Browsing by Keyword "Chemistry (miscellaneous)"
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Item Bioaccessibility and Antioxidant Capacity of Grape Seed and Grape Skin Phenolic Compounds After Simulated In Vitro Gastrointestinal Digestion(2024) Elejalde, Edurne; Villarán, María Carmen; Esquivel, Argitxu; Alonso, Rosa María; Alimentación SostenibleGrapes present recognized beneficial effects on human health due to their polyphenolic composition. The grape overproduction together with the wine sales down and the world socioeconomic situation makes the wine grape valorization a promising strategy to give an added-value to this natural product. The objective of the present work was to study the influence of in vitro gastrointestinal digestion on antioxidant capacity and polyphenolic profile of skin and seed extracts of different grape varieties (Tempranillo, Graciano, Maturana tinta and Hondarrabi zuri). After in vitro gastrointestinal digestion, total phenolic content (TPC) of seed polyphenolic extracts decreased significantly for all the varieties. The highest decrease was for Tempranillo going from 108 ± 9 to 50 ± 3 mg / g dry matter (dm). This variety also showed the highest decrease of 90% in antioxidant capacity. However, for all the skin polyphenolic extracts there was an increase in TPC. The highest variation was also for Tempranillo. It varied from 10.1 ± 0.8 to 55.1 ± 0.9 mg / g dm. Among red varieties Tempranillo skin polyphenolic extract showed the lowest undigested anthocyanin content but the highest bioaccessibility index (BI) of 77%. For flavanols, flavonols and procyanidins the seed polyphenolic extracts showed a BI at the intestinal phase between 11% for (+)-epicatechin gallate to 130% procyanidin A2. The results of this study suggest that grape skin extracts and grape seed extracts are a reliable source of bioaccessible antioxidant polyphenols, to be used for the development of antioxidant supplements with specific functionalities depending on the grape variety.Item Central lessons from the historical analysis of 24 reinforced-concrete structures in northern Spain(2016-07-01) Marcos, Ignacio; San-José, José Tomás; Garmendia, Leire; Santamaría, Amaia; Manso, Juan Manuel; Tecnalia Research & InnovationSince the late-nineteenth century, the use of reinforced-concrete as a structural material has proliferated and is now commonplace in the modern built environment. Some of the structures from that century are even considered cultural heritage. In the early stages of its technical development, concrete was seen as practically immutable over time; however, prolonged exposure to environmental agents has revealed its very significant problems of weakening strength and durability. A total of 24 aging reinforced-concrete structures in the Basque Country (northern Spain) and their behavior over time are analyzed in this paper. Reference is made to pathological reports, categorized for the purposes of this study, which characterize their concrete and steel components. This contribution greatly enhances our knowledge of each structure for future studies and for the improvement of their conservation strategies.Item The chemical and physical properties of lignin bio-oils, facts and needs(2023-04) Gracia-Vitoria, J.; Gándara, S. Corderí; Feghali, E.; Ortiz, P.; Eevers, W.; Triantafyllidis, K. S.; Vanbroekhoven, K.; BIOECONOMÍA Y CO2Lately, the interest in lignin valorization has notably grown within the scientific community. In the last decade, the number of publications focusing on lignin as an alternative to fossil-based resources has exponentially increased. Different strategies have been employed to valorize lignin as a source of renewable fuel and building blocks for chemicals and materials development. Of these strategies, lignin depolymerization producing lignin oils (bio-oils) has been recently explored on laboratory and pilot scale. The produced bio-oil exhibits unique chemical and physical properties that depend on the type of lignin with regard to the nature of parent biomass and can be further tailored by both the isolation and the depolymerization process conditions. This review aims to group the work done on the production and valorization of bio-oils to provide a common description of the depolymerized lignin oils. This work proposes reporting guidelines of bio-oil properties required to bridge the gap between the depolymerization techniques and chemicals/materials development using the bio-oils properties.Item Definition of the procedure to determine the suitability and durability of an anti-graffiti product for application on cultural heritage porous materials(2012-01) García, Oihana; Malaga, Katarina; Tecnalia