@article{MTMT:34552784,
	title = {The investigation of diesel soot emission using instrument combination of multi-wavelength photoacoustic spectroscopy and scanning mobility particle sizer},
	url = {https://m2.mtmt.hu/api/publication/34552784},
	author = {Ajtai, Tibor and Utry, Noémi and Pintér, Máté and Abdul, Rahman and Kurilla, Boldizsár and Sárossy, Gábor and Deák, László and Baladincz, Jenő and Raffai, Péter and Szabó, Gábor and Bozóki, Zoltán},
	doi = {10.1038/s41598-024-52832-8},
	journal-iso = {SCI REP},
	journal = {SCIENTIFIC REPORTS},
	volume = {14},
	unique-id = {34552784},
	issn = {2045-2322},
	abstract = {The parallel measurements of wavelength dependent optical absorption, particle number size distribution have made by a multi wavelength photoacoustic spectrometer (4λ-PAS) and scanning mobility particle sizer (SMPS) respectively at different modes of a diesel engine using two different types of fuel. The thermal evolution of the emission was also investigated using posterior temperature treatment of emission. The bimodal size distribution of emitted particles at a set reference temperature has been observed regardless of the applied fuel at idle. However, the emitted particulate assembly had lognormal size distribution falls into the accumulation mode at all other defined engine modes and both fuel types. The total number- and volume concentration (TNC and TVC) showed retrograde tendency with the increasing torque and rpm independently of the applied fuel types. The TNC values decreased up to 50% for both fuels with engine operation changes from idle engine mode(em#1) to low engine mode(em#2). With further increase in torque and rpm of engine, the change in TNC is negligible. On the other hand, the TVC remains more or less the same for idle to low engine mode transition and increased more than 60% for high mode (em#3) transition. The Optical Absorption Coefficient (OAC) values measured at the operational wavelengths of the 4λ-PAS instrument decreased at all wavelengths with increasing rpm and torque. The wavelength dependency quantified by Aerosol Ängström Exponent (AAE) was applied here for qualitative analysis of the carbonaceous emission and showed decreased values towards the higher engine speed and torque output of the engine. The proposed technique can be used as real-time, precise and accurate measurement of light absorption by DPM aerosols, which opens up novel possibilities for the volatility and thermal evolution investigation of diesel emissions.},
	year = {2024},
	eissn = {2045-2322},
	orcid-numbers = {Kurilla, Boldizsár/0000-0002-7109-3107; Szabó, Gábor/0000-0001-6756-4677}
}

@article{MTMT:34506400,
	title = {Compensation of composition variation-induced sensitivity changes in gas phase photoacoustics},
	url = {https://m2.mtmt.hu/api/publication/34506400},
	author = {Végh, Panna and Gulyás, G. and Huszár, Helga and Ajtai, Tibor and Szabó, Gábor and Szabó, Anna and Bozóki, Zoltán},
	doi = {10.1016/j.infrared.2023.105116},
	journal-iso = {INFRARED PHYS TECHN},
	journal = {INFRARED PHYSICS & TECHNOLOGY},
	volume = {137},
	unique-id = {34506400},
	issn = {1350-4495},
	abstract = {Infrared photoacoustic (PA) spectroscopy is a widely used technique to monitor trace gas concentration changes during industrial processes where the bulk composition may vary considerably. However, the PA signal is prone to changes in bulk composition, leading to relative uncertainties in measurements of up to 10%, due to the complex dependence of the sensitivity of a PA system (S) on the thermal and acoustic properties of the gas sample. A novel calibration and concentration calculation method is proposed to keep the relative accuracy of the PA measurements in the few percentages range even in case of large-scale composition variations. The main novelty of the proposed method is that it tackles the complex dependence of the PA system's sensitivity in a way that while it varies the resonance frequency of the calibration gas, it keeps the heat capacity ratio of calibration gases at a constant value. We prove that it determines the analyte's concentration with relative accuracy of about 1 %, even when the composition of the gas varies drastically. It rigorously compensates for the frequency and heat capacity ratio dependence of S and for the dependence of the half-width of the resonance curve of the PA cell on the thermal and acoustic properties of the gas. Although the reported demonstration measurements are executed in a relatively simple gas mixture, the proposed method has widespread applicability in high-precision monitoring. © 2024 The Authors},
	keywords = {Sensitivity analysis; CALIBRATION; uncertainty analysis; Gases; specific heat; photoacoustic spectroscopy; Photoacoustic effect; Acoustic properties; Photoacoustic systems; Photoacoustics; Bulk compositions; Gas phase; Relative accuracy; heat capacity ratio; heat capacity ratio; Gas-phases; Composition variation; Acoustics property; Novel calibration methodology; Novel calibration methodology; Calibration gas; Calibration methodologies},
	year = {2024},
	eissn = {1879-0275},
	orcid-numbers = {Szabó, Gábor/0000-0001-6756-4677}
}

