Artículos de revista DCIE - ZIES Aldizkari artikuluak

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Open Access
Synergic removal of Aflatoxin B1 in oily matrices by focusing on the peroxidase-like nanozymes-driven strategies: mechanisms and intermediate toxicity, nutritional impact, advances and challenges
(Elsevier, 2025-09-01) Faraji, Ali Reza; Gil Bravo, Antonio; Farahanipour, Alireza; Tehrani, Elnaz; Khoramdareh, Niloufar Bakhshi; Dashtabadi, E.; Jafari, Seyede Zeynab; Shojaei, Najmeh; Hekmatian, Zahra; Saeedi, S.; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Background: oilseeds and extracted oils, as the supplier of at least 40 % of calories, dietary essential fatty acids, and food flavor, due to insufficient cultivation-harvesting techniques, processing and long-term storage in improper conditions, and lack of adequate food-safety standards and/or official consideration, are prone to contamination by AFB1. Given its irreversible adverse effects on consumer health and food/feed safety due to various factors (e.g., high chemical stability of lipophilic AFB1, transformation to other toxic derivatives, and chemical interaction with oily matrices), developing a decontamination approach from a safety/efficiency perspective is imperative. Scope and approach: this review provides the recent progress on the AFB1 detoxification from oily matrices by focusing on the peroxidase-based nanozymes technologies and enzymatic-like mechanisms of reactive species in detail for the first time. Significantly, the superiority of enzymatic-like activity in capturing/detoxifying AFB1 from oily matrices, change in nutritional quality, organoleptic profiles, and physicochemical properties of oils, and mechanism of action are highlighted by a comparison with various edible oil remediation systems (i.e., physicochemical, physical, chemical, and biological). Key findings and conclusions: The peroxidase nanozyme-based technologies could be of primary importance in the remediation of AFB1 from oily matrices due to the unique merits of nanozymes (e.g., low-cost, size/surface-dependent properties, excellent efficiency and durability/stability, recoverability, biocompatibility, many capabilities to maintain the nutritional quality, and without require to any pre-treatment). Finally, this review aimed to provide several beneficial insights regarding safety, universality, finance, ecology, rapidity, selectivity, detoxification path, and toxicity/biological nature of transformed products in peroxidase-mimicking nanozyme technologies.
Open Access
Synthesis of MOF@aluminum saline slag-based composites for CO2 capture at moderate temperatures
(Elsevier, 2025-09-01) Muñoz Alvear, Helir Joseph; Vicente, Miguel Ángel; Korili, Sophia A.; Gil Bravo, Antonio; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa; Gobierno de Navarra / Nafarroako Gobernua
Combining metal–organic framework (MOF) materials and aluminum-containing saline slag residues opens a promising research avenue. This approach reduces the environmental impact of aluminum production by integrating industrial waste in the development of advanced materials that adhere to circular economy principles. It also addresses some inherent stability issues observed in pure MOFs. This study is the first to propose the use of this industrial by-product as a cost-effective and environmentally friendly modulator for controlling the phase transition between MIL-96(Al) and MIL-110(Al). For the first time, novel MOFs composites (MOF@RW1*-n; n = 25, 50, 75% waste) and saline slag waste (RW1*)—a by-product of initial aluminum extraction in an acidic medium—were synthesized in situ by preparing the MOF on RW1* via hydrothermal treatment and subsequently tested as CO2 adsorbents at up to 225 ◦C and 80 kPa. The optimized RW1* content in the composite proved critical in determining the formation of specific crystalline structures (MIL-96(Al) or MIL-110(Al)), ultimately yielding hybrid materials with enhanced textural properties and thermal stability.
