1
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Linek A, Morzyński P, Witkowski M. Absolute frequency measurement of the 6s 21S 0 → 6s6p 3P 1F = 3/2 → F' = 5/2 201Hg transition with background-free saturation spectroscopy. OPTICS EXPRESS 2022; 30:44103-44117. [PMID: 36523093 DOI: 10.1364/oe.475986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 10/28/2022] [Indexed: 06/17/2023]
Abstract
We report the development of a method for eliminating background-induced systematic shifts affecting precise measurements of saturation absorption signals. With this technique, we measured the absolute frequency of the 6s21S0 → 6s6p3P1 transition in 201aHg (F = 3/2 → F' = 5/2) to be 1181541111051(83) kHz. The measurement was referenced with an optical frequency comb synchronized to the frequency of the local representation of the UTC. This specific atomic line is situated on the steep slope of the Doppler background at room temperature, which results in a frequency systematic shift. We determined the dependence of this shift on the properties of both the spectral line and the background of the measured signal.
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2
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Srivastava A, Hodges JT. Primary Measurement of Gaseous Elemental Mercury Concentration with a Dynamic Range of Six Decades. Anal Chem 2022; 94:15818-15826. [DOI: 10.1021/acs.analchem.2c03622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Abneesh Srivastava
- Chemical Sciences Division, Material Measurement Laboratory, National Institute of Standards and Technology (NIST), 100 Bureau Drive, Gaithersburg, Maryland20899, United States
| | - Joseph T. Hodges
- Chemical Sciences Division, Material Measurement Laboratory, National Institute of Standards and Technology (NIST), 100 Bureau Drive, Gaithersburg, Maryland20899, United States
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3
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Matsumoto N, Itoh N, Yamasaki K. Absolute Quantification of Pure Free Radical Reagents by Combination of the Effective Magnetic Moment Method and Quantitative Electron Paramagnetic Resonance Method. Anal Chem 2022; 94:12595-12603. [PMID: 36063091 DOI: 10.1021/acs.analchem.2c01005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An absolute quantitative analysis of free radicals by combining the effective magnetic moment method and the quantitative electron paramagnetic resonance [qEPR] method is proposed. This combined method utilizes the advantages of both the analytical methods and compensates for their disadvantages. In the effective magnetic moment method, the magnetic moment under a constant magnetic field is measured accurately using a superconducting quantum interference device. The qEPR method compares a "primary standard sample" and "secondary standard sample". The effective magnetic moment method was used to determine the purity of the primary standard sample. The qEPR method realizes a simple purity analysis of free-radical reagents with traceability to the International System of Units (SI). The purity of the free radicals by the qEPR method for pure 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl benzoate [4HTB], 1-oxyl-2,2,6,6-tetramethyl-4-hydroxypiperidine [TEMPOL], and di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium [DPPH] reagents was obtained with a relative expanded uncertainty of 0.7% for 4HTB to 1.5% for the DPPH. These small uncertainties were almost equal to those of the purity of the primary standard samples and were achieved by adopting in-plane positioning of the measured sample perpendicular to the cylindrical axis of the sample space of the superconducting quantum interference device. Some purity values of the free radicals for these reagents differed from those stated by the manufacturers. This combined method enables short-time quality control of pure radical reagents, instead of quality control by separation analytical methods or titrations.
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Affiliation(s)
- Nobuhiro Matsumoto
- National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), AIST Central-3, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8563, Japan
| | - Nobuyasu Itoh
- National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), AIST Central-3, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8563, Japan
| | - Kazuhiko Yamasaki
- Biomedical Research Institute (BMRI), National Institute of Advanced Industrial Science and Technology (AIST), AIST Central-6, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan
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4
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Gačnik J, Živković I, Ribeiro Guevara S, Kotnik J, Berisha S, Vijayakumaran Nair S, Jurov A, Cvelbar U, Horvat M. Calibration Approach for Gaseous Oxidized Mercury Based on Nonthermal Plasma Oxidation of Elemental Mercury. Anal Chem 2022; 94:8234-8240. [PMID: 35647905 PMCID: PMC9201811 DOI: 10.1021/acs.analchem.2c00260] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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Atmospheric mercury
measurements carried out in the recent decades
have been a subject of bias largely due to insufficient consideration
of metrological traceability and associated measurement uncertainty,
which are ultimately needed for the demonstration of comparability
of the measurement results. This is particularly challenging for gaseous
HgII species, which are reactive and their ambient concentrations
are very low, causing difficulties in proper sampling and calibration.
