铬渣对地下水、土壤、蔬菜污染机制的研究

本文对沈阳市化工石油厂（现为石油化工二厂），在６０年代产生废铬渣６０００余吨．由于铬渣堆放不合理，经过风吹雨淋造成了周围环境污染，导致了沈海菜田的地下水．土壤、蔬菜受到严重污染．通过专项调研，全面剖析了铬渣中的六价铬对地下水、土壤、蔬菜的污染规律．     

Adjusting the economy to the new energy realities of the second half of the age of oil

Our research indicates that, due to the depletion of conventional, and hence cheap, crude oil supplies (i.e. peak oil), increasing the supply of oil in the future would require exploiting lower quality resources (i.e. expensive), and thus will most likely occur only at high prices. This situation creates a system of feedbacks where economic growth, which requires more oil, would require high oil prices that will undermine that economic growth. We conclude that the economic growth of the past 40 years is unlikely to continue unless there is some remarkable change in how we manage our economy.     

Scientific research, stakeholders, and policy: continuing dialogue during research on radionuclides on Amchitka Island, Alaska

It is increasingly clear that a wide range of stakeholders should be included in the problem formulation phase of research aimed at solving environmental problems; indeed the inclusion of stakeholders at this stage has been formalized as an integral part of ecological risk assessment. In this paper, we advocate the additional inclusion of stakeholders in the refinement of research methods and protocols and in the execution of the research, rather than just at the final communication and reporting phase. We use a large study of potential radionuclide levels in marine biota around Amchitka Island as a case study. Amchitka Island, in the Aleutian Island Chain of Alaska, was the site of three underground nuclear tests (1965-1971). The overall objective of the biological component of the study was to collect a range of marine biota for radionuclide analysis that could provide data for assessing current food safety and provide a baseline for developing a plan to monitor human and ecosystem health in perpetuity. Stakeholders, including regulators (State of Alaska), resource trustees (US Fish and Wildlife Service, State of Alaska), representatives of the Aleut and Pribilof Island communities, the Department of Energy (DOE), and others, were essential for plan development. While these stakeholders were included in the initial problem formulation and approved science plan, we also included them in the refinement of protocols, selection of bioindicators, selection of a reference site, choice of methods of collection, and in the execution of the study itself. Meetings with stakeholders resulted in adding (or deleting) bioindicator species and tissues, prioritizing target species, refining sampling methods, and recruiting collection personnel. Some species were added because they were important subsistence foods for the Aleuts, and others were added because they were ecological equivalents to replace species deleted because of low population numbers. Two major refinements that changed the research thrust were (1) the inclusion of Aleut hunters and fishers on the biological expedition itself to ensure that subsistence foods and methods were represented, and (2) the addition of a fisheries biologist on a NOAA research trawler to allow sampling of commercial fishes. Although the original research design called for the collection of biota by Aleut subsistence fishermen, and by a commercial fishing boat, the research was modified with continued stakeholder input to actually include Aleuts and a fisheries biologist on the expeditions to ensure their representation. The inclusion of stakeholders during the development of protocols and the research itself improved the overall quality of the investigation, while making it more relevant to the interested and affected parties. Final responsibility for the design and execution of the research and radionuclide analysis rested with the researchers, but the process of stakeholder inclusion made the research more valuable as a source of credible information and for public policy decisions.     

What makes institutional crafting successful? Applying the SES to case studies from India and the greater Mekong Region

Using two very different empirical settings, this paper emphasizes the required conditions for the successful crafting of sustainable institutions. In the first setting, different farmer groups in Cambodia and Vietnam try to establish a collective approach for small-scale community-based aquaculture and fail. In the second setting, the collective initiatives of urban women in India are analysed. The Indian women succeed in their objective of a fuel transition from firewood to gas cookers using a cooperative approach. Ostrom's variables identified in the “Multitier Framework for Analyzing Social–Ecological Systems (SES)” (Ostrom, 2007) are applied to local collective action initiatives in both settings to understand which factors make some of the groups succeed in their objectives and others fail. This research highlights the complexity as well as the uniqueness of different SESs. At the same time, the paper contributes to demonstrating the usability of the SES and certain variables to estimate the likelihood of success of self-organisation and crafting of rules. It highlights the relevance of certain conceptual variables for sustainable or unsustainable outcomes for different cases.     

Energy input during friction stir spot welding

Friction stir spot welding is performed on thin plates of an aluminum alloy. This paper presents the results on how the number of tool rotations affects the quality of the resulting spot weld. Different combinations of rotation rate and dwell time are investigated. A linear relationship was found to exist between the number of tool rotations completed during the spot weld and the resulting tensile shear strength. Spot welds that only completed 10 rotations were 177% stronger than those created at 50 tool rotations. The energy generated during the welding operation was quantified and also found to have a linear relationship with tensile shear strength. A modified open-loop position control system is proposed that monitors and limits the energy generated during friction stir spot welding by adjusting the dwell time.     

