My research is in the field of environmental mineralogy and geochemistry, focusing on the fate and transport of metals and radionuclides in the environment. In particular, I am interested in the geochemical and biogeochemical processes that occur at mineral surfaces which can limit or promote contaminant transport in a range of surface environments. My research has ranged from applied characterization studies of uranium and copper speciation at the U.S. Department of Energy's Hanford Site, to fundamental studies of the processes by which uranium and strontium are sequestered at mineral surfaces. Recent work has aimed at determining the mechanisms by which heavy metals or radionuclides can interact with complex mineral interfaces, in particular focusing on the formation of uranium-bearing nanoparticles. This work is done by applying laboratory-based analytical and microscopy tools and synchrotron-based X-ray spectroscopic and scattering methods to investigate natural and model systems.
Current and future research interests include:
- Electron transfer reactions between aqueous contaminants and mineral surfaces
- Metal sorption and diffusion kinetics into mesoporous materials
- Laboratory- and field-scale testing of metal remediation and stabilization techniques
Scholarly, Creative & Professional Activities
Singer, D. M., Chatman, S. M.; Ilton, E. S., Rosso, K. M., Banfield, J. F., Waychunas, G. A., (2012) U(VI) Sorption and Reduction Kinetics on the Magnetite (111) Surface. Environmental Science & Technology 2012, 46, (7), 3821-3830.
Singer, D. M.; Chatman, S. M., Ilton, E. S., Rosso, K. M., Banfield, J. F., Waychunas, G. A., (2012) Identification of Simultaneous U(VI) Sorption Complexes and U(IV) Nanoprecipitates on the Magnetite (111) Surface. Environmental Science & Technology 2012, 46, (7), 3811-3820.
Singer D. M., Maher K., and Brown, G.E. Jr. (2009) Uranyl-chlorite sorption/desorption: Evaluation of different U(VI) sequestration processes. Geochim. Cosmochim. Acta 73, 5989-6007.
Kelsey K. E., Stebbins J. F., Singer D. M., Brown G. E. Jr., Mosenfelder J. L., and Asimow P. D. (2009) Cation field strength effects on high pressure aluminosilicate glass structure: Multinuclear NMR and La XAFS results. Geochim. Cosmochim. Acta 73, 3914-3933.
Singer D. M., Farges F., and Brown G. E. Jr. (2009) Biogenic nanoparticulate UO2: Synthesis, characterization, and factors affecting surface reactivity. Geochim. Cosmochim. Acta 73, 3593-3611.
Singer D. M., Zachara J. M., and Brown G. E. Jr. (2009) Uranium speciation as a function of depth in contaminated Hanford sediments - A micro-XRF, micro-XRD, and micro- and bulk-XAFS Study. Environ. Sci. Technol. 43, 630-636.
Singer D. M., Johnson S. B., Catalano J. G., Farges F., and Brown G. E. Jr. (2008) Sequestration of Sr(II) by calcium oxalate - A batch uptake study and EXAFS analysis of model compounds and reaction products. Geochim. Cosmochim. Acta 72(20), 5055-5069.
Singer D. M., Farges F., and Brown G. E. Jr. (2007) Biogenic UO2 - characterization and surface reactivity. Am. Inst. Phys. Conf. Proc., 13th Int. XAFS Conf. 882(1), 277-279.
- Environmental Mineralogy
- Environmental Geochemistry
- Medical Geology
OFFICEDepartment of Geology
Center for Ecology and Natural Resources Sustainability
Spring 2014 Office Hours:
McGilvrey Hall 211
Tuesday and Thursday
8:00 - 10:00 am
or by appointment
CONTACT INFOPhone: 330-672-3006