the mass corrected diffusion coefficient, [Formula: see text], for each system is found to lie above those of the corresponding H2 and D2 systems by up to 2%. These effects are attributed to differences in the intermolecular potentials of H2, D2, and HD.

The Concentration Dependences of the Binary Diffusion Coefficients of the Systems H2–Ne, D2–Ne, H2–N2, D2–N2, H2–Ar, and D2–Ar at 1 Atm Pressure and 300 K

1972 ◽  
Vol 50 (14) ◽  
pp. 1644-1647 ◽  
Author(s):  
K. R. Harris ◽  
T. N. Bell ◽  
Peter J. Dunlop
Keyword(s):  
Mole Fraction ◽  
Diffusion Coefficients ◽  
Experimental Error ◽  
Similar Data ◽  
Enskog Theory ◽  
Intermolecular Potentials ◽  
Binary Diffusion ◽  
Concentration Dependences ◽  
Binary Diffusion Coefficients

Binary diffusion coefficients have been measured as a function of concentration for the systems H2–Ne, D2–Ne, D2–N2, H2–Ar, and D2–Ar at 1 atm pressure and 300 K. Similar data have already been presented for the system H2–N2. As predicted by the Chapman–Enskog theory, the concentration dependences of the diffusion coefficients for the systems containing deuterium are somewhat less than for the corresponding systems containing hydrogen. The data for the systems containing Ne and N2 indicate that there may be differences between the parameters required to describe the assumed spherical intermolecular potentials for the systems H2–Ne and D2–Ne, and also for the systems H2–N2 and D2–N2. The concentration dependences of the diffusion coefficients of all six systems are, within the estimated experimental error of ±0.2%, linear in the mole fraction of the heavier component in each system, x2.

High-Dilution Diffusion of K + , Rb + , Cs + , and Tl + in the Molten System (Li-K)NOs Studied by Wave-Front-Shearing Interferometry

1979 ◽  
Vol 34 (4) ◽  
pp. 504-509 ◽  
Author(s):  
Osamu Odawara ◽  
Isao Okada ◽  
Kazutaka Kawamura
Keyword(s):  
Diffusion Coefficient ◽  
Wave Front ◽  
Diffusion Coefficients ◽  
Free Space ◽  
Experimental Error ◽  
Positive Deviation ◽  
High Dilution ◽  
Ionic Radii ◽  
Shearing Interferometry ◽  
Wide Range

The high-dilution diffusion coefficients of K+, Rb+, Cs+, and Tl+ in molten LiNO3-KNO3 mixtures are measured over a wide range of temperatures and concentrations by means of wavefront- shearing interferometry. A slightly positive deviation from linearity is found for the concentration dependence of the diffusion coefficient of K+ , Rb+, and Tl+, while no deviation is found for Cs+ within the experimental error. This is qualitatively discussed from the viewpoint of the ionic radii, the free space in the solvent, and the interaction between the diffusing and the surrounding ions

The mutual diffusion coefficient of ethanol–water mixtures: determination by a rapid, new method

1974 ◽  
Vol 336 (1606) ◽  
pp. 393-406 ◽  
Keyword(s):  
Experimental Data ◽  
Diffusion Coefficient ◽  
Laminar Flow ◽  
Diffusion Coefficients ◽  
Entire Range ◽  
Liquid Mixtures ◽  
Mutual Diffusion ◽  
Mutual Diffusion Coefficient ◽  
Mechanical Theory ◽  
Statistical Mechanical

Mutual diffusion coefficients for liquid mixtures of ethanol and water have been measured over the entire range of composition and for temperatures from 25 to 65 °C at a pressure of 1 bar (10 5 Pa). At the lowest temperature, the results establish the validity of a new experimental method based upon Taylor’s analysis of solute dispersion in laminar flow. The method offers advantages of simplicity and speed over other techniques, and allows direct measurement of diffusion coefficients at well-defined mixture compositions. The experimental data have an estimated uncertainty of ±2.5% . The results have been utilized to evaluate friction coefficients arising in the statistical mechanical theory of transport in liquid mixtures.

scholarly journals Dependence of Viscosity and Diffusion on β-Cyclodextrin and Chloroquine Diphosphate Interactions

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1433
Author(s):  
Lenka Musilová ◽  
Aleš Mráček ◽  
Eduarda F. G. Azevedo ◽  
M. Melia Rodrigo ◽  
Artur J. M. Valente ◽  
...  
Keyword(s):  
Diffusion Coefficient ◽  
Diffusion Coefficients ◽  
Mutual Diffusion ◽  
Binary Diffusion Coefficient ◽  
Concentration Gradients ◽  
Cross Diffusion ◽  
Taylor Dispersion Technique ◽  
Dispersion Technique ◽  
And Diffusion ◽  
Chloroquine Diphosphate

Mutual diffusion coefficients of chloroquine diphosphate (CDP) in aqueous solutions both without and with β-cyclodextrin (β-CD) were measured at concentrations from (0.0000 to 0.0100) mol dm−3 and 298.15 K, using the Taylor dispersion technique. Ternary mutual diffusion coefficients (Dik) measured by the same technique are reported for aqueous CDP + β-CD solutions at 298.15 K. The presence of β CD led to relevant changes in the diffusion process, as showed by nonzero values of the cross-diffusion coefficients, D12 and D21. β-CD concentration gradients produced significant co-current coupled flows of CDP. In addition, the effects of β-CD on the transport of CDP are assessed by comparing the binary diffusion coefficient of aqueous CDP solutions with the main diffusion coefficient (D11) measured for ternary {CDP(1) + β-CD(2)} solutions. These observations are supported by viscosity analysis. All data allow to have a better interpretation on the effect of cyclodextrin on the transport behavior of CDP.

