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Elevating redox potential towards robust single-crystalline NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2) via chlorination engineering
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作者 Ziyue Qiu Shihao Li +6 位作者 Wei Zhou Fangyan Liu Yuhang Zhang Yi Zhang Huiru Wang Yanqing Lai Zhian Zhang 《Journal of Energy Chemistry》 2025年第12期867-876,I0019,共11页
The active surface chemistry of O3-type NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM) results in poor air stability,leading to severe structural degradation upon exposure to air.Elevating the redox potential of the material ca... The active surface chemistry of O3-type NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM) results in poor air stability,leading to severe structural degradation upon exposure to air.Elevating the redox potential of the material can suppress the spontaneous deintercalation of Na^(+),thereby mitigating this issue;however,the underlying strategies and mechanisms for such enhancement remain unclear.In this study,we develop a chlorination treatment approach to elevate the redox potential of the single-crystalline NFM,and the modified sample(NFM-Cl) demonstrates enhanced electrochemical performance and air stability.In NFM-Cl,partial Cl^(-)is incorporated into O sites,expanding the Na^(+) channels,and the band gap between the transition metal(TM) 3d orbitals and the Fermi level is broadened to enhance the cationic redox potential of TM ions and reduce spontaneous sodium deintercalation.Simultaneously,the surface residual alkali of NFM-Cl is in situ transformed into a chlorinated interfacial layer,serving as a physical barrier to prevent direct contact between NFM-Cl and the electrolyte or humid air.Consequently,NFM-Cl exhibits a remarkable capacity retention of 89.1 % after 200 cycles at 1 C and 82.0 % after 15 days of exposure to a simulated air environment.This study presents a novel strategy for elevating the redox potential of cathode materials for sodium-ion batteries(SIBs) and elucidates the underlying mechanism,offering an air-stable oxide cathode material with high specific energy and long cycle life,along with an advanced SIB system. 展开更多
关键词 Sodium-ion battery Single-crystalline layered oxide POST-TREATMENT Elevated redox potential Surface chemistry
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The effect of elevating temperature on the growth and development of reproductive organs and yield of summer maize 被引量:9
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作者 SHAO Rui-xin YU Kang-ke +5 位作者 LI Hong-wei JIA Shuang-jie YANG Qing-hua ZHAO Xia ZHAO Ya-li LIU Tian-xue 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第7期1783-1795,共13页
Compared to other crops,maize production demands relatively high temperatures.However,temperatures exceeding 35℃lead to adverse effects on maize yield.High temperatures(≥35℃)are consistently experienced by summer m... Compared to other crops,maize production demands relatively high temperatures.However,temperatures exceeding 35℃lead to adverse effects on maize yield.High temperatures(≥35℃)are consistently experienced by summer maize during its reproductive growth stage in the North China Plain,which is likely to cause irreversible crop damage.This study investigated the effects of elevating temperature(ET)treatment on the yield component of summer maize,beginning at the 9th unfolding leaf stage and ending at the tasseling stage.Results demonstrated that continuous ET led to a decrease in the elongation rate and activity of silks and an elongated interval between anthesis and silking stages,and eventually decreased grain number at ear tip and reduced yield.Although continuous ET before tasseling damaged the anther structure,reduced pollen activity,delayed the start of the pollen shedding stage,and shortened the pollen shedding time,it was inferred,based on phenotypical and physiological traits,that continuous ET after the 9th unfolding leaf stage influenced ears and therefore may have more significant impacts.Overall,when maize plants were exposed to ET treatment in the ear reproductive development stage,the growth of ears and tassels was blocked,which increased the occurrence of barren ear tips and led to large yield losses. 展开更多
关键词 summer maize North China Plain elevating temperatures reproductive stage barren ear tip YIELD
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Range shifts of four Larix species across a three-dimensional geographic gradient in response to climate change
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作者 Zhi Zhang Wenqiang Gao +1 位作者 Xiangdong Lei Jiejie Sun 《Journal of Forestry Research》 2026年第2期72-84,共13页
