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21.
Within the emerging concept of industrial ecology (IE) that belongs to the research and practical field of sustainable development (SD), the natural ecosystem evolution over time has been described as a metaphor that presents systems of type I, type II and type III ecology. Type I describes a situation when there was little life on earth and plenty of resources. In type II, the ecosystem starts to develop material cycles and energy cascades between organisms and species due to increasing amount of life and emerging scarcity of resources. In type III, the mature ecosystem stage, the system actors have developed nearly completely cyclic flows of matter, energy cascades and diverse interdependencies between them. This paper uses the metaphor in the three systems to develop practical models of type I, II and III industrial ecosystems for an economic system of heating energy and its evolution over time. First, the physical flows of matter and energy are described by using two contrasting case system characteristics, 'throughput' and 'roundput'. Throughput means linear material and energy flows. Roundput means material cycles, energy cascades and sustainable use of renewables, i.e., ecosystem type III. Second, the more structural and organisational features are considered with the characteristic of 'diversity' meaning diversity in resources, human involvement and economic actors and technology used. The case system development over time shown with our practical model of type I–III is radically different from the ecosystem evolution as described in the literature on the industrial ecosystem metaphor of type I–III. This conclusion as a research result, however, is tentative, because of the fuzzy and vague meaning assigned to a metaphor and its confusion with a practical model of industrial development in the industrial ecology literature.  相似文献   
22.
The development of the practical side of the concept of industrial ecology has taken two different but interrelated paths during the last two decades: the product-based systems perspective; and the geographically defined local-regional industrial ecosystem approach. Both approaches focus on material and energy flows aiming at reducing the industrial system's virgin resource use and waste and emission outputs. The ideal has arisen to mimic the model of a sustainable natural ecosystem, which relies solely on solar energy as the input and creates cyclical flows of materials (and related energy cascades) between organisms and in the food chain. It is argued in the industrial ecology literature that wastes, as defined in human industrial system terms, are non-existent in the natural recycling system. In this paper, an application of the product-based systems approach is given with paper life cycles and a basic life cycle inventory model. An application to the regional approach is presented in the regional energy supply system of the city of Jyväskylä in Finland. The paper aims at discussing the two approaches in industrial ecology and considers their contradictory characteristics as well as their similarities. When the basic vision and the overriding goal is the local industrial ecosystem, the product-based approach can serve as an inventory tool to support the project. In this situation, the two approaches would seem to be each other's complement. When the two approaches are adopted as each other's substitute, they may support conflicting decisions for environmental policy and management. This may create difficulties in the implementation of industrial ecology. On the basis of both of the approaches to industrial ecology, the external environment of an organization is considered to comprise the societal material and energy flow environment and the natural material and energy flow environment .  相似文献   
23.
Quantitative estimates of future climate change and its various impacts are often based on complex climate models which incorporate a number of physical processes. As these models continue to become more sophisticated, it is commonly assumed that the latest generation of climate models will provide us with better estimates of climate change. Here, we quantify the uncertainty in future climate change projections using two multi-model ensembles of climate model simulations and divide it into different components: internal, scenario and model. The contributions of these sources of uncertainty changes as a function of variable, temporal and spatial scale and especially lead time in the future. In the new models, uncertainty intervals for each of the components have increased. For temperature, importance of scenario uncertainty is the largest over low latitudes and increases nonlinearly after the mid-century. It has a small importance for precipitation simulations on all time scales, which hampers estimating the effect which any mitigation efforts might have. In line with current state-of-the-art adaptation approaches, we argue that despite these uncertainties climate models can provide useful information to support adaptation decision-making. Moreover, adaptation decisions should not be postponed in the hope that future improved scientific understanding will result in more accurate predictions of future climate change. Such simulations might not become available. On the contrary, while planning adaptation initiatives, a rational framework for decision-making under uncertainty should be employed. We suggest that there is an urgent need for continued development and use of improved risk analysis methods for climate change adaptation.  相似文献   
24.
Planning for adaptation to climate change is often regarded to be a local imperative and considered to be more effective if grounded on a solid evidence base and recognisant of relevant climate projections. Research has already documented some of the challenges of making climate information usable in decision-making but has not yet sufficiently reflected on the role of the wider institutional and regulatory context. This article examines the impact of the external institutional context on the use and usability of climate projections in local government through an analysis of 44 planning and climate change (adaptation) documents and 54 semi-structured interviews with planners in England and Germany conducted between July 2013 and May 2014. We show that there is little demand for climate projections in local adaptation planning in either country due to existing policy, legal and regulatory frameworks. Local government in England has not only experienced a decline in use of climate projections, but also the waning of the climate change adaptation agenda more widely, amidst changes in the planning and regulatory framework and severe budget cuts. In Germany, spatial planning makes substantial use of past and present climate data, but the strictly regulated nature of planning prevents the use of climate projections, due to their inherent uncertainties. Findings from the two countries highlight that if we are to better understand the usability of climate projections, we need to be more aware of the institutional context within which planning decisions are made. Otherwise we run the risk of continuing to provide tools and information that are of limited use within their intended context.  相似文献   
25.
Formaldehyde has been classified in group 1 as a potential source of human carcinogen by the International Agency for Research on Cancer. In this study, we evaluated the DNA damage in workers who were occupationally exposed to formaldehyde during the manufacture of melamine dinnerware.

