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1.
This paper reports the results of research conducted to study the fuel properties of Honge oil and blends of its ester and the subsequent testing of these oils in a four‐stroke, single cylinder, water‐cooled, direct injection, compression‐ignition (CI) engine. Experiments were conducted with injection timings of 19, 23 and 27° BTDC at various loads and at a constant rated speed of 1500?rev?min?1. The performance and emission characteristics of Honge oil and Honge oil methyl ester (HOME) blended with diesel, to produce blends designated B20, B40 and B80, were studied. The heat release rates, maximum rate of pressure rise, ignition delay, and combustion duration for these fuel combinations were determined.  相似文献   

2.
Recovery of used products has become a field of rapidly growing importance in reverse supply chain management. Product recovery includes collection, inspection/separation, disassembly, reconditioning/reuse, remanufacturing, and recycling. In real time situations, the collection of end‐of‐life (EoL) products from the customer and their return to the manufacturer is tedious and time consuming. Reduced product life cycles have increased the rate of product returns and disposals. Owing to shortened product economic life cycles, the recovery of value from EoL products is becoming a necessity. Companies have realised the value that they could recover by remanufacturing or recycling EoL products. Researchers have developed various models for product recovery network design, optimal inventory, production planning and control, remanufacturing, recycling, disposal, etc. The main purpose of this paper is to review the literature on EoL product recovery and inventory management issues in reverse supply chains and to outline some future directions for research on these issues.  相似文献   

3.
Following a brief introduction about the need for businesses to respond to climate change, this paper considers the development of the phrase ‘carbon footprint’. Widely used definitions are considered before the authors offer their own interpretation of how the term should be used. The paper focuses on the contribution small and medium sized enterprises (SMEs) make to the economy and their level of influence in stimulating change within organisations. The experience of an outreach team from the Engineering Department of a UK university is used which draws on the experience of delivering regional economic growth projects funded principally through the European Regional Development Fund. Case studies are used including the development of bespoke carbon footprints for SMEs from an initiative delivered by the outreach team. Limitations of current carbon footprints are identified based on this higher education‐industry knowledge exchange mechanism around three main themes of scope, the assessment method and conversion factors. Evidence and discussions are presented that conclude with the presentation of some solutions based on the work undertaken with SMEs and a discussion on the merits of the two principally used methodologies: life‐cycle analysis and economic input–output assessment.  相似文献   

4.
A chemical pathway combining reverse water gas shift, Fischer‐Tropsch synthesis and hydro‐cracking was considered to re‐synthesise jet fuel from CO2 captured at high purity by oxy‐fuelling of a typical coal‐fired power station (Drax, UK). The oxygen for oxy‐fuelling and hydrogen for the fuel re‐synthesis process are sourced by electrolysis of water. According to material and energy balances , 3.1 MT/year of jet fuel and 1.6 MT/year each of gas oil and naphtha can be produced from the Drax annual emissions of 20 MT of CO2, sufficient to supply 23% of the UK jet fuel requirements. The overall re‐synthesis requires 16.9 GW, to be sourced renewably from (offshore) wind power, and releases 4.4 GW of exothermic energy giving scope for improvements via process integration. The energy re‐synthesis penalty was 82% ideally and 95% on a practical basis. With the cost of offshore wind power predicted to reduce to 2.0 p/kWh by 2020, this ‘re‐syn’ jet fuel would be competitive with conventional jet fuel, especially if carbon taxes apply. The re‐use of CO2 sequestrated from coal power stations to form jet‐fuel would halve the combined CO2 emissions from the coal power and aviation sectors.  相似文献   

5.
The presence of the synthetic estrogen 17α-ethinylestradiol (EE2) in waters at low levels is a concern due to its ability to act as an endocrine disruptor. Ozone (O3) is commonly used in water treatment and reacts with EE2 to form by-products having characteristics that are mostly unknown. The aim of this study was to identify the by-products of E2 and EE2 ozonation and determine their estrogenicity and toxicity relative to the parent compound. Ozonation by-products were identified via LC-MS analysis. The estrogenicity was measured using the YES assay, and toxicity was determined by monitoring effects on histology of fetal rat testes and testosterone secretion by these tissues. Two EE2 by-products were identified with open phenolic ring structures (masses 302 and 344 u). The Yeast Estrogen Screening (YES) assay showed a decreased but incomplete removal of estrogenicity after ozonation of EE2. Histological analysis of fetal testes revealed that neither E2 nor EE2, with or without ozonation, had any effect on seminiferous cord formation; however, a remarkable negative effect on testosterone secretion was observed, with EE2 by-products after ozonation showing the most rapid and extensive inhibition. These results show that the removal of EE2 via reaction with O3 resulted in the formation of by-products that are less estrogenic (as demonstrated by the YES assay), but have a greater negative impact on testosterone secretion. Thus, the disappearance of the parent compound is not a sufficient endpoint, as the by-products created may be more toxic. Care should be taken when implementing oxidation applications such as ozone during waste water treatment.  相似文献   