Climate warming is significantly altering the distribution of tree species,which holds crucial implications for China’s Larix species as they are important afforestation efforts.Understanding their optimal habitats a... Climate warming is significantly altering the distribution of tree species,which holds crucial implications for China’s Larix species as they are important afforestation efforts.Understanding their optimal habitats and environmental constraints is vital for predicting range shifts and guiding adaptive forest management.Previous studies prioritized changing climate impacts on horizontal range shifts of Larix,neglecting the influence of soil factors and range shift along altitudinal gradients.To address this,we applied an optimized MaxEnt model to assess current and future SSP126/SSP585 scenarios,three-dimensional habitat suitability(latitude,longitude,altitude)for four major Larix species(L.principis-rupprechtii,L.gmelinii,L.kaempferi,L.olgensis),while identifying key environmental drivers.Our results indicate that elevation and extreme moisture conditions universally constrain their distribution.Soil chemistry properties exhibited species-specific influences:cation exchange capacity critically shaped L.principis-rupprechtii and L.gmelinii ranges,whereas exchangeable aluminum determined L.kaempferi and L.olgensis distribution.Under future climate scenarios,habitat areas show divergent trajectories-L.principis-rupprechtii maximum gains 5.1%under SSP126,while L.kaempferi maximum expands 15.1%.Conversely,SSP585 triggered a 3.7% decline for L.gmelinii during the 2040s−2100s,and L.olgensis faces a net reduction to 0.4% by 2100s despite transient gains.Spatially,three species(L.kaempferi,L.gmelinii,L.olgensis)shifted northward,while L.principis-rupprechtii migrated northwest.All species distribution ascended altitudinally reflecting thermal adaptation strategies.These multidimensional insights enable targeted species selection for climate-resilient afforestation and underscore the need for soil-inclusive management planning. 展开更多
关键词 Climate change MaxEnt model ELEVATION Cation exchange capacity Exchangeable aluminum
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Environmental controls over calcium and magnesium concentrations in the forest floor and topsoil in the Loess Plateau,China
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作者 Feng Xue Ning Pan +9 位作者 Hongkun Cui Aolin Li Mingfei Zhao Kaixiong Xing Yuhang Wang Xuejuan Bai Can Wang Zhijun Yu Jingze Liu Muyi Kang 《Journal of Forestry Research》 2026年第2期201-212,共12页
The dynamics of calcium(Ca)and magnesium(Mg)in the forest floor and topsoil caused by anthropogenic and natural processes continue to be a concern in temperate forests.However,the impacts of abiotic and biotic variabl... The dynamics of calcium(Ca)and magnesium(Mg)in the forest floor and topsoil caused by anthropogenic and natural processes continue to be a concern in temperate forests.However,the impacts of abiotic and biotic variables as well as their interactions remain unclear,especially in areas undergoing long-term forest restoration.In this study,Ca and Mg concentrations in the forest floor and topsoil from 239 forest plots across the Loess Plateau were measured,and the effects of forest types,climate,soil properties,stand characteristics and nitrogen deposition were explored.The results showed significantly higher Ca concentrations in the forest floor(20.68±8.04 mg/g)than in the topsoil(13.28±12.83 mg/g),whereas Mg exhibited the inverse pattern(3.64±1.09 and 10.11±2.51 mg/g,respectively).The effect of forest types was only significant on forest floor Ca,and Ca concentrations were higher in broadleaf and mixed forests than in coniferous forests.Overall,Ca and Mg concentrations in forest floor and topsoil increased with latitudes while decreased with elevations,and the significance of the trends varied among forest types.Forest floor Ca and Mg were mainly influenced by environmental variables aboveground,i.e.,basal area(BA)and mean annual precipitation(MAP),respectively;topsoil Ca and Mg were more affected by soil properties(soil C/N and pH,respectively).Those suggested a depletion of Ca belowground was associated with forest growth and enriched soil nitrogen,and the leaching of mobile Mg was correlated with rainfall and soil acidification.Besides,the impact of environmental variables on Ca-Mg balance(Ca/Mg ratio)belowground was primarily through the regulation of Ca.Elucidating the influence of environmental variables will improve our ability to predict future changes in base cations and thus forest soil health in the greening vegetated Loess Plateau. 展开更多
关键词 Soil C/N Basal area Random-forest model Temperate forests Base cations ELEVATION
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Unraveling the invasion patterns of Galinsoga quadriradiata in mountain ranges:Insights from human activities,phenotypic and genetic variations
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作者 Yu Chen Xingjiang Song +5 位作者 Gang Liu Jia Wang Chunling Zhang Xiaojian Chang Jiabin Zou Zhihong Zhu 《Plant Diversity》 2026年第1期192-203,共12页