Open Access
High-temperature superspin glass and low-temperature glassy exchange bias in passivated FeCo nanoparticles
(Elsevier, 2025-05-15) López Martín, Raúl; Lepesant, Mathieu; Lacroix, Lise-Marie; Toro, José A. de; López Ortega, Alberto; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Conventional powders, dense systems of magnetic nanoparticles, often combine intra- and inter-particle magnetically glassy properties, which may complicate their interpretation. To shed light on this matter, we have studied 9 nm FeCo particles synthesized by thermal co-decomposition of metal amides after a passivation layer around 2 nm thick has formed in ambient conditions. The saturation magnetization, 117 emu/g, is consistent with the above metallic core/ferrite shell picture. The high magnetic moment and concentration of the particles yield, via strong interparticle interactions, a remarkable room temperature superspin glass-like phase (with freezing temperature above 350 K) for such small particles, as confirmed by the de Almeida-Thouless analysis. Additionally, we detect a spin glass-like freezing at the atomic scale (within the particles). Its corresponding feature, a small hump under small fields in the temperature dependence of the magnetization, closely agrees with the onset of the exchange bias effect (∼ 60 K) measured, unlike it is customary, with repeated field-coolings. The spin-disordered nature of the core/shell interface is further proved by a strong training effect of the exchange bias field, among others. This magnetic behavior offers an indirect proof of structural interface disorder even in fully passivated metallic particles.
Open Access
Ferrihydrite surface functionalization of anatase TiO2 nanoparticles as flower-like core-shell heterostructure with enhanced visible-light-driven photocatalytic properties
(Elsevier, 2025-07-15) Gherca, Daniel; Borhan, Adrian Iulian; Herea, Daniel-Dumitru; Minuti, Anca Emanuela; Stavila, Cristina; Danceanu, Camelia Mihaela; Popescu, Dana-Georgeta; Borca, Camelia Nicoleta; Huthwelker, Thomas; Stoian, George; Chiriac, Horia; Gómez Polo, Cristina; Ababei, Gabriel; Lupu, Nicoleta; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
The development of titania-based hybrid nanostructures with enhanced visible-light photocatalytic activity has been a key research area recently. The present study addresses current limitations of the TiO2 based composite photocatalyst by newly-experimental designing of flower-like multifunctional hybrid nanostructure with visible light capability through Ferrihydrite (Fh) surface TiO2 functionalization. Here, we present a versatile nanocompartimentalization process of which, core anatase TiO2 nanoparticles are emebeded into Fh lamellar shell. Physico-chemical properties related to the chemical structure and morphology of the prepared nanomaterials were comprehensively analysed using complementary analytical techniques, such as powder X-Ray Diffraction (XRD), Field-Emission Scanning Electron Microscopy (FE-SEM), Ultra-High Resolution Transmission Electron Microscopy (UHR-TEM), X-Ray Photoelectron Spectroscopy (XPS) and soft X-Ray Absorption Spectroscopy (XAS). The conducted visible-light-driven photocatalytic water splitting tests highlights significant enhancement in the Oxygen Evolution Reaction (OER) performance for TiO2-Fh core-shell nanoheterostructure of 25.6 μmol/L of molecular oxygen after 60 min of visible light irradiation (AM1.5G), and a photocatalytic water oxidation activity rate of 341.3 μmol l-1 g-1h-1. The biocompatibility assessment of the developed core-shell structures combined with their enhanced photocatalytic water oxidation activity under visible light illumination suits them as excellent candidates for the development of sustainable environmental remediation technologies.
Open Access
Low-cost Titania-Hydroxyapatite (TiHAp) nanocomposites were synthesized for removal of methylene blue under solar and UV irradiation
(Elsevier, 2025-07-01) Latifi, Souhayla; Saoiabi, Sanaa ; Alanazi, Mohammed M. ; Boukra, Omar ; Krime, Anas ; El Hammari, Larbi; Azzaoui, Khalil; Hammouti, Belkheir; Hanbali, Ghadir; Jodeh, Shehdeh; Saoiabi, Ahmad ; Sabbahi, Rachid ; Algarra González, Manuel; Abidi, Noureddine ; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
Water pollution from industrial dyes like methylene blue (MB) poses significant environmental and health risks due to their toxicity and persistence. In this study, we synthesized a novel titania-hydroxyapatite (TiHAp) nanocomposite via a low-cost, scalable sol-gel method to address these challenges. The composite was comprehensively characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area analysis, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Photocatalytic degradation of MB under both solar and UV irradiation was evaluated using kinetic (pseudo-first-order and pseudo-second-order) and isotherm (Langmuir and Freundlich) models, demonstrating hydroxyapatite's key role in enhancing adsorption and facilitating effective interactions with the catalyst. Under optimized conditions, the TiHAp nanocomposite achieved 96.58 % degradation of MB at an initial concentration of 120 mg/L and retained over 95 % activity after five reuse cycles. These results illustrate that the synergistic combination of TiO₂'s photocatalytic activity and HAp's adsorptive capacity produces a highly effective composite for degrading organic pollutants. The study underscores the potential of TiHAp nanocomposites as sustainable materials for wastewater treatment applications, while future work will explore their performance against a broader range of contaminants under realistic environmental conditions.
