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Applied Geology and Geochemistry

Nik Qafoku

Nik Qafoku

Pacific Northwest National Laboratory
PO Box 999
Richland, WA 99352

Biography

Nik Qafoku is a chief scientist and team lead in the Geosciences Group. He received the B.S. degree and the Doctor of Science degree in soil fertility and soil chemistry from the College of Agronomy and Environmental Sciences of the Agricultural University of Tirana, Albania. He served as assistant pedagogue, pedagogue, department head and vice-dean for research of this College. He was then nominated director of the science, research and training directorate of the Department of Agriculture and Food and supervised the research conducted in the research institutes and stations in Albania.

In 1994 he was awarded a Senior Fulbright Scholarship and conducted soil systems modeling work at Virginia Polytechnic Institute and State University. Later that year, he was accepted in the graduate school of the University of Georgia where he studied environmental soil science, applied math and computer science. He graduated in 1998 finishing a double-degree program (M.S. in Applied Mathematics and Computer Sciences and Ph.D. in Environmental Soil Chemistry and Physics). He served as a teaching assistant and received the outstanding graduate teaching award from the University of Georgia. He worked as a postdoctoral research associate from 1999-2000 at the University of Georgia, and joined the PNNL in June of 2000 initially as a postdoctoral researcher. Since then, Nik has been promoted three times to the categories of research scientist and then senior research scientist level III and IV.

Research Interests

  • Transport-controlled mobilization and immobilization of contaminants in heterogeneous environments
  • Elemental cycling in soils and sediments
  • Changes in aquifer geochemistry and contaminant behavior in aquifers exposed to leaking CO2 gas from deep subsurface storage
  • Waste form performance and interactions in different environments

Education and Credentials

  • Ph.D. December 1998, Environmental Soil Chemistry, University of Georgia, Athens, GA
  • M.S. December 1998, Computer Science&Applied Mathematics, University of Georgia, Athens, GA
  • Doctor of Science June 1990, Soil Science, Agricultural University of Tirana, Albania
  • B.S. June 1984, Agronomy, Agricultural University of Tirana, Albania

Affiliations and Professional Service

  • American Chemical Society (since 2001; membership number: 2305157)
  • International Union of Soil Science (since 1994; membership number: 312-37130)
  • Soil Science Society of America (since 1994; membership number: 86341)
  • Geochemical Society of America (since 2001)  
  • American Geophysical Union (since 2002; membership number: 30086002)
  • The Clay Minerals Society (2004-2007; membership number: 300279)

Awards and Recognitions

  • Senior Fulbright Scholar (1994)
  • Outstanding Teaching Assistant Award, University of Georgia (1998)
  • Outstanding Performance Awards, PNNL (2005, 2007 and 2009)
  • Citation of excellence award for associate editor of the Soil Science Society of America Journal (2009)
  • Exceptional Contribution Award, PNNL (2014)
  • EED Paper of Year Award, PNNL (2015)
  • Exceptional Contribution Award, PNNL (2016)
  • EED Paper of Year Award, PNNL (2016)

PNNL Publications

2017

  • Hufschmid RD, CJ Newcomb, JW Grate, JJ De Yoreo, ND Browning, and N Qafoku. 2017. "Direct visualization of aggregate morphology and dynamics in a model soil organic-mineral system." Environmental Science & Technology Letters 4(5):186-191.  doi:10.1021/acs.estlett.7b00068
  • Qafoku N, AR Lawter, DH Bacon, L Zheng, JE Kyle, and CF Brown. 2017. "Review of the Impacts of Leaking CO2 Gas and Brine on Groundwater Quality"." Earth - Science Reviews 169:69-84.  doi:10.1016/j.earscirev.2017.04.010
  • Xu J, H Veeramani, N Qafoku, G Singh, MV Riquelme Breazeal, A Pruden, RK Kukkadapu, BN Gartman, and MF Hochella, Jr. 2017. "Efficacy of Acetate-Amended Biostimulation for Uranium Sequestration: Combined Analysis of Sediment/Groundwater Geochemistry and Bacterial Community Structure." Applied Geochemistry 78:172-185.  doi:10.1016/j.apgeochem.2016.12.024