Research & InnovationAnti-graffiti protection is becoming a common practice in many urban buildings, especially in areas of social decay. When Cultural Heritage objects are affected by graffiti, the application of anti-graffiti products can result not only in an unsatisfactory result but also in an irreversible damage of an invaluable cost. The materials commonly found in these constructions are very frequently porous and present different types of decay forms. For this reason, the protection of these materials should be carefully considered. This paper proposes a criterion to decide on the suitability and durability of an anti-graffiti product prior to its application in a porous surface of a protected building. Performance classifications are defined for a series of properties including colour and gloss, and hydric and durability properties, and minimum acceptable values or reductions in these properties are recommended.Item Effect of the Metal Transfer Mode on the Symmetry of Bead Geometry in WAAM Aluminum(2021-07-10) Veiga, Fernando; Suárez, Alfredo; Aldalur, Eider; Bhujangrao, Trunal; Tecnalia Research & Innovation; FABRIC_INTELThe symmetrical nature in the case of wall fabrication by wire arc additive manufacturing (WAAM) has been observed in the literature, but it has not been studied as a source of knowledge. This paper focuses on the comparative study of three drop transfer methods employing Gas Metal Arc Welding (GMAW) technology, one of the most reported for the manufacture of aluminum alloys. The transfer modes studied are the well-known pulsed GMAW, cold arc, and the newer pulsed AC. The novelty of the last transfer mode is the reversal of the polarity during the preparation phase of the substance for droplet deposition. This study compares the symmetry of zero beads to determine the best parameters and transfer modes for wire arc additive manufacturing of 5 series aluminum. The pulsed transfer modes show values of 0.6 for symmetry ratio, which makes them more interesting strategies than cold arc with a symmetry ratio of 0.5. Furthermore, the methodology proposed in this study can be extrapolated to other materials manufactured with this technology.Item Evaluating and managing the sustainability of investments in green and sustainable chemistry: An overview of sustainable finance approaches and tools(2022-08) Yilan, Gülşah; Cordella, Mauro; Morone, Piergiuseppe; Tecnalia Research & InnovationGreen chemistry (GC) was developed to maximise resource efficiency and minimise hazards in chemical processes and products. Over time, the approach evolved into green and sustainable chemistry (GSC), which aims at promoting the development of an ecologically friendly society. GSC encourages society's reliance on sustainable materials and technologies/processes and supports the ambitious sustainability targets set by international organisations. It also steers public attention to the provision of sustainable solutions for producers, consumers and investors. Since GSC implementation requires significant financial investment, this paper describes a broad range of approaches and tools to assess the sustainability of potential investments and shows, although with a primary focus on environmental sustainability, how life cycle approaches could be used to define enhanced key performance indicators. Thus, the paper may serve as a useful reference for: (i) chemical companies interested in evaluating the sustainability performance of activities requiring financial investment, and (ii) investors interested in evaluating the sustainability of potential financial investments.Item Fluidized Bed Membrane Reactors for Ultra Pure H2 Production - A Step forward towards Commercialization(2016-03-19) Helmi, Arash; Fernandez, Ekain; Melendez, Jon; Pacheco Tanaka, David A.; Gallucci, Fausto; van Sint Annaland, Martin; TECNOLOGÍAS DE HIDRÓGENO; Tecnalia Research & Innovation; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSIn this research the performance of a fluidized bed membrane reactor for high temperature water gas shift and its long term stability was investigated to provide a proof-of-concept of the new system at lab scale. A demonstration unit with a capacity of 1 Nm3/h of ultra-pure H2 was designed, built and operated over 900 h of continuous work. Firstly, the performance of the membranes were investigated at different inlet gas compositions and at different temperatures and H2 partial pressure differences. The membranes showed very high H2 fluxes (3.89E 6 mol m 2 Pa 1 s 1 at 400 C and 1 atm pressure difference) with a H2/N2 ideal perm-selectivity (up to 21,000 when integrating five membranes in the module) beyond the DOE 