Staff information

PNNL Publications

2024

• Liu W., Z. Wang, M.E. Bowden, O. Qafoku, and K.M. Rosso. 2024. "Vivianite oxidation is not photocatalyzed." Geochimica et Cosmochimica Acta 373, no. 2024:109-121. PNNL-SA-186116. doi:10.1016/j.gca.2024.03.031
• Sassi M., O. Qafoku, M.E. Bowden, C.I. Pearce, D. Latta, Q. Miller, and M.D. Boamah, et al. 2024. "Influence of Time and Ageing Conditions on the Properties of Ferrihydrite." Environmental Science Nano 11, no. 4:1682-1692. PNNL-SA-192693. doi:10.1039/D3EN00828B

2023

• Bowman M.M., A.E. Heath, T. Varga, A. Battu, R.K. Chu, J.G. Toyoda, and T. Cheeke, et al. 2023. "One thousand soils for molecular understanding of belowground carbon cycling." Frontiers in Soil Science 3. PNNL-SA-183617. doi:10.3389/fsoil.2023.1120425
• Engel M., V. Noel, S. Pierce, L. Kovarik, R.K. Kukkadapu, J.S. Lezama Pacheco, and O. Qafoku, et al. 2023. "Structure and composition of natural ferrihydrite nano-colloids in anoxic groundwater." Water Research 238. PNNL-SA-181172. doi:10.1016/j.watres.2023.119990
• Mergelsberg S.T., B.P. Rajan, B.A. Legg, L. Kovarik, S.D. Burton, G.M. Bowers, and M.E. Bowden, et al. 2023. "Nanoscale Mg-Depleted Layers Slow Carbonation of Forsterite (Mg2SiO4) When Water Is Limited." Environmental Science & Technology Letters 10, no. 1:98-104. PNNL-SA-178504. doi:10.1021/acs.estlett.2c00866
• Saslow S.A., E. Cordova, N.M. Escobedo Avalos, O. Qafoku, M.E. Bowden, C.T. Resch, and N. Lahiri, et al. 2023. "Accumulation mechanisms for contaminants on weak-base hybrid ion exchange resins." Journal of Hazardous Materials 459. PNNL-SA-167020. doi:10.1016/j.jhazmat.2023.132165
• Zambare N.M., B.W. Arey, O. Qafoku, K. Koirala, L. Kovarik, and A. Dohnalkova. 2023. "Novel Focused Ion Beam Liftouts for Spatial Characterization of Spherical Biominerals With Transmission Electron Microscopy." Microscopy and Microanalysis 29, no. 4:1467-1773. PNNL-SA-177391. doi:10.1093/micmic/ozad031
• Zhao Q., O. Qafoku, and K.A. Rod. 2023. Investigating carbon stabilization in soils via mineral adsorption: What are we missing when we define mineral associated organic matter. PNNL-35030. Richland, WA: Pacific Northwest National Laboratory. Investigating carbon stabilization in soils via mineral adsorption: What are we missing when we define mineral associated organic matter.

2022

• Bhattacharjee A., O. Qafoku, J. Richardson, L.N. Anderson, K.C. Schwarz, L.M. Bramer, and G.X. Lomas, et al. 2022. "A Mineral-Doped Micromodel Platform Demonstrates Fungal Bridging of Carbon Hot Spots and Hyphal Transport of Mineral-Derived Nutrients." mSystems 7, no. 6:Art. No. e00913-22. PNNL-SA-167557. doi:10.1128/msystems.00913-22
• Liu J., S.D. Taylor, O. Qafoku, B.W. Arey, R.J. Colby, A.M. Eaton, and J. Bartrand, et al. 2022. "Visualizing the distribution of water in nominally anhydrous minerals at the atomic scale: Insights from atom probe tomography on fayalite." Geophysical Research Letters 49, no. 2:Art. No. e2021GL094914. PNNL-SA-160964. doi:10.1029/2021GL094914
• Lybrand R.A., O. Qafoku, M.E. Bowden, M.F. Hochella, L. Kovarik, D.E. Perea, and N. Qafoku, et al. 2022. "Fungal hyphae develop where titanomagnetite inclusions reach the surface of basalt grains." Scientific Reports 12. PNNL-SA-163525. doi:10.1038/s41598-021-04157-z
• Rooney E.C., V.L. Bailey, K.F. Patel, M.I. Dragila, M.I. Dragila, A. Battu, and A.C. Buchko, et al. 2022. "Soil pore network response to freeze-thaw cycles in permafrost aggregates." Geoderma 411. PNNL-SA-165886. doi:10.1016/j.geoderma.2021.115674
• Schindler M., M.J. Schreckenbach, M.G. Wirth, O. Qafoku, L. Kovarik, and D.E. Perea. 2022. "Deciphering the Distribution and Crystal-Chemical Environment of Arsenic, Lead, Silica, Phosphorous, Tin and Zinc in a Porous Ferrihydrite Grain using Transmission Electron Microscopy and Atom Probe Tomography." ACS Earth and Space Chemistry 6, no. 3:558-570. PNNL-SA-168344. doi:10.1021/acsearthspacechem.1c00374
• Yu Y., H.Y. Sintim, A.F. Astner, D.G. Hayes, A.I. Bary, A. Zelenyuk-Imre, and O. Qafoku, et al. 2022. "Enhanced Transport of TiO2 in Unsaturated Sand and Soil after Release from Biodegradable Plastic during Composting." Environmental Science & Technology 56, no. 4:2398-2406. PNNL-SA-167956. doi:10.1021/acs.est.1c07169