Age, sex, smoking habits, and socioeconomic status were matched by the controls (n = 34) of workers not occupationally exposed to formaldehyde. The median value of formaldehyde time weighted average exposure in three workshops was 0.086 mg/m3. No significant difference was observed between sex and smoking habit in the assessed workers. Alkaline comet assay of peripheral blood lymphocytes was used to determine the DNA damage in the subjects. Olive moment was significantly higher in the exposed group compared with the control group.

Overall, the results suggest that respiratory exposure to low concentrations of formaldehyde causes DNA damage in peripheral blood lymphocyte. Therefore, exposure to formaldehyde should be reduced to the lowest possible level.  相似文献   

26.
Flue gas emissions of wood and heavy fuel oil (HFO) fired district heating units of size range 4–15 MW were studied. The emission measurements included analyses of particle mass, number and size distributions, particle chemical compositions and gaseous emissions. Thermodynamic equilibrium calculations were carried out to interpret the experimental findings.In wood combustion, PM1 (fine particle emission) was mainly formed of K, S and Cl, released from the fuel. In addition PM1 contained small amounts of organic material, CO3, Na and different metals of which Zn was the most abundant. The fine particles from HFO combustion contained varying transient metals and Na that originate from the fuel, sulphuric acid, elemental carbon (soot) and organic material. The majority of particles were formed at high temperature (>800 °C) from V, Ni, Fe and Na. At the flue gas dew point (125 °C in undiluted flue gas) sulphuric acid condensed forming a liquid layer on the particles. This increases the PM1 substantially and may lead to partial dissolution of the metallic cores.Wood-fired grate boilers had 6–21-fold PM1 and 2–23-fold total suspended particle (TSP) concentrations upstream of the particle filters when compared to those of HFO-fired boilers. However, the use of single field electrostatic precipitators (ESP) in wood-fired grate boilers decreased particle emissions to same level or even lower as in HFO combustion. On the other hand, particles released from the HFO boilers were clearly smaller and higher in number concentration than those of wood boilers with ESPs. In addition, in contrast to wood combustion, HFO boilers produce notable SO2 emissions that contribute to secondary particle formation in the atmosphere. Due to vast differences in concentrations of gaseous and particle emissions and in the physical and chemical properties of the particles, HFO and wood fuel based energy production units are likely to have very different effects on health and climate.  相似文献   
27.
The intake fraction (iF) has been defined as the integrated incremental intake of a pollutant released from a source category or region summed over all exposed individuals. In this study we evaluated the iFs in the population of Europe for emissions of anthropogenic primary fine particulate matter (PM2.5) from sources in Europe, with a more detailed analysis of the iF from Finnish sources. Parameters for calculating the iFs include the emission strengths, the predicted atmospheric concentrations, European population data, and the average breathing rate per person. Emissions for the whole of Europe and Finland were based on the inventories of the European Monitoring and Evaluation Programme (EMEP) and the Finnish Regional Emission Scenario (FRES) model, respectively. The atmospheric dispersion of primary PM2.5 was computed using the regional-scale dispersion model SILAM. The iFs from Finnish sources were also computed separately for six emission source categories. The iFs corresponding to the primary PM2.5 emissions from the European countries for the whole population of Europe were generally highest for the densely populated Western European countries, second highest for the Eastern and Southern European countries, and lowest for the Northern European and Baltic countries. For the entire European population, the iF values varied from the lowest value of 0.31 per million for emissions from Cyprus, to the highest value of 4.42 per million for emissions from Belgium. These results depend on the regional distribution of the population and the prevailing long-term meteorological conditions. Regarding Finnish primary PM2.5 emissions, the iF was highest for traffic emissions (0.68 per million) and lowest for major power plant emissions (0.50 per million). The results provide new information that can be used to find the most cost-efficient emission abatement strategies and policies.  相似文献   
28.
尽管外部营养盐的输入量下降了约30%,但在芬兰湾的开阔海区并没有出现相应的改善.20世纪90年代末向芬兰湾中的氮排放量达到了每年120 000r,而每年磷的排放量为7000t.就其表面水域而言,芬兰湾海区营养盐的单位面积排放量是整个波罗的海营养盐平均单位面积排放量的2~3倍.尽管排放量有所下降,但在20世纪90年代中期海表和近海底的水域中磷酸盐的浓度仍呈上升趋势.导致这种状况发生的主要原因可能是20世纪90年代芬兰湾东部海域沉积物与水的交界处氧气状况的恶化导致了内部营养盐排放的增多,但20世纪80年代和90年代初期这一海区的供氧状况相对较好.根据在芬兰湾近海获取的实验数据,表层沉积物和水之间的磷酸盐-磷的通量已减少到平均值,13kg/km2-@d.这与在波兰湾开阔海区测量到的能够代表其变化趋势的磷含量相符.沉积物流出物中氮和磷的低比率在一定程度上解释了芬兰湾的初级生产中氮受到的限制.  相似文献   
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