Autores:

Calderón‐Villajos, R., Vázquez‐López, A., Jiménez‐Suárez, A., Sánchez‐Romate, X. X. F., & González-Prolongo, S.

Medio / Año de publicación / Quartile:

Polymer Composites / 2025 / Q1

Resumen:

The self-healing process in PCL (polycaprolactone)/epoxy blends is studied in order to optimize the healing process and understand its underlying mechanism. For this purpose, PCL/epoxy blends are prepared with and without multiwall carbon nanotubes (MWCNTs) addition. Three different self-healing heat-inducement techniques are used (an oven, Joule effect, and infrared (IR) lamp) as a function of healing time (2, 5, 10, and 15 min) and PCL concentration (5, 10, and 15 wt%). The results obtained demonstrate that the addition of MWCNTs to the polymer matrix in PCL/epoxy blends accelerates the self-healing process, attributed to an improved heat diffusion in MWCNTs/PCL/epoxy blends. The best self-healing results were obtained with the highest self-healing time and concentration of PCL, caused by the higher probability of the crack formation over a PCL reservoir. The most efficient techniques to induce the self-healing process in PCL/epoxy blends with and without MWCNTs are the conventional oven and the Joule Effect, respectively, being faster the latter method, as it induces a homogeneous internal heating of the material. Moreover, Joule effect can be controlled remotely, while IR radiation is a noncontact technique, which can be applied in situ. The three heating methods are evaluated considering these factors alongside their energy efficiency, establishing a method to choose a specific heating source for similar systems.

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Autores:

Rigoletto, M., Rapp, M., Arencibia, A., López‐Muñoz, MJ., Tummino, M. L., De Paz, N. F., & Laurenti, E.

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Chem Plus Chem / 2025 / Q2

Resumen:

The presence of potentially toxic elements (PTEs) in drinking water and the food chain is a well-known hazard to human health. Among PTEs, mercury is particularly dangerous for humans and other living organisms due to its wider effects on internal organs. Hg contamination is a critical issue for water bodies used for aquaculture, making its elimination mandatory. Among the techniques proposed for Hg removal, adsorption is advantageous because of its versatility, absence of secondary pollution, and relatively low cost, especially when adsorbents can be obtained from waste materials. In this article, adsorbent materials are synthesized by introducing thiols and primary amino groups into cellulose fibers isolated from soybean hulls. After characterization, the ability of the materials to remove mercury from both ultrapure and aquaculture water solutions is tested. The results confirm the affinity of Hg for thiol groups, leading to the adsorption of 44 mg(Hg)/g in a wide pH range. The amino-modified material adsorbs ≈50% Hg less than the thiol-functionalized one. Test in real water shows that organic matter and salts influence the Hg adsorption process, without affecting the overall efficiency. Finally, in real water, a final concentration below the Hg legal limit for human consumption (1 μg L−1) is found.

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Autores:

Martínez, M., López, R., Rodríguez, J., & Salazar, A. 

Medio / Año de publicación / Quartile:

Theoretical And Applied Fracture Mechanics / 2025 / Q1

Resumen:

Structural integrity of composite solid propellants (CSPs) is one of the main concerns when considering the performance of CSP motors. The development of cracks in the propellant's grain, caused by aging during the service life of the motor, is the main reason for its catastrophic failure. In addition, the fracture characterization of these viscoelastic and highly filled materials is not fully solved yet and hardly addressed for aged CSP. This manuscript presents a broad and comprehensive study on the fracture behavior of aged CSPs, where Schapery's viscoelastic fracture mechanics (VEFM) methodology is used to effectively characterize the fracture behavior of a composite solid propellant with carboxyl-terminated polybutadiene (CTPB) binder. For that, stress relaxation, fracture and tensile tests have been performed on non-aged and aged CSP. Three different accelerated aging methods were employed (mechanical, thermal and ozone) that are related to the phenomena that deteriorate the material during the lifespan of the motor. Two main contributions are derived from this work. The first one is the understanding of the fracture processes developed in aged CSP, under different types of aging. The second most relevant contribution is that the cohesive stress, as the fracture parameter inferred from the VEFM approach, is observed to be correlated to the dewetting stress, a material measurable parameter. The results have potential implications for the design and longevity of future solid rocket propellants.

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Autores:

Vicente-Zurdo, D., Gómez-Mejía, E., Morante-Zarcero, S., Rosales-Conrado, N., & Sierra, I. 

