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971.
Sodium Ion Stabilized Vanadium Oxide Nanowire Cathode for High‐Performance Zinc‐Ion Batteries 下载免费PDF全文
Pan He Guobin Zhang Xiaobin Liao Mengyu Yan Xu Xu Qinyou An Jun Liu Liqiang Mai 《Liver Transplantation》2018,8(10)
Aqueous Zn‐ion batteries (ZIBs) have received incremental attention because of their cost‐effectiveness and the materials abundance. They are a promising choice for large‐scale energy storage applications. However, developing suitable cathode materials for ZIBs remains a great challenge. In this work, pioneering work on the designing and construction of aqueous Zn//Na0.33V2O5 batteries is reported. The Na0.33V2O5 (NVO) electrode delivers a high capacity of 367.1 mA h g?1 at 0.1 A g?1, and exhibits long‐term cyclic stability with a capacity retention over 93% for 1000 cycles. The improvement of electrical conductivity, resulting from the intercalation of sodium ions between the [V4O12]n layers, is demonstrated by single nanowire device. Furthermore, the reversible intercalation reaction mechanism is confirmed by X‐ray diffraction, Raman, X‐ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy analysis. The outstanding performance can be attributed to the stable layered structure and high conductivity of NVO. This work also indicates that layered structural materials show great potential as the cathode of ZIBs, and the indigenous ions can act as pillars to stabilize the layered structure, thereby ensuring an enhanced cycling stability. 相似文献
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Aim
Many important patterns and processes vary across the phylogeny and depend on phylogenetic scale. Nonetheless, phylogenetic scale has never been formally conceptualized, and its potential remains largely unexplored. Here, we formalize the concept of phylogenetic scale, review how phylogenetic scale has been considered across multiple fields and provide practical guidelines for the use of phylogenetic scale to address a range of biological questions.Innovation
We summarize how phylogenetic scale has been treated in macroevolution, community ecology, biogeography and macroecology, illustrating how it can inform, and possibly resolve, some of the longstanding controversies in these fields. To promote the concept empirically, we define phylogenetic grain and extent, scale dependence, scaling and the domains of phylogenetic scale. We illustrate how existing phylogenetic data and statistical tools can be used to investigate the effects of scale on a variety of well‐known patterns and processes, including diversification rates, community structure, niche conservatism or species‐abundance distributions.Main conclusions
Explicit consideration of phylogenetic scale can provide new and more complete insight into many longstanding questions across multiple fields (macroevolution, community ecology, biogeography and macroecology). Building on the existing resources and isolated efforts across fields, future research centred on phylogenetic scale might enrich our understanding of the processes that together, but over different scales, shape the diversity of life. 相似文献976.
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Factors influencing above‐ground and soil seed bank vegetation diversity at different scales in a quasi‐Mediterranean ecosystem 下载免费PDF全文
Matthew P. Chick Craig R. Nitschke Janet S. Cohn Trent D. Penman Alan York 《植被学杂志》2018,29(4):684-694
Questions
Are factors influencing plant diversity in a fire‐prone Mediterranean ecosystem of southeast Australia scale‐dependent?Location
Heathy woodland, Otways region, Victoria, southeast AustraliaMethods
We measured patterns of above‐ground and soil seed bank vegetation diversity and associated them with climatic, biotic, edaphic, topographic, spatial and disturbance factors at multiple scales (macro to micro) using linear mixed effect and generalized dissimilarity modelling.Results
At the macro‐scale, we found species richness above‐ground best described by climatic factors and in the soil seed bank by disturbance factors. At the micro‐scale we found species richness best described above‐ground and in the soil seed bank by disturbance factors, in particular time‐since‐last‐fire. We found variance in macro‐scale β‐diversity (species turnover) best explained above‐ground by climatic and disturbance factors and in the soil seed bank by climatic and biotic factors.Conclusions
Regional climatic gradients interact with edaphic factors and fire disturbance history at small spatial scales to influence species richness and turnover in the studied ecosystem. Current fire management regimes need to incorporate key climatic–disturbance–diversity interactions to maintain floristic diversity in the studied system.979.
Sébastien Rapinel Pauline Dusseux Jan-Bernard Bouzillé Anne Bonis Arnault Lalanne Laurence Hubert-Moy 《Plant biosystems》2018,152(5):1101-1108
Geosynphytosociology deals with the study of combinations of vegetation series – or geosigmeta – within landscape. Its main advantage is to assess conservation status based on vegetation dynamics. However, this field-based approach has not been widely applied, because local surveys are not representative of spatio-temporal landscape complexity, which leads to uncertainties and errors for geosigmeta structural and functional mapping. In this context, satellite time series appear as relevant data for monitoring vegetation dynamics. This article aims to assess the contribution of an annual satellite time series for geosigmeta structural and functional mapping. The study area, which focuses on the French Atlantic coast (4630 km²), includes salt, brackish, sub-brackish and fresh marshes. A structural vegetation map was derived from the classification of an annual time series of 38 MODIS images validated with field surveys. The functional vegetation map was derived from the annual Integral of Normalized Difference Vegetation Index (NDVI-I), as an indicator of above-ground net primary production. Results show that geosigmeta were successfully mapped at a scale of 1:250,000 with an overall accuracy of 82.9%. The geosigmeta functional map highlights a strong gradient from the lowest NDVI-I values in salt marshes to the highest values in fresh marshes. 相似文献
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John A. Stanturf Palle Madsen Khosro Sagheb-Talebi Ole K. Hansen 《Plant biosystems》2018,152(3):536-546
Restoring the estimated 1 billion hectares of degraded forests must consider future climate accompanied by novel ecosystems. Transformational restoration can play a key role in adaptation to climate change but it is conceptually the most divergent from contemporary approaches favoring native species and natural disturbance regimes. Here, we review concepts of novelty in ecosystems with examples of emergent/neo-native and designed novel ecosystems, with application to transformational restoration. Danish forests have a high degree of novelty and provide a realistic context for discussing assisted migration, one method of transformational adaptation. Deforestation and impacts of past land use created a highly degraded landscape dominated by heathland in western Denmark. Restoration with non-native species began 150 years ago because the native broadleaves could not establish on the heathlands. Danish forestry continues to rely extensively on non-native species. Preparing for transformational adaptation requires risky research today to prepare for events in the future and refugia from the last glaciation may provide genetic material better adapted to future climate. A new project will test whether species and provenances from the Caspian forests in Iran possess greater genetic diversity and superior resistance (physiological adaptability) and resilience (evolutionary adaptability) and possibly a gene pool for future adaptation. 相似文献