Journal articles: 'Environmental monitoring Air Fourier transform infrared spectroscopy'

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Yuan, Zhengyang, Jiayong Zhou, Cuncun Qian, Shizhong Wang, Juntao Zhao, and Hongqi Shi. "Status and inspiration on the development of the air monitoring system ANITA for European Space Agency." E3S Web of Conferences 237 (2021): 01014. http://dx.doi.org/10.1051/e3sconf/202123701014.

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This paper describes the technical characteristics and application status of ANITAII (Analysing Interferometer for Ambient Air), an atmospheric monitoring system currently used by ESA (European Space Agency), reveals the characteristics and advantages of FTIR (Fourier transform infrared spectroscopy) technology in multi-component gas monitoring, and analyzes the application prospect of FTIR technology in the field of environmental monitoring.

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Fathy, Alaa, Marie Le Pivert, Young Jai Kim, Mame Ousmane Ba, Mazen Erfan, Yasser M. Sabry, Diaa Khalil, Yamin Leprince-Wang, Tarik Bourouina, and Martine Gnambodoe-Capochichi. "Continuous Monitoring of Air Purification: A Study on Volatile Organic Compounds in a Gas Cell." Sensors 20, no. 3 (February 10, 2020): 934. http://dx.doi.org/10.3390/s20030934.

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Air pollution is one of the major environmental issues that humanity is facing. Considering Indoor Air Quality (IAQ), Volatile Organic Compounds (VOCs) are among the most harmful gases that need to be detected, but also need to be eliminated using air purification technologies. In this work, we tackle both problems simultaneously by introducing an experimental setup enabling continuous measurement of the VOCs by online absorption spectroscopy using a MEMS-based Fourier Transform infrared (FTIR) spectrometer, while those VOCs are continuously eliminated by continuous adsorption and photocatalysis, using zinc oxide nanowires (ZnO-NWs). The proposed setup enabled a preliminary study of the mechanisms involved in the purification process of acetone and toluene, taken as two different VOCs, also typical of those that can be found in tobacco smoke. Our experiments revealed very different behaviors for those two gases. An elimination ratio of 63% in 3 h was achieved for toluene, while it was only 14% for acetone under same conditions. Adsorption to the nanowires appears as the dominant mechanism for the acetone, while photocatalysis is dominant in case of the toluene.

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Kireche, Nora, Sébastien Rondot, Ferroudja Bitam-Megherbi, Omar Jbara, Mickael Gilliot, and Jean-Marc Patat. "Experimental study of polymethyl methacrylate: damage under corona discharge." European Physical Journal Applied Physics 82, no. 3 (June 2018): 31301. http://dx.doi.org/10.1051/epjap/2018180073.

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In high-voltage applications, insulators may be exposed to corona discharges during long periods. In this experimental work, corona discharge tests of different durations are carried out in air at atmospheric pressure on polymethyl methacrylate (PMMA) samples. The resulting surface degradation is studied with several techniques. The surface damages are observed with environmental scanning electron microscope and atomic force microscopy. The results show that electrical trees occur on the surface of material and their distribution depends on the corona discharge duration. The chemical changes on PMMA surface are analyzed by Fourier transform infrared spectroscopy and a chemical degradation mechanism is proposed. Evolution of surface resistivity with corona aging is also implemented by using a classical I(V) method. In addition, to study the dielectric behavior of PMMA, the monitoring of kinetics of the trapped charge under electron irradiation in a scanning electron microscope is performed. The charging ability of PMMA under electron irradiation and its time constant of charging decrease with electrical aging.

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Cursaru, Laura-Madalina, Ana-Maria Mocioiu, Ioan Albert Tudor, and Roxana Mioara Piticescu. "Hydrothermal Synthesis of Carbon Nanotubes-Polyaniline(CNT-PANI)Composites and Preliminary Electrochemical Characterization of CNT-PANI Coatings." Materiale Plastice 57, no. 3 (September 30, 2020): 238–48. http://dx.doi.org/10.37358/mp.20.3.5396.

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Heavy metals have a major contribution to biosphere pollution due to toxicity. The detection and monitoring of the environmental agents in soil, water and air is very important for the general health of humans and animals. It has been recently shown that electrochemical techniques such as differential pulse voltammetry (DPV) and square wave anodic stripping voltammetry (SWASV) using modified electrodes are very attractive methods for detecting heavy metals. The aim of this paper is to demonstrate the potential of hydrothermal process combined with electrochemical techniques to obtain modified electrodes based on functionalized carbon nanotubes (CNTs) and polyaniline (PANI) for metals detection. Commercial multi-walled carbon nanotubes (MWCNT) were functionalized by a mixture of HNO3/H2SO4 and further used for hydrothermal synthesis of CNT-PANI composites with different mass ratios. The resulted powders were analyzed by spectral (Fourier-Transform Infrared Spectroscopy) and thermal (Differential Scanning Calorimetry) methods, and then dispersed in a surfactant/electrolyte solution for preliminary electrochemical experiments (cyclic voltammetry, CV and DPV) to obtain modified electrodes. The influence of the CNT: PANI mass ratio and the synthesis time on the formation of composites with the desired structural and electrochemical properties were studied. It was found that CNT-PANI composite powder having mass ratio 1:4 and synthesis time 3h has the best structural and thermal characteristics and formed a weakly conductive film on the surface of the glassy carbon electrode. Preliminary electrochemical tests revealed the electroactive forms of polyaniline, through the presence of characteristic oxidation peaks but also reduction peaks, corresponding to reversible redox reactions, demonstrating that glassy carbon electrode has been electrochemically modified with CNT-PANI coatings. Further studies will be conducted to test the potential application of glassy carbon electrode modified with CNT-PANI coatings as electrochemical sensor for heavy metals detection.

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Haus, R., K. Schäfer, W. Bautzer, J. Heland, H. Mosebach, H. Bittner, and T. Eisenmann. "Mobile Fourier-transform infrared spectroscopy monitoring of air pollution." Applied Optics 33, no. 24 (August 20, 1994): 5682. http://dx.doi.org/10.1364/ao.33.005682.

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Lavorante, André F., Salvador Garrigues, Boaventura F. Reis, Ángel Morales-Rubio, and Miguel de la Guardia. "Monitoring of the smoking process by multicommutation Fourier Transform Infrared spectroscopy." Analytica Chimica Acta 593, no. 1 (June 2007): 39–45. http://dx.doi.org/10.1016/j.aca.2007.04.051.

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Khaustova, Svetlana, Maxim Shkurnikov, Evgeny Tonevitsky, Viacheslav Artyushenko, and Alexander Tonevitsky. "Noninvasive biochemical monitoring of physiological stress by Fourier transform infrared saliva spectroscopy." Analyst 135, no. 12 (2010): 3183. http://dx.doi.org/10.1039/c0an00529k.

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Pui, Aurel, Catalin Tanase, Danut-Gabriel Cozma, and Tiberius Balaes. "ASSESSMENT OF MACROMYCETES USING FOURIER TRANSFORM INFRARED SPECTROSCOPY AND CHEMOMETRICS." Environmental Engineering and Management Journal 12, no. 3 (2013): 527–34. http://dx.doi.org/10.30638/eemj.2013.065.

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Sebih, Zakia, Serge Bourbigot, Rene Delobel, and Franck Poutch. "Quantitative analysis of automotive exhaust gas by Fourier Transform Infrared spectroscopy." International Journal of Environmental Technology and Management 13, no. 2 (2010): 188. http://dx.doi.org/10.1504/ijetm.2010.034301.

