Global Challenges最新文献

Lead-containing halide perovskites show promise for solar energy but pose ecological and health risks. To address these, researchers are exploring inorganic binary metal perovskites. This study proposes an eco-friendly, durable hole transport layer (HTL)-free design of CsSn_0.5Ge_0.5I₃ with high power conversion efficiency (PCE). Using the SCAPS-1D simulator, we assessed the efficiency of an HTL-free planar heterojunction, while the Density Functional Theory (DFT)-based CASTEP simulator evaluated the optical properties of CsSn_0.5Ge_0.5I₃ in an orthorhombic structure. Key findings highlight enhanced performance under 100 Wm⁻² AM 1.5G illumination by optimizing absorber layer thickness to 800 nm and reducing defect densities in both the perovskite absorber layer and interfaces to 1 × 10¹⁴ cm⁻³.Additonally, the effects of different electron transport materials (ETMs), optimization of electron transport layer (ETL) thickness (30-50 nm), and back contact design improvements were examined. The simulation's results included an increase over the highest values reported in the literature: an open circuit voltage (Voc) of 1.06 V, a short circuit current density (Jsc) of 28.52 mA/cm², a fill factor (FF) of 86.57%, and a PCE of 26.18% for the FTO/Zn_0.875Mg_0.125O/CsSn_0.5Ge_0.5I₃/Se perovskite solar cell (PSC). This research provides theoretical insights for developing high-efficiency power modules without HTLs with significant industrial and research potential.

Highly sensitive vertically aligned carbon nanotube arrays (VANTAs) interdigitated electrode (IDE) arrays are developed for electrochemical biosensing of two cytokines (i.e., interleukin-10 (IL-10) and interferon-gamma (IFN-γ)) that are useful for early detection Johne's disease (Bovine Paratuberculosis) in cattle. The high aspect ratio VANTA-IDEs (50–60 µm in height) are grown through a chemical vapor deposition process from an iron (Fe) catalyst that is lithographically patterned on a silicon wafer with equal finger width and inter-finger spacing of 25 µm. After functionalization with distinct antibodies the VANTA-IDEs are capable of selective detection of both IL-10 and IFN-γ within an actual biological matrix (i.e., diluted bovine implant supernatant) over concentration ranges of 0.1 to 30 pg mL⁻¹ (limit of detection – LOD: 0.0911 pg mL⁻¹) and 50–500 pg mL⁻¹ (LOD: 24.17 pg mL⁻¹), respectively with a response time of <35 min. Results demonstrate important initial steps for rapid, pen-side identification of cattle with stage-I Mycobacterium avium subspecies paratuberculosis infection before physical symptoms of Johne's disease are present. Such a rapid pen-side diagnostic test can be used on cattle at an auction or before they are introduced to a herd to ensure the larger population does not become infected with Johne's disease.

This paper assesses the National Recovery and Resilience Plans (NRRPs) of EU member states and regions to uncover commonalities and differences between green and digital transitions, focusing on the role of institutions, among additional socio-economic drivers, in modeling them. To that end, relevant indicators have been assembled, and several econometric models have been developed and tested to evaluate institutional performance in relation to green and digital transformations. The study reveals discrepancies in the two explored transition fields and highlights the power of institutional factors in boosting them. Specifically, the findings demonstrate that the green transition in EU regions is positively associated with variables such as life expectancy, institutional quality, tertiary education attainment, and small and medium enterprises (SMEs) with innovative activities, while the fruits of digitalization are mainly allied to population with higher studies, core creative class employment, accountability of institutions, and innovative SMEs. These insights offer valuable guidance for decision-makers to draw lessons from high-performing or successful regions and strategically assign resources. This includes paying attention to regional financial allocations and their alignment with territorial planning and long-term policies.

The cover image is based on the Article Photoelectrocatalytic Hydrogen Generation: Current Advances in Materials and Operando Characterization by Mohammed Ahmed Zabara et al., https://doi.org/10.1002/gch2.202400011

The scale of food waste across Europe is alarming, and its reduction is becoming an important public policy and governance issue. Sustainable Development Goal Target 12.3 constitutes a global attempt to galvanize system-level reductions. In response, layers of varied regulation and governance at regional and national levels have emerged. This paper studies the types of governance architectures visible across Europe, what policy interventions they bring, and whether responses to the food waste challenge are converging. It looks at four leading food waste jurisdictions—France, England, Norway, and Italy—and investigates the hidden realities obscured by the simplistic division of legislative/top-down versus voluntary/bottom-up approaches. It applies a governance matrix to understand the variety of food waste “steering modes”, exploring both the extent to which a regime is hierarchical and/or non-hierarchical and why. Notably, the paper also identifies some general tendencies in food waste governance, including legislative threats, challenges in distributing responsibility across the actors, focus on “low hanging fruits”, and an overall harmonization of policy responses in a neoliberal paradigm, with redistribution often pursued as a panacea for the food waste crisis.

