Speciation mapping of environmental samples using XANES imaging
Barbara E. Etschmann A B , Erica Donner C D , Joël Brugger E , Daryl L. Howard F , Martin D. de Jonge F , David Paterson F , Ravi Naidu C D , Kirk G. Scheckel G , Chris G. Ryan H and Enzo Lombi C IA Mineralogy, South Australian Museum, North Terrace, Adelaide, GPO Box 234, SA 5001, Australia.
B School of Chemical Engineering, University of Adelaide, North Terrace, Adelaide, SA 5005, Australia.
C Centre for Environmental Risk Assessment and Remediation, University of South Australia, Building X, Mawson Lakes Campus, SA 5095, Australia.
D CRC CARE, PO Box 486, Salisbury, SA 5106, Australia.
E School of Geosciences, Monash University, Building 28, Clayton, Vic. 3800, Australia
F Australian Synchrotron, 800 Blackburn Road, Clayton, Vic. 3168, Australia
G US Environmental Protection Agency, Office of Research and Development, 5995 Center Hill Avenue, Cincinnati, OH 45224-1702, USA.
H Earth Science and Resource Engineering, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Bayview Avenue, Clayton, Vic. 3168, Australia.
I Corresponding author: enzo.lombi@unisa.edu.au
Environmental Chemistry 11(3) 341-350 https://doi.org/10.1071/EN13189
Submitted: 15 October 2013 Accepted: 28 February 2014 Published: 5 June 2014
Environmental context. Recently developed fast fluorescence detectors have opened the way to the development of element speciation mapping, i.e. X-ray absorption near edge spectroscopy (XANES) imaging, of environmental samples. This technique is potentially very informative but is also highly data intensive. Here, we used XANES imaging to explore the distribution of Cu species in biosolid materials, destined for agricultural use, as this is of importance in relation to the bioavailability and potential toxicity of this metal.
Abstract. Fast X-ray detectors with large solid angles and high dynamic ranges open the door to XANES imaging, in which millions of spectra are collected to image the speciation of metals at micrometre resolution, over areas up to several square centimetres. This paper explores how such multispectral datasets can be analysed in order to provide further insights into the distribution of Cu species in fresh and stockpiled biosolids. The approach demonstrated uses Principal Components Analysis to extract the ‘significant’ spectral information from the XANES maps, followed by cluster analysis to locate regions of contrasting spectral signatures. Following this model-free analysis, pixel-by-pixel linear combination fits are used to provide a direct link between bulk and imaging XANES spectroscopy. The results indicate that both the speciation and distribution of Cu species are significantly affected by ageing. The majority of heterogeneously distributed micrometre-sized Cu sulfide particles present in fresh biosolids disappear during the oxidative stockpiling process. In aged biosolids most of the Cu is homogeneously redistributed on organic matter suggesting that Cu mobility is temporarily increased during this redistribution process. This manuscript demonstrates how large XANES imaging datasets could be analysed and used to gain a deep understanding of metal speciation in environmental samples.
Additional keywords: agriculture, biosolids, copper.
References
[1] E. Lombi, J. Susini, Synchrotron-based techniques for plant and soil science: opportunities, challenges and future perspectives. Plant Soil 2009, 320, 1.| Synchrotron-based techniques for plant and soil science: opportunities, challenges and future perspectives.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXmvFGjtLo%3D&md5=620f8be30a63879688ab9f76568d105eCAS |
[2] A. Manceau, M. C. Boisset, G. Sarret, R. L. Hazemann, M. Mench, P. Cambier, R. Prost, Direct determination of lead speciation in contaminated soils by EXAFS spectroscopy. Environ. Sci. Technol. 1996, 30, 1540.
| Direct determination of lead speciation in contaminated soils by EXAFS spectroscopy.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28XhvVKgt70%3D&md5=b729fe61c1c989e1633c56e70b4bc711CAS |
[3] J. Brugger, B. Etschmann, M. Pownceby, W. Liu, P. Grundler, D. Brewe, Tracking the chemistry of ancient fluids: oxidation state of europium in hydrothermal scheelite. Chem. Geol. 2008, in press.
