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Mg vacancy and impurity-limited MgO single crystal thermal conductivity
No full textData will be made available on request.Magnesium oxide (MgO) exhibits one of the highest thermal conductivities among oxides and is widely used as a dielectric material and substrate in semiconductor devices, in refractory applications, and as a promising filler in thermal interface materials for electronics. Its high thermal conductivity may be sensitive to impurity and defects, yet this influence is still uncertain. Here, the impact of the common impurities, i.e., Al, Ca, Ti, V, Fe, Si, B, Nb, Zr, Na, and K, as well as Mg and O vacancies on phonon scattering and thermal conductivity of MgO is studied using a fully first-principles T-matrix framework. It is found that B, Nb, and Zr impurities, along with Mg vacancies, lead to exceptionally strong reductions in thermal conductivity. By contrast, O vacancies and other impurities have modest to minimal impacts. Leveraging the T-matrix results, we reassess the perturbative, mass-only formalism whose use is pervasive in the literature and show that neglecting bond disorder does not necessarily lead to underestimation: for all transition-metal impurities studied, bond perturbations partially cancel mass disorder, causing the traditional perturbative model to overestimate scattering. We propose a simple modified perturbative expression that incorporates both mass and bond disorder and closely reproduces the T-matrix trends. Our predicted low-temperature trends by including phonon-impurity and phonon-boundary scattering match reasonably well with experiments. This work provides an in-depth study of impurity- and vacancy-limited thermal conductivity of MgO and suggests that reported “high-purity” MgO values have likely not yet reached the intrinsic upper limit, which may be substantially higher.This research was supported in part by the Nano & Material Technology Development Program through the National Research Foundation of Korea (NRF) funded by Ministry of Science and ICT (RS-2024-00444574) and in part by National Science Foundation (NSF) (award number: CBET 2337749). Z.H. acknowledges support from the Center for Thermal Energy Transport under Irradiation (TETI), an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Office of Basic Energy Sciences. J.C. acknowledges grant CEX2023-001286-S funded by MICIU/AEI/10.13039/501100011033 and grant PID2023-148359NB-C21 funded by MICIU/AEI/10.13039/501100011033 and the European Union FEDER. Computation used resources from Bridges-2 at Pittsburgh Supercomputing Center through allocation MCH240097 from the Advanced Cyberinfrastructure Coordination Ecosystem: Services & Support (ACCESS) program and the Center for High Performance Computing at the University of Utah.CEX2023-001286-SPeer reviewe
Selected sustainably synthesized metal–organic frameworks for hydrogen and carbon dioxide storage
No full textThe experimental data that support the findings of this study will be available upon request.Advance Article.Selected metal–organic frameworks (MOFs) including Al–MIL-53–NH2, Fe–MIL-100, Zr–BDC and Zr–BDC–NH2 were synthesized via a sustainable approach and tested for hydrogen and carbon dioxide storage. The synthesis was conducted at room temperature in the presence of water acting as a solvent. Crystalline Fe–MIL-100, nanocrystalline Al–MIL-53–NH2, and semi-crystalline Zr–BDC and Zr–BDC–NH2 were formed as confirmed by powder X-ray diffraction. Fourier transform infrared spectroscopy further confirmed the successful metal–ligand coordination in the MOFs. Thermogravimetric analysis shows that Zr–BDC was the most stable among the synthesized MOFs as it started to decompose above 500 °C. Morphological evaluation using field emission scanning electron microscopy reveals that Fe–MIL-100 consisted of octahedral-shaped crystals while Al–MIL-53–NH2, Zr–BDC and Zr–BDC–NH2 manifested as agglomerated particles. The agglomeration, further validated by transmission electron microscopy, results from the clustering of nanocrystals or small particles. This occurs due to the rapid formation of the precipitate during the room-temperature synthesis, where water serves as the solvent for the specified MOFs. The highest Brunauer–Emmett–Teller (BET) surface area (2013 m2 g−1), determined from nitrogen sorption, was recorded for Fe–MIL-100. Accordingly, Fe–MIL-100 exhibited the highest H2 uptake (1.0 wt% at 77 K and 1 bar) and CO2 storage (8.5 wt% at 298 K and 1 bar). This study illustrates the potential of certain sustainably produced MOFs for gas storage applications. Sustainably prepared MOFs provide the benefit of scalable synthesis suitable for industrial production by reducing reaction times and employing environmentally friendly solvents.We thank the Department of Science, Technology and Innovation (DSTI) and the National Research Foundation (NRF) South African Research Chairs Initiative (SARChI) (Grant Number: 2090155358). The NRF CPRR funding stream (Grant Number: 0215586378) is also acknowledged. NRH acknowledges the University of Pretoria for post-doctoral researcher funding. ID acknowledges funding from the MCIN/AEI under grant code: PID2022-136321OB-C21/AEI/10.13039/501100011033/FEDER, UE. This research work was also financially supported by Haramaya University (HURG-2020-03-02-75), Ethiopia.Peer reviewe