@CONFERENCE{MTMT:34754831,
	title = {Felszín és légkör közötti ammónia és dinitrogén-oxid kicserélődés vizsgálata fotoakusztikus spektroszkópiával},
	url = {https://m2.mtmt.hu/api/publication/34754831},
	author = {Szabó, Anna and Gombi, Csilla and Király, Csaba and Horváth, László and Huszár, Helga and Szabó, Gábor and Bozóki, Zoltán},
	booktitle = {A Magyar Tudományos Akadémia Analítikai és Környezetkémiai Bizottságának 11. Környezetkémiai Szimpóziuma. (2023)},
	unique-id = {34754831},
	year = {2023},
	pages = {-},
	orcid-numbers = {Szabó, Gábor/0000-0001-6756-4677}
}

@misc{MTMT:34720564,
	title = {Soot selective size distribution measurement using PhotoAcoustic Spectroscopy (PAS). A demonstrative study},
	url = {https://m2.mtmt.hu/api/publication/34720564},
	author = {Hodovány, Szabolcs and Ajtai, Tibor and Martin, Schnaiter and Szabó, Gábor and Bozóki, Zoltán},
	unique-id = {34720564},
	year = {2023},
	orcid-numbers = {Szabó, Gábor/0000-0001-6756-4677}
}

@CONFERENCE{MTMT:34171639,
	title = {Application of a bi-directional ammonia exchange model for optimization of input parameters at a fertilized crop system; validation by flux measurements},
	url = {https://m2.mtmt.hu/api/publication/34171639},
	author = {Horváth, László and Huszár, Helga and Zoltán, Nagy and Pintér, Krisztina and Szabó, Anna and Takács, Tünde Mária and Péter, Torma and Tóth, Eszter and Weidinger, Tamás and Bozóki, Zoltán},
	booktitle = {EGU General Assembly 2023: Abstracts},
	doi = {10.5194/egusphere-egu23-5854},
	unique-id = {34171639},
	year = {2023},
	orcid-numbers = {Takács, Tünde Mária/0000-0002-2399-2415; Weidinger, Tamás/0000-0001-7500-6579}
}

@misc{MTMT:34146195,
	title = {Gázmintavételezés nélküli fotoakusztikus rendszerek légköri ammónia- és vízgőzfluxus mérésekhez},
	url = {https://m2.mtmt.hu/api/publication/34146195},
	author = {Szabó, Anna and Torma, Péter and Gombi, Csilla and Horváth, László and Huszár, Helga and Weidinger, Tamás and Szabó, Gábor and Bozóki, Zoltán},
	unique-id = {34146195},
	year = {2023},
	orcid-numbers = {Szabó, Gábor/0000-0001-6756-4677}
}

@CONFERENCE{MTMT:34145954,
	title = {Developing a method to estimate the ammonia loss from fertilized cropland and the part of soil emission recaptured by the canopy, applying field scale bidirectional models and flux measurements},
	url = {https://m2.mtmt.hu/api/publication/34145954},
	author = {László, Horváth and Csilla, Gombi and Huszár, Helga and Zoltán, Nagy and Pintér, Krisztina and Szabó, Anna and Takács, Tünde Mária and Péter, Torma and Tóth, Eszter and Tamás, Weidinger and Szabó, Gábor and Bozóki, Zoltán},
	booktitle = {EMS Annual Meeting Abstracts},
	doi = {10.5194/ems2023-145},
	unique-id = {34145954},
	year = {2023},
	orcid-numbers = {Takács, Tünde Mária/0000-0002-2399-2415; Szabó, Gábor/0000-0001-6756-4677}
}

