Assistant Professor 
School of Geology and Geophysics,
University of
Oklahoma
Postdoctoral
Research Associate, 2005-2007, Oak Ridge National Laboratory
Ph.D.
(geochemistry), 2005, Virginia Tech
B.S.
(geology), 2000, Michigan State University
NANOSCALE GEOSCIENCE and LOW-TEMPERATURE BIOGEOCHEMISTRY
My research interests and expertise lie in the exploration of nanoscale science in the natural world. This includes the interactions between minerals, water, and bacteria. Our group and collaborators look to share our results with educators through research experiences and paritipation in the Nano2Earth project.
I am co-director of the Physical and Environmental Geochemistry Laboratory with Dr. Megan Elwood Madden.
For examples of research facilites and projects, please visit the websites for the laboratories.
Current graduate students are Xiaofeng Chen (Ph.D., w/Reches), Matthew Kendall (M.S.), Matthew Miller (M.S.), and Andrew Swindle (Ph.D.).
EXAMPLES OF CURRENT RESEARCH PROJECTS
Imagine you are holding a crystal of hematite (iron oxide) in your hand, 1 cm on each side. You would like to know something about it, so you measure all of its properties that you can think of: it’s melting temperature, crystal structure, its color, its behavior in the presence of magnetic fields, and its chemical reactivity. Now imagine that the hematite is only 1 mm on a side. When you repeat the measurements, you are likely to get the same answers. Repeat the measurements again on a hematite crystal with 1 micron (1/1000 mm) length sides – once again, you get many of the same answers! Once the length scales of the crystal sides begins to shrink below 100 nanometers (1 nm = 1 billionth of a meter), some of those properties may start to change as a function of the crystal size. In fact, as the size of the crystal decreases towards 1 nm, more properties change at an increasingly rapid rate. The fundamental measurements that we know about this material, ‘hematite’, are no longer fixed- they’re a function of the particle size! Determining the properties of nanomaterials and how those properties change as a function of size is nanoscience.
In the Earth and environmental sciences, vast amounts of materials are found in the length scale of 1-100 nm that have novel properties because of their small size. These geologic nanomaterials may dissolve easily to release toxic elements or they may containments to their surfaces and remove harmful chemicals from the environment. However, nanoparticles are so small, we need special tools to observe and manipulate them. For example we use atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) in conjunction with other techniques to obtain nanoscale chemical, structural, and morphological data.
Transmission Electron Microscopy is used to image materials of a few to tens of nanometers in diameter, such as these hematite nanominerals.
The types of questions we address include:
How does the geochemical reactivity of Earth and environmental materials change in the nanoscale size range? Over what length scales does the size-dependence occur? We investigate the size dependence of nanomineral reactivity including metal sorption, surface-mediated redox reactions, photochemical reduction, formation, stability, and colloidal behavior.
How does aggregation influence nanoparticle reactivity? For nanoparticles, interparticle forces are stronger than gravitational settling. These interparticle forces lead to unique behaviors. We are exploring how particle size and shape influenes the associations of nanoparticles in solution, which dramatically influences their reactivity and potential for transport through natural waters and in porous media. We are studying the adsorption of arsenic to hematite aggregates as a probe of their internal structure. Additionally, we are working with Barry Bickmore's group at BYU and Boris Lau's group at Baylor University to understand the relationships between hematite nanoparticles aggregation and reactivity in solution. We hypothesize that size and morphology influence the formation of clusters in solution that restrict the accessibility of some dissolved ions but not others.
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Atomic Force Microscope image of hematite nanoparticle clusters deposited on a silica Quartz Crystal Microbalance substrate during a flow-through experiment. The field of view is approximately 20 microns. Cluster heights are approximately 100-150 nm. This work is a collaboration with Boris Lau's group at Baylor University.
