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Fang B, Yang N, Zhao W, Wang C, Zhang W, Song W, Venables DS, Chen W. Improved spherical mirror multipass-cell-based interband cascade laser spectrometer for detecting ambient formaldehyde at parts per trillion by volume levels. APPLIED OPTICS 2019; 58:8743-8750. [PMID: 31873651 DOI: 10.1364/ao.58.008743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 10/10/2019] [Indexed: 06/10/2023]
Abstract
We report the development of an improved spherical mirror multipass-cell-based interband cascade laser (ICL) spectrometer for ambient formaldehyde (HCHO) detection. The multipass cell consists of two easily manufactured spherical mirrors that are low cost, and have a simple structure, large mirror area utilization, and dense spot pattern. Optical interference caused by the multipath cell was largely reduced, resulting in good sensitivity. Using wavelength modulation spectroscopy (WMS), a detection precision (${1} \sigma $1σ) of 51 pptv in 10 s was achieved with an absorption pathlength of 96 m, which compared favorably with the performance of other state-of-the-art instruments. The precision can be further improved by using a long absorption pathlength configuration and by removing fringe-like optical noise caused by the collimation lens. Ambient application of the developed spectrometer was demonstrated.
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Lewis T, Heard DE, Blitz MA. A novel multiplex absorption spectrometer for time-resolved studies. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:024101. [PMID: 29495797 DOI: 10.1063/1.5006539] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A Time-Resolved Ultraviolet/Visible (UV/Vis) Absorption Spectrometer (TRUVAS) has been developed that can simultaneously monitor absorption at all wavelengths between 200 and 800 nm with millisecond time resolution. A pulsed photolysis laser (KrF 248 nm) is used to initiate chemical reactions that create the target species. The absorption signals from these species evolve as the composition of the gas in the photolysis region changes over time. The instrument can operate at pressures over the range ∼10-800 Torr and can measure time-resolved absorbances <10-4 in the UV (300 nm) and even lower in the visible (580 nm) 2.3 × 10-5, with the peak of sensitivity at ∼500 nm. The novelty of this setup lies in the arrangement of the multipass optics. Although appearing similar to other multipass optical systems (in particular the Herriott cell), there are fundamental differences, most notably the ability to adjust each mirror to maximise the overlap between the probe beam and the photolysis laser. Another feature which aids the sensitivity and versatility of the system is the use of 2 high-throughput spectrographs coupled with sensitive line-array CCDs, which can measure absorbance from ∼200 to 800 nm simultaneously. The capability of the instrument is demonstrated via measurements of the absorption spectrum of the peroxy radical, HOCH2CH2O2, and its self-reaction kinetics.
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Affiliation(s)
- Thomas Lewis
- School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Dwayne E Heard
- School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Mark A Blitz
- School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
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Schwemmer G, Yakshin M, Prasad C, Hanisco T, Mylapore AR, Hwang I, Lee S. Injection Seeded Laser for Formaldehyde Differential Fluorescence Lidar. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201611902004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Dong L, Yu Y, Li C, So S, Tittel FK. Ppb-level formaldehyde detection using a CW room-temperature interband cascade laser and a miniature dense pattern multipass gas cell. OPTICS EXPRESS 2015; 23:19821-19830. [PMID: 26367641 DOI: 10.1364/oe.23.019821] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A ppb-level formaldehyde (H2CO) sensor was developed using a thermoelectrically cooled (TEC), continuous-wave (CW) room temperature interband cascade laser (ICL) emitting at 3.59 μm and a miniature dense pattern multipass gas cell with >50 m optical path length. Performance of the sensor was investigated with two measurement schemes: direct absorption (DAS) and wavelength modulation spectroscopy (WMS). With an integration time of less than 1.5 second, a detection limit of ~3 ppbv for H2CO measurement with precision of 1.25 ppbv for DAS and 0.58 ppbv for WMS, respectively, was achieved without zero air based background subtraction. An Allan-Werle variance analysis indicated that the precisions can be further improved to 0.26 ppbv @ 300s for DAS and 69 pptv @ 90 s for WMS, respectively. A side-by-side comparison between two measurement schemes is also discussed in detail.