Prevention of biological invasion requires understanding how alien species invade native communities.Although studies have identified mechanisms that underlie plant invasion in some habitats,limited attention has focu... Prevention of biological invasion requires understanding how alien species invade native communities.Although studies have identified mechanisms that underlie plant invasion in some habitats,limited attention has focused on invasion patterns along elevational gradients.In this study,we asked which factors drive the global and regional distribution of the invasive plant Galinsoga quadriradiata along elevational gradients.To answer this question,we examined whether human activities(i.e.,roads)promote G.quadriradiata invasion,how seed dispersal-related traits of G.quadriradiata change along elevation gradients,and whether G.quadriradiata has adapted to high-elevation environments through phenotypic plasticity or genetic variation.On the global scale,we found that human activities and road density positively contribute to the G.quadriradiata expansion in mountainous areas.Field surveys in China revealed significant elevational differences in the seed dispersal traits of G.quadriradiata,with higher-elevation populations exhibiting lower dispersal ability and generally lower genetic diversity.Under common conditions,high-elevation populations showed higher leaf mass ratio but lower root mass ratio and reproductive allocation.This suggests that high-elevation environments create a barrier to dispersal for G.quadriradiata,and that G.quadriradiata has adapted phenotypically to these conditions.Our study indicates that the elevational invasion pattern of G.quadriradiata is shaped by multiple factors,particularly human activities and phenotypic adaptability.In addition,our finding that G.quadriradiata invasion at high elevations is not constrained by low genetic diversity indicates that monitoring and management of G.quadriradiata in mountainous areas should be strengthened. 展开更多
关键词 Invasive plants Phenotypic plasticity Seed dispersal ability Genetic variation Human activities Elevational gradient
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Increasing Elevation Reduces Complexity of Soil Microbial Co-occurring Network in Changbai Mountains,China
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作者 LIU Xue WU Haitao +4 位作者 GUAN Qiang LU Kangle LIU Dandan KANG Yujuan ZHANG Shixiu 《Chinese Geographical Science》 2026年第2期306-319,I0004-I0006,共17页
Elevation patterns and assembly processes of soil microbial community structures are essential for understanding biogeo-chemical processes in mountain systems.Differences in soil properties caused by elevation gradien... Elevation patterns and assembly processes of soil microbial community structures are essential for understanding biogeo-chemical processes in mountain systems.Differences in soil properties caused by elevation gradients can regulate the spatial distribu-tion and network complexity of the community structure.To explore the variations in soil microbial community structures and their as-sembly mechanisms across different elevations of the Changbai Mountains,as well as their responses to environmental factors,we col-lected microbial samples along an elevational gradient(seven elevations containing four vegetation zones)on the western slope of the Changbai Mountains using the method of metagenomic sequencing.The results showed a significant difference(P<0.05)for the Chao1 index across different elevations,but no significant difference was observed for the Shannon and Simpson indices.With increasing elev-ation,the number of nodes and links in the microbial network gradually decreased.Acidobacteria were highly connected to many nodes.The microbial communities indicated a significant distance-decay relationship(P<0.001)and were affected more by stochastic pro-cesses along the elevation gradient.The results of the Structural Equation Model(SEM)showed that elevation had direct significant ef-fect on carbon(C,P<0.01),nitrogen(N,P<0.01),and phosphorus(P,P<0.05)and weak negative effect on their ecological stoi-chiometry.Elevation was one of the major variables contributing to microbial network topology.The contribution of C and N to micro-bial network complexity was higher than that of P.Our study provides valuable insights into the responses of soil microbial communit-ies to elevation variations. 展开更多
关键词 assembly processes co-occurring network elevation gradient microbial community soil nutrient Changbai Mountains China
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Unlocking the potential of DULL NITROGEN RESPONSE 1 for climate-smart crop breeding under elevated CO_(2)
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作者 Muhammad Imran Ming Xu 《Journal of Integrative Plant Biology》 2026年第1期9-12,共4页
Increasing atmospheric CO_(2)concentrations from~280 ppm in the pre-industrial era to over 420 ppm today, and projected to exceed 550 ppm by 2050(IPCC, 2023), are transforming the biochemical context of plant metaboli... Increasing atmospheric CO_(2)concentrations from~280 ppm in the pre-industrial era to over 420 ppm today, and projected to exceed 550 ppm by 2050(IPCC, 2023), are transforming the biochemical context of plant metabolism,causing restructuring of carbon and nitrogen balance in crops. Though elevated CO_(2)(eCO_(2)) increases photosynthetic efficacy and biomass accumulation in many C3crops, it also disrupts carbon-nitrogen balance, leading to nitrogen dilution in leaves and grains, eventually compromising food quality(Myers et al., 2014;Rezaei et al., 2023). Rice is a staple food that feeds nearly half of the world's population;it requires sustained yield gains, considering an estimated 35%-56%increase in demand by 2050, as the global population approaches 10 billion(Van Dijk et al., 2021), while reducing dependency on nitrogen fertilizers, whose production and overuse contribute significantly to greenhouse gas emission(Qian et al., 2023). Yet, most breeding programs remain regulated to present-day atmospheric conditions, overlooking the physiological and molecular adaptations required for future CO_(2)climates. 展开更多