What is the reactive surface area of nanoparticles? The surface area of mineral particles can be measured or defined in a variety of ways, including by gas adsorption (such as in the BET method) or geometric models. The surface area is a key parameter in many geochemical experiments and models. Which is the most appropriate surface area to use, and does “one size fit all” for every type of geochemical reaction? How accessible are spaces between aggregates to ions in solution, including potential contaminants? For example, in a collaborative study, our nanoscale characterization of goethite has shown that a different surface area is appropriate for phosphate and proton sorption due to the presence of nanoporosity not accessible to P. Also, we have demonstrated a 'cross-over' size delineating appropriate size ranges for geometric vs. BET surface areas for hematite nanoparticles.
WHAT HAPPENS TO RADIONUCLIDES WHEN BACTERIA FORM MINERAL NANOPARTICLES?
Where does uranim end up during magnetite formation by bacteria? (Madden, Swindle, Beazley, Moon, Phelps, Ravel)
The mineral magnetite is a common natural and industrial product of iron reduction, when Fe3+ in soils, sediments, corroding pipes, or other material is used as a bacterial electron acceptor. In-situ microbial metal reduction for the immobilization of toxic metals and radionuclides is an area of current research as a means of remediating contaminated ground water. The reduction of iron may result in the formation of magnetite when the activities of dissolved carbonate and sulfide are low and is often concurrent with the reduction of soluble uranyl ions to insoluble uraninite precipitates, removing the uranium from ground water. However, the fate of uranium co-reduced with iron during the production of magnetite remains a key knowledge gap and source of variability in previous studies. Distinct possibilities, including 1) incorporation of uranium into the magnetite crystal structure as U(VI) ions, 2) incorporation of U as U(IV) ions, 3) incorporation of U as uraninite domains, 4) external precipitation of separate uraninite and magnetite particles, all contribute uniquely to the fate and transport of uranium.
Transmission Electron Micrograph of a mixture of FeOOH laths/needles, a single crystal of magnetite formed by biological reduction (lower right), and a chain of biologically produced uraninite crystals ~ 50 nm across (image by Andrew Swindle).
Uranium-doped biogenic magnetite slurries were produced during fermentative reduction of ferric hydroxide precursor by cultures of Thermoanaerobacter strain TOR-39 at Oak Ridge National Laboratory in the Phelps group. Subsets of samples were analyzed by U L-3 edge EXAFS at the Advanced Photon Source at examined with powder X-ray diffraction and Transmission Electron Microscopy at OU. Our results indicate that over a long period of time (>2 years) under anaerobic conditions, distinct uraninite nanoparticles form that are originally extremely small (a few nanometers) but coarsen over time. These coarsened insoluble uraninite mineral nanoparticles should be relatively resistant to oxidation and remobilization of uranium in groundwater.
NANOPARTICLES THAT ARE OUT OF THIS WORLD!
Hematite nanoparticle aggregation as a low-temperature mechanism for forming coarse-grained hematite (with Megan Elwood Madden at OU and Vicky Hamilton at SWRI)
We have demonstrated that cryodessication of aqueous nanoparticle suspensions may be a likely formation pathway for coarse gray hematite on Mars by crystallographically oriented aggregation. This mechanism is consistent with both the widespread distribution of nanophase iron oxides on Mars the observed aqueous weathering mineral assemblages. In addition, aggregation of nanoparticles to form coarse-grained crystallites resolves conflicting observations of iron oxide grain sizes on Mars as determined by IR and Moessbauer spectroscopy.
Here’s how it works: as aqueous suspensions of hematite nanoparticles are frozen, crystallographic alignment of the individual 8-10 nm particles domains of <100 nm. These domains further aggregate into grains as large as millimeters in diameter. Using transmission and scanning electron microscopies, we were able to explore the various scales of this hierarchical assembly. Thermal infrared spectra of our cryodesiccated hematite material reproduce well spectra of coarse crystalline hematite collected from Mars. While the results are presented in the context of Mars, our findings include significant implications for the Earth. The results presented expand our understanding of the fate of nanoparticles in present-day environments. In addition, this new mechanism may influence interpretations of coarse hematite-bearing assemblages, including banded iron formations which record global shifts in oxidation states in the Archean and Proterozoic.