| Tracking the chemistry of ancient fluids: oxidation state of europium in hydrothermal scheelite.Crossref | GoogleScholarGoogle Scholar |
[4] S. Behrens, A. Kappler, M. Obst, Linking environmental processes to the in situ functioning of microorganisms by high-resolution secondary ion mass spectrometry (NanoSIMS) and scanning transmission X-ray microscopy (STXM). Environ. Microbiol. 2012, 14, 2851.
| Linking environmental processes to the in situ functioning of microorganisms by high-resolution secondary ion mass spectrometry (NanoSIMS) and scanning transmission X-ray microscopy (STXM).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XhsFGqt7bL&md5=f956ffc94e2bfc2d28d0e9eed5b8d041CAS | 22409443PubMed |
[5] M. Muñoz, V. De Andrade, O. Vidal, E. Lewin, S. Pascarelli, J. Susini, Redox and speciation micromapping using dispersive X-ray absorption spectroscopy: application to iron chlorite mineral of a metamorphic rock thin section. Geochem. Geophys. Geosyst. 2006, 7, Q11020.
| Redox and speciation micromapping using dispersive X-ray absorption spectroscopy: application to iron chlorite mineral of a metamorphic rock thin section.Crossref | GoogleScholarGoogle Scholar |
[6] G. Martínez-Criado, A. Somogyi, A. Homs, R. Tucoulou, J. Susini, Micro-X-ray absorption near-edge structure imaging for detecting metallic Mn in GaN. Appl. Phys. Lett. 2005, 87, 061913.
| Micro-X-ray absorption near-edge structure imaging for detecting metallic Mn in GaN.Crossref | GoogleScholarGoogle Scholar |
[7] M. A. Denecke, A. Somogyi, K. Janssens, R. Simon, K. Dardenne, U. Noseck, Microanalysis (micro-XRF, micro-XANES, and micro-XRD) of a tertiary sediment using microfocused synchrotron radiation. Microsc. Microanal. 2007, 13, 165.
| Microanalysis (micro-XRF, micro-XANES, and micro-XRD) of a tertiary sediment using microfocused synchrotron radiation.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXmsl2js7o%3D&md5=5b78dc39f6536685aa3519daff9355f2CAS | 17490498PubMed |
[8] L. E. Mayhew, S. M. Webb, A. S. Templeton, Microscale imaging and identification of Fe speciation and distribution during fluid–mineral reactions under highly reducing conditions. Environ. Sci. Technol. 2011, 45, 4468.
| Microscale imaging and identification of Fe speciation and distribution during fluid–mineral reactions under highly reducing conditions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXltFajtLw%3D&md5=42ba32ddf8efc3df136ad89a2cee0811CAS | 21517061PubMed |
[9] C. G. Ryan, D. P. Siddons, G. Moorhead, R. Kirkham, G. De Geronimo, B. E. Etschmann, A. Dragone, P. A. Dunn, A. Kuczewski, P. Davey, M. Jensen, J. M. Ablett, J. Kuczewski, R. Hough, D. Patersons, High-throughput X-ray fluorescence imaging using a massively parallel detector array, integrated scanning and real-time spectral deconvolution. J. Phys. Conf. Ser. 2009, 186, 012013.
| High-throughput X-ray fluorescence imaging using a massively parallel detector array, integrated scanning and real-time spectral deconvolution.Crossref | GoogleScholarGoogle Scholar |
[10] E. Lombi, M. D. de Jonge, E. Donner, C. G. Ryan, D. Paterson, Trends in hard X-ray fluorescence mapping: environmental applications in the age of fast detectors. Anal. Bioanal. Chem. 2011, 400, 1637.
| Trends in hard X-ray fluorescence mapping: environmental applications in the age of fast detectors.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXjtVOns7o%3D&md5=249489e3082ba79690ce1ead8a45496aCAS | 21390564PubMed |
[11] C. G. Ryan, D. P. Siddons, R. Kirkham, Z. Y. Li, M. D. de Jonge, D. J. Paterson, A. Kuczewski, D. L. Howard, P. A. Dunn, G. Falkenberg, U. Boesenberg, G. De Geronimo, L. A. Fisher, A. Halfpenny, M. J. Lintern, E. Lombi, K. A. Dyl, M. Jensen, G. F. Moorhead, J. S. Cleverley, R. M. Hough, B. Godel, S. J. Barnes, S. A. James, K. M. Spiers, M. Alfeld, G. Wellenreuther, Z. Vukmanovic, S. Borg, MAIA X-ray fluorescence imaging: capturing detail in complex natural samples. J. Phys. Conf. Ser. 2014, 499, 012002.
