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1.
Senanu Samuel Wang Zhaohui Ratvik Arne Petter Grande Tor 《JOM Journal of the Minerals, Metals and Materials Society》2020,72(1):210-217
JOM - Autopsies of six spent potlinings with different carbon cathode block grades, amperage regimes and cell designs were conducted at three separate smelters to reveal possible mechanisms causing... 相似文献
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Juan Carlos Fortes Jos Miguel Dvila Aguasanta Miguel Sarmiento Ana Teresa Lus Mara Santisteban Jess Daz-Curie Francisco Crdoba Jos Antonio Grande 《Mine Water and the Environment》2020,39(2):195-203
Mining equipment and structural elements (e.g. bridges, mining exploration equipment), which are mainly made of steel and concrete, undergo corrosion processes that are strongly accelerated in these extremely acidic environments, with the further aid of acidophilic bacteria that act as catalysts. 相似文献
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Nikola Kanas Sathya Prakash Singh Magnus Rotan Mohsin Saleemi Michael Bittner Armin Feldhoff Truls Norby Kjell Wiik Tor Grande Mari-Ann Einarsrud 《Journal of the European Ceramic Society》2018,38(4):1592-1599
Due to high figure of merit, Ca3Co4 ? xO9 + δ (CCO) has potential as p-type material for high-temperature thermoelectrics. Here, the influence of processing including solid state sintering, spark plasma sintering and post-calcination on stability, microstructure and thermoelectric properties is reported. By a new post-calcination approach, single-phase materials were obtained from precursors to final dense ceramics in one step. The highest zT of 0.11 was recorded at 800 °C for CCO with 98 and 72% relative densities. In situ high-temperature X-ray diffraction in air and oxygen revealed a higher stability of CCO in oxygen (~970 °C) than in air (~930 °C), with formation of Ca3Co2O6 which also showed high stability in oxygen, even at 1125 °C. Since achievement of phase pure high density CCO by post-calcination method in air is challenging, the phase stability of CCO in oxygen is important for understanding and further improvement of the method. 相似文献
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Silvia Grande Joachim Van Guyse Anton Y. Nikiforov Iuliia Onyshchenko Mahtab Asadian Rino Morent Richard Hoogenboom Nathalie De Geyter 《应用聚合物科学杂志》2020,137(30):48914
In previous work, an atmospheric pressure plasma jet was applied to successfully improve the electrospinnability of poly-ε-caprolactone (PCL) which enabled the fabrication of beadless nanofibers. In this paper, we report the aging effect of the plasma treatment to evaluate the robustness of the developed process. For this purpose, plasma-treated PCL polymer solutions with different exposure time were stored for 1 and 8 days and the aged solutions were analyzed in terms of conductivity, viscosity, surface tension, pH, and polymer molecular weight. During storage, the surface tension and acidity of the plasma-treated solutions were maintained constant. However, the viscosity was found to be significantly lower after 8 days which was attributed to PCL degradation. Electrospinning of all stored PCL solutions resulted in the generation of beadless PCL nanofibers. The plasma treatment effects were thus found to be highly stable over time and capable of producing high-quality PCL nanofibers up to 8 days. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48914. 相似文献
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Bertanza G Pedrazzani R Dal Grande M Papa M Zambarda V Montani C Steimberg N Mazzoleni G Di Lorenzo D 《Water research》2011,45(8):2473-2484
A major source of the wide presence of EDCs (Endocrine Disrupting Compounds) in water bodies is represented by direct/indirect discharge of sewage. Recent scientific literature reports data about their trace concentration in water, sediments and aquatic organisms, as well as removal efficiencies of different wastewater treatment schemes. Despite the availability of a huge amount of data, some doubts still persist due to the difficulty in evaluating synergistic effects of trace pollutants in complex matrices. In this paper, an integrated assessment procedure was used, based on chemical and biological analyses, in order to compare the performance of two full scale biological wastewater treatment plants (either equipped with conventional settling tanks or with an ultrafiltration membrane unit) and tertiary ozonation (pilot scale).Nonylphenol and bisphenol A were chosen as model EDCs, together with the parent compounds mono- and di-ethoxylated nonylphenol (quantified by means of GC-MS). Water estrogenic activity was evaluated by applying the human breast cancer MCF-7 based reporter gene assay. Process parameters (e.g., sludge age, temperature) and conventional pollutants (e.g., COD, suspended solids) were also measured during monitoring campaigns.Conventional activated sludge achieved satisfactory removal of both analytes and estrogenicity. A further reduction of biological activity was exerted by MBR (Membrane Biological Reactor) as well as ozonation; the latter contributed also to decrease EDC concentrations. 相似文献
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Annika K. E. Andersson Sverre M. Selbach Christopher S. Knee Tor Grande 《Journal of the American Ceramic Society》2014,97(8):2654-2661
The crystal structures of proton‐conducting BaZr1?xYxO3?x/2 (BZY05–BZY20) and BaCe0.8Y0.2O2.9 (BCY20) during hydration/dehydration has been studied by in situ high‐temperature X‐ray diffraction and thermal analysis. A contraction/expansion of the crystal lattice associated with dehydration/hydration was observed for all materials at elevated temperatures and the polymorphic phase transition temperatures of BaCe0.8Y0.2O2.9 were depressed by lowering the vapor pressure of water. A thermodynamic formalism is introduced to describe the chemical expansion associated with the hydration of oxygen vacancies in acceptor‐doped oxides. A conventional point defect model was applied to describe the lattice strain associated with the hydration. The chemical expansion is discussed with respect to the available volumetric data on the hydration of proton‐conducting oxide materials and its likely impact on ceramic fuel cells/hydrogen separation membranes utilizing a proton‐conducting electrolyte. 相似文献
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