Open Access
Livestock and water resources: a comparative study of water footprint in different farming systems
(MDPI, 2025-03-05) Arrien, María Macarena; Martínez Aldaya, Maite; Rodríguez, Corina Iris; Ciencias; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
Livestock production systems are major consumers of freshwater, potentially compromising the sustainability of water resources at production sites. The water footprint (WF) quantifies the water consumed and polluted by a product or service. The aim of this study was to evaluate the WF of steer production from the cradle to the farm gate in representative intensive, extensive, and mixed farms located in the southeast of Buenos Aires province, Argentina. The WF to produce a live steer varied between 4247 and 5912 m3/animal. The extensive system contains the highest green WF but is also the most sustainable compared to industrial and mixed productions since it does not have an associated pollutant load or blue water. This work is the first approach to calculating the WF of live steers in Argentina carried out with local and detailed data and focuses on grey WF related to nitrogen leaching from effluents in intensive systems, showing that the blue and grey footprints increase as production intensifies. The information may be relevant for consumers and producers to make more informed decisions. Furthermore, it is essential for governments to promote sustainable practices in livestock farming, recognizing the dependence on water resources both domestically and throughout international supply chains, in order to assess their environmental policies and ensure national food security.
Open Access
Drought stress modifies the source-sink dynamics of nitrogen-fixing soybean plants prioritizing roots and nodules
(Wiley, 2025-05-26) Rubia Galiano, María Isabel; Larrainzar Rodríguez, Estíbaliz; Arrese-Igor Sánchez, César; Ciencias; Zientziak; Institute for Multidisciplinary Research in Applied Biology - IMAB; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Soybean plants are one of the most cultivated legume crops worldwide. Their ability to establish nitrogen-fixing symbiosis with rhizobium bacteria allows the reduction of molecular nitrogen to ammonium, contributing to a reduction in the dependence on nitrogen fertilizers. However, nitrogen fixation is highly sensitive to environmental stresses, such as water deficit, and the regulatory mechanisms underlying this inhibition remain debatable. In the current study, we analyzed carbon (C) allocation dynamics in drought-stressed soybean plants following the application of [U-C-13]-sucrose to source leaves. Three sets of plants were analyzed: well-watered plants, mild drought, and severe drought-stressed plants. C-13 distribution was monitored for up to 6 h post-application. Under optimal water conditions, C-13 was mainly allocated to young (sink) leaves. During drought stress, transport trends changed, prioritizing C allocation primarily to the roots and nodules to a lesser extent. Metabolite profiling identified drought- and tissue-specific variations in the levels of the major C and N compounds.
Open Access
Low temperature chemical looping combustion of pyrolysis gases in a fixed bed reactor
(Elsevier, 2025-08-01) Gracia Monforte, César; Maldonado-Martín, Francisco; Atienza Martínez, María; Ábrego, Javier; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa; Gobierno de Navarra / Nafarroako Gobernua
This study presents an experimental investigation into the feasibility of oxidizing biomass pyrolysis gases at relatively low temperatures using a chemical looping combustion (CLC) approach. The application of this alternative method would enable the capture of carbon from the pyrolysis gas stream, which is currently released into the atmosphere in most pyrolysis systems, as high-purity CO2. In a fixed bed reactor, the reduction behavior of three different Cu-based oxygen carriers (OC) - pure CuO pellets, carulite and Al2O3-supported CuO - was evaluated to determine whether pyrolysis gases could be completely oxidized to CO2 and H2O within a temperature range of 600–650 ◦C and at weight hourly space velocities (WHSV) of 0.06–0.10 h− 1 . Both CuO and carulite exhibited significant amounts of unconverted pyrolysis gases even during the initial stages of the reduction experiments. In contrast, Al2O3-supported CuO emerged as the most effective material, facilitating the complete oxidation of pyrolysis gases over extended reaction times. For this oxygen carrier, a decline in the combustion efficiency was only observed at very high (90 %) reduction conversions. Reduction/oxidation cycles for this most promising material were successfully demonstrated, with the oxygen carrier showing no signs of activity loss after 10 cycles. However, carbon deposition was detected under several experimental conditions, which could potentially reduce the carbon capture efficiency of the process.