2021

• Dong Z., G. Deblonde, A. Middleton, D. Hu, A. Dohnalkova, L. Kovarik, and O. Qafoku, et al. 2021. "Microbe-Encapsulated Silica Gel Biosorbents for Selective Extraction of Scandium from Coal Byproducts." Environmental Science & Technology 55, no. 9:6320-6328. PNNL-SA-161032. doi:10.1021/acs.est.0c08632
• Lawter A.R., T.G. Levitskaia, O. Qafoku, M.E. Bowden, F. Cintron Colon, and N. Qafoku. 2021. "Simultaneous immobilization of aqueous co-contaminants using a bismuth layered material." Journal of Environmental Radioactivity 237. PNNL-SA-147691. doi:10.1016/j.jenvrad.2021.106711
• Loring J.S., O. Qafoku, C.J. Thompson, A.S. Mcneill, M. Vasiliu, D.A. Dixon, and Q. Miller, et al. 2021. "Synergistic Coupling of CO2 and H2O during Expansion of Clays in Supercritical CO2-CH4 Fluid Mixtures." Environmental Science & Technology 55, no. 16:11192-11203. PNNL-SA-143713. doi:10.1021/acs.est.1c00275
• Lybrand R.A., D. Veghte, S. China, D. Zaharescu, C.R. Anderton, R. Aleman, and P. Schroeder, et al. 2021. "Deciphering the incipient phases of ice-mineral interactions as a precursor of physical weathering." ACS Earth and Space Chemistry 5, no. 5:1233-1241. PNNL-SA-157793. doi:10.1021/acsearthspacechem.0c00345
• O'Callahan B.T., O. Qafoku, V. Balema, O. Negrette, A. Passian, M.H. Engelhard, and K.M. Waters. 2021. "Atomic force microscopy and infrared nanospectroscopy of COVID-19 spike protein for quantification of adhesion to common surfaces." Langmuir 37, no. 41:12089-12097. PNNL-SA-164328. doi:10.1021/acs.langmuir.1c01910
• Qafoku O., B.T. O'Callahan, Q. Zhao, M.E. Bowden, R.K. Kukkadapu, J.S. Loring, and A. Andersen. 2021. "Characterizing the Localization of Organic C on Mineral Surfaces: A Correlative Microscopy/spectroscopy Approach." Microscopy and Microanalysis 27, no. S1:306-307. PNNL-SA-165849. doi:10.1017/S1431927621001665

