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Influence of polyacrylamide application to soil on movement of microorganisms in runoff water
2000
Sojka, R.E. | Entry, J.A.
Polyacrylamide (PAM) use in irrigation for erosion control has increased water infiltration and reduced soil erosion. This has improved runoff water quality via lower concentrations of nitrogen, phosphorous, and pesticides, and decreased biological oxygen demand. Since non-toxic high molecular weight anionic PAMs removed clay size sediment particles in flowing water, it was hypothesized that PAM would effectively remove or immobilize microorganisms in flowing water. In an agricultural field at the USDA Agricultural Research Service, Idaho, USA, the efficacy of PAM-treatment of furrow irrigation water to remove several categories of microorganisms in the inflow and runoff was determined. Treatments were: (1) PAM application and a control; (2) three flow rates; (3) two distances from the inflow point; and (4) three times during each irrigation. After water travelled 1 m at 7.5 and 15.5/min, PAM-treatment reduced total bacterial and microbial biomass and total fungal biomass relative to the control treatment. After water travelled 40 m at 7.5, 15.5, and 22.5/min, PAM-treatment reduced algae, the numbers active and total bacteria, active and total fungal length, and total bacterial biomass, total fungal and microbial biomass relative to the control treatment. Although specific organisms were not identified or monitored in this study, the results clearly have implications for controlling the spread of soil-borne plant pathogens and other classes of harmful organisms within and among fields via irrigation water and in re-utilized return flows. Beyond furrow-irrigated agriculture, new methods to manage overland transmission of harmful microorganisms could potentially help control transport of pathogens from animal waste in runoff and groundwater.
اظهر المزيد [+] اقل [-]Air pollution engineering manual
2000
Davis, Wayne T.
This manusl characterizes air pollutant emission sources and the technology available to control them. It provides industry and government with the guidelines to comply with air pollution standards and equipment used for gases and particulates.
اظهر المزيد [+] اقل [-]Elsevier's dictionary of marine pollution | Diccionario de contaminación del mar
2000
Zilberberg, Louis-Jacques
The war in Kosovo : Evidence of pollution transport in the Balkans during operation “Allied Force”
2000
Melas, Dimitrios | Zerefos, Christos | Rapsomanikis, Spyros | Tsangas, Nikolaos | Alexandropoulou, Alexandra
During the operation “Allied Force” in the spring of 1999, the burning or damaging of industrial and military targets in the Former Republic of Yugoslavia resulted in the release of a large number of chemicals into the atmosphere. The releases contained not only conventional air pollutants, but also Semi-Volatile Organic compounds (SVOs) which are known to be hazardous to health. Under suitable meteorological conditions, these chemicals can be transported across borders over large distances. In this paper, an analysis of measurements and dispersion calculations is presented which provides evidence of pollutant transport from the conflict area to Greece. The measuring program was carried out in Xanthi, Greece and included aerosol sampling and subsequent analysis for the determination of the concentration of SVOs including dioxins, furans, PCBs (PolyChlorinated Biphenyls), PAHs (Polycyclic Aromatic Hydrocarbons) and organic phthalates.This paper focuses on two episodes of organic phthalates that were observed during the conflict period. Pollution measurements are interpreted by means of air trajectories and dispersion calculations. For this purpose, the HYSPLIT_4 (HYbrid Single-Particle Langrangian Integrated Trajectory) modeling system is used to calculate the dispersion of toxic substances.
اظهر المزيد [+] اقل [-]Biodegradation of superabsorbent polymers in soil
2000
Stahl, James D. | Cameron, Michael D. | Haselbach, Joachim | Aust, Steven D.
Biodegradation of two superabsorbent polymers, a crosslinked, insoluble polyacrylate and an insoluble polyacrylate/ polyacrylamide copolymer, in soil by the white-rot fungus, Phanerochaete chrysosporium was investigated. The polymers were both solubilized and mineralized by the fungus but solubilization and mineralization of the copolymer was much more rapid than of the polyacrylate. Soil microbes poorly solublized the polymers and were unable to mineralize either intact polymer. However, soil microbes cooperated with the fungus during polymer degradation in soil, with the fungus solubilizing the polymers and the soil microbes stimulating mineralization. Further, soil microbes were able to significantly mineralize both polymers after solubilization by P. chrysosporium grown under conditions that produced fungal peroxidases or cellobiose dehydrogenase, or after solubilization by photochemically generated Fenton reagent. The results suggest that biodegradation of these polymers in soil is best under conditions that maximize solubilization.