Open Access
Drought limits tree growth more than greenness and reproduction: insights from five case studies in Spain
(KeAi Communications, 2025-08-01) Camarero, Jesús Julio; Rubio-Cuadrado, Álvaro; González de Andrés, Ester; Valeriano, Cristina; Pizarro, Manuel; Imbert Rodríguez, Bosco; Lo, Yueh-Hsin; Blanco Vaca, Juan Antonio; Ciencias; Zientziak; Institute for Multidisciplinary Research in Applied Biology - IMAB
Droughts impact forests by influencing various processes such as canopy greenness, tree growth, and reproduction, but most studies have only examined a few of these processes. More comprehensive assessments of forest responses to climate variability and water shortages are needed to improve forecasts of post-drought dynamics. Iberian forests are well-suited for evaluating these effects because they experience diverse climatic conditions and are dominated by various conifer and broadleaf species, many of which exhibit masting. We assessed how greenness, evaluated using the normalized difference vegetation index (NDVI), tree radial growth, and seed or cone production responded to drought in five tree species (three conifers: silver fir (Abies alba), Scots pine (Pinus sylvestris), and stone pine (Pinus pinea); two broadleaves: European beech (Fagus sylvatica) and holm oak (Quercus ilex) inhabiting sites with different aridity. We correlated these data with the standardized precipitation evapotranspiration index (SPEI) using the climate window analysis (climwin) package, which identifies the most relevant climate window. Drought constrained growth more than greenness and seed or cone production. Dry conditions led to high seed or cone production in species found in cool, moist sites (silver fir, beech, and Scots pine). We also found negative associations of cone production with summer SPEI in the drought-tolerant stone pine, which showed lagged growth−cone negative correlations. However, in the seasonally dry holm oak forests, severe droughts constrained both growth and acorn production, leading to a positive correlation between these variables. Drought impacts on greenness, growth, seed, and cone production depended on species phenology and site aridity. A negative correlation between growth and reproduction does not necessarily indicate trade-offs, as both may be influenced by similar climatic factors.
Open Access
Nitrogen fertilization form and energetic status as target points conditioning rice responsiveness to elevated [CO2]
(Frontiers Media, 2025-03-11) Jáuregui Mosquera, Iván; Mitsui, Toshiaki; Gakière, Bertrand; Mauve, Caroline; Gilard, Françoise; Aranjuelo Michelena, Iker; Baslam, Marouane; Ciencias; Zientziak
The nitrogen (N) fertilization form and plant energy status are known to significantly influence plant responses to elevated atmospheric carbon dioxide (CO2) concentrations. However, a close examination of the interplay between N sources under contrasting light intensity has been notably absent in the literature. In this study, we conducted a factorial experiment with rice plants involving two different light intensities (150 and 300 µmol m-2 s-1), inorganic N sources [nitrate (N-NO3) or ammonium nitrate (N-NH4NO3)] at varying CO2 levels (410 and 700 parts per million, ppm). The aim was to examine the individual and combined effects of these factors on the allocation of biomass in whole plants, as well as on leaf-level photosynthetic characteristics, chloroplast morphology and development, ATP content, ionomics, metabolomics, and hormone profiles. Our research hypothesis posits that mixed nutrition enhances plant responsiveness to elevated CO2 (eCO2) at both light levels compared to sole N-NO3 nutrition, due to its diminished energy demands for plant assimilation. Our findings indicate that N-NO3 nutrition does not promote the growth of rice, its photosynthetic capacity, or N content when exposed to ambient CO2 (aCO2), and is significantly reduced in low light (LL) conditions. Rice plants with N-NH4NO3 exhibited a higher carboxylation capacity, which resulted in larger biomass (total C, tiller number, and lower root-shoot ratio) supported by higher Calvin-cycle-related sugars. The lower leaf N content and overall amino acid levels at eCO2, particularly pronounced in N-NO3, combined with the lower ATP content (lowest at LL and N-NO3), may reflect the higher energy costs of N assimilation at eCO2. We also observed significant plasticity patterns in leaves under eCO2. Our findings highlight the importance of a thorough physiological understanding to inform innovative management practices aimed at mitigating the negative effects of climate change on plant N use efficiency.