2020

• Cordova E., V.A. Garayburu-Caruso, C.I. Pearce, K.J. Cantrell, J.W. Morad, E.C. Gillispie, and B.J. Riley, et al. 2020. "Hybrid Sorbents for 129I Capture from Contaminated Groundwater." ACS Applied Materials & Interfaces 12, no. 23:26113-26126. PNNL-SA-147889. doi:10.1021/acsami.0c01527
• Dembowski M., M. Snyder, C.H. Delegard, J.G. Reynolds, T.R. Graham, H. Wang, and I.I. Leavy, et al. 2020. "Ion-ion interactions enhance aluminum solubility in alkaline suspensions of nano-gibbsite (a-Al(OH)3) with sodium nitrite/nitrate." Physical Chemistry Chemical Physics 22, no. 8:4368-4378. PNNL-SA-142835. doi:10.1039/C9CP05856G
• Mergelsberg S.T., S.N. Kerisit, E.S. Ilton, O. Qafoku, C.J. Thompson, and J.S. Loring. 2020. "Low Temperature and Limited Water Activity Reveal a Pathway to Magnesite via Amorphous Magnesium Carbonate." Chemical Communications 56, no. 81:12154-12157. PNNL-SA-154304. doi:10.1039/D0CC04907G
• Pearce C.I., E. Cordova, W.L. Garcia, S.A. Saslow, K.J. Cantrell, J.W. Morad, and O. Qafoku, et al. 2020. "Evaluation of materials for iodine and technetium immobilization through sorption and redox-driven processes." Science of the Total Environment 716. PNNL-SA-138462. doi:10.1016/j.scitotenv.2019.136167
• Placencia-Gomez R.E., S.N. Kerisit, H.S. Mehta, O. Qafoku, C.J. Thompson, T.R. Graham, and E.S. Ilton, et al. 2020. "Critical Water Coverage during Forsterite Carbonation in Thin Water Films: Activating Dissolution and Mass Transport." Environmental Science & Technology 54, no. 11:6888-6899. PNNL-SA-151291. doi:10.1021/acs.est.0c00897
• Qafoku O., L. Kovarik, M.E. Bowden, E. Nakouzi, A. Sheng, J. Liu, and C.I. Pearce, et al. 2020. "Nanoscale Observations of Fe(II)-Induced Ferrihydrite Transformation." Environmental Science Nano 7, no. 10:2953-2967. PNNL-SA-155340. doi:10.1039/D0EN00730G
• Rod K.A., K.F. Patel, S. Kumar, E. Cantando, W. Leng, R.K. Kukkadapu, and O. Qafoku, et al. 2020. "Dispersible Colloid Facilitated Release of Organic Carbon From Two Contrasting Riparian Sediments." Frontiers in Water 2. PNNL-SA-160357. doi:10.3389/frwa.2020.560707
• Rod K.A., P. Smith, W. Leng, S.M. Colby, R.K. Kukkadapu, M.E. Bowden, and O. Qafoku, et al. 2020. "Water-dispersible nanocolloids and higher temperatures promote the release of carbon from riparian soil." Vadose Zone Journal 19, no. 1:Article No. e20077. PNNL-SA-156976. doi:10.1002/vzj2.20077
• Sassi M., E.D. Walter, O. Qafoku, K.M. Rosso, and Z. Wang. 2020. "Radiation-induced interfacial hydroxyl transformation on boehmite and gibbsite basal surfaces." Journal of Physical Chemistry C 124, no. 40:22185-22191. PNNL-SA-153541. doi:10.1021/acs.jpcc.0c06844

2019

• Bylaska E.J., J.G. Catalano, S.T. Mergelsberg, S.A. Saslow, O. Qafoku, M.P. Prange, and E.S. Ilton. 2019. "Association of Defects and Zinc in Hematite." Environmental Science & Technology 53, no. 23:13687-13694. PNNL-SA-144849. doi:10.1021/acs.est.9b04323
• Huang X., Y. Chen, E.D. Walter, M. Zong, Y. Wang, X. Zhang, and O. Qafoku, et al. 2019. "Facet-Specific Photocatalytic Degradation of Organics by Heterogeneous Fenton Chemistry on Hematite Nanoparticles." Environmental Science & Technology 53, no. 17:10197-10207. PNNL-SA-146189. doi:10.1021/acs.est.9b02946
• Lybrand R.A., J.C. Austin, J. Fedenko, R.E. Gallery, E.C. Rooney, P. Schroeder, and D.G. Zaharescu, et al. 2019. "A coupled microscopy approach to assess the nano-landscape of weathering." Scientific Reports 9, no. 1:Article Number 5377. PNNL-SA-142858. doi:10.1038/s41598-019-41357-0
• Miller Q., D.A. Dixon, S.D. Burton, E.D. Walter, D.W. Hoyt, A.S. Mcneill, and J. Moon, et al. 2019. "Surface-Catalyzed Oxygen Exchange during Mineral Carbonation in Nanoscale Water Films." Journal of Physical Chemistry C 123, no. 20:12871-12885. PNNL-SA-141756. doi:10.1021/acs.jpcc.9b02215
• Soltis J.A., M.E. McBriarty, O. Qafoku, S.N. Kerisit, E. Nakouzi, J.J. De Yoreo, and E.S. Ilton. 2019. "Can Mineral Growth by Oriented Attachment Lead to Incorporation of Uranium(VI) into the Structure of Goethite?." Environmental Science Nano 6, no. 10:3000-3009. PNNL-SA-145133. doi:10.1039/c9en00779b
• Wood C.E., O. Qafoku, J.S. Loring, and A.M. Chaka. 2019. "Role of Fe(II) Content in Olivine Carbonation in Wet Supercritical CO2." Environmental Science & Technology Letters 6, no. 10:592-599. PNNL-SA-146347. doi:10.1021/acs.estlett.9b00496

