TERMIUM Plus^®

Fiche 1,  Justifications,  Anglais

Record number: 1, Textual support number: 1 CONT

... we have neglected the energy loss term which is unimportant in low-density environments. [The] equation can be solved in an approximate way by reminding that [the] region ... is characterized by the condition [where] the diffusion term dominates over the advection one.  2, fiche 1, Anglais, - diffusion%20term

Fiche 1,  Justifications,  Français

Record number: 1, Textual support number: 1 CONT

Il est aussi justifiable […] de négliger le terme de diffusion thermique pour les régimes de haut Rayleigh, le phénomène de diffusion étant négligeable devant l'advection pour transporter la chaleur dans le fluide.  1, fiche 1, Français, - terme%20de%20diffusion

Fiche 1,  Justifications,  Espagnol

Fiche 2,  Justifications,  Anglais

Record number: 2, 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 2, Anglais, - eddy%20diffusion%20term

Record number: 2, 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 2, Anglais, - eddy%20diffusion%20term

Fiche 2,  Justifications,  Français

Fiche 2,  Justifications,  Espagnol

Fiche 3,  Justifications,  Anglais

Record number: 3, Textual support number: 1 CONT

Passive or long-term diffusion involves mainly fine particles separated from the jet during descent due to turbulence at the interface of the jet and the water column. This fraction, composed of fine particles entrained by currents, is a problem when dealing with contaminated sediment, because contaminants are bound mainly to fine particles.  2, fiche 3, Anglais, - passive%20diffusion

Fiche 3,  Justifications,  Français

Record number: 3, Textual support number: 1 CONT

La diffusion passive ou à long terme, implique surtout des particules fines qui, lors de la descente, se séparent du jet sous l'action de la turbulence à l'interface de celui-ci avec la colonne d'eau. Cette fraction, constituée de particules fines entraînées sous l'action des courants, est problématique lorsqu'il s'agit du rejet en eaux libres de sédiments contaminés, car les contaminants sont surtout liés aux particules fines.  2, fiche 3, Français, - diffusion%20passive

Fiche 3,  Justifications,  Espagnol

Fiche 4,  Justifications,  Anglais

Record number: 4, Textual support number: 1 DEF

... B-term (second term) of the van Deemter equation.  1, fiche 4, Anglais, - molecular%20diffusion%20term

Record number: 4, Textual support number: 1 OBS

Imponant in band broadening only at very low flow rates below the minimum plate height where the diffusion of individual solutes can occur in a longitudinal (lengthwise) direction on the column.  1, fiche 4, Anglais, - molecular%20diffusion%20term

Fiche 4,  Justifications,  Français

Fiche 4,  Justifications,  Espagnol

Fiche 5,  Justifications,  Anglais

Fiche 5,  Justifications,  Français

Record number: 5, Textual support number: 1 OBS

Référence pour l'anglais et le français : "A Matter of Resolution/Une question de résolution", CMC Information, Vol II, No 1.  1, fiche 5, Français, - terme%20de%20diffusion%20horizontale

Fiche 5,  Justifications,  Espagnol