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Nozière B, Kalberer M, Claeys M, Allan J, D'Anna B, Decesari S, Finessi E, Glasius M, Grgić I, Hamilton JF, Hoffmann T, Iinuma Y, Jaoui M, Kahnt A, Kampf CJ, Kourtchev I, Maenhaut W, Marsden N, Saarikoski S, Schnelle-Kreis J, Surratt JD, Szidat S, Szmigielski R, Wisthaler A. The molecular identification of organic compounds in the atmosphere: state of the art and challenges. Chem Rev 2015; 115:3919-83. [PMID: 25647604 DOI: 10.1021/cr5003485] [Citation(s) in RCA: 211] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Barbara Nozière
- †Ircelyon/CNRS and Université Lyon 1, 69626 Villeurbanne Cedex, France
| | | | | | | | - Barbara D'Anna
- †Ircelyon/CNRS and Université Lyon 1, 69626 Villeurbanne Cedex, France
| | | | | | | | - Irena Grgić
- ○National Institute of Chemistry, 1000 Ljubljana, Slovenia
| | | | | | - Yoshiteru Iinuma
- ¶Leibniz-Institut für Troposphärenforschung, 04318 Leipzig, Germany
| | | | | | | | - Ivan Kourtchev
- ‡University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Willy Maenhaut
- §University of Antwerp, 2000 Antwerp, Belgium.,□Ghent University, 9000 Gent, Belgium
| | | | | | | | - Jason D Surratt
- ▼University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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Li X, Wang S, Zhou R, Zhou B. Urban atmospheric formaldehyde concentrations measured by a differential optical absorption spectroscopy method. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2014; 16:291-297. [PMID: 24362786 DOI: 10.1039/c3em00545c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this study a differential optical absorption spectroscopy (DOAS) method was used to monitor formaldehyde (HCHO) concentrations in Shanghai ambient air at a research station in Fudan University. The measurements were carried out during April 2010-April 2011 and a total of 120 940 recorded data points were obtained. The average HCHO concentration was found to be the highest (10.0 ppbv) during August 2010 and the lowest (2.0 ppbv) during April 2010. The diurnal variation of HCHO and O3 followed very similar trends in all the seasons. This was evident from the fact that HCHO had a strong positive correlation with O3. Both peaked once in the morning (07:00-09:00 local time), and once in the night (16:00-19:00 local time). The peak concentrations varied from season to season, which could be attributed to the seasonal variation in anthropogenic activity, traffic movement and atmospheric boundary layer conditions. The background HCHO concentration in 2011 winter (similar to 12.0 ppbv) was an order of magnitude higher than that observed in 2010 spring (similar to 2.0 ppbv); corresponding with the results of several pollution controls adopted by the Shanghai administrative government before and after the EXPO 2010 period (May 1, 2010-Oct. 31 2010). This study contributed the basic information for understanding the concentration level and the chemical processes of atmospheric HCHO in a major metropolitan area.
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Affiliation(s)
- Xiang Li
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, 220 Handan Road, Shanghai 200433, China.
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Sassine M, Picquet-Varrault B, Perraudin E, Chiappini L, Doussin JF, George C. A new device for formaldehyde and total aldehydes real-time monitoring. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:1258-1269. [PMID: 23892614 DOI: 10.1007/s11356-013-2010-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 07/12/2013] [Indexed: 06/02/2023]
Abstract
A new sensitive technique for the quantification of formaldehyde (HCHO) and total aldehydes has been developed in order to monitor these compounds, which are known to be involved in air quality issues and to have health impacts. Our approach is based on a colorimetric method where aldehydes are initially stripped from the air into a scrubbing solution by means of a turning coil sampler tube and then derivatised with 3-methylbenzothiazolinone-2-hydrazone in acid media (pH = -0.5). Hence, colourless aldehydes are transformed into blue dyes that are detected by UV-visible spectroscopy at 630 nm. Liquid core waveguide LCW Teflon® AF-2400 tube was used as innovative optical cells providing a HCHO detection limit of 4 pptv for 100 cm optical path with a time resolution of 15 min. This instrument showed good correlation with commonly used techniques for aldehydes analysis such as DNPH derivatisation chromatographic techniques with off-line and on-line samplers, and DOAS techniques (with deviation below 6%) for both indoor and outdoor conditions. This instrument is associated with simplicity and low cost, which is a prerequisite for indoor monitoring.
