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Hybrid Nanofiber-Based Atmospheric Water Harvesters: Sunlight-Driven Operation in Low-Humidity and Low-Illumination Environments
No full textPublisher Copyright: © 2025 American Chemical Society.Aerogels incorporating hygroscopic salts have been widely explored for atmospheric water harvesting (AWH). However, the scalability of these sorbents remains limited due to their reliance on energy-intensive and time-consuming drying methods such as lyophilization or supercritical drying. Here, we present a simple and scalable approach to drying hydrogels with desirable AWH properties using a freezing process followed by solvent exchange and thawing at room temperature. Our system consists of cellulose and silica nanofibers, forming hybrid xerogels with ultralow density (10.86 ± 0.32 mg cm-3), high specific surface area (104.22 m2 g-1), excellent water stability, and mechanical strength. By incorporating carbon-based photothermal materials and lithium chloride as a hygroscopic salt, the xerogels achieve exceptional water uptake capacities ranging from 0.90 to 3.21 g g-1 across a relative humidity (RH) range from 15 to 75%. Under natural sunlight, the AWH xerogel produces water at a rate of 1.17 g g-1 day-1. These results highlight a sustainable and scalable AWH strategy, leveraging ambient-dried xerogels as an energy-efficient solution to mitigate water scarcity.Peer reviewe
Comparison of the iron-bearing crystals and phases from Tamdakht H5 and Annama H5 ordinary chondrites by X-ray diffraction, magnetization measurements and Mössbauer spectroscopy
No full textPublisher Copyright: © 2025 The Meteoritical Society.The iron-bearing phases and crystals within (i) the bulk interior and the fusion crust from Tamdakht H5 and (ii) the bulk interior from Annama H5 ordinary chondrites were studied by optical microscopy, scanning electron microscopy with energy dispersive spectroscopy, X-ray diffraction (XRD), magnetization measurements, and Mössbauer spectroscopy. The main iron-bearing phases/crystals such as olivine, orthopyroxene, clinopyroxene, troilite, chromite, and hercynite, as well as Fe-Ni-Co alloy with the α2-Fe(Ni, Co), α-Fe(Ni, Co) and γ-Fe(Ni, Co) phases were identified in both meteorites. XRD and Mössbauer spectroscopy showed high contents of Fe-Ni-Co alloy in the bulk interiors from Tamdakht H5 and Annama H5 ordinary chondrites. The fusion crust from Tamdakht H5 contains a new phase of magnesioferrite. A classification scheme for H, L, and LL ordinary chondrites using the relative areas of Mössbauer spectral components was applied to these meteorites' classification. The ratios of the M1 and M2 site occupations by Fe2+ in olivine and orthopyroxene were determined using XRD and Mössbauer spectroscopy, showing consistent results. The equilibrium cation distribution temperatures for olivine and orthopyroxene in Tamdakht H5 and Annama H5 were determined using XRD and Mössbauer spectroscopy.Peer reviewe
LSPR-assisted W18O49/ZnO S-scheme heterojunction for efficient photocatalytic CO2 N-formylation of aniline
No full textPublisher Copyright: © 2024 Dalian Institute of Chemical Physics, the Chinese Academy of SciencesDesigning highly efficient photocatalyst for the valorization of CO2 is an ideal strategy to reduce greenhouse gas emissions and utilize solar energy. In this study, a S-scheme heterojunction photocatalyst is fabricated by solvothermal impregnation of ZnO on W18O49 for photocatalytic CO2 N-formylation of aniline. The localized surface plasmon resonance effect of W18O49 improves the absorption capacity for long-wave light significantly, and the hot electrons generated in W18O49 with a high energy can migrate to the conduction band of ZnO and thus enhance the photocatalytic reduction ability. Meanwhile, the S-scheme heterojunction facilitates the separation of photoinduced charge carriers and preserves the redox ability of W18O49/ZnO composite photocatalyst. The conversion of aniline reaches 99.1% after 5 h reaction under visible light irradiation at room temperature with an N-formylaniline selectivity of 100%. A possible photocatalytic reaction mechanism is proposed. This study paves a promising way for the design of highly efficient photocatalyst and the sustainable utilization of CO2.Peer reviewe
Hybrid synthetic/natural fiber-reinforced strain-hardening magnesia-based composites
No full textPublisher Copyright: © 2024 Elsevier LtdSynthetic fiber-reinforced strain-hardening magnesia (MgO)-based composites (SHMC) are an emerging group of fiber-reinforced cementitious composites (FRCC) with ultra-high ductility and CO2 sequestration potential. However, the size of SHMC members is limited by the inadequate carbonation depth of the MgO matrix. In this work, hybrid synthetic/natural fiber-reinforced SHMC are developed containing different contents of PVA fibers (0–2 vol%) and sisal fibers (0–4 vol%). The new Hybrid-SHMC were experimentally studied on micro-scale and composite scale. On the micro-scale, the effect of cement matrix carbonation on the PVA/sisal fiber-to-matrix interfacial bonds and the matrix moduli were studied by single-fiber pullout test and local nano-indentation. On the composite scale, the effect of fiber dosage on the compressive/tensile behavior and carbonation profile of SHMC were studied. The effects of the carbonation-induced micromechanical enhancements on the composite behaviors were validated by a micromechanics-based fiber-bridging model. The results demonstrated that the new hybrid SHMC could achieve ultra-high tensile ductility (> 2.5 %) and uniform carbonation simultaneously (≥ 0.25 g CO2/g MgO at different depths). In Hybrid-SHMC, the PVA fibers mainly contributed to the mechanical crack-bridging and thus strain-hardening, while sisal fibers with porous microstructure improved the carbonation depth and thus the fiber-matrix interfacial bonds, composite compressive, and tensile performances.Peer reviewe
