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721.
As the societal benefits associated with transitioning to more sustainable, less fossil fuel-reliant energy systems are increasingly recognized by communities throughout the world, the potential of creating ‘green jobs’ within a ‘green economy’ is attracting much attention. Green energy clusters are increasingly promoted throughout the world as a strategy to simultaneously promote economic vitality and stimulate a sustainable energy transition. In spite of their emerging role in regional-scale sustainability planning efforts, such initiatives have not been considered within the sustainability transitions literature. This paper explores the development of one such regional sustainable energy cluster initiative in Central Massachusetts in Northeastern USA to consider the potential for such cluster initiatives to contribute to socio-technical transition in the energy system. Since 2008, a diverse set of stakeholders in Central Massachusetts, including politicians, universities, businesses, local citizens, and activists, have been working toward facilitating the emergence of an integrated cluster of activity focused on sustainable energy. Through interviews with key actors, participant observation, and document review, this research assesses the potential of this cluster initiative to contribute to a regional socio-technical transition. The empirical details of this case demonstrate that sustainable energy cluster initiatives can potentially accelerate change in entrenched energy regimes by promoting institutional thickness, generating regional ‘buzz’ around sustainable energy activities, and building trust between multiple and diverse stakeholders in the region. This research also contributes to emerging efforts to better ground socio-technical transitions in geographic space.  相似文献   
722.
Located in a relatively dry region and characterized by mainly sandy soils, the German Federal State of Brandenburg (surrounding the capital city of Berlin) is especially vulnerable to climate change impacts (e.g., summer droughts) and cascading effects on ecological systems (e.g., decreasing ground water tables, water stress, fire risk, productivity losses) with socioeconomic implications. Furthermore, a complex interplay of unemployment, rural exodus, and an aging population challenges this structurally weak region. We discuss adaptation measures that are either implemented or planned, as well as research into adaptation strategies to climate change for the sectors forestry, agriculture, and water management as well as in nature conservation in light of socioeconomic and ecological challenges and benefits. In doing so, we adopt a systemic view of Brandenburg where the sectors discussed are seen as subsystems embedded in a larger regional system. This at least partially holarchical approach enables the identification of conflicts between adaptation measures, but also of synergies among the sectors that pertain to successful adaptation to climate change. The insights gained ultimately highlight the need for cross-sectoral, adaptive management practices that jointly target a sustainable regional development.  相似文献   
723.
Investigations of place have often focused on either place meaning (utilizing interpretive designs) or place attachment (using quantitative measures). Rarely have researchers explored the association between place meaning and place attachment. Hence, this investigation was designed to explore how individuals' attachment to a natural environment is reflected in their depictions of why the resource is meaningful.  相似文献   
724.
End-of-life vehicles (ELV) have become a global concern as automobiles have become popular worldwide. An international workshop was held to gather data and to discuss 3R policies and ELV recycling systems, their background and present situation, outcomes of related policies and programs, the framework of recycling and waste management, and case studies on related topics in several countries and regions, as well as the essential points of the comparison. Legislative ELV recycling systems are established in the EU, Japan, Korea, and China, while in the US, ELV recycling is managed under existing laws on environmental protection. Since automobile shredding residue (ASR) has a high calorific value and ash content, and includes heavy metals as well as a mass of unclassified fine particles, recycling ASR is considered highly difficult. Countries with a legislative ELV system commonly set a target for recovery rates, with many aiming for more than 95 % recovery. In order to reach this target, higher efficiency in ASR recovery is needed, in addition to material recycling of collectable components and metals. Environmentally friendly design was considered necessary at the planning and manufacturing stages, and the development of recycling systems and techniques in line with these changes are required for sound ELV management.  相似文献   
725.
Petroleum coke or “petcoke” is a solid material created during petroleum refinement and is distributed via transfer facilities that may be located in densely populated areas. The health impacts from petcoke exposure to residents living in proximity to such facilities were evaluated for a petcoke transfer facilities located in Chicago, Illinois. Site-specific, margin of safety (MOS) and margin of exposure (MOE) analyses were conducted using estimated airborne and dermal exposures. The exposure assessment was based on a combined measurement and modeling program that included multiyear on-site air monitoring, air dispersion modeling, and analyses of soil and surfaces in residential areas adjacent to two petcoke transfer facilities located in industrial areas. Airborne particulate matter less than 10 microns (PM10) were used as a marker for petcoke. Based on daily fence line monitoring, the average daily PM10 concentration at the KCBX Terminals measured on-site was 32 μg/m3, with 89% of 24-hr average PM10 concentrations below 50 μg/m3 and 99% below 100 μg/m3. A dispersion model estimated that the emission sources at the KCBX Terminals produced peak PM10 levels attributed to the petcoke facility at the most highly impacted residence of 11 μg/m3 on an annual average basis and 54 μg/m3 on 24-hr average basis. Chemical indicators of petcoke in soil and surface samples collected from residential neighborhoods adjacent to the facilities were equivalent to levels in corresponding samples collected at reference locations elsewhere in Chicago, a finding that is consistent with limited potential for off-site exposure indicated by the fence line monitoring and air dispersion modeling. The MOE based upon dispersion model estimates ranged from 800 to 900 for potential inhalation, the primary route of concern for particulate matter. This indicates a low likelihood of adverse health effects in the surrounding community.?Implications: Handling of petroleum coke at bulk material transfer facilities has been identified as a concern for the public health of surrounding populations. The current assessment, based on measurements and modeling of two facilities located in a densely populated urban area, indicates that petcoke transport and accumulation in off-site locations is minimal. In addition, estimated human exposures, if any, are well below levels that could be anticipated to produce adverse health effects in the general population.  相似文献   
726.
727.
728.
Abstract