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Affiliation(s)
- Maria Sassine
- Université Lyon 1; CNRS, UMR5256, IRCELYON, Institut de Recherches sur la Catalyse et l'Environnement de Lyon, Villeurbanne, France
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Borbon A, Ruiz M, Bechara J, Aumont B, Chong M, Huntrieser H, Mari C, Reeves CE, Scialom G, Hamburger T, Stark H, Afif C, Jambert C, Mills G, Schlager H, Perros PE. Transport and chemistry of formaldehyde by mesoscale convective systems in West Africa during AMMA 2006. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jd017121] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Weibring P, Richter D, Walega JG, Rippe L, Fried A. Difference frequency generation spectrometer for simultaneous multispecies detection. OPTICS EXPRESS 2010; 18:27670-81. [PMID: 21197041 DOI: 10.1364/oe.18.027670] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
A difference-frequency generation based spectrometer system for simultaneous ultra-sensitive measurements of formaldehyde (CH2O) and Methane (CH4) is presented. A new multiplexing approach using collinear quasi-phase-matching in a single grating period of periodically poled lithium niobate (PPLN) is discussed and demonstrated for two pairs of pump and signal lasers to generate mid-infrared frequencies at 2831.64 cm(-1) and 2916.32 cm(-1), respectively. The corresponding absorption signals are discriminated by modulating the DFB diode lasers at modulation frequencies of 40 kHz and 50 kHz, respectively, and using a computer based modulation and de-modulation scheme. In addition, simultaneous measurements of CH2O, CH4 and H2O are demonstrated utilizing both collinear and non-collinear quasi-phase-matching.
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Affiliation(s)
- Petter Weibring
- National Center for Atmospheric Research, Earth Observing Laboratory, Boulder, Colorado 80301, USA.
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Johnson TJ, Sams RL, Burton SD, Blake TA. Absolute integrated intensities of vapor-phase hydrogen peroxide (H2O2) in the mid-infrared at atmospheric pressure. Anal Bioanal Chem 2009; 395:377-86. [DOI: 10.1007/s00216-009-2805-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2009] [Revised: 04/09/2009] [Accepted: 04/15/2009] [Indexed: 11/30/2022]
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Hottle JR, Huisman AJ, DiGangi JP, Kammrath A, Galloway MM, Coens KL, Keutsch FN. A laser induced fluorescence-based instrument for in-situ measurements of atmospheric formaldehyde. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:790-5. [PMID: 19245018 DOI: 10.1021/es801621f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Direct, in situ detection of gas phase formaldehyde (HCHO) via laser induced fluorescence in a White-type multipass cell is demonstrated with a (3sigma) limit of detection of approximately 0.051 parts per billion by volume in a 1 s sampling time. Calibration is performed in two ways: using permeation tubes and with air bubbled through an aqueous solution of HCHO. The concentration of HCHO output from the bubbler is measured by cavity ring-down spectroscopy. Measurement of ambient HCHO is carried out at the University of Wisconsin, Madison for a period of several days.
