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8.1.2
Water-Vapor Saturated Air
Enclose wet cotton wool into a flask (e.g. DURAN flask) with a lid
prepared with holes for the oxygen sensor and a temperature
sensor from
PyroScience
. Typically about 1/3 to 1/2 of the flask
volume is filled with the wet cotton wool, while the other volume
fraction is left free for inserting the tip of the oxygen sensor, and
optionally also the temperature sensor. Otherwise, follow the
calibration procedures given in chapter 7.
8.1.3
Air Saturated Water
Fill an appropriate amount of water into a flask (e.g. Duran flask)
with a lid prepared with holes for inserting the oxygen sensor and a
temperature sensor. Stream for about 10 minutes air through the
water with an air stone connected to an air pump (available as
commercial equipment for fish aquaria). Alternatively, if no air
pump is available, fill water into the flask leaving >50% air in the
head space, close it with a lid and shake the flask strongly for about
1 minute. Open the lid shortly for ventilating the headspace with
fresh air. Close it again and shake the flask for 1 more minute.
Insert the oxygen sensor, and optionally also the temperature
sensor, into the flask and ensure that the tips of the sensors are
immersed in the water. Otherwise, follow the calibration
procedures given in chapter 7.
Please consider that streaming air through water may cause
cooling of the water. Ensure a
correct temperature
determination
!
