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Development of efficient and robust electrocatalysts is critical for practical fuel cells. We report one-dimensional bunched platinum-nickel (Pt-Ni) alloy nanocages with a Pt-skin structure for the oxygen reduction reaction that display high mass activity (3.52 amperes per milligram platinum) and specific activity (5.16 milliamperes per square centimeter platinum), or nearly 17 and 14 times higher as compared with a commercial platinum on carbon (Pt/C) catalyst. The catalyst exhibits high stability with negligible activity decay after 50,000 cycles. Both the experimental results and theoretical calculations reveal the existence of fewer strongly bonded platinum-oxygen (Pt-O) sites induced by the strain and ligand effects. Moreover, the fuel cell assembled by this catalyst delivers a current density of 1.5 amperes per square centimeter at 0.6 volts and can operate steadily for at least 180 hours.

In recent years, noble metals atomically dispersed on solid oxide supports have become a frontier of heterogeneous catalysis. In pursuit of an ultimate atom efficiency, the stability of single-atom catalysts is pivotal. Here we compare two Pd/CeO 2 single-atom catalysts that are active in low-temperature CO oxidation and display drastically different structural dynamics under the reaction conditions. These catalysts were obtained by conventional impregnation on hydrothermally synthesized CeO 2 and one-step flame spray pyrolysis. The oxidized Pd atoms in the impregnated catalyst were prone to reduction and sintering during CO oxidation, whereas they remained intact on the surface of the Pd-doped CeO 2 derived by flame spray pyrolysis. A detailed in situ characterization linked the stability of the Pd single atoms to the reducibility of the Pd–CeO 2 interface and the extent of reverse oxygen spillover. To understand the chemical phenomena that underlie the metal–support interactions is crucial to the rational design of stable single-atom catalysts. Single-atom catalysts have become a frontier of heterogeneous catalysis, but to achieve a high stability under turnover is often a challenge. Now, a Pd/CeO 2 single-atom catalyst prepared using flame spray pyrolysis is able to stabilize the isolated Pd species during CO oxidation due to a high mobility of surface lattice oxygen.

Understanding the performance of subnanometer catalysts and how catalyst treatment and exposure to spectroscopic probe molecules change the structure requires accurate structure determination under working conditions. Experiments lack simultaneous temporal and spatial resolution and could alter the structure, and similar challenges hinder first-principles calculations from answering these questions. Here, we introduce a multiscale modeling framework to follow the evolution of subnanometer clusters at experimentally relevant time scales. We demonstrate its feasibility on Pd adsorbed on CeO 2 (111) at various catalyst loadings, temperatures, and exposures to CO. We show that sintering occurs in seconds even at room temperature and is mainly driven by free energy reduction. It leads to a kinetically (far from equilibrium) frozen ensemble of quasi-two-dimensional structures that CO chemisorption and infrared experiments probe. CO adsorption makes structures flatter and smaller. High temperatures drive very rapid sintering toward larger, stable/metastable equilibrium structures, where CO induces secondary structure changes only. Understanding the catalysts’ structure evolution under working conditions is challenging. Here the authors use a multiscale simulation approach and machine learning to study the structures and nucleation of CeO 2 -supported Pd clusters and single atoms at various catalyst loadings, temperatures, and exposures to CO.

Ionic-conductive polymers are appealing electrolyte materials for solid-state lithium-based batteries. However, these polymers are detrimentally affected by the electrochemically-inactive anion migration that limits the ionic conductivity and accelerates cell failure. To circumvent this issue, we propose the use of polyvinyl ferrocene (PVF) as positive electrode active material. The PVF acts as an anion-acceptor during redox processes, thus simultaneously setting anions and lithium ions as effective charge carriers. We report the testing of various Li||PVF lab-scale cells using polyethylene oxide (PEO) matrix and Li-containing salts with different anions. Interestingly, the cells using the PEO-lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) solid electrolyte deliver an initial capacity of 108 mAh g −1 at 100 μA cm −2 and 60 °C, and a discharge capacity retention of 70% (i.e., 70 mAh g −1 ) after 2800 cycles at 300 μA cm −2 and 60 °C. The Li|PEO-LiTFSI|PVF cells tested at 50 μA cm −2 and 30 °C can also deliver an initial discharge capacity of around 98 mAh g −1 with an electrolyte ionic conductivity in the order of 10 −5  S cm −1 . The energy content of secondary batteries is often limited by the charge carriers available in the system. Here, the authors employed an anion acceptor cathode for simultaneous use of electrolyte anions and cations as effective charge carriers in solid polymer electrolytes for lithium-based batteries.

