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Fiche 1,  Justifications,  Anglais

Record number: 1, Textual support number: 1 DEF

[A factor] represented by a term in the van Deemter equation. It is the contribution to plate height that is due to molecules traveling along paths through the column and it depends on the particle size and geometry of the packing.  2, fiche 1, Anglais, - eddy%20diffusion%20term

Record number: 1, Textual support number: 1 CONT

Eddy diffusion broadens the band when passing through the column and detected in the chromatography. This is due to the molecules of the sample traveling through the column along many different paths of different lengths. The shortest path is the front of the band and the longest path is located in the back of the band. This can be corrected if the band is broad and the column support is of small size and uniform. This effect may be described by the van Deemter equation . H=A+(B/u)+Cu. Where M is the flow rate, A is the eddy diffusion term, B/u is the longitudinal diffusion term and Cu is the mass-transfer rate term. The eddy diffusion is independent of the flow-rate and only is concerned by how the column was packed.  1, fiche 1, Anglais, - eddy%20diffusion%20term

Fiche 1,  Justifications,  Français

Fiche 1,  Justifications,  Espagnol

Fiche 2,  Justifications,  Anglais

Record number: 2, Textual support number: 1 DEF

Irregularity in the diffusion of solute molecules that occurs in a porous chromatographic support, by the rapid process of mixing of the swirling eddies of the fluid. The phenomenon is due to the fact that (a) the pathlength for some solute molecules is either shorter or longer than that for the bulk of the molecules; and (b) the rate of solvent flow varies in different regions of the porous support.  2, fiche 2, Anglais, - Eddy%20diffusion

Record number: 2, Textual support number: 1 CONT

Non-ideal flow occurs when different elements of substrate move through the reactor at varying rates such that they are in contact with the enzyme for variable periods owing to their differing residence times in the reactor giving an opportunity for different extents of reaction to take place and for further reaction of the desired product and side-reactions to take place. Non-ideal flow can be caused by factors such as back-mixing, channelling, or the presence of stagnant flow regions within the reactors.... Eddy diffusion also causes inhomogeneous distribution of fluid. This effect occurs when there are variations in the size and shape of the support particles and because of the tendency of the larger particles to become packed close to the walls of the column such that the flow rate varies over the cross-section of the column.  3, fiche 2, Anglais, - Eddy%20diffusion

Fiche 2,  Justifications,  Français

Record number: 2, Textual support number: 1 CONT

Les utilisations délibérées les plus anciennes et les plus courantes de la turbulence concernent l'intensification des transferts de chaleur et de matière au sein des fluides ou vers les parois qui les limitent. Dans le second cas, l'effet de la diffusion moléculaire à proximité immédiate de la paroi est déterminant, car la diffusion turbulente y tend vers zéro dans les sous-couches visqueuses sur parois lisses, ou y intervient par des forces de pression à petite échelle sans action sur le transfert de contaminants scalaires sur parois rugueuses.  1, fiche 2, Français, - diffusion%20turbulente

Fiche 2,  Justifications,  Espagnol

Fiche 3,  Justifications,  Anglais

Record number: 3, Textual support number: 1 DEF

Diffusion which occurs in turbulent flow, by the rapid process of mixing of the swirling eddies of fluid.  3, fiche 3, Anglais, - eddy%20diffusion

Record number: 3, Textual support number: 1 OBS

eddy: A vortexlike motion of a fluid running contrary to the main current.  3, fiche 3, Anglais, - eddy%20diffusion

Fiche 3,  Justifications,  Français

Record number: 3, Textual support number: 1 DEF

Diffusion de matière ou des propriétés de particules d'air, telles que la chaleur et la quantité de mouvement, par les tourbillons d'un flux turbulent.  2, fiche 3, Français, - diffusion%20turbulente

Fiche 3,  Justifications,  Espagnol

Record number: 3, Textual support number: 1 DEF

Difusión de materia o de las propiedades de partículas de aire, como el calor y la cantidad de movimiento, por los remolinos de un flujo turbulento.  3, fiche 3, Espagnol, - difusi%C3%B3n%20turbulenta