Investigación

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Mostrando 1 - 20 de 37

Adsorption of polycyclic aromatic hydrocarbons by natural, synthetic and modified clays
(MDPI, 2021-11) Satouh, Sara; Martín Bueno, Julia; Orta Cuevas, María del Mar; Medina Carrasco, Santiago; Messikh, Nabil; Bougdah, Nabil; Santos Morcillo, Juan Luis; Aparicio Gómez, Irene; Alonso Álvarez, Esteban; Universidad de Sevilla. Departamento de Química Analítica; Alonso Álvarez, Esteban; Universidad de Sevilla. FQM344: Análisis Químico Industrial y Medioambiental
Polycyclic aromatic hydrocarbons (PAHs) are of major scientific concern owing to their widespread presence in environmental compartments and their potential toxicological effects on humans and biota. In this study, the adsorption capacity of natural (montmorillonite (Mt)), synthetic (Na-Mica-4), and modified (with octadecylamine and octadecyltrimethylamine (ODA-Mt, ODA-Mica-4, and ODTMA-Mt and ODTMA-Mica-4)) clays were assessed and compared for the removal of 16 PAHs. Materials were synthesized and characterized by X-Ray diffraction, Zeta potential, and Fourier-transform infrared spectroscopy. The results showed its correct preparation and the incorporation of PAHs in the structure of the clays after the adsorption tests. The proposed materials were effective PAH adsorbents, with adsorption percentages close to 100%, in particular those using Mt. Mt and Na-Mica-4 presented a better adsorption capacity than their organofunctionalized derivatives, indicating that the adsorption of PAHs may occur both in the surface part and in the interlayer. The proposed adsorbents take the advantage of being a low cost and highly effective. They can be an interesting alternative for wastewater treatment and soil remediation to prevent PAH contamination.
Analysis of the evolution of the sharing economy towards sustainability. Trends and transformations of the concept
(Elsevier, 2021-04) Heras García de Vinuesa, Ana de las; Relinque-Medina, Fernando; Zamora-Polo, Francisco; Luque Sendra, Amalia; Universidad de Sevilla. Departamento de Ingeniería del Diseño; Junta de Andalucía (Spain) in its programme of projects to promote cross-border cooperation in the Euroregion Alentejo-Algarve-Andalucía; Telefonica Chair “Intelligence in Networks” of the University of Seville (Spain); Universidad de Sevilla. TEP022: Diseño Industrial e Ingeniería del Proyecto y la Innovación
The Sharing Economy has been emerged in recent years as a trend with high growth potential by showing itself to be an innovative model for creating products, services and relationships based on sustainable consumption. The Sharing Economy has emerged as a multidimensional and multidisciplinary concept, which initially only covered areas of the economy and social sciences and which later experienced growth in business, urban planning, tourism, information technology and digital science (industry 4.0) or engineering. This has transformed its development from an economic opportunity to a form of decentralised, equitable and sustainable economy with the creation of new initiatives and companies that have reduced environmental impact by decreasing the use of natural resources. The present study aims to evaluate the evolution of the discourse and the way research has progressed in this incipient sphere of collaborative consumption up to the present day by means of an in-depth analysis of scientific production through bibliometrics and network analysis techniques with the VOSviewer© software and the complete database of publications obtained from the Web Of Science (2152 publications). It also includes the detailed examination of the most relevant bibliographic reviews on Sharing Economics, as well as the main publications on bibliometric analysis. The article evaluates key words, sources, authors, citations, organizations, categories, and countries using various bibliometric techniques. Finally, in the results 5 clusters of thematic categories are obtained where a change in the trend of publications towards the field of clean and green technology is reflected, forming in recent years an agglutinating nucleus of all the disciplines in which “sustainability” acts as the backbone of scientific production. This is a positive development in cleaner production, where institutions and authors from the USA and Europe have risen to the top of the ranking of publications and impact. At a global level, the current commitment to research for the development of accessible, equitable and sustainable products and services is reflected.