@CONFERENCE{MTMT:33938284,
	title = {Application of open photoacoustic cell in an eddy covariance system for water vapor flux measurement},
	url = {https://m2.mtmt.hu/api/publication/33938284},
	author = {Torma, Péter and Weidinger, Tamás and Juhász, Viktor and Molnár, Bence and Horváth, László and Huszár, Helga and Bozóki, Zoltán},
	booktitle = {EGU General Assembly 2023: Abstracts},
	doi = {10.5194/egusphere-egu23-12898},
	unique-id = {33938284},
	year = {2023},
	orcid-numbers = {Torma, Péter/0000-0001-9282-6931; Weidinger, Tamás/0000-0001-7500-6579}
}

@article{MTMT:33804983,
	title = {Absorption based size characterisation of aerosol by using photoacoustic spectroscopy},
	url = {https://m2.mtmt.hu/api/publication/33804983},
	author = {Ajtai, Tibor and Hodovány, Szabolcs and Schnaiter, M. and Szabó, Gábor and Bozóki, Zoltán},
	doi = {10.1016/j.atmosenv.2023.119772},
	journal-iso = {ATMOS ENVIRON},
	journal = {ATMOSPHERIC ENVIRONMENT},
	volume = {304},
	unique-id = {33804983},
	issn = {1352-2310},
	abstract = {The size of the atmospheric soot is a critical parameter in many perspectives starting from climate impact through health relevance ended with air quality regulations. In this study, we propose a novel methodology for soot selective size measurement of atmospheric aerosol. The proposed method is based on the synergy of selectivity of the aerosol photoacoustic (PA) spectroscopy for highly absorbing atmospheric components and size dependency of the measured phase of the PA signal. The proposed experimental set-up is based on the instrument combination of 4λ-PAS and scanning mobility particle sizer (SMPS) in a closed loop arrangement. We experimentally demonstrated here, first that the PA phase of the photoacoustic signal depends on the characteristic size of the soot aerosol. In order to better understand the effect of morphology, nigrosine particles with spherical shape are also studied. The comparison of the measured data and the theoretical calculation is also investigated. Comparison of the theoretical simulation and the measured data shows increasing differences towards the higher size of the measured aerosol in all samples. We also demonstrated that the inherent system phase is independent of the phase shift related to particles. © 2023},
	keywords = {ABSORPTION; review; CARBON; aerosol; aerosol; MORPHOLOGY; nonhuman; size distribution; size distribution; particle size; soot; soot; photoacoustic spectroscopy; photoacoustic spectroscopy; Ultraviolet visible spectroscopy; BLACK CARBON; BLACK CARBON; BLACK CARBON; ATMOSPHERIC AEROSOLS; Air quality; Air quality; climate effect; Photoacoustic effect; Photoacoustic; SMPS; Scanning mobility particle sizer; size-distribution; Novel methodology; Photoacoustic signals; Climate impacts; Size characterization; Size measurements; Air quality regulations; Health relevances},
	year = {2023},
	eissn = {1873-2844},
	orcid-numbers = {Szabó, Gábor/0000-0001-6756-4677}
}

@article{MTMT:33702561,
	title = {Possible environmental applications of a recently developed ammonia isotope monitoring photoacoustic system},
	url = {https://m2.mtmt.hu/api/publication/33702561},
	author = {Ouma, Emily Awuor and Huszár, Helga and Horváth, László and Szabó, Gábor and Bozóki, Zoltán},
	doi = {10.28974/idojaras.2023.1.3},
	journal-iso = {IDŐJÁRÁS},
	journal = {IDŐJÁRÁS / QUARTERLY JOURNAL OF THE HUNGARIAN METEOROLOGICAL SERVICE},
	volume = {127},
	unique-id = {33702561},
	issn = {0324-6329},
	abstract = {Ammonia is one of the most significant environmental pollutants. Concentration measurements, identifying the sources and studying the transformations in the biosphere are essential, and they are the focus of many investigations. The near-infrared (≈1530 nm) photoacoustic method for simultaneous and selective determination of 14NH3/15NH3 isotopologues reported here can be suitable for monitoring these phenomena and processes. So far, the photoacoustic method has not been used for this kind of examination. The application of our measurement method makes it possible to eliminate the disadvantages of the previous measurement methods. The detection limit of the PA system is 0.14 ppm and 0.73 ppm for 14NH3 and 15NH3, respectively, which can be improved by orders of magnitude with further development of sampling and measurement techniques.},
	year = {2023},
	eissn = {0324-6329},
	pages = {43-53},
	orcid-numbers = {Ouma, Emily Awuor/0000-0003-2298-4998; Szabó, Gábor/0000-0001-6756-4677}
}