DHA Settings
In this pane you can set up the DHA Method - choose the norm and edit its specific parameters.
Chromatogram window - DHA - DHA Settings
Shows the currently opened DHA Method. All settings in the DHA Method are saved in the *.DHA file, which is independent on the method opened from the Instrument window. The last opened DHA Method used in the Chromatogram window is saved in the project file (for more details, see also the chapter (for more details see also chapter Project)).
New
Creates a new DHA Method with default settings.
Open
Displays the Open DHA Method dialog where you can open the DHA Method you want to use.
Save
Saves the settings of the current DHA Method.
Save As…
Opens the Save As dialog for saving the DHA Method into a new file.
Select the norm you want to use for your calculations.
Caution:
Norms available in this menu depend on the p/n of your purchased DHA Extension. See the chapter the chapter "Specification"
In the case you select a norm you have not purchased, an error dialog is displayed:
Error when selecting a non-available norm
By clicking on the link, you can display the help containing the conditions valid to each norm.
Select units used in the DHA Group Results.
By clicking this button, the Create DHA Calibration dialog is displayed. It allows you to create a DHA Calibration and display it in the Calibration window.
The DHA Calibration is created from the opened standard chromatogram, which must contain from 6 to 11 calibrated peaks from the n-Paraffins standard sample. Clarity will perform an interpolation through the points from the n-Paraffins standard and automatically calculate Retention Times for all other peaks from the Retention Indexes in the norm.
The Compound Names for the DHA Results and the Group Results are retrieved from the Calibration Table.
In situations, when the Compound Names in norms have different names than the ones you have saved in your calibration, you can use Link Table for linking those Compound Names and ensure that all compounds are included in the selected norm calculations. For more details see also chapter Link Table
Opens the Link Table dialog, where you can edit the links between compound names in calibrations and norms.
Chromatogram ③
This parameter defines the column dead time in minutes. This field corresponds to the same field in the Performance tab.
Caution:
The Unretained Peak Time is used depending on the Retention Indexes use Log. Interpolation with Unretained Peak option in the Calibration Options. When this option is not checked, the retention indexes are calculated using linear interpolation. When it is checked, logarithmic interpolation with unretained peak time is used.
This parameter defines the value in % of compounds which are undetected in the DHA Results - column % Weight (% Volume is calculated from the % Weight column). The weight of the particular detected compound will be calculated as: 100-(Undetected Compounds) [%].
Calibration File (Peak Table) ④
This field and group of buttons work identically as the buttons in the Results tab.
Set…
Opens the Open Calibration dialog for setting the linked Calibration.
None
No Calibration will be used.
View…
Displays the linked Calibration.