This research explores green-technology alternatives to extract vegetable oils as alternatives to hexane, a non-renewable solvent, focussing on sunflower oil. It compares pressurized liquid extraction (PLE) with ethanol and supercritical fluid extraction (SFE) with CO₂. Both processes aim to maximize oil yield, tocopherol content (α, β, γ, and δ), fatty acid profile (FA), and triacylglycerol (TAG) composition. Results show that SFE at 32 MPa achieves an 87.58% oil recovery, while PLE at 84 °C achieves 93.93%. PLE with ethanol extracts polar minority compounds along with the oil due to its higher temperature, favoring extraction. The total tocopherol content is 91.17 mg/100 g of oil in optimized SFE conditions, with α-tocopherol extraction influenced by temperature, γ and δ-tocopherol by pressure. PLE yields 83.16 mg/100 g of oil in tocopherols influenced less by process variables. The fatty acid (FA) profile do not vary in the oils obtained from different processes or based on the variables within each process, with linoleic and oleic acids being the most abundant. Similarly, triacylglycerols (TAGs) C54:5 and C54:6 are predominant. The optimization of SFE and PLE processes indicates a strong potential for using green solvents in the extraction of tocopherol-rich sunflower oil.

The study aims to investigate the impact of various drying techniques on the quality of sulfated polysaccharides (SP) extracted from Skipjack tuna (Katsuwonus pelamis) skin. Three drying methods, namely microwave drying (M-KPP), freeze-drying (F-KPP), and hot air drying (HA-KPP), are examined. The chemical and monosaccharide compositions of SP are significantly affected by the drying methods. The extraction yields for M-KPP, F-KPP, and HA-KPP are 3.30%, 3.11%, and 2.50%, respectively (P < 0.05). Additionally, HA-KPP, with 10.67% moisture content, exhibits the lowest moisture level among the dried samples (P < 0.05). Furthermore, the structural properties of SP remain consistent across different drying methods, as indicated by FTIR, XRD, and DSC analyses. F-KPP demonstrates the highest antioxidant properties. The functional and antimicrobial activities of SP are significantly influenced by the drying technique, with hot air drying resulting in increased foaming capacity and microwave drying showing enhanced antimicrobial activity. In conclusion, the findings demonstrate that the functionality and bioactivity of SP from tuna skin are greatly influenced by the drying technique employed, suggesting that the selection of the optimal method should be tailored to the desired properties of the SPs and given careful consideration.

In this study, the impact of zinc oxide nanoparticles (ZnO-NPs) generated using rosemary extract, synthesized using environmentally friendly processes and integrated into a cross-linked polymer matrix, on growth performance of wheat is evaluated. Rosemary extract used as coating, stabilizing, and reducing agents in this green synthesis method. Fourier transform infrared spectroscopy analyses demonstrated the presence of phytochemical constituents of the plant extract that served as capping agents during the synthesis process. The nanoparticles are sprayed to the plant leaves. The effects of nanoparticles within the hydrogel on plant development are compared with the effects of nanoparticles in suspension. The percentage of seed germination is unaffected by either rosemary- or raw-ZnO-NPs; however, the root and shoot elongation are considerably impacted by the nanoparticle treatments. The threshold concentrations are determined as 3000 mg L⁻¹ for rosemary-ZnO-NPs and 2000 mg L⁻¹ for raw-ZnO-NPs. Additionally, antibacterial test results showed that the activity level on Escherichia coli is higher for rosemary-ZnO-NPs compared to raw-ZnO-NPs. The results of this research may provide guidance on how green synthesis methods and the use of nanoparticle-hydrogel composites in plant breeding can be used in future agricultural applications. This can be considered an important step in terms of agricultural innovations and sustainability.

Magnetically separable Fe₃O₄, Fe₃O₄@SiO₂, Fe₃O₄@SiO₂@ZnO, and Fe₃O₄@SiO₂@ZnO–Ag composites are synthesized using hydrothermal and wet chemistry methods. The samples obtained are characterized in terms of morphology, composition, optical, and magnetic properties using TEM, SEM-EDS, XRD, FTIR, VSM, XPS, and UV–vis, and the photodegradation of Acid Blue 161 dye under UV irradiation is investigated. As a result of SEM and TEM analyses, the diameters of Fe₃O₄, Fe₃O₄@SiO₂, Fe₃O₄@SiO₂@ZnO, and Fe₃O₄@SiO₂@ZnO–Ag composites are determined as 210, 220, 230 and 235 nm, respectively. The magnetic properties of the samples are determined by VSM analysis. In VSM analyses, magnetization saturation values of Fe₃O₄, Fe₃O₄@SiO₂, Fe₃O₄@SiO₂@ZnO, and Fe₃O₄@SiO₂@ZnO–Ag composites are determined as 81, 64, 41 and 20 emus × ^g−1, respectively. In XRD analysis, the face-centered cubic structure of Fe₃O₄ particles and the hexagonal wurtzite structure of ZnO are determined and it is determined that they are compatible with standard diffraction cards. According to UV–Vis analysis, E_g values for Fe₃O₄, Fe₃O₄@SiO₂, Fe₃O₄@SiO₂@ZnO, and Fe₃O₄@SiO₂@ZnO–Ag composites are found as 1.3, 1.68, 2.21, and 2.15 eV, respectively. Among the photocatalysts prepared, Fe₃O₄@SiO₂@ZnO–Ag composite Acid Blue 161 shows superior removal and recyclability against photodegradation of the dyestuff.