Assessing Formability and Failure of UHMWPE Sheets throughSPIF: A Case Study in Medical Applications
(MDPI, 2023-08) Rosa-Sainz, Ana; Silva, M. Beatriz; Beltrán, Ana M.; Centeno Báez, Gabriel; Vallellano Martín, Carpóforo; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte; Universidad de Sevilla. Departamento de Ingeniería Mecánica y de Fabricación; Regional Government of Andalusia- US/JUNTA/FEDER_UE of the PAIDI 2020 P18-RT-3866; Spanish Government Grant reference TED2021-131153B-C22; Universidad de Sevilla. TEP123: Metalurgia e Ingeniería de los Materiales; Universidad de Sevilla. TEP111: Ingeniería Mecánica
This work presents a comprehensive investigation of an experimental study conducted on ultra-high molecular weight polyethylene (UHMWPE) sheets using single point incremental forming (SPIF). The analysis is performed within a previously established research framework to evaluate formability and failure characteristics, including necking and fracture, in both conventional Nakajima tests and incremental sheet forming specimens. The experimental design of the SPIF tests incorporates process parameters such as spindle speed and step down to assess their impact on the formability of the material and the corresponding failure modes. The results indicate that a higher step down value has a positive effect on formability in the SPIF context. The study has identified the tool trajectory in SPIF as the primary influencing factor in the twisting failure mode. Implementing a bidirectional tool trajectory effectively reduced instances of twisting. Additionally, this work explores a medical case study that examines the manufacturing of a polyethylene liner device for a total hip replacement. This investigation critically analyses the manufacturing of plastic liner using SPIF, focusing on its formability and the elastic recovery exhibited by the material.
Assessment of exposure to perfluoroalkyl substances (PFASs) in dogs by fur analysis
(Elsevier, 2021-10) Makowska, Krystyna; Martín Bueno, Julia; Rychlik, Andrzej; Aparicio Gómez, Irene; Santos Morcillo, Juan Luis; Alonso Álvarez, Esteban; Gonkowski, SŁawomir; Universidad de Sevilla. Departamento de Química Analítica; Universidad de Sevilla. FQM344: Análisis Químico Industrial y Medioambiental
Poly- and perfluoroalkyl substances (PFASs) are a large group of chemicals commonly used in various branches of industry, which may adversely affect the living organisms. The aim of this study were to evaluate exposure of dogs to six selected PFASs: five perfluoroalkyl carboxylic acids (perfluorobutanoic acid - PFBuA, perfluoropentanoic acid - PFPeA, perfluorohexanoic acid - PFHxA, perfluoroheptanoic acid - PFHpA, perfluorooctanoic acid – PFOA) and perfluorooctane sulfonic acid (PFOS) through the analysis of fur samples. To our knowledge this is the first study concerning the use of fur samples to evaluation of exposure of domestic animals to PFASs. Relationship between PFASs concentration and age, gender and body weight of animals was also evaluated. Fur samples were collected from 30 dogs living in Olsztyn (Poland). All PFASs studied were detected in the canine fur samples. The highest concentrations were observed in the case of PFOA and PFBuA, detected at concentrations in the range between 1.51 and 66.7 ng/g and 0.98–26.6 ng/g, respectively. During the present study generally no statistically significant differences dependent on gender, age and body weight of animals were found. This study confirms the suitability of fur samples for biomonitoring of exposure to PFASs in domestic animals, what may be important in veterinary toxicology.
Biomonitoring of 21 endocrine disrupting chemicals in human hair samples using ultra-high performance liquid chromatography-tandem mass spectrometry
(Elsevier, 2017-02) Rodríguez-Gómez, Rocío; Martín Bueno, Julia; Zafra-Gómez, Alberto; Alonso Álvarez, Esteban; Vílchez, José Luis; Navalón, Alberto; Universidad de Sevilla. Departamento de Química Analítica; Junta de Andalucía; Ministerio de Economía y Competitividad (MINECO). España; Universidad de Sevilla. FQM344: Análisis Químico Industrial y Medioambiental
Rapid industrial growth has increased human exposure to a large variety of chemicals with adverse health effects. These industrial chemicals are usually present in the environment, foods, beverages, clothes and personal care products. Among these compounds, endocrine disrupting chemicals (EDCs) have raised concern over the last years. In the present work, the determination of 21 EDCs in human hair samples is proposed. An analytical method based on the digestion of the samples with a mixture of acetic acid/methanol (20:80, v/v) followed by a solid-liquid microextraction and analysis by ultra-high performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) was developed and validated. The most influential parameters affecting the extraction method were optimized. The method was validated using matrix-matched calibration and recovery assays. Limits of detection ranged from 0.2 to 4 ng g⁻¹, limits of quantification from 0.5 to 12 ng g⁻¹, and inter- and intra-day variability was under 15% in all cases. Recovery rates for spiked samples ranged from 92.1 to 113.8%. The method was applied for the determination of the selected compounds in human hair. Samples were collected weekly from six randomly selected volunteers (three men and three women) over a three-month period. All the analyzed samples tested positive for at least one of the analyzed compounds.
