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1.
This paper briefly describes a linear programming model designed to allow the exploration of questions surrounding the management of the environmental impacts of integrated iron and steel facilities. In particular, the model can show how plant discharges will change in the absence of specific legal restrictions or effluent charges, with such variables as product mix, steel-furnace type, casting technology, and the scrap-ore price ratio. In addition, the costs implied by placing restrictions on discharges of specific residuals (e.g., BOD, oil, suspended solids, particulates) may be estimated, or response to proposed effluent charges may be predicted.  相似文献   

2.
This paper estimates the average social cost of municipal waste management as a function of the recycling rate. Social costs include all municipal costs and revenues, costs to recycling households to prepare materials estimated with an original method, external disposal costs, and external recycling benefits. Results suggest average social costs are minimized with recycling rates well below observed and mandated levels in Japan. Cost-minimizing municipalities are estimated to recycle less than the optimal rate. These results are robust to changes in the components of social costs, indicating that Japan and perhaps other developed countries may be setting inefficiently high recycling goals.  相似文献   

3.
In this paper, a theoretical model of secondary recovery is developed that integrates microeconomic theories of production and cost with a dynamic model of scrap generation and accumulation. The model equations are estimated for the U.S. secondary copper industry and used to assess the impacts that various policies and future events have on copper recycling rates. The alternatives considered are: subsidies for secondary production, differing energy costs, and varying ore quality in primary production.  相似文献   

4.
Recycling of household wastes may not contribute as much toward a solution to environmental problems as widely supposed. It runs into practical problems often overlooked by nonspecialists. Recycling can also contribute significantly to pollution. Most important, recycling may use up larger quantities of materials than it saves. The note ends up with a model in which recycling will always cause a net loss in real resources. It is concluded that the subject requires more exploration rather than decision making by prejudgment and emotion.  相似文献   

5.
循环经济持续发展的价值链机制   总被引:9,自引:0,他引:9  
循环经济的正常运行,必须有价值链的支持。循环型产业的价值形成机制是循环经济持续发展的关键。而且,经济价值链一旦形成,其意义就不仅在经济本身,还具有社会价值和生态价值的重要意义,是在更高的意义上对经济价值、社会价值和生态价值的整合。  相似文献   

6.
Environmental protection and sustainable development are getting increasing attention in the automobile industries. Environmental consciousness has increased, and sustainability has become an important requirement for the management of end-of-life vehicles (ELVs). The proper management of ELVs can bring improved sustainability performance for any society or organisation. There are several alternative options for ELVs management such as reuse, repair, reconditioning, remanufacturing and recycling. Environmental legislation is forcing original equipment manufacturers (OEMs) to manage their products at the end of their life cycle to reduce their potential environmental impact. An appropriate selection model for sustainable ELV management alternatives in the dynamic, competitive and regulatory environment can enable a firm to satisfy economic, environmental, social and technological requirements. This study proposes an integrated model to select the dimensions and criteria for evaluating sustainable alternatives for the proper management of ELVs. First, the Decision-Making Trial and Evaluation Laboratory (DEMATEL) method is used to select the most important dimensions and criteria for sustainable alternative selection. Next, a hierarchy has been constructed to develop a systematic technique to solve the alternatives selection problem. An analytic hierarchy process (AHP) and extent analysis method on the fuzzy AHP (FEAHP) model have been used based on the hierarchy to evaluate the most suitable alternatives from the sustainability point of view. The strength of the proposed model is that it compares the results of both methods, the imprecision of experts’ opinions is considered in the evaluation process and the model is easy to use.  相似文献   

7.

Purpose

The purpose of the study is the enhancement of criticality assessments for resources in order to address function specific factors like dissipation, recycling, bio-activity and toxicity. The developed methodology is applied to platinum-containing cytostatic drugs and automotive catalytic converters.

Methods

The study is methodically based on an analysis of resource specific factors like exploration rates, reserves-to-production ratio and regional distribution of exploration areas as well as on the investigation of product/functional depending factors like recycling rates, dissipation rates, bio-diversity and toxicity. Taking into account that economic and ecological risks may occur at any stage of the supply, consumption and dissipation processes, the whole life cycles of the two analyzed products (cytostatic drugs and automotive catalytic converters) are considered. As an approach to reduce potential economic and ecological risks the study is especially focused on recycling strategies.