The inferior tolerance with reversible accommodation of large‐sized Na+ ion in electrode materials has plagued the adaptability of sodium‐ion chemistry. The sluggish diffusion kinetics of Na+ also baffles the desirability. Herein, a carbon fiber supported binder‐free electrode consisting of bismuth and carbon composite is designed. Well‐confined bismuth nanodots are synthesized by replacing cobalt in the metal–organic frameworks (MOF)–derived, nitrogen‐doped carbon arrays, which are demonstrated with remarkable reversibility during sodiation and desodiation. Cobalt species in the pristine MOF catalyze the graphitization around organic components in calcination, generating a highly conductive network in which the bismuth is to be embedded. The uniformly dispersed bismuth nanodots provide plenty boundaries and abundant active sites in the carbon arrays, where fast sodium storage kinetics are realized to contribute extra capacity and excellent rate performance. Bismuth nanodots are synthesized by confined replacement reaction with cobalt from metal–organic frameworks (MOF)‐derived templates on carbon fiber substrate. As binder‐free electrode for sodium‐ion batteries, nanosized bismuth can accommodate volume changes during sodiation/desodiation. The carbon arrays are with plenty phase boundaries and abundant active sites, which can contribute to extra capacity and excellent rate performance with fast capacitive sodium storage kinetics.

Hard carbons are promising anode materials for sodium‐ion batteries. To meet practical requirements, searching for durable and conductive carbon with a stable interface is of great importance. Here, we prepare a series of vanadium‐modified hard carbon submicrospheres by using hydrothermal carbonization followed by high‐temperature pyrolysis. Significantly, the introduction of vanadium can facilitate the nucleation and uniform growth of carbon spheres and generate abundant V–O–C interface bonds, thus optimizing the reaction kinetic. Meanwhile, the optimized hard carbon spheres modified by vanadium carbide, with sufficient pseudographitic domains, provide more active sites for Na ion migration and storage. As a result, the HC/VC‐1300 electrode exhibits excellent Na storage performance, including a high capacity of 420 mAh g−1 at 50 mA g−1 and good rate capability at 1 A g−1. This study proposes a new strategy for the synthesis of hard carbon spheres with high tap density and emphasizes the key role of pseudographitic structure for Na storage and interface stabilization. The HC/VC materials were synthesized by using hydrothermal carbonization followed by high‐temperature pyrolysis. The HC/VC‐1300 material has abundant V–O–C interface bonds and sufficient pseudographitic domains to provide more active sites for Na ion migration and storage, optimizing the reaction kinetics, resulting in good structural stability and excellent Na storage properties.

To systematically review the prophylactic and therapeutic interventions for reducing the incidence or severity of intestinal symptoms among cancer patients receiving radiotherapy. A literature search was conducted in the PubMed database using various search terms, including ‘radiation enteritis’, ‘radiation enteropathy’, ‘radiation-induced intestinal disease’, ‘radiation-induced intestinal damage’ and ‘radiation mucositis’. The search was limited to studies, clinical trials and meta-analyses published in English with no limitation on publication date. Other relevant literature was identified based on the reference lists of selected studies. The pathogenesis of acute and chronic radiation-induced intestinal damage as well as the prevention and treatment approaches were reviewed. There is inadequate evidence to strongly support the use of a particular strategy to reduce radiation-induced intestinal damage. More high-quality randomized controlled trials are required for interventions with limited evidence suggestive of potential benefits.