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Griffith, D. W. T., N. M. Deutscher, C. G. R. Caldow, G. Kettlewell, M. Riggenbach, and S. Hammer. "A Fourier transform infrared trace gas analyser for atmospheric applications." Atmospheric Measurement Techniques Discussions 5, no. 3 (May 29, 2012): 3717–69. http://dx.doi.org/10.5194/amtd-5-3717-2012.

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Abstract. Concern in recent decades about human impacts on Earth's climate has led to the need for improved and expanded measurement capabilities for greenhouse gases in the atmosphere. In this paper we describe in detail an in situ trace gas analyser based on Fourier Transform Infrared (FTIR) spectroscopy that is capable of simultaneous and continuous measurements of carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), nitrous oxide (N2O) and 13C in CO2 in air with high precision and accuracy. Stable water isotopes can also be measured in undried airstreams. The analyser is automated and allows unattended operation with minimal operator intervention. Precision and accuracy meet and exceed the compatibility targets set by the World Meteorological Organisation – Global Atmosphere Watch Programme for baseline measurements in the unpolluted troposphere for all species except 13C in CO2. The analyser is mobile and well suited to fixed sites, tower measurements, mobile platforms and campaign-based measurements. The isotopic specificity of the optically-based technique and analysis allows application of the analyser in isotopic tracer experiments, for example 13C in CO2 and 15N in N2O. We review a number of applications illustrating use of the analyser in clean air monitoring, micrometeorological flux and tower measurements, mobile measurements on a train, and soil flux chamber measurements.

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LI-SHI, YING, STEVEN P. LEVINE, CHRISTOPHER R. STRANG, and WILLIAM F. HERGET. "Fourier Transform Infrared (FTIR) Spectroscopy for Monitoring Airborne Gases and Vapors of Industrial Hygiene Concern." American Industrial Hygiene Association Journal 50, no. 7 (July 1989): 354–59. http://dx.doi.org/10.1080/15298668991374796.

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Kroutil, R. T., R. J. Combs, R. B. Knapp, and G. W. Small. "Automated Detection of Acetone, Methyl Ethyl Ketone, and Sulfur Hexafluoride by Direct Analysis of Fourier Transform Infrared Interferograms." Applied Spectroscopy 48, no. 6 (June 1994): 724–32. http://dx.doi.org/10.1366/000370294774368901.

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The lack of a valid background reference spectrum for many Fourier transform infrared (FT-IR) spectrometric open-air monitoring applications limits the ability to perform quantitative measurements. Direct interferogram analysis suppresses the broad-band detector envelope and maintains the spectral signature of interest to circumvent this limitation. The background suppression approach uses a combination of interferogram segment selection, digital filtering, and pattern discrimination techniques. The spectral band location, width, and contour of the vapor determine the parameters necessary for background suppression. Interferogram segment selection relies principally on the spectral bandwidth. Digital filter design employs inputs of both spectral band location and width. Pattern discrimination methods consider the variation in the spectral band contour with band intensity. FT-IR spectrometer measurements from both laboratory and open-air trials demonstrate the utility of the background suppression approach with analytes of acetone, methyl ethyl ketone (MEK), and sulfur hexafluoride (SF6).

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Griffith, D. W. T., N. M. Deutscher, C. Caldow, G. Kettlewell, M. Riggenbach, and S. Hammer. "A Fourier transform infrared trace gas and isotope analyser for atmospheric applications." Atmospheric Measurement Techniques 5, no. 10 (October 24, 2012): 2481–98. http://dx.doi.org/10.5194/amt-5-2481-2012.

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Abstract. Concern in recent decades about human impacts on Earth's climate has led to the need for improved and expanded measurement capabilities of greenhouse gases in the atmosphere. In this paper we describe in detail an in situ trace gas analyser based on Fourier Transform Infrared (FTIR) spectroscopy that is capable of simultaneous and continuous measurements of carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), nitrous oxide (N2O) and 13C in CO2 in air with high precision. High accuracy is established by reference to measurements of standard reference gases. Stable water isotopes can also be measured in undried airstreams. The analyser is automated and allows unattended operation with minimal operator intervention. Precision and accuracy meet and exceed the compatibility targets set by the World Meteorological Organisation – Global Atmosphere Watch for baseline measurements in the unpolluted troposphere for all species except 13C in CO2. The analyser is mobile and well suited to fixed sites, tower measurements, mobile platforms and campaign-based measurements. The isotopic specificity of the optically-based technique and analysis allows its application in isotopic tracer experiments, for example in tracing variations of 13C in CO2 and 15N in N2O. We review a number of applications illustrating use of the analyser in clean air monitoring, micrometeorological flux and tower measurements, mobile measurements on a train, and soil flux chamber measurements.

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García-González, Diego L., and Frederik R. Van De Voort. "A Novel Wire Mesh “Cell” for Studying Lipid Oxidative Processes by Fourier Transform Infrared Spectroscopy." Applied Spectroscopy 63, no. 5 (May 2009): 518–27. http://dx.doi.org/10.1366/000370209788346995.

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A novel infrared (IR) sample handling accessory has been developed to monitor and study oxidation processes of edible oils under moderate temperature conditions by Fourier transform infrared (FT-IR) spectroscopy. A reusable stainless steel mesh IR “cell” was designed and evaluated from the standpoint of mesh size, transmission characteristics, its ability to entrap oil, and techniques to apply sample and normalize path length so as to obtain good quality, reproducible spectra. The concept is to entrap oil within the mesh by means of its inherent surface tension and to take advantage of the high surface area provided by the mesh to facilitate rapid oxidation of the oil by air at ambient or slightly elevated temperatures without having to resort to more extreme temperature conditions to track oxidative changes in real time. Changes taking place in canola oil at room temperature, in the dark and exposed to light, as well as at 50 °C are presented to illustrate the performance of the cell in monitoring oxidative changes in real time (e.g., formation of hydroperoxides, loss of cis and formation of trans double bonds). The mesh cell should be useful for comparing the relative performance of antioxidants as well as evaluating the oxidative stability of oils, among other applications.

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Johansen, Ib-Rune, Glenn Terje Lines, Atle Honne, and Tonje Midtgaard. "Calibration of an FT-IR Spectrometer for Ambient Air Monitoring Using PLS." Applied Spectroscopy 51, no. 10 (October 1997): 1540–46. http://dx.doi.org/10.1366/0003702971939073.

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The objective of this work has been to develop a robust calibration method for simultaneous multigas detection with a Fourier transform infrared (FT-IR) system. Calibration models for the identification and quantification of 23 gases in the presence of high concentrations of background gases such as water vapor, carbon dioxide, and methane have been obtained for an FT-IR instrument with 0.7-cm−1 resolution. The calibration models have been tested on a breadboard instrument for trace gas measurement in manned space missions. The results show that FT-IR combined with multivariate methods such as partial least-squares (PLS) and proper pretreatment of the infrared spectra used in calibration is well suited for this purpose. A procedure for baseline drift compensation has been introduced to make the system insensitive to baseline drift and variations in transmittance. This baseline drift compensation also reduces the need for background measurements. Further, a procedure for incorporating a priori information about the instrument signal-to-noise ratio (SNR) and the absorption strength of interfering absorption lines has been developed. Indoor air monitoring and industrial process monitoring are other possible application areas for these techniques. Parts of this work have been performed in a project for the European Space Agency (ESA) in cooperation with Kayser-Threde GmbH and Daimler-Benz Aerospace, Dornier GmbH.