Medio / Año de publicación / Quartile:

Molecules / 2025 / Q1

Resumen:

Recent advancements in analytical strategies have enabled the efficient extraction and characterization of bioactive compounds from agri-food bio-residues, emphasizing green chemistry and circular economy principles. This review highlights the valorization of several agri-food bio-residues for the extraction of high-value-added bioactive compounds, particularly polyphenols, tocopherols, carotenoids, and fatty acids, as a biorefinery approach. To this end, the adoption of environmentally friendly extraction technologies is essential to improve performance, reduce energy consumption, and minimize costs. This study therefore examines emerging methodologies such as supercritical fluid extraction, pressurized liquid extraction, pulsed electric fields, and matrix solid-phase dispersion, highlighting their advantages and limitations. Additionally, the chemical characterization of these bioactive compounds is explored through spectrophotometric and high-resolution chromatographic techniques, crucial for their accurate identification and quantification. This is complemented by an analysis of bioactivity assays evaluating antioxidant, antimicrobial, anticancer, neuroprotective, and anti-inflammatory properties, with a focus on their applications in the food, pharmaceutical, and cosmetic industries. However, the analytical control of toxic compounds, such as alkaloids, in these bio-residues is undoubtedly needed. Ultimately, this approach not only promotes sustainability but also contributes to the development of eco-friendly solutions in various industries.

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Autores:

Vera-Baquero, F. L., Gañán, J., Casado, N., Pérez-Quintanilla, D., Morante-Zarcero, S., & Sierra, I.

Medio / Año de publicación / Quartile:

Foods / 2025 / Q1

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Rice husk (RH), a globally abundant agri-food waste, presents a promising renewable silicon source for producing SBA-15 mesoporous silica-based materials. This study aimed to synthesize and bifunctionalize SBA-15 using RH as a silica precursor, incorporating sulfonic and octadecyl groups to create a mixed-mode sorbent, RH-SBA-15-SO3H-C18, with reversed-phase and cation exchange properties. The material's structure and properties were characterized using advanced techniques, including X-ray diffraction, infrared spectroscopy, N2 adsorption–desorption isotherms, nuclear magnetic resonance, and electron microscopy. These analyses confirmed an ordered mesoporous structure with a high specific surface area of 238 m2/g, pore volume of 0.45 cm3/g, pore diameter of 32 Å, and uniform pore distribution, highlighting its exceptional textural qualities. This sorbent was effectively utilized in solid-phase extraction to purify 29 alkaloids from three families—tropane, pyrrolizidine, and opium—followed by an analysis using ultra-high performance liquid chromatography coupled to ion-trap tandem mass spectrometry. The developed analytical method was validated and applied to gluten-free bread samples, revealing tropane and opium alkaloids, some at concentrations exceeding regulatory limits. These findings demonstrate that RH-derived RH-SBA-15-SO3H-C18 is a viable, efficient alternative to commercial sorbents for monitoring natural toxins in food, offering a sustainable solution for repurposing agri-food waste while addressing food safety challenges.Keywords: rice husk; bifunctionalized SBA-15; solid-phase extraction; tropane alkaloids; pyrrolizidine alkaloids; opium alkaloids; multifamily analytical methodology; food control.

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Autores:

Carena, L., García-Gil, Á., Marugán, J., & Vione, D.

Medio / Año de publicación / Quartile:

Foods / 2025 / Q1

Resumen:

Photochemical mineralisation is an abiotic process by which the organic matter in natural waters, which is mostly dissolved, is eventually transformed into CO2 by the action of sunlight. The process has important implications for global C cycling, the penetration of sunlight into the water column, photochemical reactions, and microbial processes. Here we applied an approximated photochemical model to assess the extent of CO2 photogeneration by mineralisation of dissolved organic matter in lakes located between 60°S and 60°N latitude. The results suggest that, although lake-water organic matter would usually undergo faster photomineralisation in the tropical belt than elsewhere, by far the highest contributions to the photochemical production of CO2 would come from lakes located between 30°N and 60°N latitude. In particular, of the ~7 × 104 lakes we selected for the study, around 50 % of CO2 photogeneration would be accounted for by just 7 large lakes, of which only one is located in the tropical belt. It appears that the lake surface is a very important factor that affects the overall photomineralisation potential of dissolved organic matter.

