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961.
This paper proposes a mathematical model for life-cycle inventory analysis (LCI) of waste incineration in Switzerland. In order to model conventional and new incineration technologies adequately, fundamental aspects of the different technologies relevant for the LCI are discussed. The environmental impact of these technologies strongly depends on the assessment of the long-term emissions of the solid incineration residues and is therefore related to value based decisions about the time horizon considered. The article illustrates that the choice of the landfill model has a significant influence on the results of life-cycle assessment of waste incineration.  相似文献   
962.
The SWIM model is the first systems model in Australia that deals with integrated waste management systems. The main modelling approach adopted is simulation, which is based on both deterministic and stochastic models for collection systems.These models are described in this paper, after a number of modelling approaches are reviewed. An example of the application of the SWIM model is given, and planned extensions to the SWIM model are briefly outlined.  相似文献   
963.
Extraction of Crotalaria juncea (Sunn hemp) oil from its seeds is important to study because of its proven promising clean fuel characteristics. Soxhlet-based solvent extraction with some modification has been tried to extract the oil. In a fluid-solid mass transfer system, where, solids are present as packed bed, dynamic behavior of bed can be described in terms of concentration of solute in solids/solvent-time profile. Some of the well-known semi-empirical models of adsorption dynamics are modified and applied since leaching of oil is just the reverse of the phenomenon of adsorption in porous media. Modified Bohart-Adams model (non-linear), modified Bed Depth Service Time (BDST) (linear), and modified Thomas model (non-linear forms) are applied. It is found that these models fit to the experimental result reasonably well. Results suggest that higher bed height, with proper shape (annular) of the bed, having a higher solvent velocity will work best. Comparing the error values (SSE, SAE, and ARE) in the four cases, it is very clear that the modified BDST model is the most suitable. In the light of transient study it is established that the modified Soxhlet apparatus with cylindrical and annular beds, performs best while leaching Crotalaria juncea oil from their seeds.  相似文献   
964.
Abstract

In this paper, coming out of a broader research project on how the digital prototype can be effectively integrated in the product development process of the clothing industry, the authors investigate the relationship between Corporate Social Responsibility (CSR) and Collective Actions on Sustainability and the environmental impact of the new model of fast and accelerating fashion. Extensive research was contacted with personal interviews and analysed primary data shows how new technology solutions like Product Lifecycle Management (PLM), 3D visualisation or 3D prototyping can work with and across supply chain partners to reduce the environmental footprint of their processes. The final phase of the paper involves the conceptualisation of a new apparel product development model, encompassing various digital tools which aim at addressing fit problems, extending the useful life of clothes and reducing the environmental impact of clothing in use through design and services.  相似文献   
965.
Abstract

Re-distributed manufacturing (RDM), broadly described as manufacturing done at a smaller-scale and locally, could be beneficial to business and urban society through creating jobs, reducing the environmental impacts of production, and improving resilience to future disturbances. Consideration of RDM within a city-region requires the consideration of a wide range of issues – societal, technical, economic and environmental. This paper presents the results of a study into the potential for RDM to contribute to a sustainable, resilient city in the face of a range of expected future disturbances on the city and on manufacturing sectors. The study took an integrated assessment approach which incorporated the development of a conceptual framework; a ‘strawman’ causal loop diagram which was reviewed by participants in a workshop; and a stock and flow system dynamics model that represents our understanding about the structure and behaviour of urban manufacturing. Several key themes emerged: similarities between RDM and traditional manufacturing, availability of physical space for RDM to be done, achieving urban resilience through RDM by enabling responsiveness to disturbances, changes in environmental impacts from production, additions or losses in jobs, the competitiveness of local manufacturing, and skills and innovation for RDM technologies. Further work is recommended.  相似文献   
966.
This study investigated the thin-layer drying kinetics of salted silver jewfish in a hybrid solar drying system and under open sun. Ten drying models were compared with experimental data of salted silver jewfish drying. A new model was introduced, which is an offset linear logarithmic (offset modified Page model). The fit quality of the models was evaluated using the coefficient of determination (R2), root mean square error (RMSE), and sum of squared absolute error (SSAE). The result showed that Midilli et al. model and new model were comparable with two or three-term exponential drying models. This study also analyzed energy and exergy during solar drying of salted silver jewfish. Energy analysis throughout the solar drying process was estimated on the basis of the first law of thermodynamics, whereas exergy analysis during solar drying was determined on the basis of the second law of thermodynamics. At an average solar radiation of 540 W/m2 and a mass flow rate of 0.0778 kg/sec, the collector efficiency and drying system efficiency were about 41% and 23%, respectively. Specific energy consumption was 2.92 kWh/kg. Moreover, the exergy efficiency during solar drying process ranged from 17% to 44%, with an average value of 31%. The values of improvement potential varied between 106 and 436 W, with an average of 236 W.  相似文献   
967.
ABSTRACT

