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1
Content available remote Photosynthetic signatures of microbial colonies covering submerged hard surfaces as novel trophic status indicators : Baltic Sea studies
Boniewicz-Szmyt Katarzyna, Grzegorczyk Maciej, Pogorzelski Stanisław J., Rochowski Paweł
Oceanologia
|
2023
|
Vol. 65 (1)
194--201
EN
The study aimed to determine photosynthetic signatures, i.e. photosynthetic energy storage (ES) efficiency and photoacoustic spectra of pigment-containing biofilm communities attached to submerged solid substrates in relation to the temporal variability of the trophic state of natural water. Biofouling phenomenon signatures on artificial solid surfaces, deployed in the shallow Baltic Sea waters (Gulf of Gdańsk, Poland) for a specific period of time, were determined over a three-year period using improved photoacoustic spectroscopy apparatus based on closed cell geometry. Selected chemical parameters (oxygen, nitrogen and phosphorus concentrations) and biological productivity (primary production and Chlorophyll a; hereinafter abbreviated as Chl a) of the water body were obtained from the SatBałtyk System platform (http://satbaltyk.iopan.gda.pl) and used as comprehensive data. As a result, close cross-correlations between photosynthetic energy storage and PAS amplitude spectra and the seawater chemical parameters were demonstrated. As found, ES was negatively correlated with concentrations of biogenic elements (correlation coefficient R given in brackets): O (–0.67), P (–0.81), N (–0.76), and positively correlated with concentrations of Chl a (0.82) and primary production (0.39). As periphyton is believed to respond dynamically to water quality and environmental stresses, its photosynthetic system features can be used as novel, modern and robust indicators in marine bioassessment, in addition to traditional trophic state indices based on chemical analysis.
2
Content available Ozone detection based on an nitrogen oxide photoacoustic spectroscopy system and chemical reaction
Jin Huawei, Ji Haitao, Wang Haowei, Li Shuo
Environment Protection Engineering
|
2023
|
Vol. 49, nr 4
73--87
EN
Ozone is known as a “god-given purifying agent”, and its quantitative detection is of great significance. A low-cost photoacoustic spectroscopy (PAS) which is based on absorption at the low-power blue diode emitting at 403.65 nm has been used for nitrogen oxide (NO2) concentration measurements. According to the formula of nitric oxide (NO) reaction and ozone (O3) production of NO2and the differential detection method, a dual-channel PAS system for O3 detection is reported. The consistency of NO2detection with the dual-channel photoacoustic spectroscopy system is good by contrast. The coefficient of determination R2 can still reach 0.846. An intercomparison between the system and a cavity ring-down system (CRDS) was shown to verify the accuracy. The results showed a linear correction factor (R2) of 0.943 in a slope of 0.862±0.002, with an offset of (0.773±0.128) ppb. In addition, the measurement of 3using the dual-channel cavity photoacoustic spectroscopy technique was deployed. These observations indicate that 3concentrations can be effectively observed with the dual-channel PAS instrument.
3
Content available Application of quantum cascade lasers to trace gas detection
Bielecki Z., Stacewicz T., Wojtas J., Mikołajczyk J.
Bulletin of the Polish Academy of Sciences. Technical Sciences
|
2015
|
Vol. 63, nr 2
515--525
EN
The potential of Quantum Cascade Laser technology has been recently harnessed in industry, medicine and military to create a range of original infrared gas sensors. These sensors have opened up many new applications due to compact size, excellent sensitivity, robust construction and low power requirements. They rely on infrared absorption spectroscopy to determine identity and quantity of gases. The measurement of these gases has relied on different technologies including multi-pass spectroscopy, photoacoustic spectroscopy, cavity ring down spectroscopy, and their various modifications. In this review paper some technologies are described in terms of its advantages/disadvantages in many application. The results of own works about methane, ammonia, nitric oxide, nitrous oxide, and carbonyl sulfide detection are presented as well.
4
Content available Comparison of the CRLC models describing the Helmholtz type cells for the nondestructive photoacoustic spectroscopy
Chrobak Ł. B., Maliński M. A.
Metrology and Measurement Systems
|
2014
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Vol. 21, nr 3
545--552
EN
The photoacoustic cell is the heart of the nondestructive photoacoustic method. This article presents a new simple lumped-components CRLC model of the Helmholtz type photoacoustic cell. This model has been compared with the well known literature models describing the Helmholtz type cells for photoacoustic spectroscopy. Experimental amplitude and phase frequency data obtained for the two photoacoustic cells have been presented and interpreted in a series of models. Results of the fitting of theoretical curves, obtained in these models, to the experimental data have been shown and discussed.
5
Content available remote Ultrasensitive laser spectroscopy for breath analysis
Wojtas J., Bielecki Z., Stacewicz T., Mikołajczyk J., Nowakowski M.
