The phrase "a couple of diffusion" is not correct in written English.
It is typically used to refer to a small number of instances or types of diffusion, but the noun "diffusion" is uncountable in this context.
Example: "We observed a couple of diffusion processes in the experiment."
Alternatives: "a few instances of diffusion" or "several types of diffusion".
These results support the view that two-stage sorption results from a coupling of diffusion to high-frequency viscoelastic modes, which are insensitive to polymer molecular weight.
In the molten state, lasting a couple of microseconds, rapid diffusion of Si into Ti occurs leading to formation of new phases during rapid solidification of the molten surface layer.
When 0.45 < n < 0.89, anomalous transport is observed which is driven by a coupling of Fickian diffusion and polymer relaxation/degradation, and the release is dominated by non-Fickian diffusion [ 30]. Figure 2 shows the FTIR spectra [ 31, 32] of KPAsp, KPAsp/PVA semi-IPN, and KPAsp/PVA IPN hydrogels, respectively.
The Korsmeyer-Peppas model indicated a good linearity (r = 0.9956) and the value of release exponent n which is 0.7246 indicates anomalous nonfickian transport drug release, which appeared to indicate a coupling of the diffusion and polymer relaxation mechanisms.
The nanoparticles revealed Higuchi release pattern and release occurred by coupling of diffusion and erosion.
It is shown that both may also occur in ternary systems with coupling of diffusion and reaction.
For the coupling of diffusion from the head to the neck, we need to scale the diffusion coefficient with the ratio of their cross sectional areas.
Their work is mainly motivated by the work of Brand et al. [12] who studied the Hopf-bifurcation problem and its exchange of stability for a coupled reaction diffusion model in (mathbf{R}^{a}).
The obtained diffusion coefficient showed a maximum in the vicinity of a voltammetric current peak; this corresponded with the potential dependence of a coupled diffusion coefficient expected in the extreme case of electron-transport control.
In spite of its empirical shortcomings, the correlation provides a universal understanding of the dispersion behaviors in open channels and random particle packs and a new understanding of the coupling behavior of diffusion and convection in particle packs.