Thermal Emission IR spectra collected by Vicky Hamilton on specular hematite generated through nanoparticle aggregation (blue) shows the same 390 cm-1 feature as observed in coarse-grained hematite on Mars and a c-axis oriented hematite (Lane et al.).
Nanomineralogy of jarosite disolution products
(NASA - Elwood Madden, Madden, Rimstidt, Zahrai, and Miller)
Jarosite is an important metastable ferric sulfate in acid mine drainage systems, incorporating and later releasing heavy metals. Jarosite has also been observed in outcrops throughout Meridiani Planum by the MER Opportunity, leading to interpretations of widespread, though ephemeral, acidic fluids. Rates of jarosite dissolution have been measured under AMD and Mars-relevant conditions to determine the rate of iron and toxic metal release as well as constrain the lifetime of jarosite, and hence the maximum duration of water in jarosite-bearing sediments on Mars. TEM was used to analyze the texture and mineralogy of the reaction products. After several days at 273 K, the originally smooth jarosite spherules develop a surface texture of secondary precipitates indicative of incongruent dissolution with significant microporosity. Samples taken after a few hours of dissolution at 323K similarly show a vesicular texture where the outline of the original spherule is preserved and secondary precipitates have replaced much of the jarosite. Electron diffraction analysis suggests the reaction products at both temperature conditions are composed of nanocrystalline (1-50 nm) ferric hydroxide, hematite, and schwertmannite. The evolution of jarosite surface area during dissolution does not follow a simple relationship with time, and secondary precipitates contained within the original grain boundary likely will retain significant adsorbed or coprecipitated metals.
TEM image of jarosite dissoving with the development of significant intermal porosity and the formation of hematite nanoparticles in the surrounding solution. The scale bar is 50 nm.
Prospecting for nanodiamonds (NSF)
Lee Bement (Oklahoma Archaeological Survey) is the lead PI on this project, with Brian Carter (OSU), Alex Simms (OSU), and our group participating. We are investigating a controversial possible link between an extraterrestial impactor and climate/ cultural changes observed at many sites in the northern hemisphere approximately 13,000 years ago (the Younger Dryas). The controversy was recently featured on the PBS documentary "NOVA" (link). Nanodiamonds are known to form by various processes in outer space, such that their presence in specific sediment and soil horizons may be a signature of extraterrestrial impact (for example, recent Science and PNAS papers such as this one by Kennet et al.). We are exploring the presence of nanodiamonds in various Oklahoma soil/sediment horizons with well-controlled carbon dates and sedimentological contexts.
TEM image of nanodiamonds added to an Oklahoma soil recovered after extensive treatment and dissolution, validating our method for recovering possible extraterrestrial nanodiamonds. The inset electron diffraction pattern is an example of how we identify the crystallinte structure of the material in TEM images (cubic diamond, in this case).
EARTHQUAKES - ARE NANOPARTICLES AT "FAULT"?
We have been collaborating with Dr. Ze'ev Reches' group in our department to investigate the properties of nanoparticulate gouge produced during rock mechanics experiments simulating earthquake conditions. Barry Bickmore (BYU) led to charge to apply a new Atomic Force Microscope method to measure friction at the nanoscale. We (especially Ph.D. student Xiaofeng Chen) are applying this method to textures developed on various rock types during experiments. For example, abundant nanoparticles and nanoscale "slickensides" are produced (image below). The gouge greatly impacts the frictional response at the simulated faults, including a dramatic response to wetting and drying as the temperature increases. The properties of this nanoparticulate gouge may contribute to an explaination of the weakness of natural fault zones.
Atomic Force Microscopy image of nanoscale grooves (slickensides) a reflective grain of recrystallized gouge in a simulated earthquake experiment (Reches lab). The field of view is approximately 15 microns across. The grooves are only a few to tens of nanometers deep, while the associated nanopaticulate gouge can be seen adhering to the surface even after cleaning with compressed air.