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Ogburn, Zachary L., and Frank Vogt. "Modeling Microalgal Biosediment Formation Based on Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Monitoring." Applied Spectroscopy 72, no. 3 (October 6, 2017): 366–77. http://dx.doi.org/10.1177/0003702817728070.

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With increasing amounts of anthropogenic pollutants being released into ecosystems, it becomes ever more important to understand their fate and interactions with living organisms. Microalgae play an important ecological role as they are ubiquitous in marine environments and sequester inorganic pollutants which they transform into organic biomass. Of particular interest in this study is their role as a sink for atmospheric CO2, a greenhouse gas, and nitrate, one cause of harmful algal blooms. Novel chemometric hard-modeling methodologies have been developed for interpreting phytoplankton’s chemical and physiological adaptations to changes in their growing environment. These methodologies will facilitate investigations of environmental impacts of anthropogenic pollutants on chemical and physiological properties of marine microalgae (here: Nannochloropsis oculata). It has been demonstrated that attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy can gain insights into both and this study only focuses on the latter. From time-series of spectra, the rate of microalgal biomass settling on top of a horizontal ATR element is derived which reflects several of phytoplankton’s physiological parameters such as growth rate, cell concentrations, cell size, and buoyancy. In order to assess environmental impacts on such parameters, microalgae cultures were grown under 25 different chemical scenarios covering 200–600 ppm atmospheric CO2 and 0.35–0.75 mM dissolved NO3−. After recording time-series of ATR FT-IR spectra, a multivariate curve resolution–alternating least squares (MCR-ALS) algorithm extracted spectroscopic and time profiles from each data set. From the time profiles, it was found that in the considered concentration ranges only NO3− has an impact on the cells’ physiological properties. In particular, the cultures’ growth rate has been influenced by the ambient chemical conditions. Thus, the presented spectroscopic + chemometric methodology enables investigating the link between chemical conditions in a marine ecosystem and their consequences for phytoplankton living in it.

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Chen, M. J., J. M. Duh, R. H. Shie, J. H. Weng, and H. T. Hsu. "Dynamic real-time monitoring of chloroform in an indoor swimming pool air using open-path Fourier transform infrared spectroscopy." Indoor Air 26, no. 3 (May 15, 2015): 457–67. http://dx.doi.org/10.1111/ina.12215.

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Powell, G. L., M. Milosevic, J. Lucania, and N. J. Harrick. "The Spectropus™ System: Remote Sampling Accessories for Reflectance, Emission, and Transmission Analysis Using Fourier Transform Infrared Spectroscopy." Applied Spectroscopy 46, no. 1 (January 1992): 111–25. http://dx.doi.org/10.1366/0003702924444272.

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The Spectropus™ system,‡ a versatile optical sampling system for performing infrared spectroscopic analyses on remotely located samples with little regard to their size and with spectral quality and sampling rates comparable to, or better than, those achievable with spectrometer sample compartment accessories, is described. The Spectropus™ uses a “glass-tube beam-line” optical transfer system for delivering the collimated beam of an FT-IR spectrometer to one of several dedicated accessories, complete with its own detector, that may be located several meters distance from the spectrometer. The accessories include the barrel ellipsoid diffuse reflectance and emission accessory, the grazing-incidence external reflection accessory, and the gas analysis accessory. One system described here supports up to four accessories in laboratory air and another supports two accessories in two different glove boxes. Application examples include the monitoring of the formation of LiOH and LiOD on LiH and LiD in glove boxes as a result of moisture corrosion; the analysis of ink stains on paper; the analysis of inks, parylene films, and oil stains on metals; the analysis, with monolayer resolution, of oxides on aluminum foil and on uranium being oxidized in air; the analysis of wood and of graphite-epoxy composites, including the rapid sequential determination of diffuse reflectance and emission spectra from one point on one sample; and sub-part-per-million gas analyses using an evacuated cell reference spectrum that is free of pressurization stress artifacts.

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Majder-Łopatka, Małgorzata, Wioletta Rogula-Kozłowska, and Wiktor Wąsik. "The application of stand-off infrared detection to identify air pollutants." E3S Web of Conferences 44 (2018): 00104. http://dx.doi.org/10.1051/e3sconf/20184400104.

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Fourier-transform infrared spectroscopy (FT-IR) enables the passive detection and identification of chemical agent clouds from distances. It can be used for the monitoring of large spaces and protection of industrial installations outside buildings. The aim of the study was show the possibilities and limitations of passive FT-IR. In studies done by the Faculty of Fire Safety Engineering at the Main School of Fire Service were used spectrometer RAPID (Remote Air Pollution Infrared Detector), Bruker Daltonics Company. Hazardous substances such as acetone, methanol, ammonia was identified on-line from several observation points at 25 m, 50 m and 75 m. The tests were carried out at various meteorological conditions. The results indicate that remote infrared detection allows detecting hazardous chemical agents in the atmosphere from a distance. Nevertheless, meteorological and terrain conditions have a big impact on the measurement results. During measurements, the detector indicated the presence of other substances. Moreover, it was found that under cloudy and windy weather, remote detection is not possible.

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Bauer, Bill, and Teri A. Floyd. "Monitoring of glucose in biological fluids by fourier-transform infrared spectrometry with a cylindrical internal reflectance cell." Analytica Chimica Acta 197 (1987): 295–301. http://dx.doi.org/10.1016/s0003-2670(00)84740-6.

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Ichwana, Ichwana, Zulkifli Nasution, and Agus Arip Munawar. "The Application of Fourier Transform Infrared Photoacoustics Spectroscopy (FTIR-PAS) for Rapid Soil Quality Evaluation." Rona Teknik Pertanian 10, no. 1 (April 1, 2017): 1–10. http://dx.doi.org/10.17969/rtp.v10i1.6984.

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Abstrak. Tanah merupakan media tumbuh tanaman dan berperan dalam menjaga keseimbangan alam. Evaluasi kualitas dan kesuburan tanah menjadi hal penting dan merupakan pekerjaan rutin pada crop management system. Untuk memonitor dan menentukan kualitas tanah, beberapa metode telah diterapkan. Akan tetapi, metode tersebut berbasis pengukuran laboratorium yang melibatkan bahan kimia, memerlukan waktu yang lama dan kurang efektif pada aplikasinya. Infrared spectroscopy muncul sebagai salah satu teknologi yang cepat, simultan dan ramah lingkungan untuk digunakan dalam evaluasi kualitas dan kesuburan tanah dengan memprediksi nutrisi tanah yang utama berupa C, N, P dan K. Spektrum transmisi infrared (IR) diakuisisi pada panjang gelombang 1000-2500 nm dengan menerapkan metode photo-acoustic spectroscopy (PAS). Pendekatan metode Least square-support vector machine regression (LS-SVM) digunakan untuk memprediksi parameter nutrisi tanah. Hasil studi menemukan bahwa parameter C dan N pada tanah dapat diprediksi dengan sempurna karena C-N mengalami stretching akibat serapan gelombang IR. Sedangkan unsur nutrisi lain seperti P, K, Mg, Ca, S dapat diprediksi dengan maksimum residual predictive deviation (RPD) index maksimum 1.9. Lebih lanjut, lempung tanah, air tanah, dan mikroba tanah kemungkinan dapat diklasifikasi dengan baik dengan metode IR-PAS dan bantuan metode klasifikasi least-square discriminant analysis (LS-DA) dan cluster analysis (CA). Berdasarkan hasil studi, dapat disimpulkan bahwa teknologi FTIR-PAS dapat digunakan untuk real-time monitoring kualitas dan kesuburan tanah. The Application of Fourier Transform Infrared Photoacoustics Spectroscopy (FTIR-PAS) for Rapid Soil Quality Evaluation Abstract. The major function of soil is to provide fundamental natural resources for survival of plants, animals, and the human race. Soil functions depend on the balances of its structure and composition, well as the chemical, biological, and physical properties. It is become one important key aspect and routine activity in crop management system. To monitor and determine soil quality properties, several methods were already widely used in which most of them are based on solvent extraction followed by other laboratory procedures. However, these methods often require laborious and complicated processing for samples. They are time consuming and destructive. In last few decades, the application of infrared spectroscopy as non-destructive technique in determining soil quality properties (C, N, P and K) rapidly and simultaneously. Fourier transform infrared spectrum (FTIR) were acquired in wavelength range from 1000 to 2500 nm with applying photo-acoustic spectroscopy (PAS). Least square-support vector machine regression (LS-SVM) approach was then applied to predict soil quality properties. The results showed that C and N can be predicted accurately using FTIR-PAS whilst other parameters (P, K, Mg, Ca, S) can be predicted with maximum RPD index is 1.9. Moreover, soil clay, moisture and soil microbes were feasible to be detected by using FTIR-PAS combining with discriminant analysis (LS-DA) or cluster analysis (CA). It may conclude that FTIR-PAS technology can be used as a real time method in monitoring soil quality and fertility properties.