Computational Analysis of Communicative Acts for Understanding Crisis News Comment Discourses
No full textSocial media analyses using computational methods are becoming increasingly important, especially for crisis communication and social media monitoring. We seek to investigate the validity and utility of computationally analyzing communicative acts in social media crisis news comment discourses. We implement an applied act classifier for a novel online context by utilizing few-shot learning and a small manually annotated dataset. To illustrate the usefulness of analyzing communicative acts, we show that how people use acts in comments notably changes across the crisis timeline. In contrast to classic crisis research, early social media crisis responses in our study do not show a heightened use of acts oriented to discursive struggle only, but instead resolution oriented acts are most common at first. In further analysis, we show that computational analysis of acts can complement traditional content analyses to reveal more specific insights on the functions and goals of comments. Our study paves the way for more fine-grained approaches to understanding social media discourses and crisis responses, offering potential new tools for crisis management.Peer reviewe
Social, environmental, and economic value in sustainable fashion business models
No full textPublisher Copyright: © 2024 Elsevier LtdThe aim of this paper is to advance research on sustainability within the fashion industry by explaining the combinations of social, environmental, and economic values that form the basis of sustainable business models in the Nordic fashion industry and to identify the main challenges fashion companies face in developing such models, given the limitations in current literature. Through an industry-focused case study of the Nordic fashion industry, recognized for its homogeneity and sustainability leadership, this study investigates how Nordic fashion companies collectively create value through the lens of the value mapping tool. The study adopts an inductive approach through eleven in-depth interviews with experts, managers, and owners. Additionally, it integrates secondary data derived from published information, enhancing the understanding of what sustainable business models in the Nordic fashion industry entail. The analysis enabled the identification of twenty-six elements related to the durability and longevity of products and gender-neutral and timeless design. The results suggest that a more holistic approach to sustainability is needed to facilitate the companies’ move from unsustainable business models to more sustainable ones. This article contributes to the literature by identifying broader patterns of value creation, value delivery, and value capture within the Nordic fashion industry. Furthermore, it enhances knowledge of social and environmental actions surrounding and examines barriers to sustainability activities. The practical contribution arises from the provision of a better understanding of the key elements in sustainable fashion business models of Nordic fashion companies, and thus, it is relevant to academia, practitioners, and policymakers.Peer reviewe
From structural to transition effects: Institutional dynamism as a deterrent to long-term investments by MNEs
No full textThe effect of institutional change on foreign direct investment is often conceptualized through the lens of an improving or deteriorating level of institutional quality that alters transaction costs. However, in the context of comprehensive government intervention in the past decades, this perspective ignores the potential uncertainties and costs associated with the process of institutional change. We propose that institutional change causes structural changes in transaction costs as well as accompanying transition effects due to uncertainty and learning costs. The extent of such transition effects is linked to the process characteristics of institutional change, e.g., institutional dynamism. In this paper, we examine the effects of institutional dynamism on foreign direct investment in long-term capital commitments and hypothesize a negative relationship between institutional dynamism and FDI, and a moderating effect of institutional dynamism on the relationship between institutional quality and FDI. Using investment data by US MNEs aggregated on the host country level, we find support for our hypotheses with some qualifications. We derive implications for the middle-income trap discussion as well as the ongoing fast-paced transition towards a sustainable global economy that is bound to shift attention from differences in the level of institutional quality towards differences in transition processes.Peer reviewe