Molecular dynamics study of diffusion of krypton in water at different temperatures

2016 ◽  
Vol 30 (11) ◽  
pp. 1650064 ◽  
Author(s):  
Dipendra Bhandari ◽  
N. P. Adhikari
Keyword(s):  
Molecular Dynamics ◽  
Diffusion Coefficient ◽  
Diffusion Coefficients ◽  
Mean Square Displacement ◽  
Mutual Diffusion ◽  
Arrhenius Behavior ◽  
Self Diffusion ◽  
Velocity Autocorrelation ◽  
Different Temperatures ◽  
Self Diffusion Coefficient

Molecular dynamics study of diffusion of two krypton atoms in 300 SPC/E water molecules at temperatures 293, 303, 313, 323 and 333 K has been carried out. Self-diffusion coefficient of krypton and water along with their mutual diffusion coefficients are estimated. Self-diffusion coefficient for krypton is calculated by using Mean Square Displacement (MSD) method and Velocity Autocorrelation (VACF) method, while that for water is calculated by using MSD method only. The mutual diffusion coefficient is estimated by using the Darken’s relation. The diffusion coefficients are found to follow the Arrhenius behavior. The structural properties of the system have been estimated by the study of solute–solute, solvent–solvent, and solute–solvent Radial Distribution Function (RDF).

scholarly journals Effect of Modification on the Fluid Diffusion Coefficient in Silica Nanochannels

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4030
Author(s):  
Gengbiao Chen ◽  
Zhiwen Liu
Keyword(s):  
Diffusion Coefficient ◽  
Diffusion Coefficients ◽  
Surface Effect ◽  
Bulk Water ◽  
Self Diffusion ◽  
Average Diffusion Coefficient ◽  
Average Diffusion ◽  
Chain Lengths ◽  
Fluid Diffusion ◽  
Self Diffusion Coefficient

The diffusion behavior of fluid water in nanochannels with hydroxylation of silica gel and silanization of different modified chain lengths was simulated by the equilibrium molecular dynamics method. The diffusion coefficient of fluid water was calculated by the Einstein method and the Green–Kubo method, so as to analyze the change rule between the modification degree of nanochannels and the diffusion coefficient of fluid water. The results showed that the diffusion coefficient of fluid water increased with the length of the modified chain. The average diffusion coefficient of fluid water in the hydroxylated nanochannels was 8.01% of the bulk water diffusion coefficient, and the diffusion coefficients of fluid water in the –(CH2)3CH3, –(CH2)7CH3, and –(CH2)11CH3 nanochannels were 44.10%, 49.72%, and 53.80% of the diffusion coefficients of bulk water, respectively. In the above four wall characteristic models, the diffusion coefficients in the z direction were smaller than those in the other directions. However, with an increase in the silylation degree, the increased self-diffusion coefficient due to the surface effect could basically offset the decreased self-diffusion coefficient owing to the scale effect. In the four nanochannels, when the local diffusion coefficient of fluid water was in the range of 8 Å close to the wall, Dz was greater than Dxy, and beyond the range of 8 Å of the wall, the Dz was smaller than Dxy.

scholarly journals Time-Dependent Diffusion Coefficients for Chaotic Advection due to Fluctuations of Convective Rolls

Fluids ◽  
2018 ◽  
Vol 3 (4) ◽  
pp. 99 ◽  
Author(s):  
Kazuma Yamanaka ◽  
Takayuki Narumi ◽  
Megumi Hashiguchi ◽  
Hirotaka Okabe ◽  
Kazuhiro Hara ◽  
...  
Keyword(s):  
Diffusion Coefficient ◽  
Liquid Crystals ◽  
Diffusion Coefficients ◽  
Coarse Graining ◽  
Chaotic Advection ◽  
Time Dependent ◽  
Local Order ◽  
Weak Turbulence ◽  
Normal Diffusion ◽  
Convective Rolls

The properties of chaotic advection arising from defect turbulence, that is, weak turbulence in the electroconvection of nematic liquid crystals, were experimentally investigated. Defect turbulence is a phenomenon in which fluctuations of convective rolls arise and are globally disturbed while maintaining convective rolls locally. The time-dependent diffusion coefficient, as measured from the motion of a tagged particle driven by the turbulence, was used to clarify the dependence of the type of diffusion on coarse-graining time. The results showed that, as coarse-graining time increases, the type of diffusion changes from superdiffusion → subdiffusion → normal diffusion. The change in diffusive properties over the observed timescale reflects the coexistence of local order and global disorder in the defect turbulence.

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