New manual method for nitrogen oxides emission measurement

Calibration factors and estimation of atmospheric sulfur dioxide and fluoride by use of solid absorbents

“…However, difficulty in neutralizing the carbonate prior to the turbidimetric determination has been a serious problem (9). Recently, a NaaP04 buffer solution at 100 °C has been used to extract sulfate from Pb02 used to recover S02 from flue gases (10). The NasPCL behaves like the Na2COa in that it provides an alkaline extraction medium (pH cu 11.5) and, on cooling, preferentially complexes any Pb2+ ions, thus leaving the SO2-ions in solution.…”

“…Extraction and Isolation of PAH Compounds. A modification of the procedure described by Giger and Blumer (10) was used to separate the PAH's from other compounds that may cause spectral interference or increase the spectral background. The modified procedure provided a relatively pure mixture of PAH's within 30 h in contrast to the 72 h required by the original procedure.…”

Performance characteristics and some applications of the nitrogen oxide gas sensor

“…Liquid membrane (2,3) and coated wire (4) nitrate electrodes have been used for the determination of nitrite after a prior oxidation step into nitrate. Similar procedures have also been suggested for the determination of nitrogen oxide gases in cigarette smoke (2), combustion effluents (5), and flowing gas mixtures (6). Reduction of nitrite with either mercury metal (7) or nitrite reductase enzyme (8,9) followed by monitoring the mercury® or ammonia gas released, using an iodide ion selective electrode or ammonia gas sensor, respectively, has been described.…”

Solid Absorbent Method for Sampling and Analysis of Nitrogen Dioxide in Ambient Air

“…Two complete analytical methods employing solid absorbents as sampling media for NO2 have been published recently. The method of Levaggi 6 was applicable to ambient air sampling but showed interference from SO2; that described by Dee 10 was designed for high levels of NO 2 (>20 ppm).…”