Breaking Trivium Stream Cipher Implemented in ASIC Using Experimental Attacks and DFA
(MDPI, 2020-12) Potestad Ordóñez, Francisco Eugenio; Valencia Barrero, Manuel; Baena Oliva, María del Carmen; Parra Fernández, María del Pilar; Jiménez Fernández, Carlos Jesús; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. TIC180: Diseño de Circuitos Integrados Digitales y Mixtos
One of the best methods to improve the security of cryptographic systems used to exchange sensitive information is to attack them to find their vulnerabilities and to strengthen them in subsequent designs. Trivium stream cipher is one of the lightweight ciphers designed for security applications in the Internet of things (IoT). In this paper, we present a complete setup to attack ASIC implementations of Trivium which allows recovering the secret keys using the active non-invasive technique attack of clock manipulation, combined with Differential Fault Analysis (DFA) cryptanalysis. The attack system is able to inject effective transient faults into the Trivium in a clock cycle and sample the faulty output. Then, the internal state of the Trivium is recovered using the DFA cryptanalysis through the comparison between the correct and the faulty outputs. Finally, a backward version of Trivium was also designed to go back and get the secret keys from the initial internal states. The key recovery has been verified with numerous simulations data attacks and used with the experimental data obtained from the Application Specific Integrated Circuit (ASIC) Trivium. The secret key of the Trivium were recovered experimentally in 100% of the attempts, considering a real scenario and minimum assumptions.
Comparative analysis of the germination of barley seeds subjected to drying, hydrogen peroxide, or oxidative air plasma treatments
(Wiley-Blackwell, 2022) Perea Brenes, Álvaro; Gómez Ramírez, Ana María; López Santos, Carmen; Oliva Ramirez, Manuel; Molina, Ricardo; Cotrino Bautista, José; García, José L.; Cantos, Manuel; González-Elipe, Agustín R.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Universidad de Sevilla. Departamento de Física Aplicada I; Junta de Andalucía; Ministerio de Ciencia, Innovación y Universidades (MICINN). España; European Cooperation in Science and Technology (COST)
Acceleration in germination time by 12–24 h for barley seeds treated with atmospheric air plasmas may have a significant economic impact on malting processes. In this study, the increase in germination rate and decrease in contamination level upon plasma treatment could not be directly correlated with any significant increase in the water uptake capacity, except for seeds exposed to mild drying treatment. A variety of germination essays have been carried out with seeds impregnated with an abscisic acid solution, a retarding factor of germination, treated with a peroxide solution, and/or subjected to the plasma and drying treatments. Results suggest that plasma and hydrogen peroxide treatments induce the formation of reactive oxygen and nitrogen species that affects the abscisic acid factor and accelerate the germination rate.
Determining the Importance of Physicochemical Properties in the Perceived Quality of Wines
(Institute of Electrical and Electronics Engineers, 2023-10) Luque Sendra, Amalia; Mazzoleni, Mirko; Zamora-Polo, Francisco; Ferramosca, Antonio; Lama-Ruiz, Juan Ramón; Previdi, Fabio; Universidad de Sevilla. Departamento de Ingeniería del Diseño; VII Own Research and Transfer Plan 2023 of the University of Seville under Project 2023/00000378; Universidad de Sevilla. TEP022: Diseño Industrial e Ingeniería del Proyecto y la Innovación
Wine is a relevant part of the diet in many countries, showing significant nutritional properties, providing health benefits to consumers, and having a significant weight in economy. Also, wine plays an important role in many cultures as a part of their social relationships, feasts, or religion where some of them may become a sign of luxury and distinction. For those reasons, objective and subjective quality of wines is an important issue in their production and marketing. To improve wine excellence, some production methods try to relate its physicochemical properties to the quality as it is perceived by humans. Then, modern data prescriptive analysis can be applied to measure the importance (the influence) of each wine attribute. This paper examines and compare several metrics of the attribute importance and its application to the quality-aware design and production of wines. Moreover, for the cases where the perceived quality is characterized using a discrete value, a novel importance metric, based on the Jensen-Shannon Divergence (JSD) is introduced and compared to the existing ones. The results show that JSD clearly overperforms other metrics previously proposed in the literature. Also, it can be asserted that JSD properly reflects the importance of discrete multivalued functions. The results, using this metric in an importance performance analysis of a public wine dataset, show that the main physicochemical attributes of a red wine are citric acidity, alcohol, sulphates and fixed acidity. As for the white wine case, the main attributes are alcohol, free sulfure dioxide and pH.
