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The pXRF should be set up in a location that is isolated with minimal people working nearby, but also be easily accessible with sufficient space to scan section halves. This should be done without disrupting other workstations or without danger of dropping or mishandling section halves or core material. Typical locations have been the Downhole Lab bench, Paleo Lab bench or correlators' station, if they are not sailing, but consult with the scientists and co-chiefs for a preferred location. Once set up and it has been established which scientists will be trained to use the device (usually two scientists per shift), dosimeter rings will be issued to each person that will be operating the device and the training technician. Each dosimeter ring has a unique ID and is assigned to a specific person.
Application and Settings
The current application can be changed by selecting ‘Application’, choosing a different application type and selecting ‘OK’. This device has six applications installed. The best application for our purposes is GeoExploration. Each application has different scanning parameters which preferentially pick up some elements better than others. The device will keep the chosen application until manually changed.
Some application settings, such as beam scan duration, can be adjusted by selecting ‘Settings’ on the main display screen. Select ‘Ok’ when finished adjusting the following settings:
- Duration: This screen will display the number of phases used by the current application. The time in seconds spent on each phase can be adjusted or set to unlimited (ending when the trigger is released). Note: The longer the scan time, the greater the accuracy and precision and the lower the error. For geological samples, 1 minute per phase or longer is not uncommon, but not required.
- First Result/Test: This is the number of seconds before results will be shown on the display once a measurement has been triggered.
- Trigger Active: The trigger can be set to ‘Auto’ or ‘Manual’ by selecting this button.
- Auto: The measurement proceeds by pressing and releasing the trigger. Preferred.
- Manual: The trigger must be pressed for the duration of the measurement. If the trigger is released at any time during the measurement, measuring will stop.
Edit Sample Information
On the main display, click the ‘Edit Info’ button in the middle of the bottom row of buttons. This screen (Figure 4) is where the sample information is entered. All fields in the right column are editable by double clicking and should be reviewed and changed for each sample:
- Sample Type:
- Standard – a powdered standard in a sample cup
- SHLF – a measurement taken directly on a section half or of a piece from a section half
- PWDR – a powdered sample in a sample cup
- Discrete – for any other samples
- Expedition: The current expedition, example 397.
- Site and Hole: The site and hole the sample was taken from, example: U1586A.
- Core/Section: The core number with letter indicating the core type and the section in that core that is being measured or that the sample was taken from, example: 1H/6. If measuring a standard, enter the standard name, example: BCR 2 or BHVO 2.
- TextID: The unique sample number for every sample. This is found on the lower right corner of the typical sample label, example: SHLF11754181. Note: If the device is connected to the laptop and using Bruker RemoteCtrl software, use the scanner to enter the TextID. If measuring a standard, use the information from the appropriate QAQC label provided. If a standard does not have a QAQC label, leave this field blank.
- Top Offset (cm):
- For a section half or sample from a section half (discrete, unaltered piece), this is the distance from the top of the core section, example: 34 or 101.5 (Do not put a range, just the beginning number of the measured area or sample).
- For powdered samples and standards, use 0.
Comment: Use this to provide any additional information, such as a physical description for reference or to indicate a replicate measurement.
Click 'OK' in the lower left corner of the screen. The display will return to the main display screen.
- Login to the computer using the login information on top of the computer keyboard.
- First, turn on the instrument. To do this press the button on top of the device screen and hold it for a few seconds (Figure 1).
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