Much research has been invested in infrared temperature (IRT)-based methods for cotton ( Gossypium hirsutism L.) water stress detection using in-field sensors, but adoption of these is low, perhaps due to logistical challenges. Alternatively, the Water Deficit Index (WDI) was developed for crop water stress assessment using remote sensors not embedded in the canopy. The objective of this research was to evaluate the performance of a sensor package—including modern IRT and normalized difference vegetation index (NDVI) sensors facing downward at 45˚, and a mini weather station—attached unintrusively to a center pivot irrigation system for detecting cotton water stress using WDI. Sensor packages were evaluated in a two-year field study that included four irrigation treatments (0, 30, 60, and 90% ET replacement) and in two production cotton fields. Overall, the tested system was effective at distinguishing crop water stress among irrigation rates. Comparison of the results to a ground-based station and simulations indicated that WDI overestimated water stress at the highest irrigation rate, but performed well otherwise. Accuracy of the system could be improved by measuring canopy coverage ( Fc ) from the same vantage point as the IRT and NDVI sensors (from the pivot, downward at a 45˚ angle).

There are some drawbacks such as the propagation and spread of bacteria and viruses during the use of normal paper. Therefore, this work designed a starch styrene-acrylic antibacterial emulsion for improving the paper properties. The modified antimicrobial monomer was prepared by the subject-object recognition of β-cyclodextrin with hydrophobic modified titanium dioxide. The antibacterial performance of prepared emulsion was tested by Escherichia coli, Staphylococcus aureus. And the mechanical properties of the modified paper were measured according to the national standards. The results showed that the antibacterial emulsion has excellent comprehensive performance with the viscosity of 1750 mPa·s, the inhibition ring diameter of 11.82 mm, the good chemical stability and storage stability. Therefore, the proposed cationic starch styrene-acrylic antibacterial emulsion has promising applications in paper surface modification.

Objective This study aimed to investigate the microbiome profile in the cystic fluid of ovarian endometrioma and explore its association with the microbial communities present in the lower and upper reproductive tracts. Design A microbial analysis was conducted across multiple compartments of the reproductive tract in patients diagnosed with ovarian endometrioma. Subjects Sixteen female patients aged 25–43 years (mean age: 31.56 years) who underwent laparoscopic surgery for ovarian endometrioma at the First Hospital of Putian City between April 2023 and February 2024 were enrolled in this study. Main outcome measures 16S rDNA sequencing was employed to characterize the microbiome of ovarian endometrioma and assess its correlations with clinical symptoms, inflammatory markers, and serum CA125 levels Results Microbial communities were detected in the posterior vaginal fornix, endometrial fluid, peritoneal fluid, and cystic fluid, exhibiting distinct compositional profiles. Community diversity significantly increased along the anatomical gradient from the posterior vaginal fornix to endometrial fluid, peritoneal fluid, and cystic fluid, with the highest microbial diversity observed in the cystic fluid. Lactobacillus was the predominant genus in the posterior vaginal fornix, whereas Escherichia-Shigella was most abundant in endometrial fluid samples. Hydrogenophaga and Brevundimonas were the dominant taxa in both peritoneal and cystic fluids. Notably, the microbial composition of peritoneal fluid showed the greatest similarity to that of cystic fluid, and functional prediction analyses indicated largely overlapping biological functions between these two sites. Furthermore, Spearman correlation analysis revealed significant associations between specific microbial taxa and certain clinical manifestations or inflammatory factors. Conclusion This study demonstrates the presence of a unique and highly diverse microbiome within the cystic fluid of ovarian endometrioma. The site-specific microbial profiles and their correlations with clinical parameters suggest a potential role of microbiota in disease pathogenesis through inflammatory and metabolic mechanisms. These findings contribute novel insights that may inform future strategies for the prevention, diagnosis, and treatment of ovarian endometrioma.