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Affiliation(s)
- John R Hottle
- University of Wisconsin-Madison, Department of Chemistry, 1101 University Ave, Madison, Wisconsin 53706, USA
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Fried A, Walega JG, Olson JR, Crawford JH, Chen G, Weibring P, Richter D, Roller C, Tittel FK, Heikes BG, Snow JA, Shen H, O'Sullivan DW, Porter M, Fuelberg H, Halland J, Millet DB. Formaldehyde over North America and the North Atlantic during the summer 2004 INTEX campaign: Methods, observed distributions, and measurement-model comparisons. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009185] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Snow JA, Heikes BG, Shen H, O'Sullivan DW, Fried A, Walega J. Hydrogen peroxide, methyl hydroperoxide, and formaldehyde over North America and the North Atlantic. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jd007746] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Roller CB, Holland BP, McMillen G, Step DL, Krehbiel CR, Namjou K, McCann PJ. Measurement of exhaled nitric oxide in beef cattle using tunable diode laser absorption spectroscopy. APPLIED OPTICS 2007; 46:1333-42. [PMID: 17318254 DOI: 10.1364/ao.46.001333] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Measurement of nitric oxide (NO) in the expired breath of crossbred calves received at a research facility was performed using tunable diode laser absorption spectroscopy. Exhaled NO (eNO) concentrations were measured using NO absorption lines at 1912.07 cm(-1) and employing background subtraction. The lower detection limit and measurement precision were determined to be approximately 330 parts in 10(12) per unit volume. A custom breath collection system was designed to collect lower airway breath of spontaneously breathing calves while in a restraint chute. Breath was collected and analyzed from calves upon arrival and periodically during a 42 day receiving period. There was a statistically significant relationship between eNO, severity of bovine respiratory disease (BRD) in terms of number of times treated, and average daily weight gain over the first 15 days postarrival. In addition, breathing patterns and exhaled CO2 showed a statistically significant relationship with BRD morbidity.
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Affiliation(s)
- C B Roller
- Department of Animal Science, Oklahoma State University, Oklahoma 74078, USA.
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Millet DB, Jacob DJ, Turquety S, Hudman RC, Wu S, Fried A, Walega J, Heikes BG, Blake DR, Singh HB, Anderson BE, Clarke AD. Formaldehyde distribution over North America: Implications for satellite retrievals of formaldehyde columns and isoprene emission. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006853] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Co DT, Hanisco TF, Anderson JG, Keutsch FN. Rotationally Resolved Absorption Cross Sections of Formaldehyde in the 28100−28500 cm-1 (351−356 nm) Spectral Region: Implications for in Situ LIF Measurements. J Phys Chem A 2005; 109:10675-82. [PMID: 16863116 DOI: 10.1021/jp053466i] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The rotationally resolved ultraviolet absorption cross sections for the 2(0)(0)4(1)(0) vibrational band of the A(1)A(2)-X(1)A(1) electronic transition of formaldehyde (HCHO) at an apodized resolution of 0.027 cm(-1) (approximately 0.0003 nm at 352 nm) over the spectral range 28100-28500 cm(-1) (351-356 nm) at 298 and 220 K, using Fourier transform spectroscopy, are first reported here. Accurate rotationally resolved cross sections are important for the development of in situ HCHO laser-induced fluorescence (LIF) instruments and for atmospheric monitoring. Pressure dependence of the cross sections between 75 and 400 Torr at 298 K was explored, and an average pressure broadening coefficient in dry air of 1.8 x 10(-4) cm(-1) Torr(-1) for several isolated lines is reported. Gaseous HCHO was quantitatively introduced into a flow cell by evaporating micron-sized droplets of HCHO solution, using a novel microinjector technique. The condensed-phase concentrations of HCHO were determined by iodometric titrations to an accuracy of <1%. Accuracy of the measured absorption cross sections is estimated to be better than +/-5%. Integrated and differential cross sections over the entire band at low resolution (approximately 1 cm(-1)) obtained with our calibration technique are in excellent agreement with previous measurements. A maximum differential cross section of 5.7 x 10(-19) cm(2) molecule(-1) was observed at high resolution-almost an order of magnitude greater than any previously reported data at low resolution.
