
<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Reinsch, B. C.</style></author><author><style face="normal" font="default" size="100%">Forsberg, B.</style></author><author><style face="normal" font="default" size="100%">Penn, R. L.</style></author><author><style face="normal" font="default" size="100%">Kim, C. S.</style></author><author><style face="normal" font="default" size="100%">Lowry, G. V.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Chemical Transformations during Aging of Zerovalent Iron Nanoparticles in the Presence of Common Groundwater Dissolved Constituents</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental Science &amp; Technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Sci. Technol.</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">DEGRADATION</style></keyword><keyword><style  face="normal" font="default" size="100%">EDGE ABSORPTION-SPECTRA</style></keyword><keyword><style  face="normal" font="default" size="100%">FE MINERALS</style></keyword><keyword><style  face="normal" font="default" size="100%">H-2 EVOLUTION</style></keyword><keyword><style  face="normal" font="default" size="100%">MODEL COMPOUNDS</style></keyword><keyword><style  face="normal" font="default" size="100%">NANOMATERIALS</style></keyword><keyword><style  face="normal" font="default" size="100%">QUANTITATIVE SPECIATION</style></keyword><keyword><style  face="normal" font="default" size="100%">REACTIVE BARRIER</style></keyword><keyword><style  face="normal" font="default" size="100%">SPECTROSCOPY</style></keyword><keyword><style  face="normal" font="default" size="100%">TCE DECHLORINATION</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">May</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">&lt;Go to ISI&gt;://000277067000043 </style></url></web-urls></urls><number><style face="normal" font="default" size="100%">9</style></number><volume><style face="normal" font="default" size="100%">44</style></volume><pages><style face="normal" font="default" size="100%">3455-3461</style></pages><isbn><style face="normal" font="default" size="100%">0013-936X</style></isbn><language><style face="normal" font="default" size="100%">English</style></language><abstract><style face="normal" font="default" size="100%">Nanoscale zerovalent iron (NZVI) that was aged in simulated groundwater was evaluated for alterations in composition and speciation over 6 months to understand the possible transformations NZVI could undergo in natural waters. NZVI was exposed to 10 mN of various common groundwater anions (Cl-, NO3-, SO42-, HPO42-, and HCO3-) or to dissolved oxygen (saturated, similar to 9 mg/L). Fresh and exposed NZVI samples, along with Fe-oxide model compounds, were then analyzed using synchrotron radiation X-ray absorption spectroscopy (XAS) to yield both relative oxidation state, using the X-ray absorption near edge structure (XANES), and quantitative speciation information regarding the types and proportions of mineral species present, from analysis of the extended X-ray absorption fine structure (EXAFS). Over 1 month of aging the dissolved anions inhibited the oxidation of the NZVI to varying degrees. Aging for 6 months, however, resulted in average oxidation states that were similar to each other regardless of the anion used, except for nitrate. Nitrate passivated the NZVI surface such that even after 6 months of aging the particles retained nearly the same mineral and Fe-0 content as fresh NZVI. Linear least-squares combination fitting (LCF) of the EXAFS spectra for 1 month-aged samples indicated that the oxidized particles remain predominantly a binary phase system containing Fe-0 and Fe3O4, while the 6 month aged samples contained additional mineral phases such as vivianite (Fe-3(PO4)(2)center dot 8H(2)O) and iron sulfate species, possibly schwertmannite (Fe163+O16(OH,SO4)(12-13)center dot 10-12H(2)O). The presence of these additional mineral species was confirmed using synchrotron-based X-ray diffraction (XRD). NZVI exposed to water saturated with dissolved oxygen showed a rapid (&lt;24 h) loss of Fe-0 and evolved both magnetite and maghemite (gamma-Fe2O3) within the oxide layer. These findings have implications toward the eventual fate, transport, and toxicity of NZVI used for groundwater remediation.</style></abstract><work-type><style face="normal" font="default" size="100%">Article</style></work-type><accession-num><style face="normal" font="default" size="100%">ISI:000277067000043</style></accession-num><notes><style face="normal" font="default" size="100%">ISI Document Delivery No.: 588JXTimes Cited: 4Cited Reference Count: 40</style></notes><auth-address><style face="normal" font="default" size="100%">[Reinsch, Brian C.; Lowry, Gregory V.] Carnegie Mellon Univ, Dept Civil &amp; Environm Engn, Pittsburgh, PA USA. [Reinsch, Brian C.; Lowry, Gregory V.] CEINT, Pittsburgh, PA 15213 USA. [Forsberg, Brady; Penn, R. Lee] Univ Minnesota, Dept Chem, Minneapolis, MN 55455 USA. [Kim, Christopher S.] Chapman Univ, Dept Chem, Orange, CA 92866 USA.Lowry, GV, Carnegie Mellon Univ, Dept Civil &amp; Environm Engn, 5000 Forbes Ave, Pittsburgh, PA 15213 USA.glowry@andrew.cmu.edu</style></auth-address></record></records></xml>