GE MOA 280i, Руководство по эксплуатации и обслуживанию

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GE Analytical Instruments ©2006
9-5
DLM 14291 Rev. A
Figure 9- 3: Chamber Sampling Setup.
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The stopcocks are positioned to seal the chamber for short period of time
(typically 5-15 seconds depending on the size of the head-out chamber). During
this time, zero air flows directly to the NOA.
•
The stopcocks are repositioned to flush the accumulated NO to the NOA.
Replicate measurements can be performed by repeating these steps while the
animal is in the chamber.
Since the chamber will fill with ambient air when the animal is inserted or
removed from the chamber, sufficient time to thoroughly flush the chamber
before collection is required. The NOA can be used to determine when all of the
NO has been removed from the chamber.
The duration of the collection period will depend on: the size of the chamber, the
size of the animal and the tidal volume/respiratory rate of the animal. Since the
chamber is sealed, the animal can become hypoxic if the collection period is too
long. The best procedure is to start with a short collection period to see if enough
NO accumulates to give a significant increase above the background NO and
increase the period if not enough NO accumulates.