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Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications

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A special issue of Applied Sciences (ISSN 2076-3417). This special issue belongs to the section "Optics and Lasers".

Deadline for manuscript submissions: closed (31 August 2021) | Viewed by 37061

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Special Issue Editors

Dr. Steven Wagner

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Guest Editor

Reactive Flows and Diagnostics, Technical University of Darmstadt, Otto-Berndt-Straße 3, 64287 Darmstadt, Germany
Interests: robust sensing; high temperature process diagnostics; combustion diagnostics; exhaust diagnostics; diode laser; absorption spectroscopy

Dr. Florian Schmidt

E-Mail Website
Guest Editor

Department of Applied Physics and Electronics, Umeå University, Umeå, Sweden
Interests: laser spectroscopy; TDLAS sensing; combustion diagnostics; thermochemical biomass conversion; medical diagnostics; breath gas analysis

Special Issue Information

Dear Colleagues,

After some decades of the development of Diode Laser Spectroscopy from a promising method for laboratory diagnostics to a versatile tool for sensing applications in harsh environments, the method still is evolving further. The growth of many different techniques based on diode lasers in combination with spectroscopic methods, such as direct and wavelength modulation absorption, cavity-enhanced absorption and photoacoustic spectroscopy, illustrates the variety of questions that can be addressed. There are already numerous mature devices and turn-key-systems available commercially. However, they are covering only a small fraction of applications, where the process of interest is accessible by optical diagnostics.

In this Special Issue, we invite submissions on the use of state-of-the-art Diode Laser Spectroscopy for robust sensing in a wide field, from fundamental sciences, environmental physics and biomedical monitoring to its utilization in harsh industrial conditions. Original work highlighting the latest research and technical development is encouraged. Contributions should be focused on the scientific and practical challenges of implementing Diode Laser Spectroscopy, as well as on novel ideas to increase the robustness of the method for monitoring processes and investigating phenomena. Review papers are welcome.

Dr. Steven Wagner
Dr. Florian Schmidt
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Applied Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

Diode Laser
Absorption
Emission
Photoacoustic
Spectroscopy
Robust Sensing
Process Monitoring

Related Special Issue

Diode Lasers: Materials, Devices and Application in Applied Sciences

Published Papers (14 papers)

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Research

11 pages, 5203 KiB

Open AccessFeature PaperArticle

Multiparameter Determination of Thin Liquid Urea-Water Films

by Sani van der Kley, Gabriele Goet, Anna Schmidt, Valentina Einspieler and Steven Wagner

Appl. Sci. 2021, 11(19), 8925; https://0-doi-org.brum.beds.ac.uk/10.3390/app11198925 - 24 Sep 2021

Cited by 1 | Viewed by 1489

Abstract

In this work, wavelengths were determined for the robust and simultaneous measurement of film thickness, urea concentration and fluid temperature. Film parameters such as film thickness, film temperature and the composition of the film are typically dynamically and interdependently changing. To gain knowledge of these quantities, a measurement method is required that offers a high temporal resolution while being non-intrusive so as to not disturb the film as well as the process conditions. We propose the extension of the FMLAS method, which was previously validated for the film thickness measurement of thin liquid films, to determine temperatures and concentrations using an adapted evaluation approach. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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14 pages, 1509 KiB

Open AccessFeature PaperArticle

Potassium Release from Biomass Particles during Combustion—Real-Time In Situ TDLAS Detection and Numerical Simulation

by Zhechao Qu, Hesameddin Fatehi and Florian M. Schmidt

Appl. Sci. 2021, 11(19), 8887; https://0-doi-org.brum.beds.ac.uk/10.3390/app11198887 - 24 Sep 2021