Development of porous silver nanoparticle/polycaprolactone/polyvinyl alcohol coatings for prophylaxis in titanium interconnected samples for dental implants
(Elsevier, 2022-05) Alcudia Cruz, Ana; Begines Ruiz, Belén; Rodríguez-Lejarraga, Paula; Greyer, Valeria; Fortio Godinho, Vanda Cristina; Pajuelo Domínguez, Eloísa; Torres Hernández, Yadir; Universidad de Sevilla. Departamento de Química Orgánica y Farmacéutica; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte; Universidad de Sevilla. Departamento de Microbiología y Parasitología; Universidad de Sevilla. FQM135: Carbohidratos y Polímeros; Universidad de Sevilla. TEP123: Metalurgia e Ingeniería de los Materiales; Universidad de Sevilla. BIO181: Fitomicrobiomas Como Herramientas Biotecnológicas
Stress shielding phenomenon, poor osseointegration, or bacterial infections of titanium dental implants are widely recognized as key problems that deeply affect their survival rate. In this work, a joint solution to solve these three limitations is proposed. The first two issues were minimized applying porous Ti samples. This substrate exhibits an appropriated biomechanical equilibrium (stiffness and mechanical resistance) and good biofunctionality (ability to promote bone ingrowth). On the other hand, the porous Ti disc was coated with biocompatible and non-toxic polymeric composites matrices using poly-ε-caprolactone and partially acetylated polyvinyl alcohol, combined with silver nanoparticles as a therapeutic antimicrobial agent. The optimization of the best blend composition and optimal nanoparticles concentration were investigated. Finally, the two composites with the best antimicrobial activity were infiltrated into porous Ti discs. The deposited coatings presented good adhesion and a honeycomb-like surface structure that could promote vascularization of the implant and enhance osseointegration.
Effect of Solution Properties in the Development of Cellulose Derivative Nanostructures Processed via Electrospinning
(MDPI, 2022) Sánchez Cid, Pablo; Rubio Valle, José Fernando; Jiménez-Rosado, Mercedes; Pérez-Puyana, Víctor Manuel; Romero García, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química
In the last few years, electrospinning has proved to be one of the best methods for obtaining membranes of a micro and nanometric fiber size. This method mainly consists in the spinning of a polymeric or biopolymeric solution in solvents, promoted by the difference in the electric field between the needle and collector, which is finally deposited as a conjunction of randomly oriented fibers. The present work focuses on using cellulose derivatives (namely cellulose acetate and ethylcellulose), based on the revaluation of these byproducts and waste products of biorefinery, to produce nanostructured nanofiber through electrospinning with the objective of establishing a relation between the initial solutions and the nanostructures obtained. In this sense, a complete characterization of the biopolymeric solutions (physicochemical and rheological properties) and the resulting nanostructures (microstructural and thermal properties) was carried out. Therefore, solutions with different concentrations (5, 10, 15, and 20 wt%) of the two cellulose derivatives and different solvents with several proportions between them were used to establish their influence on the properties of the resulting nanostructures. The results show that the solutions with 10 wt% in acetic acid/H2O and 15 wt% in acetone/N,N-dimethylformamide of cellulose acetate and 5 wt% of ethylcellulose in acetone/N,N-dimethylformamide, exhibited the best properties, both in the solution and nanostructure state.