Opto-Electronics Review
|
2012
|
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.
6
Content available remote Energy efficiency of near infrared cobalt luminscence in ZnSe:Co determined by a photoacoustic method
Chrobak Ł., Maliński M., Strzałkowski K., Zakrzewski Z.
Opto-Electronics Review
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2012
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Vol. 20, No. 1
91-95
EN
The paper presents results of computations of the energy efficiency of the cobalt luminescence in ZnSe:Co determined by the photoacoustic method. The transmission spectra, photoacoustic experimental and theoretical spectra, and the frequency dependence on the photoacoustic amplitude characteristics are presented. From them, the energy efficiency of Co²⁺ the near infrared luminescence (3200 nm) was computed in the frame of new proposed photoacoustic model of computations of the luminescence energy efficiency.
7
Content available remote Photoacoustic method of determination of quantum efficiency of luminescence in Mn²⁺ ions in Zn₁₋xBexMnySe crystals
Maliński M., Chrobak Ł., Zakrzewski J., Strzałkowski K.
Opto-Electronics Review
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2011
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Vol. 19, No. 2
183-188
EN
This paper presents step by step the procedure of determination of the quantum efficiency of luminescence of Mn²⁺ ions in the Zn₁₋xBexMnySe crystals. The method is based on the photoacoustic spectroscopy approach. In the paper, the experimental spectra of absorbance, transmission, absorption and photoacoustic spectra of the samples are presented and analyzed from the point of view of the possibility of determination of the quantum efficiency of Mn²⁺ ion luminescence at room temperature. It was determined experimentally that in the investigated crystals the quantum efficiency of luminescence in the Mn²⁺ ions is about 35%, 40%, 32% for the absorption peaks at 430 nm, 470 nm, and 510 nm, respectively, for Zn₀.₇₅Be₀.₂Mn₀.₀₅Se crystal.
8
Content available remote Numerical analysis of absorption and transmission photoacoustic spectra of silicon samples with differently treated surfaces
Maliński M., Chrobak Ł.
Opto-Electronics Review
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2011
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Vol. 19, No. 1
46-50
EN
This paper presents results of the photoacoustic (PA) spectral studies, of a series of silicon samples with differently prepared surfaces, in two PA experimental configurations, so-called, absorption and transmission ones. The PA amplitude spectra of the samples indicated existence of the damaged surface layers. In the paper, the two layer mathematical models of a sample with a damaged surface layer that were used for numerical interpretation of the amplitude PA spectra of the investigated samples, are presented and discussed.
9
Content available Photoacoustic diagnostics of inhomogeneous gyrotropic materials with internal stress using Bessel light beams
Mityurich G., Aleksiejuk M., Ranachowski P., Pelivanov I., Serdyukov A.
Archives of Metallurgy and Materials
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2011
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Vol. 56, iss. 4
1235-1242
EN
This paper considers the investigation of photoacoustic transformation in naturally-gyrotropic and magnetoactive crystals, with internal stress under sound excitation in different modes by Bessel light beams (BLB). In the range of high modulation frequencies (? > 1 MHz), the dependence of the photoacoustic response amplitude on the radial coordinate ? exhibits resonant phenomenon, which can be used to increase the resolution of photoacoustic spectroscopy for media with internal stresses. The expressions for amplitudes of photoacoustic signals in strained crystalline samples were obtained under different boundary conditions, taking into account the dependence of the thermoelastic coupling coefficient on the initial strain in the sample. It was showed that a resonant increase in the amplitude signal is related to the dependence on the geometric parameters of the sample-piezoelectric transducer system, the values of Murnagan constants, the mode composition of the Bessel light beam, and its amplitude modulation frequency.
PL
W pracy przedstawiono wyniki badań transformacji fotoakustycznej poprzez dźwięk generowany laserowymi wiązkami Bessela o różnych modach w kryształach naturalnie żyrotropowych i magnetoaktywnych, z wewnętrznymi naprężeniami. Stwierdzono, że w zakresie modulacji o wysokiej czestotliwosci ( > 1 MHz), zależność amplitudy odpowiedzi fotoakustycznej od radialnej współrzędnej wykazuje efekt rezonansowy. Efekt ten może być wykorzystany do podwyższenia rozdzielczości spektroskopii fotoakustycznej w ośrodkach z wewnętrznymi naprężeniami. Otrzymano wyrażenia na amplitudy sygnałów fotoakustycznych w próbkach krystalicznych z wewnętrznymi naprężeniami, przy różnych warunkach brzegowych. Brano przy tym pod uwagę zalezność współczynnika sprzężenia termoplastycznego od wewnętrznych naprężeń w próbce. Wykazano, że rezonansowy wzrost amplitudy sygnału jest zależny od geometrycznych parametrów układu próbka – przetwornik piezoelektryczny, wartości stałych Murnagana, modów wiązki Bessela i częstotliwości modulacji.