2015 targets. Monitoring the performance of the membranes and the reactor confirmed a very stable performance of the unit for continuous high temperature water gas shift under bubbling fluidization conditions. Several experiments were carried out at different temperatures, pressures and various inlet compositions to determine the optimum operating window for the reactor. The obtained results showed high hydrogen recovery factors, and very low CO concentrations at the permeate side (in average <10 ppm), so that the produced hydrogen can be directly fed to a low temperature PEM fuel cell.Item Methodology for the Path Definition in Multi-Layer Gas Metal Arc Welding (GMAW)(2023-02) Curiel, David; Veiga, Fernando; Suarez, Alfredo; Villanueva, Pedro; FABRIC_INTELThe reconstruction of the geometry of weld-deposited materials plays an important role in the control of the torch path in GMAW. This technique, which is classified as a direct energy deposition technology, is experiencing a new emergence due to its use in welding and additive manufacturing. Usually, the torch path is determined by computerised fabrication tools, but these software tools do not consider the geometrical changes along the case during the process. The aim of this work is to adaptively define the trajectories between layers by analysing the geometry and symmetry of previously deposited layers. The novelty of this work is the integration of a profiling laser coupled to the production system, which scans the deposited layers. Once the layer is scanned, the geometry of the deposited bead can be reconstructed and the symmetry in the geometry and a continuous trajectory can be determined. A wall was fabricated under demanding deposition conditions, and a surface quality of around 100 microns and mechanical properties in line with those previously reported in the literature are observed.Item Morphology and N2 Permeance of Sputtered Pd-Ag Ultra-Thin Film Membranes(2016-02-10) Fernandez, Ekain; Sanchez-Garcia, Jose Angel; Viviente, J.L.; van Sint Annaland, Martin; Gallucci, Fausto; Pacheco Tanaka, David A.; Tecnalia Research & Innovation; TECNOLOGÍAS DE HIDRÓGENO; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSThe influence of the temperature during the growth of Pd-Ag films by PVD magnetron sputtering onto polished silicon wafers was studied in order to avoid the effect of the support roughness on the layer growth. The surfaces of the Pd-Ag membrane films were analyzed by atomic force microscopy (AFM), and the results indicate an increase of the grain size from 120 to 250–270 nm and film surface roughness from 4–5 to 10–12 nm when increasing the temperature from around 360–510 K. After selecting the conditions for obtaining the smallest grain size onto silicon wafer, thin Pd-Ag (0.5–2-µm thick) films were deposited onto different types of porous supports to study the influence of the porous support, layer thickness and target power on the selective layer microstructure and membrane properties. The Pd-Ag layers deposited onto ZrO2 3-nm top layer supports (smallest pore size among all tested) present high N2 permeance in the order of 10−6 mol•m−2•s−1•Pa−1 at room temperature.Item Multi-criteria decision-making for grading the rehabilitation of heritage sites. Application in the historic center of La Habana(2017-07) Piñero, Ignacio; San-José, José T.; Rodríguez, Patricia; Losáñez, Milagros M.; E&I SEGURAS Y RESILIENTESThe rehabilitation of an historic city centre is approached in this investigation through a multi-criteria decision-making methodology. The methodology assists a panel of experts to take key decisions on rehabilitation options. The viability of the methodology is verified through its practical application in the Historic Centre of La Habana, in which extreme situations are analyzed: a culturally protected (World Heritage) urban zone with many degraded buildings at risk of collapse. In view of the urgency of the rehabilitation decisions, efficient criteria for “emergency actions” on the 3593 buildings of that historic centre were analyzed. The conclusions were that 1033 buildings were in need of one or various emergency actions, with 169 awaiting demolition or restoration and, finally, 597 in need of non-urgent repairs.Item Ochratoxin a removal from red wine by several oenological fining agents: Bentonite, egg albumin, allergen-free adsorbents, chitin and chitosan(2012-07) Quintela, S.; Villaran, M. C.; De Armentia, López I.; Elejalde, E.; Alimentación SostenibleThe ability of several oenological fining agents to remove ochratoxin A (OTA) from red wine was studied. The adsorbents tested were activated sodium bentonite, egg albumin, allergen-free