Cited by 10 | Viewed by 1824

Abstract

Potassium (K) is one of the main and most hazardous trace species released to the gas-phase during thermochemical conversion of biomass. Accurate experimental data and models of K release are needed to better understand the chemistry involved. Tunable diode laser absorption spectroscopy (TDLAS) is used for simultaneous real-time in situ measurements of gas-phase atomic K, water (H₂O) and gas temperature in the vicinity (boundary layer) of biomass particles during combustion in a laboratory single-particle reactor. Atomic K is detected in a wide dynamic range, including optically thick conditions, using direct absorption spectroscopy at the wavelength of 770 nm, while H₂O and temperature are determined by calibration-free scanned wavelength modulation spectroscopy at 1398 nm. The high accuracy and repeatability of the setup allows to distinguish measurements with varying initial particle mass, laser beam height above the particle and fuel type. Four types of biomass with different ash composition are investigated: softwood, Salix, Miscanthus and wheat straw. For Salix and wheat straw, the K release behaviour is, for the first time, compared to a detailed numerical particle model taking into account the interaction between K/S/Cl composition in the particle ash. A good agreement is achieved between the measured and calculated time-resolved atomic K concentrations for the devolatilization phase of the biomass particles. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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13 pages, 3876 KiB

Open AccessArticle

Laser-Based, Optical, and Traditional Diagnostics of NO and Temperature in 400 kW Pilot-Scale Furnace

by Alexey Sepman, Christian Fredriksson, Yngve Ögren and Henrik Wiinikka

Appl. Sci. 2021, 11(15), 7048; https://0-doi-org.brum.beds.ac.uk/10.3390/app11157048 - 30 Jul 2021

Cited by 4 | Viewed by 1835

Abstract

A fast sensor for simultaneous high temperature (above 800 K) diagnostics of nitrogen oxide (NO) concentration and gas temperature (T) based on the spectral fitting of low-resolution NO UV absorption near 226 nm was applied in pilot-scale LKAB’s Experimental Combustion Furnace (ECF). The experiments were performed in plasma and/or fuel preheated air at temperatures up to 1550 K, which is about 200 K higher than the maximal temperature used for the validation of the developed UV NO sensor previously. The UV absorption NO and T measurements are compared with NO probe and temperature measurements via suction pyrometry and tuneable diode laser absorption (TDL) using H₂O transitions at 1398 nm, respectively. The agreement between the NO UV and NO probe measurements was better than 15%. There is also a good agreement between the temperatures obtained using laser-based, optical, and suction pyrometer measurements. Comparison of the TDL H₂O measurements with the calculated H₂O concentrations demonstrated an excellent agreement and confirms the accuracy of TDL H₂O measurements (better than 10%). The ability of the optical and laser techniques to resolve various variations in the process parameters is demonstrated. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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19 pages, 5561 KiB

Open AccessFeature PaperArticle

Experimental Investigation of AdBlue Film Formation in a Generic SCR Test Bench and Numerical Analysis Using LES

by Anna Schmidt, Matthias Bonarens, Ilia V. Roisman, Kaushal Nishad, Amsini Sadiki, Andreas Dreizler, Jeanette Hussong and Steven Wagner

Appl. Sci. 2021, 11(15), 6907; https://0-doi-org.brum.beds.ac.uk/10.3390/app11156907 - 27 Jul 2021

Cited by 10 | Viewed by 2705

Abstract

In this work, an experimental investigation of AdBlue film formation in a generic selective catalytic reduction (SCR) exhaust gas test bench is presented. AdBlue is injected into a generic SCR test bench resulting in liquid film formation on the lower wall of the channel. The thickness of this liquid film is measured using a film thickness sensor based on absorption spectroscopy. Simultaneously, the wall temperature at the measurement point is monitored, which allows for examining correlations between the evolution of the film thickness and the temperature of the wetted wall. The velocity of the airflow in the channel and the initial wall temperature are varied in the experiments. Correspondingly, the measurements are performed during different thermodynamic regimes, including liquid film deposition and boiling. Repeated measurements have also shown that the film thicknesses are reproducible with a standard deviation of 3.4 %. LES-based numerical simulations are compared to the experimental results of the film thickness during the early injection stage. Finally, a numerical analysis is performed to analyze the AdBlue droplet impingement and subsequent film-formation dynamics. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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10 pages, 1834 KiB

