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The long‐term operation of polymer electrolyte membrane fuel cells (PEMFCs) relies heavily on the durability of the perfluorinated sulfonic acid (PFSA, e.g., Nafion) membrane against chemical and mechanical degradation. To mitigate mechanical degradation, the introduction of a reinforcing matrix, such as a porous PTFE sheet, is employed. However, completely impregnating the PFSA ionomer into the PTFE sheet through the conventional blade‐coating method using a highly viscous ionomer solution proves challenging. This limitation results in decreased mechanical and proton transport properties. To reduce proton transport resistance, thinner membrane thickness is desirable, although it increases the amount of gas crossover, which generates radicals and accelerates the chemical degradation of the membrane. In this study, a spraying process utilizing a low viscous‐solvent‐rich ionomer solution is experimentally optimized to construct a well‐impregnated PTFE/Nafion membrane and analyzed using a simple theoretical droplet‐spreading model. Furthermore, an ultrathin graphene oxide (GO) layer is introduced during the membrane fabrication process with the same spraying technique for reducing gas crossover while minimizing performance loss. The membrane electrode assembly (MEA) with the prepared PTFE/Nafion membrane‐incorporated ultrathin GO layer shows significantly greater durability and initial performance compared to the conventional MEA. [ABSTRACT FROM AUTHOR]

The long‐term operation of polymer electrolyte membrane fuel cells (PEMFCs) relies heavily on the durability of the perfluorinated sulfonic acid (PFSA, e.g., Nafion) membrane against chemical and mechanical degradation. To mitigate mechanical degradation, the introduction of a reinforcing matrix, such as a porous PTFE sheet, is employed. However, completely impregnating the PFSA ionomer into the PTFE sheet through the conventional blade‐coating method using a highly viscous ionomer solution proves challenging. This limitation results in decreased mechanical and proton transport properties. To reduce proton transport resistance, thinner membrane thickness is desirable, although it increases the amount of gas crossover, which generates radicals and accelerates the chemical degradation of the membrane. In this study, a spraying process utilizing a low viscous‐solvent‐rich ionomer solution is experimentally optimized to construct a well‐impregnated PTFE/Nafion membrane and analyzed using a simple theoretical droplet‐spreading model. Furthermore, an ultrathin graphene oxide (GO) layer is introduced during the membrane fabrication process with the same spraying technique for reducing gas crossover while minimizing performance loss. The membrane electrode assembly (MEA) with the prepared PTFE/Nafion membrane‐incorporated ultrathin GO layer shows significantly greater durability and initial performance compared to the conventional MEA. [ABSTRACT FROM AUTHOR]

Nature-based solutions (NbS) is an approach to solving climate change and social issues based on nature. Despite NbS being widely studied as an effective method to solve social problems, the trends in NbS research have hardly been analyzed. Therefore, this study examined change patterns in NbS-related research topics over time and analyzed the interactions of NbS research and relevant activities in various fields. After reviewing research papers based on the search term 'nature-based solutions' on Scopus, and collecting 1567 research papers, we conducted dynamic topic modeling (DTM) and network analysis. The papers were classified into 19 topics via DTM. Water, forest, and urban topics made up the greatest portion of NbS research, while NbS topics in the forest sector showed a steady increase over time. This study also found close connections between NbS studies on forests and other sectors and confirmed that the forest sector can become an integrated means of contributing to climate change responses and other resultant social issues. This study demonstrates that DTM and network analysis are useful tools for understanding the trends in NbS research and finding the linkages between various fields. [ABSTRACT FROM AUTHOR]

For achieving economically viable polymer electrolyte membrane fuel cells (PEMFCs) in the commercial market, simplifying the fabrication process and manufacturing of robust membrane electrode assembly (MEA) are important. Herein, a single spray‐coating method for developing a robust and free‐standing reinforced Nafion composite membrane and electrodes is reported. By comparing the fabricated membrane's morphology under diverse process conditions including the nozzle‐to‐substrate distance and solution‐loading rates, the optimized spray‐coating for uniformly deposited spray‐based membrane without any defects has been determined. To explain this optimized condition, a simple theoretical model based on the concept of the surface coverage of sprayed droplets is proposed. The fabricated multiwalled carbon nanotubes/CeO2‐reinforced Nafion composite membrane shows excellent mechanical properties with minimal proton‐conducting loss despite using additional fillers of total 4 wt% in the Nafion matrix. By successively depositing the catalyst layer on that membrane using the same spray‐coating device, an MEA with the reinforced spray‐based membrane has been successfully fabricated; moreover, diverse electrochemical measurements and durability tests have been conducted. The MEA with the reinforced membrane shows comparable initial performance and considerably higher performance after the durability test compared to the MEA with commercial Nafion membrane. [ABSTRACT FROM AUTHOR]

