Nucleation rate constant

The nucleation rate constant (Eq. (5.8.5)) k depends on the size of the critical crystallization nucleus according to the Volmer-Weber equation... 

Expressing the specific homogeneous nucleation rate constant, kh, according to (2) and substituting equation (1-4) into equation (II-6), (II-6) can finally yield a general expression for the particle nucleation rate, fit), (12,58, 9). 

Chronoamperometric experiments on zinc electroreduction on GC from acetate solutions showed that the nucleation density increases with increase of temperature [44]. M oreover, the nucleation rate constant is always very large, equal to 1.41 x 10 s . This indicates that the mechanism of zinc electrodeposition on the GC electrode follows a three-dimensional instantaneous nucleation and growth model within the controlled temperature range. 

The same mechanism of zinc electrodeposition on the GC electrode was observed in sulfate, chloride, and acetate ion solutions [227]. The anions mainly affected the nucleation densities during zinc deposition, which resulted in a different surface morphology. The nucleation rate constant was the same in the chloride and sulfate solutions and was equal to 1.22 x 10 s h In the presence of acetate and chloride ions, the deposited zinc film tends to grow in a multilayered pattern, while in sulfate solution, the zinc deposition forms irregular grains. A new approach to the estimation of zinc electrocrystallization parameters on the GC electrode from acetate solutions was described by Yu et al. [228]. 

Bertram, A. K., and J. J. Sloan, Temperature-Dependent Nucleation Rate Constants and Freezing Behavior of Submicron Nitric Acid Dihydrate Aerosol Particles under Stratospheric Conditions, J. Geophys. Res., 103, 3553-356f (f998a). 

These equations give the general solution to the problem of multistep nucleation when the rate constants are all different at the start, but after the nucleus contains more than r atoms, the nucleation rate constants have a constant value k for the addition of successive atoms of product- The limit for short times may be obtained by induction as before, and they obtain... 

The data in Table 5.19 showed that B-Si-ZSM-5 has a remarkable nucleation rate constant which might be caused by the similarity of the properties of B and Si. Along with a decrease in the ionic radii of subgroup elements M(III), the nucleation rate... 

Zeolite M (M-Si-ZSM-5) Nucleation rate constant kf Crystal growth-rate constant K Gel-dissolving rate constant k4 Si02/M20 (mol/mol)... 

Overall growth rate constant Nucleation rate constant Crystal size Initial crystal size Final crystal size Nucleus size... 

Nucleation rate constant OHad formation and backreaction rate constants Thickness of CCL Catalyst content of CCL in mg cm (geometric area)... 

In equation XII, B, is the rate of nucleation KN, the nucleation rate constant and b, the order of the process, which usually is between 2 and 5. 

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