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51.
In this paper, we suggest that the Montreal School (TMS) tradition of organizational communication offers a fruitful analytical framework that allows us to better take into account the way people practically deal with plurilingual situations as they go on with their daily activities and contribute to shaping their organizations. We identify six core features of TMS and show their analytical power in studying plurilingual interactions. TMS, we argue, is conceptually well equipped to reveal the ways in which multiple tongues are dealt with in everyday organizational settings and to uncover the constitutive nature of tongue‐in‐use.  相似文献   
52.
The requirement of high‐temperature calcination for titanium dioxide in (solid‐state) dye‐sensitized solar cells (DSSCs) implies challenges with respect to reduced energy consumption and the potential for flexible photovoltaic devices. Moreover, the use of dye molecules increases production costs and leads to problems related with dye bleaching. Therefore, fabrication of dye‐free hybrid solar cells at low temperature is a promising alternative for current DSSC technology. In this work the authors fabricate hierarchically structured titania thin films by combining a polystyrene‐block‐polyethylene oxide template assisted sol–gel synthesis with nano‐imprint lithography at low temperatures. The achieved films are filled with poly(3‐hexylthiophene) to form the active layer of hybrid solar cells. The surface morphology is probed via scanning electron microscopy and atomic force microscopy, and the bulk film morphology is examined with grazing incidence X‐ray scattering. Good light absorption by the active layer is proven by UV–vis spectroscopy. An enhancement in light absorption is observed and ascribed to light scattering in mesoporous titania films with imprinted superstructures. Accordingly a better photovoltaic performance is found for nano‐imprinted solar cells at various angles of light incidence.  相似文献   
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The wood of one tree each of SO2-damaged spruce and fir was analysed with regard to its anatomy and technology. The SO2 influence caused some alterations in the wood and, as a consequence, also with regard to some technological properties. No impairment in wood quality was observed.  相似文献   
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Ohne ZusammenfassungMitteilung aus dem Physiologischen Institut der Universität Marburg.  相似文献   
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As part of the ecological risk assessment associated with radionuclides in freshwater ecosystems, toxicity of waterborne uranium was recently investigated in the microcrustacean Daphnia magna over a three-generation exposure (F0, F1, and F2). Toxic effects on daphnid life history and physiology, increasing over generations, were demonstrated at the organism level under controlled laboratory conditions. These effects were modeled using an approach based on the dynamic energy budget (DEB). For each of the three successive generations, DEBtox (dynamic energy budget applied to toxicity data) models were fitted to experimental data. Lethal and sublethal DEBtox outcomes and their uncertainty were projected to the population level using population matrix techniques. To do so, we compared two modeling approaches in which experimental results from F0, F1, and F2 generations were either considered separately (F0-, F1-, and F2-based simulations) or together in the actual succession of F0, F1, and F2 generations (multi-F-based simulation). The first approach showed that considering results from F0 only (equivalent to a standard toxicity test) would lead to a severe underestimation of uranium toxicity at the population level. Results from the second approach showed that combining effects in successive generations cannot generally be simplified to the worst case among F0-, F1-, and F2-based population dynamics.  相似文献   
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