2016

  • Gartman BN, and N Qafoku. 2016. "Uranium interaction with soil minerals in the presence of co-contaminants: Case Study- subsurface sediments at or below the water table." Chapter 10 in Trace Elements in Waterlogged Soils and Sediments. Advances in Trace Elements in the Environment, ed. J Rinklebe, AS Knox and M Paller, pp. 225-249.  CRC Press, BOCA RATON, FL. 
  • Harvey OR, N Qafoku, KJ Cantrell, MJ Wilkins, and CF Brown. 2016. "Methanogenesis-induced pH-Eh shifts drives aqueous metal(loid) mobility in sulfide mineral systems under CO2 enriched conditions." Geochimica et Cosmochimica Acta 173:232-245.  doi:10.1016/j.gca.2015.11.002
  • Qafoku N, and JE Amonette. 2016. "Iron Oxides." In Encyclopedia of Soil Science. 3rd Edition, vol. 2, ed. Rattan Lal, pp. 1245-1249.  Taylor & Francis Group, BOCA RATON, FL. 
  • Williams BD, JJ Neeway, MMV Snyder, ME Bowden, JE Amonette, BW Arey, EM Pierce, CF Brown, and N Qafoku. 2016. "Mineral Assemblage Transformation of a Metakaolin-based Waste Form After Geopolymer Encapsulation." Journal of Nuclear Materials 473:320-332.  doi:10.1016/j.jnucmat.2015.12.023
  • Andersen A, PN Reardon, SS Chacon, N Qafoku, NM Washton, and M Kleber. 2016. "Protein-mineral Interactions: Molecular Dynamics Simulations Capture Importance of Variations in Mineral Surface Composition and Structure." Langmuir 32(24):6194-6209.  doi:10.1021/acs.langmuir.6b01198
  • Asmussen RM, CI Pearce, AR Lawter, JJ Neeway, BL Miller, BD Lee, NM Washton, JR Stephenson, RE Clayton, ME Bowden, EC Buck, E Cordova, N Qafoku, and BD Williams. 2016. Getter Incorporation into Cast Stone and Solid State CharacterizationsPNNL-25577 Rev. 0;RPT-SLAW-003 Rev A, Pacific Northwest National Laboratory, Richland, WA. 
  • Asmussen RM, JJ Neeway, AR Lawter, TG Levitskaia, WW Lukens, and N Qafoku. 2016. "The Function of Sn(II)-Apatite as a 99-Tc Immobilizing Agent." Journal of Nuclear Materials 480:393-402.  doi:10.1016/j.jnucmat.2016.09.002
  • Asmussen RM, JJ Neeway, AR Lawter, AD Wilson, and N Qafoku. 2016. "Silver Based Getters for 129-I Removal from Low Activity Wastes." Radiochimica Acta 104(12):905-913.  doi:10.1515/ract-2016-2598
  • Bacon DH, N Qafoku, Z Dai, E Keating, and CF Brown. 2016. "Modeling the Impact of Carbon Dioxide Leakage into an Unconfined, Oxidizing Carbonate Aquifer." International Journal of Greenhouse Gas Control 44(2016):290-299.  doi:10.1016/j.ijggc.2015.04.008
  • Neeway JJ, N Qafoku, BD Williams, MMV Snyder, CF Brown, and EM Pierce. 2016. "Evidence of Technetium and Iodine from a Sodalite-Bearing Ceramic Waste Form." Applied Geochemistry 66:210-218.  doi:10.1016/j.apgeochem.2015.12.017
  • Neeway JJ, RM Asmussen, AR Lawter, ME Bowden, WW Lukens, D Sarma, BJ Riley, MG Kanatzidis, and N Qafoku. 2016. "Removal of TcO4- from Representative Nuclear Waste Streams with Layered Potassium Metal Sulfide Materials." Chemistry of Materials 28(11):3976-3983.  doi:10.1021/acs.chemmater.6b01296
  • Qafoku N, and R Sahajpal. 2016. "Subsoil contaminant Cr fate and transport: The complex reality of the Hanford subsurface." Chapter 8 in Trace Elements in Waterlogged Soils and Sediments. Advances in Trace Elements in the Environment, ed. J Rinklebe, AS Knox and M Paller, pp. 163-183.  CRC Press, BOCA RATON, FL. 
  • Van Ranst E, N Qafoku, A Noble, and RK Xu. 2016. "VARIABLE CHARGE SOILS: MINERALOGY AND CHEMISTRY." In Encyclopedia of Soil Science, vol. 3, ed. Rattan Lal, pp. 2432-2439.  Taylor & Francis Group, BOCA RATON, FL. 
  • Xu RK, N Qafoku, E Van Ranst, J Li, and J Jiang. 2016. "Adsorption properties of subtropical and tropical variable charge soils: Implications from climate change and biochar amendment." Chapter 1 in Advances in Agronomy, vol. 135, pp. 1-58.  Elsevier, Amsterdam, , Netherlands.  doi:10.1016/bs.agron.2015.09.001

