Browsing by Issue Date, starting with "2023-04"
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- Green Fractionation Approaches for the Integrated Upgrade of Corn CobsPublication . Fialho, João; Moniz, Patricia; Duarte, Luís C.; Carvalheiro, FlorbelaABSTRACT: Corn cob is an abundant agricultural residue worldwide, with high potential and interesting composition, and its valorization still needs to be studied. Selectively fractionating its structural components (hemicellulose, cellulose, and lignin), value-added products can be produced, eliminating waste. In this work, integrated fractionation approaches were developed and evaluated. First, an organosolv process was optimized (ethanol:water, 50:50, w/w). Then, as a comparative method, alkaline delignification (using NaOH, 1-2%) was also studied. The organosolv process allowed a significant delignification of the material (79% delignification yield) and, at the same time, a liquid phase containing a relevant concentration (14.6 g/L) of xylooligosaccharides (XOS). The resulting solid fraction, rich in cellulose, showed an enzymatic digestibility of 90%. The alkaline process increased the delignification yield to 94%, producing a solid fraction with a cellulose enzymatic digestibility of 83%. The two later techniques were also used in a combined strategy of hydrothermal processing (autohydrolysis) followed by delignification. The first allowed the selective hydrolysis of hemicellulose to produce XOS-rich hydrolysates (26.8 g/L, 67.3 g/100 g initial xylan). The further delignification processes, alkaline or organosolv, led to global delignification yields of 76% and 93%, respectively. The solid residue, enriched in glucan (above 75% for both combined processes), also presented high enzymatic saccharification yields, 89% and 90%, respectively. The fractionation strategies proposed, and the results obtained are very promising, enabling the integrated upgrading of this material into a biorefinery framework.
- 3D electrical structure definition of aquifer systems in the Kalahari basin in Southern Angola based on legacy data reprocessingPublication . Ramalho, Elsa; Francés, Alain Pascal; Santos, Fernando Monteiro; Victorino, Américo da MataABSTRACT: The Kalahari-Ohangwena transboundary aquifer system, recently identified in Northern Namibia, comprises 3 major aquifers with very different characteristics. The shallowest is discontinuous and with limited reserves, but it has local importance in water supply for the population, since it is easy to reach, and often presents good hydrochemical quality. An intermediate deeper aquifer is characterized by high salinity while the deepest aquifer, also mostly saline, can present zones with fresh water. However, the latter is located at considerable depths and is shaped by the bottom of the basin basement. There hasn't been a systematic hydrogeological data acquisition for decades in this area of Angola, but legacy electrical resistivity data reprocessing from geophysical surveys conducted >50 years ago in the Cunene Province allowed the construction of a quasi-3D geoelectrical model for the Angolan side of KOH aquifer system in the Cuvelai-Etosha basin. This model is based on 482 vertical electrical soundings carried out in 1966-67, using the Schlumberger array, that contribute to confirming the presence of the Kalahari-Ohangwena aquifer system in Angola. The obtained quasi-3D model highlights the geoelectrical features of hard bedrock and is validated with other hydrogeological and geophysical information. The quasi-3D electrical resistivity data is interpreted using selected boreholes and two time-domain electro-magnetics transects carried out in Namibia, in the 2000s. Although both geophysical data acquisitions were >40 years apart, the results show a very good correlation between the deeper aquifer and the aquitard separating the intermediate aquifer from the deeper aquifer either with the results from Namibia or the borehole data. This is a direct result of the lack of alteration in the hydraulic conditions over these decades, without significant anthropogenic activity and negligible extraction from deep wells. Based on this analysis, the original dataset was considered a reliable source and this quasi-3D model was validated. Furthermore, the model can be considered in the future as an important tool for groundwater resources management, as well as a good starting point for further hydrogeological research in the province of Cunene.
