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C. Corbane G. Lemoine M. Pesaresi T. Kemper F. Sabo S. Ferri 《International journal of remote sensing》2018,39(3):842-853
This article presents an experiment in which multi-temporal interferometric coherence calculated from 6-days Sentinel-1A and Sentinel-1B image pairs and backscatter intensity σ° are jointly used for the extraction of built-up areas in the framework of the symbolic machine learning classification. The results obtained with the proposed approach confirm the enhanced capabilities of discriminating built-up areas when using coherence information in comparison to two available global human settlement layers derived: (1) from Landsat optical data and (2) from Sentinel-1 ground range detected data and based on backscatter intensity σ° only. The experiment carried out in The Netherlands Randstad area is expected to be indicative of the results obtainable for urban areas having similar structures and types of built-up. 相似文献
23.
Fabiana Piscitelli Roberto Coccurello Antonio Totaro Alessandro Leuti Giacomo Giacovazzo Roberta Verde Emanuela Rossi Michele Podaliri Vulpiani Nicola Ferri Roberto Giacominelli Stuffler Vincenzo Di Marzo Sergio Oddi Tiziana Bisogno Mauro Maccarrone 《European Journal of Lipid Science and Technology》2019,121(10)
24.
The advantages and open questions of the combination of modulation excitation spectroscopy and phase sensitive detection (PSD) with X-ray absorption spectroscopy (XAS) for the analysis of heterogeneous catalysts at work are reviewed. The characteristic spectral signatures of two different edges (Pd K and Pt L3) are described in relation to the red-ox chemistry of Pd/Al2O3 and Pt/Al2O3 with respect to NO reduction by CO and CO oxidation, respectively. Both examples demonstrate that PSD makes XAS sensitive to potentially active species for the catalytic reaction. 相似文献
25.
Nora MartinezKenji Hisada Isao TabataKazumasa Hirogaki Susumu YonezawaTeruo Hori 《The Journal of Supercritical Fluids》2011,56(3):322-329
The effect of thermal treatment to improve the metal adhesion into poly-(p-phenylene terephthalamide) (PPTA), e.g. aramid fiber, has been investigated. After palladium(II)-hexafluoroacetylacetonate metal complex, Pd(hfac)2, seeding into the fiber using supercritical fluid carbon dioxide, scCO2, a post-thermal treatment was conducted. As a result, after carrying out electroless copper plating, the adhesive strength between polymer substrate and copper layer greatly increased. Also, in order to have a better comprehension on decomposition reactions of Pd(hfac)2 under supercritical conditions, remains of metal complex were analyzed using electron ionization mass spectrometry technique (EI-MS). EI-MS mass spectra derived from Pd(hfac)2 gave us useful information about its dissociation reactions and reaction temperature under supercritical conditions. Additionally, to verify the Pd particles seeding in the fiber surface, X-ray photoelectron spectrometry (XPS) analyses were performed. The results confirmed that post-thermal treatment induced Pd particles diffusion and deeper penetration of Pd complex and its fragments into the fiber. 相似文献
26.
Silvia Patricia Galíndez‐Nájera Oswaldo Ramos‐Monroy Nora Ruiz‐Ordaz Angélica Salmerón‐Alcocer Cleotilde Juárez‐Ramírez Deifilia Ahuatzi‐Chacón Everardo Curiel‐Quesada Juvencio Galíndez‐Mayer 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(4):554-561
BACKGROUND: The impact of mixtures of chloro‐triazinic herbicides, such as atrazine and simazine, on aquatic ecosystems is of environmental concern. To study their biodegradation under various operational conditions, a binary community comprising Stenotrophomonas maltophilia and Arthrobacter sp. attached to the porous support of a packed bed reactor, was evaluated. RESULTS: The genetic analysis of the two atrazine‐degrading strains revealed that genes atzA, atzB, atzC are present in both bacteria, but only S. maltophilia possess atzD. Thus, by cultivating Arthrobacter sp. on these herbicides, cyanuric acid accumulation was observed. When the binary community was cultivated in the biofilm reactor, at all the loading rates probed, both herbicides were entirely removed. However, complete biodegradation of cyanuric acid was not achieved. CONCLUSIONS: Even with a two‐stage reactor, cyanuric acid was only partially removed. This fact could be attributed to the absence, in the second stage, of an easily degradable energy source, required by S. maltophilia for the uptake and cometabolic degradation of the recalcitrant heterocyclic ring. Responding to differences in nutritional conditions prevailing at each reactor stage, local differences in species' predominance were clearly detected by microbiological and molecular biology methods. Copyright © 2010 Society of Chemical Industry 相似文献
27.
