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1. Clicking into the appropriate workspace (Linescan), capture an image as described in the above section.
2. Highlight the line and drag/adjust the endpoints to the desired position.
3. Set Point count of the line scan. Alternatively select Distance [μm] between measurement points. The distance between points and electron beam spot size is shown in a display and will change depending on whether Point count or Distance [μm] has been selected. The calculation of the spot size depends on the voltage used.
4. Click on the dropdown arrow on the Acquire button to open the Acquisition menu. Select the desired parameters.
   1. Set Acquisition parameters: 
      1. Automatic:
         1. Fast (50000 counts) for major elements
         2. Precise (250,000 counts) for minor elements (recommended)
         3. Exhaustive (1,000,000 counts) for elements close to the detection limit
      2. Manual: If Manual is selected, the acquisition must be stopped manually by deselecting the Acquire button
      3. Real time: The acquisition will stop after the time entered in the dialog box has elapsed
      4. Live time: The acquisition will stop after the dead time-corrected acquisition time has elapsed
      5. Counts: The acquisition will stop after the predefined number of counts is recorded.
   2. Optionally, set Automatic Quantification if desired. If Continuous or After acquisition is selected, the spectrum is quantified during or after the acquisition. Load a quantification method using the button.
   3. Optionally, set Spectrum numbering settings if desired: the numbering will start after the entered Spectrum number.
   4. Optionally, set Auto save settings: Select Add to report to send the data automatically after acquisition to the report, and/or select Save to file to save the data automatically after acquisition via pop-up dialogue.
5. Click Acquire to acquire a spectrum. If Acquisition is set to Manual, the acquisition must be manually stopped by deselecting the Acquire button. All other acquisition parameters will automatically stop the acquisition when the set parameter (time or counts) has been reached.
6. Use the elements icon to identify elements. Elements are automatically identified by Auto ID and element list can be modified by clicking on Element ID or Finder.
7. Select elements in the thumbnail bar by ticking the boxes below the individual element images to display their profiles in the Profiles tab
8. Use the right mouse key in the scan iage to extract region of interest spectrum from the line scan.
9. Right click into the desired element to Save or Add to report, or use the I/O icon.

Image Added

Figure 3: Example of line scan.

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• Any charging present on the surface of the sample will quickly degrade the quality of EDS spectra. In order to avoid charging: 
  • Use the lowest possible accelerating voltage that is appropriate for the material and elements of interest
  • Use an even smaller beam current
  • Ensure good electrical grounding using carbon tape,
  • Perhaps remove the sample to apply a thicker C coat to improve electron transport
• One proxy for quality of spectrum is to right click on the spectra and then select Logarithmic graph display, to make visible the background curve of the spectra. The background should taper smoothly to the highest values at the accelerating voltage used, e.g. if the microscope is being operated at 10 kV, the spectra should have smooth values up to 10 kV.
• Check the non-normalized mass % totals, which ideally should be around 100% for non-hydrous minerals.
• In order to interpret mass percent oxides, it is helpful to have an idea of the anticipated mineralogy of the sample, then compare the compositions to the ideal stochiometric mineral compositions from an online mineral database such as Webminerals of Mindat.
• Technicians can share access to a number of technical books on electron microanalysis if desired.

III. Uploading Data to LIMS

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