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Autores:

Vera-Baquero, F. L., Pérez-Quintanilla, D., Morante-Zarcero, S., & Sierra, I.

Medio / Año de publicación / Quartile:

Food Chemistry / 2025 / Q1

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A sample preparation procedure for the analysis of tropane alkaloids (atropine and scopolamine) in multigrain cereal-based baby products (MGBP) has been optimized in this study. The protocol was based on a solid-liquid extraction, followed by purification by solid-phase extraction with MCM-41 functionalised with sulphonic acid groups as sorbent, before the analysis by ultra-performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry. The method was successfully validated with limits of quantification of 0.005 and 0.05 μg/kg for atropine and scopolamine, respectively. The analysis of a quality control material (TAs in baby food multigrain) demonstrated the suitability for the purpose of the methodology. The analysis of twenty commercial MGBP (mixtures of 2 to 10 cereal flours, with honey, milk, fruit pulp or juices) purchased between 2016 and 2024, revealed the presence of atropine (between 0.07 and 1.0 μg/kg) and scopolamine (between 0.15 and 12 μg/kg) in all the MGBP analysed.

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Autores:

Salazar, A., Martínez, M., Reinhards, C., Rico, A., & Rodríguez, J.

Medio / Año de publicación / Quartile:

Engineering Fracture Mechanics / 2025 / Q1

Resumen:

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Autores:

González-Banciella, A., Martinez-Diaz, D., Kundu, M., Sánchez, M., & Ureña, A.

Medio / Año de publicación / Quartile:

Autores:

Collado, I., Vázquez-López, A., Heredia, S., De la Vega, J., Jiménez-Suárez, A., Maestre, D., & González Prolongo, S.

Autores:

Moya, A., Sánchez-Fuente, M., Linde, M., Cepa-López, V., Del Hierro, I., Díaz-Sánchez, M., Gómez-Ruiz, S., & Mas-Ballesté, R. 

Autores:

Vera-Baquero, F. L., Morante-Zarcero, S., Pérez-Quintanilla, D., & Sierra, I. 

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Autores:

Landazábal, F. J., Ventura, M., Paniagua, M., Melero, J. A., & Morales, G.     

Medio / Año de publicación / Quartile:

Increasing carbon dioxide gas emissions in the aviation industry, together with the depletion of fossil fuel sources, are serious issues that require researchers to develop bio-jet fuel from sustainable renewable sources. A promising approach is the use of highly abundant and economic lignocellulosic waste biomass, from which furanic compounds can be derived. However, to obtain C9-C15 jet fuel-compatible products, C-C coupling strategies are mandatory to increase the chain length of the furanic platforms. Furthermore, there exists an uncovered potential for integrating fermentation-derived platforms, like acetoin, in advanced bio-jet fuel production routes. In this sense, this work explores the C-C coupling of acetoin, a fermentation-derived molecule, with 2-methylfuran (2-MF), a lignocellulose-derived molecule that can be obtained from selective hydrogenolysis of furfural, via hydroxyalkylation/alkylation (HAA). This solvent-free acid-catalyzed reaction yields oxygenated adducts incorporating one molecule of acetoin and 1-3 molecules of 2-MF (9–19 C atoms) that display high potential as bio-jet fuel precursors. However, side reactions are also present, coming from the auto-condensation of acetoin and/or 2-MF, yielding heavier or more oxygenated undesired compounds, so that selectivity appears as the key parameter in the catalyst performance. In this work, sulfonic acid-based resin Amberlyst-15 has displayed high activity and selectivity towards the most interesting di-condensed C14 compound, herein denoted as Ac(MF)2, which evidences the benefits of applying strong Brønsted acid sites allocated within a polymer matrix in high surface concentration. The optimization of the reaction conditions, assessed with the help of response surface methodology, led to over 77 % yield to Ac(MF)2 with acetoin conversion around 90 %, under the optimized reaction conditions (60 °C, 2-MF/acetoin = 2.5 (mol), 6 h, catalysts loading 20 wt% referred to acetoin). Amberlyst-15 catalyst was tested in a 5-cycle reusability experiment, keeping an acceptable level of catalytic activity and selectivity despite evidence of fouling due to the formation of organic deposits. These results pave the way for a new route of bio-jet fuel production starting from already established biomass-derived platform molecules.

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Autores:

Díaz‐Mena, V., Sánchez‐Romate, X. X. F., Sánchez, M., & Ureña, A.     

