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Silicon, renowned for its remarkable energy density, has emerged as a focal point in the pursuit of high-energy storage solutions for the next generation. Nevertheless, silicon electrodes are known to undergo significant volume expansion during the insertion of lithium ions, leading to structural deformation and the development of internal stresses, and causing a rapid decline in battery capacity and overall lifespan. To gain deeper insights into the intricacies of charge rate effects, this study employs a combination of in situ measurements and computational modeling to elucidate the cyclic performance of composite silicon electrodes. The findings derived from the established model and curvature measurement system unveil the substantial alterations in stress and deformation as a consequence of varying charge rates. Notably, the active layer experiences compressive forces that diminish as the charge rate decreases. At a charge rate of 0.2, the active layer endures a maximum stress of 89.145 MPa, providing a comprehensive explanation for the observed deterioration in cycling performance at higher charge rates. This study not only establishes a fundamental basis for subsequent stress analyses of silicon electrodes but also lays a solid foundation for further exploration of the impact of charge rates on composite silicon electrodes. [ABSTRACT FROM AUTHOR]

Revealing the mechanisms underlying community organization has long been a central interest for ecologists and biogeographers. Recent findings have suggested that different dimensions of biodiversity may be shaped by contrasting ecological processes, offering complementary insights about community assembly. However, studies integrating multiple diversity facets across the Qinghai‐Tibetan Plateau (QTP) remain insufficient. We combined multiple analytical frameworks to unravel the patterns (taxonomic, functional and phylogenetic) and correlates (local environment, land use and dispersal pathways) of aquatic arthropod diversity in lotic (stream) and lentic (wetland) ecosystems of the QTP. We observed strong phylogenetic signals in most functional traits, pointing to the influence of evolutionary processes on these faunas. Null models indicated that community structure in most streams and wetlands was mostly the result of random draws from the regional functional and phylogenetic species pool. The prevalence of stochasticity was most likely associated with the interplay of the paleogeographical history, the extremely harsh environmental conditions at high elevations and the subsequent impoverishment of the regional species pool. However, some streams and wetlands also exhibited phylogenetic overdispersion and functional clustering, emphasizing the potential importance of competitive exclusion and habitat filtering, respectively. Variation partitioning further revealed that both environmental filtering and dispersal limitation accounted for the spatial variation of diversity measures, with local environment overriding the effects of space and catchment land use. Overall, this study improves our understanding of community organization and diversity patterns in environmentally extreme alpine catchments, with broad implications for the conservation and management of one of the world’s most important high‐altitude treasures. [ABSTRACT FROM AUTHOR]

The holarctic genus Mesenchytraeus is one of the species‐rich genera in the family Enchytraeidae. Changbai Mountain supports high diversity of Mesenchytraeus species, making it an ideal area to explore species boundaries. We explored species boundaries of Mesenchytraeus using an integrative approach. Morphological taxonomy recognized 10 species in this region, five of them new to science. In contrast, molecular species delimitation analyses showed that there are at least 16 species, 11 of them new to science. Clear genetic gaps were observed among species with high interspecific distances (10%–21.2%) and low intraspecific distances (0.2%–6.7%) based on uncorrected p‐distance of the COI gene. Morphological species complex M. spermatoglomeratus consists of three species, M. spermatoglomeratus Zhang, Lu & Xie, 2018 sensu stricto, M. rijina sp. n., and M. manchu sp. n. The M. duodiverticulus complex consists of M. duodiverticulus sp. n. and M. similiduodiverticulus sp. n. The M. monodiverticulus complex consists of M. monodiverticulus Shen, Chen & Xie, 2012 sensu stricto, M. ngulen sp. n., M. zhenggulen sp. n., and M. fokulen sp. n. Further new species, distinguishable with morphological as well as molecular methods, are M. similigigachaetus sp. n., M. parvidiverticulus sp. n., M. digitalisdiverticulus sp. n., and M. infradiverticulus sp. n. Finally, we inferred the morphogenetic processes of spermathecae and sperm bundles, and filtrated some morphological characters which are useful to identify species. As the first attempt in this genus, our study provides an opportunity to discuss the currently used taxonomic criteria and acquire new ideas for the taxonomy of enchytraeids. [ABSTRACT FROM AUTHOR]

Ag-based brazing filler metals are preferred in many industries, but the high price of Ag restricts their wider application. Therefore, developing novel low-Ag brazing filler metals has aroused extensive interest. In this study, the effects of the In and Ga elements on the melting behavior and spreading property of Ag10CuZnSn filler metal and the microstructure and strength of the brazed joints were investigated. The results show that both In and Ga can significantly decrease the solidus and liquidus temperatures of the filler metal. The In element can dissolve into the liquid filler metal and the Ga element can decrease the surface tension of the melted filler metal, which, in turn, improves the spreading area. The In element prefers to dissolve into the Ag-rich phase, and the Ga element prefers to dissolve into the Cu-rich phase; both improve the strength of the filler metal through solid-solution strengthening. The shear strength of the 304 stainless-steel brazed joint reached a peak value of 396 MPa when the Ag10CuZnSn-1.5In-2Ga (wt%) filler metal was used. However, the excessive addition of In and Ga forms brittle intermetallic compounds (IMCs) in the brazing seam, which decreases the strength of the brazed joint. [ABSTRACT FROM AUTHOR]