Frailty lacks a universal definition. The modified Frailty Index (mFI) using patient comorbidities can be used to measure frailty. We hypothesized that mFI predicts 30-day complications after microsurgical breast reconstruction. American College of Surgeons’ (ACS) National Surgical Quality Improvement Project (NSQIP) was investigated to identify patients undergoing microsurgical breast reconstruction between 2005–2014 using Current Procedure Terminology (CPT) code, 19364. We used mFI as a measure of frailty. The patients were assigned a frailty score based on the number of preoperative comorbid conditions as defined by the mFI. Other risk indices used include age, BMI, wound class, ASA class. Stratification was performed in ascending order for each. The outcome measure was aggregate 30-day complications. Regression analysis was performed followed by Receptor Operating Characteristic (ROC) curve to determine the accuracy of each risk index in predicting 30-day complications. Of the 3237 patients 24% experienced complications. Univariate logistic regression analysis found odds ratio of complications for frailty score 1=22.1 (CI = 17.9–27.3, p<0.01), and 2=28 (CI = 18.3–43, p<0.01) compared to frailty score = 0. ROC curve demonstrated mFI with the highest concordance score (c-score = 0.816). Multivariable logistic regression found frailty as the strongest independent predictor of 30-day aggregate complications adjusted OR = 22.24, CI = 17.77–27.82, p<0.01 when compared to other risk indices. The modified Frailty Index is a simple, reliable, and objective tool that can be used to predict postoperative complications after microsurgical breast reconstruction. The application of this tool can help microsurgeons preoperatively identify patients who are at high risk. [ABSTRACT FROM AUTHOR]

Incorporating inorganic fillers, such as SiO 2 , TiO 2 , and CeO 2 , into the electrolyte membrane via the conventional casting and evaporation process is proved to intensify the water retention, thus improve the proton conductivity of the polymer electrolyte membrane (PEM) under high temperature. However, this approach does not dramatically enhance the performance of the composite membrane due to the issue of proton pathway reduction and fillers agglomeration. Herein, uniformly patterned mesoporous TiO 2 microplates (PTMPs) are successfully embedded on the anode side surface of the Nafion® membrane by using micro-hole stencil for spatially localizing the PTMPs and well-controlled ionomer spray technique. Interestingly, the membrane comprised of PTMPs with a diameter of ∼50 μm and a height of ∼5.2 μm exhibits the maximum power density by more than 35.2% compared to the reference Nafion® membrane with the same thickness (∼25 μm) under 120 °C and relative humidity of 35% condition. The result indicates that suitably designed PTMPs-embedded Nafion® membrane is effective for improving the PEMFC performance under elevated temperature and low humidity conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Samples with compositions of 95 wt% Mg + 5 wt% CMC (Carboxymethylcellulose, Sodium Salt) (named Mg-5CMC) and 90 wt% Mg + 10 wt% CMC (named Mg-10CMC) were prepared through milling in a hydrogen atmosphere (transformation-involving milling). After activation, Mg-5CMC had a larger amount of hydrogen absorbed in 60 min, U (60 min), than Mg-10CMC and milled Mg at 593 K. At the cycle number (CN) of four, Mg-5CMC had a very high beginning hydrogen uptake rate (1.45 wt% H/min) and a very large effective hydrogen-storage capacity of about 7.4 wt%. Mg-5CMC released 4.76 wt% H in 60 min at 648 K in hydrogen of 1.0 bar. It is believed that CMC melted during milling, and that since CMC has high viscosity, sliding between Mg particles and hardened steel balls was prevented, leading to effective milling (generation of defects and cracks and reduction of particle size). As far as we know, this study is the first in which a polymer CMC was added to Mg to improve the hydrogen uptake and release properties of Mg. Graphical abstract Image 1 Highlights • Preparation of a polymer Carboxymethylcellulose (CMC)-added Mg alloy by milling in hydrogen. • Hydrogen-storage capacity of about 7.4 wt% by activated Mg-5CMC at 593 K in hydrogen of 12 bar. • A very high initial hydrogen uptake rate of 1.45 wt% H/min at 593 K in 12 bar hydrogen after activation. • Addition of CMC is more effective than additions of halogen compounds, oxides, or metals. • First study where CMC is added by milling in hydrogen to improve hydrogen-storage properties of Mg. [ABSTRACT FROM AUTHOR]