Calibration for atmospheric HgII exists, but barriers to
reliable calibration are most evident at ambient HgII concentration
levels. We present a calibration of HgII species based
on nonthermal plasma oxidation of Hg0 to HgII. Hg0 was produced by quantitative reduction of HgII in aqueous solution by SnCl2 and aeration. The
generated Hg0 in a stream of He and traces of reaction
gas (O2, Cl2, or Br2) was then oxidized
to different HgII species by nonthermal plasma. A highly
sensitive 197Hg radiotracer was used to evaluate the oxidation
efficiency. Nonthermal plasma oxidation efficiencies with corresponding
expanded standard uncertainty values were 100.5 ± 4.7% (k = 2) for 100 pg of HgO, 96.8 ± 7.3% (k = 2) for 250 pg of HgCl2, and 77.3 ± 9.4% (k = 2) for 250 pg of HgBr2. The presence of HgO,
HgCl2, and HgBr2 was confirmed by temperature-programmed
desorption quadrupole mass spectrometry (TPD-QMS). This work demonstrates
the potential for nonthermal plasma oxidation to generate reliable
and repeatable amounts of HgII compounds for routine calibration
of ambient air measurement instrumentation.
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Affiliation(s)
- Jan Gačnik
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia.,Jožef Stefan International Postgraduate School, Jamova Cesta 39, 1000 Ljubljana, Slovenia
| | - Igor Živković
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia
| | - Sergio Ribeiro Guevara
- Laboratorio de Análisis por Activación Neutrónica, Centro Atómico Bariloche, Av. Bustillo km 9.5, 8400 Bariloche, Argentina
| | - Jože Kotnik
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia.,Jožef Stefan International Postgraduate School, Jamova Cesta 39, 1000 Ljubljana, Slovenia
| | - Sabina Berisha
- Jožef Stefan International Postgraduate School, Jamova Cesta 39, 1000 Ljubljana, Slovenia
| | - Sreekanth Vijayakumaran Nair
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia.,Jožef Stefan International Postgraduate School, Jamova Cesta 39, 1000 Ljubljana, Slovenia
| | - Andrea Jurov
- Department of Gaseous Electronics, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia
| | - Uroš Cvelbar
- Jožef Stefan International Postgraduate School, Jamova Cesta 39, 1000 Ljubljana, Slovenia.,Department of Gaseous Electronics, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia
| | - Milena Horvat
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia.,Jožef Stefan International Postgraduate School, Jamova Cesta 39, 1000 Ljubljana, Slovenia
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5
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Kuwahara A, Aiba Y, Matsui M. Plasma Atomization of Strontium Chloride Powder by a Supersonic Plasma Jet and Measurement of Its Efficiency Using Diode Laser Absorption Spectroscopy. ACS OMEGA 2021; 6:11750-11755. [PMID: 34056328 PMCID: PMC8153998 DOI: 10.1021/acsomega.1c01094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 04/12/2021] [Indexed: 06/12/2023]
Abstract
Direct elemental and isotope analyses of solid samples have attracted considerable interest due to their potential role in preventing serious accidents at nuclear facilities. We previously developed an analytical method for detecting radioactive isotopes, combining diode laser absorption spectroscopy with a supersonic plasma jet. Its basic performance, that is, the detection limit as well as the translational temperature upstream and downstream of the supersonic nozzle, was investigated using stable Xe isotopes. The developed apparatus could atomize a solid sample and reduce the translational temperature for isotope identification. For direct isotope analysis, translational temperature and atomization efficiency during powder feeding are remarkably important. In the present study, a novel approach for the atomization of Sr powder samples containing isotopes with highly radiotoxic radionuclides is described. We found that the temperature of Sr atoms in the supersonic plasma jet decreased to approximately 85 K, which is comparable with the slight isotope shift of 88Sr-90Sr due to the difference in mass number. Moreover, based on the measured atomic number density and flow velocity, the atomization efficiency was found to be 10.4 ± 1.8%. The results of this study and further improvements in the efficiency can lead to the development of powerful tools for the rapid analysis of solid samples, particularly those contaminated with highly radioactive species, without the necessity for complex chemical separation.
