The analysis of error in trace gas concentration measurements by intermodulated photoacoustic stark spectroscopy (IMPASS)
نویسندگان
چکیده
Data collected in an actual IMPASS experiment with a static gaseous mixture (methyl fluoride/ethylene/nitrogen) of preselected concentrations were analyzed with respect to uni(bi)modality, symmetry, skeweness and kurtosis. Bimodal probability distribution function is significantly different from Gaussian suggesting the presence of "mixed" data in the measurements; the potential cause for this phenomenon is discussed.
منابع مشابه
Photoacoustics: an acoustic method for trace gas measurements
The photoacoustic (PA) effect, the generation of sound by the absorption of pulsed or modulated light, has been known since the famous experiments of Alexander Graham Bell in 1880. Scientific and practical applications of the photoacoustic technique have been considerably promoted by the invention of laser, which is an ideal light source for photoacoustics. Recently, photoacoustic detectors pla...
متن کاملBeat frequency quartz-enhanced photoacoustic spectroscopy for fast and calibration-free continuous trace-gas monitoring
Quartz-enhanced photoacoustic spectroscopy (QEPAS) is a sensitive gas detection technique which requires frequent calibration and has a long response time. Here we report beat frequency (BF) QEPAS that can be used for ultra-sensitive calibration-free trace-gas detection and fast spectral scan applications. The resonance frequency and Q-factor of the quartz tuning fork (QTF) as well as the trace...
متن کاملPhotoacoustic Spectroscopy with Quantum Cascade Lasers for Trace Gas Detection
Various applications, such as pollution monitoring, toxic-gas detection, non invasive medical diagnostics and industrial process control, require sensitive and selective detection of gas traces with concentrations in the parts in 10 (ppb) and sub-ppb range. The recent development of quantum-cascade lasers (QCLs) has given a new aspect to infrared laser-based trace gas sensors. In particular, si...
متن کاملAdvanced quartz-enhanced photoacoustic trace gas sensor for early fire detection
A spectroscopic trace gas sensor using a distributed feedback diode laser at λ=1.53 μm and based on quartz enhanced photoacoustic spectroscopy technique is described. The sensor is capable of quasi-simultaneous quantification of trace ammonia, hydrogen cyanide, and acetylene (NH3, HCN, and C2H2, respectively) concentrations at ~100 ppbv levels with a 4s integration time. The sensor design, resp...
متن کاملCarbon dioxide and ammonia detection using 2 μ m diode laser based quartz - enhanced photoacoustic spectroscopy
Quartz-enhanced photoacoustic spectroscopy was employed for trace gas concentration measurements of CO 2 and NH 3 using a continuous wave thermoelectrically cooled, distributed feedback diode laser operating at 2 µm. A normalized noise equivalent absorptionvspace1pt coefficient, NNEA(1σ) = 1.4 × 10 −8 cm −1 W/ √ Hz was obtained for CO 2 using the R18 line of the 2ν 1 + ν 3 band at 4991.26 cm −1...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2016