6.
Although chemical control of pests increases crop production, it brings a lot of damage to environment and human health. There exist a number of alternative methods that are not so harmful to environment and human health. However, whether and how much in extent these technologies adopted are plausible depends on the comparison of benefit-cost between chemical control and the alternative control methods (such as Integrated Pest Management, IPM) and farmers' willingness-to-pay (WTP) for envirorment and human health. Using contingent valuation method (CVM), the author investigates farmers' WTP for environment and human health, recognizes the factors influencing WTP, and accordingly points out the importance of pest control technology extension and government regulation of pesticides.  相似文献   

7.
The issue of agricultural insurance subsidy is discussed in this paper aiming to make it provided more rationally and scientifically. It is started with the connection between agricultural insurance and financial subsidy. It is really necessary and crucial to implement the financial insurance due to the bad operational performance, especially in the developing countries. But the subsidy should be provided more rationally because financial subsidy has lots of negative effects. A model in competitive insurance markets developed by Ahsan et al (1982) and a farmers' decision model are developed to solve the optimal subsidized rate. Finally, the equation is got to calculate it. But a quantitative subsidized rate is not made here because the calculation should be under some restricted conditions, which are always absent in the developing countries. So the government should provide some subsidy for the ex ante research and preparation to get the scientific probability and premium rate.  相似文献   

8.
Engineered nanomaterials (ENM) are expected to hold considerable potential for products that offer improved or novel functionalities. For example, nanotechnologies could open the way for the use of textile products outside their traditional fields of applications, for example, in the construction, medical, automobile, environmental and safety technology sectors. Consequently, nanotextiles could become ubiquitous in industrial and consumer products in future. Another ubiquitous field of application for ENM is fa?ade coatings. The environment and human health could be affected by unintended release of ENM from these products. The product life cycle and the product design determine the various environmental and health exposure situations. For example, ENM unintentionally released from geotextiles will probably end up in soils, whereas ENM unintentionally released from T-shirts may come into direct contact with humans and end up in wastewater. In this paper we have assessed the state of the art of ENM effects on the environment and human health on the basis of selected environmental and nanotoxicological studies and on our own environmental exposure modeling studies. Here, we focused on ENM that are already applied or may be applied in future to textile products and fa?ade coatings. These ENM's are mainly nanosilver (nano-Ag), nano titanium dioxide (nano-TiO(2)), nano silica (nano-SiO(2)), nano zinc oxide (nano-ZnO), nano alumina (nano-Al(2)O(3)), layered silica (e.g. montmorillonite, Al(2)[(OH)(2)/Si(4)O(10)]nH(2)O), carbon black, and carbon nanotubes (CNT). Knowing full well that innovators have to take decisions today, we have presented some criteria that should be useful in systematically analyzing and interpreting the state of the art on the effects of ENM. For the environment we established the following criteria: (1) the indication for hazardous effects, (2) dissolution in water increases/decreases toxic effects, (3) tendency for agglomeration or sedimentation, (4) fate during waste water treatment, and (5) stability during incineration. For human health the following criteria were defined: (1) acute toxicity, (2) chronic toxicity, (3) impairment of DNA, (4) crossing and damaging of tissue barriers, (5) brain damage and translocation and effects of ENM in the (6) skin, (7) gastrointestinal or (8) respiratory tract. Interestingly, some ENM might affect the environment less severely than they might affect human health, whereas the case for others is vice versa. This is especially true for CNT. The assessment of the environmental risks is highly dependent on the respective product life cycles and on the amounts of ENM produced globally.  相似文献   

9.
The coming together of a number of initiatives provided a springboard for an innovative pilot programme in education for sustainable development. For some time problem‐based learning has gathered momentum as an approach to educating professionals. More recently, there has been a burgeoning interest in inter‐disciplinary approaches to the complex societal and environmental issues that face the world as a whole. At the same time, professional engineering institutions have been reflecting on appropriate approaches to the education and development of future engineers. Building on work already undertaken by some of the authors, the Royal Academy of Engineering sponsored an inter‐disciplinary pilot programme in sustainable development for undergraduate engineers and scientists in the University of Manchester. The pilot was innovative not only in its inter‐disciplinary approach to sustainable development but also in its approach to the development of the curriculum. Inter‐disciplinary exercises were designed that enabled a contextual, active, collaborative and cumulative approach to learning. The assessment was also designed to align to the learning approach. Evaluation of the pilot programme suggests that it was well received by the students, and the post‐doctoral researchers who acted as facilitators, and also that there were gains in both understanding of the issues and also in approaches to learning.  相似文献   