10
Content available Nieniszcząca spektroskopia fotoakustyczna w zastosowaniu do wyznaczania wydajności luminescencji jonów Mn2+ w kryształach mieszanych Zn1-x-yBexMnySe
Maliński M. A., Chrobak Ł. B.
Zeszyty Naukowe Wydziału Elektroniki i Informatyki Politechniki Koszalińskiej
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2010
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Nr 2
5--13
PL
Artykuł ten przedstawia zastosowanie nieniszczącej spektroskopii fotoakustycznej do wyznaczani wydajności kwantowej i energetycznej luminescecji jonów Mn2+ w kryształach Zn1-x-yBexMnySe.
EN
This paper is to present the application of the nondestructive photoacoustic spectroscopy method of determination of the quantum and energy efficiencies of luminescence of Mn2+ ions in the Zn1-x-yBexMnySe crystals.
11
Content available remote Influence of internal reflections of light on spectral characteristics of photoacoustic signal
Maliński M.
Opto-Electronics Review
|
2010
|
Vol. 18, No. 4
474-477
EN
The aim of this paper is to present the formula, and its derivation, for a photoacoustic (PA) signal in the front configuration in the case when the effect of multiple reflections of light in a sample is taken into account. The formula derived in the paper was next used for theoretical investigations of the influence of multiple reflections of light on series of PA spectral characteristics.
12
Content available Klasy odczynu i kategorie agronomiczne gleb a ich widma fotoakustyczne
Żurawska A., Rochowski P., Szurkowski J.
Inżynieria Rolnicza
|
2010
|
R. 14, nr 4
319-326
PL
W prezentowanej pracy wykorzystaliśmy spektroskopię fotoakustyczną do oceny możliwości rozróżnienia, przy jej pomocy, gleb należących do różnych klas odczynu. Do pomiarów zestawiliśmy klasyczny spektrometr fotoakustyczny z wysokociśnieniową lampą ksenonową jako źródłem światła, oraz zamkniętą komorą pomiarową. Otrzymane rezultaty wskazują na możliwość wykorzystania spektroskopii fotoakustycznej zarówno do badania składu chemicznego gleby, jak i przynależności do określonej kategorii agronomicznej.
EN
In this work, we used photoacoustic spectroscopy for evaluation of the possibility of distinguishing between soils belonging to different reaction classes by means of this technology. For our measurements we used a classic photoacoustic spectrometer together with a high-pressure xenon lamp as a light source and a closed measuring chamber. The received results indicate the possibility of use of photoacoustic spectroscopy for examining the chemical constitution of soil as well as its affinity to a certain agronomical category.
13
Content available Próba oceny dynamiki uwalniania wody z gleby przy pomocy spektroskopii fotoakustycznej
Żurawska A., Rochowski P., Szurkowski J.
Inżynieria Rolnicza
|
2009
|
R. 13, nr 5
329-335
PL
W prezentowanej pracy próbowaliśmy zastosować spektroskopię fotoakustyczną do oceny szybkości parowania (ewaporacji) gleby. W pomiarach wykorzystaliśmy aparaturę z dwoma wiązkami światła. Jedna z wiązek oświetlała próbki gleby silnym strumieniem światła niemodulowanego a druga z wiązek, o natężeniu ponad stukrotnie mniejszym, monitorowała zmiany zachodzące w badanych próbkach. Otrzymane rezultaty wskazują na możliwość wykorzystania spektroskopii fotoakustycznej nie tylko do oceny prędkości parowania gleby, lecz również w pomiarach zmian parametrów cieplnych jej wierzchnich warstw.
EN
In presented paper we have attempted to use photoacoustic spectroscopy to assess soil evaporation rate. We used equipment with two light beams in the measurements. One of the beams was illuminating soil samples with strong stream of non-modulated light and the second beam, with over one hundred times lower intensity, was monitoring changes proceeding in the tested samples. Obtained results indicate possibility to use photoacoustic spectroscopy not only for assessing soil evaporation rate, but also for measurements of changes in thermal parameters of its top layers.
14
Content available remote Carbon dioxide detection using NIR diode laser based wavelength modulation photoacoustic spectroscopy
Li J., Liu K., Zhang W., Chen W., Gao X.
Optica Applicata
|
2008
|
Vol. 38, nr 2
341-352
EN
A photoacoustic sensor using a laser diode emitting near 1573 nm in combination with a dual-microphone resonant photoacoustic cell has been developed for carbon dioxide trace gas analysis at atmospheric pressure. Wavelength-modulation scheme and 1f detection for CO2 concentration measurements in Ar are demonstrated. The noise equivalent absorption sensitivity of NEAS(1? ) = 1.01×10-8 Wcm-1/Hz1/2, corresponding to a detection limit of 30 parts in 106 by volume (ppmv) for a 100 s integration time and 4.5 mW average laser power. The photoacoustic response of CO2 dependence on the buffer gases with different mixture ratio of Ar and N2 was investigated. Finally, the possibility to make use of the sensor for measurements of ambient CO2 is also presented.