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Affiliation(s)
- Akira Kuwahara
- Department
of Applied Energy, Nagoya University, Aichi 464-8603, Japan
- Department
of Decommissioning and Waste Management, Japan Atomic Energy Agency, Ibaraki 319-1195, Japan
| | - Yasuaki Aiba
- Department
of Engineering, Shizuoka University, Shizuoka 432-8561, Japan
| | - Makoto Matsui
- Department
of Engineering, Shizuoka University, Shizuoka 432-8561, Japan
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6
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Gačnik J, Živković I, Ribeiro Guevara S, Jaćimović R, Kotnik J, Horvat M. Validating an Evaporative Calibrator for Gaseous Oxidized Mercury. SENSORS 2021; 21:s21072501. [PMID: 33916694 PMCID: PMC8038396 DOI: 10.3390/s21072501] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/30/2021] [Accepted: 04/01/2021] [Indexed: 11/20/2022]
Abstract
Understanding atmospheric mercury chemistry is the key for explaining the biogeochemical cycle of mercury and for improving the predictive capability of computational models. Increased efforts are being made to ensure comparable Hg speciation measurements in the air through establishing metrological traceability. While traceability for elemental mercury has been recently set, this is by no means the case for gaseous oxidized mercury (GOM). Since a calibration unit suitable for traceable GOM calibrations based on evaporation of HgCl2 solution was recently developed, the purpose of our work was to extensively evaluate its performance. A highly specific and sensitive 197Hg radiotracer was used for validation over a wide range of concentrations. By comparing experimental and calculated values, we obtained recoveries for the calibration unit. The average recoveries ranged from 88.5% for 1178 ng m−3 HgCl2 gas concentration to 39.4% for 5.90 ng m−3 HgCl2 gas concentration. The losses were due to the adsorption of oxidized Hg on the inner walls of the calibrator and tubing. An adsorption isotherm was applied to estimate adsorption enthalpy (ΔHads); a ΔHads value of −12.33 kJ mol−1 was obtained, suggesting exothermal adsorption. The results of the calibrator performance evaluation suggest that a newly developed calibration unit is only suitable for concentrations of HgCl2 higher than 1 µg m−3. The concentration dependence of recoveries prevents the system from being used for calibration of instruments for ambient GOM measurements. Moreover, the previously assessed uncertainty of this unit at µg m−3 level (2.0%, k = 2) was re-evaluated by including uncertainty related to recovery and was found to be 4.1%, k = 2. Calibrator performance was also evaluated for HgBr2 gas calibration; the recoveries were much lower for HgBr2 gas than for HgCl2 gas even at a high HgBr2 gas concentration (>1 µg m−3). As HgBr2 is often used as a proxy for various atmospheric HgBr species, the suitability of the unit for such calibration must be further developed.
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Affiliation(s)
- Jan Gačnik
- Jožef Stefan International Postgraduate School, Jamova Cesta 39, 1000 Ljubljana, Slovenia;
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia; (I.Ž.); (R.J.); (J.K.)
| | - Igor Živković
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia; (I.Ž.); (R.J.); (J.K.)
| | - Sergio Ribeiro Guevara
- Laboratorio de Análisis por Activación Neutrónica, Centro Atómico Bariloche, Av. Bustillo km 9.5, Bariloche 8400, Argentina;
| | - Radojko Jaćimović
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia; (I.Ž.); (R.J.); (J.K.)
| | - Jože Kotnik
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia; (I.Ž.); (R.J.); (J.K.)
| | - Milena Horvat
- Jožef Stefan International Postgraduate School, Jamova Cesta 39, 1000 Ljubljana, Slovenia;
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia; (I.Ž.); (R.J.); (J.K.)
- Correspondence: ; Tel.: +386-1-588-53-55
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7
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Srivastava A, Long SE, Norris JE, Bryan CE, Carney J, Hodges JT. Comparison of Primary Laser Spectroscopy and Mass Spectrometry Methods for Measuring Mass Concentration of Gaseous Elemental Mercury. Anal Chem 2021; 93:1050-1058. [PMID: 33302624 PMCID: PMC8202126 DOI: 10.1021/acs.analchem.0c04002] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We present a direct comparison between two independent methods for the measurement of gaseous elemental mercury (GEM) mass concentration: isotope dilution cold-vapor inductively coupled plasma mass spectrometry (ID-CV-ICP-MS) and laser absorption spectroscopy (LAS). The former technique combined with passive sorbent tube sampling is currently the primary method at NIST for mercury gas standards traceability to the International System of Units (SI). This traceability is achieved via measurements on a mercury-containing reference material. The latter technique has been recently developed at NIST and involves real-time measurements of light attenuation caused by GEM, with SI traceability based in part on the known spontaneous emission lifetime of the probed 6 1S0-6 3P1 intercombination transition of elemental mercury (Hg0). Using a steady-flow Hg0-in-air generator to produce samples measured by both methods, we use LAS to measure the sample gas and in parallel we collect the Hg0 on sorbent tubes to be subsequently analyzed using ID-CV-ICP-MS. Over the examined mass concentration range (41 μg/m3 to 287 μg/m3 Hg0 in air), the relative disagreement between the two approaches ranged from (1.0 to 1.8)%. The relative combined standard uncertainty on average is 0.4% and 0.9%, for the LAS and MS methods, respectively. Our comparison studies help validate the accuracy of the ID-CV-ICP-MS primary method as well as establish the LAS technique as an attractive alternative primary method for SI-traceable measurements of GEM.