اظهر المزيد [+] اقل [-]Residues of p,p’-DDT and hexachlorobenzene in human milk from Indonesian women
2000
Shaw, Ian | Burke, Emma | Suharyanto, Frans | Sihombing, Geertruida
Milk from Indonesian women (n = 4) was analysed for p,p’-DDT and the fungicide, hexachlorobenzene (HCB). p,p’-DDT was found in all of the samples and at levels that are amongst the highest reported anywhere in the world in 3 of the samples. HCB was found in all 4 samples, 1 sample had an exceptionally high level. The high residue of HCB suggested exposure by eating dressed grain, major environmental contamination or direct exposure when handling the fungicide. These are the first data on pesticide residues in milk from Indonesian women which demonstrate general exposure to p,p’-DDT and HCB.
اظهر المزيد [+] اقل [-]Remediation engineering of contaminated soils
2000
Wise, Donald L. (Donald Lee)
Offers thorough coverage of the remediation of soils contaminated by hazardous wastes, including materials, analytical techniques, cleanup design and methodology, characterization of geomedia, monitoring of contaminants in the subsurface, and waste containment. Cites specific case studies in hydrocarbon remediation that offer a concise overview of possible technological approaches.
اظهر المزيد [+] اقل [-]Multidimensional risk analysis of antifouling biocides
2000
Ranke, Johannes | Jastorff, Bernd
In order to improve the orientation about the long-term sustainability of the use of the antifouling biocides tributyltin (TBT), copper, Irgarol® 1051, Sea-Nine™ 211 and zinc pyrithione, used for the protection of fouling in sea-going ships, the risks posed to the marine biosphere due to their use are evaluated. The newly presented method of risk analysis uses release rate, spatiotemporal range, bioaccumulation, bioactivity and uncertainty as 5 dimensions of ecotoxicological risk. For each dimension, a scoring procedure is briefly described. The resulting risk profiles of the antifouling biocides show characteristics of the different substances, but also indicate where further information is required. Application of the method is proposed as a decision support in the integrated development of products, informed purchasing and for regulatory purposes.
اظهر المزيد [+] اقل [-]The Interuniversity Consortium, Chemistry for the Environment (INCA)
2000
Tundo, Pietro
The Interuniversity Consortium, Chemistry for the Environment (INCA), was founded in Venice in October 1993. It groups about thirty Italian universities and relies on the research contributions of chemists having different specialities (environmental, physical-chemical, organic, inorganic, analytic, industrial and biochemical), together with researchers coming from other disciplines engaged in environmental research. Consortium INCA has its administrative offices in Venice.
اظهر المزيد [+] اقل [-]SCRAM: A scoring and ranking system for persistent, bioaccumulative, and toxic substances for the North American Great Lakes : Part I: Structure of the scoring and ranking system [ESPR 7 (1) 51–61 (2000)] Part II: Bioaccumulation potential and persistence [ESPR 7 (2) 115–121 (2000)] Part III: Acute and subchronic or chronic toxicity Part IV: Results from representative chemicals, sensitivity analysis, and discriminatory power
2000
Snyder, Erin M. | Snyder, Shane A. | Giesy, John P. | Blonde, Shari A. | Hurlburt, Gary K. | Summer, Cheryl L. | Mitchell, Rachel R. | Bush, Dennis M.
Part I (SNYDER ET AL., 1999a) of this series introduced SCRAM, a chemical scoring and ranking system for contaminants of the North American Great Lakes. Here, in Part II, scoring of the bioaccumulation potential and persistence of chemicals is discussed, including acceptable types of data, specific scoring instructions, and the basis for criteria and scores for these categories of the system. Difficulties encountered during the process of determining which types of data adequately represent the properties of interest are discussed. Also, justification is given for an emphasis on scoring on the basis of persistence.
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