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Shifting from the typical 4e– pathway to H2O in electrochemical oxygen reduction to the 2e– pathway to H2O2 is increasingly recognized as an environmentally friendly approach for producing H2O2. However, the competitive 4e− pathway is a significant obstacle to the production of H2O2 since H2O is the thermodynamically favored product. Here, a series of Pt, Pd, and Rh active atoms diluted within inert‐Au matrices with precisely controlled atomic arrangements and coordination environments are synthesized via facet engineering for O2‐to‐H2O2 production. Surprisingly, individually dispersed Pt atoms within the Au surface enclosed by the square atomic arrangements exhibit superior H2O2 selectivity and achieve a maximum selectivity of 90% at 0.36 V versus the reversible hydrogen electrode. Operando synchrotron ambient pressure X‐ray photoelectron spectroscopy identifies the presence of *OOH key intermediates on these isolated Pt active sites. Grand canonical density‐functional theory also reveals that the kinetic energy barrier for the 2e− pathway (0.08 eV; OOH* + H+ + e− → H2O2) on the isolated Pt sites is significantly lower than the 4e− pathway (0.29 eV; OOH* + H+ + e− → O* + H2O). This work enables atomic‐scale control in dilute binary alloy surfaces with specific configurations of isolated active atoms and provides essential guidance for catalyst design to boost O2‐to‐H2O2 production. [ABSTRACT FROM AUTHOR]

The electron waves of a host system exhibit an oscillating response to an external impurity, namely Friedel oscillations (FOs), extensively studied in two-dimensional materials. Recently, wavefront dislocations, a new feature of FOs, have been revealed in graphene. However, previous analytical works have been limited to the linear dispersion of graphene. Herein, the fate of wavefront dislocations is investigated numerically in FOs beyond the linear regime. The wavefront dislocations are robust against the trigonal warping effect, crucial for high doping graphene, due to the invariant winding number of the tight-binding energy band. Furthermore, the opening of the gap, increasing the electronic Fermi wavelength, can highlight the wavefront dislocations blurred by intravalley scattering-induced short-range oscillations. These results should be observable using current experimental technology. Therefore, this study not only demonstrates the robust existence of wavefront dislocations in FOs over a wide range of energies but also deepens the understanding of intervalley scattering in graphene and other twodimensional valleytronic materials. [ABSTRACT FROM AUTHOR]

Late spring coldness has a profound impact on yield and quality of wheat (Triticum aestivum), the reasonable fertilization management significantly improved yield, quality, and cold resistance of plants. Here, 10 predominant wheat varieties cultivated in the Huang‐Huai‐Hai region were selected to investigate the detrimental influence mechanism of late spring coldness on wheat growth and screen three varieties with a strong resistance to coldness. Additionally, under late spring coldness, the three varieties were applied with varying ratios of base to topdressing nitrogen fertilizer to investigate the consequences on the establishment of population structure and subsequent formation of yield and quality. The results showed that late spring coldness exerted severely detrimental effect on wheat organs development, including the increased occurrence of dead tillers, elevated mortality of young spikes, and significant decrease kernels. However, compared to N1 treatment (a nitrogen fertilizer distribution of 100% base+0% jointing+0% booting), the N2 treatment (50% base+50% jointing+0% booting) exhibited favorable outcomes under late spring coldness, such as the decreased basic seedlings and tillers, increased flag leaf area, and leaf area index, contributing to the higher spike number, grain number, and 1000‐kernel weight. Ultimately, the grain yields of Jinan 17, Huaimai 28, and Yan'nong 5158 reached their maximum values, with a 23.5%, 10.6%, and 24.2% increase, respectively, and the membership function analysis confirmed the most favorable effect of N2 treatment. These findings underscore the appropriately increased ration of topdressing nitrogen fertilizer during late spring coldness as a prerequisite for achieving both high yield and good quality of wheat. Core Ideas: Late spring coldness exerted severely detrimental effects on wheat organs development.The delayed proportion of nitrogen enhances the toughness of wheat dough in terms of stability and formation time.Adjusting ration of topdressing nitrogen can improve yield‐related trains of wheat during late spring coldness. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusions Melasma is a prevalent pigmented disease, yet its pathogenesis remains unclear, posing challenges for effective treatment. Bibliometric analysis, a novel approach to literature research, offers the opportunity to evaluate research trends through qualitative and quantitative methods. This study utilizes bibliometric methods to analyze the existing literature on melasma treatment, examining influential publications, institutions, countries, and authors through statistical analysis.In order to retrieve manuscripts related to the topic of melasma treatment, we conducted a search using the search formula: (TS = (melasma or Chloasma or “mask of pregnancy”)) AND TS = (treatment or therapy). We searched through the Web of Science Core Collection database, covering publications from 2000 to 2023. VOSviewer, CiteSpace and the Bibliometric online site (https://bibliometric.com/app) were used to conduct this bibliometric analysis. Our analysis focused on various factors including publications, authors co‐authorship, institutions, countries, citation analysis, keywords co‐occurrence, references co‐citation and journal co‐citation.A total of 943 articles and 200 reviews were published between 2000 and 2023, accumulating a total of 8628 citations. The average number of citations per item was 18.85, and the average number of citations per year was 292.69. The most prolific author, Sungeun Chang, contributed a total of 9 articles. Cario University emerged as the top research institution. The United States led in terms of article publications with a count of 276. In the past 5 years, the research trends in this field have primarily focused on tranexamic acid and epidermal melasma, as indicated by the burst analysis of publications and keywords.The United States continues to lead in terms of institutions and research output. The current emphasis is on the meticulous implementation of tranexamic acid and laser therapy. It is crucial to foster enhanced collaboration among countries, institutions, and authors to facilitate improved research. [ABSTRACT FROM AUTHOR]

The design and synthesis of polyhedra using coordination‐driven self‐assembly has been an intriguing research area for synthetic chemists. Metal‐organic polyhedra are a class of intricate molecular architectures that have garnered significant attention in the literature due to their diverse structures and potential applications. Hereby, we report Cu‐MOP, a bifunctional metal‐organic cuboctahedra built using 2,6‐dimethylpyridine‐3,5‐dicarboxylic acid and copper acetate at room temperature. The presence of both Lewis basic pyridine groups and Lewis acidic copper sites imparts catalytic activity to Cu‐MOP for the tandem one‐pot deacetalization‐Knoevenagel/Henry reactions. The effect of solvent system and time duration on the yields of the reactions was studied, and the results illustrate the promising potential of these metal‐organic cuboctahedra, also known as nanoballs for applications in catalysis. [ABSTRACT FROM AUTHOR]