Syngas Conversion to Higher Alcohols via Wood-Framed Cu/Co-Carbon Catalyst
No full textPublisher Copyright: © 2025 American Chemical Society.Syngas conversion into higher alcohols represents a promising avenue for transforming coal or biomass into liquid fuels. However, the commercialization of this process has been hindered by the high cost, low activity, and inadequate C2+OH selectivity of the catalysts. Herein, we have developed Cu/Co carbon wood catalysts, offering a cost-effective and stable alternative with superior selectivity for catalytic conversion. The formation of Cu/Co nanoparticles was found, influenced by water-1,2-propylene glycol ratios in the solution, resulting in bidisperse nanoparticles. The Cu/Co-CW-W1P1 catalyst (the ratio between water and 1,2-propanediol is 0.5:0.5) exhibited a remarkable CO conversion rate of 74.8% and a selectivity of 58.7% for C2+OH, primarily comprising linear primary alcohols. This catalyst demonstrated enduring stability and selectivity under industrial conditions, maintaining its efficacy for up to 350 h of operation. We also employed density functional theory (DFT) to analyze selectivity, particularly focusing on the binding strength of CO, a crucial intermediate for subsequent reactions leading to the formation of alcohols. DFT identified the pathway of CHx and CO coupling, ultimately yielding C2H5OH. This computational understanding, coupled with the high performance of the Cu/Co-carbon wood catalyst, paves the way to develop catalytically selective materials tailored for higher alcohol production from a nature-based source.Peer reviewe
3D reconfigurable hydroxylated carbon nanotubes-based water evaporators with long-distance transportation for continuous vapor generation
No full textPublisher Copyright: © 2024 Elsevier B.V.Utilizing solar-thermal power for water purification through interfacial solar steam generation represents an environmentally friendly approach to secure a clean water source. However, it is still challenging to simultaneously overcome short transport distances, low transport rates, and unsatisfactory solar-thermal energy conversion efficiency, as well as the salt accumulation problem. In this work, three-dimensional (3D) reconfigurable water evaporators are developed based on commercial fabric strings and hydroxylated carbon nanotubes. The specifically designed 3D architecture enables the fabric strings to have a long water transport distance and localized focusing of solar light that benefits the fabrication of 3D evaporators and water isolation with low heat loss. Besides, the hydroxylated carbon nanotubes with strong hydrophilicity as well as their inherent black color show high solar-heat conversion efficiency. A high evaporation rate of 3.234kg m-2h−1 is found and a solar-to-vapor efficiency of 123.21 % is also achieved by using a vertical evaporation structure due to the enlarged surface area allowing absorption of heat from the environment. Meanwhile, the accumulated salts do not block the water transport pathway and they can be easily removed in high-salinity water evaporation by employing the assembled rotating evaporator. The results suggest that the fabric rope is a good platform for exploring highly efficient evaporation structures. Combined with hydroxylated carbon nanotubes, as-designed 3D reconfigurable evaporators are promising for efficient freshwater generation.Peer reviewe
Operando and in situ APXPS investigation of the atomic layer deposition of a metal oxide coating on a Ni-rich cathode
No full textPublisher Copyright: © 2025 The AuthorsThe expansion of the electric vehicle industry is driving increased demand for lithium-ion batteries (LIBs), which in turn creates challenges in material availability and waste management that more durable LIBs could address. Electrode surface coating helps extend LIB lifespan, with atomic layered deposition (ALD) as the preferred method due to its precise thickness control and ability to coat various substrates. However, despite the extensive research on cathode modification via ALD, there is limited work on understanding the reaction mechanisms between precursors and unconventional substrates, such as composite electrodes. In this study, synchrotron-based ambient pressure X-ray photoelectron spectroscopy (APXPS) is employed to investigate the surface evolution of a LiNi0.8Mn0.1Co0.1O2 (NMC811) cathode during the initial stages of TiO2 formation via ALD. The operando and in situ APXPS data suggest that a hydroxylation step is essential for the initiation of TiO2 growth on a NMC811 composite electrode. The persistent appearance of –CF2 peaks implies that the deposition does not occur on the polymer binder. The findings of this study offer a deeper understanding of the surface chemistry during ALD half-cycles on cathode substrates, aiding in the optimization of the deposition process.Peer reviewe