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Koch, Cosima, Andreas E. Posch, Christoph Herwig, and Bernhard Lendl. "Comparison of Fiber Optic and Conduit Attenuated Total Reflection (ATR) Fourier Transform Infrared (FT-IR) Setup for In-Line Fermentation Monitoring." Applied Spectroscopy 70, no. 12 (November 19, 2016): 1965–73. http://dx.doi.org/10.1177/0003702816662618.

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The performance of a fiber optic and an optical conduit in-line attenuated total reflection mid-infrared (IR) probe during in situ monitoring of Penicillium chrysogenum fermentation were compared. The fiber optic probe was connected to a sealed, portable, Fourier transform infrared (FT-IR) process spectrometer via a plug-and-play interface. The optical conduit, on the other hand, was connected to a FT-IR process spectrometer via a knuckled probe with mirrors that had to be adjusted prior to each fermentation, which were purged with dry air. Penicillin V (PenV) and its precursor phenoxyacetic acid (POX) concentrations were determined by online high-performance liquid chromatography and the obtained concentrations were used as reference to build partial least squares regression models. Cross-validated root-mean-square errors of prediction were found to be 0.2 g L−1 (POX) and 0.19 g L−1 (PenV) for the fiber optic setup and 0.17 g L−1 (both POX and PenV) for the conduit setup. Higher noise-levels and spectrum-to-spectrum variations of the fiber optic setup lead to higher noise of estimated (i.e., unknown) POX and PenV concentrations than was found for the conduit setup. It seems that trade-off has to be made between ease of handling (fiber optic setup) and measurement accuracy (optical conduit setup) when choosing one of these systems for bioprocess monitoring.

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Faguy, Peter W., William N. Richmond, Richard S. Jackson, Stephen C. Weibel, Gail Ball, and Joe H. Payer. "Real-Time Polarization Modulation in Situ Infrared Spectroscopy Applied to the Study of Atmospheric Corrosion." Applied Spectroscopy 52, no. 4 (April 1998): 557–64. http://dx.doi.org/10.1366/0003702981943879.

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A new methodology for the real-time in situ monitoring of atmospheric corrosion processes is presented. The mid-infrared spectra of surface films formed on polished copper substrates exposed to humid air containing sub-ppm levels of sulfur dioxide, nitric oxide, and hydrogen chloride were obtained by using a novel surface-sensitive infrared technique: real-time polarization modulation grazing angle reflection-absorption spectroscopy. The new methodology demonstrated improved signal-to-noise ratios, by a factor of 2.5, as compared to conventional Fourier transform infrared reflection absorption spectroscopy. Molecular spectroscopic data for water- and hydroxyl-containing species present at the metal surface were obtained with no interference from water vapor. Over the spectral region 4000–800 cm−1, bands were identified and assigned to nitro and nitrito adsorbates, to sulfite ions, and to bound water on the copper surface. Analysis of the time evolution and the profile composition of these bands is possible because of the sensitivity of this new optical sampling technique.

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Rando, Roy J., Rachele A. GibsonPresent address: Louisiana St, Cheol-Woong Kwon, Halet G. PooveyPresent address: Nelson Archi, and Henry W. Glindmeyer. "On-filter determination of collected wood dust by diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS)." Journal of Environmental Monitoring 7, no. 7 (2005): 675. http://dx.doi.org/10.1039/b502025e.

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Schenk, Jonas, Ian W. Marison, and Urs von Stockar. "Simplified Fourier-transform mid-infrared spectroscopy calibration based on a spectra library for the on-line monitoring of bioprocesses." Analytica Chimica Acta 591, no. 1 (May 2007): 132–40. http://dx.doi.org/10.1016/j.aca.2007.03.056.

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Juncan, Anca Maria, Florinela Fetea, and Carmen Socaciu. "APPLICATION OF FOURIER TRANSFORM INFRARED SPECTROSCOPY FOR THE CHARACTERIZATION OF SUSTAINABLE COSMETICS AND INGREDIENTS WITH ANTIOXIDANT POTENTIAL." Environmental Engineering and Management Journal 13, no. 1 (2014): 105–13. http://dx.doi.org/10.30638/eemj.2014.013.

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Larsen, Elisabeth S., William W. Hong, and Martin L. Spartz. "Hydrogen Sulfide Detection by UV-Assisted Infrared Spectrometry." Applied Spectroscopy 51, no. 11 (November 1997): 1656–67. http://dx.doi.org/10.1366/0003702971939325.

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Ultraviolet (UV)-assisted infrared (IR) spectroscopy has been evaluated for its potential usage and feasibility to indirectly detect hydrogen sulfide gas. Hydrogen sulfide (H2S) is a weakly IR-absorbing compound, and its detection by IR methods is further complicated by severe water interferences. However, H2S can readily be converted to sulfur dioxide (SO2), a strong IR absorber, via ultraviolet irradiation. A multipass IR White cell equipped with an internal mercury germicidal UV lamp has been interfaced to a Bomem MB series Fourier transform infrared (FT-IR) spectrometer. The conversion of hydrogen sulfide to sulfur dioxide (SO2) was tested in five matrices: nitrogen, ambient air, moisturized ambient air, dried ambient air, and zero-grade air. The conversion efficiency of H2S to SO2 in nitrogen, containing a negligible amount of oxygen, was approximately 25% and peaked at approximately 6 min of UV irradiation. In ambient air, the conversion efficiency was calculated to be ∼45% and peaked at 35 s of irradiation, while in the dried ambient air the SO2 concentration peaked in 85 s. In ambient air, the generated SO2 was destroyed during its production and was below detection within 90 s of irradiation. In the dried ambient air, the generated SO2 was still detectable at 120 s of irradiation. Moisturized ambient air was investigated to determine the degree of SO2 loss due to reaction with H2O. From these data, it appears that the water molecule and SO2 photolysis contribute only slightly to the SO2 loss. The greatest loss is apparently caused by reactive radicals such as ·OH generated during UV irradiation. Index Headings: FT-IR; UV photolysis; Vapor phase; H2S; SO2; Environmental analysis.