Nanogeoscience education
Nano2Earth: Welcome to Nanoscience
We recently finished work with the national Center for the Environmental Implications of NanoTechnology to develop our curriculum, "Nano2Earth: Introducing nanotechnology through investigations of groundwater." for secondary school courses. A large team synthesized educational and research ideas to synthesize this interdisciplinary introduction to nanoscale science and technology. In the summer of 2011, Nano2Earth was published with the National Science Teachers Association Press (link).
Environmental / interfacial biogeochemistry
Reactions at the interfaces between minerals, water, and bacteria biogeochemistry often determine the distribution, reactivity, and fate of chemical elements. These interfacial biogeochemical processes lead to the redistribution of metals in soils, surface water, and groundwater. Relatively high concentrations of metals in water threaten the sustainability of our water supplies. These contaminants include natural forms resulting from higher concentrations of metals in regional source rocks, those associated with mining and industrial impacted waters, and those related to the nuclear power / weapons complex. In addition to the fundamental science of interfacial biogeochemistry, this research area include the coupling of biological processes and mineral surface processes to enhance the effectiveness of remediation.
Why are uranyl phosphate minerals associated with particular minerals in natural uranium deposits? Can increased understanding of the influence of mineral surfaces on uranyl-phosphate mineral precipitation inform new strategies for uranium remediation? (Munasinghe, Williams, and Madden) In-situ remediation of metals and radionuclides in the subsurface depends on the coupling of biogeochemical and microbiological processes. Fundamental science at the mineral-water-bacteria interface can guide strategies to sequester contaminants. We are currently investigating the role in mineral surface structure on the immobilization of uranium through phosphate addition.
Atomic Force Microscopy image of platy uranium phosphate precipitated with needles of goethite (FeOOH), a common soil and sediment mineral.
How can chromium be sequestered from groundwater by co-precipitation with iron oxides (Butler, Krumholz, Hansel, and Madden)? The hexavalent form of chromium is relatively mobile and toxic. On the other hand, the trivalent form is both an essential nutrient and less soluble in water. We will be investigating chemical and biological reactions that lead to the sequestration of chromium in mixed Cr-Fe minerals.
What are the geochemical hosts for arsenic in the Garber Sandstone (Miller, Westrop, Hu and Madden)? Through chemical extractions, X-ray diffraction, surface area analysis, and especially graphite furnace atomic absorption spectrophotometry, we are exploring the possibilty that amorphous silica serves as a reservior for arsenic in our local drinking water aquifer. Several wells drilled within the Oklahoma City and Norman areas have produced waters with arsenic in excess of EPA drinking water standards. We are collaborating with Dr. Max Hu (University of Texas, Arlington) also on this project.
How do solid Earth materials respond to dynamic biogeochemical conditions (Kendall and Madden)? Sediment cores from the USGS Norman Landfill research site have been characterized. At this site, dynamic interactions between a plume of leachate with the surrounding hydrogeological environment and microbial communities have generated an exciting field site. The USGS has identified various zones in the subsurface where anaerobic biogeochemical processes such as iron reduction, sulfate reduction, and methanogenesis are active. The clay mineral fraction of sediment cores was extracted and characterized by x-ray diffraction. The results show that x-ray diffraction cannot distinguish mineralogical differences between contaminated and uncontaminated cores even in the <2 micron fraction, despite the obvious phyical and chemical differences between the sample. We hypothesize that a majority of the solid response to the dynamic biogeochemical conditions occurs at the nanoscale, and we intend to compare background and contaminated sediments with transmission electron microscopy with nanoscale imaging, analysis, and diffraction capabilities.
How does substitution of arsenic into jarosite influence dissolution rates ? What are the relationships between reaction products and arsenic fate / transport (Kendall, Elwood Madden, and Madden)? Through chemical extractions, X-ray diffraction, surface area analysis, and especially graphite furnace atomic absorption spectrophotometry, we are exploring the possibilty that amorphous silica serves as a reservior for arsenic in our local drinking water aquifer. Several wells drilled within the Oklahoma City and Norman areas have produced waters with arsenic in excess of EPA drinking water standards.