关键词 carbon nitrogen balance food q rice nitrogen response elevated CO food quality photosynthetic efficacy climate smart crop breeding
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Unsupervised subdomain contrastive adaptation for elevator fault diagnosis based on time-frequency feature attention mechanism segmentation
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作者 Chenyu FENG Hao SUN +6 位作者 Pengcheng XIA Chengjin QIN Zhinan ZHANG Cheng HE Bin ZHENG Jiacheng JIANG Chengliang LIU 《Science China(Technological Sciences)》 2026年第2期302-323,共22页
Existing elevator fault diagnosis algorithms have limited engineering applicability due to variations in working conditions and differences in equipment structures.To address this limitation,this study proposes an uns... Existing elevator fault diagnosis algorithms have limited engineering applicability due to variations in working conditions and differences in equipment structures.To address this limitation,this study proposes an unsupervised subdomain adaptation method based on a time-frequency feature attention mechanism,LMMD-based subdomain alignment,and contrastive local alignment.This enables the application of the diagnosis model across different working conditions and equipment types.First,a novel time-frequency feature attention mechanism assigns weights to vibration signals of varying dimensions.Second,the time series is transformed to obtain a three-channel time-frequency diagram.This diagram is input into the proposed dimension-segmentation cross-channel multihead self-attention framework to extract high-dimensional frequencydomain fault features.These features are concatenated with the time-domain features to obtain a global feature representation.Then,the extracted high-dimensional features are sent to the classification module to obtain the predicted labels for the source and target domains.Finally,after confidence filtering,the true labels from the source domain and the prediction labels from the target domain are fed into a dynamically weighted multilevel feature alignment module to promote proximity between similar fault features across domains while enhancing separation among different fault types.The validity and superiority of the proposed method were demonstrated through simulation experiments conducted on two types of manned escalator systems under multiple working conditions.For the most challenging transfer task,the proposed method achieved higher accuracy on the target domain test set than DANN,ADDA,C-CLCN,TFA-CCN,and TFA-LCN by 26.87%,24.72%,11.44%,28.94%,and 16.85%,respectively. 展开更多
关键词 time-frequency feature attention mechanism unsupervised domain adaptation fault diagnosis transfer learning passenger elevator
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Diurnal Bias Correction of FY-4B AGRI Water Vapor Channels with Time-Shifted Solar Elevation Angle
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作者 SONG Jia-yun HAN Wei +1 位作者 SUN Hao-fei YANG Yun-fan 《Journal of Tropical Meteorology》 2026年第1期19-32,共14页
The infrared channels of the FY-4B advanced geosynchronous radiation imagers(AGRI) play a crucial role in temperature and humidity analyses for mesoscale numerical weather prediction, particularly in enhancing the ini... The infrared channels of the FY-4B advanced geosynchronous radiation imagers(AGRI) play a crucial role in temperature and humidity analyses for mesoscale numerical weather prediction, particularly in enhancing the initial field quality and the forecasting accuracy of the model. This study assimilated FY-4B AGRI data into the CMA-MESO model and analyzed the bias characteristics and correction methods. Analysis of the AGRI data revealed a clear diurnal variation in the bias, which was positively correlated with the solar elevation angle. However, the diurnal variation in the bias lagged behind the solar elevation angle, likely owing to temperature changes and delayed instrument responses resulting from solar radiation. To address this issue, we propose a correction method that utilizes the solar elevation angle after an optimal time shift. Using the time-shifted solar elevation angle as a predictor effectively reduces the diurnal variation in bias and significantly improves the correction effect. This approach provides theoretical support for the assimilation of FY-4B AGRI data into mesoscale numerical weather predictions, thereby enhancing the reliability of the assimilation results. 展开更多
关键词 FY-4B AGRI bias correction diurnal variation solar elevation angle
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A Dual-Stream Framework for Landslide Segmentation with Cross-Attention Enhancement and Gated Multimodal Fusion
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作者 Md Minhazul Islam Yunfei Yin +2 位作者 Md Tanvir Islam Zheng Yuan Argho Dey 《Computers, Materials & Continua》 2026年第3期285-304,共20页