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Martinez, Iciar, Isabel Sánchez-Alonso, Carmen Piñeiro, Mercedes Careche, and Mónica Carrera. "Protein Signatures to Trace Seafood Contamination and Processing." Foods 9, no. 12 (November 26, 2020): 1751. http://dx.doi.org/10.3390/foods9121751.

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This review presents some applications of proteomics and selected spectroscopic methods to validate certain aspects of seafood traceability. After a general introduction to traceability and the initial applications of proteomics to authenticate traceability information, it addresses the application of proteomics to trace seafood exposure to some increasingly abundant emergent health hazards with the potential to indicate the geographic/environmental origin, such as microplastics, triclosan and human medicinal and recreational drugs. Thereafter, it shows the application of vibrational spectroscopy (Fourier-Transform Infrared Spectroscopy (FTIR) and Fourier-Transform Raman Spectroscopy (FT Raman)) and Low Field Nuclear Magnetic Resonance (LF-NMR) relaxometry to discriminate frozen fish from thawed fish and to estimate the time and temperature history of frozen fillets by monitoring protein modifications induced by processing and storage. The review concludes indicating near future trends in the application of these techniques to ensure seafood safety and traceability.

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LeBouf, Ryan F., Arthur L. Miller, Christopher Stipe, Jonathan Brown, Nate Murphy, and Aleksandr B. Stefaniak. "Comparison of field portable measurements of ultrafine TiO2: X-ray fluorescence, laser-induced breakdown spectroscopy, and Fourier-transform infrared spectroscopy." Environmental Science: Processes & Impacts 15, no. 6 (2013): 1191. http://dx.doi.org/10.1039/c3em00108c.

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STRANG, CHRISTOPHER R., and STEVEN P. LEVINE. "The Limits of Detection for the Monitoring of Semiconductor Manufacturing Gas and Vapor Emissions by Fourier Transform Infrared (FTIR) Spectroscopy." American Industrial Hygiene Association Journal 50, no. 2 (February 1989): 78–84. http://dx.doi.org/10.1080/15298668991374336.

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Viatte, C., B. Gaubert, M. Eremenko, F. Hase, M. Schneider, T. Blumenstock, M. Ray, P. Chelin, J. M. Flaud, and J. Orphal. "Tropospheric and total ozone columns over Paris (France) measured using medium-resolution ground-based solar-absorption Fourier-transform infrared spectroscopy." Atmospheric Measurement Techniques 4, no. 10 (October 25, 2011): 2323–31. http://dx.doi.org/10.5194/amt-4-2323-2011.

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Abstract. Ground-based Fourier-transform infrared (FTIR) solar absorption spectroscopy is a powerful remote sensing technique providing information on the vertical distribution of various atmospheric constituents. This work presents the first evaluation of a mid-resolution ground-based FTIR to measure tropospheric ozone, independently of stratospheric ozone. This is demonstrated using a new atmospheric observatory (named OASIS for "Observations of the Atmosphere by Solar absorption Infrared Spectroscopy"), installed in Créteil (France). The capacity of the technique to separate stratospheric and tropospheric ozone is demonstrated. Daily mean tropospheric ozone columns derived from the Infrared Atmospheric Sounding Interferometer (IASI) and from OASIS measurements are compared for summer 2009 and a good agreement of −5.6 (±16.1) % is observed. Also, a qualitative comparison between in-situ surface ozone measurements and OASIS data reveals OASIS's capacity to monitor seasonal tropospheric ozone variations, as well as ozone pollution episodes in summer 2009 around Paris. Two extreme pollution events are identified (on the 1 July and 6 August 2009) for which ozone partial columns from OASIS and predictions from a regional air-quality model (CHIMERE) are compared following strict criteria of temporal and spatial coincidence. An average bias of 0.2%, a mean square error deviation of 7.6%, and a correlation coefficient of 0.91 is found between CHIMERE and OASIS, demonstrating the potential of a mid-resolution FTIR instrument in ground-based solar absorption geometry for tropospheric ozone monitoring.

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LI-SHI, YING, and STEVEN P. LEVINE. "Evaluation of the Applicability of Fourier Transform Infrared (FTIR) Spectroscopy for Quantitation of the Components of Airborne Solvent Vapors in Air." American Industrial Hygiene Association Journal 50, no. 7 (July 1989): 360–65. http://dx.doi.org/10.1080/15298668991374804.

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Viatte, C., B. Gaubert, M. Eremenko, F. Hase, M. Schneider, T. Blumenstock, M. Ray, P. Chelin, J. M. Flaud, and J. Orphal. "Tropospheric and total ozone columns over Paris (France) measured using medium-resolution ground-based solar-absorption Fourier-transform infrared spectroscopy." Atmospheric Measurement Techniques Discussions 4, no. 3 (May 31, 2011): 3337–58. http://dx.doi.org/10.5194/amtd-4-3337-2011.

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Abstract. Ground-based Fourier-transform infrared (FTIR) solar absorption spectroscopy is a powerful remote sensing technique providing information on the vertical distribution of various atmospheric constituents. This work presents the first evaluation of a mid-resolution ground-based FTIR to measure tropospheric ozone, independently of stratospheric ozone. This is demonstrated using a new atmospheric observatory (named OASIS for "Observations of the Atmosphere by Solar absorption Infrared Spectroscopy"), installed in Créteil (France). Indeed, the information content of OASIS ozone retrievals is clearly sufficient to monitor separately tropospheric (from the surface up to 8 km) and stratospheric ozone. Daily mean tropospheric ozone columns derived from the Infrared Atmospheric Sounding Interferometer (IASI) and from OASIS measurements have been compared for summer 2009 and a good agreement of −5.6 (±16.1) % is observed. Also, a qualitative comparison between in-situ surface ozone measurements and OASIS data clearly shows OASIS's capacity to monitor seasonal tropospheric ozone variations, as well as ozone pollution episodes in summer 2009 around Paris. Two extreme pollution events were identified (on the 1 July and 6 August 2009) for which ozone partial columns from OASIS and predictions from a regional air-quality model (CHIMERE) were compared by respecting temporal and spatial coincidence criteria. Quantitatively, an average bias of 0.2 %, a mean square error deviation of 7.6 %, and a correlation coefficient of 0.91 was found between CHIMERE and OASIS. This demonstrates that a mid-resolution FTIR instrument in ground-based solar absorption geometry is a promising technique for monitoring tropospheric ozone.

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Patrizi, Barbara, Mario Siciliani de Cumis, Silvia Viciani, and Francesco D’Amato. "Dioxin and Related Compound Detection: Perspectives for Optical Monitoring." International Journal of Molecular Sciences 20, no. 11 (May 30, 2019): 2671. http://dx.doi.org/10.3390/ijms20112671.

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Dioxins and related compounds are environmental xenobiotics that are dangerous to human life, due to the accumulation and persistence in the environment and in the food chain. Cancer, reproductive and developmental issues, and damage to the immune system and endocrine system are only a few examples of the impact of such substances in everyday life. For these reasons, it is fundamental to detect and monitor these molecules in biological samples. The consolidated technique for analytical evaluation is gas chromatography combined with high-resolution mass spectrometry. Nowadays, the development of mid-infrared optical components like broadband laser sources, optical frequency combs, high performance Fourier-transform infrared spectroscopy, and plasmonic sensors open the way to new techniques for detection and real time monitoring of these organic pollutants in gaseous or liquid phase, with sufficient sensitivity and selectivity, and in short time periods. In this review, we report the latest techniques for the detection of dioxins, furans and related compounds based on optical and spectroscopic methods, looking at future perspectives.