Clay mineralogy
I manage and direct the powder X-ray diffraction lab, which is equipped for a variety of XRD analyses and sample preparation methods. We analyze rock cores from Devon Energy for bluk and clay mineralogy, and perform analyses on a myriad of samples for researchers across OU along with collaborators.
Can we demonstrate convincingly for the first time that magnetite may be produced during the smectite to illite transformation (Miller, Elmore, and Madden)? A growing body of paleomagnetic research suggests that chemical remagnitization often occurs coincident with the smectite to illite transition in sedimentary rocks undergoing diageneis. In this experimental study, we are investigating the mineralogical and geochemical constraints on the possibility of magnetite forming directly from iron in clay minerals.
What is the relationship between sediment clay mineralogy and extractable trichloroethylene contamination in a fractured aquifer (Miller, Imbrigotta, Lacombe, Wernette, Blumenthal, and Madden)? This work began with Matt Miller's summer internship with the USGS at the Naval Air Warfare Center in New Jersey. We demonstrated that in cyclically-bedded fractured sedimentary rocks of the Lockatong Formation, the residual concentration of TCE after extensive pump-and-treat remediation was related not to abundant smectite distribution, but rather to the presence of pore-filling clay-sized analcime and dolomite cements. Further work is investigating whether this relationship holds across multiple bedding cycles.
Other recent collaborations
Coupled biotic/abiotic reactivity and transformations of Mn oxides (Learman, CMU; Hansel, Harvard)
Stabilization of expansive soils with fly ash (Cerato and Elwood Madden, OU)
Transformations of calcium phosphate brushite in synthetic body fluids (Tas, OU Health Sciences Center)
Treatment of Ti implant materials with alkali solutions to increase biomineralization capacity (Tas, OU Health Sciences Center)
PUBLICATIONS
in preparation
Chen X, Madden AS, Bickmore BR, and Reches ZR (in preparation) Nano-micro- scale rock friction, to be submitted to Nature Geoscience.
Kendall MR, Madden AS, Elwood Madden ME, Hu Q (in preparation) Rates and products of arsenojarosite dissolution¸ Geochimica et Cosmochimica Acta.
Lau B, Huang R, and Madden AS (in preparation) Electrostatic adsorption of hematite nanoparticles on self-assembled monolayer surfaces, Journal of Nanoparticle Research.
Madden AS, Munasinghe PS, Kendall MR, Elwood Madden ME, Brooks SC, Williams J (in preparation) Dynamic uranyl phosphate sorption and precipitation, Applied Geochemistry.
Miller MA, Madden AS, Elmore RD (in preparation) Laboratory synthesis of iron-rich 10Å clays from nontronite: implications for magnetite authigenesis, Clays and Clay Minerals.
Miller MA, Madden AS, HU Q, Westrop JP (in preparation) Silica as a reservoir for arsenic in quartz-rich sediments, Chemical Geology.
Moon J-W, Duty CE, Love LJ, Ivanov IN, Rawn CJ, Rondinone AJ, Lauf RJ, Li Y-L, Madden AS, Mosher JJ, Everett S, Phelps TJ (in preparation) Production of microbially‐mediated CdS quantum dots, Journal of Microbial Methods.
Zahrai S, Elwood Madden ME, Madden AS, Rimstidt JD, Miller MA (in preparation) Dissolution rates and particle lifetimes of Na-Jarosite under Mars-relevant conditions. To be submitted to Icarus
submitted
Kim C, Kendall MR, Miller MA, Long CL, Larson PR, Humphrey MB, Madden AS, Tas AC (submitted) Comparison of titanium soaked in 5M NaOH or 5M KOH solutions, Journal of Biomedical Materials Research.
Lin B, Cerato AB, Madden AS, and Elwood Madden ME (submitted) Microscopic Analysis of the Effect of Fly Ash on the Hydromechanical Alterations of Two Expansive Soils from Oklahoma. Journal of Materials in Civil Engineering.
Madden AS, Swindle AL, Beazley MJ, Moon J-W, Ravel B, Phelps TJ (submitted) Long-term solid-phase Fate of iron and uranium during biological magnetite formation, American Mineralogist.
