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Optoelektroniczne sensory gazów

Bielecki Z., Wojtas J., Stacewicz T., Mikołajczyk J., Rutecka B., Mędrzycki R., Prokopiuk A.

Pomiary Automatyka Kontrola

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2013

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R. 59, nr 4

287--291

PL

W artykule przedstawiono prace dotyczące optoelektronicznych sensorów gazów oraz osiągnięcia własne w zakresie wykrywania tlenków azotu (NOx). W sensorach do wykrywania NOx zastosowano polskie lasery emitujące promieniowanie o długości fali 410 nm oraz nowoczesne kwantowe lasery kaskadowe na zakres podczerwieni. Opracowane sensory charakteryzują się czułością graniczną na poziomie ppb i mogą być zastosowane do monitoringu zanieczyszczeń atmosfery, wykrywania materiałów wybuchowych oraz w diagnostyce chorób.

EN

The paper presents an overview of a few optoelectronic technologies for gases detection. Two sensors of nitrogen oxides (NOx) are also described. In the sensors the cavity enhanced absorption spectroscopy was applied. It is characterized by a very good sensitivity and selectivity of the detection process. The main aspect of its operation bases on absorption of the light by specific compounds. The identification of the matter is determined by spectral matching of the two spectra: optical radiation and absorption lines of species of interest. In contrast to the remote detection methods, the measurements are made at the place of sampling. Polish laser diodes and modern quantum cascade lasers were used there. Laser emission wavelengths were located in the visible (410 nm) and infrared range. The detection limit of ppb level was achieved. Due to that, they can be successfully applied to monitoring of atmospheric pollution, explosives detection and in diseases diagnosis. The preliminary studies using the developed sensors showed that it was possible to detect explosives such as TNT, PETN, RDX, HMX at the level of ng. Additionally, there is also discussed application of sensors to analysis of the exhaled air. This will be particularly useful for: the early detection of a disease, the monitoring of the therapy, the monitoring of the greenhouse exogenous (bacterial emissions or toxins), or the analysis of metabolic gases.

2

Ultrasensitive laser spectroscopy for breath analysis

Wojtas J., Bielecki Z., Stacewicz T., Mikołajczyk J., Nowakowski M.

Opto-Electronics Review

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2012

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Vol. 20, No. 1

26-39

EN

At present there are many reasons for seeking new methods and technologies that aim to develop new and more perfect sensors for different chemical compounds. However, the main reasons are safety ensuring and health care. In the paper, recent advances in the human breath analysis by the use of different techniques are presented. We have selected non-invasive ones ensuring detection of pathogenic changes at a molecular level. The presence of certain molecules in the human breath is used as an indicator of a specific disease. Thus, the analysis of the human breath is very useful for health monitoring. We have shown some examples of diseases' biomarkers and various methods capable of detecting them. Described methods have been divided into non-optical and optical methods. The former ones are the following: gas chromatography, flame ionization detection, mass spectrometry, ion mobility spectrometry, proton transfer reaction mass spectrometry, selected ion flow tube mass spectrometry. In recent twenty years, the optical methods have become more popular, especially the laser techniques. They have a great potential for detection and monitoring of the components in the gas phase. These methods are characterized by high sensitivity and good selectivity. The spectroscopic sensors provide the opportunity to detect specific gases and to measure their concentration either in a sampling place or a remote one. Multipass spectroscopy, cavity ring-down spectroscopy, and photo-acoustic spectroscopy were characterised in the paper as well.

3

Spektroskopia strat we wnęce optycznej

Bulska E., Ruszczyńska A., Stacewicz T., Snopczyński T.

Analityka : nauka i praktyka

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2009

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nr 3

4-8