Diffusion versus

Thus, a plot of the apparent diffusivity versus the linear adsorption equilibrium constant should be linear so long as Dp and D,i remain constant. 

In order to design such an efficient and effective device, one must understand the mechanisms by which drug is transported in the ocular interior. One issue debated in the literature for some time has been the relative importance of transport by passive diffusion versus that facilitated by the flow of fluid in the vitreous (see, e.g., Ref. 226). To predict the geometric distribution even at steady state of drug released from an implant or an intravitreal injection, one must appreciate which of these mechanisms is at work or, as appropriate, their relative balance. 

Figure 7.37 Log aqueous diffusivities versus log molecular weights.

Figure 9 Properties of the attractive colloidal fluid investigated in Ref. 75 (a) self-diffusivity and (b) average free volume versus strength of the interparticle attraction (c) self-diffusivity versus average free volume for the hard-sphere fluid (open circles) and the attractive colloidal fluid (closed circles). Data compiled from Ref. 75.

Fig. 10.2 Diffusive versus ballistic transport of electrons (See Color Plates)...

Burning of Small Particles - Diffusion versus Kinetic Limits... 

Volume diffusion versus grain-boundary diffusion... 

Viability of Starch Derivatives as Flavoring Encapsulants. The capillary GC vapor phase flux term (defined by a percent external standard or ZEStD flux) previously described (34) was used to screen starch derivatives (oxidized, dextrinized and/or covalent amino acid linkage) as to their flavor encapsulation potential. The samples were prepared as previously described (34) with the exception of an added reduced pressure deaeration step, thus allowing the use of the headspace diffusivity versus retention standard curves to predict volatile lemon oil retention following spray drying. 

Fig. 6. Reciprocal diffusivity versus concentration in dilute solutions of linear polystyrenes in CC14> for three polymer molecular weights (indicated) (after Ref.4 >, with permission).

In a similar way the Damkohler Number (Eq. 22-1 lb) measures the relative pace of diffusion versus advection in the time period tT = k which corresponds to the mean life of the reactive chemical. In fact ... 

The single-potential-step chronoamperometric technique was selected here for the study of diffusion versus kinetic control for the formation of benzonitrile. 

Design Principles [Diffusion versus Erosion (Surface versus Bulk)] 280... 

Fig. 27. Thermal diffusivity versus temperature of [Iss with different Y2O3/AI2O3 ratio from 6/0 to 0/6 (mol/mol) [371] and ass (n = 1.4, m = 1) [379]...

Katz, M.M., Hargens, A.R. and Garfin, S.R. (1986) Intervertebral disc nutrition Diffusion versus convection. Clin Orthop, 243-245... 

Fig. 5.5. Luminescence quenching (bullets, right hand, axis) and short-circuit current Ac (black squares, left hand axis) vs. molar fullerene concentration in a bulk hetero junction composite. The different onsets for percolation for the two phenomena (exciton diffusion versus ambipolar carrier transport) can be clearly seen...

Figure 4. Effective diffusivity versus initial coke content when r =l (legends in fig. 1)...

The Biot number Bim for mass transport. This can be interpreted as the ratio of internal to external transport resistance (intraparticle diffusion versus interphase diffusion) ... 

FIG. 18.2 Activation energy of diffusion versus mean square collision diameter. 

The diffusion of carbon in transition metal carbides proceeds via a vacancy mechanism and thus the diffiisivity increases with increasing vacancy concentration in the nonmetal sublattice. However, carbon diffusivities versus composition were measured only for very few types of... 

Crowley J. L. and Ghent E. D. (1999) An electron microprobe study of the U-Th-Pb systematics of metamorphosed monazite the role of Pb diffusion versus overgrowth and recrystallization. Chem. Geol. 157, 285-302. 

It is often useful to non-dimensionalize a differential equation, not only because the resulting equation is generally both simpler in form and more general in its applicability, but also because it provides a convenient way of comparing the relative importance of terms in the equation (e.g., the importance of diffusive versus advective flux). Two important non-dimensional parameters which appear in the conservation of solute mass equation are the Peclet number and the Damkohler number. The Peclet number is given by... 

Spiral wave dynamics Reaction and diffusion versus... 

---