Medio / Año de publicación / Quartile:

Wearable electronics have gained increasing attention due to their potential in real-time health monitoring applications. However, the environmental impact and waste associated with non-recyclable materials used in these devices remain critical challenges. This study investigates the reprocessing and recyclability of flexible strain sensors based on Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) nanocomposites reinforced with carbon nanotubes (CNT) and graphene nanoplatelets (GNP). The nanocomposites are subjected to multiple recycling cycles using a solvent casting method, and their electrical and electromechanical properties are thoroughly analyzed. Microstructural characterization revealed improved nanoparticle dispersion with recycling, albeit with distinct behavior for CNT and GNP due to differences in aspect ratio and geometry. Electrical tests demonstrated a reduction in conductivity for CNT-based sensors due to nanoparticle breakage, while GNP-based sensors exhibited stable conductivity. Electromechanical tests indicated enhanced sensitivity after recycling, with GNP-based sensors showing superior robustness. Proof-of-concept tests, including monitoring knee joint movements and breathing patterns, validated the functionality of recycled sensors in health monitoring applications. The findings highlight the potential of reprocessed PVDF-HFP nanocomposite sensors as sustainable, high-performance materials for wearable electronics.

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Autores:

Fernández-Pintor, B., Gañán, J., Pérez-Quintanilla, D., Morante-Zarcero, S., & Sierra, I.

Medio / Año de publicación / Quartile:

A spherical ordered mesoporous silica functionalized with octadecylsilane ligand (SM-C18) was successfully synthesized and characterized, showing 647 m2/g of surface area, 45 Å of pore size, 4–6 μm of particle diameter and 0.37 mmol/g of functionalization degree. 1.5 mg of SM-C18 were packed into EPREP micro-solid phase extraction (µSPEed) cartridges for use with a handheld programmable digital analytical syringe (digiVOL®) to develop a sample preparation protocol for the analysis of two tropane (TAs) and twenty-one pyrrolizidine (PAs) alkaloids. The SM-C18 demonstrated greater retention capacity compared with commercial C18/hydrophilic amorphous silica sorbent. The optimized extraction conditions were as follows: 100 µL of methanol (2 cycles) and 100 µL of H2O (2 cycles) for conditioning, 100 µL of H2O-reconstituted sample (10 cycles), for a total of 1 mL of sample loaded, and 100 µL of methanol (2 cycles) for elution, followed by subsequent analysis by UHPLC-MS/MS. The method was successfully validated, showing good recoveries ranging between 91 and 97 %, low quantification limits and absence of matrix effect for the twenty-tree alkaloids. Additionally, cartridges packed with SM-C18 material allow for better reusability compared to the commercial material, as it has been demonstrated that they can be used for at least 75 extractions. This significantly enhances the method's sustainability. Finally, it was applied to 25 samples of flower extract supplements (FES). In two different batches of the sample obtained from Convolvulus arvensis flowers (FES4a and FES4b), atropine and scopolamine were quantified.

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Autores:

Sirvent, P., Lozano, A., Garrido-Maneiro, M. A., Poza, P., Vaz, R. F., Albaladejo-Fuentes, V., & Cano, I. G.

Medio / Año de publicación / Quartile:

Additive manufacturing, and particularly the cold spray technology for additive manufacturing (CSAM), is fast becoming a key technology to produce components in an efficient and environmentally friendly manner. This method usually requires a final rectification to generate specific surface topographies. The novelty of this paper is related to the capabilities of the CSAM technique to control the surface topography of the samples. Thus, this work investigates the topography of CSAM samples and its correlation with the processing parameters. Pure Al and Ti samples were manufactured following two different deposition strategies: traditional and metal knitting. This last strategy constitutes a promising alternative for CSAM to obtain near-net-final shape components. The topography was analyzed by confocal microscopy considering the form, waviness, and roughness components. Moreover, the microstructure and mechanical properties of the samples were also investigated in order to assure reliable freestanding CSAM deposits. Results showed that the waviness was controlled by the spraying line spacing, and that the waviness and roughness profiles of the metal knitting samples presented the largest wavelengths regardless the material. The metal knitting method generated samples with higher thickness and porosity than the traditional strategy, while the mechanical properties at the local scale were not varied. The study highlights the CSAM technology potential for controlling the deposit's surface topography.