Open AccessArticle

Towards an Optical Gas Standard for Traceable Calibration-Free and Direct NO₂ Concentration Measurements

by Javis A. Nwaboh, Zhechao Qu, Olav Werhahn and Volker Ebert

Appl. Sci. 2021, 11(12), 5361; https://0-doi-org.brum.beds.ac.uk/10.3390/app11125361 - 09 Jun 2021

Cited by 5 | Viewed by 1988

Abstract

We report a direct tunable diode laser absorption spectroscopy (dTDLAS) instrument developed for NO₂ concentration measurements without chemical pre-conversion, operated as an Optical Gas Standard (OGS). An OGS is a dTDLAS instrument that can deliver gas species amount fractions (concentrations), without any previous or routine calibration, which are directly traceable to the international system of units (SI). Here, we report NO₂ amount fraction quantification in the range of 100–1000 µmol/mol to demonstrate the current capability of the instrument as an OGS for car exhaust gas application. Nitrogen dioxide amount fraction results delivered by the instrument are in good agreement with certified values of reference gas mixtures, validating the capability of the dTDLAS-OGS for calibration-free NO₂ measurements. As opposed to the standard reference method (SRM) based on chemiluminescence detection (CLD) where NO₂ is indirectly measured after conversion to NO, titration with O₃ and the detection of the resulting fluorescence, a dTDLAS-OGS instrument has the benefit of directly measuring NO₂ without distorting or delaying conversion processes. Therefore, it complements the SRM and can perform fast and traceable measurements, and side-by-side calibrations of other NO₂ gas analyzers operating in the field. The relative standard uncertainty of the NO₂ results reported in this paper is 5.1% (k = 1, which is dominated (98%) by the NO₂ line strength), the repeatability of the results at 982.6 µmol/mol is 0.1%, the response time of the instrument is 0.5 s, and the detection limit is 825 nmol/mol at a time resolution of 86 s. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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12 pages, 5481 KiB

Open AccessArticle

H₂O Collisional Broadening Coefficients at 1.37 µm and Their Temperature Dependence: A Metrology Approach

by Javis A. Nwaboh, Olav Werhahn and Volker Ebert

Appl. Sci. 2021, 11(12), 5341; https://0-doi-org.brum.beds.ac.uk/10.3390/app11125341 - 08 Jun 2021

Cited by 5 | Viewed by 2092

Abstract

We report self- and air collisional broadening coefficients for the H₂O line at 7299.43 cm⁻¹ and corresponding temperature coefficients for a temperature range spanning 293–573 K. New laser spectroscopic setups specifically designed for this purpose have been developed and are described. The line parameters reported here are in good agreement with those values reported in the HITRAN 2020 database, but the uncertainties have been reduced by factors of about 4, 1.3 and 4.4 for the self-broadening coefficient, air broadening coefficient and the temperature exponent of air broadening, respectively. Further, we combined our measurement approach with metrological data quality objectives, addressing the traceability of the results to the international system of units (SI) and evaluated the uncertainties following the guide to the expression of uncertainty in measurement (GUM). Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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12 pages, 3010 KiB

Open AccessArticle

A Dual-Gas Sensor Using Photoacoustic Spectroscopy Based on a Single Acoustic Resonator

by Yiming Jiang, Tie Zhang, Gaoxuan Wang and Sailing He

Appl. Sci. 2021, 11(11), 5224; https://0-doi-org.brum.beds.ac.uk/10.3390/app11115224 - 04 Jun 2021

Cited by 6 | Viewed by 2475

Abstract

A dual-gas photoacoustic spectroscopy (PAS) sensor based on wavelength modulation spectroscopy (WMS) was developed and experimentally demonstrated. Distributed feedback (DFB) laser diodes, emitting at 1512 and 1653 nm, were utilized as the excitation sources for the simultaneous measurement of NH₃ and CH₄, respectively. The PAS signal was excited by modulating the DFB laser at the first longitudinal resonant frequency of a cylindrical acoustic resonator. Absorption lines for NH₃ and CH₄ were simultaneously recorded during one frequency scan of the DFB lasers without using any optical switch. The interference of NH₃ and CH₄ on each other was investigated for accurate detection. The limits of detection (LoDs) of the PAS sensor for NH₃ and CH₄ for an integration time of 100 s were determined to be 0.1 and 0.3 ppm, respectively. The present PAS sensor provides a new scheme for multi-gas analysis with the advantages of cost-effectiveness, a simple structure and multi-wavelength operation. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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11 pages, 1850 KiB