adsorbents (complex PVPP, plant protein and amorphous silica (complex) and high molecular weight gelatine), and the non-toxic biodegradable polymers (chitin and chitosan). Several dosages within the oenological use range were tested and the wine pH, colour parameters and polyphenol concentration impact associated with each fining agent were studied. Generally, OTA removal achieved in all treatments was higher when the adsorbent dosage increased, but the impact on wine quality also was higher. Chitin at 50ghl_1 removed 18% the OTA without affecting significantly the wine-quality parameters. At the highest dosage tested the gelatine and complex treatments achieved greater OTA removal (up to 39-40%) compared with bentonite, egg albumin and chitin. Moreover, the gelatine and the complex had a lower impact on colour parameters and polyphenol concentration compared with chitosan, whilst OTA was reduced to around 40%. Chitosan achieved the greatest OTA removal (67%), but it strongly affected the wine-quality parameters. Otherwise, bentonite showed a relative efficiency to remove OTA, but the CI value decreased considerably. The egg albumin treatment only removed OTA up to 16% and moreover affected strongly the CI value and CIELab parameters. The results of this survey showed that the non-toxic chitin adsorbent and the allergen-free adsorbents tested could be considered as alternative fining agents to reduce OTA in red wine.Item Pore flow-through catalytic membrane reactor for steam methane reforming: characterization and performance(2022-07-12) Angulo, M.; Agirre, I.; Arratibel, A.; Llosa Tanco, M. A.; Pacheco Tanaka, D. A.; Barrio, V. L.; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSA series of pore flow-through catalytic nonselective membrane reactors (PTCMRs) were studied for steam methane reforming (SMR) in the 500 to 900 °C temperature range under 10 barg pressure and a steam-to-carbon ratio of 5. The reactants flow through the pores of the membrane where they react on contact with the Pd nanoparticles. Various reactor configurations were prepared and tested with porous α-Al2O3-based ceramic tubes with one or more γ-Al2O3/YSZ layers on the external surface. The palladium content and dispersion affect the catalytic activity of the reactors and the results show that the efficiency of the reactions depends on the number of γ-Al2O3/YSZ layers.Item Recent Advances in Pd-Based Membranes for Membrane Reactors(2017-01-01) Arratibel Plazaola, Alba; Pacheco Tanaka, David A.; Van Sint Annaland, Martin; Gallucci, Fausto; Tecnalia Research & Innovation; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSPalladium-based membranes for hydrogen separation have been studied by several research groups during the last 40 years. Much effort has been dedicated to improving the hydrogen flux of these membranes employing different alloys, supports, deposition/production techniques, etc. High flux and cheap membranes, yet stable at different operating conditions are required for their exploitation at industrial scale. The integration of membranes in multifunctional reactors (membrane reactors) poses additional demands on the membranes as interactions at different levels between the catalyst and the membrane surface can occur. Particularly, when employing the membranes in fluidized bed reactors, the selective layer should be resistant to or protected against erosion. In this review we will also describe a novel kind of membranes, the pore-filled type membranes prepared by Pacheco Tanaka and coworkers that represent a possible solution to integrate thin selective membranes into membrane reactors while protecting the selective layer. This work is focused on recent advances on metallic supports, materials used as an intermetallic diffusion layer when metallic supports are used and the most recent advances on Pd-based composite membranes. Particular attention is paid to improvements on sulfur resistance of Pd based membranes, resistance to hydrogen embrittlement and stability at high temperature.Item A resources ecosystem for digital and heritage-led holistic knowledge in rural regeneration(2022-09-01) Tamborrino, Rosa; Patti, Edoardo; Aliberti, Alessandro; Dinler, Mesut; Orlando, Matteo; de Luca, Claudia; Tondelli, Simona; Barrientos, Francisco; Martin, John; Cunha, Luís F.M.; Stam, Andries; Nales, Aad; Egusquiza, Aitziber; Amirzada, Zahra; Pavlova, Irina; LABORATORIO DE TRANSFORMACIÓN URBANAThis paper presents a digital resources ecosystem prototype of integrated tools and resources to support heritage-led regeneration of rural regions, thanks to a deeper understanding of the complexity of cultural natural landscapes throughout their historical