Background

In order to get a better understanding of platinum as an essential resource for the development of our society the history and the cultural impact of the term "resource" are introduced.

Results & Discussion

The availability of platinum is crucial for several products of our modern society. Areas of application are e.g. jewellery, automotive catalytic converters, investments (coins, bars), computers, mobile devices, fertilizers and cytostatic drugs. Economic risks are caused by limited sources and dynamic demand of new application areas like fuel cells and drugs. Platinum-containing drugs are used for the treatment of several kinds of cancer such as testicular, breast, colon and prostate. Currently the pharmaceutical industry requires 6,9 tons per year (3 percent of the total demand of platinum). Due to the improvement of medical standards and the ageing society, especially in developing countries, the demand of platinum-containing drugs will rise significantly. The dissipation of toxic soluble salts and the lack of advanced waste-water treatment and recycling systems is a problem of the usage of platinum-containing drugs. Compared with cytostatic drugs (14.6 kg/a for Germany) the dissipation of platinum particles of mobile catalytic converters is much higher (5-20 tons/a only in North America, Europe and Japan; 184,2 kg/a in Germany). On the other hand the emission of platinum nano-particles of automotive catalytic converters seems less critical. Furthermore advanced recycling technologies are already available for them.

Conclusions

The evaluation of resources has to consider resource specific and functional depending factors. In order to reduce economic and ecological risks of the dissipation of platinum salts in cytostatic drugs three principle options can be identified: the development of ecologically compatible and cost-effective substitutes, efficient recycling systems and future-oriented sanitary-systems as well as waste-water treatment facilities, which are able to separate platinum salts. Concerning the dissipation of platinum particles of mobile converters relevant research questions are the identification of adequate substitutes as well as the extension of recycling capacities.

Recommendations and perspectives

The study demonstrates a research gap concerning substitutes for automotive catalytic converters as well as for platinum-containing cytostatic drugs. The development and implementation of recycling concepts, technologies and capacities to reuse platinum as a secondary resource is an essential issue. As a consequence the economic and ecological risks can be reduced by increasing the resource efficiency. Special research has to be done concerning the development of future-oriented sanitary-systems and waste-water treatment facilities in order to separate platinum in waste water. Furthermore, if the future demand of new products like fuel cells is considered, a resource conflict concerning the potential functional applications will be evident. In order to address these challenges the criticality assessment has to be enhanced by ethic and social factors.  相似文献   

8.
Imposing environmental taxation on external costs of energy will not only affect the environmental impact of the energy sector itself, but it will tend to decrease environmental damage from other sectors of the economy as well. We have assessed the effects of a shift of taxation from taxing labour to taxation of external costs caused in the energy sector. Several examples give results compatible with the hypothesis that the changing price relation between labour and energy resulting from such a tax shift will make re-use, repairs and recycling increasingly competitive and thus tend to decrease mining as well as waste production. Likewise, less energy-intensive commodities and services in general would become increasingly competitive, and would tend to decrease the environmental load further. These environmentally desirable effects are beyond the taxed external effects of the energy sector itself and occur as an indirect effect of the increased relative price of energy.  相似文献   

9.
Understanding the social dimensions of conservation opportunity is crucial for conservation planning in multiple‐use landscapes. However, factors that influence the feasibility of implementing conservation actions, such as the history of landscape management, and landholders’ willingness to engage are often difficult or time consuming to quantify and rarely incorporated into planning. We examined how conservation agencies could reduce costs of acquiring such data by developing predictive models of management feasibility parameterized with social and biophysical factors likely to influence landholders’ decisions to engage in management. To test the utility of our best‐supported model, we developed 4 alternative investment scenarios based on different input data for conservation planning: social data only; biological data only; potential conservation opportunity derived from modeled feasibility that incurs no social data collection costs; and existing conservation opportunity derived from feasibility data that incurred collection costs. Using spatially explicit information on biodiversity values, feasibility, and management costs, we prioritized locations in southwest Australia to control an invasive predator that is detrimental to both agriculture and natural ecosystems: the red fox (Vulpes vulpes). When social data collection costs were moderate to high, the most cost‐effective investment scenario resulted from a predictive model of feasibility. Combining empirical feasibility data with biological data was more cost‐effective for prioritizing management when social data collection costs were low (<4% of the total budget). Calls for more data to inform conservation planning should take into account the costs and benefits of collecting and using social data to ensure that limited funding for conservation is spent in the most cost‐efficient and effective manner.  相似文献   