10.
11.
Energy is now becoming the bottleneck of urban and regional development. The paper takes Shandong Province, one of the most energy consuming provinces in China, as an example, uses quantity methods such as SPSS (Stastics Package for Social Science) cluster sampling and regression analysis, and applies quantity analysis, to analyze the situation of energy issues in Shandong province. The conflicts between the quick industrialization and increasing extensive economic development, between urban population and energy consuming per head, between the infinite energy consuming desire and the low level of managing system, and between the unstable world energy supply and the limited energy storage in China are the main factors of energy crisis in Shandong, which not only results in energy shortage, but also becomes the barrier of economic and social development. In order to ensure sufficient energy supply for Shandong province in the 21 st century, we should take countermeasures, such as changing the economic development model, pursuing a multiple and high quality energy strategy, improving the intensive urbanization strategy, and building a scientific energy system.  相似文献   

12.
1INTRODUCTIONAncient lakes are lakes that once existed in history,butnow have died out.As a kind of land water and geomorphicconfiguration,the formation and evolution of ancientlakes were closely linked with the variance of geographicenvironment.The south coast plain of Laizhou Bay is aplain extending from the estuary of the Xiaoqing Riverin the west to the estuary of the Jiaolai River in the east.There were once some lakes on the plain in history,suchas Judian Lake,Qingshuibo Lake,an…  相似文献   

13.
The Ganges–Brahmaputra delta enables Bangladesh to sustain a dense population, but it also exposes people to natural hazards. This article presents findings from the Gibika project, which researches livelihood resilience in seven study sites across Bangladesh. This study aims to understand how people in the study sites build resilience against environmental stresses, such as cyclones, floods, riverbank erosion, and drought, and in what ways their strategies sometimes fail. The article applies a new methodology for studying people’s decision making in risk-prone environments: the personal Livelihood History interviews (N = 28). The findings show how environmental stress, shocks, and disturbances affect people’s livelihood resilience and why adaptation measures can be unsuccessful. Floods, riverbank erosion, and droughts cause damage to agricultural lands, crops, houses, and properties. People manage to adapt by modifying their agricultural practices, switching to alternative livelihoods, or using migration as an adaptive strategy. In the coastal study sites, cyclones are a severe hazard. The study reveals that when a cyclone approaches, people sometimes choose not to evacuate: they put their lives at risk to protect their livelihoods and properties. Future policy and adaptation planning must use lessons learned from people currently facing environmental stress and shocks.  相似文献   

14.
Demographic urbanization caused great changes in scale of residents’ consumption and residents’ lifestyle and then impacted changes of regional household energy consumption. This paper expanded Logarithmic Mean Decomposition Index method through introducing variables of urbanization and residential consumption into the model. It also analyzed the influences of six factors as energy structure, energy intensity, population scale, urbanization, residential consumption, and consumption inhibit on regional household energy consumption. Results showed that in 2003–2012, impact of urbanization on regional household energy consumption of Chinese three areas was significantly higher than population size. The “population gathered in eastern region” phenomenon caused eastern region getting the largest population scale effect. Driving force of residential consumption on regional household energy consumption was much higher than the other five effects. Due to the comparative advantage of residential consumption compared with government consumption, investment, and net export, the decrease of consumption ratio promoted the growth of regional household energy consumption. Energy intensity in Chinese three regions kept reducing in 2003–2012. The progress of energy utilization technology slowed the growth of regional household energy consumption, and energy intensity effect was most significant in the central region.  相似文献   

15.
This paper discusses the basic concept and connotation of population modernization. The author briefly analyzes the actuality of population modernization in China, gives some advice and puts forward some measures.  相似文献   

16.
Urban Agglomeration is an inevitable outcome of urbanization and industrialization, and a main form of urban development. Based on the analysis of urbanization and urban system situation, this paper will discuss the integration of urban agglomeration development, using the urban area of Cheng (Chengdu)-Yu (Chongqing) Urban agglomeration (CYUA) as a case study. By means of industries, population and spatial integrations, the function, strength and competition of CYUA will be improved and this urban agglomeration will transit from a budding state to a growing and mature one in future. The sustainable development of CYUA will depend on countermeasures, such as accelerating industrialization and urbanization, building a traffic network and express roads, strengthening the ability of self-sufficiency, enlarging the ecological construction and environmental protection, and establishing the synergetic institution of cross districts.  相似文献   