2018

• Lawter A.R., N. Qafoku, R.M. Asmussen, R.K. Kukkadapu, O. Qafoku, D.H. Bacon, and C.F. Brown. 2018. "Element mobilization and immobilization from carbonate rocks between CO2 storage reservoirs and the overlying aquifers during a potential CO2 leakage." Chemosphere 197. PNNL-SA-125304. doi:10.1016/j.chemosphere.2017.12.199
• Lawter A.R., W.L. Garcia, R.K. Kukkadapu, O. Qafoku, M.E. Bowden, S.A. Saslow, and N. Qafoku. 2018. "Technetium and iodine aqueous species immobilization and transformations in the presence of strong reductants and calcite-forming solutions: Remedial action implications." Science of the Total Environment 636. PNNL-SA-129751. doi:10.1016/j.scitotenv.2018.04.240
• Miller Q., E.S. Ilton, O. Qafoku, D.A. Dixon, M. Vasiliu, C.J. Thompson, and H.T. Schaef, et al. 2018. "Water Structure Controls Carbonic Acid Formation in Adsorbed Water Films." The Journal of Physical Chemistry Letters 9, no. 17:4988-4994. PNNL-SA-136469. doi:10.1021/acs.jpclett.8b02162
• Pearce C.I., R.J. Serne, S.A. Saslow, W. Um, R.M. Asmussen, M.D. Miller, and O. Qafoku, et al. 2018. "Characterizing Technetium in Subsurface Sediments for Contaminant Remediation." ACS Earth and Space Chemistry 2, no. 11:1145-1160. PNNL-SA-130781. doi:10.1021/acsearthspacechem.8b00077
• Pearce C.I., S.A. Saslow, R.M. Asmussen, W. Um, J.N. Serne, M.D. Miller, and O. Qafoku, et al. 2018. "Exploiting Knowledge of Technetium in the Subsurface to Develop Remediation Strategies - 18223." In Proceedings of the 44th Annual Waste Management Conference (WM2018), Nuclear and Industrial Robotics, Remote Systems and Other Emerging Technology, March 18-22, 2018, Phoenix, AZ, 8, 5082-5090. Tempe, Arizona:Waste Management Symposia, Inc. PNNL-SA-130601.
• Plymale A.E., J.R. Wells, E.B. Graham, O. Qafoku, S.M. Brooks, and B.D. Lee. 2018. "Bacterial productivity in a ferrocyanide-contaminated aquifer at a nuclear waste site." Water 10, no. 8:Article No. 1072. PNNL-SA-135770. doi:10.3390/w10081072
• Popel A., T.W. Wietsma, M.H. Engelhard, A. Lea, O. Qafoku, C. Grygiel, and I. Monnet, et al. 2018. "The Effect of Ion Irradiation on the Dissolution of UO2 and UO2-based Simulant Fuel." Journal of Alloys and Compounds 735. PNNL-SA-129551. doi:10.1016/j.jallcom.2017.11.216
• Qafoku O., E.S. Ilton, M.E. Bowden, L. Kovarik, X. Zhang, R.K. Kukkadapu, and M.H. Engelhard, et al. 2018. "Synthesis of Nanometer-Sized Fayalite and Magnesium-Iron(II) Mixture Olivines." Journal of Colloid and Interface Science 515. PNNL-SA-131663. doi:10.1016/j.jcis.2018.01.036