- Kinetics of the Release Sugars from the Enzymatic and Physico-Chemical Pre-treated Sugarcane Bagasse and Residual Forest BiomassPublication . Codato-Zumpano, Carolina Brito; Gírio, Francisco; Carvalheiro, Florbela; Marques, Susana; Ceccato-Antonini, Sandra Regina; Bastos, ReinaldoABSTRACT: Several pre-treatments are used to release sugars from lignocellulosic materials that are used to produce second-generation ethanol (2G). This study aimed to evaluate the kinetic release of glucose and xylose through the enzymatic and physical treatments of sugarcane bagasse and residual forest biomass, focusing on the ratio between hexose and pentose. Enzymatic hydrolysis after hydrothermal pre-treatment under different conditions, at 170, 170 and 190 degrees C, 170 and 190 degrees C with sulfuric acid, and 170 and 190 degrees C with the Organosolv solvent, all of them for 10 min, were performed with sugarcane bagasse and residual forest biomass, and the kinetic parameters of sugar release were evaluated. The results indicated that compared to hydrothermal and combined hydrothermal and dilute acid hydrolysis, organosolvation process led to higher release of glucose in hydrolysates from both biomasses, with a maximum yield of 14.12 and 33.33 g L-1, respectively. On the other hand, the highest glucose/xylose ratio (about 19), which will facilitate its subsequent use for fermentation, was obtained from sugarcane bagasse after hydrothermal treatment at 170 and 190 degrees C. This ratio was higher for all treatments when compared to untreated biomass, which indicated that temperature and acid affected xylose instead of glucose.
- Development of the operational model and methodology of collecting data, updating, and sharing methodologies to specific groups of stakeholdersPublication . Kochanska, Ewa; Adamkiewicz, Iwona; Wozniak, Katarzyna; Przygodzki, Zbigniew; Trippner-Hrabi, Justyna; Feltynowski, Marcin; Szafranska, Ewa; Jeziorska-Biel, Pamela; Nalej, Marta; Jażdżewska, Iwona; Adamus, Jagoda; Chadzyński, Jacek; Podgórski, Marcin; Bielinski, Dariusz; Siciński, Mariusz; Gozdek, Tomasz; Wręczycki, Jakub; Okraska, Michal; Benedetti, Vittoria; Menin, Lorenzo; Patuzzi, Francesco; Baratieri, Marco; Peppas, Antonis; Politi, Chrysa; Skendera, Doris; Lenssen, Jip; Turati, Daniele; Ravaglia, Pieter; Imiela, Mateusz; Eusebio, Ana; Reis, Alberto; Sousa Rocha, Cristina; Camocho, David; Alexandre, Jorge; Quental, Lídia; Moura, Patrícia; Patinha, Pedro; Lukasik, Rafal M.; Wozniak, Patrycja; Tyczkowski, Adam; Bergamin, Sara; Waszak, Lukasz; Laskowska, Agnieszka; Mirys, Magdalena; Pakowska, Anna; Kałucka, Diana; Straszyńska-Pięta, Katarzyna; Rocha, Monike; Pascale, Carmine; Meletis, Konstantinos; Kehri, Roula; Gazis, Nikos; Stamatakis, Andreas; Bos, Sander; Fonseca, Graca; Cabral, Alexandra; Wojdal, LailaABSTRACT: The overall objective of the FRONTSH1P project is to ensure the green and just transition of the Polish Lodzkie Region towards decarbonization and territorial regeneration through demonstration at TRL7 of four Circular Systemic Solutions (CSS), interconnected one each other and facing the identified regional challenges/opportunities. FRONTSH1P systemic approach will be enabled by a circular governance model that connects environmental policies with social justice through just transition ensuring environmental sustainability, jobs and social inclusion. The flexibility and modularity of the four CSSs guarantee a high replicability and scalability to other territories across Europe and beyond and this will be demonstrated with the involvement of four additional Regions across EU. This report – Deliverable 2.2 (D2.2) is the result of the work carried out under the Work Package 2 - Regional Systemic Circular Economic Approach, Task 2.2. - Regional Circularity Booster Toolkit. D2.2 meets the FRONTSH1P key enabler and requirement, presents the initial approach of the digital platform creation and methodology for data collection and sharing scheme elaboration. The EU General Data Protection Regulation and open data compliant frameworks have been addressed in D2.2 too.
