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Goal and Scope
Which impact does the use of non-energetic abiotic resources (ores, minerals, etc.) have in life cycles of energy systems based on biogenic and fossil fuels? Is this kind of resource use less or more environmentally harmful than the utilisation of energetic abiotic resources (mineral oil, natural gas, etc.) in the same life cycles? This paper aims at answering these questions. In Part 1, a methodology is presented and applied to the life cycles of selected energy systems. Part 2 presents and discusses the results.Method
This study looks at the complete life cycles of selected energy systems. The methodology used bases on the state-of-the-art of life cycle assessment (LCA) methodology. For the assessment of energetic abiotic resource use, a widely recognised method can be used. For the assessment of non-energetic abiotic resource use, no overall recognised methodological approach exists. That is why for this aspect two different methods are exemplarily applied and compared with each other.Results and Conclusion
Results will be presented and discussed in Part 2.Recommendation and Perspective
Recommendation and conclusions will be derived from study results in Part 2. 相似文献83.
Aluminium ions hydrolyse and polymerise into different species in water. Main aluminium species in aluminium coagulant solutions are monomeric Al species (Al1) and polymeric Al species Al13O4(OH)24(7+) (Al13). The aluminium species distribution in coagulant solutions can be influenced by many parameters. This paper studies influences of concentrations of total aluminium species (Al(t)) and other species--OH-, polysilicic acid and ferric species, which were added in aluminium coagulant solutions, on the aluminium species distribution through 27Al nuclear magnetic resonance (NMR) analysis. Results show that only Al1 and no Al13 exist in coagulant solutions at higher Al(t) concentrations (over 1 mol l(-1)), while both species exist at lower Al(t) concentrations (0.1 mol l(-1)). The increase of OH/Al value (molar ratio) increases the concentration of Al13 in coagulant solutions, while the addition of polysilicic acid and ferric species decreases the concentration of Al13. 相似文献
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Hermann Kühn 《Die Naturwissenschaften》1983,70(9):421-429
Stylistic criteria are sometimes not sufficient in order to differentiate with certainty between copies or fakes and originals. Analyses of paints, supports and artistic technique may give an indication for the earliest possible date of a painting or a work of graphic arts. For example, supports made from oak, fir, spruce and beech can be dated by yearring analysis (dendrochronology). Exclusively methods on micro and ultramicro scale are suitable for the identification of various materials, i.e. microchemistry, emission spectrographic analysis, X-ray powder diffraction because only very tiny samples can be taken from the object. 相似文献
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Assessing environmental performance by combining life cycle assessment, multi-criteria analysis and environmental performance indicators 总被引:1,自引:0,他引:1
We present a new analytical tool, called COMPLIMENT, which can be used to provide detailed information on the overall environmental impact of a business. COMPLIMENT integrates parts of tools such as life cycle assessment, multi-criteria analysis and environmental performance indicators. It avoids disadvantages and combines complementary aspects of these three tools. The methodology is based on environmental performance indicators, expanding the scope of data collection towards a life cycle approach and including a weighting and aggregation step. A case study on the Thai pulp industry illustrates the usefulness of COMPLIMENT. 相似文献
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