INFICON Composer Gas Concentration Controller - Manual (Page 45)

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IP
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9L
Composer Operating Manual
Combining 12, 13 and 14:
[15]
Simplifying leads to,
[16]
where,
[17]
[18]
[19]
Since the equation is obviously a quadratic, the solutions are of the following
form.
[20]
Since x1,2 represents the Mole Fraction of the gasses, acceptable solutions
are,
[21]
The general result of this analysis is that the technique is most sensitive to
composition changes when the Molecular Weight difference between the
carrier gas and the Precursor is the greatest.
λ 1 m 1 – ( )x + { }
g h – ( ) 1 h – ( ) [ ]
x 1 g – ( ) g h – ( ) + [ ]
------------------------------------------------ h + =
Ax
2
Bx C + + 0 =
A λ m 1 – ( ) 1 g – ( ) =
B λm g h – ( ) λ 1 2g – h + ( ) h 1 g – ( ) – + =
C λ 1 – ( ) g h – ( ) =
x
1,2
B – B
2
4AC – ±
2A
------------------------------------------- =
0 x
1,2
1 ≤ ≤