Open Access
Carbon and water footprints of the revalorisation of glucosinolates from broccoli by-products: case study from Spain
(Elsevier, 2025-05-01) González Peñalver, José Miguel; Martínez Aldaya, Maite; Muez, Ane Maite; Martín-Guindal, Andrea; Beriain Apesteguía, María José; Agronomía, Biotecnología y Alimentación; Agronomia, Bioteknologia eta Elikadura; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Ciencias; Zientziak; Gobierno de Navarra / Nafarroako Gobernua
Assessing the costs, benefits, and externalities of circular economy measures from a life cycle perspective is increasingly important for developing sustainable agro-food strategies. This study evaluates the carbon and water implications of revalorising glucosinolates from broccoli by-products through two distinct life-cycle scenarios in a case study conducted in Navarra, Spain. In the first scenario, glucosinolates are obtained from conventional broccoli production, where they are naturally present in the edible inflorescences. The second scenario introduces an innovative step: extracting glucosinolates from otherwise discarded broccoli by-products, such as stalks and inflorescence detachments. Carbon and water footprints were analysed for both scenarios based on the production of 1000 grams of glucosinolates. The results reveal that while the second scenario enhances resource efficiency by utilizing agricultural waste, the environmental costs of the extraction process outweigh the benefits, leading to a 37.6 % increase in greenhouse gas emissions and a 4.6 % rise in water usage compared to the first scenario. To address this, an improvement scenario is proposed, featuring a more efficient use of solvents during extraction, which significantly reduces both emissions and water use. This study underscores that circular economy strategies in agro-food systems do not always translate into environmental benefits accross all resources. A detailed analysis of various carbon and water indicators has provided valuable insights to enhance the environmental performance of such strategies, reinforcing the importance of life-cycle assessments in shaping more effective agro-food policies.
Open Access
Complementary strengths of water footprint and life cycle assessments in analyzing global freshwater appropriation and its local impacts: recommendations from an interdisciplinary discussion series
(Elsevier, 2025-05-01) Berger, Markus; Gerbens-Leenes, Winnie; Karandish, Fatemeh; Martínez Aldaya, Maite; Boulay, Anne-Marie; Hogeboom, Rick J.; Link, Andreas; Manzardo, Alessandro; Mialyk, Oleksandr; Motoshita, Masaharu; Nuñez, Montserrat; Pfister, Stephan; Rosenbaum, Ralph K.; Scherer, Laura; Su, Han; Wöhler, Lara; Ciencias; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
Considering globally increasing water challenges, the analysis of water use along supply chains is of great relevance and can be tackled by mainly two methodological approaches: Water Footprint Assessment (WFA) and Life Cycle Assessment (LCA). While sharing the same goal of promoting sustainable water use, both methods developed in different contexts and scientific communities. This has led to heated debates on methodological presuppositions that at times has become unconstructive. To build mutual understanding and enable a fruitful cooperation, researchers from both communities have exchanged over the course of two years. This paper summarizes the outcomes of this discussion series by providing i) a description of the development of both approaches and their ways of assessing freshwater consumption and pollution, ii) an application in a case study, and iii) an analysis of strengths and weaknesses in relation to questions decision-makers may have. Our analysis revealed that WFA's strength lies in its ability to measure freshwater appropriation, water-use efficiency, water scarcity and total pollution levels. This makes WFA particularly useful for crop selection as well as agricultural and river basin water management. With its focus on assessing impacts, LCA is strong in quantifying potential consequences of water use for humans and ecosystems. This makes it particularly useful for assessing complex supply chains and for analysing water-related impacts in combination with other environmental aspects. Rather than being in competition with each other, we emphasize the individual and complementary strengths of both approaches and their joint efforts in addressing the world's pressing water challenges.
