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Clara Sangrós Giménez Laura Helmers Carsten Schilde Alexander Diener Arno Kwade 《化学工程与技术》2020,43(5):819-829
All-solid-state batteries constitute a very promising energy storage device. Two very important properties of these battery cells are the ionic and the electrical conductivity, which describe the ion and the electron transport through the electrodes, respectively. In this work, a numerical method is presented to model the electrical conductivity, considering the outcome of discrete-element method simulations and the intrinsic conductivities of both the active material particles and the conductive additive particles. The results are calibrated and validated with the help of experimental data of real manufactured electrodes. The tortuosity, which strongly influences the ionic conductivity, is also presented for the analyzed electrodes, taking their microstructure into account. 相似文献
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The influence of soluble organic matter from municipal solid waste compost on trace metal leaching in calcareous soils 总被引:8,自引:0,他引:8
The use of municipal solid waste (MSW) compost as fertilizer may cause increased leaching due to its high content of trace metals and thus pose a threat to groundwater quality. The effect of MSW compost application on trace metal leaching in calcareous soils has been studied in soil column experiments under laboratory conditions using three soils from the study area in the Gaza Strip and Israel. Higher levels of organic matter in solution (TOMS), nitrate, and the trace metals Cu, Ni and Zn were found in the leachates of a sandy soil and, to a lesser extent, a loamy soil, to which MSW compost had been applied at a rate of 65 Mg ha(-1) (dry weight basis). Nevertheless, the majority of water-soluble trace metal species from compost accumulated in the topsoil rather than washing out, with the exception of aqueous Ni species. Ni concentrations exceeded the maximum allowable limits for drinking water (in Germany: 50 microg l(-1)) at peak times in the leachates from sandy soil, while all other trace metals remained far below the corresponding limits. The highest absolute concentrations of trace metals were found for the leaching of Cu from compost-amended sandy soil (100 microg l(-1)). For Cd, Pb and Hg no evidence of downward movement was found in any assay. Gel filtration studies of the collected soil leachates showed that all trace metals encountered in the leachates existed mostly as organic complexes. In sandy soil most of the water-soluble organic matter added with the compost had leached from the rootzone after a year's equivalent of rainfall, while TOMS mobility was greatly reduced in the loamy soil. The makeup of the TOMS in the sandy soil and its metal-binding capacity was strongly influenced by compost-derived dissolved organic matter (DOM) as observed by FTIR spectrometry. Hence the vertical displacement of trace metals (Cu, Ni, Zn) in these calcareous soils seemed to result primarily from the presence of mobile metal-organic complexes in the soil solution after compost addition. Further studies are required to validate these findings in the field, especially to assess the risk of Cu and Ni leaching in sandy soil. 相似文献
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风景园林学科在德国已有悠久的发展历史。早期“古典主义”的大部分作品保留完好,如文艺复兴时期巴洛克、洛可可式公园,其中有些甚至是联合国教科文组织世界遗产。80多年前,在德国大学中已经创建了风景园林专业这门学科。今天共有16所大学,技术学院或应用科学大学,都设有风景园林、风景园林设计和风景园林规划专业。自1954年开始,德国风景园林师协会(BDLA)作为国际风景园林师联合会(IFLA)的成员国,一直享有很高的声誉。1977年德国风景园林师协会设立“德国风景园林奖”。该奖项每两年由选出的独立评委会从德国近五年内杰出的项目评出两个大奖和八个荣誉奖。得奖的作品都具有很高的社会和生态价值,同时在美学上是令人信服和创新的。本文介绍了获得2003年和2005年德国风景园林奖的各个作品。它们是德国风景园林设计和规划领域目前最好的实例,从而很好地反映了德国风景园林行业现在的工作领域。 相似文献
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Arno J. Van der Vlist Marien H. Vrolijk Geert P.M.R. Dewulf 《Construction Management & Economics》2014,32(6):641-651
The interplay between information and communication technology (ICT) and the competitiveness of construction firms is considered. More specifically, the question is whether firms that invest in information and communication technology have a production cost advantage. The economics literature hypothesizes that ICT brings about a production cost advantage, as ICT brings flexibility and improves the planning, organization and control of work. To test this proposition for the construction industry, a production cost function allowing for the inclusion of ICT is formulated. Using statistical nearest-neighbour matching methods it is possible to identify the effect of ICT on production costs thereby controlling for economic moderators. Data from a sample of Dutch construction firms reveal that those firms that installed ICT capital do have a production cost advantage. The results indicate further that firms need a minimum level of ICT capital to fully benefit from its production cost advantage. 相似文献
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Porous magnesium has a great potential to be used as degradable bone scaffolds. In this study, porous magnesium with 35% percolating porosity has been successfully fabricated through powder metallurgy route utilizing space holders. The intrinsic mechanical properties of the porous magnesium were measured by nanoindentation testing and analyzed with the Oliver–Pharr method. Afterward, a ceramic coating on the surface of the porous magnesium was performed by plasma electrolytic oxidation (PEO) treatment in a silicate‐based solution. The morphology and composition results of the PEO coatings indicated that it is possible to apply a homogenous and adhesive ceramic coating layer on all free surface of the porous magnesium through PEO method. The protective performance of the PEO coatings was evaluated using by potentiodynamic polarization and electrochemical impedance spectroscopy tests in simulated body fluid. The results revealed the PEO coating significantly improves biocorrosion resistance of the porous magnesium. Therefore, it can be used as an effective method to control the degradation rate of porous magnesium implants in the human body. 相似文献
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Bill Robert Fleck Martin Troya Javier Mayerhofer Tanja Wimmer Manuel 《Software and Systems Modeling》2019,18(2):1017-1046
Software and Systems Modeling - Many model transformation scenarios require flexible execution strategies as they should produce models with the highest possible quality. At the same time,... 相似文献