Vapor Calibration
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Values and screen shots in this topic are for a typical vapor calibration for pyridine. |
When using the optional vapor generator, it must be calibrated for the type of vapor to be used. Associating the analysis data with a vapor generator calibration file allows the conversion of peak area data to volume data. The calibration can be performed either before or after performing the analysis. A single calibration file can be used with multiple analysis files.
- Go to . Enter a calibration file name (.CAL). Click OK, then click Yes to confirm.
- Complete the remaining fields on the Sample Description window as needed.
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If the window displays in Basic presentation, click Advanced in the view selector drop-down at the bottom of the window. |
- Select the Analysis Conditions tab. Click Insert, then select Vapor Calibration.
- Complete the window using these entries:
Selections |
Description |
Calibration Gases [group box]
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Select Helium. Enter a flow rate of 50 for each. |
Reflux Temperatures [group box] |
Enter a minimum of 70 and maximum of 80. |
Flask Temperatures [group box] |
Enter a minimum of 80 and maximum of 100. |
Number of steps [text box] |
5 |
Recording Options [group box] |
Select the signal. It is a good idea to select this option when using helium for the carrier gas. It improves the performance of automatic peak picking. |
Zones [button] |
Field |
Enter |
TCD Detector |
Block zone
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100 |
Filament
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175 |
Valve Zones |
Cold trap
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110 |
Analysis
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110 |
Loop
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110 |
Vapor generator
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20 |
Vapor Generator |
Reflux
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20 |
Flask
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20 |
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Outputs [button] |
See Auxiliary Inputs and Outputs. |
- Click OK to close the Set Temperature Zones window, then again to close the Vapor Calibration Experiment window.
- Click Save As, enter a file name, then click Close.
- Go to . Click Browse and select the sample file just created.
- Click Next three times to accept the values contained in this sample file. These values can be edited, however, no changes are needed for this example. Click Start.
- Use the other views of the Analysis window to observe the progress of the analysis.
- When the analysis completes, close the Analysis window.
- When the displayed sample temperature reaches the ambient temperature, open the furnace. Use gloves and remove the sample tube. These fields do not require editing; the Reflux and Flask temperatures entered on the Vapor Calibration Experiment window are used.
- To edit the calibration file, go to .
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Use the cotton gloves provided in the accessory kit when handling heated surfaces. These cotton gloves are not intended to protect hands when heated surfaces are above 60 °C.
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- Select Load Calibration Data and select the sample file for this calibration; the data contained in the file are automatically loaded.
- Access the Calculations document on the Micromeritics web page (www.micromeritics.com) for information on calculating the volume of each vapor injection, then enter the values for each peak.
- Assess the plot, Goodness of Fit, and Coefficients to decide if the calibration file is acceptable. Use your laboratory’s standards to determine what level of linearity is acceptable. As a general guideline, use a calibration file with a very low value for Goodness of Fit (less than 1 to 2% of the signal), when 1st or 2nd Degree is specified.
- To delete any peaks that are outliers, highlight the peak data in the table and click Delete Peak. Evaluate the results when the degree is changed (select a different degree from the drop-down list).
- When satisfied with the calibration file, click Save then click Close.