Open AccessArticle

Measurements of N₂, CO₂, Ar, O₂ and Air Pressure Broadening Coefficients of the HCl P(5) Line in the 1–0 Band Using an Interband Cascade Laser

by Zhechao Qu, Javis A. Nwaboh, Gang Li, Olav Werhahn and Volker Ebert

Appl. Sci. 2021, 11(11), 5190; https://0-doi-org.brum.beds.ac.uk/10.3390/app11115190 - 03 Jun 2021

Cited by 5 | Viewed by 2601

Abstract

We determine the CO₂, N₂, Ar, O₂ and air pressure broadening coefficients of the H³⁵Cl P(5) absorption line at 2775.77 cm⁻¹ in the fundamental (1←0) band using a newly developed direct tunable diode laser absorption spectroscopy (dTDLAS)-based spectrometer employing a mid-IR interband cascade laser (ICL). For the first time, a reliable and consistent set of five different foreign pressure broadening coefficients for the same HCl P(5) line has been measured by a consistent metrological approach covering pressures from 100 to 600 hPa at temperatures of 294 and 295 K. The relative uncertainties of the stated CO₂, N₂, Ar, O₂ and Air pressure broadening coefficients are in 1–3% range. The results are compared to previously available literature data—two broadening coefficients have been improved in accuracy and two have been determined for the first time in the sub 1000 hPa pressure range. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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10 pages, 3627 KiB

Open AccessFeature PaperArticle

Towards a Fast, Open-Path Laser Hygrometer for Airborne Eddy Covariance Measurements

by Felix Witt, Javis Nwaboh, Henning Bohlius, Astrid Lampert and Volker Ebert

Appl. Sci. 2021, 11(11), 5189; https://0-doi-org.brum.beds.ac.uk/10.3390/app11115189 - 03 Jun 2021

Cited by 6 | Viewed by 2399

Abstract

Water vapor fluxes play a key role in the energy budget of the atmosphere, and better flux measurements are needed to improve our understanding of the formation of clouds and storms. Large-scale measurements of these fluxes are possible by employing the eddy correlation (EC) method from an aircraft. A hygrometer used for such measurements needs to deliver a temporal resolution of at least 10 Hz while reliably operating in the harsh conditions on the exterior of an aircraft. Here, we present a design concept for a calibration-free, first-principles, open-path dTDLAS hygrometer with a planar, circular and rotationally symmetric multipass cell with new, angled coupling optics. From our measurements, the uncertainty of the instrument is estimated to be below 4.5% (coverage factor k = 1). A static intercomparison between a dTDLAS prototype of the new optics setup and a traceable dew point mirror hygrometer was conducted and showed a systematic relative deviation of 2.6% with a maximal relative error of 2.2%. Combined with a precision of around 1 ppm

H_{2} O

at tropospheric conditions, the newly designed setup fulfills the static precision and accuracy requirements of the proposed airborne EC hygrometer. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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14 pages, 2934 KiB

Open AccessArticle

Measurement of Water Mole Fraction from Acoustically Levitated Pure Water and Protein Water Solution Droplets via Tunable Diode Laser Absorption Spectroscopy (TDLAS) at 1.37 µm

by Julian F. A. Perlitz, Heiko Broß and Stefan Will

Appl. Sci. 2021, 11(11), 5036; https://0-doi-org.brum.beds.ac.uk/10.3390/app11115036 - 29 May 2021