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Kuha, P., K. Teanchai, S. Kongsriprapan, and Wichian Siriprom. "The Crystalline Monitoring of Oxide Compound: The Case Study of Influence from Heat Treatment." Advanced Materials Research 770 (September 2013): 311–14. http://dx.doi.org/10.4028/www.scientific.net/amr.770.311.

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In present study, the structural and thermal characterizations of the natural material were investigated, the relationship between the crystal structure and thermal treatment were studied. The relationship between temperature and features of the crystal structure were determined qualitative by three conventional analysis techniques, X-Ray Diffraction (XRD), Energy Dispersive X-Ray Fluorescence (EDXRF) and Fourier Transform Infrared Spectroscopy (FT-IR). The results show that theBabylonia areolatahave a crystalline of calcium carbonate in phase aragonite, and the rice husks have amorphous structure. Another that, both sample annealed under air atmosphere, the effect of temperature induced both materials have phase transformation. Both sample transformed into oxide compound at temperature about 900C. In addition, the composition of both mineral and the level of the metals element were investigated by EDXRF. Functional group and chemical environment of silicon ions and calcium ions were identified by FT-IR, respectively.

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Murphy, D. V., M. Osman, C. A. Russell, S. Darmawanto, and F. C. Hoyle. "Potentially mineralisable nitrogen: relationship to crop production and spatial mapping using infrared reflectance spectroscopy." Soil Research 47, no. 7 (2009): 737. http://dx.doi.org/10.1071/sr08096.

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Accurate and rapid prediction of the spatial structure of soil nitrogen (N) supply would have both economic and environmental benefits with respect to improved inorganic N fertiliser management. Yet traditional biochemical indices of soil N supply have not been widely incorporated into fertiliser decision support systems or environmental risk monitoring programs. Here we illustrate that in a low-input, semi-arid environment, potentially mineralisable N (PMN, as determined by anaerobic incubation) explained 21% of wheat grain yield (P = 0.003), whereas there was no significant relationship between wheat grain yield and inorganic N fertiliser application. We also assessed the spatial pattern of PMN using a structured grid soil sampling strategy over a 10-ha area (180 separate samples, 0–0.1 m). PMN in each soil sample was determined by standard biochemical analysis and also predicted using a fourier transform infrared spectrometer (FTIR). Findings illustrate that FTIR was able to significantly predict (P < 0.001) PMN values in soil and has the advantage of enabling high sample throughput and rapid (within minutes) soil analysis. Given the relatively low cost of FTIR machines and ease of use, such an approach has practical application in situations where analysis cost or access to equipped laboratories has hindered the measurement and monitoring of soil N supply within paddocks and across regions.

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Steiner, H., K. Staubmann, R. Allabashi, N. Fleischmann, A. Katzir, Y. Reichlin, and B. Mizaikoff. "Online sensing of volatile organic compounds in groundwater using mid-infrared fibre optic evanescent wave spectroscopy: a pilot scale test." Water Science and Technology 47, no. 2 (January 1, 2003): 121–26. http://dx.doi.org/10.2166/wst.2003.0100.

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A prototype sensing system for in-situ monitoring of volatile organic compounds in contaminated groundwater was tested at a pilot scale plant. The sensor consists of a commercially available Fourier transform infrared spectrometer, connected to a 6 m long infrared transparent silver halide fibre optic cable. A 10 cm long core-only section at the centre of the fibre is mounted on a sensor head and coated with a hydrophobic polymer layer, while the remaining fibre is protected by Teflon tubing and thus not in contact with the surrounding media. The sensor head was immersed into the monitoring wells of the pilot plant testing the sensor system under circumstances close to field conditions and typical for in-situ measurements. The pilot plant consists of a 1 m3 cubic tank filled with gravel. A pump is used to circulate water horizontally through the tank, simulating a natural aquifer. The evolution of the concentration of analytes injected into the system is monitored with time using the developed prototype sensing system. The results are validated by corresponding sampling and analysis with headspace gas chromatography.

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Phillips, Rebecca, David W. T. Griffith, Feike Dijkstra, Glenys Lugg, Roy Lawrie, and Ben Macdonald. "Tracking Short-Term Effects of Nitrogen-15 Addition on Nitrous Oxide Fluxes Using Fourier-Transform Infrared Spectroscopy." Journal of Environmental Quality 42, no. 5 (September 2013): 1327–40. http://dx.doi.org/10.2134/jeq2013.02.0067.

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Yang, Jiawei, Liulian Huang, Yonghao Ni, Lihui Chen, and Qingxian Miao. "Nano-SiO2 used with cationic polymer to improve the strength of sack paper." BioResources 16, no. 2 (March 19, 2021): 3348–59. http://dx.doi.org/10.15376/biores.16.2.3348-3359.

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As a green and sustainable packaging material, industrial sack paper has gained increased attention in recent years due to the public’s heightened environmental awareness. Practical applications for industrial packaging sack paper demands that the paper possess high physical strength properties. In this study, silicon dioxide (SiO2) nanoparticles in conjunction with poly(diallyldimethylammonium chloride) (PDADMAC) were applied to improve the physical strength of sack paper. The results showed that the physical strength properties of the sack paper increased with the addition of the SiO2 nanoparticles and PDADMAC, while the air permeability of the paper also remained high. Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) were used to characterize the sack paper with the SiO2 nanoparticle filler.

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Milazzotto, M. P., R. A. Bitar, J. A. Visintin, M. E. O. A. Assumpção, and H. S. Martinho. "316 FOURIER TRANSFORM INFRARED MICROSPECTROSCOPY: A NEW APPROACH FOR MOLECULAR PROFILE ANALYSIS OF SPERMATOZOA AND SEMINAL PLASMA." Reproduction, Fertility and Development 22, no. 1 (2010): 314. http://dx.doi.org/10.1071/rdv22n1ab316.

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Fourier transform infrared (FT-IR) spectroscopy is a potential tool for noninvasive optical tissue diagnosis. Applications of this technique for non-clinical purposes have increased since it has been shown that it can also provide the identification of functional groups, bonding types, and molecular conformations. Moreover, the spectral bands are molecule-specific and provide direct information about the biochemical composition. However, the exploitation of FT-IR spectroscopy for reproductive studies is still limited. The aim of this study was to determine molecular profiles of spermatozoa and seminal plasma from different species to define important peaks present in the natural tissues. The study was based on fresh semen samples from 4 different species (human, bovine, ovine, and porcine). Semen samples were collected and evaluated for concentration and motility parameters. After that, samples were centrifuged and the seminal plasma was transferred to another tube. Spermatozoa were washed three times in PBS and 5 × 106 cells were resuspended in 50 μL of deionized water. Samples of 2 μL from spermatozoa and seminal plasma were placed separately on a gold slide and left to dry for 15 min in air. Spectral data were collected on a FT-IR spectrometer (Model 610; Varian Inc., Palo Alto, CA, USA). The absorbance spectra were acquired in reflectance mode at a spectral resolution of 2 cm-1 with 400 scans co-added. Apodization was performed using a triangular function. The system enabled spectra to be acquired from a sample area of approximately 200 μm2 in about 2 min. The preliminary tentative vibrational bands assignment was performed based on literature. Spectral differences among species were statistically validated with principal components analysis and clustering. The main spectral differences among spermatozoa spectral bands were observed in the DNA/RNA (A, B, and Z conformations), glycogen, lipids, fatty acids, cholesterol, and phospholipids vibrational bands. For seminal plasma, main spectral differences were found at the 1500-1700 cm-1 spectral region assigned to protein secondary structure (amide I and amide II). Increasing a-helix, fi-sheet, fi-turn bands assignments suggests the presence of fragmented protein in human, ovine, and porcine seminal plasma spectra. These results suggest compositional similarity among these 3 species compared to the bovine. In conclusion, FT-IR spectroscopy could provide relevant information related to spermatozoa and seminal plasma physiology useful in improving freezing methods and fertility monitoring. More studies will be needed to establish the relationship between spectral features and physiological processes.