Automatic segmentation of landslides from remote sensing imagery is challenging because traditional machine learning and early CNN-based models often fail to generalize across heterogeneous landscapes,where segmentati... Automatic segmentation of landslides from remote sensing imagery is challenging because traditional machine learning and early CNN-based models often fail to generalize across heterogeneous landscapes,where segmentation maps contain sparse and fragmented landslide regions under diverse geographical conditions.To address these issues,we propose a lightweight dual-stream siamese deep learning framework that integrates optical and topographical data fusion with an adaptive decoder,guided multimodal fusion,and deep supervision.The framework is built upon the synergistic combination of cross-attention,gated fusion,and sub-pixel upsampling within a unified dual-stream architecture specifically optimized for landslide segmentation,enabling efficient context modeling and robust feature exchange between modalities.The decoder captures long-range context at deeper levels using lightweight cross-attention and refines spatial details at shallower levels through attention-gated skip fusion,enabling precise boundary delineation and fewer false positives.The gated fusion further enhances multimodal integration of optical and topographical cues,and the deep supervision stabilizes training and improves generalization.Moreover,to mitigate checkerboard artifacts,a learnable sub-pixel upsampling is devised to replace the traditional transposed convolution.Despite its compact design with fewer parameters,the model consistently outperforms state-of-the-art baselines.Experiments on two benchmark datasets,Landslide4Sense and Bijie,confirm the effectiveness of the framework.On the Bijie dataset,it achieves an F1-score of 0.9110 and an intersection over union(IoU)of 0.8839.These results highlight its potential for accurate large-scale landslide inventory mapping and real-time disaster response.The implementation is publicly available at https://github.com/mishaown/DiGATe-UNet-LandSlide-Segmentation(accessed on 3 November 2025). 展开更多
关键词 Landslide segmentation remote sensing dual-stream lightweight networks digital elevation model(DEM) gated fusion
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Elevating kinetics of passivated Fe anodes with NH_(4)Cl regulator:Toward low-cost,long-cyclic and green cathode-free Fe-ion aqueous batteries 被引量:1
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作者 Shibo Chai Jianhui Zhu +1 位作者 Jian Jiang Chang Ming Li 《Nano Research》 SCIE EI CSCD 2022年第4期3187-3194,共8页
The environment benignity and battery cost are major concerns for grid-scale energy storage applications.The emerging dendrite-free Fe-ion aqueous batteries are promising due to the rich natural abundance,low cost and... The environment benignity and battery cost are major concerns for grid-scale energy storage applications.The emerging dendrite-free Fe-ion aqueous batteries are promising due to the rich natural abundance,low cost and non-toxicity for Fe resources.However,serious passivation reactions on Fe anodes and poor long-term cyclability for matched cathodes still stand in the way for their practical usage.To settle above constraints,we herein use NH_(4)Cl as the electrolyte regulator to elevate the reaction kinetics of passivated Fe anodes,and also propose a special cathode-free design to prolong the cells lifetime over 1,000 cycles.The added NH_(4)Cl can erode/break inert passivation layers and strengthen the ion conductivity of electrolytes,facilitating the reversible Fe plating/stripping and Fe^(2+)shuttling.The highly puffed nano carbon foams function as current collectors and actives anchoring hosts,enabling expedite Fe^(2+)adsorption/desorption,FeII/FeIII redox conversions and FeIII deposition.The configured rocking-chair Fe-ion cells have good environmental benignity and decent energy-storage behaviors,including high reactivity/reversibility,outstanding cyclic stability and far enhanced operation longevity.Such economical,long-cyclic and green cathode-free Fe-ion batteries may hold great potential in near-future energy-storage power stations. 展开更多
关键词 elevated kinetics passivated Fe anodes NH_(4)Cl regulator cathode-free design Fe-ion batteries
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Seasonal variation in habitat preference of the Himalayan monal(Lophophorus impejanus)in Langtang National Park,Nepal:Implications for conservation 被引量:1
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作者 Birat Raj Rajak Laxman Khanal +4 位作者 Asmit Subba Amrit Nepali Sandip Kumar Gupta Hem Sagar Baral Randall C.Kyes 《Zoological Research(Diversity and Conservation)》 2025年第1期32-41,共10页
