+ Visit NASA.gov + Contact NASA   + Home Select Search Field * All Report - Patent Number Abstract *Accession Number *NASA Center *Author NameDocument IDKeywordsPublication Date *Title * Find Results With All of the words At least one of the words Enter Search Term  within returned results    Search Tips: Use only the fields with * to search NIX collection. Enclose terms in double quotation marks (") to search for exact phrases, ie: "space shuttle". NOTE: Commas and dashes are removed from search term by search engine. Select Reset Search button to start a new search. See Help for more tips. + NASA Center + Publication Year + Subject + Availability Options + Item/Media Type Selected Navigations: Author > Canfield, Donald E. [x] Sort results by: NASA Center | Date Added to NTRS | Publication Year There are a total of 5 record(s) matching your query. Sorted by: Date Added To NTRS in Descending order Ancient sulfur biogeochemistry Author(s): Canfield, Donald E. Abstract: Ancient sulfur isotopic biogeochemistry analysis of sediment and shales samples from the McRae shale site in Western Australia were performed in order to determine the sediment geochemical record of environmental change in ... NASA Center: NASA (non Center Specific) Publication Year: 1995 Added to NTRS: 2005-08-25 Accession Number: 95N71566; Document ID: 19950003446; Report Number: NAS 1.26:199096, NASA-CR-199096 Aerobic sulfate reduction in microbial mats Author(s): Canfield, Donald E.; Des Marais, David J. Abstract: Measurements of bacterial sulfate reduction and dissolved oxygen (O2) in hypersaline bacterial mats from Baja California, Mexico, revealed that sulfate reduction occurred consistently within the well-oxygenated ... NASA Center: Ames Research Center Publication Year: 1991 Added to NTRS: 2004-11-03 Accession Number: 91A31150; Document ID: 19910046527 The anaerobic degradation of organic matter in Danish coastal sediments - Iron reduction, manganese reduction, and sulfate reduction Author(s): Canfield, Donald E.; Thamdrup, BO; Hansen, Jens W. Abstract: A combination of porewater and solid phase analysis as well as a series of sediment incubations are used to quantify organic carbon oxidation by dissimilatory Fe reduction, Mn reduction, and sulfate reduction, in sediments ... NASA Center: NASA (non Center Specific) Publication Year: 1993 Added to NTRS: 2004-11-03 Accession Number: 94A10128; Document ID: 19940033473 Reactive iron in marine sediments Author(s): Canfield, Donald E. Abstract: The influence of reactive iron oxides on sediment pore-water chemistry is considered in detail. A carefully calibrated extraction scheme is used to determine the depth distributions of reactive iron phases at two very ... NASA Center: Ames Research Center Publication Year: 1989 Added to NTRS: 2004-11-03 Accession Number: 89A34617; Document ID: 19890047246 Biogeochemical cycles of carbon, sulfur, and free oxygen in a microbial mat Author(s): Canfield, Donald E.; Des Marais, David J. Abstract: Complete budgets for carbon and oxygen have been constructed for cyanobacterial mats dominated by Microcoleus chthonoplastes from the evaporating ponds of a salt works. We infer from the data the various sinks for O2 as well ... NASA Center: Ames Research Center Publication Year: 1993 Added to NTRS: 2004-11-03 Accession Number: 94A10129; Document ID: 19940033474 + Back to Top + Sponsored by the NASA Scientific and Technical    Information Program + 2004 Vision for Space Exploration + Freedom of Information Act + NASA Web Privacy Policy and Important Notices + NASA Disclaimers, Copyright Notice,    and Terms and Conditions of Use NASA Official: Calvin Mackey Page Curator: NASA Center for AeroSpace Information (help@sti.nasa.gov) Last Updated: July 5, 2007