Enantioselective LC-MS/MS determination of antidepressants, β-blockers and metabolites in agricultural soil, compost and digested sewage sludge
(Elsevier, 2023) Arenas Molina, Marina; Santos Morcillo, Juan Luis; Martín Bueno, Julia; Aparicio Gómez, Irene; Alonso Álvarez, Esteban; Universidad de Sevilla. Departamento de Química Analítica; Junta de Andalucía; Ministerio de Universidades. España
In this work, an analytical method was optimised and validated for the simultaneous extraction and enantioselective determination of chiral β-blockers, antidepressants and two of their metabolites in agricultural soils, compost and digested sludge. Sample treatment was based on ultrasound-assisted extraction and extract clean-up by dispersive solid-phase extraction. Analytical determination was carried out by liquid chromatography-tandem mass spectrometry using a chiral column. Enantiomeric resolutions were in the range from 0.71 to 1.36. Accuracy was in the range from 85 to 127% and precision, expressed as relative standard deviation, was lower than 17% for all the compounds. Method quantification limits were below 1.21–52.9 ng g−1 dry weight (dw) in soil, 0.76–35.8 ng g−1 dw in compost and 13.6–90.3 ng g−1 dw in digested sludge. Application to real samples revealed enantiomeric enrichment in the range especially in compost and digested sludge (enantiomeric fractions up to 1).
Exalted dual-scale surface roughening in laser ablated aluminum capped with a transparent thin film: Wetting and anti-icing behavior
(Elsevier, 2023-09) Ghemras, Ismail; Montes Montañez, Laura; López Santos, Carmen; González-Elipe, Agustín R.; Rico, Víctor; Universidad de Sevilla. Departamento de Física Aplicada I; EU H2020 program under grant agreement 899352 (FETOPEN-01-2018-2019-2020 - SOUNDofICE); AEI-MICINN (España) and FEDER PID2019-110430GB-C21; AEI-MICINN (España) and FEDER PID2020-112620GBI00; EI-MICINN (España) and FEDER PID2019-109603RA-I00; Consejería de Economía, Conocimiento, Empresas y Universidad de la Junta de Andalucía and FEDER 2014–2020 through the project US-1381045; Universidad de Sevilla. FQM196: Nanotecnología en Superficies y Plasma
Near infrared laser ablation of metals, specifically aluminum, has been systematically applied to generate surface roughness. Very high laser fluences may even lead to a so called “explosive” ablation regime where roughness becomes dramatically enhanced. In the present work we have developed an alternative methodology that, utilizing milder laser irradiation conditions (i.e. laser fluences from 0.37 to 0.72 J/cm²), renders aluminum surfaces with a dual-scale roughness character and Sp parameter values twice or even trice the value found in reference samples. This has been possible for aluminum substrates coated with a highly transparent aluminum oxynitride capping layer. The resulting surfaces, consisting of very rough partially oxidized aluminum with negligible amounts of nitrogen species, resulted highly hydrophobic and depicted long icing delay times as required for anti-icing applications. A correlation has been found between the wetting and anti-icing behaviors, the use of a capping layer and the laser irradiation conditions. To account for this exalted roughening phenomenon, we propose that the transparent capping layer confines the laser energy within the aluminum shallow zones, delays the formation of the plasma plume and produces an enhancement in the aluminum ablation, even at relatively low laser fluences.
Fabrication and characterization of superficially modified porous dental implants
(Elsevier, 2021-02) Trueba Muñoz, Paloma; Navarro Pintado, Carlos; Rodríguez-Ortiz, José Antonio; Beltrán, Ana M.; García-García, Francisco J.; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte; Universidad de Sevilla. Departamento de Ingeniería Mecánica y Fabricación; Universidad de Sevilla. TEP123: Metalurgia e Ingeniería de los Materiales; Universidad de Sevilla. TEP111: Ingeniería Mecánica
Stress-shielding and loosening compromise the success of dental implants under real-life service conditions. This work evaluates the mechanical behavior of superficially modified porous titanium dental implants fabricated by two different routes: conventional powder metallurgy and space-holder techniques. A novel, feasible and repetitive protocol of micro-milling of the implant thread (before sintering), as well as surface modification treatments (after sintering) are also implemented. The discussion is conducted in terms of the influence of porosity and surface roughness on the stiffness and yield strength of implants. The macro-pores concentrate stress locally, and, at the same time, they could act as a barrier to the propagation of micro-cracks. Higher rugosity was observed for virgin implants obtained with spacer particles. Concerning superficially modified implants, while bioglass 1393 was the most effective coating due to its greater infiltration and adhesion capacity, chemical etching could improve osteoblast adhesion because modifies the roughness of the implant surface.
