How to try the DHA demo project

In this chapter, you can find instructions on how to try the DHA Extension using the DHA demo project.

Step 1

In the System Configuration window (menu Clarity - Configuration…), open the Instrument Type Setting dialog via the button, and check the DHA option on Instrument 1.

For more details see also chapter Installation.

Step 2

After closing the System Configuration window, open Instrument 1. Now, open the DHA demo project: in the Login Dialog, select DEMO_DHA in the Select Project drop-down list, and click the OK button.

Step 3

Open the Chromatogram window (it can be opened by clicking on the menu Window - Chromatogram). In the lower part of the Chromatogram window, you can see the new DHA tab. Open the chromatogram N_PARAFFINS_FOR_ASTM6730.PRM. This file is a calibrated n-paraffins standard.

Step 4

Select the DHA tab, and on the right side of the bottom pane, you will see the DHA settings pane. There you can choose a norm for your DHA Method and create a new DHA Calibration.

The settings from the DHA Method field are saved in a special .DHA (DHA Method) file, which can be used for multiple chromatograms. Click the Open… button to browse the Clarity Installation directory (by default C:\CLARITY\DataFiles). In the DEMO_DHA subdirectory, select the ASTM6730.dha file. The DHA Method will be loaded, and the active chromatogram results will be automatically recalculated according to the set norm and Group Results parameters. Note that the linked calibration ASTM6730_C5-C15-RI.cal is a non-DHA calibration that serves only for the calibration of the present n-paraffin sample peaks. Due to this, the DHA Results table header contains a warning.

For more details see also chapter DHA Settings .

Step 5

The norm selected in the DHA Settings pane will be used when creating a DHA Calibration. Click the Create DHA Calibration button, and the Create DHA Calibration dialog will be displayed. Retention times from the opened calibration standard will be automatically imported. After clicking the Create button, the Calibration window will open. Save the created calibration.

Step 6

Close the Calibration window, and in the Chromatogram window, open an unknown sample from the Demo_DHA project, for example ASTM6730_455.PRM. Click the DHA tab, and in the lower part of the DHA Settings pane, you will see that this chromatogram already has a linked calibration file ASTM6730. Note that this is the same file as set in the Calibration File field in the Results tab of the Chromatogram window. You can change it to the calibration created in Step 5.

Step 7

In the DHA Results sub-tab of the DHA tab, you can see the calculated results of compounds identified in the chromatogram. You can also switch to the DHA Group Results tab, where the results are presented in a pivot table. The table contains the sums of all compounds per group or carbon number.

If there is a compound in the Result Table that cannot be identified by the selected norm, the Status column displays a warning. This can be caused by the compound name as set in the calibration not corresponding to the compound name in norms. If you need to link a compound from the chromatogram with a matching compound name in norms, click Edit Link Table…, and in the displayed dialog, link the compound name from the chromatogram with the name in norms.