2015

  • Gartman BN, N Qafoku, JE Szecsody, RK Kukkadapu, Z Wang, DM Wellman, and MJ Truex. 2015. "Uranium Fate in Hanford Sediment Altered by Simulated Acid Waste Solutions ." Applied Geochemistry 63(December 2015):1-9.  doi:10.1016/j.apgeochem.2015.07.010
  • Qafoku N. 2015. "Climate-change effects on soils: Accelerated weathering, soil carbon and elemental cycling." Chapter 2 in Advances in Agronomy , vol. 131, ed. DL Sparks, p. 111-172.  Elsevier, Amsterdam, Netherlands. 
  • Shao H, N Qafoku, AR Lawter, ME Bowden, and CF Brown. 2015. "Coupled Geochemical Impacts of Leaking CO2 and Contaminants from Subsurface Storage Reservoirs on Groundwater Quality ." Environmental Science & Technology 49(13):8202-8209.  doi:10.1021/acs.est.5b01004
  • Lawter AR, N Qafoku, H Shao, DH Bacon, and CF Brown. 2015. "Evaluating Impacts of CO2 and CH4 Gas Intrusion into an Unconsolidated Aquifer: Fate of As and Cd." Frontiers in Environmental Science 3:Article No. 49.  doi:10.3389/fenvs.2015.00049
  • Lawter AR, N Qafoku, G Wang, H Shao, and CF Brown. 2015. "Evaluating Impacts of CO2 Intrusion into an Unconsolidated Aquifer: I. Experimental Data." International Journal of Greenhouse Gas Control 44(2016):323-333.  doi:10.1016/j.ijggc.2015.07.009
  • Mouser PJ, AL N'Guessan, N Qafoku, M Sinha, KH Williams, M Dangelmayr, CT Resch, AD Peacock, Z Wang, LA Figueroa, and PE Long. 2015. "Influence of Carbon and Microbial Community Priming on the Attenuation of Uranium in a Contaminated Floodplain Aquifer." Ground Water 53(4):600-613.  doi:10.1111/gwat.12238
  • Neeway JJ, AR Lawter, RJ Serne, RM Asmussen, and N Qafoku. 2015. "Technetium Getters to Improve Cast Stone Performance." In MRS Proceedings: Scientific Basis for Nuclear Waste Management XXXVIII, vol. 1744, ed. S Gin, R Jubin, J Matyas and E Vance, pp. 43-52.  Materials Research Society , Warrendale, PA.  doi:10.1557/opl.2015.310
  • Neeway JJ, N Qafoku, RJ Serne, AR Lawter, JR Stephenson, WW Lukens, and JH Westsik, Jr. 2015. Evaluation of Technetium Getters to Improve the Performance of Cast StonePNNL-23667 Rev. 1;EMSP-RPT-026 Rev1, Pacific Northwest National Laboratory, Richland, WA. 
  • Qafoku N, JJ Neeway, AR Lawter, TG Levitskaia, RJ Serne, JH Westsik, Jr, and MMV Snyder. 2015. Technetium and Iodine Getters to Improve Cast Stone Performance PNNL-23282 Rev. 1, Pacific Northwest National Laboratory, Richland, WA. 
  • Qafoku N, L Zheng, DH Bacon, AR Lawter, and CF Brown. 2015. A Critical Review of the Impacts of Leaking CO2 Gas and Brine on Groundwater QualityPNNL-24897, Pacific Northwest National Laboratory, Richland, WA. 
  • Reiser JT, L Neill, JL Weaver, B Parruzot, C Musa, JJ Neeway, JV Ryan, N Qafoku, S Gin, and N Wall. 2015. "Glass corrosion in the presence of iron-bearing materials and potential corrosion suppressors." In Scientific Basis for Nuclear Waste Management XXXVIII. MRS Proceedings, vol. 1744, ed. S Gin, R Jubin, J Matyas and E Vance, pp. 139-144.  Materials Research Society, Cambridge, United Kingdom.  doi:10.1557/opl.2015.503
  • Szecsody JE, MJ Truex, L Zhong, JP McKinley, N Qafoku, BD Lee, and SD Saurey. 2015. "Remediation of Technetium in Vadose Zone Sediments Using Ammonia and Hydrogen Sulfide Gases ." Vadose Zone Journal 14(7):, doi:10.2136/vzj2014.09.0134
  • Truex MJ, BD Lee, CD Johnson, N Qafoku, GV Last, MH Lee, and DI Kaplan. 2015. Conceptual Model of Iodine Behavior in the Subsurface at the Hanford SitePNNL-24709, Pacific Northwest National Laboratory, Richland, WA. 
  • Truex MJ, JE Szecsody, N Qafoku, R Sahajpal, L Zhong, AR Lawter, and BD Lee. 2015. Assessment of Hexavalent Chromium Natural Attenuation for the Hanford Site 100 AreaPNNL-24705, Pacific Northwest National Laboratory, Richland, WA. 
  • Wang G, N Qafoku, AR Lawter, ME Bowden, O Harvey, EC Sullivan, and CF Brown. 2015. "Geochemical Impacts of Leaking CO2 from Subsurface Storage Reservoirs to an Unconfined Oxidizing Carbonate Aquifer." International Journal of Greenhouse Gas Control 44(2016):310-322.  doi:10.1016/j.ijggc.2015.07.002
  • Zheng L, N Qafoku, AR Lawter, G Wang, H Shao, and CF Brown. 2015. "Evaluating Impacts of CO2 Intrusion into an Unconsolidated Aquifer: II. Modeling Results." International Journal of Greenhouse Gas Control 44(2016):300-309.  doi:10.1016/j.ijggc.2015.07.001