2017

• McBriarty M.E., J.A. Soltis, S.N. Kerisit, O. Qafoku, M.E. Bowden, E.J. Bylaska, and J.J. De Yoreo, et al. 2017. "Trace Uranium Partitioning in a Multi-Phase Nano-FeOOH System." Environmental Science & Technology 51, no. 9:4970-4977. PNNL-SA-123284. doi:10.1021/acs.est.7b00432
• McGrail B.P., H.T. Schaef, F.A. Spane, J.A. Horner, A.T. Owen, J.B. Cliff, and O. Qafoku, et al. 2017. "Wallula Basalt Pilot Demonstration Project: Post-Injection Results and Conclusions." Energy Procedia 114. PNNL-SA-121381. doi:10.1016/j.egypro.2017.03.1716
• McGrail B.P., H.T. Schaef, F.A. Spane, J.B. Cliff, O. Qafoku, J.A. Horner, and C.J. Thompson, et al. 2017. "Field Validation of Supercritical CO2 Reactivity with Basalts." Environmental Science & Technology Letters 4, no. 1:6-10. PNNL-SA-119127. doi:10.1021/acs.estlett.6b00387
• Qafoku O., C.I. Pearce, A. Neumann, L. Kovarik, M. Zhu, E.S. Ilton, and M.E. Bowden, et al. 2017. "Tc(VII) and Cr(VI) Interaction with a Naturally Reduced Ferruginous Smectite from the Redox Transition Zone." Environmental Science & Technology 51, no. 16:9042-9052. PNNL-SA-127378. doi:10.1021/acs.est.7b02191
• Xu M., S.L. Riechers, E.S. Ilton, Y. Du, L. Kovarik, T. Varga, and B.W. Arey, et al. 2017. "Manganese-Calcium Intermixing Facilitates Heteroepitaxial Growth at the (10-14) Calcite-Water Interface." Chemical Geology 470. PNNL-SA-125533. doi:10.1016/j.chemgeo.2017.09.001

2016

• Byrne J., G. van der Laan, A. Figueroa, O. Qafoku, C. Wang, C.I. Pearce, and M.J. Jackson, et al. 2016. "Size dependent microbial oxidation and reduction of magnetite nano-and micro-particles." Scientific Reports 6. PNNL-SA-119852. doi:10.1038/srep30969
• Chaka A.M., A.R. Felmy, and O. Qafoku. 2016. "Ab initio thermodynamics of magnesium carbonates and hydrates in water-saturated supercritical CO2 and CO2-rich regions." Chemical Geology 434. PNNL-SA-117665. doi:10.1016/j.chemgeo.2016.04.005
• Hu M.Y., X. Deng, S. Thanthiriwatte, V.E. Jackson, C. Wan, O. Qafoku, and D.A. Dixon, et al. 2016. "In Situ Natural Abundance 17O and 25Mg NMR Investigation of Aqueous Mg(OH)2 Dissolution in the Presence of Supercritical CO2." Environmental Science & Technology 50, no. 22:12373-12384. PNNL-SA-118648. doi:10.1021/acs.est.6b03443

2015

• Felmy A.R., O. Qafoku, B.W. Arey, L. Kovarik, J. Liu, D.E. Perea, and E.S. Ilton. 2015. "Enhancing Magnesite Formation at Low Temperature and High CO2 Pressure: The Impact of Seed Crystals and Minor Components." Chemical Geology 395. PNNL-SA-107559. doi:10.1016/j.chemgeo.2014.12.003
• Gilson E.R., S. Huang, P.G. Koster van Groos, K.G. Scheckel, O. Qafoku, A.D. Peacock, and D.I. Kaplan, et al. 2015. "Uranium redistribution due to water table fluctuations in sandy wetland mesocosms." Environmental Science & Technology 49, no. 20:12214-12222. PNNL-SA-112492. doi:10.1021/acs.est.5b02957
• Loring J.S., J. Chen, P. Benezeth Ep Gisquet, O. Qafoku, E.S. Ilton, N.M. Washton, and C.J. Thompson, et al. 2015. "Evidence for Carbonate Surface Complexation during Forsterite Carbonation in Wet Supercritical Carbon Dioxide." Langmuir 31, no. 27:7533-7543. PNNL-SA-110896. doi:10.1021/acs.langmuir.5b01052
• Loring J.S., J. Chen, P. Benezeth, O. Qafoku, E.S. Ilton, N.M. Washton, and C.J. Thompson, et al. 2015. "Evidence for Carbonate Surface Complexation during Forsterite Carbonation in Wet Supercritical Carbon Dioxide." Langmuir 31, no. 27:7533-7543. PNNL-SA-109630. doi:10.1021/acs.langmuir.5b01052
• Qafoku O., D.A. Dixon, K.M. Rosso, H.T. Schaef, M.E. Bowden, B.W. Arey, and A.R. Felmy. 2015. "Dynamics of Magnesite Formation at Low-Temperature and High pCO2 in Aqueous Solution." Environmental Science & Technology 49, no. 17:10736-10744. PNNL-SA-105262. doi:10.1021/acs.est.5b02588
• Xu M., E.S. Ilton, M.H. Engelhard, O. Qafoku, A.R. Felmy, K.M. Rosso, and S.N. Kerisit. 2015. "Heterogeneous growth of cadmium and cobalt carbonate phases at the (101¯4) calcite surface." Chemical Geology 397. PNNL-SA-104045. doi:10.1016/j.chemgeo.2015.01.003