The Himalayan monal(Lophophorus impejanus),Nepal’s national bird,is a protected species facing significant conservation challenges.Understanding the distribution and habitat preferences of the Himalayan monal(HM)is c... The Himalayan monal(Lophophorus impejanus),Nepal’s national bird,is a protected species facing significant conservation challenges.Understanding the distribution and habitat preferences of the Himalayan monal(HM)is crucial for its conservation.This study was conducted in the Langtang National Park(LNP),Nepal using the route census method during both winter(November/December 2022)and summer(June 2023)seasons to examine the seasonal variation in HM’s elevational distribution and habitat preference.Further,we assessed their conservation threats by conducting a semi-structured questionnaire survey with the local residents.During the winter period,the HMs preferred grassland habitats,while in the summer,their preference shifted to shrubland and barren area.HM abundance was negatively associated with the Normalized Differential Vegetation Index(NDVI)and the shortest distance from the survey trails in the winter.The HMs actively avoided areas with high anthropogenic pressure.In the summer,they showed a wider elevational range up to 4400 m above sea level(a.s.l.),with a higher sighting frequency between 3600 and 3900 m a.s.l.The questionnaire survey of the local residents revealed that anthropogenic pressure such as poaching and free-ranging livestock grazing are the major threats to the species in the study area.This study provides valuable insight into the complex habitat preferences and critical threats faced by the HMs in LNP and underscores the urgent need for targeted conservation action. 展开更多
关键词 PHEASANTS National bird Conservation threats Seasonal habitats Elevational distribution
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Dual heterogeneous structure enabled ultrahigh strength and ductility across a broad temperature range in CrCoNi-based medium-entropy alloy 被引量:1
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作者 Kang Tu Bo Li +2 位作者 Zonglin Li Kaisheng Ming Shijian Zheng 《Journal of Materials Science & Technology》 2025年第4期46-59,共14页
Developing alloys with exceptional strength-ductility combinations across a broad temperature range is crucial for advanced structural applications.The emerging face-centered cubic medium-entropy alloys(MEAs)demonstra... Developing alloys with exceptional strength-ductility combinations across a broad temperature range is crucial for advanced structural applications.The emerging face-centered cubic medium-entropy alloys(MEAs)demonstrate outstanding mechanical properties at both ambient and cryogenic temperatures.They are anticipated to extend their applicability to elevated temperatures,owing to their inherent advantages in leveraging multiple strengthening and deformation mechanisms.Here,a dual heterostructure,comprising of heterogeneous grain structure with heterogeneous distribution of the micro-scale Nb-rich Laves phases,is introduced in a CrCoNi-based MEA through thermo-mechanical processing.Additionally,a high-density nano-coherentγ’phase is introduced within the grains through isothermal aging treatments.The superior thermal stability of the heterogeneously distributed precipitates enables the dual heterostructure to persist at temperatures up to 1073 K,allowing the MEA to maintain excellent mechanical properties across a wide temperature range.The yield strength of the dual-heterogeneous-structured MEA reaches up to 1.2 GPa,1.1 GPa,0.8 GPa,and 0.6 GPa,coupled with total elongation values of 28.6%,28.4%,12.6%,and 6.1%at 93 K,298 K,873 K,and 1073 K,respectively.The high yield strength primar-ily stems from precipitation strengthening and hetero-deformation-induced strengthening.The high flow stress and low stacking fault energy of the dual-heterogeneous-structured MEA promote the formation of high-density stacking faults and nanotwins during deformation from 93 K to 1073 K,and their density increase with decreasing deformation temperature.This greatly contributes to the enhanced strainhardening capability and ductility across a wide temperature range.This study offers a practical solution for designing dual-heterogeneous-structured MEAs with both high yield strength and large ductility across a wide temperature range. 展开更多
关键词 Medium-entropy alloy Dual heterogeneous structure Strength-ductility synergy Cryogenic temperatures Elevated temperatures
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Equation of State of a Fluid H_(2)O-CO_(2) at Temperatures 50–350 °C and Pressures 0.2–3.5 kbar 被引量:1
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作者 Mikhail V.Ivanov 《Journal of Environmental & Earth Sciences》 2025年第1期625-631,共7页
An equation of state(EOS)was obtained that accurately describes the thermodynamics of the system H_(2)O–CO_(2) at temperatures of 50–350°C and pressures of 0.2–3.5 kbar.The equation is based on experimental da... An equation of state(EOS)was obtained that accurately describes the thermodynamics of the system H_(2)O–CO_(2) at temperatures of 50–350°C and pressures of 0.2–3.5 kbar.The equation is based on experimental data on the compositions of the coexisting liquid and gas phases and the Van Laar model,within which the values of the Van Laar parameters A12 and A21 were found for each experimental P-T point.For the resulting sets A12(P,T),A21(P,T),approximation formulas describing the dependences of these quantities on temperature and pressure were found and the parameters contained in the formulas were fitted.This two-stage approach made it possible to obtain an adequate thermodynamic description of the system,which allows,in addition to determining the phase state of the system(homogeneous or heterogeneous),to calculate the excess free energy of mixing of H_(2)O and CO_(2),the activities of H_(2)O and CO_(2),and other thermodynamic characteristics of the system.The possibility of such calculations creates the basis for using the obtained EOS in thermodynamic models of more complicated fluid systems in P-T conditions of the middle and upper crust.These fluids play an important role in many geological processes including the transport of ore matter and forming hydrothermal ore deposits,in particular,the most of the world’s gold deposits.The knowledge of thermodynamics of these fluids is important in the technology of drilling oil and gas wells.In particular,this concerns the prevention of precipitation of solid salts in the well. 展开更多