• Addition of Ni by milling in hydrogen to increase dehydrogenation rates of Mg-5graphene. • Significantly higher initial hydrogenation and dehydrogenation rates than Mg-5graphene. • A very high effective hydrogen-storage capacity of approximately 7 wt% at the second cycle. • Increase in Mg crystallite size (decrease in the grain boundary) decreased rates with cycling. • Milling and introduction of heat during cycling led to partial change of graphene to C60 fullerene. Ni was added to increase the dehydrogenation rates of graphene-added Mg with a composition of 95 wt% Mg + 5 wt% graphene (named Mg-5graphene). For this, samples with a composition of 95 wt% Mg + 2.5 wt% Ni + 2.5 wt% graphene (named Mg-2.5Ni-2.5graphene) were prepared by ball milling in hydrogen. Mg-2.5Ni-2.5graphene had significantly higher initial hydrogenation and dehydrogenation rates, with significantly larger quantities of hydrogen absorbed and released over 60 min, than Mg-5graphene. Mg-2.5Ni-2.5graphene exhibited a very high effective hydrogen-storage capacity of approximately 7 wt% at the second cycle (n = 2). We believe that the increase in the Mg crystallite size, leading to a decrease in the grain boundaries, with cycling contributed partly to decreases in the hydrogenation and dehydrogenation rates as n increases. We attributed the partial transformation of graphene into C60 fullerene to the processing of reactive ball milling and the introduction of heat during cycling. [ABSTRACT FROM AUTHOR]

Summary: Improving the durability of the membrane electrode assembly (MEA) while obtaining high performance is required to further commercialize polymer electrolyte membrane fuel cells (PEMFCs). The durability of PEMFCs is improved by incorporating radical scavengers, such as CeO2 (ceria), into the MEA, especially the membrane. However, nanosized ceria particles are generally mixed with ionomers and are cast on substrates to fabricate composite membranes. In such a case, controlling their morphology and avoiding particle agglomeration is difficult. Herein, we report a novel method for constructing a robust membrane by incorporating ultrathin ceria barriers into the outermost sides of a commercial Nafion membrane to effectively alleviate radical attacks while ensuring the high uniformity and controllability of ceria layers. The improved durability of the composite membrane is confirmed via ex situ Fenton's test and in situ operation of a fuel cell. Moreover, we observe that the amount of fluoride ion emission and the loss of proton conductivity of the membranes decrease as the CeO2 density increases. The MEA comprises a modified membrane with CeO2 barriers that show proper areal density. It demonstrates excellent durability under accelerated environmental conditions (open circuit voltage test) and acceptable initial performance with an insignificant decrease in proton conductivity. [ABSTRACT FROM AUTHOR]

• Assessing ecosystem services with land cover change scenarios can support Indonesian peatland restoration. • Resotration of can add $2.38 billion from Current $75.41 billion economic value of the peatlands of Jambi and Sumatra Selatan. • Developing forest and wetland restoration scenario has higher benefits comparing the current status and business as usual. • More international restoration efforts are required for sustainable land use management in Indonesian peatlands. Conserving tropical forests and peatlands is considered a key strategy for international forest project cooperation and the promotion of carbon neutrality. Focusing on peatlands in the Sumatra Selatan and Jambi provinces in Indonesia, this study aimed to assess land-cover changes from 1992 to 2020 and associated ecosystem services to assist in the development of effective forest and peatland-related projects. This study first analyzed the historical land-cover changes as a baseline for establishing potential project scenarios. Carbon storage, habitat suitability, water yield, and crop production were selected as the key ecosystem services in the peatlands, and these were assessed for the current land cover and two possible project scenarios in 2050 – business-as-usual (BAU) and forest and wetland restoration (FOR) – using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) tool. In terms of land-cover changes, the area of forests and wetlands decreased, but that of agriculture, grassland, and built-up areas increased in the peatlands. Based on the land-cover scenarios, the carbon storage, habitat suitability, water yield, and crop production varied on 2.32–2,74 billion tC, 92.02–93.46 %, 16.45–16,91 billion m3, and 2.34–2.73 million ton, respectively. The total economic value of the ecosystem services for the current land cover was $75.41 billion, while that predicted for BAU and FOR was estimated to be $70.59 billion and $77.79 billion, respectively. Restoration plans have the environmental and economic benefit of provincial-level assessment, so the development of appropriate projects for tropical forest and peatland conservation and restoration is necessary for international cooperation projects. [ABSTRACT FROM AUTHOR]