2014

• Pearce C.I., J. Liu, D.R. Baer, O. Qafoku, S.M. Heald, E. Arenholz, and A.E. Grosz, et al. 2014. "Characterization of natural titanomagnetites (Fe3-xTixO4) for studying heterogeneous electron transfer to Tc(VII) in the Hanford subsurface." Geochimica et Cosmochimica Acta 128. PNNL-SA-100342. doi:10.1016/j.gca.2013.12.010
• Qafoku O., J.Z. Hu, N.J. Hess, M.Y. Hu, E.S. Ilton, J. Feng, and B.W. Arey, et al. 2014. "Formation of Submicron Magnesite during Reaction of Natural Forsterite in H2O-Saturated Supercritical CO2." Geochimica et Cosmochimica Acta 134. PNNL-SA-93839. doi:10.1016/j.gca.2013.09.024

2013

• Arey B.W., L. Kovarik, O. Qafoku, Z. Wang, N.J. Hess, and A.R. Felmy. 2013. "Identification of Fragile Microscopic Structures during Mineral Transformations in Wet Supercritical CO2." Microscopy and Microanalysis 19, no. 2:268-275. PNNL-SA-83815. doi:10.1017/S1431927612014171
• Rother G., E.S. Ilton, D. Wallacher, T. Hauss, H.T. Schaef, O. Qafoku, and K.M. Rosso, et al. 2013. "CO2 Sorption to Subsingle Hydration Layer Montmorillonite Clay Studied by Excess Sorption and Neutron Diffraction Measurements." Environmental Science & Technology 47, no. 1:205-211. PNNL-SA-90289. doi:10.1021/es301382y
• Shao H., C.J. Thompson, O. Qafoku, and K.J. Cantrell. 2013. "In Situ Spectrophotometric Determination of pH under Geologic CO2 Sequestration Conditions: Method Development and Application." Environmental Science & Technology 47, no. 1:63-70. PNNL-SA-87968. doi:10.1021/es3016793

2012

• Felmy A.R., D.A. Moore, C.I. Pearce, S.D. Conradson, O. Qafoku, E.C. Buck, and K.M. Rosso, et al. 2012. "Controls on Soluble Pu Concentrations in PuO2/Magnetite Suspensions." Environmental Science & Technology 46, no. 21:11610-11617. PNNL-SA-83931. doi:10.1021/es3028956
• Felmy A.R., O. Qafoku, B.W. Arey, J.Z. Hu, M.Y. Hu, H.T. Schaef, and E.S. Ilton, et al. 2012. "Reaction of Water-Saturated Supercritical CO2 with Forsterite: Evidence for Magnesite Formation at Low Temperatures." Geochimica et Cosmochimica Acta 91. PNNL-SA-82433. doi:10.1016/j.gca.2012.05.026
• Ilton E.S., H.T. Schaef, O. Qafoku, K.M. Rosso, and A.R. Felmy. 2012. "In Situ X-Ray Diffraction Study of Na+ Saturated Montmorillonite Exposed to Variably Wet Super Critical CO2." Environmental Science & Technology 46, no. 7:4241-4248. PNNL-SA-85184. doi:10.1021/es300234v
• Ilton E.S., Z. Wang, J.F. Boily, O. Qafoku, K.M. Rosso, and S.C. Smith. 2012. "The Effect of pH and Time on the Extractability and Speciation of Uranium(VI) Sorbed to SiO2." Environmental Science & Technology 46, no. 12:6604-6611. PNNL-SA-84633. doi:10.1021/es300501v
• Liu J., C.I. Pearce, O. Qafoku, E. Arenholz, S.M. Heald, and K.M. Rosso. 2012. "Tc(VII) Reduction Kinetics by Titanomagnetite (Fe3-xTixO4) Nanoparticles." Geochimica et Cosmochimica Acta 92. PNNL-SA-86376. doi:10.1016/j.gca.2012.06.004
• Loring J.S., H.T. Schaef, R.V. Turcu, C.J. Thompson, Q. Miller, P.F. Martin, and J.Z. Hu, et al. 2012. "In Situ Molecular Spectroscopic Evidence for CO2 Intercalation into Montmorillonite in Supercritical Carbon Dioxide." Langmuir 28, no. 18:7125-7128. PNNL-SA-86500. doi:10.1021/la301136w
• Pearce C.I., O. Qafoku, J. Liu, E. Arenholz, S.M. Heald, R.K. Kukkadapu, and C.A. Gorski, et al. 2012. "Synthesis and properties of titanomagnetite (Fe3-xTixO4) nanoparticles: A tunable solid-state Fe(II/III) redox system." Journal of Colloid and Interface Science 387, no. 1:24-38. PNNL-SA-86362. doi:10.1016/j.jcis.2012.06.092
• Qafoku O., L. Kovarik, R.K. Kukkadapu, E.S. Ilton, B.W. Arey, J. Tucek, and A.R. Felmy. 2012. "Fayalite Dissolution and Siderite Formation in Water-Saturated Supercritical CO2." Chemical Geology 332-333. PNNL-SA-90841. doi:10.1016/j.chemgeo.2012.09.028
• Schaef H.T., E.S. Ilton, O. Qafoku, P.F. Martin, A.R. Felmy, and K.M. Rosso. 2012. "In situ XRD Study of Ca2+ Saturated Montmorillonite (STX-1) Exposed to Anhydrous and Wet Supercritical Carbon Dioxide." International Journal of Greenhouse Gas Control 6, no. 1:220-229. PNNL-SA-80472. doi:10.1016/j.ijggc.2011.11.001