The important role that climate leaders and leadership play at different levels of the European Union (EU) multilevel governance system is exemplified. Initially, climate leader states set the pace with ambitious policy measures that were adopted largely on an ad hoc basis. Since the mid-1980s, the EU has developed a multilevel climate governance system that has facilitated leadership and lesson-drawing at all governance levels including the local level. The EU has become a global climate policy leader by example although it had been set up as a ‘leaderless Europe’. The resulting ‘leadership without leader’ paradox cannot be sufficiently explained merely by reference to top-level EU climate policies. Local-level climate innovations and lesson-drawing have increasingly been encouraged by the EU’s multilevel climate governance system which has become more polycentric. The recognition of economic co-benefits of climate policy measures has helped to further the EU’s climate leadership role.  相似文献   
968.
长江靖江段刀鲚捕捞量的时间变化及相关环境因子分析   总被引:3,自引:0,他引:3  
江苏靖江段位于长江近口段,是长江刀鲚渔汛最集中的水域。调查了靖江段2008、2009、2012~2015年6个渔汛期的捕捞数据,采用广义可加模型(GAM模型)分析了刀鲚捕捞量与靖江段表层水温、潮差、气压、降水量、浑浊度、CODMn等环境因子之间的相关性。调查显示,靖江段每年发放刀鲚专项渔业捕捞证84~95本,平均年作业天数28~43 d,2012~2015年的作业天数比2008~2009年明显下降。6个渔汛期刀鲚的年捕捞量变幅为3.71~17.38万尾和3.61~18.26 t,除2013年外,年捕捞量总体上仍呈下降趋势。采用GAM模型对10艘持证渔船的刀鲚日捕捞量与环境因子之间的相关性分析显示,日捕捞量随水温的升高而递增,汛期78.8%的产量在15~23.2℃水温范围获得。而当水温低于10℃时,空网率上升,仅获得5.7%的汛期产量。表明当水温不足10℃时,刀鲚可暂时停止其生殖洄游过程。分析还显示,69.1%的汛期产量在2.0 m以上的大潮差期获得,表明潮汐亦是影响刀鲚日捕捞量的重要因子。低浊度及气压、降水量、CODMn等对刀鲚的日捕捞量无显著性影响,但当浊度大于100 NTU时,日捕捞量迅速降低。可见,水温、潮差和高浑浊度是影响长江靖江段汛期刀鲚捕捞量的关键环境因子。  相似文献   
969.
欠发达资源富集山区的生态文明发展模式与对策建议   总被引:1,自引:0,他引:1  
结合国内外区域经济发展经验和黔东南实地调研情况,分析了欠发达资源富集区和山区资源开发的一些基本特征,指出了黔东南山区的生态价值和经济价值,认为开展生态文明建设是黔东南这样欠发地区实现经济与生态双赢的理想选择。黔东南州是我国经济欠发达、资源富集、生态优质、少数民族文化独特的典型山区,具有原形的自然生态、原始的民族文化、原貌的历史遗存,其生态价值具有十分明显的比较优势。生态文明是指人与自然和谐共荣的文化价值取向、生态系统良性发展下的可持续生产、满足人类自身需要又不损害自然系统的可持续消费的一种社会形态。提出了黔东南发展生态农业、生态工业循环经济、生态旅游、生态城镇和政府绿色管理等具体发展模式,最后从宣传教育、科技创新、特色经济、生态产业链和低碳经济等提出了若干对策建议。  相似文献   
970.
220 kV高压输电线电磁辐射水平及防护距离预测   总被引:1,自引:0,他引:1  
依据<500 kV超高压送变电工程电磁辐射环境影响评价技术规范>(HJ/T 24-1998)中的预测模式对监测点周围地面1.5 m处工频电场进行了验证性监测,表明实际测定结果与理论计算结果基本吻合.通过对220 kV双回同相、双回逆相和单回线路下地面1.5 m、4.5 m、和7.5 m处工频电场变化趋势分析,预测了220 kV高压输电线产生的电磁辐射水平,以及不同房屋结构的防护距离.提出了220 kV高压输电线电磁辐射的防护措施.  相似文献   
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