Open Access
Enhancement of sol-gel coatings for photoprotection of rosé wines
(MDPI, 2025-02-15) Moriones, Jennifer; Osés Martínez de Zúñiga, Javier; Amézqueta, Pablo; Palacio, José F.; Fernández de Ara, Jonathan; Almandoz Sánchez, Eluxka; Ciencias; Zientziak; Ingeniería; Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2
Exposure to short-wavelength light, including UV-A and blue light, can degrade high-value products like rosé wine, which are usually packaged in colourless bottles. This study investigates the optimisation of sol¿gel coatings enhanced with UV-absorbing additives (Tinuvin 479 and semaSORB 20109) to provide photoprotection for rosé wines. Coatings with varying additive concentrations (0.5%, 0.75%, 1%, and 1.5%) were applied to glass substrates via spin coating and cured with UV light. Then, optical and mechanical characterisation was performed. The 1.5% concentration semaSORB 20109 bilayer coating demonstrated improved photoprotective properties without compromising colour properties, leading to successful application on glass bottles by spray coating. Accelerated degradation tests confirmed that the optimised coating effectively protected against photodegradation, as indicated by the stability of polyphenol levels and colour parameters in rosé wines. The results suggest that these coatings could be a suitable option for commercial-scale applications, enhancing the light resistance of colourless-bottled products.
Open Access
Exploring the complex interplay of anisotropies in magnetosomes of magnetotactic bacteria
(American Chemical Society, 2025-04-14) Gandía Aguado, David; Marcano, Lourdes; Gandarias, Lucía; Gubieda, Alicia G.; García-Prieto, Ana; Fernández Barquín, Luis; Espeso, José Ignacio; Martín Jefremovas, E.; Orue, Iñaki; Abad Díaz de Cerio, Ana; Fernández-Gubieda, María Luisa; Alonso Masa, Javier; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
Magnetotactic bacteria (MTB) are at the forefront of interest for biophysics applications, especially in cancer treatment. Magnetosomes biomineralized by these bacteria are high-quality magnetic nanoparticles that form chains inside the MTB through a highly reproducible, naturally driven process. In particular, Magnetovibrio blakemorei and Magnetospirillum gryphiswaldense MTB exhibit distinct magnetosome morphologies: truncated hexa-octahedral and cuboctahedral shapes, respectively. Despite having identical compositions (magnetite, Fe3O4) and dimensions within a similar size range, their effective uniaxial anisotropies significantly differ at room temperature, with M. blakemorei exhibiting ∼25 kJ/m3 and M. gryphiswaldense ∼ 11 kJ/m3. This prominent anisotropy variance provides a unique opportunity to explore the role of magnetic anisotropy contributions in the magnetic responses of these magnetite-based nanoparticles. This study systematically investigates these responses by examining static magnetization as a function of temperature (M vs T, 5 mT) and magnetic field (M vs μ0H, up to 1 T). Above the Verwey transition temperature (∼110 K), the effective anisotropy is dominated by the shape anisotropy contribution, notably increasing the coercivity for M. blakemorei by up to twofold compared to M. gryphiswaldense. However, below this temperature, the effective uniaxial anisotropy rapidly increases in a nonmonotonic way, significantly changing the magnetic behavior. Computational simulations using a dynamic Stoner–Wohlfarth model provide insights into these phenomena, enabling careful interpretation of experimental data. According to our simulations, below the Verwey temperature, a uniaxial magnetocrystalline contribution progressively emerges, peaking around 22–24 kJ/m3 at 5 K. Our study reveals the complex evolution of magnetocrystalline contributions, which dominate the magnetic response of magnetosomes below the Verwey temperature. This demonstrates the profound impact of anisotropic properties on the magnetic behaviors and applications of magnetite-based nanoparticles and highlights the exceptional utility of magnetosomes as ideal model systems for studying the complex interplay of anisotropies in magnetite-based nanoparticles.
