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991.
Abstract: Economic growth‐the increase in production and consumption of goods and services‐must be considered within its biophysical context. Economic growth is fueled by biophysical inputs and its outputs degrade ecological processes, such as the global climate system. Economic growth is currently the principal cause of increased climate change, and climate change is a primary mechanism of biodiversity loss. Therefore, economic growth is a prime catalyst of biodiversity loss. Because people desire economic growth for dissimilar reasons‐some for the increased accumulation of wealth, others for basic needs‐how we limit economic growth becomes an ethical problem. Principles of distributive justice can help construct an international climate‐change regime based on principles of equity. An equity‐based framework that caps economic growth in the most polluting economies will lessen human impact on biodiversity. When coupled with a cap‐and‐trade mechanism, the framework can also provide a powerful tool for redistribution of wealth. Such an equity‐based framework promises to be more inclusive and therefore more effective because it accounts for the disparate developmental conditions of the global north and south.  相似文献   
992.
于2017年1月采集镇江市典型产业园区7个不同点位的青菜及青菜田土壤样品进行重金属含量分析,结果表明,园区青菜中Cr、Cu、Zn元素均值小于食品卫生标准限值,Ni、Cd和Pb元素的均值介于食品卫生标准限值的临界;青菜中Ni、Cd、Pb 3种重金属处于轻度污染状态,Cr、Cu和Zn 3种重金属为无污染状态;青菜田土壤中重金属含量仅Cr和Cd在个别点超过《土壤环境质量农用地土壤污染风险管控标准》(GB 15618—2018)标准限值,其余各点位6种重金属元素均低于标准限值。  相似文献   
993.
Purpose. In ergonomics and human factors investigations, pulling force (PF) estimation has usually been achieved using various types of biomechanical models, and independent approximation of PF was done with the help of upper extremity joints. Recently, multiple regression methods have gained importance for task-relevant inputs in predicting PF. Artificial neural networks (ANNs) also play a vital role in fitting the data; however, their use in work-related biomechanics and ergonomics is inadequate. Therefore, the current research aimed to accomplish comparative investigation of ANN and regression models by assessing their capacity to predict PF values. Methods. Multipositional PF data were acquired from 200 subjects at three different handle heights and body locations. ANN and regression models were formed using a random sample of three subsets (75% training, 15% selection, 10% validation) for proving the outcomes. Results. The comparison of ANN and regression models shows that the predictions of ANN models had a profoundly explained variance and lower root mean square difference values for the PF data at three handle heights. Conclusions. These outcomes advise that ANNs offer a precise and robust substitute for regression methods, and should be considered a useful method in biomechanics and ergonomics task assessments.  相似文献   
994.
邹高龙 《环境工程学报》2014,8(6):2467-2472
针对城市生活污水,研究了两点进水倒置A2/O-MBR(平板膜)系统(以下简称系统)对COD、NH+4-N、TN、TP、出水SS影响。结果表明,该系统对COD、NH+4-N具有较高的去除率,出水符合GB18918-2002中一级A标准;当混合液回流比为200%时,系统出水TN浓度小于15 mg/L;正常排泥后,系统对TP的去除率达83%左右;平板膜破损会导致出水SS、COD会受到影响。膜对COD、TP、SS有直接截留作用,由于系统出水几乎没有固体损失,可以精确控制污泥龄,有利于世代周期较长的硝化菌和反硝化菌生长;系统中的污泥浓度可以提高至15 000 mg/L,此时,即使进水量提高0.5倍,出水水质仍保持良好。  相似文献   
995.
In situ aeration by means of the Airflow technology was proposed for landfill conditioning before landfill mining in the framework of a reclamation project in Northern Italy. A 1-year aeration project was carried out on part of the landfill with the objective of evaluating the effectiveness of the Airflow technology for landfill aerobization, the evolution of waste biological stability during aeration and the effects on leachate and biogas quality and emissions.The main outcomes of the 1-year aeration project are presented in the paper.The beneficial effect of the aeration on waste biological stability was clear (63% reduction of the respiration index); however, the effectiveness of aeration on the lower part of the landfill is questionable, due to the limited potential for air migration into the leachate saturated layers.During the 1-year in situ aeration project approx. 275 MgC were discharged from the landfill body with the extracted gas, corresponding to 4.6 gC/kgDM. However, due to the presence of anaerobic niches in the aerated landfill, approx. 46% of this amount was extracted as CH4, which is higher than reported in other aeration projects. The O2 conversion quota was lower than reported in other similar projects, mainly due to the higher air flow rates applied.The results obtained enabled valuable recommendations to be made for the subsequent application of the Airflow technology to the whole landfill.  相似文献   
996.