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Autores:

Artigas‐Arnaudas, J., Sánchez, M., & Ureña, A.

Medio / Año de publicación / Quartile:

One potential solution to the problem of energy storage in certain transportation vehicles is the development of multifunctional materials. Specifically, structural supercapacitors offer a combination of mechanical strength and energy storage capabilities, which could replace vehicle components and reduce overall vehicle weight. However, structural electrodes made from carbon fiber face a significant limitation due to their low specific surface area. This study examines the direct synthesis of metal-organic frameworks on the surface of carbon fibers. Structures such as ZIF-8 and ZIF-L can be easily synthesized from the same metal-organic precursors and exhibit high surface areas, making them ideal for this application. Both ZIF structures form a continuous coating on the carbon fiber, increasing the specific surface area of the electrodes. For the ZIF-8 structure, the coating achieves a thickness of 1 μm and a specific surface area of 30.24 m2/g. In contrast, the sheet-like geometry of the ZIF-L results in greater thicknesses, though with a lower specific surface area of only 0.7 m2/g. The potential use of these electrodes in supercapacitor devices has been demonstrated through the assembly of structural supercapacitors with a polymeric solid electrolyte. The supercapacitor with ZIF-8 electrodes has achieved a specific capacitance of 7.78 mF/g. Despite the limitations associated with internal resistance, all structural electrodes have shown stability over charge and discharge cycles.

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Autores:

Molina, C., Abdrassilova, A., Ávila, M., Alonso-Doncel, M., Cueto, J., Gómez-Pozuelo, G., Briones, L., Botas, J., Serrano, D., Peral, A., & Escola, J.

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The preparation of hierarchical USY zeolite, exhibiting uniform mesoporosity and high Si/Al atomic ratio (48–52), has been investigated by means of a surfactant/ammonia post-treatment applied to a commercial USY sample. The procedure involved the use of temperatures within 40–135 °C, a low ammonia concentration solution (0.05 N) and hydrothermal synthesis times of 20 h. When working at 40–80 °C, the obtained USY samples exhibit enhanced intraparticular mesoporosity (324–418 m2 g−1), showing increasingly uniform mesopores around 4.0 nm, while holding a remarkable zeolitic microporosity (413–363 m2 g−1). In contrast, higher temperatures resulted in a steady abatement of crystalline zeolitic domains, with a total collapse of the zeolite structure at 135 °C. These hierarchical USY materials were tested in the alkylation of phenol with isopropanol, wherein one of the obtained products, e.g. 2,6-diisopropylphenol (Propofol), is the most important intravenous anaesthetic in the market. Interestingly, the generation of the uniform mesoporosity in USY samples led to an enhancement of both the phenol conversion and the selectivity towards C-alkylation products. Thus, the sample treated at 60 °C (USY-60) gave rise to the highest selectivity towards C-alkylation products (84 %) and poly-alkylphenols formation (72 %), with an encouraging selectivity towards 2,6-diisopropylphenol (43 %).

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Autores:

Uricochea, N., Uzquiano, V., Paniagua, M., Morales, G., & Melero, J. A.

Medio / Año de publicación / Quartile:

The high potential of using levulinic acid and furfural as platform molecules for the production of oxygenated adducts suitable as precursors for SAF synthesis is studied through the aldol condensation of both molecules. The research is the first-time demonstration of solventless acid-catalysed levulinic acid/furfural aldol condensation. The catalytic performance of a commercial H-USY zeolite and two post-synthetic variations thereof, with different dealumination degree and Zr loading, is analyzed, aiming at tuning the acid catalytic properties. The catalyst with an almost complete Al removal accompanied by the highest Zr wt% (Zr-USY-2) gave the best results in terms of selective conversion of furfural, pointing out to the Lewis acid sites as the main active sites to promote the aldol condensation reaction. An experimental design allowed to identify the optimal LA/FAL molar ratio (9/1) and reaction temperature (140 °C), while catalyst loading presented a minor significance. The optimization of the reaction parameters allowed to achieve a maximum furfural conversion of 88 %, combined with a yield towards the desired C10 adducts of 55 %. Furthermore, despite the catalytic performance of this material is slightly impaired in consecutive reaction cycles, it can be recovered with a thermal regeneration step, indicating a good reusability.

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Lorero I, Rodríguez Á, Campo M, González-Prolongo S.

Revista: Polymers

Año de publicación: 2023

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