Thermo Scientific MIRAN 205B Series, Инструкция по эксплуатации

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Appendix C Scan/Calibration Procedure
C-10
F. CALIBRATION
1. Calculate five injection volumes that cover the complete concentration range
(also see Chapter 12). E.g., if the concentration is 0 to 1000 ppm, the
concentrations should be approximately 200, 400, 600, 800, and 1000 ppm.
For liquid injection volumes
3
, use the formula:
 



















d
M
R
P
10
V
C VI
3
T
For gas injection volumes
3
, use the formula: VI = (C) (V
T
).
Where:
VI = injection volume in microliters (

L)
C = concentration volume in parts per million (ppm)’
V
T
= total volume of cell and calibration system in liters (2.24L)
d = Liquid density (g/cm
3
)
M = Molecular weight of sample






 
C 25 at
24.4
1
gas of me Molar volu
R
P
Note
: In the above example, 200 (the lowest concentration ) x 2.24 (the cell
volume) = an injection volume of 448

L. Since most syringes are not precise
enough to measure an injection volume of 448

L, select an injection volume
that can be accurately measured by the syringe. In the above example it will
be 450

L. Transpose the formula to C = V
i
/V
T
, and solve for the
concentration (C). In this example, C = 450/2.24 = 200.1. Record both the
concentrations and injection volumes.
2. From the Main Menu select "1=Analyze/Start"
3. Select "1=New Zero"
4. At the prompt “Install chemical filter”, attach the Closed Loop Calibration
System and turn the pump on. Select "Enter=Continue"
5. Allow instrument to purge with "Zero Air" or clean air.. The instrument will
purge for 1 minute then proceed to set the Zero.
6. At the prompt for "Install Particulate filter", keep the Closed Loop Calibration
System attached. Press "Enter=Continue" and allow the instrument to purge
the Zero Air sample. When the purge is complete, select

or

until the
Absorbance screen appears. Verify that the absorbance equals zero(+/- .0010).
3
Depending upon the compound, either a gas or liquid may be injected,. Many compounds (e.g., benzene)
are not readily available in gaseous form, and are therefore inserted into the pump as a liquid. The pump
evaporates the liquid before it is introduced to the analyzer.