2011

• Felmy A.R., D.A. Moore, K.M. Rosso, O. Qafoku, D. Rai, E.C. Buck, and E.S. Ilton. 2011. "Heterogeneous Reduction of PuO2 with Fe(II): Importance of the Fe(III) Reaction Product." Environmental Science & Technology 45, no. 9:3952-3958. PNNL-SA-76908.

2010

• Hixon A.E., Y. Hu, D.I. Kaplan, R.K. Kukkadapu, H. Nitsche, O. Qafoku, and B.A. Powell. 2010. "Influence of Iron Redox Transformations on Plutonium Sorption to Sediments." Radiochimica Acta 98, no. 9-11:685-692. PNNL-SA-70518. doi:10.1524/ract.2010.1769
• Sullivan R., R. Sullivan, M.J. Moore, M.D. Petters, S.M. Kreidenweis, O. Qafoku, and A. Laskin, et al. 2010. "Impact of Particle Generation Method on the Apparent Hygroscopicity of Insoluble Mineral Particles." Aerosol Science and Technology 44, no. 10:830-846. PNNL-SA-74273. doi:10.1080/02786826.2010.497514

2008

• Hess N.J., O. Qafoku, Y. Xia, D.A. Moore, and A.R. Felmy. 2008. "Thermodynamic Model for Solubility of TcO2·xH2O in Aqueous Oxalate System." Journal of Solution Chemistry 37, no. 11:1471-1487. PNNL-SA-59766. doi:10.1007/s10953-008-9328-5

2007

• Boily J.F., O. Qafoku, and A.R. Felmy. 2007. "A Potentiometric, Spectrophotometric and Pitzer Ion-Interaction Study of Reaction Equilibria in the Aqueous H+-Al3+, H+-Oxalate and H+-Al3+-Oxalate Systems up to 5 mol*dm-3 NaCl." Journal of Solution Chemistry 36, no. 11-12:1727-1743. PNNL-SA-51887. doi:10.1007/s10953-007-9203-9
• Qafoku N., O. Qafoku, C.C. Ainsworth, A. Dohnalkova, and S.G. McKinley. 2007. "Fe-Solid Phase Transformations Under Highly Basic Conditions." Applied Geochemistry 22, no. 9:2054-2064. PNNL-SA-51570. doi:10.1016/j.apgeochem.2007.04.023
• Qafoku O., and A.R. Felmy. 2007. "Development of Accurate Chemical Equilibrium Models for Oxalate Species to High Ionic Strength in the System: Na-Ba-Ca-Mn-Sr-Cl-NO3-PO4-SO4-H2O at 25°C." Journal of Solution Chemistry 36, no. 1:81-95. PNNL-SA-48228.

2006

• Deng Y., M. Flury, J.B. Harsh, A.R. Felmy, and O. Qafoku. 2006. "Cancrinite and Sodalite Formation in the Presence of Cesium, Potassium, Magnesium, Calcium and Strontium in Hanford Tank Waste Simulants." Applied Geochemistry 21, no. 12:2049-2063. PNNL-SA-54132.

