abstract |
APPARATUS AND METHOD FOR NO-NO2 ANALYSIS IN WHICH A SAMPLE GAS IS PLACED IN A PRESSURE SAMPLE CELL; MEASUREING RADIATION IN THE 410-600 NM. RANGE PASSED THROUGH THE CELL AND DETECTED; OXYGEN-CONTAINING GAS INTRODUCED INTO THE CELL UNDER PRESSURE; THE ABOVE RADIATION AGAIN PASSED THROUGH THE CELL AND DETECTED; AND THE TEMPERATURE CONTROLLED AFTER INTRODUCING THE OXYGEN-CONTAINING GAS. PREFERABLY 4 ATMOSPHERES OF SUBSTANTIALLY PURE OXYGEN CONSTITUTE THE OXYGEN-CONTAINING GAS; THE ABOVE MEASURING RADIATIONS HAS A WAVELENGTH OF ABOUT 436 NM.; RADIATION OF ABOUT 546 NM. IS PASSED THROUGH CELL FOR REFERENCE PURPOSES; AND THE PRESSURE WITHIN THE CELL IS ALSO CONTROLLED. WHEN PRESENT, RADIATION BELOW ABOUT 410 NM. SHOULD BE EXCLUDED FROM THE CELL. ALTERNATIVELY, THE MEASURING RADIATION MAY BE PASSED THROUGH THE CELL ONLY AFTER THE OXYGEN-CONTAINING GAS HAS BEEN INTRODUCED THEREIN. D R A W I N G |