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Yang, Lingfang, Zhou Shi, and Wenhao Yang. "Characterization of air plasma-activated carbon nanotube electrodes for the removal of lead ion." Water Science and Technology 69, no. 11 (March 24, 2014): 2272–78. http://dx.doi.org/10.2166/wst.2014.157.

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Carbon nanotube electrodes were prepared by pressing a mixture of carbon nanotubes and polytetrafluoroethylene (which acted as a binder) on a stainless steel net collector, and the electrodes were subsequently activated in our self-designed plasma apparatus, using air plasma. The morphology and surface functional groups of the electrodes were characterized using scanning electron microscopy and Fourier transform infrared spectroscopy, respectively. The results showed that the electrodes activated by air plasma possessed a rougher surface and more oxygen-containing groups than the raw electrodes, properties that were beneficial for their electrosorption performance. After 5 min of air plasma activation, the lead ion electrosorption capacity of the activated electrodes (measured at 450 mV) increased to 3.40 mg/g, which was 73% higher than the capacity of the non-activated, raw electrode, and 5.76 times the adsorption capacity of the raw electrode at 0 mV. The results of this study indicate that air plasma activation can be used to effectively enhance the electrosorption capacity of carbon nanotube electrodes.

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Fabian, Heinz, Lin-P'Ing Choo, Gyorgyi I. Szendrei, Michael Jackson, William C. Halliday, Laszlo Otvos, and Henry H. Mantsch. "Infrared Spectroscopic Characterization of Alzheimer Plaques." Applied Spectroscopy 47, no. 9 (September 1993): 1513–18. http://dx.doi.org/10.1366/0003702934067469.

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Neuritic plaques in the brains of victims of Alzheimer's disease are primarily composed of a 42 amino acid polypeptide, the β-amyloid peptide (βA4), the neurotoxicity of which is related to its aggregation. Fourier transform infrared spectroscopy has been used to study the conformational properties of two synthetic analogues of βA4 peptides known to be involved in the formation of the neuritic plaques formed in patients with Alzheimer's disease and the influence of a single, naturally occurring point mutation upon the tendency of the peptide to aggregate. Peptides from both “normal” Alzheimer's and the more severe Dutch variant of the disease were found to form aggregated antiparallel strands. However, the replacement of a single, negatively charged amino acid (glutamic acid) with an uncharged amino acid (glutamine) in the Dutch-type peptide results in significant differences in the strength and stability of these aggregates and the microenvironment of a number of amino acids. The differences in the strength and the stability of the aggregates are attributed to the presence of varying (small) proportions of the classical secondary structures and differences in net charge. Environmental (solvent) effects were shown to significantly affect the strength of the inter-molecular hydrogen bonding in the aggregates, solvent systems mimicking the membrane/water interface resulting in more strongly hydrogen bonded aggregates. Infrared spectra of material from autopsied human Alzheimer's brains show spectral features indicative of the formation of similar aggregates, which may be related to plaque formation. This observation suggests that IR spectroscopic methods may in the future be useful in the diagnosis and monitoring of Alzheimer's disease.

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Tournadre, Benoît, Pascale Chelin, Mokhtar Ray, Juan Cuesta, Rebecca D. Kutzner, Xavier Landsheere, Audrey Fortems-Cheiney, et al. "Atmospheric ammonia (NH<sub>3</sub>) over the Paris megacity: 9 years of total column observations from ground-based infrared remote sensing." Atmospheric Measurement Techniques 13, no. 7 (July 21, 2020): 3923–37. http://dx.doi.org/10.5194/amt-13-3923-2020.

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Abstract. In this paper, we present the first multiyear time series of atmospheric ammonia (NH3) ground-based measurements in the Paris region (Créteil, 48.79∘ N, 2.44∘ E, France) retrieved with the midresolution “Observations of the Atmosphere by Solar absorption Infrared Spectroscopy” (OASIS) ground-based Fourier transform infrared solar observatory. Located in an urban region, OASIS has previously been used for monitoring air quality (tropospheric ozone and carbon monoxide) thanks to its specific column sensitivity across the whole troposphere down to the atmospheric boundary layer. A total of 4920 measurements of atmospheric total columns of ammonia have been obtained from 2009 to 2017, with uncertainties ranging from 20 % to 35 %, and have been compared with NH3 concentrations derived from the Infrared Atmospheric Sounding Interferometer (IASI). OASIS ground-based measurements show significant interannual and seasonal variabilities of atmospheric ammonia. NH3 total columns over the Paris megacity (12 million people) vary seasonally by 2 orders of magnitude from approximately 0.1×1016 molec. cm−2 in winter to 10×1016 molec. cm−2 for spring peaks, probably due to springtime spreading of fertilizers on surrounding croplands.

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Grosjean, Daniel, Ernesto C. Tuazon, and Eric Fujita. "Ambient formic acid in southern California air: a comparison of two methods, Fourier transform infrared spectroscopy and alkaline trap-liquid chromatography with UV detection." Environmental Science & Technology 24, no. 1 (January 1990): 144–46. http://dx.doi.org/10.1021/es00071a019.

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Hong, Daewoong, and Seogyeon Cho. "Improved Methods for Performing Multivariate Analysis and Deriving Background Spectra in Atmospheric Open-Path FT-IR Monitoring." Applied Spectroscopy 57, no. 3 (March 2003): 299–308. http://dx.doi.org/10.1366/000370203321558218.

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Open-path Fourier transform infrared spectrometry (OP/FT-IR) may improve the temporal and spatial resolution in air pollutant measurements compared to conventional sampling methods. However, a successful OP/FT-IR operation requires an experienced analyst to resolve chemical interference as well as to derive a suitable background spectrum. The present study aims at developing a systematic method of handling the OP/FT-IR derived spectra for the measurement of photochemical oxidants and volatile organic compounds (VOCs) in urban areas. A classical least-squares (CLS) method, the most frequently used regression method in OP/FT-IR, is modified to constrain all the analyzed chemical species concentrations within a physically reasonable range. This new CLS method, named constrained CLS, may save the effort of predetermining the chemical species to be analyzed. A new background spectrum generation method is also introduced to more efficiently handle chemical interferences. Finally, CLS is shown to be prone to propagating errors in the case that a few data points contain a significant amount of error. The L1-norm minimization method reduces this error propagation to considerably increase the stability compared to CLS. The presently developed analysis software based on these approaches is compared with the other conventional CLS method using an artificially made single-beam spectrum as well as a field single-beam spectrum.

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Stankiewicz, B., B. Mossety-Leszczak, L. Byczynski, and M. Kisiel. "Synergistic effect on the degradation rate of pultruded glass fiber-reinforced polymer bridge panel after 20 years of exploitation." Journal of Composite Materials 52, no. 18 (December 28, 2017): 2527–35. http://dx.doi.org/10.1177/0021998317749713.