2014

2013

  • Harvey OR, N Qafoku, KJ Cantrell, GH Lee, JE Amonette, and CF Brown. 2013. "Geochemical Implications of Gas Leakage Associated with Geologic CO2 Storage - A Qualitative Review." Environmental Science & Technology 47(1):23-36.  doi:10.1021/es3029457
  • Neeway JJ, N Qafoku, CF Brown, and RA Peterson. 2013. "Characterization and Leaching Tests of the Fluidized Bed Steam Reforming (FBSR) Waste Form for LAW Immobilization." In Proceedings of the Annual Waste Management Symposium (WM2013): International Collaboration and Continuous Improvement, February 24-28, 2013, Phoenix, Arizona, vol. 3, pp. 2268-2275, Paper No. 13400.  WM Symposia, Tucson, AZ. 
  • Qafoku N, CF Brown, G Wang, EC Sullivan, AR Lawter, OR Harvey, and M Bowden. 2013. Geochemical Impacts of Leaking CO2 from Subsurface Storage Reservoirs to Unconfined and Confined AquifersPNNL-22420, Pacific Northwest National Laboratory, Richland, WA. 
  • Szecsody JE, MJ Truex, N Qafoku, DM Wellman, CT Resch, and L Zhong. 2013. "Influence of Acidic and Alkaline Waste Solution Properties on Uranium Migration in Subsurface Sediments." Journal of Contaminant Hydrology 151:155-175.  doi:10.1016/j.jconhyd.2013.05.009
  • Veeramani H, A Scheinost, N Monsegue, N Qafoku, RK Kukkadapu, M Newville, A Lanzirotti, A Pruden, M Murayama, and MF Hochella, Jr. 2013. "Abiotic Reductive Immobilization of U(VI) by Biogenic Mackinawite." Environmental Science & Technology 47(5):2361-2369.  doi:10.1021/es304025x