关键词 High Pressure Elevated Temperature Water-Carbon Dioxide Fluid Equation of State
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Insights into room-and elevated-temperature micro-mechanisms of laser shock peened M50 steel with superior tribological performance 被引量:1
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作者 Zhenyang Cao Luqing Cui +6 位作者 Sihai Luo Jingdong Song Hao Su Zhicong Pang Wang Zhao Weifeng He Xiaoqing Liang 《Journal of Materials Science & Technology》 2025年第2期270-285,共16页
M50 steel,commonly utilized in aircraft engine bearings,is susceptible to friction-induced failures,particularly in high-temperature service conditions.To address this issue,various strategies have been proposed,with ... M50 steel,commonly utilized in aircraft engine bearings,is susceptible to friction-induced failures,particularly in high-temperature service conditions.To address this issue,various strategies have been proposed,with laser shock peening(LSP)garnering significant attention due to its deeper residual stress penetration and excellent surface integrity,whereas the underlying strengthening mechanisms have not yet been fully elucidated.In this study,we systematically investigate the impact of LSP treatment on the tribological properties of M50 steel at temperatures of 25 and 300℃,alongside elucidating the relevant micro-mechanisms.Microstructural analysis reveals that laser impact strengthening primarily arises from dislocation proliferation,resulting in a surface hardness increase of approximately 14%and the formation of a substantial compressive stress layer reaching a maximum value of about 1200 MPa,with a depth of around 2 mm.Friction test results demonstrate reduced coefficients of friction and wear rates following LSP treatment at both temperatures.Notably,a more pronounced reduction is observed at 300℃,with values decreasing by 41.4%and 55.8%,respectively.The enhanced performance is attributed to the synergistic interplay of compressive residual stresses,work-hardening layers,increased density of dislocations,and substantial microstructure refinement. 展开更多
关键词 M50 bearing steel Laser shock peening Tribological performance Elevated temperatures Compressive residual stress
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Using higher cut-off values to diagnose acute myocardial infarction in patients with elevated hs-cTnT 被引量:1
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作者 Tian Wu Jiaqi Chai +17 位作者 Chunyue Tan Zhiwen Tao Hui Yong Zhenyu Lin Xiaoxuan Gong Kun Liu Lei Xu Qin Wang Shenqi Jing Jiani Xu Hui Zhou Tao Li Liang Yuan Bo Chen Fang Wang Ruxing Wang Yun Liu Chunjian Li 《Journal of Biomedical Research》 2025年第6期564-573,I0003-I0005,共13页
It is often challenging to diagnose acute myocardial infarction(AMI)in patients with elevated high-sensitivity cardiac troponin T(hs-cTnT)before observing a significant rise and/or fall in hs-cTnT.The current study ai... It is often challenging to diagnose acute myocardial infarction(AMI)in patients with elevated high-sensitivity cardiac troponin T(hs-cTnT)before observing a significant rise and/or fall in hs-cTnT.The current study aimed to identify an optimal cut-off to rule in AMI.A total of 76411 patients with elevated hs-cTnT were included.The predictive cut-off values for diagnosing ST-segment elevation myocardial infarction(STEMI)and non-STsegment elevation myocardial infarction(NSTEMI)were assessed using the area under the receiver operating characteristic curve(AUC).Among the patients,50466(66.0%)had non-cardiac diseases,25945(34.0%)had cardiac diseases,and 15502(20.3%)had AMI,including 816(1.1%)with STEMI and 14686(19.2%)with NSTEMI.The median hs-cTnT level was 3788.0 ng/L in STEMI patients and 67.2 ng/L in NSTEMI patients.The optimal cut-off for diagnosing STEMI was 251.9 ng/L,with a sensitivity of 90.7%,specificity of 86.5%,and an AUC of 0.942;the optimal cut-off for diagnosing NSTEMI was 130.5 ng/L,with a sensitivity of 40.9%,specificity of 83.8%,and an AUC of 0.638.Collectively,optimizing the cut-off values for diagnosing STEMI and NSTEMI to 251.9 ng/L and 130.5 ng/L,respectively,demonstrated high accuracy in a large cohort of Chinese patients with elevated hs-cTnT. 展开更多
关键词 acute myocardial infarction high sensitivity cardiac troponin T ELECTROCARDIOGRAM ST-segment elevation myocardial infarction renal dysfunction
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Mechanisms behind elevated serum levels of plasminogen activator inhibitor-1 in frontotemporal lobar degeneration
