Manganese-copper (Mn-Cu) mixed oxides are promising catalysts for abatement of incomplete combustion products from domestic wood burning, notably CO and Volatile Organic Compounds (VOCs). In this paper, the influence of the Mn/Cu molar ratio on structure, redox properties, and catalytic performances was investigated. Mixed oxides were synthesized by oxalate co-precipitation and calcined under air at 500 degrees C. Physicochemical characterization (XRD, Raman, N-2-physisorption, XPS, H-2-TPR) revealed strong Mn & horbar;Cu interaction. Catalytic tests for total oxidation of CO, toluene, and their mixture showed that copper-rich oxides, especially Cu1Mn0.25Ox, achieved the best performance at low temperature (T-50 = 49 degrees C and 230 degrees C for the oxidation of CO and toluene respectively). In alternating feeding, the presence of CO promotes the oxidation of toluene at low temperature, while an excess of Cu in the material ensures full CO2 selectivity. For mixed oxides, the linear correlation between Cu2+ -> Cu+ reducibility and T-50 for toluene oxidation in presence of CO demonstrates that the incorporation of Mn into Cu oxides enhances oxidation. Overall, tuning the Mn/Cu ratio enables efficient, selective, and simultaneous removal of CO and VOCs, providing a cost-effective solution for emission control from biomass combustion.
Introduction Afforestation is increasingly recognized as a key strategy to address climate change and ecological degradation, offering multiple ecosystem services. However, strategic planning is needed to ensure that afforestation actions are ecologically effective and economically efficient by targeting areas where ecosystem service provision is most significant.Objectives In this study, we provide a workflow to prioritize afforestation areas at national scale tailored to four distinct ecosystem service goals: ecological connectivity, human health, climate mitigation, and water regulation.Methods Using Italy as a case study, we applied goal-specific analysis to areas considered suitable for afforestation, integrating geospatial datasets of environmental and social factors. For each objective, spatial indicators were combined into a priority map at 1 km resolution, subsequently aggregated into composite maps. The top 20% priority areas for each objective were identified to inform national and regional planning.Results High-priority areas to improve ecological connectivity were focused around urban centers and extensive agricultural plains. Water regulation benefits were most relevant in urbanized and vineyard landscapes, while urban areas also emerged as priorities for human health. Climate mitigation potential was highest in moist temperate and mountain regions. Overlap among goals was limited, revealing significant trade-offs across ecosystem services.Conclusions The workflow provides a replicable approach to identify goal-specific afforestation priorities across diverse landscapes. It supports coordinated strategies to enhance ecosystem service provision and restoration effectiveness at national and regional levels.
Ensemble inequivalence, where a system's thermodynamic properties depend on the statistical ensemble used to describe it, is a well-established phenomenon in classical systems with long-range interactions. Here, we present a detailed analysis of a quantum ferromagnet spin model that exhibits this same behavior. We find that the microcanonical and canonical phase diagrams are identical at zero temperature (T = 0), but differ significantly at finite temperatures. Our results highlight a breakdown of ensemble equivalence in this quantum long-range model, contrasting with what is observed for short range. These findings have important implications for the study and manipulation of long-range interacting quantum platforms, such as those used in atomic, molecular, and optical physics.
The large van der Waals gap in transition metal dichalcogenides (TMDs) offers an avenue to tune the ground state of 2D materials through the intercalation of magnetic atoms. Here, we investigate the charge correlations in Fe1/3TaS2, Co1/3TaS2, and Fe0.35NbS2 by combining angle-resolved photoemission spectroscopy (ARPES), x-ray scattering, magnetometry, and density functional theory (DFT). We find that, while short-range charge fluctuations develop in Ta-based compounds, Fe0.35NbS2 exhibits long-range charge order which is strongly coupled with magnetic order and tunable by external magnetic field. Our electronic structure analysis reveals that intercalation reconstructs the Fermi surface via charge transfer and band renormalization, yet does not generate the nesting conditions compatible with the observed ordering vectors. Complementary phonon calculations further exclude a conventional electron-phonon origin of charge order. Together, these results establish magnetoelastic coupling as the dominant mechanism behind charge ordering in Fe0.35NbS2 and highlight the contrasting role of Nb and Ta hosts in stabilizing correlated ground states in intercalated TMDs.
Resolving chemical species at the submicrometer scale is crucial in Heritage Science, where synchrotron radiation (SR)-based X-ray methods, including µ-XRF mapping and µ-XANES spectroscopy, offer unique insights into the composition of heterogeneous and opaque materials, such as degraded inorganic pigments in paintings. However, the high intensity and brightness of SR beams pose significant risks of radiation damage, which can compromise both sample integrity and data interpretation. This challenge is notably evident in Prussian blue (a ferric hexacyanoferrate pigment), where X-ray induced photoreduction of Fe3+ to Fe2+ interferes with speciation analysis in faded artworks, necessitating rigorous experimental strategies to ensure data reliability. To address this, we present a multi-scale and multi-technique approach aimed at safely investigating the light-induced degradation of Prussian blue in oil paintings via SR-based X-ray micro-spectroscopic techniques. The study focuses on the 1802 painting Pamphilus and his Servant Davus by the Danish artist Nicolai Abildgaard (Copenhagen, 1743-Frederiksdal, 1809), which exhibits various degrees of fading in the Prussian blue-based paints, particularly evident when comparing light-exposed areas to those protected by the frame. After evaluating the paint composition and fading at the macro-scale using a set of non-invasive MOLAB techniques (namely colorimetry, reflectance UV–VIS–NIR and external reflection mode FT-IR spectroscopies), two micro-samples from light-exposed and unexposed areas were selected for SR-based µ-XRF mapping and µ-XANES spectroscopy at the Fe K-edge. In parallel, a series of Prussian blue-based oil paint mock-ups were prepared, photoaged, and analyzed in advance of historical samples to establish optimal conditions for mitigating SR X-ray induced Fe3+→Fe2+ reduction during measurements, achieved by systematically varying fluence, dose, and temperature. Under these optimized, non-damaging conditions, we successfully mapped the stratigraphic distribution of iron compounds at submicrometric resolution in the historical cross-sections. The results, unaffected by analytical artifacts, revealed the nature of the secondary products responsible for the observed fading in Abildgaard’s painting. Consequently, this research offers a validated experimental approach for future SR-based X-ray micro-spectroscopy studies of Prussian blue degradation in other artworks.