Influence of external carbon sources on the morpho-structural and mechanical properties of 3D-structured carbon monoliths
No full textHigh purity carbon structured devices have been prepared by resorcinol-formaldehyde polycondensation in aqueous medium and alkaline conditions with starch as a binder and various external carbon sources. Polylactic acid (PLA) templates have been used to perform the structures which, after controlled and fixed pyrolysis conditions, generate 3D carbon devices with tuneable geometry and properties, as well as mechanical integrity. This study investigates the influence of the nature of the added carbon (activated charcoal, powdered graphite, multi-walled carbon nanotubes, cellulose-derived biocarbon, and synthetic carbon xerogel) on the morpho-structural and mechanical properties of the resulting monoliths. The nature and proportion of the added carbon significantly affect crystallinity, porosity, surface area, and compressive strength. The addition of either carbon xerogel or carbon obtained by pyrolysis of cellulose allows obtaining structures with channels with suitable mechanical properties with no volume reduction or structural collapse. The best mechanical properties are obtained using carbon xerogel as additive, as it allows using a higher C/OS weight ratio (1.61), giving an apparent density of 0.79 g/cm3 and compressive strength (σ) of 5.4 MPa. The use of sustainable cellulose-derived carbon as additive results in a monolith with lower mechanical properties (apparent density = 0.46 g/cm3, σ = 1.4 MPa), probably due to the lower C/OS ratio (0.42) but higher mesoporosity (42 vs. 17 %), emerging as the most promising candidate for structured catalytic support applications. The methodology enables the fabrication of high-purity carbon structures with customizable properties suitable for advanced catalytic processes.Financial support was obtained from Spanish Ministerio de Ciencia e Innovación (MCIN/AEI /10.13039/501100011033/) and for FEDER Funds (Una manera de hacer Europa), Project PID2020-113809RB-C32.Peer reviewe
Integrating conservation priorities into spatial planning for renewable energy development: The case of the Spanish imperial eagle
No full textThe data that has been used is confidential.The rapid expansion of renewable energy infrastructure across the Iberian Peninsula presents new challenges for the conservation of endangered species, such as the Spanish imperial eagle (Aquila adalberti). We assessed the spatial overlap between operational wind and photovoltaic energy facilities and the key ecological areas used by juvenile Spanish imperial eagles and areas occupied by resident breeding adults. We analysed GPS-tracking data from 61 juveniles monitored between 2017 and 2023, together with breeding data from official records, to estimate dispersal and breeding ranges. We found that 40 % of the juvenile dispersal area suffers moderate to high-risk from energy installations, and that these areas host over 46 % of all wind turbines and 67 % of the photovoltaic energy surface in the study area. Of the eagles monitored, 36 % died during the study period, with 59 % of the human-activity related deaths linked to energy infrastructure, primarily due to electrocution. We also evaluated the current and zones excluded from the designation of go-to areas for renewable energy implementation under Directive (EU) 2023/2413 and found that only 21.3 % of the juvenile dispersal area and 38 % of the breeding range are currently protected. Proposed extensions to exclusion zones would significantly increase the protected area (18–26 %) but still leave ecologically sensitive areas at risk. These results underscore the urgent need to integrate fine-scale ecological data into renewable energy planning to reduce conflicts with endangered species conservation.This work was carried out by Fundación CBD-Habitat and funded by the Spanish Ministry for the Ecological Transition and the Demographic Challenge (MITECO). The content of this publication does not necessarily reflect the views of MITECO. Jorge Tobajas was supported by a postdoctoral contract (Junior +) from the University of Castilla-La Mancha (UCLM) partially funded by the European Union through the European Social Fund Plus (FSE+), and a postdoctoral contract funded by the University of Cordoba through the “Plan Propio de Investigación Enrique Aguilar Benítez de Lugo 2024”. The authors would like to express their sincere gratitude to J. Caldera, J. Lara Ismael Pérez and David Mingot from the Autonomous Community of Madrid, D. Cubero, V. Salvador, E. Madejón, N. Zabala, Elena Hernández and C. Pérez from the Junta de Castilla y León. We are also grateful to F. J. Sánchez Mateos, F. Guil, J. García, L.M. González, C. Carrapato, N. El Kadir, E. Sotolargo, D. García, L. Benavente, M. Reina, T. Pereyra, L. Bolonio, C. Palacín and L. Sebastián. V. García and A. Díaz from the MITECO for their invaluable support and assistance throughout this project. M. Dagys for his invaluable assistance and willingness to help us with GPS devices. We thank to Phil Whitfield and an anonymous reviewer for their useful suggestions, which helped us to improve our manuscript.Open Access funding provided by Universidad de Castilla-La Mancha.Peer reviewe
Convergence of Digital Twins and food drying technology: How to bring the next generation of dryers to life!?