Fe₃ O₄-Au Core-Shell Nanoparticles as a Multimodal Platform for in Vivo Imaging and Focused Photothermal Therapy
(MDPI, 2021-03) Caro Salazar, Carlos; Gámez Márquez, Francisco; Quaresma, Pedro; Páez-Muñoz, José María; Domínguez Moreno, Alejandro; Pearson, John R.; Pernia Leal, Manuel; Beltrán, Ana M.; Fernandez-Afonso, Yilian; Fuente, Jesús M. de la; Franco, Ricardo; Pereira, Eulália; García-Martín, María Luisa; Universidad de Sevilla. Departamento de Química Orgánica y Farmacéutica; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte; Universidad de Sevilla. FQM102: Estereoquímica y Síntesis Asimétrica; Universidad de Sevilla. TEP123: Metalurgia e Ingeniería de los Materiales
In this study, we report the synthesis of gold-coated iron oxide nanoparticles capped with polyvinylpyrrolidone (Fe@Au NPs). The as-synthesized nanoparticles (NPs) exhibited good stability in aqueous media and excellent features as contrast agents (CA) for both magnetic resonance imaging (MRI) and X-ray computed tomography (CT). Additionally, due to the presence of the local surface plasmon resonances of gold, the NPs showed exploitable “light-to-heat” conversion ability in the near-infrared (NIR) region, a key attribute for effective photothermal therapies (PTT). In vitro experiments revealed biocompatibility as well as excellent efficiency in killing glioblastoma cells via PTT. The in vivo nontoxicity of the NPs was demonstrated using zebrafish embryos as an intermediate step between cells and rodent models. To warrant that an effective therapeutic dose was achieved inside the tumor, both intratumoral and intravenous routes were screened in rodent models by MRI and CT. The pharmacokinetics and biodistribution confirmed the multimodal imaging CA capabilities of the Fe@AuNPs and revealed constraints of the intravenous route for tumor targeting, dictating intratumoral administration for therapeutic applications. Finally, Fe@Au NPs were successfully used for an in vivo proof of concept of imaging-guided focused PTT against glioblastoma multiforme in a mouse model.
Green Synthesis of FexOy Nanoparticles with Potential Antioxidant Properties
(MDPI, 2022-07) Abdullah, Johar Amin Ahmed; Jiménez-Rosado, Mercedes; Pérez-Puyana, Víctor Manuel; Guerrero Conejo, Antonio Francisco; Romero García, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química; Universidad de Sevilla (España) CODE 810; Ministerio de Educación y Formación Profesional (España) FPU2017/01718; Universidad de Sevilla. TEP229: Tecnología y Diseño de Productos Multicomponentes
Iron oxide nanoparticles (FexOy-NPs) are currently being applied in numerous high-tech sectors, such as in chemical sectors for catalysis and in the medical sector for drug delivery systems and antimicrobial purposes, due to their specific, unique and magnetic properties. Nevertheless, their synthesis is under continuous investigation, as physicochemical methods are considered expensive and require toxic solvents. Thus, green nanotechnology has shown considerable promise in the eco-biogenesis of nanoparticles. In the current study, FexOy-NPs were synthesized by two different methods: via green synthesis through the use of polyphenols, which were extracted from Phoenix dactylifera L.; and via chemical synthesis, in which the reducing agent was a chemical (NaOH), and iron chloride was used as a precursor. Thus, polyphenol extraction and its ability to produce nanoparticles were evaluated based on the drying temperature used during the Phoenix dactylifera L. recollection, as well as the extraction solvent used. The results highlight the potential of polyphenols present in Phoenix dactylifera L. for the sustainable manufacture of FexOy-NPs. Finally, green and chemical syntheses were compared on the basis of physicochemical characteristics and functional properties.
Heterogeneous data source integration for smart grid ecosystems based on metadata mining
(Elsevier, 2017) Guerrero Alonso, Juan Ignacio; García Delgado, Antonio; Personal Vázquez, Enrique; Luque Rodríguez, Joaquín; León de Mora, Carlos; Universidad de Sevilla. Departamento de Tecnología Electrónica; Ministerio de Economía y Competitividad (MINECO). España
The arrival of new technologies related to smart grids and the resulting ecosystem of applications andmanagement systems pose many new problems. The databases of the traditional grid and the variousinitiatives related to new technologies have given rise to many different management systems with several formats and different architectures. A heterogeneous data source integration system is necessary toupdate these systems for the new smart grid reality. Additionally, it is necessary to take advantage of theinformation smart grids provide. In this paper, the authors propose a heterogeneous data source integration based on IEC standards and metadata mining. Additionally, an automatic data mining framework isapplied to model the integrated information.