In industrialized countries, large amounts of mineral wastes are produced. They are re-used in various ways, particularly in road and earth constructions, substituting primary resources such as gravel. However, they may also contain pollutants, such as heavy metals, which may be leached to the groundwater. The toxic impacts of these emissions are so far often neglected within Life Cycle Assessments (LCA) of products or waste treatment services and thus, potentially large environmental impacts are currently missed. This study aims at closing this gap by assessing the ecotoxic impacts of heavy metal leaching from industrial mineral wastes in road and earth constructions. The flows of metals such as Sb, As, Pb, Cd, Cr, Cu, Mo, Ni, V and Zn originating from three typical constructions to the environment are quantified, their fate in the environment is assessed and potential ecotoxic effects evaluated. For our reference country, Germany, the industrial wastes that are applied as Granular Secondary Construction Material (GSCM) carry more than 45,000 t of diverse heavy metals per year. Depending on the material quality and construction type applied, up to 150 t of heavy metals may leach to the environment within the first 100 years after construction. Heavy metal retardation in subsoil can potentially reduce the fate to groundwater by up to 100%. One major challenge of integrating leaching from constructions into macro-scale LCA frameworks is the high variability in micro-scale technical and geographical factors, such as material qualities, construction types and soil types. In our work, we consider a broad range of parameter values in the modeling of leaching and fate. This allows distinguishing between the impacts of various road constructions, as well as sites with different soil properties. The findings of this study promote the quantitative consideration of environmental impacts of long-term leaching in Life Cycle Assessment, complementing site-specific risk assessment, for the design of waste management strategies, particularly in the construction sector.  相似文献   
997.
ABSTRACT

The large share of carbon emitted by energy-intensive industries in the extraction and processing of basic materials must be limited to decarbonise society and the economy. Ways in which the state can govern industrial decarbonisation and contributes to green state theory are explored by addressing a largely ignored issue: the green state’s industrial relations and its role in industrial governance. With insights from a Swedish case study, the tension between the state’s economic imperative and ecological concerns in greening industry are shown to persist. However, as the energy-intensive industry’s previously privileged position in the economy is weakening, industry is opened to decarbonisation strategies. While the case exposes a number of governance challenges, it also suggests potential areas where the state can pursue decarbonisation in energy-intensive industry and points the way to an active role of the green state in governing industrial decarbonisation and greening industry.  相似文献   
998.
This study involves a meta-analytical review of several articles, using the closest assumptions for the independent variable (renewable energy consumption), to determine the relationship with its environmental impacts. Furthermore, Sustainable Development Goal (SDG) in 2015 pays attention to related problems in both developing and developed countries. The effects of carbon emissions, natural resources, renewable energy consumption, and non-renewable energy on the environment are also reviewed. Following the separation of studies, the closest assumption was observed for the independent variable (energy source applications) of renewable energy. The meta-analysis was obtained using OpenMEE and JASP, and the results show the observed outcome, which was expressed in percentage. Based on the analysis, the Renewable Energy model has a value of 0.15, with the largest forest plots of 0.73, 0.69, and 0.80, recorded for studies 13, 19, and 23, respectively, while the least forest plots were recorded for studies 6, 11, 12, 15, 20, 22, 24, 25, 26, and 28. Therefore, renewable energy consumption, specifically in the mining industry, has the capacity to influence global warming. The respective industry has a unique influence on the processes that require renewable energy, for instance, the coal mining industry produces a smaller forest plot value, compared to oil and gas, or other mineral industries.  相似文献   
999.
In the electricity sector, innovation in large-scale storage is anticipated to reduce costs and improve performance. The effect on greenhouse gas emissions of lower storage costs depends on the interactions between storage and the entire grid. The literature has disagreed on the role of storage in reducing emissions. In this paper we present a stylized model, which suggests that the effect of storage costs on emissions depends on the supply responsiveness of both fossil and renewable generators. Under common conditions in the United States, lower storage costs are more likely to reduce emissions when wind investment responds to equilibrium electricity prices and when solar investment does not. Simulations of a computational model of grid investment and operation confirm these intuitions. Moreover, because of its effect on coal and natural gas–fired supply responsiveness, introducing a carbon dioxide emissions price may increase the likelihood that lower storage costs reduce emissions.  相似文献   
1000.
产业生态学是最近兴起的一门很有前途的学问,它继承和发展了自然生态系统的理论,并运用它来指导面临危境的工业生产活动。它与我国目前提倡的生态农业有相似的地方,也有很大的不同。本文结合对中西方对产业生态学思想和实践的对比,分析了各自的优势,指出了不足  相似文献   
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