This paper introduces a predictive mechanism for elemental mercury (Hg0) oxidation on selective catalytic reduction (SCR) catalysts in coal-fired utility gas cleaning systems, given the ammonia (NH3)/nitric oxide (NO) ratio and concentrations of Hg0 and HCl at the monolith inlet, the monolith pitch and channel shape, and the SCR temperature and space velocity. A simple premise connects the established mechanism for catalytic NO reduction to the Hg0 oxidation behavior on SCRs: that hydrochloric acid (HCl) competes for surface sites with NH3 and that Hg0 contacts these chlorinated sites either from the gas phase or as a weakly adsorbed species. This mechanism explicitly accounts for the inhibition of Hg0 oxidation by NH3, so that the monolith sustains two chemically distinct regions. In the inlet region, strong NH3 adsorption minimizes the coverage of chlorinated surface sites, so NO reduction inhibits Hg0 oxidation. But once NH3 has been consumed, the Hg0 oxidation rate rapidly accelerates, even while the HCl concentration in the gas phase is uniform. Factors that shorten the length of the NO reduction region, such as smaller channel pitches and converting from square to circular channels, and factors that enhance surface chlorination, such as higher inlet HCl concentrations and lower NH3/NO ratios, promote Hg0 oxidation.

This mechanism accurately interprets the reported tendencies for greater extents of Hg0 oxidation on honeycomb monoliths with smaller channel pitches and hotter temperatures and the tendency for lower extents of Hg0 oxidation for hotter temperatures on plate monoliths. The mechanism also depicts the inhibition of Hg0 oxidation by NH3 for NH3/NO ratios from zero to 0.9. Perhaps most important for practical applications, the mechanism reproduces the reported extents of Hg0 oxidation on a single catalyst for four coals that generated HCl concentrations from 8 to 241 ppm, which covers the entire range encountered in the U.S. utility industry. Similar performance is also demonstrated for full-scale SCRs with diverse coal types and operating conditions.  相似文献   
729.
Abstract

The continuing increase in atmospheric carbon dioxide (CO2) makes it essential that climate sensitivity, the equilibrium change in global mean surface temperature that would result from a given radiative forcing, be quantified with known uncertainty. Present estimates are quite uncertain, 3 ± 1.5 K for doubling of CO2. Model studies examining climate response to forcing by greenhouse gases and aerosols exhibit large differences in sensitivities and imposed aerosol forcings that raise questions regarding claims of their having reproduced observed large-scale changes in surface temperature over the 20th century. Present uncertainty in forcing, caused largely by uncertainty in forcing by aerosols, precludes meaningful model evaluation by comparison with observed global temperature change or empirical determination of climate sensitivity. Uncertainty in aerosol forcing must be reduced at least three-fold for uncertaintyin climate sensitivity to be meaningfully reduced and bounded.  相似文献   
730.
A methodology is proposed to complement the subjective “value” of intelligence with an objective metric of “impact” of information on network models. This is a deterministic one-way sensitivity analysis similar to value of information used in inference diagrams. It would measure the impact of a piece of information on a network’s metric, in this case being used to answer intelligence analyst questions. This methodology suggests that the sensitivity of each link to existing analysis implies that the link has an impact on the analysis. The impact of these links can be measured quantitatively. In this paper, we explore data of tweets and apply the methodology to the links between twitter users and use the network measure of betweenness centrality to determine their quantitative impact on the overall network.  相似文献   
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