10.
SUMMARY

Sustainable decision-making requires consideration of technology, ecology, and the social and political infrastructure of society. While it may never be possible to identify with certainty what is sustainable and what is not, an attempt has been made in this paper to formulate a measure that permits one to compare the performances of project alternatives with respect to risk. An algorithm is presented for the evaluation of a risk criterion that can be used with other criteria in the process of selecting project alternatives. The intent of the risk criterion is to involve project stakeholders in the process of quantifying the risks associated with different project alternatives.  相似文献   

11.
In this paper we focus on how an international climate treaty will influence the exploration of oil in non-OPEC countries. We present a numerical intertemporal global equilibrium model for the fossil fuel markets. The international oil market is modelled with a cartel (OPEC) and a competitive fringe on the supply side, following a Nash–Cournot approach. An initial resource base for oil is given in the non-OPEC region. However, the resource base changes over time due to depletion, exploration, and discovery. When studying the effects of different climate treaties on oil exploration, two contrasting incentives apply. If an international carbon tax is introduced, the producer price of oil will drop compared to the reference case. This gives an incentive to reduce oil production and exploration. However, the oil price may increase less rapidly over time, which gives an incentive to expedite production and exploration. In fact, in the case of a rising carbon tax we find the last incentive to be the strongest, which means that an international climate treaty may increase oil exploration in non-OPEC countries for the coming decades and reduce OPEC's market share.  相似文献   

12.
SUMMARY

The development of Industrial Ecology (IE) is based on the philosophy that the two systems, the industrial system and the ecosystem operate through different principles of system development and on the philosophy that IE can serve to reduce the conflict between the two systems as it learns from the model of an ecosystem. In an IE, following the roundput analogy of a natural ecosystem, the industrial actors co-operate by utilising each other's waste material and energy flows and try and reduce the system virgin material and energy input as well as the waste and emission output. In a successful IE, a business-environment win-win might be possible because the raw material and energy costs, waste management costs, costs resulting from environmental legislation, as well as the image costs of the companies in the system and of the system as a whole, can be reduced. In this paper, the IE analogy includes the four basic principles of system development of ecosystems; roundput, diversity, locality and gradual change. The principles are understood as a potential direction in which Regional Industrial Ecosystem Management (RIEM) can be developed.  相似文献   

13.
Petroleum fuels are the primary energy basis for transportation and industry. They are almost always an important input to the economic and social activities of humanity. Emergy analyses require accurate estimates with specified uncertainty for the transformities of major energy and material inputs to economic and environmental systems. In this study, the oil refining processes in Italy and the United States were examined to estimate the transformity and specific emergy of petroleum derivatives. Based on our assumptions that petroleum derivatives are splits of a complex hydrocarbon mixture and that the emergy is split based on the fraction of energy in a product, we estimated that the transformity of petroleum derivatives is 65,826 sej/J ± 1.4% relative to the 9.26E+24 sej/year planetary baseline. Estimates of the specific emergies of the various liquid fuels from Italian and U.S. refineries are within 2% of one another and the relationship of particular values varies with the refinery design. Our average transformity is only 1.7% larger than the current estimate for petroleum fuels determined by back calculation, confirming the accuracy of this transformity in existing emergy analyses. The model uncertainty between using energy or mass to determine how emergy is split was less that 2% in the estimate of both the transformity and specific emergy of liquid fuels, but larger for solid and gaseous products. This study is a contribution to strengthen the emergy methodology, providing data that can be useful in the analysis of many human activities.  相似文献   

