Browsing by Author "Zachara J.M."
- DSpace Home
- →
- Browsing by Author
JavaScript is disabled for your browser. Some features of this site may not work without it.
Browsing by Author "Zachara J.M."
Now showing items 1-18 of 18
-
Zachara J.M.; Smith S.C.; Kuzel L.S. (1995)The sorption of Co(II)EDTA2- (where EDTA is ethylenediaminetetracetic acid) was investigated on goethite and on eight sand-textured Quaternary and Pliocene fluvial sediments. Dual-label tracer techniques were used to follow ...
-
Fredrickson J.K.; Zachara J.M.; Kennedy D.W.; Dong H.; Onstott T.C.; Hinman N.W.; Li S.M. (1998)Dissimilatory iron-reducing bacteria (DIRB) couple the oxidation of organic matter or H2 to the reduction of iron oxides. The factors controlling the rate and extent of these reduction reactions and the resulting solid ...
-
Kukkadapu R.K.; Zachara J.M.; Fredrickson J.K.; Kennedy D.W. (2004)The reductive biotransformation of two Si-ferrihydrite coprecipitates (1 and 5 mole % Si) by Shewanella putrefaciens, strain CN32, was investigated in 1,4-piperazinediethanesulfonic acid-buffered media (pH ∼7) with lactate ...
-
Zachara J.M.; Ainsworth C.C.; McKinley J.P.; Qafoku O.; Smith S.C.; Szecsody J.E.; Brown Jr.G.E.; Catalano J.G.; Warner J.A.; Traina S.J. (2004)Radioactive core samples containing elevated concentrations of Cr from a high level nuclear waste plume in the Hanford vadose zone were studied to asses the future mobility of Cr. Cr(VI) is an important subsurface contaminant ...
-
DiChristina T.J.; Fredrickson J.K.; Zachara J.M. (2005)Dissimilatory metal-reducing bacteria (DMRB) are important components of the microbial community residing in redox-stratified freshwater and marine environments. DMRB occupy a central position in the biogeochemical cycles ...
-
Wang Z.; Zachara J.M.; Gassman P.L.; Liu C.; Qafoku O.; Yantasee W.; Catalano J.G. (2005)Time-resolved U(VI) laser fluorescence spectra (TRLFS) were recorded for a series of natural uranium-silicate minerals including boltwoodite, uranophane, soddyite, kasolite, sklodowskite, cuprosklodowskite, haiweeite, and ...
-
Fredrickson J.K.; Zachara J.M.; Kennedy D.W.; Liu C.; Duff M.C.; Hunter D.B.; Dohnalkova A. (2002)The potential for Mn oxides to modify the biogeochemical behavior of U during reduction by the subsurface bacterium Shewanella putrefaciens strain CN32 was investigated using synthetic Mn(III/IV) oxides (pyrolusite [β-MnO2], ...
-
MICROSCALE CONTROLS ON THE FATE OF CONTAMINANT URANIUM IN THE VADOSE ZONE, HANFORD SITE, WASHINGTON McKinley J.P.; Zachara J.M.; Liu C.; Heald S.C.; Prenitzer B.I.; Kempshall B.W. (2006)An alkaline brine containing uranyl (UO22+) leaked to the thick unsaturated zone at the Hanford Site. We examined samples from this zone at microscopic scale to determine the mode of uranium occurrence-microprecipitates ...
-
Dong H.; Fredrickson J.K.; Kennedy D.W.; Zachara J.M.; Kukkadapu R.K.; Onstott T.C. (2000)Although dissimilatory iron reducing bacteria (DIRB) are capable of reducing a number of metals in oxides and soluble forms, the factors controlling the rate/extent of magnetite reduction and the nature of the mineral ...
-
Rosso K.M.; Zachara J.M.; Fredrickson J.K.; Gorby Y.A.; Smith S.C. (2003)Mechanisms by which dissimilatory iron-reducing bacteria utilize iron and manganese oxide minerals as terminal electron acceptors for respiration are poorly understood. In the absence of exogenous electron shuttle compounds, ...
-
Zachara J.M.; Gassman P.L.; Smith S.C.; Taylor D. (1995)Batch interaction experiments were performed under aerobic conditions to characterize the adsorption behavior and valence speciation of CoEDTA complexes (equimolar at 10-5 mol/L) in a series of Pliocene subsurface sediments ...
-
Fredrickson J.K.; Zachara J.M.; Kennedy D.W.; Kukkadapu R.K.; McKinley J.P.; Heald S.M.; Liu C.; Plymale A.E. (2004)The potential for reduction of 99TcO4−(aq) to poorly soluble 99TcO2 · nH2O(s) by biogenic sediment-associated Fe(II) was investigated with three Fe(III)-oxide containing subsurface materials and the dissimilatory metal-reducing ...
-
Fredrickson J.K.; Zachara J.M.; Kennedy D.W.; Duff M.C.; Gorby Y.A.; Li S.M.W.; Krupka K.M. (2000)Dissimilatory metal-reducing bacteria (DMRB) can utilize Fe(III) associated with aqueous complexes or solid phases, such as oxide and oxyhydroxide minerals, as a terminal electron acceptor coupled to the oxidation of H2 ...
-
Kukkadapu R.K.; Zachara J.M.; Fredrickson J.K.; McKinley J.P.; Kennedy D.W.; Smith S.C.; Dong H. (2006)A <2.0-mm fraction of a mineralogically complex subsurface sediment containing goethite and Fe(II)/Fe(III) phyllosilicates was incubated with Shewanella putrefaciens (strain CN32) and lactate at circumneutral pH under ...
-
Zachara J.M.; Fredrickson J.K.; Smith S.C.; Gassman P.L. (2001)Trace metals associate with Fe(III) oxides as adsorbed or coprecipitated species, and consequently, the biogeochemical cycles of iron and the trace metals are closely linked. This communication investigated the solubilization ...
-
Turner G.D.; Zachara J.M.; McKinley J.P.; Smith S.C. (1996)Surface charge and UO22+ adsorption were measured on a clay-sized, subsurface mineral isolate whose mineralogy was dominated by a ferrogenous beidellite. Experiments were performed in batch at 25°C with N2(g) atmosphere ...
-
Ilton E.S.; Liu C.; Yantasee W.; Wang Z.; Moore D.A.; Felmy A.R.; Zachara J.M. (2006)Uranyl silicates such as uranophane and Na-boltwoodite appear to control the solubility of uranium in certain contaminated sediments at the US Department of Energy Hanford site [Liu, C., Zachara, J.M., Qafoku, O., McKinley, ...
-
Fox P.M.; Davis J.A.; Zachara J.M. (2006)Recent studies of uranium(VI) geochemistry have focused on the potentially important role of the aqueous species, CaUO2 (CO3)32- and Ca2 UO2(CO3)30(aq), on inhibition of microbial reduction and uranium(VI) aqueous speciation ...
Now showing items 1-18 of 18