Open Access
Ni-Mo2C/y-Al2O3 catalysts for syngas production in pyrolysis-dry reforming of plastics - the effect of amine nature on catalyst performance
(Elsevier, 2025-05-29) Pawelczyk, Ewelina; Frackiewicz, Izabela; Gil Bravo, Antonio; Karczewski, Jakub; Maciejewski, Michał E.; Dymerski, Tomasz; Gebicki, Jacek; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
Pyrolysis combined with dry reforming (PCDR) is eco-friendly technology for plastic waste management, allowing for sustainable production of syngas. Design of suitable catalysts with high performance and stability is crucial for its industrialization. In this work, Ni-Mo2C/γ-Al2O3 catalysts were synthesized using organic–inorganic precursors. Three types of amines (hexylamine – aliphatic linear, cyclohexylamine – aliphatic cyclic, aniline – aromatic) were used as carbon source in the precursor preparation to investigate their effect on catalyst physicochemical properties and its catalytic performance. Catalytic performance of the obtained catalysts was examined in PCDR of model waste plastic mixture. It was revealed that catalytic activity of catalysts prepared with aliphatic amines was higher compared to aromatic aniline, amine commonly used for carbide synthesis. The differences in catalyst properties, which affected their catalytic activity were characterized using N2-adsorption at −196 °C, XRD, H2-TPR, SEM, TG/DTG and CO2-adsorption methods. A correlation was observed between amine molecule complexity and Mo2C crystallite size, significantly affecting hydrogen generation. The less complex the amine, the smaller the crystallite and the increased hydrogen production. Moreover, the use of aliphatic amines resulted in the stronger Ni-support interactions, the increased number of more favorable, larger mesopores as well as the presence of the metallic Mo phase and the lack of unbound carbon in contrast to the catalyst obtained using aniline. The catalyst synthesized using hexylamine increased H2 yield by more than tenfold, syngas yield by more than threefold, and the H2/CO ratio by fivefold, which offers an opportunity for future industrialization of PCDR.
Open Access
UV-photoelectron spectroscopy and MS-CASPT2/CASSCF study of the thermolysis of azidoethyl-methyl sulfide: Characterization and mechanism of the formation of S-methyl-N-sulfenylethanimine
(American Institute of Physics (AIP), 2025-05-16) Algarra González, Manuel; Labat, Stephane; Rodríguez-Borges, José Enrique; Pino-González, María Soledad; Sotiropoulos, Jean Marc; Soto, Juan; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
The thermal decomposition of azidoethyl methyl sulfide was studied by real-time UV-photoelectron spectroscopy (UV-PES) at temperatures ranging from 773 to 1023 K. Different ionization energies were obtained using density functional theory calculations to assign UV-PES spectra. The complete active space self-consistent field and multistate second-order perturbation methods were used to predict the formation of different species present in the thermal decomposition process. N2 and S-methyl-N-sulfenylethanimine are generated at 773 K. The first step of the reaction is the dissociation of the molecule into nitrene and nitrogen. The spin state (singlet or triplet) of nitrene formed in the first step of the reaction is temperature-dependent. At low temperatures (T ≤ 650 K), both states are formed with almost the same probability; in contrast, at high temperatures (T ≤ 1000 K), singlet nitrene is the majority intermediate. From this singlet nitrene, three stable reaction products were detected in the experiments: an imine derivative, a four-member cyclic derivative, and a sulfenyl derivative.
Open Access
Transfering sustainability competences through green pedagogies and service-learning in higher education
(European Center of Sustainable Development, 2025-02-01) Cantalejo Díez, María Jesús; Martínez Aldaya, Maite; Navarlaz Fernández, Isabel; Ciencias; Zientziak; Agronomía, Biotecnología y Alimentación; Agronomia, Bioteknologia eta Elikadura
Sustainability competences are reflected in the ability to look ahead to change and shape the future of the societies in which they live through active participation in the sense of sustainable development. Through service-learning, students take responsibility for their actions. The complex nature of sustainability issues makes it useful to explore problems and their solutions holistically. In the framework of the NEMOS project (A New Educational Model for Acquiring Sustainability Competences through Service-Learning), a collaborative process was initiated to pool the knowledge and experience of five Higher Education Institutions working together to implement new educational models for effectively acquiring sustainability competences through service-learning in food-related degrees. This EU-funded project was launched and aimed to advance the transition to sustainability education through practical and innovative educational approaches and interventions. Green pedagogy can support transformative learning through the exploration and clarification of learners
Open Access
Metal-free nanostructured-carbon inks for a sustainable fabrication of zinc/air batteries: from ORR activity to a simple prototype
(Wiley, 2024-08-14) Santos, Florencio; Lorca, Sebastián; González-Martínez, Juan F.; Urbina Yeregui, Antonio; Álvarez-Sánchez, Miguel A. ; González-Domínguez, José M.; García-Bordejé, Enrique; Ansón-Casaos, Alejandro; Benito, Ana M.; Maser, Wolfgang K.; Fernández Romero, Antonio J.; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
Zinc/air batteries are convenient energy storage devices for both small and massive applications. While future perspectives indicate the need for low-cost components and sustainable fabrication processes, the battery performance is in part controlled by the kinetics of the oxygen reduction reaction (ORR), which typically involves transition metals as catalysts. In this context, we prepare a series of metal-free water-based carbon inks, which are tested for their catalytic performance, once deposited on a gas-diffusion substrate, in the air cathode of a simple battery prototype. The inks contain a variety of well-defined carbon nanomaterials and additives, exhibiting different physicochemical properties that critically influence the interaction with the gas diffusion hydrophobic substrate. The intrinsic ORR catalytic activity of the ink material is also analyzed on a glassy carbon electrode by the rotating ring-disc electrode (RRDE) method and specific capacitance measurements. The discharge capacity on our zinc/air battery prototype correlates well with the intrinsic catalytic activity in the RRDE. However, only the activity in the RRDE does not actually assure the performance on the commercial cathode of the prototype, since other chemical compatibility issues play a role. Thus, we highlight the importance of catalyst testing, not only on the RRDE but also under realistic device conditions.