荷兰长期能效协议和能效标杆合约及启示

提高能效是减排的重要途径,荷兰长期能效协议和能效标杆合约在这方面取得了很大成效,其成功经验值得研究和学习。本文首先系统介绍了荷兰长期能效协议和能效标杆合约的构建、实施及监督过程,分析了其取得的成效和存在的不足。然后描述了自愿协议式方法在中国的应用情况和我国面临的节能减排压力。最后总结出长期能效协议和能效标杆合约对我国应用和推广自愿协议式方法的启示。     

Environmental assessment of different management options for individual waste fractions by means of life-cycle assessment modelling

Several alternatives exist for handling of individual waste fractions, including recycling, incineration and landfilling. From an environmental point of view, the latter is commonly considered as the least desirable option. Many studies based on life-cycle assessment (LCA) highlight the environmental benefits offered by incineration and especially by recycling. However, the landfilling option is often approached unjustly in these studies, maybe disregarding the remarkable technological improvements that landfills have undergone in the last decades in many parts of the world.This study, by means of LCA-modelling, aims at comparing the environmental performance of three major management options (landfilling, recycling and incineration or composting) for a number of individual waste fractions. The landfilling option is here approached comprehensively, accounting for all technical and environmental factors involved, including energy generation from landfill gas and storage of biogenic carbon. Leachate and gas emissions associated to each individual waste fraction have been estimated by means of a mathematical modelling. This approach towards landfilling emissions allows for a more precise quantification of the landfill impacts when comparing management options for selected waste fractions.Results from the life-cycle impact assessment (LCIA) show that the environmental performance estimated for landfilling with energy recovery of the fractions “organics” and “recyclable paper” is comparable with composting (for “organics”) and incineration (for “recyclable paper”). This however requires high degree of control over gas and leachate emissions, high gas collection efficiency and extensive gas utilization at the landfill. For the other waste fractions, recycling and incineration are favourable, although specific emissions of a variety of toxic compounds (VOCs, PAHs, NO_x, heavy metals, etc.) may significantly worsen their environmental performance.     

Environmental impact of meat meal fertilizer vs. chemical fertilizer

Animal by-products (ABP) are rich in nutrients and energy. This LCA study assessed and compared the environmental impact of using meat meal as fertilizer with that of using chemical fertilizer. In one system the nutrient content of ABP Category 2 was recovered and used as a meat meal fertilizer on arable land, replacing chemical fertilizers. In the other system a chemical fertilizer was used and the energy content of the ABP material recovered. The functional unit consisted of one kg of harvested spring wheat and treatment of 0.59 kg of ABP Category 2. The system for nutrient recovery and chemical fertilizer replacement had lower emissions of greenhouse gases and acidification than the energy recovery system, but had higher total use of energy and eutrophying emissions. Overall, the results of the study greatly depended on the fuels replaced.     

Assessing energy efficiencies and greenhouse gas emissions under bioethanol-oriented paddy rice production in northern Japan

To establish energetically and environmentally viable paddy rice-based bioethanol production systems in northern Japan, it is important to implement appropriately selected agronomic practice options during the rice cultivation step. In this context, effects of rice variety (conventional vs. high-yielding) and rice straw management (return to vs. removal from the paddy field) on energy inputs from fuels and consumption of materials, greenhouse gas emissions (fuel and material consumption-derived CO(2) emissions as well as paddy soil CH(4) and N(2)O emissions) and ethanol yields were assessed. The estimated ethanol yield from the high-yielding rice variety, "Kita-aoba" was 2.94 kL ha(-1), a 32% increase from the conventional rice variety, "Kirara 397". Under conventional rice production in northern Japan (conventional rice variety and straw returned to the paddy), raising seedlings, mechanical field operations, transportation of harvested unhulled brown rice and consumption of materials (seeds, fertilizers, biocides and agricultural machinery) amounted to 28.5 GJ ha(-1) in energy inputs. The total energy input was increased by 14% by using the high-yielding variety and straw removal, owing to increased requirements for fuels in harvesting and transporting harvested rice as well as in collecting, loading and transporting rice straw. In terms of energy efficiency, the variation among rice variety and straw management scenarios regarding rice varieties and rice straw management was small (28.5-32.6 GJ ha(-1) or 10.1-14.0 MJ L(-1)). Meanwhile, CO(2)-equivalent greenhouse gas emissions varied considerably from scenario to scenario, as straw management had significant impacts on CH(4) emissions from paddy soils. When rice straw was incorporated into the soil, total CO(2)-equivalent greenhouse gas emissions for "Kirara 397" and "Kita-aoba" were 25.5 and 28.2 Mg CO(2) ha(-1), respectively; however, these emissions were reduced notably for the two varieties when rice straw was removed from the paddy fields in an effort to mitigate CH(4) emissions. Thus, rice straw removal avers itself a key practice with respect to lessening the impacts of greenhouse gas emissions in paddy rice-based ethanol production systems in northern Japan. More crucially, the rice straw removed is available for ethanol production and generation of heat energy with a biomass boiler, all elements required for biomass-to-ethanol transformation steps including saccharification, fermentation and distillation. This indicates opportunities for further improvement in energy efficiency and reductions in greenhouse gas emissions under whole rice plant-based bioethanol production systems.     

超细水雾抑制酒精火有效性实验研究

为了研究超细水雾对酒精火的抑制效果,通过搭建超细水雾抑制受限空间酒清火燃烧的小尺寸实验平台,利用基于质量损失速率的热释放速率计算方法,研究超细水雾与酒精火焰相互作用时,酒精火火焰的变化规律及酒精火的热释放速率,与此同时,采用高速摄像仪对火焰进行拍摄,利用Matlab图像处理程序对采集的火焰图片剖面进行处理.研究发现:施...