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Determination of microbial activity in activated sewage sludge by dimethyl sulphoxide reduction - Evaluation of method and application
1994
Sklorz, M. (Bayreuth Univ. (Germany). Lehrstuhl fuer Oekologische Chemie und Geochemie) | Binert, J.
A method was developed to determine the dimethyl sulphoxide (DMSO) reduction rate in activated sewage sludge at nearly natural conditions. Linearity of microbially produced dimethyl sulphide with incubation time and sample size was shown. Apart from a fast, sensitive and highly reproducible automatic analysis of dimethyl sulphide, simultaneous determination of mineralisation, respiration and phenol degradation rates was possible. The DMSO reduction rate of samples taken from a municipal sewage plant ranged between 2 and 3 micromol/(g dry matter per h), respiration and mineralisation rates between 30 and 80 micromol/(g per h). Added (13)C(6)-phenol was completely degradated after 96 h of incubation. A half-life of 14 h was calculated assuming first order decay. Dose response curves were obtained by incubating samples for 2, 6, 25, and 96 hours after addition of pentachlorophenol. At an incubation time of 6 h, the EC(50) values ranged from 20 mg/L (DMSO reduction) to 30 mg/L (phenol degradation) up to 180 mg/L (respiration and mineralisation). Increasing the incubation time to 96 h resulted in a lower EC(50) of 9 mg/L for DMSO reduction, whereas it increased to 500 mg/L for respiration and mineralisation.
Show more [+] Less [-]Lindane residues in the southern coastal aquifer of Israel
1974
Lahav, N. (Hebrew Univ., Rehovoth (Israel). Dept. of Soil and Water) | Kahanovitch, Y.
Effect of silver from cloud seeding on rumen microbial function
1974
Roy, D.R. | Bailey, J.A. (Colorado State Univ., Fort Collins (USA). Dept. of Fishery and Wildlife Biology)
Reactions of cloned poplars to air pollution -Ozone-induced increase of stress ethylene and possible antisenescence strategies
1995
Ballach, H.J. | Niederee, C. | Wittig, R. | Woltering, E.J. (Frankfurt Univ. (Germany). Botanisches Inst.)
Estimation of mercury content in tailings of the gold mine area of Pocone, Mato Grosso, Brazil
1995
Tuempling, W. von Jr. | Zeilhofer, P. | Ammer, U. | Einax, J. | Wilken, R.D. (Institut fuer Physikalische und Chemische Analyse, Geesthacht (Germany))
Evaluation of Fate and Exposure Models - An object-oriented software for fate and exposure assessments
1995
Scheil, S. | Baumgarten, G. | Reiter, B. | Schwartz, S. | Wagner, J.O. | Trapp, S. | Matthies, M. (Osnabrueck Univ. (Germany). Inst. fuer Umweltsystemforschung)
COS, CS2 and SO2 in aluminium smelter exhaust - The contribution of aluminium production to the global COS budget
1995
Harnisch, J. | Borchers, R. | Fabian, P. (Max-Planck-Institut fuer Aeronomie, Katlenburg-Lindau (Germany))
The North Sea - Invisible decline? [Greenpeace report, Short Version]
1995
Johnston, P. | Verbeek, M. | MacGarvin, M. | Simmonds, M. | Mayer, S. | McKay, B. (Exeter Univ. (United Kingdom). Greenpeace Exeter Research Lab.)
Cadmium and methylmercury bioaccumulation by nymphs of the burrowing mayfly Hexagenia rigida from the water column and sediment
1995
Odin, M. | Ribeyre, F. | Boudou, A. (Bordeaux Univ., Talence Cedex (France). Lab. d'Ecotoxicologie)
Ancient atmosphere - Validity of ice records
1994
Jaworowski, Z. (Institutt for Energiteknikk, Kjeller (Norway))
Interpretation of the greenhouse data from the ice cores are sometimes based on rejection of analytical results, and often on assumptions disregarding gas fractionation processes. At present, our understanding of these processes in ice sheets is rather poor. There is a need for experimental studies which would provide the essential physical and chemical parameters needed. Before such studies are carried out, conclusions on low pre-industrial atmospheric levels of greenhouse gases cannot be accepted when deduced from ice core data. High contamination of the inner parts of the ice cores with lead and other metals by the drilling procedure is compelling evidence that the cores do not fulfil the absolutely essential, closed system criterion. Thus, they are not suitable for reconstruction of the composition of pre-industrial and ancient atmosphere.
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