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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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Javier Andrés Bocchio Mariano Martín Escobar Javier Carlos Quagliano Amado 《Polymer Engineering and Science》2020,60(3):630-635
Ablation resistance and mechanical properties of polyurethane-based composites containing different amounts (up to 5 wt%) of organoclay were correlated with the morphological characterization. The crosslinking density of the polyurethane increased with the amount of organoclay. At low concentration (up to 1 wt%), the organoclay was well exfoliated, while at higher concentration, both exfoliated and intercalated platelets were found. A linear correlation was observed between the tensile test and the concentration of organoclay. Erosion velocity decreased 40% with the incorporation of 5% of organoclay. POLYM. ENG. SCI., 60:630–635, 2020. © 2020 Society of Plastics Engineers 相似文献
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Carlos R. Arza Patric Jannasch Peter Johansson Per Magnusson Alan Werker Frans H. J. Maurer 《应用聚合物科学杂志》2015,132(15)
Thermal degradation of poly[(R)−3‐hydroxybutyric acid] (PHB) during melt mixing results in random chain scission that produces shorter polymer chains containing crotonic and carboxyl end groups. One way of preventing this serious reduction of molar mass is to add agents that react with at least two of the newly generated end groups. Different types of commercially available additives known to react with carboxyl group, namely bis(3,4‐epoxycyclohexylmethyl) adipate (BECMA), 2,2'‐bis(2‐oxazoline) (BOX), trimethylolpropane tris(2‐methyl‐1‐aziridinepropionate) (PETAP), triphenyl phosphate (TPP), tris(nonylphenyl) phosphate (TNPP), polycarbodiimide (PCDI), and poly(methyl metharylate‐co‐glycidyl methacrylate) (GMA.MMA) were mixed with PHB by cocasting from solution in chloroform. Dynamic rheology as well as measurements of molar masses before and after dynamic analysis was used to evaluate the effect of the additives on the melt stability of PHB. Measurements of the dynamic shear modulus and the molar mass of molten PHB with the additives PCDI and GMA.MMA showed a minor improvement on the thermal stability. Furthermore, TPP and TNPP did not affect the thermal stability of PHB, whereas the presence of BECMA, BOX, and PETAP gave a strong decrease of the dynamic modulus compared with neat PHB. © 2014 The Authors Journal of Applied Polymer Science Published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41836. 相似文献
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