<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sahu, Ashish K</style></author><author><style face="normal" font="default" size="100%">Conneely, Teresa</style></author><author><style face="normal" font="default" size="100%">Nüsslein, Klaus R</style></author><author><style face="normal" font="default" size="100%">Ergas, Sarina J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Biological perchlorate reduction in packed bed reactors using elemental sulfur.</style></title><secondary-title><style face="normal" font="default" size="100%">Environ Sci Technol</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%">Bacteria</style></keyword><keyword><style  face="normal" font="default" size="100%">Bioreactors</style></keyword><keyword><style  face="normal" font="default" size="100%">Environmental Pollutants</style></keyword><keyword><style  face="normal" font="default" size="100%">Medical Waste Disposal</style></keyword><keyword><style  face="normal" font="default" size="100%">Oxidation-Reduction</style></keyword><keyword><style  face="normal" font="default" size="100%">Perchloric Acid</style></keyword><keyword><style  face="normal" font="default" size="100%">Sulfur</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">43</style></volume><pages><style face="normal" font="default" size="100%">4466-71</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Sulfur-utilizing perchlorate (ClO4-)-reducing bacteria were enriched from a denitrifying wastewater seed with elemental sulfur (S0) as an electron donor. The enrichment was composed of a diverse microbial community, with the majority identified as members of the phylum Proteobacteria. Cultures were inoculated into bench-scale packed bed reactors (PBR) with S0 and crushed oyster shell packing media. High ClO4-concentrations (5-8 mg/L) were reduced to &lt; 0.5 mg/L at an empty bed contact time (EBCT) of 13 h. Low C1O4- concentrations (60-120 microg/L), more typical of contaminated groundwater sites, were reduced to &lt; 4 microg/L at an EBCT of 7.5 h. PBR performance decreased when effluent recirculation was applied or when smaller S0 particle sizes were used, indicating that mass transfer of ClO4- to the attached biofilm was not the limiting mechanism in this process, and that biofilm acclimation and growth were key factors in overall reactor performance. The presence of nitrate (6.5 mg N/L) inhibited ClO4- reduction. The microbial community composition was found to change with ClO4- availability from a majority of Beta-Proteobacteria near the influent end of the reactor to primarily sulfur-oxidizing bacteria near the effluent end of the reactor.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19603663?dopt=Abstract</style></custom1></record></records></xml>