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1.
Following the recent Basel Convention, increasing emphasis has been placed on technical co-operation to assist developing countries to put in place effective hazardous waste control measures. ISWA, together with other contributing organizations, held in September 1989 a workshop at which case studies of successful hazardous waste management initiatives were analysed. The workshop indicated that a large number of interrelated measures are needed for effective control of hazardous wastes, and that these are best developed gradually in an evolutionary fashion. Measures used by industrialized countries often need to be further adapted for use in other regions. A number of practical first steps were identified that can be used in all countries to initiate effective control. Some general principles to guide the process of adaptation were also formulated.  相似文献   

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At an excitation wavelength of 320 nm, the ultraviolet fluorescence (UVF) spectra emitted by reference oils dispersed in seawater with mineral fines yielded two important results:
  • (1)Resuspended negatively-buoyant oil–mineral aggregates (OMAs) exhibited maximum fluorescence at an emission wavelength of 450 nm and,
  • (2)the hydrocarbons dispersed and/or dissolved in the seawater that remained after the aggregates had settled out exhibited maximum fluorescence at 355 nm.
Data from UVF analysis (450 nm emission) and microscopical observations of seven reference oils suggest that higher-viscosity oils are less likely to form aggregates with mineral fines. This decline in OMA formation with increased oil viscosity could be predicted from a decrease in the ratio of emission at 450–355 nm. The data suggest that direct UVF spectroscopy of dispersed/dissolved oil and OMAs in seawater can be used to predict and verify the extent of OMA formation.  相似文献   

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Nutrient spiralling measurements were conducted in Lyrebird Creek, a forested stream in the Dandenong Ranges, Victoria, Australia. Spiralling indices from several nutrient (, ) enrichment experiments were correlated with seasonal variation in factors thought to control nutrient uptake, i.e., temperature, light and algal biomass. It was hypothesized that nutrient uptake would be higher in summer as increased temperatures would promote both biotic and abiotic processes and higher light levels in summer would stimulate photosynthesis. However, results did not support this hypothesis. Uptake length for and and uptake velocity were not correlated with chlorophyll-a, light or temperature (r 2 < 0.30, P > 0.1) despite the seasonality of these biophysical factors (r 2 > 0.42, P < 0.02). Lyrebird Creek might had no seasonal trend in nutrient uptake and/or nutrient spiraling measurements only appears suitable for contrasting streams with large differences in biophysical factors that supports biotic and abiotic nutrient processing. In addition, small errors in measuring a nutrient concentration can result in a large range in the estimated S w and increased difficulty in determining significant differences in nutrient spiralling indices.  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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Young rainbow trout were exposed to Norman Wells crude oil for periods as long as 55 d. Mortality was light for the first few days, but it continued throughout exposure with more rapid and increased mortality at the higher exposure levels. The mortality was generally exacerbated by the presence of oil dispersants Corexit 7664 or 9600. Fish surviving the 55-day experiment showed severe fin erosion and apparent ‘flooding’, since mean body water content was increased from about 84% to over 90%. We hypothesize that the oil affected the ability of the fish to regulate their water content.  相似文献   

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Journal of Material Cycles and Waste Management - The polysaccharide chitin (CHIT), extracted mainly from exoskeletons of crustaceans, can be obtained from shrimp fishery waste. It is the source of...  相似文献   

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Journal of Polymers and the Environment - Polymer fractions from a biological matrix have been well-characterized by vibrational spectroscopy, XPS, CP/MAS&nbsp;13C NMR, MALDI-TOF mass...  相似文献   

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Journal of Material Cycles and Waste Management - The use of industrial byproducts as replacement of natural aggregates has been extensively investigated to design eco-friendly roads. One of the...  相似文献   

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Journal of Polymers and the Environment - Industrial effluents and stormwater runoff pose a significant threat to the environment and public health. Consequently, the water quality guidelines set...  相似文献   