No full text23 pages, 5 tables, 1 figureDigital Twins technology is rapidly growing and has the potential to revolutionize traditional food-processing methods. However, their application in food-drying processes is still in its infancy. This study aimed to explore how Digital Twins can be applied to food drying process. Traditionally, food drying is performed under constant conditions, where air temperature and velocity remain constant. However, the literature review shows that variable drying conditions (trajectories) can improve both energy efficiency and product quality. The challenge is that the trajectories are calculated based on what happened in the process, not what is currently happening. Digital Twins address this shortcoming by enabling decision making based on real-time data. In this conceptual review paper, physiochemical parameters as an element of the physical world of a Digital Twins-based smart food dryer is first presented. Next, potential sensors for building a digital counterpart of the physiochemical parameters are discussed. This is followed by mathematical models, dynamic optimization, and advanced control, which are the core elements of a decision-making and control unit. Finally, future research needs are discussed. This conceptual review paper will guide and give a solid insight to academic researchers, companies, and other potential stakeholders on merging Digital Twins and food drying technologiesWe would like to thank Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB) for the financial support of this studyPeer reviewe
Impact of air purifiers on occupational particle exposure in an enclosed bus workshop
No full textWorkers in bus workshops are exposed to elevated concentrations of fine (PM2.5, 2.5, PM4, PM10) were monitored at near field, breathing zones, and far field locations during maintenance tasks. The first campaign established baseline conditions, while the second assessed the impact of four air purifiers (APs). Baseline monitoring showed exposure peaks during high-emission activities such as brake servicing, and cold engine starts, with PNCs reaching 4.5 × 105 cm-3 and PM4 up to 549 µg m-3. While gravimetric concentrations remained below mass-based occupational exposure limits, UFPs and EC exceeded precautionary health benchmarks. The use of APs increased the effective air exchange rate and reduced PNCs (2.5, PM4, and PM10 by 45%, 49%, and 53%, respectively. EC decreased by 46%, whereas BC and OC showed negligible changes. Size-resolved analysis confirmed highest removal efficiency for coarse particles (60% at 10 µm) and lowest (33%) within 300-700 nm range, the most penetrating particle size. This study demonstrates that bus workshops present clear risks of occupational particle exposure, and that APs can significantly reduce concentrations, though limitations remain for UFPs and semi-volatile organics.We wish to thank the participating company and workers for their contributions to this research and welcoming us on the worksite.
Funding statement: This research was financially supported by AeroSolfd, a project funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Climate, Infrastructure and Environment Executive Agency (CINEA). Neither the European Union nor the granting authority can be held responsible for them. AeroSolfd is a Horizon Europe project supported by the European Commission under grant agreement No. 101056661.