2012

  • Harvey OR, N Qafoku, KJ Cantrell, and CF Brown. 2012. Geochemical Implications of CO2 Leakage Associated with Geologic Storage: A ReviewPNNL-21550, Pacific Northwest National Laboratory, Richland, WA. 
  • Qafoku N. 2012. "Impacts of Environmental Nanoparticles on Chemical, Biological and Hydrological Processes in Terrestrial Ecosystems." Chapter 4 in Handbook of Soil Sciences: Resource Management and Environmental Impacts, 2nd Edition, ed. PM Huang, Y Li and ME Sumner, pp. 4.1- 4.17.  CRC Press, Boca Raton, FL. 
  • Campbell KM, RK Kukkadapu, N Qafoku, AD Peacock, E Lesher, KH Williams, JR Bargar, MJ Wilkins, LA Figueroa, J Ranville, J Davis, and PE Long. 2012. "Geochemical, mineralogical and microbiological characteristics of sediment from a naturally reduced zone in a uranium-contaminated aquifer." Applied Geochemistry 27(8):1499-1511.  doi:10.1016/j.apgeochem.2012.04.013
  • Neeway JJ, N Qafoku, BD Williams, MM Valenta, EA Cordova, SC Strandquist, DNC Dage, and CF Brown. 2012. "Single Pass Flow-Through (SPFT) Test Results of Fluidized Bed Steam Reforming (FBSR) Waste Forms used for LAW Immobilization." In Waste Management Symposium (WM 2012): Improving the Future in Waste Management, February 26 - March 1, 2012, Phoenix, Arizona, p. Paper No. 12252.  Waste Management Symposia, Inc., Tucson, AZ. 
  • Neeway JJ, N Qafoku, JH Westsik, Jr, CF Brown, C Jantzen, and EM Pierce. 2012. "Radionuclide and contaminant immobilization in the fluidized bed steam reforming waste products." Chapter 11 in Radioactive Waste, ed. RA Rahman, pp. 239-262.  InTech Europe, Rijeka, Croatia (Local Name: Hrvatska). 
  • Szecsody JE, MJ Truex, L Zhong, TC Johnson, N Qafoku, MD Williams, WJ Greenwood, EL Wallin, JR Bargar, and DK Faurie. 2012. "Geochemical and Geophysical Changes during Ammonia Gas Treatment of Vadose Zone Sediments for Uranium Remediation." Vadose Zone Journal 11(4):, doi:10.2136/vzj2011.0158
  • Um W, HS Chang, JP Icenhower, WW Lukens, RJ Serne, N Qafoku, RK Kukkadapu, and JH Westsik, Jr. 2012. "Iron Oxide Waste Form for Stabilizing 99Tc." Journal of Nuclear Materials 429(1-3):201-209.  doi:10.1016/j.jnucmat.2012.06.004
  • Wang G, RJ Serne, MJ Lindberg, W Um, BN Bjornstad, BD Williams, IV Kutynakov, Z Wang, and N Qafoku. 2012. Uranium in Hanford Site 300 Area: Extraction Data on Borehole SedimentsPNNL-22032, Pacific Northwest National Laboratory, Richland, WA. 

