GE MOA 280i, Руководство по эксплуатации и обслуживанию

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GE Analytical Instruments ©2006
11-1
DLM 14291 Rev. A
11.
INSTALLATION AND SETUP: LIQUID MEASUREMENTS
Measurement of nitric oxide and its reaction products in liquid samples is
performed using a purge vessel. An inert gas bubbles through chemical reducing
agents, to convert oxidation products back to nitric oxide. Samples are injected
through a septum into the purge vessel and the inert gas carries the NO over to the
NOA for detection. Calibration is performed by injection of standard solutions of
the analyte.
Supplies
The following items are required to perform liquid measurements:
Gases
A cylinder of Helium, Nitrogen or Argon equipped with a two-stage regulator is
required for the purge vessel. The outlet pressure of the regulator is < 5 psi,
typically 1-2 psi.
Reagents
Deionized water containing < 1 µM nitrite/nitrate.
Nitrite – Glacial acetic acid, sodium or potassium iodide, and sodium or potassium
nitrite.
Nitrate – Concentrated hydrochloric acid or 1 M HCl, vanadium (III) chloride,
sodium or potassium nitrate, 1 M sodium hydroxide, sodium hydroxide pellets or
50% NaOH
(aq)
.
Nitrosothiols – Thiols (glutathione, N-acetyl cysteine, albunin, hemoglobin)
PBS, Cu(I)Cl, cysteine, or I
2
, CuSO4, HgCl
2
, reagents for nitrite
Iron-bound NO – KCN, K
3
FeCN
6
Lab Equipment