2005

• Felmy A.R., M.J. Mason, O. Qafoku, and D.A. Dixon. 2005. "Development of Accurate Chemical Equilibrium Models for the Hanford Waste Tanks: The System Na-Ca-Sr-OH-CO3-NO3-EDTA-HEDTA-H2O from 25 to 75°C." In ACS Symposium Series. 251-281. Washington, District Of Columbia:American Chemical Society. PNNL-SA-42158.
• Qafoku N., J.M. Zachara, C. Liu, P.L. Gassman, O. Qafoku, and S.C. Smith. 2005. "Kinetic Desorption and Sorption of U(VI) During Reactive Transport in a Contaminated Hanford Sediment." Environmental Science & Technology 39, no. 9:3157-3165. PNNL-SA-42960. doi:10.1021/es048462q
• Wang Z., A.R. Felmy, Y. Xia, O. Qafoku, W. Yantasee, and H.M. Cho. 2005. "Complexation of Cm(III)/Eu(III) with Silicate in Basic Solutions." Radiochimica Acta 93, no. 12:741-748. PNNL-SA-42709.
• Wang Z., J.M. Zachara, P.L. Gassman, C. Liu, O. Qafoku, W. Yantasee, and J.G. Catalano. 2005. "Fluorescence Spectroscopy of U(VI)-Silicates and U(VI)-Contaminated Hanford Sediment." Geochimica et Cosmochimica Acta 69, no. 6:1391-1403. PNNL-SA-42812. doi:10.1016/j.gca.2004.08.028

2004

• Felmy A.R., and O. Qafoku. 2004. "An Aqueous Thermodynamic Model for the Complexation of Nickel with EDTA Valid to high Base Concentration." Journal of Solution Chemistry 33, no. 9:1161-1180. PNNL-SA-40706. doi:10.1023/B:JOSL.0000048051.48779.0c
• Liu C., J.M. Zachara, O. Qafoku, J.P. McKinley, S.M. Heald, and Z. Wang. 2004. "Dissolution of Uranyl Microprecipitates from Subsurface Sediments at Hanford Site, USA." Geochimica et Cosmochimica Acta 68, no. 22:4519-4537. PNNL-SA-41756.
• Qafoku N., C.C. Ainsworth, J.E. Szecsody, and O. Qafoku. 2004. "Transport-controlled kinetics of dissolution and precipitation in the sediments under alkaline and saline conditions." Geochimica et Cosmochimica Acta 68, no. 14:2981-2995. PNNL-SA-38913.
• Zachara J.M., C.C. Ainsworth, G.E. Brown, J.G. Catalano, J.P. McKinley, O. Qafoku, and S.C. Smith, et al. 2004. "Chromium Speciation and Mobility in a High Level Nuclear Waste Vadose Zone Plume." Geochimica et Cosmochimica Acta 68, no. 1:13-30. PNNL-SA-36806.

2003

• Felmy A.R., M.J. Mason, and O. Qafoku. 2003. "An Aqueous Thermodynamic Model for the Complexation of Sodium and Strontium with Organic Chelators valid to High Ionic Strength. II. N-(2-hydroxyethyl)ethylenedinitrilotriacetic acid (HEDTA)." Journal of Solution Chemistry 32, no. 4:301-318. PNNL-SA-37212.
• Liu C., J.M. Zachara, O. Qafoku, and S.C. Smith. 2003. "Effect of Temperature on Cs+ Sorption and Desorption in Subsurface Sediments at Hanford Site, U.S.A." Environmental Science & Technology 37, no. 12:2640-2645. PNNL-SA-37351.
• Qafoku N., C.C. Ainsworth, J.E. Szecsody, and O. Qafoku. 2003. "Aluminum Effect on Dissolution and Precipitation under Hyperalkaline Conditions: I. Liquid Phase Transformations." Journal of Environmental Quality 32, no. 6:2354-2369. PNNL-SA-36190.
• Qafoku N., C.C. Ainsworth, J.E. Szecsody, D.L. Bish, J.S. Young, D.E. McCready, and O. Qafoku. 2003. "Aluminum Effect on Dissolution and Precipitation under Hyperalkaline Conditions: II. solid Phase Transformations." Journal of Environmental Quality 32, no. 6:2364-2372. PNNL-SA-36191.
• Qafoku N., C.C. Ainsworth, J.E. Szecsody, O. Qafoku, and S.M. Heald. 2003. "Effect of Coupled Dissolution and Redox Reactions on Cr(VI)(aq) Attenuation during Transport in the Sediments under Hyperalkaline Conditions." Environmental Science & Technology 37, no. 16:3640-3646. PNNL-SA-36318.