[Display omitted] • Selected model binary composite electrode is AC / PEDOT:PSS. • Electrochemical thermopower in the composite is proportional to the mass fraction. • The proportionality holds despite nonlinear capacitance and mass fraction relation. • PEDOT:PSS has high thermopower electrode of + 14 mV/K. Recent progress in electrochemical waste heat harvesting technology has drawn attention owing to its high thermopower, typically > 1 mV/K, leading to high heat-to-electricity conversion efficiency. One of the key merits is that it can adopt chemistry and manufacturing techniques from already existing supercapacitors. However, they typically require electrodes in composite forms and the rule that determines the electrochemical thermopowers of such composites remains unknown to this date. This work experimentally demonstrates that the electrochemical thermopower of the poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) / activated carbon (AC) model composite electrode is proportional to mass fraction of the respective constituents. This rule imposes a ceiling in the electrochemical thermopower of composites, where the largest thermopower among the constituents is the maximum that the composite can possibly achieve. This proportionality rule can serve as a design guideline for electrochemical heat harvesters deriving from supercapacitors in the future. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Preparation of a polymer Carboxymethylcellulose (CMC)-added Mg alloy by milling in hydrogen. • Hydrogen-storage capacity of about 7.2 wt% by activated Mg-5CMC at 593 K in hydrogen of 12 bar. • A very high initial hydrogen uptake rate of 1.45 wt% H/min at 593 K in 12 bar hydrogen after activation. • Addition of CMC is more effective than additions of halogen compounds, oxides, or metals. • First study where CMC is added by milling in hydrogen to improve hydrogen-storage properties of Mg. Abstract Carboxymethylcellulose sodium salt (CMC) was added to magnesium via milling in hydrogen (transformation-involving milling), and samples with compositions of 95 wt% Mg + 5 wt% CMC (named Mg-5CMC) and 90 wt% Mg + 10 wt% CMC (Mg-10CMC) were prepared. At the cycle number (CN) of three, Mg-5CMC had a very high initial hydrogenation rate (1.45 wt% H/min) and a very large effective hydrogen-storage capacity of about 7.2 wt%. It is believed that the CMC melted during milling, and that because the melted CMC was highly viscous, sliding between the Mg particles and hardened steel balls was prevented, which led to effective milling (the generation of defects and cracks and the reduction of particle sizes). To the best of our knowledge, this study is the first in which a polymer CMC was added to Mg in order to improve the hydrogenation and dehydrogenation properties of Mg. [ABSTRACT FROM AUTHOR]

Aerial roots are a vital feature that allow mangroves to survive in anaerobic and unstable soil conditions. Mangrove species have different aerial root characteristics and show their own site-specific distribution. The distribution of three types of aerial roots with different morphological characteristics was investigated between accretion and erosion sites in Ca Mau, Vietnam. Stilt roots, pneumatophores and knee roots were the three main aerial root types in the study area. Stilt roots of Rhizophora apiculata BL. and pneumatophores of Avicennia species were the two most abundant root types at the study sites, dominating erosion and accretion sites, respectively. Stilt roots had a higher number of primary roots in seaward plots than in landward plots (p < 0.05), supporting the ability of R. apiculata to withstand erosion of the surface. Tidal erosion moved away sediment and exposed roots, which resulted in higher aboveground stilt root height in seaward plots than in landward plots at erosion sites (p < 0.05). The higher density and biomass of pneumatophores in seaward plots than those in landward plots at accretion sites (p < 0.05) confirmed the adaptation of Avicennia to newly accreted sites where tidal inundation and anaerobic conditions limited mangrove growth. The density of A. alba decreased with the distance from the sea at both erosion and accretion sites, implying that this species was a pioneer species adapted to newly accreted sites or disturbed sites among mangrove species. Bruguiera parviflora with knee roots was distributed in more stable conditions. Mangrove species with different root types displayed a zonal distribution with increasing distance from the shoreline. This distribution reflects mangrove species adaptabilities and species-specific roles in the context of coastal processes and site conditions, which should be considered in coastal mangrove restoration. • The distribution of three types of aerial roots with different morphological characteristics was investigated between accretion and erosion sites. • The different aerial root types support different mangrove species distribution between accretion and erosion sites. • Stilt roots support Rhizophora apiculata to withstand erosion. • Pneumatophore roots enable Avicennia to stand tidal inundation and anaerobic conditions and invade newly accreted sites. • The distribution of mangrove species reflected mangrove stand development, interacting with coastal processes and site conditions. [ABSTRACT FROM AUTHOR]

〈100〉 axes of the rod-shaped grains of laser irradiated cold-rolled 3.04%-Si steel sheets are parallel to either solidification direction or normal direction of the steel sheet. The portion of desirable textures was enhanced by controlling of atmosphere and the direction of heat flow. The area fraction of the texture, which has 〈100〉 axis parallel to normal direction of the steel sheet, in the laser-affected steel sheets in air and argon atmosphere increased up to 23.4% and 26.3%, respectively, compared to a conventionally annealed steel sheet (8.2%). [ABSTRACT FROM AUTHOR]