| MAIA X-ray fluorescence imaging: capturing detail in complex natural samples.Crossref | GoogleScholarGoogle Scholar |
[12] B. E. Etschmann, C. G. Ryan, J. Brugger, R. Kirkham, R. M. Hough, G. Moorhead, D. P. Siddons, G. De Geronimo, A. Kuczewski, P. Dunn, D. Paterson, M. D. de Jonge, D. L. Howard, P. Davey, M. Jensen, Reduced As components in highly oxidized environments: evidence from full spectral XANES imaging using the MAIA massively parallel detector. Am. Mineral. 2010, 95, 884.
| Reduced As components in highly oxidized environments: evidence from full spectral XANES imaging using the MAIA massively parallel detector.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXmslKksLg%3D&md5=04d5b580c649f0654432b1f7518f3caaCAS |
[13] E. Donner, D. L. Howard, M. D. de Jonge, D. Paterson, M. H. Cheah, R. Naidu, E. Lombi, X-Ray absorption and micro X-ray fluorescence spectroscopy investigation of copper and zinc speciation in biosolids. Environ. Sci. Technol. 2011, 45, 7249.
| X-Ray absorption and micro X-ray fluorescence spectroscopy investigation of copper and zinc speciation in biosolids.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhtVWntrfI&md5=a749b922f0fb1a84fd75ec3a31aed6b8CAS | 21793501PubMed |
[14] N. T. Basta, J. A. Ryan, R. L. Chaney, Trace element chemistry in residual-treated soil: key concepts and metal bioavailability. J. Environ. Qual. 2005, 34, 49.
| 1:CAS:528:DC%2BD2MXotlSjsw%3D%3D&md5=822f88f11663ce9dd1b7cd95bb8a87ccCAS | 15647534PubMed |
[15] E. Smolders, K. Oorts, P. van Sprang, I. Schoeters, C. R. Janssen, S. P. McGrath, M. J. McLaughlin, Toxicity of trace metals in soil as affected by soil type and aging after contamination: using calibrated bioavailability models to set ecological soil standards. Environ. Toxicol. Chem. 2009, 28, 1633.
| Toxicity of trace metals in soil as affected by soil type and aging after contamination: using calibrated bioavailability models to set ecological soil standards.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXovFertr4%3D&md5=8ca9c07aa1948537f7ea565911209346CAS | 19301943PubMed |
[16] M. B. McBride, Toxic metal accumulation from agricultural use of sludge – are USEPA regulations protective? J. Environ. Qual. 1995, 24, 5.
| Toxic metal accumulation from agricultural use of sludge – are USEPA regulations protective?Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXjtVeqt70%3D&md5=e4c5f9220084e1b58925a722c37ff7ceCAS |
[17] S. L. Brown, R. L. Chaney, J. S. Angle, J. A. Ryan, The phytoavailability of cadmium to lettuce in long-term biosolids-amended soils. J. Environ. Qual. 1998, 27, 1071.
| The phytoavailability of cadmium to lettuce in long-term biosolids-amended soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXmtl2js7s%3D&md5=d69b9039654abbe74a0b08615f5bbf71CAS |
[18] A. Chaudri, S. McGrath, P. Gibbs, B. Chambers, C. Carlton-Smith, A. Godley, J. Bacon, C. Campbell, M. Aitken, Cadmium availability to wheat grain in soils treated with sewage sludge or metal salts. Chemosphere 2007, 66, 1415.
