Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Environmental science & technology 26 (1992), S. 925-929 
    ISSN: 1520-5851
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Environmental science & technology 26 (1992), S. 205-207 
    ISSN: 1520-5851
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Environmental science & technology 25 (1991), S. 1062-1067 
    ISSN: 1520-5851
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Environmental science & technology 26 (1992), S. 2228-2234 
    ISSN: 1520-5851
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Environmental science & technology 28 (1994), S. 1205-1210 
    ISSN: 1520-5851
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1432-072X
    Keywords: Key wordsDesulfotomaculum ; Arsenate reduction ; Sulfate reduction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A newly discovered arsenate-reducing bacterium, strain OREX-4, differed significantly from strains MIT-13 and SES-3, the previously described arsenate-reducing isolates, which grew on nitrate but not on sulfate. In contrast, strain OREX-4 did not respire nitrate but grew on lactate, with either arsenate or sulfate serving as the electron acceptor, and even preferred arsenate. Both arsenate and sulfate reduction were inhibited by molybdate. Strain OREX-4, a gram-positive bacterium with a hexagonal S-layer on its cell wall, metabolized compounds commonly used by sulfate reducers. Scorodite (FeAsO42· H2O) an arsenate-containing mineral, provided micromolar concentrations of arsenate that supported cell growth. Physiologically and phylogenetically, strain OREX-4 was far-removed from strains MIT-13 and SES-3: strain OREX-4 grew on different electron donors and electron acceptors, and fell within the gram-positive group of the Bacteria, whereas MIT-13 and SES-3 fell together in the ɛ-subdivision of the Proteobacteria. Together, these results suggest that organisms spread among diverse bacterial phyla can use arsenate as a terminal electron acceptor, and that dissimilatory arsenate reduction might occur in the sulfidogenic zone at arsenate concentrations of environmental interest. 16S rRNA sequence analysis indicated that strain OREX-4 is a new species of the genus Desulfotomaculum, and accordingly, the name Desulfotomaculum auripigmentum is proposed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1432-072X
    Keywords: Key wordsGeovibrio ; Fe(III) reduction ; Co(III) ; reduction ; Sulfur reduction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A new, phylogenetically distinct, dissimilatory, Fe(III)-reducing bacterium was isolated from surface sediment of a hydrocarbon-contaminated ditch. The isolate, designated strain PAL-1, was an obligately anaerobic, non-fermentative, motile, gram-negative vibrio. PAL-1 grew in a defined medium with acetate as electron donor and ferric pyrophosphate, ferric oxyhydroxide, ferric citrate, Co(III)-EDTA, or elemental sulfur as sole electron acceptor. PAL-1 also used proline, hydrogen, lactate, propionate, succinate, fumarate, pyruvate, or yeast extract as electron donors for Fe(III) reduction. It is the first bacterium known to couple the oxidation of an amino acid to Fe(III) reduction. PAl-1 did not reduce oxygen, Mn(IV), U(VI), Cr(VI), nitrate, sulfate, sulfite, or thiosulfate with acetate as the electron donor. Cell suspensions of PAL-1 exhibited dithionite-reduced minus air-oxidized difference spectra that were characteristic of c-type cytochromes. Analysis of the 16S rRNA gene sequence of PAL-1 showed that the strain is not related to any of the described metal-reducing bacteria in the Proteobacteria and, together with Flexistipes sinusarabici, forms a separate line of descent within the Bacteria. Phenotypically and phylogenetically, strain PAl-1 differs from all other described bacteria, and represents the type strain of a new genus and species, Geovibrio ferrireducens.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1745-6584
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Geosciences
    Notes: Ground water chemistry data collected over a six-year period show that the distribution of contaminants and redox processes in a shallow petroleum hydrocarbon-contaminated aquifer has changed rapidly over time. Shortly after a gasoline release occurred in 1990, high concentrations of benzene were present near the contaminant source area. In this contaminated zone, dissolved oxygen in ground water was depleted, and by 1994 Fe(lll) reduction and sulfate reduction were the predominant terminal electron accepting processes. Significantly, dissolved methane was below measurable levels in 1994, indicating the absence of significant methanogenesis. By 1996, however, depletion of solid-phase Fe(lll)-oxyhydroxides in aquifer sediments and depletion of dissolved sulfate in ground water resulted in the onset of methanogenesis. Between 1996 and 2000, water-chemistry data indicated