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91.
The COVID-19 pandemic and related social and economic emergencies induced massive public spending and increased global debt. Economic recovery is now an opportunity to rebuild natural capital alongside financial, physical, social and human capital, for long-term societal benefit. Yet, current decision-making is dominated by economic imperatives and information systems that do not consider society’s dependence on natural capital and the ecosystem services it provides. New international standards for natural capital accounting (NCA) are now available to integrate environmental information into government decision-making. By revealing the effects of policies that influence natural capital, NCA supports identification, implementation and monitoring of Green Recovery pathways, including where environment and economy are most positively interlinked.  相似文献   
92.
Directive 2000/53/EC sets a goal of 85% material recycling from end-of-life vehicles (ELVs) by the end of 2015. The current ELV recycling rate is around 80%, while the remaining waste is called automotive shredder residue (ASR), or car fluff. In Europe, this is mainly landfilled because it is extremely heterogeneous and often polluted with car fluids. Despite technical difficulties, in the coming years it will be necessary to recover materials from car fluff in order to meet the ELV Directive requirement. This study deals with ASR pretreatment and pyrolysis, and aims to determine whether the ELV material recycling target may be achieved by car fluff mechanical separation followed by pyrolysis with a bench scale reactor. Results show that flotation followed by pyrolysis of the light, organic fraction may be a suitable ASR recycling technique if the oil can be further refined and used as a chemical. Moreover, metals are liberated during thermal cracking and can be easily separated from the pyrolysis char, amounting to roughly 5% in mass. Lastly, pyrolysis can be a good starting point from a "waste-to-chemicals" perspective, but further research should be done with a focus on oil and gas refining, in order both to make products suitable for the chemical industry and to render the whole recycling process economically feasible.  相似文献   
93.
Polystyrene (PS) is currently used as packaging, insulating and storing material in various industrial or domestic fields. As a result, a large quantity of PS wastes is produced. Plastic wastes are not usually biodegradable, so it is necessary to suggest a technology to recycle them. Landfills and incineration are reasonably cheap methods but are not environmentally acceptable, therefore, alternative methods for polymer recycling are required. The general purpose of PS foam recycling is to recover a more compact polymeric material without degradation. Dissolution with terpenic solvents is presented here as an efficient and cheap alternative that is developed at room temperature; among the oils studied, limonene was selected because of its intermediate solubility and its abundance. The solvent removal is possible thanks to supercritical technology that provides a high solubility in limonene and almost a complete PS insolubility at moderated pressures (77?bar) and low temperatures (30?°C). Thus, based on the results of thermogravimetric and chromatographic analysis, we propose that.supercritical antisolvent precipitation is an ideal technique for carrying out the separation of PS and limonene, providing a recycled polymer with a reduced volume, almost completely free of solvent and without degradation of the polymeric chains.  相似文献   
94.
We directly compare trip willingness to pay (WTP) values between dichotomous choice contingent valuation (DCCV) and discrete choice experiment (DCE) stated preference surveys of private party Grand Canyon whitewater boaters. The consistency of DCCV and DCE estimates is debated in the literature, and this study contributes to the body of work comparing the methods. Comparisons were made of mean WTP estimates for four hypothetical Colorado River flow-level scenarios. Boaters were found to most highly value mid-range flows, with very low and very high flows eliciting lower WTP estimates across both DCE and DCCV surveys. Mean WTP precision was estimated through simulation. No statistically significant differences were detected between the two methods at three of the four hypothetical flow levels.  相似文献   
95.
96.
Soil contamination by trace elements (TEs) is a problem of great concern since the industrial revolution. However, not all TEs are essentially toxic, and several micronutrients such as boron (B) play essential roles during plant development and, in this case, B acts in plants as a structural element. Soil B levels above 3.0 mg dm–3 may be toxic to many plants and the greatest input of B to the environment occurs through the anthropic way. An environmentally promising alternative is phytoremediation, in which contaminant‐tolerant plants are used to remove or stabilize TEs in soils. Therefore, this work has been carried out to aim C. mucunoides’ tolerance to increasing B concentrations and its potential as a phytoremediator. We found out that C. mucunoides tolerates B doses up to 480 mg dm?3, the B uptaken is transported at a 1:1 ratio between root and shoot, suggesting that C. mucunoides can be used as a phytostabilizer and phytoextractor due to its potential to be used in phytoremediation techniques because it can tolerate toxic concentrations of B.  相似文献   
97.