| Cadmium availability to wheat grain in soils treated with sewage sludge or metal salts.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XhtlSiu7jF&md5=ac5eda94f67b24a9308022453d74a5bbCAS | 17109920PubMed |
[19] D. A. Heemsbergen, M. J. McLaughlin, M. Whatmuff, M. S. Warne, K. Broos, M. Bell, D. Nash, G. Barry, D. Pritchard, N. Penney, Bioavailability of zinc and copper in biosolids compared to their soluble salts. Environ. Pollut. 2010, 158, 1907.
| Bioavailability of zinc and copper in biosolids compared to their soluble salts.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXmt1Kmt70%3D&md5=0c10e03160e7e63910655cb327fc8835CAS | 19932536PubMed |
[20] U. Kukier, R. L. Chaney, J. A. Ryan, W. L. Daniels, R. H. Dowdy, T. C. Granato, Phytoavailability of cadmium in long-term biosolids-amended soils. J. Environ. Qual. 2010, 39, 519.
| Phytoavailability of cadmium in long-term biosolids-amended soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXjsFCquro%3D&md5=48d59c2b87017de32492ea66ea28617cCAS | 20176825PubMed |
[21] E. Smolders, K. Oorts, E. Lombi, I. Schoeters, Y. B. Ma, S. Zrna, M. J. McLaughlin, The availability of copper in soils historically amended with sewage sludge, manure, and compost. J. Environ. Qual. 2012, 41, 506.
| The availability of copper in soils historically amended with sewage sludge, manure, and compost.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38Xkt1yluro%3D&md5=dcc3a36d86f6dc6924dce7e0a87d63dcCAS | 22370413PubMed |
[22] E. Lombi, R. Sekine, E. Donner, Synchrotron biogeochemistry: piecing together the ever increasing details of the large puzzle. Environ. Chem. 2014, 11, 1.
| Synchrotron biogeochemistry: piecing together the ever increasing details of the large puzzle.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXjtFSiur4%3D&md5=6316d93dc5684019573d907050faeb68CAS |
[23] M. Lerotic, C. Jacobsen, T. Schafer, S. Vogt, Cluster analysis of soft X-ray spectromicroscopy data. Ultramicroscopy 2004, 100, 35.
| Cluster analysis of soft X-ray spectromicroscopy data.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXltF2lsr4%3D&md5=09fe2c212ea09a582d891c8bcfc581fcCAS | 15219691PubMed |
[24] M. Lerotic, C. Jacobsen, J. B. Gillow, A. J. Francis, S. Wirick, S. Vogt, J. Maser, Cluster analysis in soft X-ray spectromicroscopy: finding the patterns in complex specimens. J. Electron Spectrosc. Relat. Phenom. 2005, 144–147, 1137.
| Cluster analysis in soft X-ray spectromicroscopy: finding the patterns in complex specimens.Crossref | GoogleScholarGoogle Scholar |
[25] D. Paterson, M. D. de Jonge, D. L. Howard, W. Lewis, J. McKinlay, A. Starritt, M. Kusel, C. G. Ryan, R. Kirkham, G. Moorhead, D. P. Siddons, The X-ray fluorescence microscopy beamline at the Australian synchrotron. AIP Conf. Proc. 2011, 1365, 219.
| The X-ray fluorescence microscopy beamline at the Australian synchrotron.Crossref | GoogleScholarGoogle Scholar |
[26] R. Kirkham, P. A. Dunn, A. J. Kuczewski, D. P. Siddons, R. Dodanwela, G. F. Moorhead, C. G. Ryan, G. De Geronimo, R. Beuttenmuller, D. Pinelli, M. Pfeffer, P. Davey, M. Jensen, D. J. Paterson, M. D. de Jonge, D. L. Howard, M. Kuesel, J. McKinlay, The MAIA spectroscopy detector system: engineering for integrated pulse capture, low-latency scanning and real-time processing. AIP Conf. Proc. 2010, 1234, 240.
| The MAIA spectroscopy detector system: engineering for integrated pulse capture, low-latency scanning and real-time processing.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXos1CksLk%3D&md5=f2e8794416c63da0908c567b0df60d42CAS |
[27] C. G. Ryan, Quantitative trace element imaging using PIXE and the nuclear microprobe. Int. J. Imaging Syst. Technol. 2000, 11, 219.