2011

2010

  • Qafoku N, PE Dresel, ES Ilton, JP McKinley, and CT Resch. 2010. "Chromium transport in an acidic waste contaminated subsurface medium: The role of reduction." Chemosphere 81(11):1492-1500.  doi:10.1016/j.chemosphere.2010.08.043
  • Qafoku N. 2010. "Terrestrial nanoparticles and their controls on soil/geo processes and reactions ." Chapter 2 in Advances in Agronomy, vol. 107, ed. Donald Sparks, pp. 33-91.  Academic Press, San Diego, CA. 
  • Cabrera ML, DE Kissel, JR Craig, N Qafoku, N Vaio, JA Rema, and LA Morris. 2010. "Relative Humidity Controls Ammonia Loss from Urea Applied to Loblolly Pine." Soil Science Society of America Journal 74(2):543-549. 
  • Icenhower JP, N Qafoku, JM Zachara, and WJ Martin. 2010. "The Biogeochemistry of Technetium: A review of the behavior of an artificial element in the natural environment." American Journal of Science Vol. 310(8):721-752.  doi:10.2475/08.2010.02
  • Kukkadapu RK, N Qafoku, BW Arey, CT Resch, and PE Long. 2010. "Effect of Extent of Natural Subsurface Bioreduction on Fe-mineralogy of Subsurface Sediments." Journal of Physics: Conference Series 217(1):012047 1-8.  doi:10.1088/1742-6596/217/1/012047
  • Pierce EM, SV Mattigod, JH Westsik, Jr, RJ Serne, JP Icenhower, RD Scheele, W Um, and N Qafoku. 2010. Review of Potential Candidate Stabilization Technologies for Liquid and Solid Secondary Waste StreamsPNNL-19122, Pacific Northwest National Laboratory, Richland, WA. 
  • Szecsody JE, MJ Truex, L Zhong, N Qafoku, MD Williams, JP McKinley, Z Wang, J Bargar, DK Faurie, CT Resch, and JL Phillips. 2010. Remediation of Uranium in the Hanford Vadose Zone Using Ammonia Gas: FY 2010 Laboratory-Scale ExperimentsPNNL-20004, Pacific Northwest National Laboratory, Richland, WA. 
  • Szecsody JE, VR Vermeul, JS Fruchter, MD Williams, ML Rockhold, N Qafoku, and JL Phillips. 2010. Hanford 100-N Area In Situ Apatite and Phosphate Emplacement by Groundwater and Jet Injection: Geochemical and Physical Core AnalysisPNNL-19524, Pacific Northwest National Laboratory, Richland, WA. 
  • Um W, H Chang, JP Icenhower, N Qafoku, SC Smith, RJ Serne, EC Buck, RK Kukkadapu, ME Bowden, JH Westsik, Jr, and WW Lukens. 2010. Immobilization and Limited Reoxidation of Technetium-99 by Fe(II)-GoethitePNNL-19833, Pacific Northwest National Laboratory, Richland, WA. 

2009

  • Qafoku N, PE Dresel, JP McKinley, C Liu, SM Heald, CC Ainsworth, JL Phillips, and JS Fruchter. 2009. "Pathways of aqueous Cr(VI) attenuation in a slightly alkaline oxic subsurface ." Environmental Science & Technology 43(4):1071-1077. 
  • Qafoku N, RK Kukkadapu, JP McKinley, BW Arey, SD Kelly, CM Wang, CT Resch, and PE Long. 2009. "Uranium in Framboidal Pyrite from a Naturally Bioreduced Alluvial Sediment ." Environmental Science & Technology 43(22):8528-8534 .  doi:10.1021/es9017333
  • Fiantis D, M Nelson, E Van Ranst, J Shamshudin, and N Qafoku. 2009. "Chemical Weathering of New Pyroclastic Deposits from Mt. Merapi (Java), Indonesia." Journal of Mountain Science 6(3):240-254. 
  • Qafoku N, L Zhong, CJ Thompson, C Liu, BW Arey, AV Mitroshkov, and RG Riley. 2009. "Physical control on CCl4 and CHCl3 desorption from artificially contaminated and aged sediments with supercritical carbon dioxide ." Chemosphere 74(4):494-500. 
  • Zhong L, N Qafoku, JE Szecsody, PE Dresel, and ZF Zhang. 2009. "Foam Delivery of Calcium Polysulfide to Vadose Zone for Chromium-VI Immobilization: A Laboratory Evaluation." Vadose Zone Journal 8(4):976-985.  doi:10.2136/vzj2008.0124

