List of Symbols.pdf - Eawag-Empa Library

LIST OF SYMBOLS

A - atom

A - radioactive source activity

A - experimental constant

A - radiative transition probability

a - geometric constant

a - probability ratio for two processes

aa - analytical property **of** a

b - optical path length

B - atom

B - constant

bc - background current

bci - ionization background current

C - carrier gas

C - instantaneous concentration

co - initial concentration

pin

- minimum instantaneous concentration

CmaX - maximum instantaneous concentration

c' - instantaneous concentration in the effective volume **of** the detector

C, - heat capacity at constant pressure

Cy - heat capacity at constant volume

D - diffusion coefficient

e - secondary electron, slow electron

E - voltage

EP - excitation potential

E, - excitation energy **of** the eluted substance

F - Faraday constant

G - mass

H - height equivalent to a theoretical plate

I - current

I - atom or molecule **of** impurity

ic - ionization current

ic, - ionization current **of** alkali metal

i ~ - ionization ~ ~ current . ~ **of** ~ de-excited atomic states

ic,,, - ionization current due to electron capture

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ic,,,

icHe

ic, - ionization current **of** carbonaceous substances due to the FID mechanism

I,

1,

- ionization current **of** impurities in the carrier gas

- ionization current **of** the carrier gas due to direct ionization

- intensity **of** emitted light

- intensity **of** fluorescence emitted light

Z: ZP - ionization potential

J - Joule's constant

- initial intensity **of** emitted light

k - constant

k1,2,3 ,,,. - rate constant **of** reaction 1, 2, 3, . . .

kd.i - rate constant **of** dissociation, ionization

k, - statistical constant dependent on the number **of** measurements, n

K - absolute temperature, Kelvin

K - thermal conductivity

Ka,b - dissociation constant **of** acid, base

1 - electron free path

1 - length **of** heated filament

I - detector linearity

L - column length

M - atom

M - molecular weight

M" - metastable atomic state

M* - excited atomic state

n - number **of** electrons

n - number **of** theoretical plates

n - number **of** measurements

N - number **of** moles

N' - number **of** moles in the effective volume **of** the detector

ORG - polyatomic molecule **of** organic compound

CI(0RG) - chlorine-containing ployatomic organic molecule

p - pressure

pc,s - partial pressures **of** the carrier gas, the eluted substance

ppb - part per billion (American billion = lo9)

Q - electric charge

Q - conductivity cell constant

Q - amount **of** heat

QE - cross-section for electron capture ionization

Qc,s - cross-section **of** direct ionization **of** carrier gas, eluted substance

r - column radius

r - radius **of** the sensor

R - universal gas constant

R - amplifier resistance

- heated filament resistance

- detector response to property a

- estimated standard deviation

- eluted substance

- signal **of** analytical probcrty a, **of** eluted substance S

- time

- the Student distribution

- time **of** the beginning and the end **of** elution

- time corresponding to the inflection points **of** the elution curve

- elution time

- elution curve width

- time **of** passage **of** gas through the effective volume **of** the detector

- temperature

- temperature **of** the detector walls

- temperature **of** the heated filament

- linear flow-rate **of** gas

- volume flow-rate **of** gas

- flow-rate expressed in moles

- mean molecular velocity

- velocity **of** electrons

v1 ,2.3. ._. - rate **of** reaction 1 , 2, 3, . . .

I/ - volume

I/, - effective volume **of** detector

X - molar fraction

Z - constant

Zi - ionic charge

Z - the third particle in a three-body collision

z,, za - number **of** non-elastic collisions

a - recombination coefficient

c! - temperature coefficient

c1 - degree **of** dissociation

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r

- thermistor material constance

- selectivity

A - change in parameter

q,, - photoionization efficiency

1"

- mean free path, mobility

e - density

T - time constant

@ - fluorescence yield

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