This work focuses on poly(lactic acid) (PLA) formulations with improved toughness by physical blending with thermoplastic maize starch (TPS) plasticized with aliphatic–aromatic copolyester up to 30 wt %. A noticeable increase in toughness is observed, due to the finely dispersed spherical TPS domains in the PLA matrix. It is worth to note the remarkable increase in the elongation at break that changes from 7% (neat PLA) up to 21.5% for PLA with 30 wt % TPS. The impact‐absorbed energy is markedly improved from the relatively low values of neat PLA (1.6 J m?2) up to more than three times. Although TPS is less thermally stable than PLA due to its plasticizer content, in general, PLA/TPS blends offer good balanced thermal stability. The morphology reveals high immiscibility in PLA/TPS blends, with TPS‐rich domains with an average size of 1 μm, finely dispersed which, in turn, is responsible for the improved toughness. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45751. 相似文献
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The effect of three additives derived from pine resin, namely, gum rosin (GR) and two pentaerythritol ester of GR, Lurefor (LF) and Unik Tack (UT), in 5, 10, and 15 wt %, on the properties of Mater-Bi, based on plasticized starch, poly(butylene adipate-co-terephthalate), and poly(ε-caprolactone) (PCL), obtained by injection molding processes, was studied. The mechanical, microstructural, and thermal properties were evaluated. LF had a cohesive behavior with the components of Mater-Bi, increasing the toughness of the material up to 250% accompanied by an increase of tensile modulus and tensile strength. UT had an intermediate behavior, conferring cohesive and plasticizing effects, allowing an increase of 105% in impact resistance. GR had a more marked plasticizing effect. This allows processing temperatures of about 50 °C lower than those used for neat Mater-Bi. In addition, an increase of the elongation at break, toughness, and impact resistance in 370, 480, and 250%, respectively, was achieved. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48236. 相似文献
30.
Ainhoa Fernández-Tena Itziar Otaegi Lourdes Irusta Victor Sebastián Gonzalo Guerrica-Echevarria Alejandro Jesus Müller Nora Aranburu 《大分子材料与工程》2023,308(12):2300213
In this work, the effectiveness of seven commercial compatibilizers is tested in polylactide (PLA)/poly(ε-caprolactone) (PCL) blends with different compositions to obtain a high-impact PLA. None of the compatibilizers is effective for 90/10 and 80/20 PLA/PCL compositions, as no improvement of the impact strength is observed. For the 70/30 composition, compatibilizers having glycidyl methacrylate (GMA) and acrylate groups in their structure are proved the most effective, as the morphological change towards co-continuity induced by them leads to significant impact strength improvements (of ≈345% and 90% with respect to the neat PLA and the noncompatibilized PLA/PCL 70/30 blend, respectively). The 70/30 PLA/PCL composition, as it shows the best balance of properties, and the best compatibilizer (ElvaloyPTW) are chosen to carry out the optimization of the compatibilizer content. It is found that adding 6 phr to the blend results in highly toughened and ductile blends while maintaining a high modulus and yield strength values. Larger compatibilizer contents lead to even higher impact strength values, but the low-strain mechanical properties are notably reduced. Thus, in this work, a simple and easily scalable method to produce high-impact PLA is shown, as it implies the compounding of three commercially available components without involving any toxic solvents. 相似文献