Cited by 8 | Viewed by 2915

Abstract

In order to understand the evaporation and particle formation processes of sprays in technical applications such as fuel injectors or drying processes in the food and pharmaceutical industries in detail, single droplet drying experiments, for example, acoustic levitation, are widely used as model experiments. We combined acoustic levitation and tunable diode laser absorption spectroscopy (TDLAS) to measure the absolute H₂O concentration in the exhaust gas of a levitation chamber to investigate drying and particle formation processes from single droplets of pure water and protein–water solutions. To that end, we designed and developed a non-invasive, calibration-free TDLAS-based hygrometer to analyze the 1.4 µm overtone band. To increase the detection range of the developed hygrometer and to track the complete drying process of protein solution droplets even after the critical point of drying, the absorption length was extended to a path length of 18 m using an astigmatic multipass cell of the Herriott type. The setup was validated by drying pure water droplets, resulting in a determination of the water mole fraction in a range from 73 ppm to 1314 ppm, with a single scan resolution of 1.7 ppm. For protein solution droplets, the entire drying process, even beyond the critical point of drying, can be tracked and the different phases of the drying process can be characterized at different drying temperatures. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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14 pages, 444 KiB

Open AccessArticle

Experimental Characterization of Flame Structure and Soot Volume Fraction of Premixed Kerosene Jet A-1 and Surrogate Flames

by Thomas von Langenthal, Matthias Martin Sentko, Sebastian Schulz, Björn Stelzner, Dimosthenis Trimis and Nikolaos Zarzalis

Appl. Sci. 2021, 11(11), 4796; https://0-doi-org.brum.beds.ac.uk/10.3390/app11114796 - 24 May 2021

Cited by 4 | Viewed by 2558

Abstract

Modeling the chemical reactions and soot processes in kerosene flames is important to support the design of future generations of low-emission aircraft engines. To develop and validate these models, detailed experimental data from model flames with well-defined boundary conditions are needed. Currently, only few data from experiments with real aircraft engine fuels are available. This paper presents measurements of temperature, species and soot volume fraction profiles in premixed, flat flames using Jet A-1 kerosene and a two-component surrogate blend. Measurements were performed using a combination of TDLAS, GC and laser extinction. The results show that the flame structure in terms of temperature and species profiles of the kerosene and surrogate flames are very similar but differ greatly in the resulting soot volume fractions. Furthermore, the study shows that the available chemical mechanisms can correctly predict the temperature profiles of the flames but show significant differences from the experimentally observed species profiles. The differences in the sooting tendency of the kerosene and the surrogate are further investigated using detailed chemical mechanisms. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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16 pages, 4328 KiB

Open AccessArticle

Measurement of Temperature and H₂O Concentration in Premixed CH₄/Air Flame Using Two Partially Overlapped H₂O Absorption Signals in the Near Infrared Region

by Sunghyun So, Nakwon Jeong, Aran Song, Jungho Hwang, Daehae Kim and Changyeop Lee

Appl. Sci. 2021, 11(8), 3701; https://0-doi-org.brum.beds.ac.uk/10.3390/app11083701 - 20 Apr 2021

Cited by 8 | Viewed by 2282

Abstract

It is important to monitor the temperature and H₂O concentration in a large combustion environment in order to improve combustion (and thermal) efficiency and reduce harmful combustion emissions. However, it is difficult to simultaneously measure both internal temperature and gas concentration in a large combustion system because of the harsh environment with rapid flow. In regard, tunable diode laser absorption spectroscopy, which has the advantages of non-intrusive, high-speed response, and in situ measurement, is highly attractive for measuring the concentration of a specific gas species in the combustion environment. In this study, two partially overlapped H₂O absorption signals were used in the tunable diode laser absorption spectroscopy (TDLAS) to measure the temperature and H₂O concentration in a premixed CH₄/air flame due to the wide selection of wavelengths with high temperature sensitivity and advantages where high frequency modulation can be applied. The wavelength regions of the two partially overlapped H₂O absorptions were 1.3492 and 1.34927 μm. The measured signals separated the multi-peak Voigt fitting. As a result, the temperature measured by TDLAS based on multi-peak Voigt fitting in the premixed CH₄/air flame was the highest at 1385.80 K for an equivalence ratio of 1.00. It also showed a similarity to those tendencies to the temperature measured by the corrected R-type T/C. In addition, the H₂O concentrations measured by TDLAS based on the total integrated absorbance area for various equivalent ratios were consistent with those calculated by the chemical equilibrium simulation. Additionally, the H₂O concentration measured at an equivalence ratio of 1.15 was the highest at 18.92%. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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21 pages, 3742 KiB

