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301.
Green chemistry     
A grand challenge facing government, industry, and academia in the relationship of our technological society to the environment is reinventing the use of materials. To address this challenge, collaboration from an interdisciplinary group of stakeholders will be necessary. Traditionally, the approach to risk management of materials and chemicals has been through inerventions intended to reduce exposure to materials that are hazardous to health and the environment. In 1990, the Pollution Prevention Act encouraged a new tact-elimination of hazards at the source. An emerging approach to this grand challenge seeks to embed the diverse set of environmental perspectives and interests in the everyday practice of the people most responsible for using and creating new materials—chemists. The approach, which has come to be known as Green Chemistry, intends to eliminate intrinsic hazard itself, rather than focusing on reducing risk by minimizing exposure. This chapter addresses the representation of downstream environmental stakeholder interests in the upstream everyday practice that is reinventing chemistry and its material inputs, products, and waste as described in the “12 Principles of Green Chemistry”.  相似文献   
302.
An assessment of potential biomass resources in Nigeria for the production of methane and power generation is presented in this paper. Nigeria, as an underdeveloped and populous country, needs an uninterrupted source of energy. The country's energy problems have crippled large sectors of the economy. The percentage of people connected to the national grid is 40%. These 40% experience electricity supply failure on average 10–12 hours daily. Energy generation from municipal solid waste (MSW) is an effective MSW management strategy. Yearly waste generation has increased from 6,471 gigagrams (Gg) in 1959 to 26,600 Gg in 2015. This amount is projected to reach 36,250 Gg per year by 2030. Methane emission for 2015 was 491 Gg, and it is projected to reach 669 Gg in 2030. These values translate to 3.48 × 109 kilowatt hours (kWh) of electricity for 2015, with a projected 4.74 × 109 kWh by 2030. The revenue to be derived from the electricity that is generated could have been US$365.04 × 106 for 2015, and it is estimated that it will reach US$473.82 × 106 by 2030. It was found that methane emissions from MSW increased with time, and capturing this gas for energy production will lead to a sustainable waste management.  相似文献   
303.
单室微生物燃料电池产电与脱氮除磷的研究   总被引:2,自引:1,他引:1  
实验针对空气阴极型单室微生物燃料电池(Microbial Fuel Cell,MFC),研究其产电性能及对实验室模拟废水中有机物、氮和磷元素的去除效果.结果表明,在外电阻为1000Ω的情况下,该电池最大输出电压可达371 m V,最大输出功率密度可达301.6 m W·m~(-2),最大电流密度可达2.4 A·m~(-2),内阻为200Ω.当入水氨氮浓度为4 mmol·L~(-1)时,该电池的产电效果最好,对污染物的去除效果也较好.研究还发现,电池最佳运行周期为72 h,阳极室出水最佳曝气时间为6 h,阳极室出水COD、TN和TP的降解率分别为93.3%、19.7%和44.8%.将阳极液曝气处理后,相对于阳极室入水其TN和TP的总去除率分别可达79.6%和95.2%.另外,通过扫描电镜观察到MFC的阳极液中大多为球形菌,阴极电极表面有针状的结晶形成,经能谱测试为鸟粪石结晶.  相似文献   
304.
The purpose of this research is to gain an empirical understanding of airline passengers’ green switching intentions. A conceptual research model is used as a framework to examine the relationships among the experiential quality dimensions, green perceived value, green corporate image, green experiential satisfaction, green corporate reputation, green experiential loyalty and green switching intentions for the airline industry. The data used in this paper were based on a sample of 615 passengers who experienced the eco-friendly services of China Airlines, indicating that the proposed model fitted the data. The study's result will assist airline management to develop and implement market-orientated service strategies to increase the experiential quality dimensions, green perceived value, green corporate image, green experiential satisfaction, green corporate reputation and green experiential loyalty in order to decrease passengers’ green switching intentions.  相似文献   
305.
Land-use planning is an important determinant for green space policy in cities. It defines land covers and hence the structure and function of urban ecosystems and the benefits these provide to humans, such as air purification, urban cooling, runoff mitigation, and recreation. The ecosystem service approach has helped to attract policy attention to these benefits but the concept remains poorly implemented in urban policy and governance. To address this gap, we advance a framework to bridge ecosystem services into policy processes through Multi-Criteria Decision Analysis (MCDA) as decision support tool. The paper is organized in three main parts. First, we conduct a systematic literature review to assess state-of-the-art knowledge on ecosystem service assessments through MCDA. Next, we build on insights from the literature review to develop the ‘ecosystem services policy-cycle’, a conceptual framework that merges the ‘ecosystem service cascade’ and ‘policy cycle’ models to reinforce the link between ecosystem service assessments and practical applications in urban policy and governance. Next, we illustrate the applicability of the proposed framework along an example about conflicting interests on land use and green space planning following the closure of the Airport Tempelhof in Berlin, Germany. Our results highlight the scope of MCDA as a decision support tool for integrating ecosystem service assessments in green space governance. We discuss advantages and disadvantages of different methodological choices in the use of MCDA in ecosystem service assessments and note that a key strength of this tool in informing green space policies lies in its capacity to accommodate conflicting stakeholder perspectives and to address trade-offs between ecological, social and economic values.  相似文献   
306.