14.
High relatedness among society members is believed important for the evolution of highly cooperative behaviours, yet queens of many social insects mate with multiple males which reduces nestmate relatedness and imposes also direct costs on queens. While theoretical models have suggested explanations for this puzzling queen behaviour, empirical studies fail to provide consistent answers especially for species with moderate levels of multiple mating. This may result from multiple mating only conferring benefits in some environments, as suggested by recent genetic variance theory and considerations on types of traits, direct costs and benefits. All concur in an expectation of higher levels of multiple mating in more complex or milder environments, and we perform a first, broad test of this idea by comparing mating strategies of queens in Lasius niger ants from northern (harsh, cold stressed) and southern populations (milder, greater bio-complexity). First, we collected new genetic data from Ireland and Southern France and then compared these to data on Swiss and Swedish populations. Queens from northern populations were near exclusively single mated and even at times inbred (in Ireland), whereas southern queens showed high levels of multiple mating, leading to more genetically diverse colonies in the south. Equally, paternity skew was greater in the north, as expected if northern queens only remate when their first mate transfers few sperm. Our findings are consistent with the idea that environment type may affect mating strategies in social insects and calls for an exploration of such effects.  相似文献   

15.
This paper presents a model that combines within and across sector channels through which trade affects our environment by embedding heterogeneous firms and fixed costs into a two-sector framework with an endogenous response to environmental policy. In contrast to existing literature that tends to examine these channels separately, the combined framework developed here shows how cross-sector comparative advantage and within-sector responses to trade and environmental policy or factor endowments interact to affect our environment through three channels: changes in output, cross-sector market share, and emissions intensity. In contrast to a single-sector model with neutral productivity, consideration of two sectors allows for trade liberalization to affect the allocation of inputs in each sector and thereby affect total pollution output. The additional consideration of heterogeneous firm responses to falling trade costs will generate endogenous increases in productivity that increase output, reduce aggregate emissions intensity, and moderate the cross-sector resource adjustment, relative to a representative-firm model. Simulation results show how the combined framework can replicate existing empirical outcomes, and provide concise ceteris paribus insights regarding the potential role of trade and environmental policy changes and factor expansion in driving observed outcomes and their contribution to each of the three channels.  相似文献   

16.
The principal purpose of this paper is to discuss the research and policy lessons learned from a large environmental quality management model constructed for the Lower Delaware River Valley Region, The policy lessons involve estimates of the costs of meeting varying standards on air and water quality and the impact on those costs of certain region-wide management alternatives. The research lessons concern: (a) the desirability of considering air and water quality, and solid waste disposal, simultaneously in a single model; (b) the costs of and returns to including nonlinear models of natural systems in a regional optimization framework; and (c) the feasibility of working with constraints on the geographic distribution of the costs of environmental quality improvement within the regional, nonlinear model.  相似文献   

17.
In recent years, much attention has been given to the desulphurization of fuels like diesel oil and gasoline, since exhaust gases containing SOx cause air pollution and acid rain. Moreover, a lower sulphur content of fuels would allow the use of new engines and catalytic systems for the reduction of CO, particle and NOx-emissions, and a more efficient fuel consumption. The S-level in fuels is presently limited in Germany for gasoline and diesel oll to 150 ppm and 350 ppm, respectively. In 2005 the level will be decreased Europe-wide for all vehicle-fuels down to 50 ppm; in some countries, fuels are or will be on the market with even less sulphur. The current technology of hydrodesulphurization (heterogeneous, catalyzed hydrorreating of organic sulphur compounds) can desulphurize quite adequately down to today’s S-level. The process, however, is limited for the production of ultra-low sulphur fuels, and the expenses (pressure, reactor size, investment costs, energy consumption, specific active catalysts) are high to meet future requirements. alternative processes, which are not limited to hydrotreating, are therefore desirable. Beside an overview about hydrotreating, this paper presents two quite different alternatives: Extraction of sulphur compounds by ionic liquids and the synthetic production of S-free fuels from natural gas by Fischer-Tropsch-synthesis. Ionic liquids (ILs) are low melting (<100°C) salts which represent a new class of non-molecular, ionic solvents. In the experiments presented, extraction of model diesel oils (dibenzothiophene and dodecanthiol in n-dodecane) as well as of a real predesulphurized diesel oil (with about 400 ppm S) were investigated. The results show the excellent and selective extraction properties of ILs for organic sulphur compounds, especially with regard to those compounds which are very difficult to remove by common hydrodesulphurization. As expected, the desulphurization by extraction is much more complicated in case of real diesel oil (compared to a model oil) due to its complex chemical composition including many different sulphur compounds and other impurities like organic nitrogen and metal-compounds. Nevertheless, the results with pre-desulphurized diesel oil are also very promising. So, extraction of sulphur components by ILs is a new approach for deep desulphurization of diesel oil. The application of very mild process conditions (low pressure and temperature) in comparison to traditional hydrotreating is an additional advantage of this new concept. An alternative to today’s fuels based on crude oil is the production of gasoline and diesel oil from natural gas (or other fossil fuels like coal) by Fischer-Tropsch-synthesis (FTS). The products like diesel oil are completely free of sulphur and other impurities like nitrogen and metal compounds. Although several FTS-processes have been investigated and developed, and some processes are already running on a technical scale, a real breakthrough was not obtained up to now. The production costs of these capital-intensive processes are probably above the breakeven point, at least at today’s oil price. In this paper, a ‘lowcost’ process is discussed, which is based on nitrogen-rich syngas. In contrast to classical FTS-processes with nitrogen-free syngas, the investment costs are probably lower: The syngas is produced by partial oxidation with ait, which eliminates the need of an air separation plant, while a process with nitrogen-rich syngas does not utilize a recycle loop and a recycle compressor.  相似文献   

