Frequently Asked Questions

ChromManager

Q: How large can I make my SpecManager database?

A: The size of a LOCAL database (*.nd8 or *.nd9) can reach 2GB. It does not depend on the number of records; it depends on the size of records. In practice, it is recommended to restrict a database to no bigger than 500 MB. It speeds up the searching capabilities. Each of these records can contain about 12,000 spectra corresponding to different techniques and conditions. Each user data subwindow is limited by 16,000 fields. The size of Remote (Oracle based) database can reach 2 terra bytes.

Q: How to view peak heights?

A:

  1. On the View menu, point to Tables, and then choose Peaks.
  2. Right-click within the Table of Peaks, and choose Options.
  3. In the Table of Options, click the Height or in earlier versions H(mV) checkbox to select it and specify the settings on the right.

Q: Is it possible to display the DAD trace by selecting specific wavelength?

A:

  1. Open the LC/DAD spectra.
  2. Ensure that the chromatogram window is active.
  3. On the Operation toolbar, click MassChrom.
  4. Click Run.
  5. Ensure that the Mass Ratio button is selected.
  6. In the Mass box, type or select the desired wavelength from the DAD.
  7. Click OK.

Note that the program is essentially treating all wavelengths in a DAD as individual masses; the principles are somewhat the same whether a mass or a wavelength are used. For example, CODA can be run for fast results. Running CODA quickly eliminates wavelengths that are not critical to the components of interest if they behave like noise.

Running CODA on DAD data is generally a good idea. Only the wavelengths which are useful in differentiating the components should show up and can be selected from the table of Mass Chromatogram.

Q: How to create *.pdf files directly from chromatographs?

A: First create a report template:

  1. In the Processor window open the data file.
  2. From the Edit menu, point to User Data, and then choose Manage.
  3. The Manage Chromatograph User Data dialog box appears. Click Add and add all the needed User Fields.
  4. Click OK to close this window.
  5. From the Edit menu, point to User Data, and then choose Edit.
  6. In the Edit Chromatogram User Data dialog box that appears, double-click the Value portion in each line and fill in the information.
  7. Click OK to accept all the information you typed in.
  8. Click Save as to save the data to *.cvd format. This file will be used later while creating a report template.
  9. Click OK to close the editor.
  10. Switch to the ChemSketch window, Draw Mode. Select the Report Template tool and draw a rectangle. In the Template dialog box that appears, specify the type and objects.
  11. Click Settings, on the Fields tab, choose Selected Fields and click Load. Locate the *.cvd file that was saved previously and click Open. All the fields are now listed. Select the needed data field.
  12. Click the Styles tab and select options and fonts to view in the report.

    The settings will be different depending on if you have Chromatogram or Table in the Objects section.

  13. Finish the template and save this as a ChemSketch file.

For a single chromatogram:

  1. To create a report for a single chromatogram, open the file in the Processor window.
  2. Click the Export Report to PDF by Template button. Specify the location of the previously saved ChemSketch saved file and click OK.
  3. A prompt to specify the name and location for the *.pdf report will appear.
  4. Open the *.pdf report in Acrobat Reader and note what changes should be made to the template file. Please note that it is possible to keep the template file in the ChemSketch window open at all times. Just make the needed changes, save the file, and point to this file from the Processor window again.

Q: How do I add the correlation equation to a userís database to be able to perform a chromatography Smart Search?

A: Before doing a Smart Search, make sure all the records in the database have the Predicted Equation user field filled in.

The user must have ACD/LC Simulator and ACD/ChromManager installed.

The following steps will help to get this field:

  1. Open the database in Update mode.
  2. Double click the chromatogram to transfer it to the Processor window.
  3. In Processor window, click Transfer to LC Simulator and select Prediction mode.
  4. In the Data Input window, click Calculate to calculate the Prediction Equation. After it is calculated, click OK to transfer the chromatogram to the Optimization window.
  5. Click Copy Prediction Equation to SpecManager on the upper toolbar to attach the equation to the chromatogram in the Processor window.
  6. In the dialog box that appears, click Paste to the current chromatogram and click OK.
  7. Click Update Database. The program will switch to the Database window with the updated Prediction Equation and related fields.

Q: When the Options in the Table of Peaks is opened, some of the columns are grayed out. How do I make them active?

A: To make all of the peaks active, use the following steps:

  1. Open the file.
  2. Go to Set Noise/Peaks, click SetNoise, and select the negative peak. Accept the changes.
  3. Go to Baseline, click Auto, and accept the changes.
  4. Go to Peak Picking, and label the two biggest peaks by setting the Peak Level option or Auto.
  5. Accept the changes.
  6. Go to Integration, click Auto, and accept the changes.
  7. The options in the table will not be grayed out any longer.