Swiss participant(s) in the AeroSolfd project are co-funded by the Swiss State Secretariat for Education, Research and Innovation (SERI).Peer reviewe
Look at those nasty and lovely birds! Assessing preferences and emotional responses of visitors to a National Park
No full text11 pages, 4 tables, 2 figuresPublic perceptions of wildlife are shaped not only by ecological knowledge but also by emotional responses, social values and representations, lived experiences, and specific geographical and socio-cultural contexts. This study explores how visitors to the Atlantic Islands of Galicia National Park (PNIAG), a protected area of high ecological value in north western Spain, perceive, express preferences for, and emotionally respond to eight bird species with varying ecological roles and levels of human interaction. Using a structured survey administered to 450 visitors, we assessed species recognition, perceived “naturalness” and “goodness”, as well as emotional associations and preferences toward each species. The results reveal that some conservation-priority species, such as the yellow-legged gull (Larus michahellis) and the European shag (Gulosus aristotelis), which have experienced marked population declines, are often misunderstood or under-recognized by the public. In contrast, more familiar urban birds like the house sparrow (Passer domesticus) and the common blackbird (Turdus merula) evoked strong positive emotions and are consistently preferred. The European shag is the flagship species of the PNIAG, and has also been the subject of significant positive emotions, having been selected by visitors as their preferred species. Emotional responses emerged as significant predictors of preference: positive emotions such as joy and awe increased the likelihood of a species being favored, while negative emotions like fear, disgust, or anger were associated with rejection. These findings underscore the need to integrate emotional and cognitive dimensions into conservation communication and public engagement strategies, particularly to address potential mismatches between conservation priorities and public perceptions. Understanding how emotions shape attitudes toward wildlife can help decision-makers design more inclusive, effective conservation interventions that align ecological priorities with public values, and foster deeper human–nature connectionsEG would like to acknowledge the funding support provided by the Ministry of Science, Innovation and Universities, through the Juan de la Cierva Fellowship (JDC2022-048423-I). MS would like to thank the Ministry of Science, Innovation and Universities for the support received to carry out a research fellowship at the Department of Environment and Geography of the University of York, UK (ref. PRX23/00008)Peer reviewe
Xylem Pit Anatomy and Minimum Leaf Conductance Drive Drought Mortality in Pinus pinaster
No full text16 páginas.- 6 figuras.- 4 tablas.- referenciasDrought-triggered forest die-off events are commonly attributed to hydraulic failure, carbon starvation, or a combination of the two. Nevertheless, the anatomical and physiological traits that make trees vulnerable to drought in the field are often unknown, hindering predictive efforts. To identify these traits, we compared coexisting declining (D, heavily defoliated) and non-declining (ND, lightly defoliated) trees. We studied a recent die-off event affecting maritime pine (Pinus pinaster) in north-eastern Spain that started after the severe 2017 drought. We compared the depth of soil water uptake, estimated using δ18O and δ2H in soil and xylem water samples, as well as field measurements. We also measured anatomical and physiological wood and leaf variables, paying particular attention to pit anatomy and minimum leaf conductance (gmin). The D trees were smaller in terms of diameter and height, and exhibited lower growth rates. They also formed tracheids with smaller lumen diameters and thinner cell walls than the ND trees. The measured soil depth was greater for ND than for D trees. Isotope data also indicated that ND trees used water from deeper soil layers than D trees during the late summer period of peak drought severity. No differences in the sapwood concentrations of non-structural carbohydrates were found between the two tree types. The D trees had lower midday water potentials than ND trees, and the pressure inducing 50% loss of hydraulic conductance (P50) and gmin were higher in D trees. The D trees also exhibited lower torus overlap, margo flexibility and valve effect than ND trees. However, these differences in pit anatomy were observed in the 2010s when ND trees exhibited higher δ13C-derived intrinsic water-use efficiency. A combination of traits, such as a large pit aperture and a high gmin makes trees vulnerable to drought stress.This study was funded by projects PID2021‐123675OB‐C43 andTED2021‐129770B‐C21 (Spanish Ministry of Science and Innovation [Ministerio de Ciencia, Innovación y Universidades]). We sincerelythank Francisco José García Breijo (Univ. Politécnica de Valencia,Spain) for his help with wood anatomy analyses and Aragón Govt. forsampling permissions and facilitiesPeer reviewe
Infection characteristics of Anisakis simplex (s.s.) in squids from NE Atlantic waters