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Affiliation(s)
- Abneesh Srivastava
- Chemical Sciences Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899-8393, United States
| | - Stephen E. Long
- Chemical Sciences Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899-8393, United States
| | - James E. Norris
- Chemical Sciences Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899-8393, United States
| | - Colleen E. Bryan
- Chemical Sciences Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899-8393, United States
| | - Jennifer Carney
- Chemical Sciences Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899-8393, United States
| | - Joseph T. Hodges
- Chemical Sciences Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899-8393, United States
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8
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Lyman SN, Gratz LE, Dunham-Cheatham SM, Gustin MS, Luippold A. Improvements to the Accuracy of Atmospheric Oxidized Mercury Measurements. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:13379-13388. [PMID: 33075225 DOI: 10.1021/acs.est.0c02747] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We developed a cation-exchange membrane-based dual-channel system to measure elemental and oxidized mercury and deployed it with an automated calibration system and the University of Nevada, Reno-Reactive Mercury Active System (UNR-RMAS) at a rural/suburban field site in Colorado during the summer of 2018. Unlike oxidized mercury measurements collected via the widely used KCl denuder method, the dual-channel system was able to quantitatively recover HgCl2 and HgBr2 injected by the calibrator into the ambient sample air and compared well with the UNR-RMAS measurements. The system measured at 10 min intervals and had a 3-h average detection limit for oxidized mercury of 33 pg m-3. It was able to detect day-to-day variability and diel cycles in oxidized mercury (0 to 200 pg m-3) and will be an important tool for future studies of atmospheric mercury. We used a gravimetric method to independently determine the total mercury permeation rate from the permeation tubes. Permeation rates derived from the gravimetric method matched the permeation rates observed via mercury measurement devices to within 25% when the mercury permeation rate was relatively high (up to 30 pg s-1), but the agreement decreased for lower permeation rates, probably because of increased uncertainty in the gravimetric measurements.
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Affiliation(s)
- Seth N Lyman
- Bingham Research Center, Utah State University, Vernal, Utah 84078, United States
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0305, United States
| | - Lynne E Gratz
- Environmental Studies Program, Colorado College, Colorado Springs, Colorado 80903-3298, United States
| | - Sarrah M Dunham-Cheatham
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, Reno, Nevada 89557, United States
| | - Mae Sexauer Gustin
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, Reno, Nevada 89557, United States
| | - Adriel Luippold
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, Reno, Nevada 89557, United States
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9
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Sommar J, Osterwalder S, Zhu W. Recent advances in understanding and measurement of Hg in the environment: Surface-atmosphere exchange of gaseous elemental mercury (Hg 0). THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 721:137648. [PMID: 32182462 DOI: 10.1016/j.scitotenv.2020.137648] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 02/26/2020] [Accepted: 02/28/2020] [Indexed: 05/26/2023]
Abstract
The atmosphere is the major transport pathway for distribution of mercury (Hg) globally. Gaseous elemental mercury (GEM, hereafter Hg0) is the predominant form in both anthropogenic and natural emissions. Evaluation of the efficacy of reductions in emissions set by the UN's Minamata Convention (UN-MC) is critically dependent on the knowledge of the dynamics of the global Hg cycle. Of these dynamics including e.g. red-ox reactions, methylation-demethylation and dry-wet deposition, poorly constrained atmosphere-surface Hg0 fluxes especially limit predictability of the timescales of its global biogeochemical cycle. This review focuses on Hg0 flux field observational studies, namely the theory, applications, strengths, and limitations of the various experimental methodologies applied to gauge the exchange flux and decipher active sub-processes. We present an in-depth review, a comprehensive literature synthesis, and methodological and instrumentation advances for terrestrial and marine Hg0 flux studies in recent years. In particular, we outline the theory of a wide range of measurement techniques and detail the operational protocols. Today, the most frequently used measurement techniques to determine the net Hg0 flux (>95% of the published flux data) are dynamic flux chambers for small-scale and micrometeorological approaches for large-scale measurements. Furthermore, top-down approaches based on Hg0 concentration measurements have been applied as tools to better constrain Hg emissions as an independent way to e.g. challenge emission inventories. This review is an up-dated, thoroughly revised edition of Sommar et al. 2013 (DOI: 10.1080/10643389.2012.671733). To the tabulation of >100 cited flux studies 1988-2009 given in the former publication, we have here listed corresponding studies published during the last decade with a few exceptions (2008-2019). During that decade, Hg stable isotope ratios of samples involved in atmosphere-terrestrial interaction is at hand and provide in combination with concentration and/or flux measurements novel constraints to quantitatively and qualitatively assess the bi-directional Hg0 flux. Recent efforts in the development of relaxed eddy accumulation and eddy covariance Hg0 flux methods bear the potential to facilitate long-term, ecosystem-scale flux measurements to reduce the prevailing large uncertainties in Hg0 flux estimates. Standardization of methods for Hg0 flux measurements is crucial to investigate how land-use change and how climate warming impact ecosystem-specific Hg0 sink-source characteristics and to validate frequently applied model parameterizations describing the regional and global scale Hg cycle.