| Quantitative trace element imaging using PIXE and the nuclear microprobe.Crossref | GoogleScholarGoogle Scholar |
[28] C. G. Ryan, D. P. Siddons, R. Kirkham, P. A. Dunn, A. Kuczewski, G. Moorhead, G. De Geronimo, D. J. Paterson, M. D. de Jonge, R. M. Hough, M. J. Lintern, D. L. Howard, P. Kappen, J. Cleverley, The new MAIA detector system: methods for high definition trace element imaging of natural material. AIP Conf. Proc. 2010, 1221, 9.
| The new MAIA detector system: methods for high definition trace element imaging of natural material.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXkvFeju7g%3D&md5=75b2ccca697abbdc5ebcdb39b6253f49CAS |
[29] H. Ebel, R. Svagera, M. F. Ebel, A. Shaltout, J. H. Hubbell, Numerical description of photoelectric absorption coefficients for fundamental parameter programs. XRay Spectrom. 2003, 32, 442.
| Numerical description of photoelectric absorption coefficients for fundamental parameter programs.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXptVyksrk%3D&md5=36271124cc31a53975551c4c016c8648CAS |
[30] W. T. Elam, B. D. Ravel, J. R. Sieber, A new atomic database for X-ray spectroscopic calculations. Radiat. Phys. Chem. 2002, 63, 121.
| A new atomic database for X-ray spectroscopic calculations.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXptFSrsrY%3D&md5=d03cfbabfb9d04cef7f0006fb8fb3940CAS |
[31] C. G. Ryan, E. van Achterbergh, D. N. Jamieson, Advances in dynamic analysis PIXE imaging: correction for spatial variation of pile-up components. Nucl. Instrum. Methods Phys. Res. B 2005, 231, 162.
| Advances in dynamic analysis PIXE imaging: correction for spatial variation of pile-up components.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXktFWis74%3D&md5=0bba4bd3befb7b6484d061598ef9e7daCAS |
[32] C. G. Ryan, B. E. Etschmann, S. Vogt, J. Maser, C. Harland, E. van Achterbergh, D. Legnini, Nuclear microprobe – synchrotron synergy: towards integrated quantitative real-time elemental imaging using PIXE and SXRF. Nucl. Instrum. Meth. B 2005, 231, 183.
| Nuclear microprobe – synchrotron synergy: towards integrated quantitative real-time elemental imaging using PIXE and SXRF.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXktFWis70%3D&md5=76660debf4ab9a7bd079be494f38985dCAS |
[33] P. R. Bevington, Least-squares fit to an arbitrary function, in Data Reduction and Error Analysis for the Physical Sciences 1969, pp. 204–246 (McGraw-Hill Book Company: New York).
[34] N. R. Draper, H. Smith, An introduction to non-linear estimation, in Applied Regression Analysis 1966, pp. 263–307 (Wiley: New York).
[35] M. D. Abramoff, P. J. Magalhaes, S. J. Ram, Image processing with ImageJ. Biophotonics Int. 2004, 11, 36.
[36] C. A. Schneider, W. S. Rasband, K. W. Eliceiri, NIH Image to ImageJ: 25 years of image analysis. Nat. Methods 2012, 9, 671.
| NIH Image to ImageJ: 25 years of image analysis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XhtVKntb7P&md5=888169d431f644041ae9945173cb294dCAS | 22930834PubMed |
[37] B. Ravel, M. Newville, ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT. J. Synchrotron Radiat. 2005, 12, 537.
| ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXltlCntLo%3D&md5=38393bb2fbbd8e2e2db909c600fda025CAS | 15968136PubMed |
[38] T. A. Kirpichtchikova, A. Manceau, L. Spadini, F. Panfili, M. A. Marcus, T. Jacquet, Speciation and solubility of heavy metals in contaminated soil using X-ray microfluorescence, EXAFS spectroscopy, chemical extraction, and thermodynamic modeling. Geochim. Cosmochim. Acta 2006, 70, 2163.
