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Comparison of leaching tests to determine and quantify the release of inorganic contaminants in demolition waste 总被引:1,自引:0,他引:1
The changes in waste management policy caused by the massive generation of waste materials (e.g. construction and demolition waste material, municipal waste incineration products) has led to an increase in the reuse and recycling of waste materials. For environmental risk assessment, test procedures are necessary to examine waste materials before they can be reused. In this article, results of column and lysimeter leaching tests having been applied to inorganic compounds in a reference demolition waste material are presented. The results show a good agreement between the leaching behaviour determined with the lysimeter unit and the column units used in the laboratory. In view of less time and system requirements compared to lysimeter systems, laboratory column units can be considered as a practicable instrument to assess the time-dependent release of inorganic compounds under conditions similar to those encountered in a natural environment. The high concentrations of elements in the seepage water at the initial stage of elution are reflected by the laboratory column leaching tests. In particular, authorities or laboratories might benefit and have an easy-to-use, but nevertheless reliable, method to serve as a basis for decision-making. 相似文献
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Radiation fog is an important modifier of atmosphericcompounds in the planetary boundary layer. In vegetated areas effects are especially pronounced due to the enlarged surface area. Besides affectingthe lower boundary of atmospheric models fog acts as amulti-phase reaction chamber leading to acid deposition. Here we present the 1-dimensional radiation fog modelCHEMIFOG_V to simulate regional radiation fogevents. The key feature of the fog model is thedetailed microphysics, where the aerosol/dropletspectrum is describedwith a joint 2-dimensional distribution, but also thedynamics, thermodynamics, and radiative transfer are calculated. Toinvestigate the interaction between fog and the biosphere amulti-layer vegetation module, including a soil module as well as a drydeposition module were coupled. Vegetation influences thedynamics, thermodynamics, and the radiation field of the lowestatmospheric layers. With CHEMIFOG_V, numerical case studieson dry and moist deposition processes on vegetation surfaces wereperformed. Hereby multi-phase chemistry and the processing of aerosolswere considered. The results show that the chemical composition of thedeposited fog droplets is mainly determined by the aerosol composition. Dry deposition fluxes are dependent on the incoming radiation and the leaves' surface conditions with respect to water coverage.Due to chemical aerosol processing and deposition, the aerosol spectrumis significantly modified in the planetary boundary layer. 相似文献
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The paper investigates the scientific knowledge divide in the environmental sciences between developed and developing countries and explores the implications and impacts on both science and policymaking. Quantitative data analysis of more than 6400 scientific papers published in 1993–2003 yield evidence for a growing divide in authorship, publication rates, and location of scientific research in nine environmental journals with high impact factor ratings. In addition to this severe imbalance in publication rates between developed and developing countries, we also find a research bias toward certain eco-climatic zones. More than 80% of papers are published in and about temperate and cold eco-climatic zones. Only 13% of the papers in our study are based on research in the dry sub-tropical and tropical zones, although these eco-climatic zones account for more than 52% of the world's land area. Based on these results, we discuss how the limited empirical source and focus of environmental research undermine the claims of universality of environmental science and what consequences this may have on policymaking processes at different levels. Finally, we briefly explore some short- and long-term strategies to address the knowledge divide. 相似文献
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Tanja Barth 《Chemosphere》1984,13(1):67-86
The concentration of oil derived material in the water column under an oil slick has been monitored. In an enclosed natural ecosystem the composition of the material in the water column was found, by liquid chromatography, to be dominated by polar degradation products, indicating that photooxidation of oil hydrocarbons is a major degradation pathway. 相似文献
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Bacteria associated with oak and ash on a TCE-contaminated site: characterization of isolates with potential to avoid evapotranspiration of TCE 总被引:1,自引:0,他引:1
Nele Weyens Safiyh Taghavi Tanja Barac Daniel van der Lelie Jana Boulet Tom Artois Robert Carleer Jaco Vangronsveld 《Environmental science and pollution research international》2009,16(7):830-843
Background, aim, and scope
Along transects under a mixed woodland of English Oak (Quercus robur) and Common Ash (Fraxinus excelsior) growing on a trichloroethylene (TCE)-contaminated groundwater plume, sharp decreases in TCE concentrations were observed, while transects outside the planted area did not show this remarkable decrease. This suggested a possibly active role of the trees and their associated bacteria in the remediation process. Therefore, the cultivable bacterial communities associated with both tree species growing on this TCE-contaminated groundwater plume were investigated in order to assess the possibilities and practical aspects of using these common native tree species and their associated bacteria for phytoremediation. In this study, only the cultivable bacteria were characterized because the final aim was to isolate TCE-degrading, heavy metal resistant bacteria that might be used as traceable inocula to enhance bioremediation. 相似文献20.
Despite the importance of safety climate assessment in healthcare, the psychometric properties of existing safety climate surveys have seldom been tested. We developed a German version of the HSOPSC and investigated its dimensionality and predictive validity. In adapting the survey we differentiated between the two management levels (hospital, unit) by duplicating dimensions of the HSOPSC. Based on a sample of n = 568, confirmatory and exploratory factor analyses (CFA, EFA) were applied. Relationships between safety climate and outcome variables were investigated by regression analyses. CFA did not replicate the proposed factor structure, supporting evidence from other European countries. EFAs revealed eight factors (instead of twelve proposed for the original instrument) and allowed for differentiating between management levels (hospital, unit). For physicians and nurses, different predictors were identified for overall safety climate perception. Further cross-cultural investigations of dimensionality are necessary for international comparisons of safety climate in healthcare. Our results highlight the importance of capturing the impact of different management levels, especially in large hospitals, and differences between professional groups in order to design interventions accordingly. 相似文献