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Affiliation(s)
- Jonas Sommar
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China.
| | - Stefan Osterwalder
- Institut des Géosciences de l'Environnement, Université Grenoble Alpes, CNRS, IRD, Grenoble INP, Grenoble, France
| | - Wei Zhu
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
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10
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Zhang T, Lou X, Xu L, He S. Elemental mercury sensing by synchronously sweeping two multimode diode lasers. APPLIED OPTICS 2020; 59:3360-3368. [PMID: 32400446 DOI: 10.1364/ao.386105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 02/28/2020] [Indexed: 06/11/2023]
Abstract
We propose a sum-frequency-generation (SFG) laser-based elemental mercury sensing method by mixing two low-cost multimode diode lasers (MDLs). The wavelengths of the two MDLs are synchronously scanned, which enlarges the whole coverage range of wavelength and improves the measurement stability. Correlation spectroscopy was used to eliminate the impact of environmental change and enhance and trace the absorption signal of the sample accurately. A novel data processing method was employed to extract the weak absorption signals from the background efficiently. A sensitivity of ${0.1}\;\unicode{x00B5} {{\rm g/m}^3}$0.1µg/m3 (11 ppt) was achieved for 1-m path length and 10-s integration time. The sensing range was efficiently increased up to ${200}\;\unicode{x00B5} {{\rm g/m}^3}$200µg/m3 using a calibration curve based on a new mathematical analytical formula. Real-time monitoring of the mercury volatilization and diffusion process was experimentally demonstrated with a time resolution of 10 s. The performance of the system shows great practical value for the detection of elemental mercury in industrial applications.
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11
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Lyman SN, Cheng I, Gratz LE, Weiss-Penzias P, Zhang L. An updated review of atmospheric mercury. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 707:135575. [PMID: 31784172 DOI: 10.1016/j.scitotenv.2019.135575] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 11/14/2019] [Accepted: 11/15/2019] [Indexed: 06/10/2023]
Abstract
The atmosphere is a key component of the biogeochemical cycle of mercury, acting as a reservoir, transport mechanism, and facilitator of chemical reactions. The chemical and physical behavior of atmospheric mercury determines how, when, and where emitted mercury pollution impacts ecosystems. In this review, we provide current information about what is known and what remains uncertain regarding mercury in the atmosphere. We discuss new ambient, laboratory, and theoretical information about the chemistry of mercury in various atmospheric media. We review what is known about mercury in and on solid- and liquid-phase aerosols. We present recent findings related to wet and dry deposition and spatial and temporal trends in atmospheric mercury concentrations. We also review atmospheric measurement methods that are in wide use and those that are currently under development.
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Affiliation(s)
- Seth N Lyman
- Bingham Research Center, Utah State University, 320 N Aggie Blvd., Vernal, UT, USA; Department of Chemistry and Biochemistry, Utah State University, 4820 Old Main Hill, Logan, UT, USA.
| | - Irene Cheng
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin St., Toronto, Ontario, Canada
| | - Lynne E Gratz
- Environmental Studies Program, Colorado College, 14 East Cache la Poudre St., Colorado Springs, CO, USA
| | - Peter Weiss-Penzias
- Chemistry and Biochemistry Department, University of California, Santa Cruz, 1156 High St, Santa Cruz, CA, USA; Microbiology and Environmental Toxicology Department, University of California, Santa Cruz, 1156 High St, Santa Cruz, CA, USA
| | - Leiming Zhang
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin St., Toronto, Ontario, Canada
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