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Glass fiber-reinforced polymer pultruded profiles have great potential in the construction industry, presenting certain advantages when compared with traditional materials, including the potentially improved durability under fluctuating levels of environmental factors. The paper presents analysis of glass fiber-reinforced polymer composite, acquired from cable-stayed Fiberline Bridge exploited for 20 years in the fjord area of Kolding, Denmark. Fragment of composite material used for Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis tests was therefore subjected to natural aging as a result of temperature amplitudes, permanent solar radiation as well as aggressive impact of sea salt contained in the moisture in the air around the coastal area. Complex comparative analysis presented in this paper, and based on Fourier transform infrared, thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis tests, pertained to both unspool composite glass fiber-reinforced polymer material (composite 1) and the one after 20 years of natural aging (composite 2). Dynamic mechanical analysis was allowed to detect thermal effects based on the changes in the modulus or damping behavior. The differential scanning calorimetry experiments were performed on the glass fiber-reinforced polymer material in order to determine the mass variation and the energy changes suffered by the materials, as a function of temperature and time.

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Liu, Fu-Juan, Xi-Jia Zhang, and Xin Li. "Silkworm (Bombyx mori) cocoon vs. wild cocoon multi-layer structure and performance characterization." Thermal Science 23, no. 4 (2019): 2135–42. http://dx.doi.org/10.2298/tsci1904135l.

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As protective shells for their biological functions against environmental damage and attack by natural predators, the silkworm (Bombyx mori) cocoon and its wild partner have distinctive multi-layer structures, which are systematically studied in this paper by the SEM, the thermogravimetric analyzer, and the Fourier transform infrared spectroscopy. Their mechanical properties are also investigated for the whole hierarchy and each cascade as well. In order to better demonstrate the superior survivability of cocoons in harsh environments, air permeability and moisture vapor transmission rate of the silkworm cocoon are tested. The results show the silkworm cocoons have excellent air permeability and moisture vapor transmission rate. A better understanding of different cocoons? bio-functions will be of particular importance to design thermal textiles and provide better comfort and safety for clothing in future.

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Phillips, Frances A., Travis Naylor, Hugh Forehead, David W. T. Griffith, John Kirkwood, and Clare Paton-Walsh. "Vehicle Ammonia Emissions Measured in An Urban Environment in Sydney, Australia, Using Open Path Fourier Transform Infra-Red Spectroscopy." Atmosphere 10, no. 4 (April 19, 2019): 208. http://dx.doi.org/10.3390/atmos10040208.

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Airborne particulate matter (PM) is a major health risk in urban settings. Ammonia (NH3) from vehicle exhaust is an under-recognised ingredient in the formation of inorganic PM and there remains a shortage of data to properly quantify the role of NH3 from vehicles in PM formation. An Open-path Fourier transform infra-red (OP-FTIR) spectrometer measured atmospheric NH3, carbon monoxide (CO) and carbon dioxide (CO2) at high temporal resolution (5 min) in Western Sydney over 11 months. The oxides of nitrogen (NO2 and NO; NOx) and sulphur dioxide (SO2) were measured at an adjacent air quality monitoring station. NH3 levels were maxima in the morning and evening coincident with peak traffic. During peak traffic NH3:CO ratio ranged from 0.018 to 0.022 ppbv:ppbv. Results were compared with the Greater Metropolitan Region 2008 (GMR2008) emissions inventory. Measured NH3:CO was higher during peak traffic times than the GMR2008 emissions estimates, indicating an underestimation of vehicle NH3 emissions in the inventory. Measurements also indicated the urban atmosphere was NH3 rich for the formation of ammonium sulphate ((NH4)2SO4) particulate was SO2 limited while the formation of ammonium nitrate (NH4NO3) was NH3 limited. Any reduction in NOx emissions with improved catalytic converter efficiency will be accompanied by an increase in NH3 production and potentially with an increase in NH4NO3 particulate.

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Zellweger, Christoph, Rainer Steinbrecher, Olivier Laurent, Haeyoung Lee, Sumin Kim, Lukas Emmenegger, Martin Steinbacher, and Brigitte Buchmann. "Recent advances in measurement techniques for atmospheric carbon monoxide and nitrous oxide observations." Atmospheric Measurement Techniques 12, no. 11 (November 8, 2019): 5863–78. http://dx.doi.org/10.5194/amt-12-5863-2019.

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Abstract. Carbon monoxide (CO) and nitrous oxide (N2O) are two key parameters in the observation of the atmosphere, relevant to air quality and climate change, respectively. For CO, various analytical techniques have been in use over the last few decades. In contrast, N2O was mainly measured using gas chromatography (GC) with an electron capture detector (ECD). In recent years, new spectroscopic methods have become available which are suitable for both CO and N2O. These include infrared (IR) spectroscopic techniques such as cavity ring-down spectroscopy (CRDS), off-axis integrated cavity output spectroscopy (OA-ICOS) and Fourier transform infrared spectroscopy (FTIR). Corresponding instruments became recently commercially available and are increasingly used at atmospheric monitoring stations. We analysed results obtained through performance audits conducted within the framework of the Global Atmosphere Watch (GAW) quality management system of the World Meteorology Organization (WMO). These results reveal that current spectroscopic measurement techniques have clear advantages with respect to data quality objectives compared to more traditional methods for measuring CO and N2O. Further, they allow for a smooth continuation of historic CO and N2O time series. However, special care is required concerning potential water vapour interference on the CO amount fraction reported by near-IR CRDS instruments. This is reflected in the results of parallel measurement campaigns, which clearly indicate that drying the sample air leads to an improved accuracy of CO measurements with such near-IR CRDS instruments.

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Borrás, Esther, Luis A. Tortajada-Genaro, Milagro Ródenas, Teresa Vera, Thomas Speak, Paul Seakins, Marvin D. Shaw, Alastair C. Lewis, and Amalia Muñoz. "On-line solid phase microextraction derivatization for the sensitive determination of multi-oxygenated volatile compounds in air." Atmospheric Measurement Techniques 14, no. 7 (July 19, 2021): 4989–99. http://dx.doi.org/10.5194/amt-14-4989-2021.

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Abstract. Multi-oxygenated volatile organic compounds are important markers of air pollution and precursors of ozone and secondary aerosols in both polluted and remote environments. Herein, their accurate determination was enhanced. The approach was based on an automated system for active sampling and on-fibre derivatization coupled with the gas chromatography–mass spectrometry (GC–MS) technique. The method capability was determined for different compound families, such as aldehydes, ketones, α-dicarbonyls, hydroxy-aldehydes, hydroxy-ketones, and carboxylic acids. A good accuracy (<7 %) was demonstrated from the results compared to Fourier-transform infrared spectroscopy (FTIR). Limits of detection (LODs) of 6–100 pptV were achieved with a time resolution lower than 20 min. The developed method was successfully applied to the determination of multi-oxygenated compounds in air samples collected during an intercomparison campaign (EUROCHAMP-2020 project). Also, its capability and accuracy for atmospheric monitoring was demonstrated in an isoprene ozonolysis experiment. Both were carried out in the high-volume outdoor atmospheric simulation chambers (EUPHORE, 200 m3). In summary, our developed technique offers near-real-time monitoring with direct sampling, which is an advantage in terms of handling and labour time for a proper quantification of trace levels of atmospheric multi-oxygenated compounds.

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Journal articles on the topic 'Environmental monitoring Air Fourier transform infrared spectroscopy'

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