- Metallogenetic potencial of the Paleoproterozoic mafic-ultramafic Hamutenha intrusion (SW Angola). New data from PLANAGEO project [Abstract]Publication . Morais, Igor; Batista, Maria Joao; Represas, Patricia; Albardeiro, Luís; Prazeres, Cátia; Plastov, José Manuel; Sousa, João Carlo; Bravo, Paulo; Sousa, Pedro; Carvalho, João; Rodrigues, José Feliciano; de Oliveira, Daniel Pipa Soares; Cordeiro, DomingosABSTRACT: In the SW sector of the Angolan shield occur the Kunene Anorthositic Complex (KAC), one of the most remarkable magmatic anorthositic suites worldwide. The KAC is considered a long-lived magmatic system that operated in the area intermittently during the Mesoproterozoic (1450 ± 2 Ma to 1371 ± 2.5 Ma). Smaller mafic-ultramafic intrusive bodies ranging in composition from dunite to harzbugite, pyroxenite, troctolite and gabbro are located in the KAC periphery (e.g. Epupa, Ombuku, Hamutenha, Oncócua). The Hamutenha body is a 3 km long oriented NW-SE, banded intrusion with internal zonation hosted in the Paleoproterozoic granitic rocks (1970 ± 2 Ma). The internal zone is composed by rocks with ultramafic nature, mostly harzburgites and dunites with diorites in the external zone.
- Late Cretaceous post-rift magma emplacement offshore the West Iberian Margin [Abstract]Publication . Pereira, Ricardo; Escada, Cláudia; Represas, Patricia; Ramalho, R.S.; Mata, João; Rosas, Filipe M.ABSTRACT: The West Iberian Margin is a prime example of a magma-poor hyperextended continental margin. However, the margin is punctuated by three discrete Mesozoic magmatic events, from which the last, occurring 20-40 M.a. after complete lithospheric breakup of the Iberia-Newfoundland conjugate margin, is related to the late Cretaceous Atlantic Alkaline Province. It is characterised onshore by multiple outcropping intrusive (Sintra, Sines and Monchique) and extrusive (e.g., the Lisbon Volcanic Complex) alkaline suites of magmatism, and offshore by conspicuous and enigmatic magnetic anomalies, suggesting additional magmatic features.
- Bedding mortars from medieval ceramic flooring from the Alcobaça Monastery in PortugalPublication . Carvalho, Fernanda; Nunes, A.; Pagará, A.; Costeira, I.; Silva, Teresa; Leal, Nuno; Simão, J.; Galhano, Carlos; Águas, Hugo; Lima, M.M.R.A.; Veiga, JPABSTRACT: Bedding mortars are fundamental materials to ensure the stability of titles, especially in the case of flooring which withstand the impact of people circulation. In a church, the quality of mortars, tiles pieces and their maintenance over time can be decisive for pavement durability. Inside the church of Santa Maria de Alcobaça Monastery, stone slabs are currently the main and the most applied type of paving in terms of covered area.
- A Distributed Smart Battery Management System: sBMS, for Stationary Energy Storage ApplicationsPublication . Gano, António; Rangel, C. M.ABSTRACT: Currently, electric energy storage systems for stationary applications have known an increasing interest, namely with the integration of local renewable energy power sources into energy communities. Li-ion batteries are considered the leading electric storage devices to achieve this integration, and Battery Management Systems (BMS) are decisive for their control and optimum performance. In this work, the advancement of a smart BMS (sBMS) prototype with a modular distributed topology is described. The system, still under development, has a distributed architecture, with modular characteristics, to operate with different battery pack topologies and charge capacities, integrating adaptive algorithms for functional state real time monitoring and management of multicellular Li-ion batteries, and is intended for application in the context of a local energy community fed by renewable energy sources.
- Cultural Heritage, Materials Science and Synchrotron Radiation: a perspective from a group of Portuguese usersPublication . Veiga, JP; Coutinho, ML; Silva, Teresa; Figueiredo, Elin; Lima, M.M.R.A.; Saraiva, A.S.; Carvalho, FernandaABSTRACT: In this communication, examples to be presented are related to ancient ceramics, glasses, archaeological slags, inorganic pigments and lithologic materials where we were able to gain new insights into composition, structure and degradation processes, contributing to their preservation and interpretation for future generation.