18.
目前医患关系现状及对策研究   总被引:1,自引:0,他引:1  
医患关系是社会关系的组成部分,医患关系是医疗实践活动中最基本的人际关系,良好的医患沟通是实现以病人为中心,促进社会和谐的基础.医患关系作为一种最基本的社会关系,已普遍受到人们的关注,它随着医学模式的发展,不断发生新的变化.目前我国经济正沿着市场化的轨迹发展,医疗制度改革也在深入进行,这对构建和谐医患关系提出了新的挑战和考验,要想构建和谐的医患关系,必须医方、患方、社会三者共同努力,国家增加卫生投资力度,准确定位医疗机构的性质,确保广大中低档人群的基本健康等实际问题已摆在我们面前,只有从根本上解决群众“看病难、看病贵”的问题,才能实现医患关系真正意义上的融洽.同时我们还要看到,理想化的期待与非理想化的现实差距是客观存在,融洽医患关系是一个漫长的过程,需要我们在健全法制的同时提高自律的约束,只有以诚信为杠杆、人文为基石,才能真正实现理想状态下的医患关系,即充满同情心的医生和对医生充满信任的病人.参8.  相似文献   

19.
The recent dispute over the impact of economic growth on the environment relative to the (predicted) physical limits imposed by the ecological system hinges on the role of pollution-preventive technology. This paper attempts a cost-effectiveness evaluation of alternative methods of preventing the largest source of marine oil pollution. The first major result of the analysis is that the technology which minimizes internal costs (and is favored by the oil companies) does not minimize the social costs of pollution prevention. The second is that relative to the price of oil the cost of pollution-prevention processes is very small indeed.  相似文献   

20.
Clark RM  Anderson KE  Gadau J  Fewell JH 《Ecology》2006,87(9):2201-2206
The fate of a social insect colony is partially determined by its ability to allocate individuals to the caste most appropriate for the requirements for growth, maintenance, and reproduction. In pairs of dependent lineages of Pogonomyrmex barbatus, the allocation of individuals to the queen or worker caste is constrained by genotype, a system known as genetic caste determination (GCD). In mature GCD colonies, interlineage female eggs develop into sterile workers, while intralineage eggs become reproductively capable queens. Although the population-level consequences of this system have been intensively studied, the proximate mechanisms for GCD remain unknown. To elucidate these mechanisms, we brought newly mated queens into the laboratory and allowed them to establish colonies, nearly half of which unexpectedly produced virgin queens only seven months after colony founding. We genotyped eggs, workers, and the virgin queens from these colonies. Our results showed that queens in young colonies produce both interlineage and intralineage eggs, demonstrating that queens of GCD colonies indiscriminately use sperm of at least two lineages to fertilize their eggs. Intralineage eggs were more frequent in colonies producing virgin queens. These findings suggest that intralineage eggs are predetermined to become queens and that workers may cull these eggs when colonies are not producing queens. Virgin queens produced by young GCD colonies were smaller than field-caught virgin queens, and often had developmental problems. Hence, they are probably nonfunctional and represent an intense resource drain for developing colonies, not a contribution to colony fitness.  相似文献   

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