Diffusion Coefficient Units & Equation 3:36 3:55 Next Lesson Bulk Density Definition, Formula & Calculation Fluid Friction | Definition, Types & Example 5:51 Internal Friction | Overview & Angle Specific Volume Definition, Formulas & Units 6:17 Precipitation Hardening | Definition, Process...
Kagan, G.; Li, W.; Hopson, R.; Williard, P. G. Internally referenced diffusion coefficient-formula weight (D-FW) analysis of 31P diffusion-ordered NMR spectroscopy (DOSY). Org. Lett. 2009, 11, 4818-4821. Jones, D. T.; Cozzetto, D. DISOPRED3: precise disordered region predictions ...
during a certain time interval (t) in a medium whose coefficient of diffusion (D) is known,Dbeing equal to one-half the average of the square of thedisplacementin thex-direction. This formula for probability “density” allowsPto be plotted againstx. The graph is the familiarbell-shaped ...
Ideally, bicrystal samples should be used to directly measure interface diffusivities; a diffusant is deposited on a bicrystal surface, the sample is annealed, and the composition profile is measured, leading to the determination of the interface diffusion coefficient. Only a very small set of mea...
Glycerol, with a reflection coefficient of about 0.5 presents the greatest danger that if used for extended medical hyperosmotic treatment it would cross the BBB and begin holding water within the brain [JOURNAL OF NEUROLOGICAL SCIENCES; Ziai,WC; 261(1-2):157-166 (2007)]. Concentrations of ...
D = diffusion coefficient [m2/s] dφ = change in concentration of substance [mass or mol/m3] dx = change in length [m] For simple one-dimensional transport,the diffusion coefficient describes the time–rate of change of concentration. The diffusion coefficient varies from substance to substance...
The governing equation (1) becomes a heat equation if the advection speed \(\beta\) is zero with a positive diffusion coefficient. Also \(\psi _1(x)\), \(\phi _{1}(t)\) and \(\phi _{2}(t)\) are the known smooth functions. In the past, various authors have studied ...
Theb-valueis a factor that reflects the strength and timing of the gradients used to generate diffusion-weighted images. The higher theb-value, the stronger the diffusion effects. Specifically, ifSois the MR signal at baseline andDis the diffusion coefficient, the signal (S) after the diffusio...
In the case when\({D}_{1,\,{z}_{{i}_{1}}}\)is uncorrelated with\({z}_{{i}_{2}}\)and\({D}_{1,\,{z}_{{i}_{2}}}\)uncorrelated with\({z}_{{i}_{1}}\), then the growth of the variance only depends on the diffusion coefficient. ...
a homogeneously distributed and random trap field (see Supplementary Note3). In addition, we developed a coarse-grained theoretical model based on continuum diffusion of the exciton concentration (see Supplementary Note4). The continuum theory predicts an exponential decay of the diffusion coefficient,...