horiba 6582S-10C, Инструкция по эксплуатации

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 Impact of temperature
The potential gradient measured by the ion electrode method is impacted
by the temperature of the sample solution in accordance with the Nernst
equation. The higher the temperature is, the larger the potential gradient is.
The lower the temperature is, the smaller the potential gradient is.
The standard solution in calibration and the sample solution in
measurement shall have almost the same temperature. Match the
temperature as close as possible.
Table 5 Relationship between temperature of
ion selective electrode and theoretical slope
The optimal way to minimize the impact of temperature on the
measurement of the K
+
concentration is to reduce the difference between
the temperature of the standard solution in calibration and the temperature
of the sample solution in measurement to ±1°C.
The following table shows the change in the potential gradient of the
potassium ion selective electrode depending on the temperature.
Table 6 Relationship between temperature of
potassium ion selective electrode and theoretical slope
Unit: mV/decade (mV/concentration change of 10 times)
Temperature (°C)
0 10 20 25 30 40 50
Theoretical
slope
Monovalent
ions
54.20 56.18 58.16 59.16 60.15 62.13 64.11
Divalent
ions
27.10 28.09 29.08 29.58 30.07 31.07 32.06
Temperature
[°C]
Theoretical slope of potassium ion selective electrode
[mV/decade]
0 54.20
10 56.18
20 58.16
25 59.16
30 60.15
40 62.13
50 64.11