2008

  • Qafoku N, and JP Icenhower. 2008. "Interactions of Aqueous U(VI) with Soil Minerals in Slightly Alkaline Natural Systems." Re/views in Environmental Science and Bio/technology 7(4):355-380.  doi:10.1007/s11157-008-9137-8
  • Wellman DM, JM Zachara, C Liu, N Qafoku, SC Smith, and SW Forrester. 2008. "Advective Desorption of Uranium (VI) from Contaminated Hanford Vadose Zone Sediments under Saturated and Unsaturated Conditions." Vadose Zone Journal 7(4):1144-1159.  doi:10.2136/vzj2007.0166
  • Dresel PE, N Qafoku, JP McKinley, JS Fruchter, CC Ainsworth, C Liu, ES Ilton, and JL Phillips. 2008. Geochemical Characterization of Chromate Contamination in the 100 Area Vadose Zone at the Hanford SitePNNL-17674, Pacific Northwest National Laboratory, Richland, WA. 
  • Icenhower JP, N Qafoku, WJ Martin, and JM Zachara. 2008. The Geochemistry of Technetium: A Summary of the Behavior of an Artificial Element in the Natural EnvironmentPNNL-18139, Pacific Northwest National Laboratory, Richland, WA. 
  • Ilton ES, N Qafoku, C Liu, DA Moore, and JM Zachara. 2008. "Advective Removal of Intraparticle Uranium from Contaminated Vadose Zone Sediments, Hanford, USA." Environmental Science & Technology 42(5):1565-1571.  doi:10.1021/es071113m
  • Liu C, JM Zachara, N Qafoku, and Z Wang. 2008. "Scale-dependent desorption of uranium from contaminated subsurface sediments." Water Resources Research 44:W08413.  doi:10.1029/2007WR006478
  • Van Ranst E, SR Utami, A Verdoodt, and N Qafoku. 2008. "Mineralogy of a perudic Andosol in central Java, Indonesia." Geoderma 144:379-386. 

2007

  • Qafoku N, CC Ainsworth, and SM Heald. 2007. "Cr(VI) Fate in Mineralogically Altered Sediments by Hyperalkaline Waste Fluids ." Soil Science 172(8):598-613. 
  • Qafoku N, O Qafoku, CC Ainsworth, A Dohnalkova, and SG McKinley. 2007. "Fe-Solid Phase Transformations Under Highly Basic Conditions." Applied Geochemistry 22(9):2054-2064.  doi:10.1016/j.apgeochem.2007.04.023

2005

  • Qafoku N, JM Zachara, C Liu, PL Gassman, O Qafoku, and SC Smith. 2005. "Kinetic Desorption and Sorption of U(VI) During Reactive Transport in a Contaminated Hanford Sediment." Environmental Science and Technology 39(9):3157-3165.  doi:10.1021/es048462q
  • Qafoku N, ME Sumner, and M Toma. 2005. "Ion Transport Dynamics in Acid Variable Charge Subsoils." Soil Science and Plant Nutrition 51(5):601-603. 
  • Zachara JM, JA Davis, C Liu, JP McKinley, N Qafoku, DM Wellman, and SB Yabusaki. 2005. Uranium Geochemistry in Vadose Zone and Aquifer Sediments from the 300 Area Uranium PlumePNNL-15121, Pacific Northwest National Laboratory, Richland, WA. 

2004

  • Qafoku N, CC Ainsworth, JE 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(14):2981-2995. 
  • Qafoku N, E Van Ranst, A Noble, and G Baert. 2004. "Variable Charge Soils: Their Mineralogy, Chemistry and Management ." In Advances in Agronomy, vol. 84, ed. Donald L. Sparks, pp. 159-215.  Academic Press, San Diego, CA. 

2003

  • Qafoku N, CC Ainsworth, JE Szecsody, and O Qafoku. 2003. "Aluminum Effect on Dissolution and Precipitation under Hyperalkaline Conditions: I. Liquid Phase Transformations." Journal of Environmental Quality 32(6):2354-2369. 
  • Qafoku N, CC Ainsworth, JE Szecsody, DL Bish, JS Young, DE McCready, and O Qafoku. 2003. "Aluminum Effect on Dissolution and Precipitation under Hyperalkaline Conditions: II. solid Phase Transformations." Journal of Environmental Quality 32(6):2364-2372. 
  • Qafoku N, CC Ainsworth, JE Szecsody, O Qafoku, and SM Heald. 2003. "Effect of Coupled Dissolution and Redox Reactions on Cr(VI)(aq) Attenuation during Transport in the Sediments under Hyperalkaline Conditions." Environmental Science and Technology 37(16):3640-3646. 
  • Qafoku N, E Van Ranst, A Noble, and G Baert. 2003. "Variable Charge Soils: Mineralogy and Chemistry." In Encyclopedia of Soil Science, ed. Rattan Lal, pp. 1822 - 1829.  Taylor and Francis Group, Oxford, United Kingdom. 

Geosciences

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