that methanogenic metabolism became increasingly prevalent. Molecular analysis of 16S-rDNA extracted from sediments shows the presence of a more diverse methanogenic community inside as opposed to outside the plume core, and is consistent with water-chemistry data indicating a shift toward methanogenesis over time. This rapid evolution of redox processes reflects several factors including the large amounts of contaminants, relatively rapid ground water flow (∼0.3 m/day [∼1 foot/day]), and low concentrations of microbially reducible Fe(lll) oxyhydroxides (∼ 1 umol/g) initially present in aquifer sediments. These results illustrate that, under certain hydrologic conditions, redox conditions in petroleum hydrocarbon-contaminated aquifers can change rapidly in time and space, and that the availability of solid-phase Fe(lll)-oxyhydroxides affects this rate of change.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1745-6584
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Geosciences
    Notes: Rates of biodegradation were measured in a petroleum hydrocarbon-contaminated aquifer using a combination of field and laboratory methods. These methods are based on tracking concentration changes of substrates (both electron donors and acceptors) or final products of microbial metabolism over time. Ground water at the study site (Hanahan, South Carolina) is anoxic, and sulfate reduction is the predominant terminal electron accepting process. Laboratory studies conducted with sediment cored from the site showed that 14C-toluene was mineralized to 14CO2 with a first-order degradation rate constant (ktol) of -0.01 d−1 under sulfate-reducing conditions. Under nitrate-amended, Fe(III)-amended, or nonamended (methanogenic) conditions, toluene was not significantly mineralized. 14C-Benzene was degraded at low but measurable rates (kben= -0.003 d−1) under sulfate-reducing conditions whereas degradation under methanogenic conditions was negligible. These results illustrate the extreme sensitivity of laboratory-measured biodegradation rates to terminal electron-accepting conditions, and show the necessity of carefully matching experimental conditions to in situ conditions. Concentration decreases of toluene along aquifer flowpaths, when the uncertainty of ground-water flow velocities was considered, indicated ktol values ranging from -0.0075 to -0.03 d−1. Concentration decreases of sulfate and concentration increases of dissolved inorganic carbon (DIC), when normalized for assumed stoichiometric oxidation of toluene coupled to sulfate reduction, yielded a kso4 range of -0.005 to -0.02 d−1, and a kDIC value range of +0.00075 to +0.003 d−1. Because both laboratory and field methods have numerous sources of uncertainty, a combination of these methods is the most appropriate procedure for evaluating biodegradation rate constants in contaminated ground-water systems.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1745-6584
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Geosciences
    Notes: The Middendorf aquifer of South Carolina exhibits a 40-kilometer-wide zone where dissolved ferrous iron concentrations commonly exceed 1 mg/I. Downgradient of this zone, dissolved iron concentrations decrease to less than 0.05 mg/1. Geochemical and microbiologie evidence indicates that this zonation reflects the competitive exclusion of sulfate-reducing activity by Fe(IH)-reducing bacteria in the high-iron zone and the emergence of sulfate reduction as the predominant process in the low-iron zone. Viable Fe(III)- and sulfate-reducing bacteria coexist throughout the aquifer. However, the observed linear relationship between dissolved iron and dissolved inorganic carbon as well as the lack of sulfate consumption indicates that sulfate-reducing bacteria are much less active than Fe(III)-reducing bacteria in the high-iron zone. Fe(III)-reducing bacteria appear to exclude sulfate-reducing activity by maintaining dissolved hydrogen (˜1.0 nM), formate (˜2.0 μM), and acetate (˜1.0 μM) concentrations at levels lower than thresholds required by sulfate-reducing bacteria. Downgradient of the high-iron zone, Fe(III)-reducing activity becomes limited by a lack of Fe(III) oxyhydroxides as Middendorf sediments become progressively more marine in origin. Hydrogen, formate, and acetate concentrations then increase to levels (˜3.0 nM, ˜10.9, and 2.5 μM, respectively) that allow sulfate-reducing bacteria to become active. Increased sulfide production strips ferrous iron from solution by precipitating ferrous sulfides, and dissolved iron concentrations decrease. The observed high-iron zonation is thus one manifestation of microbial competition for scarce substrates. The wide occurrence of similar water-chemistry patterns implies that microbial competition mechanisms are important to the ground-water geochemistry of many hydrologie systems.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...