ADVANTAGES:

• Both ¹³C and ¹⁸O Isotopic Ratios are monitored in real-time

• Single TE cooled Quantum Cascade Laser (QCL)       

•  2 matched absorption cells, 7 m.

• No pre-concentration is required

• Measurement precision:

0.2δ  in one second, or

0.03δ in 300 sec.

• Fast time response:  (1/e) response time of 0.05 sec in the 0.3 liter sampling cell

• Compact 19 inch rack mountable system

Click here for a Typical isotopologue-specific spectral scan in the 2310 cm^-1 region, taken from the TDLWintel data acquisition screen, using the dual-cell QCL spectrometer. 

ADVANTAGES of Novel Dual Cell Approach (sample + reference)

(1) optical simplicity and higher optical power
(2) negligible spectral interference between the two isotopic species. 

• The two multi-pass cells are thermally coupled.

• Cell temperatures measured to a relative precision of 1 mK to minimize compensation for the temperature sensitivity.

• Temperature control of entire optical bench and electronics minimizes drifts in laser line width, frequency, tuning rate and power variation.

TECHNICAL SPECIFICATIONS:

 Technical specifications for the CO₂ Isotope Analyzer with both LN2-cooled detectors and TE-cooled detectors are given below: 

1.  The RMS noise definition is defined by the 1 sigma standard deviation of a data stream with a 1 Hz sampling frequency for the ratio of the minor isotope to the major isotope.  The values given are for simultaneous detection of all three isoptopologues.

2.  The absolute concentrations are based on the periodic addition of calibration gases using automated solenoid valve (included).

3.  The sampling frequency of 1 to 20 Hz is the electronic processing speed.  The gas exchange time constant (1/e) in the 0.3 liter volume sampling cell is tau=0.05 seconds with a 420 liter-per-minute vacuum  pump (optional). 

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