Evaluation of surface tension and Tolman length as a function of droplet radius from experimental nucleation rate and supersaturation ratio: Metal vapor homogeneous nucleation

2006 ◽  
Vol 124 (1) ◽  
pp. 014506 ◽  
Author(s):  
A. A. Onischuk ◽  
P. A. Purtov ◽  
A. M. Baklanov ◽  
V. V. Karasev ◽  
S. V. Vosel
Keyword(s):  
Surface Tension ◽  
Nucleation Rate ◽  
Homogeneous Nucleation ◽  
Metal Vapor ◽  
Droplet Radius ◽  
Supersaturation Ratio ◽  
Tolman Length

scholarly journals Eliminating the Pre-exponential Factor in Classical Nucleation Theory

2019 ◽  
pp. 1-6
Author(s):  
John H. Jennings
Keyword(s):  
Molecular Weight ◽  
Surface Tension ◽  
Nucleation Rate ◽  
Homogeneous Nucleation ◽  
Polymer Concentration ◽  
Nucleation Theory ◽  
Classical Nucleation Theory ◽  
Low Molecular Weight ◽  
Exponential Factor ◽  
New Equation

Blander and Katz give a formula in classical nucleation theory, J = A exp K, for homogeneous nucleation (liquid-->gas). Jennings proved that dlnA/dK = 1/6K for all pure liquids by combining two theories, taking the limit as polymer concentration-->0. This gives lnA = (1/12)ln(K2) + C, where C is the integration constant. The conjecture is that C is a constant for fluids of low molecular weight.  We used data for 7 sample solvents, and solved for C. The surface tension drops out in C, which makes C more accurate, as the surface tension is difficult to get at 0.89Tc, the limit of superheat. Tc = critical point in Kelvin. All quantities are evaluated at the limit of superheat, which is approximately 0.89Tc for solvents. C = 74.77 ± 0.33 for the 7 solvents (not all alkanes). This eliminates the prefactor A, streamlining J: ln J = (1/12)ln(K2) + 74.77 + K is the exact new equation.  A computer can more easily be used to calculate J, the nucleation rate.

Surface tension of sulfur nanoparticles as determined from homogeneous nucleation experiments

2016 ◽  
Vol 97 ◽  
pp. 1-21 ◽  
Author(s):  
A.A. Onischuk ◽  
S.V. Valiulin ◽  
S.V. Vosel ◽  
V.V. Karasev ◽  
V.D. Zelik ◽  
...  
Keyword(s):  
Surface Tension ◽  
Homogeneous Nucleation ◽  
Sulfur Nanoparticles

Mean Lifetime of an Embryo in the Homogeneous Nucleation from Solution of the Tetracyanoplatinates(II) of Barium, Calcium, and Magnesium

1973 ◽  
Vol 51 (20) ◽  
pp. 3435-3442 ◽  
Author(s):  
O. A. Bempah ◽  
O. E. Hileman Jr.
Keyword(s):  
Homogeneous Nucleation ◽  
Silicone Oil ◽  
Classical Model ◽  
Selective Extraction ◽  
Supersaturation Ratio ◽  
Mean Lifetime ◽  
High Supersaturation ◽  
The Mean ◽  
Calcium And Magnesium ◽  
Oil Crystallization

The mean lifetime of an embryo in the homogeneous nucleation from aqueous solution of the tetracyanoplatinates(II) of barium, calcium, and magnesium has been studied using the droplet technique. Supersaturation in the droplets was generated by selective extraction of the solvent into the surrounding silicone oil. Crystallization in the droplets was followed by photomicrography using plane polarized light.The data were analyzed using both the classical model and the mean lifetime model of Carlier and Frisch. The experimental results are consistent with the predicted relationship between the logarithm of the nucleation rate or the logarithm of the mean lifetime of an embryo and the inverse of the square of the logarithm of the supersaturation ratio at high supersaturation ratios. The calculated values of the inter-facial energy, using both models, are in close enough agreement to justify the assumptions made in the analysis.

Crystal Nucleation in Submicron Droplets of Pure Elements

1993 ◽  
Vol 321 ◽  
Author(s):  
Louis M. Holzman ◽  
Thomas F. Kelly ◽  
W. N. G. Hitchon
Keyword(s):  
Heterogeneous Nucleation ◽  
Homogeneous Nucleation ◽  
Crystal Nucleation ◽  
Droplet Radius ◽  
Electrohydrodynamic Atomization ◽  
Submicron Droplets ◽  
Diffraction Patterns

ABSTRACTLiquid-to-crystal nucleation has been studied extensively through droplet experiments to locate examples of homogeneous nucleation. However, prior to this work very few examples have been found, which implies that the experiments have not been able to isolate heterogeneous nucleants in a small percentage of the droplets as is required. In this research, electrohydrodynamic atomization (EHD) is used to produce sub-Micron droplets of pure elements that are largely free of heterogeneous nucleants.Diffraction patterns of individual EHD-produced droplets are viewed to determine the fraction of crystalline droplets produced as a function of droplet radius. These results are compared to theories for surface and volume heterogeneous nucleation and for homophase nucleation. It is found that Si and Ge nucleate through either homogeneous nucleation or nucleation by homophase impurities. Nucleation results for vanadium and iron were not conclusive.

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