15
Investigations of chromium (III and VI) ions sorption on sir by using photoacoustic method
Wójcik G., Hubicki Z., Ryczkowski J.
Molecular and Quantum Acoustics
|
2008
|
Vol. 29
187-192
EN
Chromium is a major pollutant for the environment, usually as a result of some industrial pollution. Chromium is used in various industries such as metallurgical (steel, ferrous and nonferrous alloys), refractories (chrome and chromemagnesite), and chemical (pigments, electroplating, tanning). For this reason, significant amounts of chromium pass into the environment and cause adverse ecological effects. In the present paper the investigations of solvent impregnated resin (SIR) preparation was conducted. Photoacoustic (PAS) and diffuse reflectance spectroscopy (DRS) spectra were recorded for the prepared solvent impregnated resin. Photoacoustic spectra in the infrared area allow to distinguish the differences between the sorbent applied before and after the impregnation process. Impregnation of resin is a result of physical sorption of Aliquat 336 on macroporous Amberlite XAD 16.
16
Content available remote From magnetic fluids up to complex biocompatible nanosized magnetic systems
Morais P.C.
Bulletin of the Polish Academy of Sciences. Technical Sciences
|
2008
|
Vol. 56, nr 3
254-262
EN
The paper presents magnetic fluid as an excellent material platform for producing more complex magnetic drug delivery systems. In addition, the paper discusses the nanoparticle morphological (electron microscopy) and structural (X-ray diffraction) characterizations. Mössbauer spectroscopy and photoacoustic spectroscopy are revisited as key tools in the characterization of the magnetic core and diamagnetic shell of the magnetic nanoparticle, respectively.
17
Spektroskopia fotoakustyczna w podczerwieni
Ryczkowski J.
LAB Laboratoria, Aparatura, Badania
|
2007
|
R. 12, nr 6
6-10
18
Content available remote FT-IR/PAS w badaniu powierzchni adsorbentów i katalizatorów
Ryczkowski J.
Przemysł Chemiczny
|
2006
|
T. 85, nr 8-9
744-747
PL
Przedstawiono ogólne podstawy spektroskopii fotoakustycznej, ze szczególnym uwzględnieniem zastosowania tej techniki badawczej w zakresie podczerwieni. W oparciu o cytowaną literaturę wskazano możliwości jej wykorzystania do charakterystyki powierzchni adsorbentów i katalizatorów
EN
A review with 67 refs. covering PAS principles and possible FT-IR/PAS surface study applns.
19
Content available remote The linewidths and pintegrated intensities of the d-d transitions in photoacoustic spectra of polyamine copper(II) complexes
Guskos N., Typek J., Papadopoulos G. J., Maryniak M., Aidinis K.
Materials Science Poland
|
2005
|
Vol. 23, No. 4
955--960
EN
Photoacoustic spectra of the d-d transitions for three different series of copper(II) complexes of spermidines Spn (Spn323, Spn333, Spn343), Spm (Spm323, Spm333, Spm343) and Spc (Spc323, Spc333) have been investigated. Replacements of distant atoms, the presence or absence of water molecule in the structure, the kind of ligands surrounding the metal(II) ions have a strong influence on the crystal field splitting and the intensities of the non-radiative transitions. Non-radiative processes are involved in important mechanisms of the dynamic interactions between the electrons and the lattice. Studies of the intensities of the non-radiative transitions provide a very important data for the thermodynamic states of these systems. Photoacoustic absorption band of the d-d transitions could be decomposed into three lines (due to the crystal field splitting) with different intensities, positions and linewidths. The integrated intensities may yield information about the number of non-radiative processes, while the linewidths about the mechanisms of the relaxation processes.
20
Content available remote Photoacoustic study of a new neodymium(III) hydrazone complex
Guskos N., Paschalidis D. G., Majszczyk J., Typek J., Maryniak M.
Materials Science Poland
|
2005
|
Vol. 23, No. 4
1029--1034
EN
The neodymium(III) hydrazone complex [Nd(DBH)2(NO3)3] has been synthesized and characterized using microanalysis and IR spectroscopy. High-resolution photoacoustic spectrometry has been applied for studying the complex. The obtained photoacoustic spectrum has been analysed and compared to a similar [Nd(PicBH)2(NO3)2]NO3 complex. The intensities of the f-f transitions in the photoacoustic spectrum of Nd(DBH)2(NO3)3 were two times greater than for the [Nd(PicBH)2(NO3)2]NO3 complex.
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