In many European cities, urban gardens are seen as increasingly important components of urban green space networks. We adopt an ecosystem services framework to assess contributions of urban gardens to the quality of of their users. First, we identify and characterize ecosystem services provided by urban gardens. Secondly, we assess the demographic and socioeconomic profile of its beneficiaries and the relative importance they attribute to different ecosystem services. Next we discuss the relevance of our results in relation to critical policy challenges, such as the promotion of societal cohesion and healthy lifestyles. Data were collected through 44 semi-structured interviews and a survey among 201 users of 27 urban gardens in Barcelona, Spain, as well as from consultation meetings with local planners. We identified 20 ecosystem services, ranging from food production over pollination to social cohesion and environmental learning. Among them, cultural ecosystem services (non-material benefits people derive from their interaction with nature) ​ stand out as the most widely perceived and as the most highly valued. The main beneficiaries of ecosystem services from urban gardens are elder, low-middle income, and migrant people. Our results about the societal importance of urban gardens ​were deemed highly relevant by the interviewed green space planners in Barcelona, who noted that our data can provide basis to support or expand existing gardening programs in the city. Our research further suggests that ecosystem services from urban gardens can play an important role in addressing several urban policy challenges in cities, such as promoting stewardship of urban ecosystems, providing opportunities for recreation and healthy lifestyles, and promoting social cohesion. We conclude that urban gardens and associated ecosystem services can play an important ​ in urban policies aimed at enhancing quality of life in cities, particularly if access to their benefits is expanded to larger segments of the population.  相似文献   
307.
Complex relationships exist between programs to reduce carbon dioxide (CO2) from the electricity sector and programs to promote renewable electricity generation. Simulation modeling of three scenarios in the UK electricity sector are used to identify potential interactions between these programs. A strict CO2 cap can result in a renewable electricity requirement being easily met. Conversely, the renewables quota could be required under low natural gas prices to keep electricity suppliers from switching from coal to gas. Similarly, CO2 trading can reduce renewables deployment levels because purchased CO2 allowances replace renewables. Therefore, both programs are required to ensure CO2 and renewables goals. The planning implications for administrative procedures and renewables subsidies are also discussed.  相似文献   
308.
The main purpose of this study was to develop a set of measures for evaluating the performance of the automobile green supply chain. This study reviewed various literatures on green supply chain performance measurement, environmental management, traditional supply chain performance measurement, and automobile supply chain management. In order to comprehensively and effectively establish the relevant measures, a suitable framework which considered the automobile green supply chain as a two-in-one chain was adopted. This two-in-one chain comprised a forward and backward chain for the automobile industry. Consequently, 10 measures with 49 metrics and 6 measures with 23 metrics were identified and developed for the forward and backward chains, respectively. Sequel to the development of these measures, a survey was conducted using a four-page questionnaire distributed to experts (including academics and practitioners) to establish their importance and applicability. The findings of this study suggested that the importance and applicability of all the developed measures have been substantiated. For the forward chain, the most crucial measure was customer perspective while the most applicable one was traditional supply chain cost. The reverse chain measures were topped by management commitment in terms of both importance and applicability. This study contributed to the advancement of knowledge by pioneering the development of a set of holistic measures for evaluating the performance of the automobile green supply chain. The study was wrapped up with the proposition of directions for further studies.  相似文献   
309.
Nineteen persons “hypersensitive” to electricity and 20 nonafflicted persons were studied for 1 ½ years. The most discernible hypersensitivity symptoms were pricking sensations and redness in the face, but these symptoms were present in only half of the afflicted. Other symptoms were similar to symptoms experienced during office work and this study does not support the idea that electrosensitivity is one single syndrome. The “hypersensitive” persons improved significantly, mainly on neuropsychiatric symptoms, but the skin problems sustained— as did the belief about their cause. The afflicted persons used less conventional medication than the group of the nonafflicted, which suggests a general tendency for attribution to environmental factors.  相似文献   
310.

Social scientists have described Japan's urban anti-pollution protests in the 1960s as a national phenomenon. However, in Kitakyushu, Japan's most polluted industrial city at that time, no distinct citizens' movement developed. Because local politics and economics were so dominated by large industry, its citizens were reluctant to directly challenge these industries. Instead, local women's groups studied local pollution problems and presented their general findings to the public. These activities raised public awareness and resulted in increased support for local leftist politicians because leftist administrations had succeeded in cutting pollution in their cities. Kitakyushu's conservative mayor and local industry both became concerned that leftists would win the next local elections if pollution was not reduced. Thus the municipal government utilised scientific pollution data and prepared individualised pollution reduction recommendations in sulphur oxide pollution control agreements, which were accepted and complied with by all local industries. The result was a significant reduction in air pollution without the need for active intervention from Kitakyushu's citizenry. Cientificos sociales han descrito las protestas anti-polución urbana de Japon en los años 60 como un fenómeno nacional. Sinembargo, en Kitakyushu, ciudad industrial japonesa más polucionada en ese tiempo, no se desarrollóningún movimiento ciudadano evidente. Debido a que las políticas locales y económicas eran dominadas por la gran industria, sus ciudadanos no estaban dispuestos a retar directamente estas industrias. En lugar de eso, grupos locales de mujeres estudiaron problemas locales de polución y presentaron sus resultados al público. Estas actividades despertaron conciencia pública y resultaron en el incremento del apoyo para políticos izquierdistas locales debido a que las administraciones izquierdistas habían triunfado en la reducción de la polución en sus ciudades. El alcalde conservador y la industria local de Kitakyushu empezaron a preocuparse que los izquierdistas ganarían las próximas elecciones locales si la polución no era reducida. Asíque, el Gobierno Municipal utilizó información científica sobre polución y preparó recomendaciones de reducción de polución individualizada en acuerdos de control de polución en oxído sulfurico, los cuales fueron aceptados y obedecidos por todas las industrias locales. El resultado fue una significativa reducción en la polución del aire sin la necesidad de la intervención activa de parte de la ciudadania de Kitakyushu.  相似文献   
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