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9-39

diffusion coefficient

URNurn:iso:std:iso:80000:-9:ed-2:en:item:9-39

https://metanorma.github.io/isq-smart/quantities/part-9/t9-39
urn:iso:std:iso:80000:-9:ed-2:en:item:9-39

ISQ Identifiers

ISO

urn:iso:std:iso:80000:-9:ed-2:en:item:9-39

IEC

urn:iec:std:iec:80000-9:2019:::item:9-39

Designations

ENdiffusion coefficient

FRcoefficient de diffusion

Symbol

D

Notation systems

Rendered

D

AsciiMath

D

LaTeX

D

Definition

proportionality coefficient of local molecular concentration $C_{B}$ (molecular concentration) of substance $B$ in the mixture multiplied by the local average velocity (ISO 80000-3: Space and time) $v_{B}$ of the molecules of $B$ , and minus the gradient of the local molecular concentration $C_{B}$ (molecular concentration) of substance $B$ in the mixture, expressed by:

C_{B} 〈 v_{B} 〉 = - D grad C_{B}

coefficient de proportionnalité entre le produit de la concentration moléculaire $C_{B}$ (molecular concentration) locale du constituant $B$ dans le mélange par la vitesse moyenne locale (ISO 80000-3: Space and time) $v_{B}$ des molécules du constituant $B$ , et l'opposé du gradient de la concentration moléculaire $C_{B}$ (molecular concentration) locale du constituant $B$ dans le mélange, exprimé par:

C_{B} 〈 v_{B} 〉 = - D grad C_{B}

Units

m^{2} \cdot s^{- 1}

square metre per second

View related quantities →

Referenced by

thermal diffusion coefficient

Concept HierarchyPendrill (2024)

L² T⁻¹L² T⁻¹ quantitiesLevel 0 · Kind

Broader concepts

◇ L² T⁻¹ quantities

Characterizes

● molecule● substance

Ontology
isq:Quantity smart:TermEntry

Class Hierarchy

smart:Entity smart:TermEntryisq:Quantity

A physical quantity as defined in ISO/IEC 80000, with associated symbols, definitions, and units of measurement.

Instance IRI

isq:t9-39

Properties

isq:QuantityShape

Property	Value
rdf:type	isq:Quantity smart:TermEntry
dcterms:identifier	9-39
skosxl:prefLabel	"diffusion coefficient <chemistry>"@en
skosxl:altLabel	"D"@en
skos:definition	proportionality coefficient of local molecular concentration stem:[C_"B"] (<<t9-9.2>>) of substance stem:["B"] in the mi…
isq:hasUnit	m^2*s^(-1) (square metre per second)
isq:hasDimension	isq:Dimension
smart:hasBindingnessType	bindingness-type:normative
dcterms:isPartOf	isq:part-9

Related Entities

isq:QuantityShape isq:part-9 isq:Unit isq:Dimension isq:hasDimension smart:TermEntry