Sweet AC, Soreghan GS, Sweet DE, Soreghan MJ, Madden AS (submitted) Sedimentological, Geochemical and Provenance Data from Middle Permian Redbeds (Oklahoma): Implications for Palaeoclimate and Atmospheric Circulation in Western Pangaea, Sedimentology.
in press / published
Elwood Madden ME, Madden AS, Rimstidt JD, Zahrai S, Kendall MR, and Miller MA (in press) Jarosite dissolution rates and nanoscale mineralogy, Geoshimica et Cosmochimica Acta.
Miller MA, Kendall MR, Jain MK, Larson PR, Madden AS, and Tas AC (in press) Testing of brushite (CaHPO4·2H2O) in synthetic biomineralization solutions and in situ crystallization of brushite micro-granules, Journal of the American Ceramic Society.
Hochella MF, Aruguete D, Kim B, Madden AS (2011) Naturally occurring inorganic nanoparticles: General assessment and a global budget for one of Earth's last unexplored major geochemical components. Nature's Nanostructures, Guo B and Barnard A (eds.), Pan Stanford Publishing Pte Ltd.
Learman DR, Wankel SD, Webb, SM, Martinez N, Madden AS, Hansel CM (2011) Coupled biotic-abiotic reaction pathway mediates the formation and structural evolution of biogenic Mn oxides, Geochimica et Cosmochimica Acta, 75: 6048-6063.
Madden AS, Hochella MF, Jr., Glasson GE, Grady JR, Bank TL, Green AM, Norris MA, Hurst AN, and Eriksson SC (2011) Welcome to Nanoscience: Interdisciplinary Environmental Explorations, Grades 9–12. National Science Teachers Association Press, ISBN 978-1-93613-732-9.
Ekstrom EB, Learman DR, Madden AS, Hansel CM (2010) Contrasting Effects of Al Substitution on Microbial Reduction of Fe(III) Oxides, Geochimica et Cosmochimica Acta 74, 7086-7099
Kosoglu L, Bickmore BR, Filz G, Madden AS (2010) Atomic Force Microscopy Method for Measuring Smectite Coefficients of Friction, Clays and Clay Minerals, 58(6):813-820.
Madden AS, Elwood Madden MEE, Hamilton VE, Larson PR, Miller MA (2010) Low-temperature mechanism for formation of crystallographically aligned specular hematite, Earth and Planetary Science Letters 298, 377-384.
Vishnivetskaya TA, Brandt CC, Madden AS, Drake MS, Kostka JE, Akob DM, Kuesel K, Palumbo AV (2010) Microbial Community Changes in Response to Ethanol or Methanol Amendments for U(VI) Reduction, Applied and Environmental Microbiology 76(17):5728-5735.
Elwood Madden ME, Madden AS, Rimstidt JD (2009) How long was Meridiani Planum wet? Applying a jarosite stopwatch to constrain the duration of diagenesis, Geology 37(7) 635-638. Link
Grady JR and Madden AS (2009) Integrating the sciences to investigate groundwater pollution, Science Activities 46(4) 7-14.
