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591.
The term ‘sustainable development’ is defined and discussed with regard to its significance and its application in the field of chemistry. This is presented using the synthetic organic chemistry as an example. A review of the history of chemistry indicates clearly the necessity for further developments in the course of concepts involving sustainability. Following the eras of bituminous coal tar and mineral oil in both of the two past centuries, a search for new raw materials and a reduction in the global ecotoxicological potential for danger is being strived for. Critical contemplations are mandatory in order to avoid making this term ‘persistence’ into a keyword. Consequently, one must take into consideration the field of research and development as well as reflecting about the classification of chemical and scientific research projects, and their political as well as social relationships. Aside from the new methods of synthesis, this will also require the formulation of other decision-relevant criteria. 相似文献
592.
Werner Brack Michaela Hein Stefan Jansen und Peter von der Ohe 《Umweltwissenschaften und Schadstoff-Forschung》2007,19(3):A6
Ohne Zusammenfassung 相似文献
593.
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595.
Early detection and identification of dangerous states in chemical plants using neural networks 总被引:1,自引:0,他引:1
Joachim Neumann Grge Deerberg Stefan Schlüter 《Journal of Loss Prevention in the Process Industries》1999,12(6):297-453
The suitability of pattern recognition for safety diagnosis of chemical plants will be discussed. Therefore, experiments in a miniplant and with a process simulator are carried out. The process characteristics are treated with different recognition methods and classified with the aid of expert know how. Afterwards, the trained system can be used for process diagnosis. The capability of neural networks for this problem could be shown. 相似文献
596.
This paper is concerned with the implications of climate change, and government policies to address it, for countries’ fiscal systems at the national level. Given the uncertainties associated with climate change and countries’ responses to it, the article can do no more than review and suggest some of the major issues of likely importance for fiscal sustainability and how they might be addressed. First the paper defines fiscal sustainability and addresses some general issues related to countries’ attempts to adapt to or mitigate climate change. It then works through a number of more specific issues, discussing policies such as the implementation of environmental taxes or other instruments for the mitigation of climate change. The assessment of the impacts of such policies on fiscal sustainability requires the application of sophisticated economic models, and the paper briefly explores the relative advantages of different modeling approaches in relation to the assessment of fiscal sustainability under policies to mitigate climate change. The major research need identified by the paper is for the development of macroeconomic models that will enable countries identify the wider effects of environmental taxes and help them undertake multi-year budgeting processes. 相似文献
597.
Stefan Seitz 《Disasters》1998,22(1):76-90
The particular problems arising in the aftermath of natural disasters in indigenous societies in the Third World, especially in ethnic or cultural minorities, have until now received only little attention in social scientific research. The potential of such indigenous groups to use their traditional knowledge and behaviour patterns in coping with natural disasters has been badly neglected. The example of the Aeta in Zambales, Philippines, a marginal group who were hit directly by the eruption of Mt Pinatubo in 1991, shows how traditional economic and social behaviour can in some measure determine their various survival strategies. 相似文献
598.
Background
Natural gas makes a significant contribution to the current energy supply and its importance, in relation to both the German and worldwide energy supplies, will increase further in decades to come. In addition to its high degree of efficiency, the low level of direct GHG combustion emissions is also an advantageous factor. However, around 90% of natural gas is methane (CH4), which is the second most significant GHG due to its high greenhouse potential (21 times higher than CO2). Therefore, high levels of direct gas losses of natural gas in its production, processing, transport and distribution could neutralise its low emission advantages. This is particularly apparent when considering the growing distances between production and use, the demanding production processes and the upcoming worldwide market for LNG (liquefied natural gas).Aim
This paper aims to analyse and illustrate the future GHG emissions of the whole process chain of natural gas (indirect emissions) to be supplied to the German border over the next 2 decades. This should allow the comparison of total GHG emissions (indirect and direct) of natural gas with the GHG emissions of other fossil fuels. By considering likely changes in gas origin as well as dynamic changes in the infrastructure and technology of gas production, processing and transport until 2030, all relevant factors are included. The study focuses on the emissions of Russian natural gas as Russia is already, and will be in the future, the most important gas supplier to the German and European gas markets.Results and Discussion
The analysis illustrates a significant change in the gas supply over the next two decades. The EU Gas Fields are in decline and it is predicted that these will run dry. In parallel the share of Russian and Norwegian natural gas, and also the levels of LNG production (e.g. from Algeria or Egypt), will increase. Although the potential for GHG emissions tends to grow as a result of greater transport distances and demanding production and processing activities, high investment in necessary mitigation options (e.g. through replacing older and inefficient technology; updating to state-of-the-art technology) may neutralise the increase. The overall result of these counteracting trends will be to decrease GHG emissions, in a range of around 12% per TJ of direct emissions of natural gas, depending on the level of investment in the modernisation of the Russian gas infrastructure and the improvements of the LNG process. In the two given scenarios the indirect emissions of the natural gas used in Germany will decrease from about 23 million t CO2-eq (2005) to 19.5 or 17.6 million t CO2-eq in the year 2030. In spite of a significant higher gas consumption the emissions are reduced in the first scenario due to technical modifications. In the second scenario the emission reduction is based on the lower gas consumption.Conclusions
At present, the indirect GHG emissions of the natural gas process chain are comparable to the indirect emissions produced by oil and coal. The emission trend of the natural gas process chain will markedly decrease if the mitigation options are followed consistently. However, in order to ensure the long-term security of natural gas supply for future decades, a high level of investment is essential. With regard to future emissions, the best available technology and, therefore, that which is most economically feasible in the long term, should be used. Under these conditions natural gas — as the fossil fuel with the lowest levels of GHG emissions — can play a major role in the transition to a renewable energy supply for the future. 相似文献599.
600.
A multi-scale examination of stopover habitat use by birds 总被引:1,自引:0,他引:1
Most of our understanding of habitat use by migrating land birds comes from studies conducted at single, small spatial scales, which may overemphasize the importance of intrinsic habitat factors, such as food availability, in shaping migrant distributions. We believe that a multi-scale approach is essential to assess the influence of factors that control en route habitat use. We determined the relative importance of eight variables, each operating at a habitat-patch, landscape, or regional spatial scale, in explaining the differential use of hardwood forests by Nearctic-Neotropical land birds during migration. We estimated bird densities through transect surveys at sites near the Mississippi coast during spring and autumn migration within landscapes with variable amounts of hardwood forest cover. At a regional scale, migrant density increased with proximity to the coast, which was of moderate importance in explaining bird densities, probably due to constraints imposed on migrants when negotiating the Gulf of Mexico. The amount of hardwood forest cover at a landscape scale was positively correlated with arthropod abundance and had the greatest importance in explaining densities of all migrants, as a group, during spring, and of insectivorous migrants during autumn. Among landscape scales ranging from 500 m to 10 km radius, the densities of migrants were, on average, most strongly and positively related to the amount of hardwood forest cover within a 5 km radius. We suggest that hardwood forest cover at this scale may be an indicator of habitat quality that migrants use as a cue when landing at the end of a migratory flight. At the patch scale, direct measures of arthropod abundance and plant community composition were also important in explaining migrant densities, whereas habitat structure was of little importance. The relative amount of fleshy-fruited trees was positively related and was the most important variable explaining frugivorous migrant density during autumn. Although constraints extrinsic to habitat had a moderate role in explaining migrant distributions, our results are consistent with the view that food availability is the ultimate factor shaping the distributions of birds during stopover. 相似文献