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7 Appendix: Quantity- / Unit Symbols and Important Constants

Name of Quantity

Symbol

Domain / Value

Unit

Unitsymbol

Electrical charge

q, Q

Coulomb

C

Boltzmann constant

kb

1.3811023

Joule/Kelvin

J/K

Universal gas constant

R

8.314

Joule

KelvinMol

J/(Kmol)

Faraday constant

F

9.64104

Coulomb

Mol

C/mol

Electrical resistance

R

Ohm

Specific resistance

r

Ohmmeter

m

Electrical conductivity

σ

Siemens

S

Electrical capacitance

C

Farad

F

Electrical current

i, I

Ampere

A

Electrical potential

u, U

Volt

V

Charge number

z

Membrane potential

Urev

Volt

V

Time constant

τ

second

s

Time

t

second

s

Nabla operator

1/meter

m1

Electrical field intensity

vector

E

Volt

meter

V/m

Electrical permeability

ϵ

Amperesecond

Voltm

As/Vm

Vacuum electrical per-

meability

ϵ0

8.8531012

Amperesecond

Voltm

As/Vm

Magnetic field intensity

vector

H

Ampere

meter

A/m

Magnetic permeability

μ

Voltsecond

Amperem

Vs/Am

Vacuum magnetic per-

meability

μ0

4π107

Voltsecond

Amperem

Vs/Am

Current density vector

J

Ampere

meter2

A/m2

Current density vector of

electrical field

JE

Ampere

meter2

A/m2

Current density vector of

ion membrane currents

Ji

Ampere

meter2

A/m2

Arbitrary vector field

A

undefined

undefined

Arbitrary scalare function

ϕ

undefined

undefined

Volume charge density

ρv

Ampere

meter3

As/m3

Specific electrical con-

ductivity

κ

Siemens

meter

S/m

Angular frequency

ω

Hertz

Hz

Distance between current

source and measuring

location

r

meter

m