and current development. The ecosystem is conceived as a distributed software platform establishing data ecosystem and open standards for the management of information, aimed at providing different services and applications to address the needs of the various end-users identified. The platform has been conceived and realised in the framework of a Horizon 2020 research project, with a view to building a set of holistic knowledge about rural regions and their cultural and natural heritage and making it available for long-lasting heritage-led territorial processes of change. It is the product of a multidisciplinary collaboration amongst heritage, digital humanities and ICTs experts, and combines data and methodologies from a range of approaches to humanities together with the customisation of effective digital tools. It has been designed for deployment also in cloud systems compliant with the Infrastructure-as-a-Service paradigm. All data is Findable, Accessible, Interoperable, Reusable (FAIR data). It hosts and integrates different tools, making the data gathered with/for local stakeholders usable and making the same data re-usable within the tools’ functions, generating integrated heritage knowledge. It comprises data on 19 rural pilot territories, where the tools and their integration have been developed and tested, while 62 more are partially included as additional territories which participate in certain activities within the project. The main testers for this platform and its functions are the local stakeholders of these territories. The paper describes and analyses the platform and its impact, discussing the integration of tools as an innovative approach that goes beyond the use of individual tools in shaping a multidimensional vision. It also offers an analysis of the potential of an integrated digital ecosystem in evidence-based and place-based regeneration strategies. Some reflections for developments and cooperation during the pandemic are also presented.Item Supercritical hydrothermal flow synthesis of xonotlite nanofibers(2018-06-01) Díez-García, Marta; Gaitero, J.J.; Santos, J.I.; Dolado, Jorge S.; Aymonier, Cyril; Tecnalia Research & Innovation; ECOEFICIENCIA DE PRODUCTOS DE CONSTRUCCIÓNThis article reports a satisfactory and innovative method for the synthesis of xonotlite using a flow reactor and supercritical water. This study widens the variety of inorganic nanofibers produced in record breaking times by means of continuous reactors working under supercritical water conditions. In particular, the synthesis time of xonotlite, which takes normally more than 5 h, was reduced to only 20s by carrying out the reaction at 400 °C and 23.5 MPa. Resulting product was studied by several characterization techniques: x-ray diffraction, transmission electron microscopy, 29Si and 1H nuclear magnetic resonance and infrared spectroscopy. Furthermore, obtained product consisted of highly pure and crystalline flat nanofibers of 1–10 μm long with a length to diameter ratio of the order of 100. Also, the typical deviation from the ideal structure observed by nuclear magnetic resonance and the presence of Si-OH were explained in terms of surface defects. This work reinforces the interests of using supercritical conditions for the fast synthesis of crystalline nano-calcium silicates which, due to the number of potential industrial applications and the scalability of the technology, might represent technological breakthrough.Item Three-Dimensional Finite Element Modelling of Sheet Metal Forming for the Manufacture of Pipe Components: Symmetry Considerations: Symmetry Considerations(2022-01-25) Bhujangrao, Trunal; Veiga, Fernando; Penalva, Mariluz; Costas, Adriana; Ruiz, Cristina; Tecnalia Research & Innovation; FABRIC_INTELThe manufacture of parts by metal forming is a widespread technique in sectors such as oil and gas and automotives. It is therefore important to make a research effort to know the correct set of parameters that allow the manufacture of correct parts. This paper presents a process analysis by means of the finite element model. The use case presented in this paper is that of a 3-m diameter pipe component with a thickness of 22 mm. In this type of application, poor selection of process conditions can result in parts that are out of tolerance, both in dimensions and shape. A 3D finite element model is made, and the symmetry of the tube section generated in 2D is analysed. As a novelty, an analysis of the process correction as a function of the symmetrical deformation of the material in this case in the form of a pipe is carried out. The results show a correct fitting of the model and give guidelines for manufacturing.