Non-intrusive, fast and sensitive ammonia detection by laser photothermal deflection
نویسندگان
چکیده
منابع مشابه
Photothermal deflection spectroscopy and detection.
The theory for a sensitive spectroscopy based on the photothermal deflection of a laser beam is developed. We consider cw and pulsed cases of both transverse and collinear photothermal deflection spectroscopy for solids, liquids, gases, and thin films. The predictions of the theory are experimentally verified, its implications for imaging and microscopy are given, and the sources of noise are a...
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Microcantilever sensors offer high sensitivity in the detection of adsorbed molecules based either on resonance frequency shift or changes in cantilever deflection, as both of these signals can be detected with very high resolution. Despite the high sensitivity offered by this platform, cantilevers suffer from poor selectivity due to the lack of sufficiently selective interfacial layers which c...
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In this chapter, a prototype small photothermal deflection apparatus was constructed on a laboratory bench. Not including excitation laser, data collection computer, and gas pumps, the apparatus fits on a bench space with a footprint of about 10 cm x 10 cm. This is a prototype apparatus that will be miniaturized in future assemblies. The apparatus was tested relative to the conventional laborat...
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متن کاملDetection of photothermal deflection signals with conjugate masks.
A new detection technique for photothermal deflection spectroscopy and photoacoustic deflection spectroscopy is presented. The technique uses a pair of matched multiple slits placed in the path of the probe beam and oriented to block the probe light from the detector in the absence of a deflection signal. Significant improvement in the signal-to-noise ratio and in the frequency bandwidth compar...
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ژورنال
عنوان ژورنال: Atmospheric Environment
سال: 1995
ISSN: 1352-2310
DOI: 10.1016/1352-2310(95)00066-8