No full text10 pages, 4 figuresCephalopods have increasingly been reported as hosts of zoonotic parasites, notably Anisakis simplex (sensu stricto) (Nematoda: Anisakidae), which poses risks to human health through raw or undercooked seafood consumption. This study investigates the infection characteristics and anatomical distribution of A. simplex (s.s.) larvae in four commercially important squid species (Loligo forbesii, Illex coindetii, Todarodes sagittatus and Todaropsis eblanae) collected from Northeast Atlantic waters. A total of 425 specimens were examined for anisakid nematodes using the UV-press detection method (ISO 23036-1: 2021), and the larvae were identified morphologically and genetically by mtDNA cox2 gene sequencing. Anisakis simplex (s.s.) was detected in all species, with T. sagittatus showing the highest prevalence (69.0 %). Overall, larvae were predominantly found in the stomach and gonads, but notably also in the mantle tissue, particularly its posterior region adjacent to the digestive tract. The parasite was absent from the arms, tentacles and fins. A statistically significant positive correlation was observed between mantle length and Anisakis presence across all species. These findings confirm that squid, especially mesopelagic and demersal species, serve as important paratenic hosts of A. simplex (s.s.) in Northeast Atlantic waters, and highlight potential food safety risks associated with their consumption. The presence of larvae in mantle tissues emphasizes the need for enhanced surveillance, processing standards, and public awareness to mitigate zoonotic and allergenic risksJorge Hernández-Urcera carried out this work through a research stay at the Institute of Marine Research (Bergen, Norway), made possible by a mobility grant from the Spanish Ministry of Universities (reference CAS22/00221)Peer reviewe
Impact of organic amendments on carbon stability and carbon use efficiency in acidic and alkaline soils
No full text14 páginas.- 5 figuras.- 4 tablas.- referencias.- The electronic annex includes: A detailed description of the Cmicro calculation, an image of the automatic respirometer along with a diagram of its operation (SF1), standard curves for qPCR-based quantification (SF2), FT-IR spectra (SF3), thermal analysis profile of soils (SF4), and ST1 containing all the results of thermogravimetric analyses. Supplementary data to this article can be found online at https://doi.org/10.1016/j.apsoil.2025.106577Soils represent the largest reservoir of organic carbon in terrestrial ecosystems, yet the mechanisms controlling its stabilization and turnover are still not fully understood, limiting our ability to anticipate their response to climate change. Microbial processes are central to the formation, preservation, and loss of soil organic carbon (SOC), with microbial carbon use efficiency (CUE)—the fraction of assimilated carbon allocated to growth versus respiration—emerging as a key integrative parameter of microbial functioning. While CUE has been proposed as a predictor of SOC persistence, its contribution remains debated. In parallel, CUE is gaining attention in the context of carbon farming policies, as it links microbial functioning with soil carbon sequestration. Among the management practices aimed at enhancing SOC, organic amendments such as compost and biochar stand out for their capacity to influence CUE and improve soil functioning. In this study, we assessed how different organic amendments affect SOC stability and sequestration in two contrasting soils from the Iberian Peninsula: acidic grasslands and alkaline rain-fed soils. The amendments included four biochars, two cattle digestates, a green compost, and a biochar–compost mixture. Over 100 days, soil respiration (CO₂ emissions), microbial biomass, and soil properties were monitored using an automatic respirometer. Microbial CUE and microbial activity largely determined carbon (C) retention in the studied soils. Cow digestate increased microbial activity but reduced microbial CUE in both soils, leading to higher C losses through respiration and lower C retention. In contrast, biochars—particularly those produced from white poplar wood, olive pomace and rice husk—enhanced carbon recalcitrance, extending the residence time of the stable C pool by six to nine times compared with unamended soils. Microbial analyses showed that bacterial loads were 2–3 orders of magnitude higher than fungal loads. Compared with acidic grassland soils, alkaline soils generally showed higher microbial CUE values, reflecting a greater potential for C sequestration. These findings also indicate that microbial CUE exhibited clear soil-specific behavior, being consistently higher in the AS than in the acidic GS. This pattern suggests that differences in microbial community dominance—particularly the relative contribution of bacteria and fungi—may underlie the contrasting CUE responses observed between soils, a topic that warrants further investigation in future studies. In the alkaline soils, digestate amendments resulted in the highest bacterial abundance, whereas rice husk biochar favored fungal growth. Additionally, the high Cu and Zn content of cow manure digestate posed risks in acidic soils. This study also emphasizes that amendment strategies should be tailored to soil type to optimize carbon sequestration. Moreover, a novel thermal–respirometry correlation model was also developed, providing a practical tool for assessing soil carbon dynamics and C stability.The European Joint programme EJP SOIL from the EU Horizon 2020 R&I programme is thanked for funding the subprojects EOM4SOIL, MaxRoot-C & MixRoot-C (Grant agreement N° 862695). The Spanish Ministry of Science and Innovation (MCIN) and AEI are thanked for funding the projects RES2SOIL (PID2021-126349OB-C22) and AGRORES (PID2021-126349OB-C21) (MCIN/AEI/ 10.13039/501100011033) P. Campos and Á. Sánchez Martín thank the MICIN (MICIU/AEI/10.13039/501100011033) and FSE+ for funding the contracts PTA2023–023661-I and PTA2021–020000-I, respectively. J. Márquez-Moreno acknowledges the EU, the Spanish government, and the Andalusian Regional Government for funding his contract (no. 01–2022-39492) within the framework of the Recovery, Transformation, and Resilience Plan for Andalusia, NextGenerationEU/PRTR References.Peer reviewe