Improved strain engineering of 2D materials by adamantane plasma polymer encapsulation
(Nature Research, 2023-03) Carrascoso Plana, ‪Félix; Li, Hao; Obrero Pérez, José M.; Aparicio Rebollo, Francisco Javier; Borrás Martos, Ana Isabel; Island, Joshua O.; Barranco Quero, Ángel; Castellanos-Gómez, Andrés; Universidad de Sevilla. Departamento de Física Aplicada I; Spanish Ministry of Science and Innovation AEI/10.13039/501100011033 grant PID2020-115566RB-I00; Spanish Ministry of Science and Innovation AEI/10.13039/501100011033 grant TED2021-132267B-I00; Spanish Ministry of Science and Innovation AEI/10.13039/501100011033 grant PID2019-110430GB-C21; EU ERDF (FEDER Operational Program (2014-2020) and the Consejería de Economía, Conocimiento, Empresas y Universidad de la Junta de Andalucía grant P18-RT-3480; EU ERDF (FEDER Operational Program (2014-2020) and the Consejería de Economía, Conocimiento, Empresas y Universidad de la Junta de Andalucía grant EMERGIA; EU ERDF (FEDER Operational Program (2014-2020) and the Consejería de Economía, Conocimiento, Empresas y Universidad de la Junta de Andalucía grant US-1381057; Universidad de Sevilla. FQM196: Nanotecnología en Superficies y Plasma
Two-dimensional materials present exceptional crystal elasticity and provide an ideal platform to tune electrical and optical properties through the application of strain. Here we extend recent research on strain engineering in monolayer molybdenum disulfide using an adamantane plasma polymer pinning layer to achieve unprecedented crystal strains of 2.8%. Using micro-reflectance spectroscopy, we report maximum strain gauge factors of −99.5 meV/% and −63.5 meV/% for the A and B exciton of monolayer MoS2, respectively, with a 50 nm adamantane capping layer. These results are corroborated with photoluminescence and Raman measurements on the same samples. Taken together, our results indicate that adamantane polymer is an exceptional capping layer to transfer substrate-induced strain to a 2D layer and achieve higher levels of crystal strain.
Influence of Femtosecond Laser Modification on Biomechanical and Biofunctional Behavior of Porous Titanium Substrates
(MDPI, 2022-04) Beltrán, Ana M.; Giner García, Mercedes; Rodríguez Carballo, Ángel; Trueba Muñoz, Paloma; Rodríguez-Albelo, Luisa Marleny; Vázquez Gámez, María de los Ángeles; Fortio Godinho, Vanda Cristina; Alcudia Cruz, Ana; Amado Paz, José Manuel; López Santos, Carmen; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte; Universidad de Sevilla. Departamento de Citología e Histología Normal y Patológica; Universidad de Sevilla. Departamento de Medicina; Universidad de Sevilla. Departamento de Química Orgánica y Farmacéutica; Universidad de Sevilla. Departamento de Física Aplicada I; Universidad de Sevilla. TEP123: Metalurgia e Ingeniería de los Materiales; Universidad de Sevilla. CTS211: Metabolismo Cálcico, Hipertensión y Arteriosclerosis; Universidad de Sevilla. FQM135: Carbohidratos y Polímeros; Universidad de Sevilla. FQM196: Nanotecnología en Superficies y Plasma
Bone resorption and inadequate osseointegration are considered the main problems of titanium implants. In this investigation, the texture and surface roughness of porous titanium samples obtained by the space holder technique were modified with a femtosecond Yb-doped fiber laser. Different percentages of porosity (30, 40, 50, and 60 vol.%) and particle range size (100–200 and 355–500 μm) were compared with fully-dense samples obtained by conventional powder metallurgy. After femtosecond laser treatment the formation of a rough surface with micro-columns and micro-holes occurred for all the studied substrates. The surface was covered by ripples over the micro-metric structures. This work evaluates both the influence of the macro-pores inherent to the spacer particles, as well as the micro-columns and the texture generated with the laser, on the wettability of the surface, the cell behavior (adhesion and proliferation of osteoblasts), micro-hardness (instrumented micro-indentation test, P–h curves) and scratch resistance. The titanium sample with 30 vol.% and a pore range size of 100–200 μm was the best candidate for the replacement of small damaged cortical bone tissues, based on its better biomechanical (stiffness and yield strength) and biofunctional balance (bone in-growth and in vitro osseointegration).