Abstract

This article reports the findings of a qualitative study with residents living in six deprived neighbourhoods in the UK and the front-line workers and local policymakers responsible for the renewal of these areas. The study was an attempt to raise awareness of local environmental concerns in the context of a national and local policy agenda, which has, until recently, largely overlooked the impacts of degraded environments on the lives and activities of the people who live in them. A key aim for the study was to raise people's concerns with local decision-makers and examine how far these might be addressed through the existing financial, administrative and legislative arrangements for neighbourhood renewal in the UK, namely Local Strategic Partnerships. The research was designed to provide practical lessons and policy recommendations for others wishing to raise the profile of environmental justice in the context of neighbourhood level regeneration projects, in both the UK and elsewhere in the ‘developed’ world.  相似文献   
98.
Waldman  P.  Lucas  F. S.  Varrault  G.  Moulin  L.  Wurtzer  S. 《Food and environmental virology》2020,12(2):118-129
Food and Environmental Virology - In urban rivers, many of which are used for drinking water production, viruses encounter a range of particulate, colloidal, and dissolved organic and inorganic...  相似文献   
99.
INTRODUCTION: The majority (67%) of hospitalized injuries among Alaska commercial fishermen are associated with deck machinery. This paper describes the "Prevention Through Design" process to mitigate one serious machinery entanglement hazard posed by a capstan deck winch. METHODS: After observing that the capstan winch provides no entanglement protection and the hydraulic controls are usually out of reach of the entangled person, NIOSH personnel met with fishermen and winch manufacturers to discuss various design solutions to mitigate these hazards. RESULTS: An emergency-stop ("e-stop") system was developed that incorporated a momentary contact button that when pushed, switches a safety-relay that de-energizes the solenoid of an electro-hydraulic valve stopping the rotating winch. The vessel owners that had the e-stop installed enthusiastically recommend it to other fishermen. NIOSH entered into a Proprietary Technology Licensing Agreement with a company to develop the system for commercial use. CONCLUSIONS: This is an example of a practical engineering control that effectively protects workers from a hazardous piece of equipment by preventing injuries due to entanglement. This solution could reduce these types of debilitating injuries and fatalities in this industry.  相似文献   
100.
Storm water runoff is increasingly assessed for fecal indicator organisms (e.g., Escherichia coli, E. coli) and its impact on contact recreation. Concurrently, use of autosamplers along with logistic, economic, technical, and personnel barriers is challenging conventional protocols for sample holding times and storage conditions in the field. A common holding time limit for E. coli is 8 h with a 10 °C storage temperature, but several research studies support longer hold time thresholds. The use of autosamplers to collect E. coli water samples has received little field research attention; thus, this study was implemented to compare refrigerated and unrefrigerated autosamplers and evaluate potential E. coli concentration differences due to field storage temperature (storms with holding times ≤24 h) and due to field storage time and temperature (storms >24 h). Data from 85 runoff events on four diverse watersheds showed that field storage times and temperatures had minor effects on mean and median E. coli concentrations. Graphs and error values did, however, indicate a weak tendency for higher concentrations in the refrigerated samplers, but it is unknown to what extent differing die-off and/or regrowth rates, heterogeneity in concentrations within samples, and laboratory analysis uncertainty contributed to the results. The minimal differences in measured E. coli concentrations cast doubt on the need for utilizing the rigid conventional protocols for field holding time and storage temperature. This is not to say that proper quality assurance and quality control is not important but to emphasize the need to consider the balance between data quality and practical constraints related to logistics, funding, travel time, and autosampler use in storm water studies.  相似文献   
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