17.
The Chinese Journal of Population, Resources and Environment(CJPRE Chinese Edition and English Edition) is an academic periodical jointly Sponsored by the Chinese Society for Sustainable Development, the Research Center for Sustainable Development of Shandong Province, the Administrative Center for China's Agenda 21 and Shandong Normal University. Mr. Deng Xiaoping, our respected general designer of China's reform and opening policy, paid great attention to the issues of population, resources and environment in sustainable development. He inscribed the Chinese name of the Journal and placed great expectation and responsibility on the journal.  相似文献   

18.
In early 2009, few would have expected that the Intergovernmental Panel on Climate Change (IPCC) would come under such massive attack. The IPCC had enjoyed a pristine reputation and had even advanced to become a role model for biodiversity and food security assessments (Loreau et al. 2006; Watson 2005). However, public trust and, with it, the organization’s credibility eroded dramatically after November 2009 with the events that became known as ‘climategate’. This article seeks to contribute to current debates about how to reform the IPCC. It argues that there are major flaws in the design of the IPCC which are rooted in the linear model of expertise and which are helping to stoke the backlash against the IPCC. The article analyzes the ways in which the IPCC’s activities conform to the linear model of expertise and considers the consequences of this for integrating adaptation into the IPCC assessments. It explains why adaptation played only a marginal role up until the IPCC Third Assessment Report. It then demonstrates why the use of the linear model of expertise constrains the scientific and political debate about adaptation and leads to proxy debates about scientific evidence, which result in depoliticizing the politics of adaptation and politicizing science. Finally, the article calls for the debate to be opened up to accommodate alternatives that are both politically more feasible and at the same time more appropriate to the specific needs of adaptation policies at different levels of decision-making.  相似文献   

19.
China's circular economy is still at the initial stage, whose development has many difficulties and problems requiring immediate resolution theoretically and practically. Due to the differences of regions on the scale of land, endowment of resources, economic basis and cultural background, the developmental levels and capabilities of circular economy are inevitably different. Based on establishing the indicator system for assessing the developmental level of regional circular economy, spatial variation of China's circular economy is measured by the quantitative measurement using principal component analysis, and the existing problems are also analyzed and discussed. On one hand, the differences of the development capability of the circular economy of different provinces (cities) are profound in China; ①Difference between the first category (strong) and the second category (relatively strong) is 1.1264 points. Difference between the second category and the third category (relatively weak) is 0.3867 points. Difference between the third category and the fourth category (weak) is 1.0238 points. Difference between the first category and the fourth category reaches up to 2.0869 points. Average difference between the area where the developmental level of circular economy is relatively strong and the area where the developmental level of circular economy is relatively weak is 1.3617 points. ②The differences of the distribution of the areas, with different development capability of circular economy, which are located in the three economic regions of China, are also profound. The regions with a relatively strong development capability of circular economy are mainly located in the eastern economic area, which account for 22.58% of the whole regions, while only account for 12.90% in the middle and western economic areas. On the contrary, the regions with a relatively weak development capability of circular economy account for 48.39% in the middle and western area, while account for 16.13% in the eastern area. On the other hand, among regions with different development capability of circular economy, the regions with a relatively weak development capability of circular economy are in a dominant position, which accountfor 64.52% of all the provinces (cities), which indicates that the development of the China's circular economy still has a long way to go. Though certain achievements have been made in the development of China's circular economy, in general, there are still some obstacles to be tacked in the development of China's circular economy which require the economic, legal and administrative methods.  相似文献   

20.
Picea neoveitchii is an endemic species in China. It had been listed as an endangered species in red data books. It scatters in several locations of south slope of the Qinling Mountain of China. Upon reviewing the related literature, discussing with leading scholars on gymnosperm, ecology and plant conservation, the field survey was carried out in four locations. There are eleven mature individuals and two seedlings surviving in its natural habitats. With the survey of quadrat method in four locations, related community index were calculated such as relative important value (RIV), species richness, similarity index, diversity index and evenness index etc. The community could be sorted and characterized as three groups based on the community parameters. The analysis of vegetation table elucidates that Picea neoveitchii is a dominant species with low grouping rate in most surveyed sites. The RAPD analysis shows target species has intraspecific genetic variability. The estimation of Shannon's phenotypic diversity index (Ho) also explains the difference of genetic variations of different locations. Due to the lack of enough knowledge and professional guide of conservation biological perspective, Picea neoveitchii had been clear-cut for timber production. The extent of occurrence and area of occupancy declined rapidly from 1950s to 1990s. According to the Conservation Category guideline proposed by the World Conservation Union, the conservation status of Picea neoveitchii was reevaluated as Critically Endangered (CR) B2b C2a D. Upon research in areas of ecology, molecular biology, cluster analysis of environmental parameters, a practical conservation strategy is recommended in this research.  相似文献   

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