Influence of the plasticizer on rice bran-based eco-friendly bioplastics obtained by injection moulding
(Elsevier, 2022) Alonso González, María; Félix Ángel, Manuel; Romero García, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química; Ministerio de Ciencia e Innovación (MICIN). España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)
The manufacture of eco-friendly bioplastic materials from renewable resources to replace petroleum-based plastics has attracted increasing attention. For many years, proteins, lipids and polysaccharides have been proposed as natural biopolymers sources to obtain biodegradable plastic materials. As by-product from the rice industry, rice bran, is an available and non-expensive resource of both proteins and starches, food groups that, properly processed, can be employed in the development of bioplastics. Plasticizers are essential for the manufacture of bioplastics and, when carbohydrate/protein mixtures are used, an adequate selection of plasticizers must be addressed. By these means, a material suitable for thermo-mechanical processing methods is obtained if starches are subjected to shear forces under high temperatures and water excess (gelatinisation). Moreover, additional polyol-based plasticizers, such as glycerol and sorbitol, allow obtaining reinforced products with improved elasticity when protein-based bioplastics are processed. The aim of the present study was to analyse the plasticizing effect of water combined with different proportions of glycerol or sorbitol, as well as their influence on the final bioplastic properties. Results indicate that higher water ratios produce stiffer bioplastics with improved viscoelastic moduli, maximum stress and Young´s modulus, while increasing the glycerol and sorbitol content leads to higher elasticities and water uptake capacities in general. Moreover, sorbitol seems to provide more suitable bioplastics with better tensile (up to 500% in Young´s modulus) and functional properties compared to glycerol.
Limits of powder metallurgy to fabricate porous Ti35Nb7Zr5Ta samples for cortical bone replacements
(Elsevier, 2023-06) Rodríguez-Albelo, Luisa Marleny; Navarro González, Paula; Gotor Martínez, Francisco José; Rosa Melián, Julio Ernesto de la; Mena Torres, Danaysi; García-García, Francisco J.; Beltrán, Ana M.; Alcudia Cruz, Ana; Torres Hernández, Yadir; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte; Universidad de Sevilla. Departamento de Química Orgánica y Farmacéutica; MCIN/AEI/10.13039/501100011033/and Junta de Andalucía PID2019-109371 GBI00; Universidad de Sevilla. FQM408: Química Farmacéutica Aplicada; Universidad de Sevilla. TEP123: Metalurgia e Ingeniería de los Materiales
The use of β-Titanium alloys to fabricate metal implants with Young's modulus that resembles bone tissues is presented as an alternative to commercially pure titanium or α-Titanium alloys, although it is still necessary to introduce proper implant porosity to reach the Young's modulus of cortical bones. In this work, porous samples were fabricated by loose sintering (0 MPa) and compared to samples manufactured at 1000 MPa, both sintered under the same conditions. Raw powders and sintered samples of the β-Titanium alloy, Ti35Nb7Zr5Ta, were characterized in detail in terms of both physicochemical and microstructural properties. Moreover, the tribo-mechanical behavior of sintered samples was evaluated by performing ultrasound technique, instrumented micro-indentation (P-h curves), and scratch tests. The bio-functional behavior was studied by impedance spectroscopy and contact angle measurements. The results allowed the evaluation of the limits of conventional powder metallurgy (percentage of porosity, size, and morphology of pores), as well as the influence of the porosity and chemical composition to achieve a better biomechanical and bio-functional behavior that would guarantee bone requirements. The Ti35Nb7Zr5Ta alloy showed relatively high electrical impedance values compared to commercially pure titanium, indicating an improved bio-corrosion behavior. Furthermore, wettability measurements indicated that porous disks fabricated by loose sintering exhibit higher hydrophilicity, often associated with a better antibacterial response.

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