| Speciation and solubility of heavy metals in contaminated soil using X-ray microfluorescence, EXAFS spectroscopy, chemical extraction, and thermodynamic modeling.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xjslyht7k%3D&md5=b2a83c83511b2db0ccc824530a980767CAS |
[39] B. Kim, C. S. Park, M. Murayama, M. F. Hochella, Discovery and characterization of silver sulfide nanoparticles in final sewage sludge products. Environ. Sci. Technol. 2010, 44, 7509.
| Discovery and characterization of silver sulfide nanoparticles in final sewage sludge products.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXhtFGhtr%2FL&md5=65fbaa4f818111971bc08296c239c594CAS | 20839838PubMed |
[40] S. Kelly, D. Hesterberg, B. Ravel, Analysis of soils and minerals using X-ray absorption spectroscopy, in Methods of Soil Analysis, Part 5. Mineralogical Methods 2008, Chapt. 14, pp. 387–463 (Soil Sciences Society of America: Madison, WI).
[41] G. M. Hettiarachchi, J. A. Ryan, R. L. Chaney, C. M. La Fleur, Sorption and desorption of cadmium by different fractions of biosolids-amended soils. J. Environ. Qual. 2003, 32, 1684.
| Sorption and desorption of cadmium by different fractions of biosolids-amended soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXnsFKmtbs%3D&md5=ce1845aa7983e4a970d5777a5488fa78CAS | 14535309PubMed |
[42] E. Donner, C. G. Ryan, D. L. Howard, B. Zarcinas, K. G. Scheckel, S. P. McGrath, M. D. de Jonge, D. Paterson, R. Naidu, E. Lombi, A multi-technique investigation of copper and zinc distribution, speciation and potential bioavailability in biosolids. Environ. Pollut. 2012, 166, 57.
| A multi-technique investigation of copper and zinc distribution, speciation and potential bioavailability in biosolids.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38Xms12gu70%3D&md5=6326c7841ca6a970d53c0ad0b5258abcCAS | 22475551PubMed |
[43] E. Donner, G. Brunetti, B. Zarcinas, P. Harris, E. Tavakkoli, R. Naidu, E. Lombi, Use of chemical amendments for immobilisation of metals in anarobically digested biosolids. Environ. Sci. Technol. 2013, 47, 11157.
| Use of chemical amendments for immobilisation of metals in anarobically digested biosolids.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXhtlektr%2FF&md5=b90c999e132f1c476a6372295913b7edCAS | 23981056PubMed |
[44] R. Kaegi, A. Voegelin, B. Sinnet, S. Zuleeg, H. Hagendorfer, M. Burkhardt, H. Siegrist, Behavior of metallic silver nanoparticles in a pilot wastewater treatment plant. Environ. Sci. Technol. 2011, 45, 3902.
| Behavior of metallic silver nanoparticles in a pilot wastewater treatment plant.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXkt1Cqtbc%3D&md5=735cc26c16080c1eca1bd0df25093c6dCAS | 21466186PubMed |
[45] E. Lombi, E. Donner, E. Tavakkoli, T. W. Turney, R. Naidu, B. W. Miller, K. G. Scheckel, Fate of zinc oxide nanoparticles during anaerobic digestion of wastewater and post-treatment processing of sewage sludge. Environ. Sci. Technol. 2012, 46, 9089.
| Fate of zinc oxide nanoparticles during anaerobic digestion of wastewater and post-treatment processing of sewage sludge.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XhtVKlt7%2FK&md5=a8ff12f656878e0da34540a48c78cc9fCAS | 22816872PubMed |
[46] M. Rivers, 4,000 Spectra or 4,000,000 ROIs per second: EPICS support for high-speed digital X-ray spectroscopy with the XIA xMap, in XRM 2010, 10th International Conference on X-ray Microscopy, 15–20 August 2010, Chicago, IL 2010 (Argonne National Laboratory: Argonne, IL, USA). [See also http://cars9.uchicago.edu/software/epics/dxp.html for DXP 3.0 release.]
[47] P. A. B. Scoullar, C. C. McLean, R. J. Evans, Real time pulse pile-up recovery in a high throughput digital pulse processor. AIP Conf. Proc. 2011, 1412, 270.
| Real time pulse pile-up recovery in a high throughput digital pulse processor.Crossref | GoogleScholarGoogle Scholar |