燃煤小锅炉替代方案论证及效益分析——以济南市为例

通过对燃煤小锅炉各可行替代方案的分析,从环境标准要求、政策要求、环境效益、经济效益和节能等方面,论证了燃煤小锅炉替代的必要性与可行性。结果表明天然气、电和生物质锅炉及集中供热均具有良好的环境效益和经济可行性,可作为燃煤小锅炉的替代方案。济南市通过实施燃煤小锅炉替代,预计将减少烟尘排放量182.61 t/a,减少SO_2排放量898.8 t/a,减少NO_x排放量2 710.7 t/a,与淘汰前燃煤小锅炉排放量相比,分别降低了87.7%、82.9%和86.2%,年可节约折标煤140 903.27 t。节能减排效益显著。可为同类燃煤小锅炉替代工程提供参考。     

Rebuilding and strengthening health systems and providing basic health services in fragile states

The international community has compelling humanitarian, political, security and economic reasons to engage in rebuilding and strengthening health systems in fragile states. Improvements in health services and systems help to strengthen civil society and to restore legitimacy to governments. Effective engagement with fragile states to inform the design of health programmes and selection of interventions depends on donor coordination and an understanding of health system challenges. Planning requires consideration of allocation (services to be delivered), production (organisation of services), distribution (beneficiaries of services) and financing. The criteria for selecting interventions are: their impact on major health problems; effectiveness; the possibility of scale-up; equity; and sustainability. There are various options for financing and models of engagement, but support should always combine short-term relief with longer-term development. Stakeholders should aim not only to save lives and protect health but also to bolster nations' ability to deliver good-quality services in the long run.     

富营养浅水湖泊的退化与生态恢复

初步讨论了富营养浅水湖泊的退化现象的造成退化的主要原因，对湖泊生态恢复的目标和对策等问题也作了探讨，以武汉东湖为例，提出以水源保护地为主要功能的富营养浅水胡泊的恢复和整体优化对策，即恢复沉水植被、建立控制面源污染的半自然的人工湿地生态系统，优化水产养殖结构和恢复湖泊生物多样性等。对生物操纵在长江中下游富营养浅水湖泊恢复中的作用也进行了讨论。     

The State of Protected Forest Communities in the European Forest–Steppe Zone of Russia and Prospects for Their Reconstruction: A Case Study of Specially Protected Areas of Penza Oblast

The structure of most forest communities in the European forest–steppe, including protected areas, has been disturbed. The adverse consequences of these disturbances include the incomplete age structure of the populations of cenosis-forming species and the irreversibility of successions. The conservation of biodiversity in the structurally disturbed communities is impossible without human intervention, which must be aimed at restoring their age heterogeneity with regard to their specific ecological features.     

河西走廊地区农垦企业的地域发展特征与问题诊断

河西走廊地区的农垦企业对当地经济的发展起到了示范、带动和辐射作用，是拉动当地经济发展的一驾马车。本文通过对农垦企业的典型调查。分析了政策因素、农业资源条件和运费因素对农垦布局的影响，并讨论了农垦企业的发展特征。重点阐述了农垦企业的发展中存在的问题，主要包括不合理的产业结构、实现产业化经营的难度、企业办社会造成了沉重的社会负担、过高的企业负债率、人才结构不合理、未享受到正常的国民待遇以及与所在区域难以实现协调发展。基于上述分析，提出了协调农垦企业与区域经济发展的合理机制。     

Performance evaluation of Nahar oil–diesel blends in a single cylinder direct injection diesel engine

This study attempts to use plentiful available high oil content (67% of Nahar seed kernel) non-edible feedstock as a source for powering diesel engine. Various performance and emission characteristics of prepared Nahar oil–diesel blends (5%, 10%, 20%, 30%, and 40%) are analyzed in a single cylinder direct injection diesel engine at different load spectrum, in order to judge the optimum blend, which can be efficiently used in a diesel engine. 10% blending of Nahar oil with diesel fuel has shown a reduction in hydrocarbon and carbon monoxide emission by 8.64% and 8.34%, respectively. With the increase in blend concentration, the nitrogen oxide emission decreased considerably and smoke emission increased slightly. Further pressure crank angle and heat release rate analysis of 10% blending of Nahar oil with diesel confirms its smooth combustion inside the engine combustion chamber.     

A low pressure direct gas injection system for a four stroke LPG: Diesel dual fuel engine

Internal combustion engines running on gaseous fuels produce low torque because the inducted gaseous fuel displaces air and reduces the volumetric efficiency. This can be overcome by injecting the gaseous fuel directly into the cylinder after the intake of air is completed. This work is a step in developing and demonstrating a cost effective system, as such systems are not readily available for small applications. A low-pressure gas injector was mounted on the cylinder barrel of a fully instrumented dual fuel engine. Its location is such that the injector will be exposed to the cylinder gases about 65.5 degrees before bottom dead center, where the cylinder pressure and temperature will be relatively low. An electronic controller was also developed to time the injection process to occur after the intake valve closes and also to control the duration of injection (quantity). Experiments were conducted with LPG (Liquefied petroleum gas) as the primary fuel that was injected with this new system and diesel as the pilot fuel at the rated speed of 1500 rpm with different amounts of LPG at 80% and 100% load. Comparisons of performance, combustion and emissions with the conventional manifold injection of LPG were done. The system allowed greater amounts of LPG to be used without knock as compared to manifold injection. On the whole the developed system has potential for application in small dual fuel and spark ignited gas engines and can be taken up for further optimization.     

Alternative function fulfilment: incorporating environmental considerations into increased design space

The focal point of this paper is the relatively unknown concept of alternative function fulfilment (AFF), which is a design strategy that can be used to generate new ways of fulfilling a certain function and is referred to in the context of ecodesign. It can be considered an attractive environmental innovation strategy, provided that the increased design space is used to create more sustainable products and services.This paper explores the AFF concept and discusses the implications of adopting this concept. It thus focuses on how design and business processes may need to change to allow the radical shift towards AFF, in order to facilitate the envisaged significant environmental improvements.     

Maximising the net social benefit of the construction of post‐disaster alternative housing projects

The widespread destruction that follows large‐scale natural disasters, such as Hurricane Katrina in August 2005, challenges the efficacy of traditional temporary housing methods in providing adequate solutions to housing needs. Recognising these housing challenges, the Congress of the United States allocated, in 2006, USD 400 million to the Department of Homeland Security to support Alternative Housing Pilot Programs, which are intended to explore the possibilities of providing permanent and affordable housing to displaced families instead of traditional temporary housing. This paper presents a new methodology and optimisation model to identify the optimal configurations of post‐shelter housing arrangements to maximise the overall net socioeconomic benefit. The model is capable of quantifying and optimising the impacts of substituting temporary housing with alternative housing on the social and economic welfare of displaced families as well as the required additional costs of doing so. An application example is presented to illustrate the use of the model and its capabilities.     

蒙特卡洛法计算750kV输电线路绕击跳闸率的研究

利用GDS多功能三轴仪,通过控制土样应变增量比开展了饱和砂土部分排水三轴试验;利用超静孔隙水压力、有效应力路径和应力应变关系三方面的实验结果,研究了饱和砂土的渐近状态特性。研究表明,控制应变增量比为常数进行常规三轴加载时,饱和砂土的有效应力比也趋于某一常数,形成渐近状态,且渐近状态应力比随应变增量比的增大而减小。基于土的剪胀特性给出了渐近状态形成的物理机制,并给出了北京某砂土在部分排水条件下渐近状态应力比的试验结果。