Thermo Scientific Orion Versa Star Pro, Руководство пользователя

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Chapter 4
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pH, pH/ISE and pH/LogR Measurement Modules
70
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Orion Versa Star Pro Meter User Manual Thermo Scientific
Single Analate Addition
In single analate addition, the first measurement is in a known standard solution containing the
same type of analate of interest as the sample. The second measurement follows the addition
of the unknown sample. The concentration of the unknown sample is then calculated. Refer to
the following table to choose the correct standard concentration and volume of addition.
Amount of analate to be added per 100 mL
of standard
Standard concentration compared to expected
sample concentration
1 mL 100 times more concentrated
5 mL 20 times more concentrated
10 mL 10 times more concentrated
1. Prepare the ion selective electrode (ISE) according to the instructions in the electrode user
manual. Prepare all required solutions (ionic strength adjusters, standards, etc) and review
any special requirements outlined in the electrode user manual. Connect the ISE, and any
other electrodes to be used, to the module inputs on the selected channel.
2. Determine the ISE slope as directed in the electrode user manual.
3. In the measurement mode, press the channel key until the channel with the pH/ISE
module with ISE connected is shown. If needed, press the mode key until ISE
Measurement is shown as the measure mode and use the
ISE Mode Menu to set the
Electrode Type.
4. In the measurement mode, press the setup key.
5. Press the  ,  ,  or  key to highlight Channel 1, Channel 2, Channel 3 or Channel 4
and press the f3 (Select) key.
a. Select the appropriate channel number that the ISE is connected.
6. Press the  or  key to highlight Incremental Techniques and press the f3 (Select) key.
7. Press the  or  key to highlight Single Analate Addition and press the f3 (Select) key.
8. Press the f3 (Clear) key as needed to delete the displayed slope value. Use the numeric
keypad to enter the ISE slope value determined in step 2 and press the f2 (Accept) key.
9. Enter the standard volume using the numeric keypad and press the f2 (Accept) key.
10. Enter the total volume (standard volume plus added ISA volume) using the numeric keypad
and press the f2 (Accept) key.
11. Enter the standard concentration using the numeric keypad and press the f2 (Accept) key.
12. Rinse the ISE and any other electrodes in use with distilled water or rinse solution required
for that electrode. Blot the electrode dry with a lint-free tissue or shake the electrode, place
into the prepared standard and press the f2 (Next) key.