The Teledyne ML 9841AS Nitrogen Oxides Analyzes uses gas-phase chemiluminescence detection to perform continuous analysis of nitric oxide (NOx), total oxides of nitrogen (NOx) and nitrogen dioxides (NOx).

The Teledyne ML 9841AS analyzer design represents an advance in nitrogen oxides analysis technology archived primarily by using adaptive microprocessor control of a single measurement channel. The instrument consists of a pneumatic system, an NO2 to NO converter (MOLYCON), a reaction cell, photomultiplier tube and processing electronics.

The analysis of nitrogen oxides by means of chemiluminesence is generally acknowledged to be in the best direct measurement technique. The method is based on the luminescence of an activated molecular NO2 species produced by the reaction between NO and O3 in an evacuated chamber. The NO molecules react with ozone to form the activated species, NO2, according to the reaction mechanism:

NO + O3 à NO2 * + O2

As NO2* reverts to \a lower energy state, it emits broad-band radiation form 500 to 3,000 nm, with a maximum intensity at approximately 1,100nm Since on NO molecule is required to form one NO2* molecule, the intensity of the chemiluminesence reaction is directly proportional to the NO concentration in the sample.

Note that the chemiluminesence reaction only occurs between O3 and NO. Consequently, analysis of NO2 to NO conversion is accomplished with a catalytic converter, the MOLYCON, that pneumatically switches in and out of the sample stream in six second cycles. This switching creates a time-phased sample stream composed of NO and NOx samples. The NOx cycle measures both the NO and the NO2 in the sample by use of the MOLYCOM, while the NO cycle measures only the NO. The NO2 concentration is derived by subtracting the NO signal from the Nox2 signal.

FEATURES:

• High range NO measurement capabilities. The Teledyne ML 9841AS is specially designed for systems applications with a range of 0-1000 ppm. Please see specifications for more detailed information.

• Because the Teledyne ML 9841AS has no chopper, there is no need to replaces belts or motors.

* Internal data logging capability. Optional internal floppy disk data storage provides additional data backup.