Open Access
Compact wideband groove gap waveguide bandpass filters manufactured with 3D printing and CNC milling techniques
(MDPI, 2023-07-07) Máximo-Gutierrez, Clara; Hinojosa, Juan; Abad, José; Urbina Yeregui, Antonio; Álvarez-Melcon, Alejandro; Institute for Advanced Materials and Mathematics - INAMAT2; Ciencias; Zientziak
This paper presents for the first time a compact wideband bandpass filter in groove gap waveguide (GGW) technology. The structure is obtained by including metallic pins along the central part of the GGW bottom plate according to an n-order Chebyshev stepped impedance synthesis method. The bandpass response is achieved by combining the high-pass characteristic of the GGW and the low-pass behavior of the metallic pins, which act as impedance inverters. This simple structure together with the rigorous design technique allows for a reduction in the manufacturing complexity for the realization of high-performance filters. These capabilities are verified by designing a fifth-order GGW Chebyshev bandpass filter with a bandwidth BW = 3.7 GHz and return loss RL = 20 dB in the frequency range of the WR-75 standard, and by implementing it using computer numerical control (CNC) machining and three-dimensional (3D) printing techniques. Three prototypes have been manufactured: one using a computer numerical control (CNC) milling machine and two others by means of a stereolithography-based 3D printer and a photopolymer resin. One of the two resin-based prototypes has been metallized from a silver vacuum thermal evaporation deposition technique, while for the other a spray coating system has been used. The three prototypes have shown a good agreement between the measured and simulated S-parameters, with insertion losses better than IL = 1.2 dB. Reduced size and high-performance frequency responses with respect to other GGW bandpass filters were obtained. These wideband GGW filter prototypes could have a great potential for future emerging satellite communications systems.
Open Access
Passive heating and cooling of photovoltaic greenhouses including thermochromic materials
(MDPI, 2021-01-15) Padilla, Javier; Toledo, Carlos; López-Vicente, Rodolfo; Montoya, Raquel; Navarro, José-Ramón; Abad, José; Urbina Yeregui, Antonio; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
The integration of photovoltaic technologies into greenhouse envelopes appears to be an innovative and environmentally-friendly way to supply their various energy demands. However, the effect on the inner growing conditions, especially on the temperature, must be assessed in order to effectively implement this solution. In this study, experimental temperature data were obtained over two years for four structures built with different photovoltaic technologies (mono-crystalline silicon, amorphous silicon, cadmium telluride, and an organic polymeric technology) and fitted to a thermal model in order to provide a comprehensive analysis of their potential utilization as a cover material in greenhouses. Additionally, the thermal effect of color in structures composed of several common construction materials (brick, wood, plasterboard and glass) was quantified and modelled, supplementing the thermal analysis of passive solutions for this application. In all cases, inner and ambient temperature differences of up to +20 °C, created by a passive heating effect during the day, and – 5 °C, created by a passive cooling effect during the night, have been observed, suggesting the use of the photovoltaic modules with different degrees of structure coverage, complemented with the color tuning of the modules themselves as passive methods to control the temperature and light spectrum of greenhouses.