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Affiliation(s)
- Dick T Co
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
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Dasgupta PK, Li J, Zhang G, Luke WT, McClenny WA, Stutz J, Fried A. Summertime ambient formaldehyde in five U.S. metropolitan areas: Nashville, Atlanta, Houston, Philadelphia, and Tampa. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2005; 39:4767-83. [PMID: 16053074 DOI: 10.1021/es048327d] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
First, we briefly review the atmospheric chemistry and previous intercomparison measurements for HCHO, with special reference to the diffusion scrubber Hantzsch reaction based fluorescence instrument used in the field studies reported herein. Then we discuss summertime HCHO levels in five major U.S. cities measured over 1999-2002, primarily from ground-based measurements. Land-sea breeze circulations play a major role in observed concentrations in coastal cities. Very high HCHO peak mixing ratios were observed in Houston (>47 ppb) where the overall median mixing ratio was 3.3 ppb; the corresponding values in Atlanta were approximately >18 and 7.9 ppb, respectively. The peak and median mixing ratios (9.3 and 2.3 ppb) were the lowest for Tampa, where the land-sea breeze also played an important role. In several cities, replicate HCHO measurements were made by direct spectroscopic instruments; the instruments were located kilometers from each other and addressed very different heights (e.g., 106 vs 10 m). Even under these conditions, there was remarkable qualitative and often quantitative agreement between the different instruments, when they were all sampling the same air mass within a short period of each other. Local chemistry dominates how HCHO is formed and dissipated. The high concentrations in Houston resulted from emissions near the ship channel; the same formaldehyde plume was measured at two sites and clearly ranged over tens of kilometers. Local micrometeorology is another factor. HCHO patterns measured at a high-rise site in downtown Nashville were very much in synchrony with other ground sites 12 km away until July 4 celebrations whence HCHO concentrations at the downtown site remained elevated for several days and nights. The formation and dissipation of HCHO in the different cities are discussed in terms of other concurrently measured species and meteorological vectors. The vertical profiles of HCHO in and around Tampa under several different atmospheric conditions are presented. The extensive data set represented in this paper underscores that urban HCHO measurements can now be made easily; the agreement between disparate instruments (that are independently calibrated or rely on the absolute absorption cross section) further indicates that such measurements can be done reliably and accurately for this very important atmospheric species. The data set presented here can be used as a benchmark for future measurements if the use of formaldehyde precursors such as methanol or methyl tert-butyl ether (MTBE) as oxygenated fuel additives increases in the future.
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Affiliation(s)
- Purnendu K Dasgupta
- Department of Chemistry, Texas Tech University, Lubbock, Texas 79409-1061, USA.
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Chen J, So S, Lee H, Fraser MP, Curl RF, Harman T, Tittel FK. Atmospheric formaldehyde monitoring in the Greater Houston area in 2002. APPLIED SPECTROSCOPY 2004; 58:243-7. [PMID: 17140485 DOI: 10.1366/000370204322843002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
A laser spectrometer based on difference frequency generation (DFG) was deployed for real-time long-term monitoring of HCHO concentrations at an environmental monitoring site located at Deer Park, Texas, in the Greater Houston area. Three HCHO concentration measurements were made during the periods of July 20-31 (period I), August 2-14 (period II), and August 24-September 25 (period III), 2002. In periods I and II, differences in HCHO concentrations are apparent between day and night measurements, with elevated concentrations during daylight hours. Most of the HCHO peak values are less than 20 ppbV except for two intense peaks on August 02 (approximately 25 ppbV) and August 04 (approximately 30 ppbV). The formaldehyde concentration levels in ambient air at the measurement site are produced mainly by the photochemical oxidation of volatile organic compounds (VOCs) caused by intense sunlight during periods I and II. This observation was made based on a comparison with the ozone concentration, solar radiation, temperature, relative humidity, and wind speed data obtained from the Texas Commission on Environmental Quality (TCEQ). During period III, data collected by a time-integrating wet-chemical technique are compared to the data collected by the spectroscopic instrument.
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Affiliation(s)
- Jinhai Chen
- Department of Chemistry, Rice University, 6100 Main St., Houston, Texas 77005, USA
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Martin RV. Evaluation of GOME satellite measurements of tropospheric NO2and HCHO using regional data from aircraft campaigns in the southeastern United States. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2004jd004869] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Li YQ. Measurement of formaldehyde, nitrogen dioxide, and sulfur dioxide at Whiteface Mountain using a dual tunable diode laser system. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003jd004091] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Martinez M. OH and HO2concentrations, sources, and loss rates during the Southern Oxidants Study in Nashville, Tennessee, summer 1999. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2003jd003551] [Citation(s) in RCA: 145] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Fried A. Airborne tunable diode laser measurements of formaldehyde during TRACE-P: Distributions and box model comparisons. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2003jd003451] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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