Bose S, Lower BH, Gorby YA, Kennedy DW, McCrady DE, Madden AS, Hochella MF Jr., (2009) Bioreduction of hematite nanoparticles by the dissimilatory iron reducing bacterium Shewanella oneidensis MR-1, Geochimica et Cosmochimica Acta. Link
Madden AS, Palumbo AV, Ravel B, Vishnivetskaya TA,Phelps TJ, Schadt CS, Brandt CC, (2009) Donor-dependent extent of uranium reduction for bioremediation of contaminated sediment microcosms, Journal of Environmental Quality. Link
Bank TL, Kukkadapu RK, Madden
AS, Ginder-Vogel MA, Baldwin ME, Jardine PM (2008) Effects of
sterilization on the physico-chemical properties of natural sediments from the
oak ridge reservation, Chemical
Geology 251:1-7. Link
Chernyshova IV, Hochella MF, Madden AS (2007) Size-dependent structural transformations of hematite nanoparticles. 1. Phase transition, Physical Chemistry Chemical Physics 9, 1736-1750. Link
Madden AS, Knefel AC, Grady JR, Glasson GE, Hochella MF, Jr., Eriksson SC, Bank TL, Cecil K, Green A, Hurst D, Norris M, Schreiber ME (2007) Nano2Earth: Incorporating cutting-edge research into secondary education through scientist-educator partnerships, Journal of Geoscience Education 55(5), 402-412. Link
Madden AS, Smith AC, Balkwill DL, Fagan LA, Phelps TJ (2007) Microbial uranium immobilization independent of nitrate reduction, Environmental Microbiology 9(9), 2321–2330. Link
Velbel MA, McGuire JT, and Madden AS (2007) Scanning electron microscopy of garnet from southern Michigan soils: Etching rates and inheritance of pre-glacial and pre-pedogenic grain-surface textures, Developments in Sedimentology, 58, 413-432. Link
Madden AS, Hochella MF, Jr., and Luxton TD (2006) Insights for size-dependent reactivity of hematite nanomineral surfaces through Cu2+ sorption, Geochimica et Cosmochimica Acta 70(16) 4095-4014. Link
Foresti E, Hochella MF, Jr., Lesci IG, Madden AS, Roveri N, and Xu H (2005) Morphological and chemical-physical characterization of Fe doped synthetic chrysotile nano-crystals, Advanced Functional Materials 15(6): 1009-1016. Link
Hochella MF, Jr., and Madden, AS (2005) Earth’s nano-compartment for toxic metals, Elements 1(4) 199-203. Download
Madden AS, and Hochella MF, Jr. (2005) A test of geochemical
reactivity as a function of mineral size: Manganese oxidation promoted by
hematite nanoparticles, Geochimica
et Cosmochimica Acta 69(2) 389-398. Link
COURSES
| Spring 2012 | GEOL 1114 Physical Geology for Scientists and Engineers GEOL 3154 Environmental Geology |
| Fall 2011 | GEOL 5544 Minerals and the Environment |
| Spring 2011 | GEOL 3154 Environmental Geology (with lab) GEOL 6970 Clay Mineralogy |
| Spring 2010
|
GEOL 1114 Physical Geology for Scientists and Engineers |
| Fall 2009 | GEOL 5544 Minerals and the Environment |
RECENT PRESENTATIONS
Ikuma K, Madden AS, Lonergan MC, Lau BLT (2012) The role of extracellular polymeric substances in nanoparticle-biofilm interactions, Goldschmidt 2012.
Kendall MR, Madden AS, Elwood Madden ME, Hu Q (2012) Influence of arsenic incorporation on jarosite dissolution rates and reaction products, Goldschmidt 2012.
Learman DR, Voelker B, Madden AS, Hansel CM (2012) Manganese oxides from abiotic oxidation of Mn(II) by superoxide radical, American Chemical Society spring 2012 meeting.
Madden AS, Elwood Madden ME, Rimstidt JD, Kendall MR (2012) Time-Course Mineralogy and Texture of Nanoscale Jarosite Dissolution Products, Lunar and Planetary Science Conference.
Madden AS, Swindle AL, Bement LC, Carter BJ, Simms AR, Menamara B (2012) Nanodiamonds and carbonaceous grains in Bull Creek Valley, Oklahoma, Goldschmidt 2012.
Miller MA, Dulin SA, Madden AS, Elmore RD (2012) Magnetic properties of source clays: rock magnetic implications, Goldschmidt 2012.
Moon J-W, Ivanov IN, Duty CE, Love LJ, Wang W, Rawn CJ, Li Y-L, Madden AS, Mosher JJ, Suresh AK, Rondinone AJ, Rawn CJ, Lauf RJ, Phelps TJ (2012) Bacterially Precipitated Nanoparticulate Cadmium Sulfide Quantum Dot Production, American Society for Microbiology.
Pritchett BN, Elwood Madden ME, Madden AS (2012) Salinity and temperature effects on the dissolution of natrojarosite and K-jarosite, Lunar and Planetary Science Conference.