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The Oil Pollution Act of 1990 (OPA 90) was largely driven by the catastrophic EXXON VALDEZ tanker spill and several other major tanker spills that followed in 1989. Under the OPA 90 mandate, the US Coast Guard, in partnership with other Federal agencies and industry have implemented a number of initiatives that have significantly enhanced the national oil spill prevention, preparedness and response capability. Declining trends in the volume of oil spilled into US waters indicates that these initiatives are at least in some measure successful.The Coast Guard is now concerned about what the future may hold in terms of oil pollution threats, and prevention, preparedness and response program shortcomings and opportunities in the future. To address this issue, the Coast Guard, in partnership with other National Response Team agencies and industry, is conducting a Broad-Based Programmatic Risk Assessment to develop a comprehensive vision and strategy for the Oil Spill Prevention, Preparedness and Response (OSPPR) Program in the 21st Century. This study will characterize the current and emerging oil spill threats by source category, assess the potential impacts of these threats to define overall risk, and examine the current and projected effectiveness of OSPPR initiatives in minimizing these risks. Key issues, problems and focus areas will be identified and targeted for follow-on risk analysis and management activities by the Coast Guard and agency and industry stakeholders.  相似文献   

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Lindberg  S. E.  Brooks  S.  Lin  C-J.  Scott  K.  Meyers  T.  Chambers  L.  Landis  M.  Stevens  R. 《Water, Air, & Soil Pollution: Focus》2001,1(5-6):295-302
We have measured total gaseous mercury concentrations(Hg°) at Point Barrow, Alaska since September 1998 in aneffort to determine the geographic extent and reaction mechanismof the so-called mercury depletion events (MDE) previouslyreported in the high Arctic at Alert, Canada. Hg° has beensampled now for nearly 2 years at Barrow. In September, 1999, webegan making the first automated measurements of reactive gaseousmercury (RGM) attempted in the Arctic, along with measurements ofHg accumulation in snowpack to determine the fate of the depleted Hg°. During the fall and early winter, Hg°and RGM exhibit only minor variation, Hg° remaining within10% of global background, near 1.6–1.8 ng m-3. The MDEperiods are quite different, however; within days of Arcticsunrise in January, Hg° exhibits major variations from themean, rapidly dropping as low as 0.05 ng m-3 and then cyclingback to typical levels, sometimes exceeding global background. These events continue throughout Arctic spring, then end abruptlyfollowing snowmelt, in early June. Prior to Arctic sunrise, RGMremains near detection (<2 pg m-3), but after sunriseincreases dramatically (to levels as high as 900 pg/m3) insynchrony with the depletion of Hg°. Both phenomenaexhibit a strong diel cycle, in parallel with UV-B. We concludethat MDE's involve rapid in-air oxidation of Hg° to aspecies of RGM by photochemically-driven reactions, probablyinvolving the same reactive bromine and chlorine compoundsinvolved in ozone destruction. Sharp increases in Hg in thesurface snowpack after sunrise coincident with periods of peakRGM suggest surface accumulation of the RGM by dry deposition.  相似文献   

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Australia's National Plan to Combat Pollution of the Sea by Oil and Other Noxious and Hazardous Substances (the National Plan) has operated since 1973. The objectives of the National Plan are based on Australia's obligations as a signatory to the International Convention on Oil Pollution Preparedness, Response and Co-operation 1990 and a responsibility to protect natural and artificial (man made) environments from the adverse effects of oil pollution and minimise those effects where protection is not possible.The Australian Maritime Safety Authority (AMSA) is the managing agency of the National Plan, working together with the States and Northern Territory governments, other Commonwealth agencies, ports, and the shipping, oil and exploration industries, to maximise Australia's marine pollution response capability.The 1990s have been a period of significant change for oil spill response arrangements in Australia. The National Plan was extended in 1998 to cover chemical spills and is currently in the process of implementing the oil spill response incident control system (OSRICS). A fixed wing aerial dispersant spraying capability was implemented in 1996 and a research and development program has been put in place. The development of a computer-based National Oil Spill Response Atlas was a major project completed during 1999.  相似文献   

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Journal of Polymers and the Environment - This work aimed to investigate the biopolyethylene (BioPE)/wood powder (WP) composites compatibilized with polyethylene-grafted maleic anhydride (PE-g-MA),...  相似文献   

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Journal of Material Cycles and Waste Management - ​The present study is concerned with an overview of the main aspects of the selective collection from the municipal solid waste in São...  相似文献   

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Journal of Material Cycles and Waste Management - E-waste is becoming a concern due to its toxic content and serious pollution effect. Many studies have focused on the detrimental impacts of...  相似文献   

20.
Journal of Material Cycles and Waste Management - This study provides an overview of calcium rich industrial wastes usage in construction materials, their properties and different applications...  相似文献   

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