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[In-well vapor stripping: a new method for in situ purification of contaminated groundwater]
1999
Abraham, A.
[In-situ remediation of three sites polluted with hydrocarbons]
1999
Jeppesen, M.N. | Nielsen, S.T.
[Cultivation agreements: development of a tool to protection of the groundwater]
1999
Vangsgaard, C. | Schroeder, L.
[Pesticides in soil and groundwater at selected nurseries]
1999
Ludvigsen, L. | Kirkegaard, C.
[Natural degradation in groundwater contaminated with benzene and mineral oil and chlorinated solvents]
1999
Bjerg, P.L.
[Technology development project in-well stripping of chlorinated solvents [AIWA, Adept in-Well Aerator]]
1999
Lauridsen, A.E. | Nyegaard, T.
Demonstration of accelerated anaerobic bioremediation of TCE using bioaugmentation
1999
Morgan, P. | Buchanan, R.J. | Bartlett, C.L. | Ellis, D.E. | Hanson, G.J. | Lee, M.D. | Lutz, E.J. | Odorn, J.M. | Harkness, M.A. | DeWeerd, K.A. | Spivack, J.L. | Bell, M.J.
Interactive valuation : the social construction of the value of ecological services
1999
Jiggins, J. | Röling, N.
Using SFA indicators to support environmental policy 全文
1999
van der Voet, Ester | van Oers, Lauran | Guinée, J. B. | de Haes, Helias A Udo
In order to improve the link from Substance Flow Analysis (SFA) studies to environmental policy, a translation is made from the SFA overview of flows and stocks into a limited set of indicators. This set is designed to evaluate a region’s substance regime with regard to environmental quality and sustainable development, including problem shifting in time and space.
显示更多 [+] 显示较少 [-]A review of biomarker compounds as source indicators and tracers for air pollution 全文
1999
Simoneit, Bernd R. T.
An overview of the application of organic geochemistry to the analysis of organic matter on aerosol particles is presented here. This organic matter is analyzed as solvent extractable bitumen/ lipids by gas chromatography-mass spectrometry. The organic geochemical approach assesses the origin, the environmental history and the nature of secondary products of organic matter by using the data derived from specific molecular analyses. Evaluations of production and fluxes, with cross-correlations can thus be made by the application of the same separation and analytical procedures to samples from point source emissions and the ambient atmosphere. This will be illustrated here with typical examples from the ambient atmosphere (aerosol particles) and from emissions of biomass burning (smoke).Organic matter in aerosols is derived from two major sources and is admixed depending on the geographic relief of the air shed. These sources are biogenic detritus (e.g., plant wax, microbes, etc.) and anthropogenic particle emissions (e.g., oils, soot, synthetics, etc.). Both biogenic detritus and some of the anthropogenic particle emissions contain organic materials which have unique and distinguishable compound distribution patterns (C₁₄-C₄₀). Microbial and vascular plant lipids are the dominant biogenic residues and petroleum hydrocarbons, with lesser amounts of the pyrogenic polynuclear aromatic hydrocarbons (PAH) and synthetics (e.g., chlorinated compounds), are the major anthropogenic residues.Biomass combustion is another important primary source of particles injected into the global atmosphere. It contributes many trace substances which are reactants in atmospheric chemistry and soot paniculate matter with adsorbed biomarker compounds, most of which are unknown chemical structures. The injection of natural product organic compounds into smoke occurs primarily by direct volatilization/steam stripping and by thermal alteration based on combustion temperature. Although the molecular composition of organic matter in smoke particles is highly variable, the molecular tracers are generally still source specific. Retene has been utilized as a tracer for conifer smoke in urban aerosols, but is not always detectable. Dehydroabietic acid is generally more concentrated in the atmosphere from the same emission sources. Degradation products from biopolymers (e.g., levoglucosan from cellulose) are also excellent tracers. An overview of the biomarker compositions of biomass smoke types is presented here. Defining additional tracers of thermally-altered and directly-emitted natural products in smoke aids the assessment of the organic matter type and input from biomass combustion to aerosols. The precursor to product approach of compound characterization by organic geochemistry can be applied successfully to provide tracers for studying the chemistry and dispersion of ambient aerosols and smoke plumes.
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