ekS - Instytut Agrofizyki im. Bohdana DobrzaÅskiego PAN w Lublinie ...
ekS - Instytut Agrofizyki im. Bohdana DobrzaÅskiego PAN w Lublinie ...
ekS - Instytut Agrofizyki im. Bohdana DobrzaÅskiego PAN w Lublinie ...
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chamber and the freezer, only one working at a t<strong>im</strong>e. An independent temperature<br />
sensor connected to the main security switch was applied to disconnect all power<br />
devices in the system in case of reaching upper l<strong>im</strong>it temperature, Tz = 65 ºC,<br />
inside the chamber.<br />
Fig. 19.<br />
Block diagram of the laboratory setup for the determination of temperature effect on soil<br />
dielectric permittivity<br />
Each TDR measurement started when the air temperature inside the chamber,<br />
Tp, the temperature of the measured soil sample, T0, T1, .. or T7, and the<br />
regulation temperature reached the same value with ±0.4 ºC tolerance. The<br />
decrease of the temperature tolerance was possible but it would cost the<br />
significant increase of t<strong>im</strong>e to stabilize the temperature in the soil sample and the<br />
chamber. The complete measurement cycle at six temperature values, from 5 ºC<br />
to 55 ºC in 10 ºC increments, for the set of eight soil samples took about 12 hours<br />
and starting from the 4-th cycle the measurable decrease of TDR water content<br />
45