Open AccessArticle

Advances in High-Precision NO₂ Measurement by Quantum Cascade Laser Absorption Spectroscopy

by Nicolas Sobanski, Béla Tuzson, Philipp Scheidegger, Herbert Looser, André Kupferschmid, Maitane Iturrate, Céline Pascale, Christoph Hüglin and Lukas Emmenegger

Appl. Sci. 2021, 11(3), 1222; https://0-doi-org.brum.beds.ac.uk/10.3390/app11031222 - 29 Jan 2021

Cited by 6 | Viewed by 3363

Abstract

Nitrogen dioxide (NO

_{2}

) is a major tropospheric air pollutant. Its concentration in the atmosphere is most frequently monitored indirectly by chemiluminescence detection or using direct light absorption in the visible range. Both techniques are subject to known biases from other trace [...] Read more.

Nitrogen dioxide (NO

_{2}

_{2}

in the mid-infrared have been proposed as a promising alternative, but field deployments and comparisons with established techniques remain sparse. Here, we describe the development and validation of a quantum cascade laser-based spectrometer (QCLAS). It relies on a custom-made astigmatic multipass absorption cell and a recently developed low heat dissipation laser driving and a FPGA based data acquisition approach. We demonstrate a sub-pptv precision (1

σ

) for NO

_{2}

after 150 s integration time. The instrument performance in terms of long-term stability, linearity and field operation capability was assessed in the laboratory and during a two-week inter-comparison campaign at a suburban air pollution monitoring station. Four NO

_{2}

instruments corresponding to three different detection techniques (chemiluminescence detection (CLD), cavity-attenuated phase shift (CAPS) spectroscopy and QCLAS) were deployed after calibrating them with three different referencing methods: gas-phase titration of NO, dynamic high-concentration cylinder dilution and permeation. These measurements show that QCLAS is an attractive alternative for high-precision NO

_{2}

monitoring. Used in dual-laser configuration, its capabilities can be extended to NO, thus allowing for unambiguous quantification of nitrogen oxides (NO

_{x}

), which are of key importance in air quality assessments. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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18 pages, 3389 KiB

Open AccessArticle

Martian Multichannel Diode Laser Spectrometer (M-DLS) for In-Situ Atmospheric Composition Measurements on Mars Onboard ExoMars-2022 Landing Platform

by Alexander Rodin, Imant Vinogradov, Sergei Zenevich, Maxim Spiridonov, Iskander Gazizov, Viktor Kazakov, Viacheslav Meshcherinov, Ilya Golovin, Tatyana Kozlova, Yuri Lebedev, Svetlana Malashevich, Artem Nosov, Oksana Roste, Alla Venkstern, Artem Klimchuk, Vladimir Semenov, Viktor Barke, Georges Durry, Mélanie Ghysels-Dubois, Elena Tepteeva and Oleg Korablev Show full author list Hide full author list

Appl. Sci. 2020, 10(24), 8805; https://0-doi-org.brum.beds.ac.uk/10.3390/app10248805 - 09 Dec 2020

Cited by 4 | Viewed by 4417

Abstract

We present a concept of the Martian multichannel diode laser spectrometer (M-DLS) instrument, a part of the science payload onboard Kazachok landing platform in the framework of the ExoMars mission second stage. The instrument, a laser spectrometer operating in the mid-IR spectral range, is aimed at long-term monitoring of isotopic ratios in main Martian volatiles—carbon dioxide and water vapor—in the near-surface atmosphere. The M-DLS spectrometer utilizes the integrated cavity output spectroscopy (ICOS) technique to enhance an effective optical path length and combines high sensitivity and measurement accuracy with relatively simple and robust design. Provided proper compensation of systematic errors by data post-processing, retrievals of main isotopic ratios with relative accuracy of 1% to 3% are expected during at least one Martian year. Full article

(This article belongs to the Special Issue Diode Laser Spectroscopy – Robust Sensing for Environmental and Industrial Applications)

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