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作者 Francesco Angelucci Jakub Hort 《Neural Regeneration Research》 SCIE CAS 2025年第8期2317-2318,共2页
Frontotemporal lobar degeneration(FTLD)is a form of progressive dementia characterized by degeneration of the frontal and temporal lobes of the brain.This pathology involves a series of cognitive,behavioral,and neurol... Frontotemporal lobar degeneration(FTLD)is a form of progressive dementia characterized by degeneration of the frontal and temporal lobes of the brain.This pathology involves a series of cognitive,behavioral,and neurological symptoms that influence personality,decision-making ability,and language. 展开更多
关键词 DEGENERATION ELEVATED PATHOLOGY
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Successful emergency surgical intervention in acute non-STsegment elevation myocardial infarction with rupture:A case report
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作者 Xing-Po Li Zi-Shan Wang +1 位作者 Hong-Xia Yu Shan-Shan Wang 《World Journal of Clinical Cases》 SCIE 2025年第4期41-47,共7页
BACKGROUND The incidence of acute myocardial infarction(AMI)is rising,with cardiac rupture accounting for approximately 2%of deaths in patients with acute ST-segment elevation myocardial infarction(STEMI).Ventricular ... BACKGROUND The incidence of acute myocardial infarction(AMI)is rising,with cardiac rupture accounting for approximately 2%of deaths in patients with acute ST-segment elevation myocardial infarction(STEMI).Ventricular free wall rupture(FWR)occurs in approximately 2%of AMI patients and is notably rare in patients with non-STEMI.Types of cardiac rupture include left ventricular FWR,ventricular septal rupture,and papillary muscle rupture.The FWR usually leads to acute cardiac tamponade or electromechanical dissociation,where standard resuscitation efforts may not be effective.Ventricular septal rupture and papillary muscle rupture often result in refractory heart failure,with mortality rates over 50%,even with surgical or percutaneous repair options.CASE SUMMARY We present a rare case of an acute non-STEMI patient who suffered sudden FWR causing cardiac tamponade and loss of consciousness immediate before undergoing coronary angiography.Prompt resuscitation and emergency open-heart repair along with coronary artery bypass grafting resulted in successful patient recovery.CONCLUSION This case emphasizes the risks of AMI complications,shares a successful treatment scenario,and discusses measures to prevent such complications. 展开更多
关键词 Acute non-ST segment elevation myocardial infarction Cardiac rupture Acute myocardial infarction Free wall rupture Case report
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Global change factors cause decoupling of nutrient dynamics and asynchrony between microbial communities and ecological functions in a temperate grassland soil
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作者 Yuqian LI Junwei MA +2 位作者 Yijia LI Xinyi SHEN Xinghui XIA 《Pedosphere》 2025年第4期627-640,共14页
Soil microbial communities and grassland ecosystem processes are increasingly confronted with multiple global change factors(GCFs).There is still a lack of research on how these multiple GCFs interact and impact soil ... Soil microbial communities and grassland ecosystem processes are increasingly confronted with multiple global change factors(GCFs).There is still a lack of research on how these multiple GCFs interact and impact soil microbial communities and their functions.To address this gap,we conducted a simulation experiment to examine the individual and interactive effects of the four most critical and prevalent GCFs,elevated carbon dioxide concentration(eCO_(2)),elevated temperature(eT),decreased precipitation(dP),and elevated nitrogen(N)deposition(eN).This study focused on their effects on soil physicochemical properties,bacterial and fungal communities,and extracellular enzyme activities(EEAs)related to carbon(C),N,and phosphorus(P)cycles in a temperate grassland.Results showed that eCO_(2),eN,and dP tended to increase EEAs,while having neutral effects on microbial diversity and community composition.On the other hand,eT resulted in decreases in soil pH,total C,total N,EEAs,and microbial diversity,but increases in plant biomass,total P,microbial richness,and network complexity and stability.This shift in the nutrient limitation from P to N under warming conditions resulted in decoupling of nutrients.Neutral or slightly negative relationships were found between enzyme activities and microbial richness,diversity,and dominant species,and the responses of microbial communities and ecological functions were asynchronous under GCFs.Importantly,our results revealed significant higher-order interactions among GCFs and found that they had notable effects on soil physicochemical properties as well as on microbial communities and ecological functions.These findings provide valuable insights and suggestions for ecological adaptations to future global changes. 展开更多
关键词 decreased precipitation elevated carbon dioxide concentration elevated nitrogen deposition elevated temperature higher-order interaction soil enzymes soil microbiota soil nutrients
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