Swindle AL, Madden AS (2012) Fate of magnetite nanoparticles in leachate-impacted groundwater, Goldschmidt 2012.
Zahrai SK, Elwood Madden ME, Madden AS, Rimstidt JD (2012) Comparing Na-jarosite and K-jarosite dissolution rates to determine the effects of crystal chemistry on jarosite lifetimes, Lunar and Planetary Science Conference.
Bement LC, Cater BJ, Simms A, Swindle A, and Madden AS (2011) The Bull Creek valley stream terraces, buried soils, and paleo-environment in the Oklahoma panhandle, USA. International Union for Quaternary Research 2011 Congress, Bern, Switzerland.
Chen X, Madden AS, Bickmore BR, Reches Z (2011) Rock Friction at the Micro-scale. American Geophysical Union national meeting, San Francisco, CA.
Elwood Madden ME, Madden AS, Pritchett B, Kendall MR, Zahrai S, Rimstidt JD, Hamilton VE (2011) From rover to laboratory: examining jarosite dissolution and coupled hematite precipitation to constrain ancient aqueous environments and Meridiani Planum, Geological Society of America Annual Meeting, Minneapolis, MN.
Hochella MF, Aruguete D, Kim B, Madden AS (2011) Naturally occurring inorganic nanoparticles: General assessment and a global budget for one of Earth's last unexplored major geochemical components¸ Goldschmidt Conference, Prague, Czech Republic.
Kendall MR, Madden AS, Elwood Madden ME (2011) Rates and products of arsenojarosite dissolution, Geological Society of America Annual Meeting, Minneapolis, MN.
Madden AS, Munasinghe PS, Kendall MR, and Elwood Madden ME (2011) Dynamic uranyl phosphate adsorption and precipitation. American Chemical Society 241st Annual Meeting, Anaheim, CA.
Miller MA, Madden AS, Lacombe PJ, Imbrigotta TE, Goode DJ, Kendall MR, Blumenthal JS, Wernette SJ (2011) Clay mineralogy of Van Houten cycles in the Lakatong Formation, Newark Basin, Trenton, NJ. Clay Minerals Society Annual Meeting, Stateline, NV (3rd place winner).
Pritchett B, Elwood Madden ME, Madden AS (2011) Effects of activity of water on the dissolution rate of K-jarosite, Geological Society of America Annual Meeting, Minneapolis, MN.
Bickmore BR, Rosso KM, Madden AS (2010) Surface Structure Effects on Gibbsite Nanoparticle Reactivity, Goldschmidt Conference, Knoxville TN.
Elwood Madden, M.E., Madden, A.S., Hamilton, V. E., Rimstidt, J.D., Zahrai, S. K., Miller, M.A. (2010) Diagenesis of jarosite and hematite: a low temperature path to nanophase iron oxides and “specular” c-axis alligned hematite on Mars. Geochim. Cosmochim. Acta Goldschmidt Conference Abstract.
Lau B, Huang R, and Madden AS (2010) Adsorption of hematite nanoparticles on self-assembled monolayer modified surfaces, Environmental Effects of Nanoparticles and Nanomaterials: 2010, Clemson SC.
Madden AS, Elwood Madden ME, Hamilton VE (2010) Formation of Mars analog crystalline hematite from nanophase hematite under low temperature aqueous conditions. Lunar and Planetary Science Conference.
Madden AS, Bickmore BR, Tadanier CJ, Lau BLT, Miller MA, Huang R (2010) Irreversible reductions in surface area of nanoparticles depends on drying conditions Goldschmidt Conference, Knoxville TN.
Swindle AL, Madden AS, Beazley MJ, Moon J-W, Ravel B, Phelps TJ (2010) Fate of Ferric-Hydroxide Associated U(VI) during Biological Magnetite Formation, Goldschmidt Conference, Knoxville TN.
Zahrai SK, Elwood Madden ME, Madden AS, Miller M, Rimstidt JD (2010) Jarosite dissolution rates and lifetimes under Mars-analog conditions. Lunar and Planetary Science Conference.