• Can you use the
One Cue oxygen meter for BOD-measurements?
• What kinds of plastic can you use as a membrane?
• What are the experiences of users of the One Cue oxygen meter?
• What kinds of plastic can you use as a membrane?
• What are the experiences of users of the One Cue oxygen meter?
Can you use the One Cue oxygen meter for BOD-measurements?
Yes, you can. The Biochemical Oxygen Demand (BOD) is an
important measure for the total amount of biologically degradable organic matter
in (waste) water. The higher the BOD, the more oxygen the bacteria in the water
will consume to degrade it. As a result the water may become anaerobic which
causes the animals in the water to suffocate. That's why the sewer charge rates
(or whatever it's called) is based upon the BOD that you flush through your
toilet and sink.
What kinds of plastic can you use as a membrane?
You can use all sorts of plastic, unless impermeable to
oxygen (do these exist?), from rather thick lunch bags to ultra thin household
wrap. The speed at which oxygen diffuses through this plastic depends on the
thickness of the material. Thin foil gives an electrode with a high sensitivity
and short response time, but the electrical current is quite substantial, which
means vigorous stirring and a short lifetime. A thicker foil gives a lower
sensitivity en a longer response time, but the electrode lasts longer and
stirring gently will suffice.
What are the experiences of users of the One Cue oxygen meter?
The CMA/AMSTEL Instituut , inventor en seller of the Coachlab
computer interfaces tested the One Cue electrode using an amplifier and CoachLab.
Their findings:
"...The response time of the sensor is pleasantly short. The sensor is somewhat sensitive to stirring, which can be expected; stirring has to be carried out with care.
The reproducibility of a measurement hasn't been investigated extensively. The influence of the 5k potentiometer has to be studied further.
The first inspection is nevertheless positive:
It's possible to measure quickly, easily and affordable and the signal seems useable.
"...The response time of the sensor is pleasantly short. The sensor is somewhat sensitive to stirring, which can be expected; stirring has to be carried out with care.
The reproducibility of a measurement hasn't been investigated extensively. The influence of the 5k potentiometer has to be studied further.
The first inspection is nevertheless positive:
It's possible to measure quickly, easily and affordable and the signal seems useable.
