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Interspecific Transition Among Caragana microphylla, C. davazamcii and C. korshinskii Along Geographic Gradient. Ⅰ. Ecological and RAPD Evidence 认领 引用 被引量：28
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作者 马成仓 高玉葆 +2 位作者 刘惠芬 王金龙 郭宏宇 《Acta Botanica Sinica》 2003年第10期1218-1227,共10页
The former plant population survey has shown that three genetically-related species, Caraganamicrophylla Lam., C. davazamcii Sancz. and C. korshinskii Kom., form a geographical replacement series inNei Mongol Plateau.... The former plant population survey has shown that three genetically-related species, Caraganamicrophylla Lam., C. davazamcii Sancz. and C. korshinskii Kom., form a geographical replacement series inNei Mongol Plateau. The present study on population distribution, taxonomy, morphology, development andgenetic structure demonstrated that the geographical distribution of these three species was successiveand in gradual change, thus forming a geographical cline which extended from the east to the west of NeiMongol Plateau. With an analysis of climate change over time, it was considered that the formation of thisgeographical cline was a result of plant adaptation to its natural environment. 展开更多
关键词 Caragana microphylla C. davazamcii C. korshinskii interspecific transition alonggeographical gradient Morphology Taxonomy RAPD
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Achieving serrated grain boundaries within gradient microstructures of nickel-based superalloys for dual-property turbine disks in aeroengines 认领 引用 被引量：1
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作者 Bingchao XIE Yongquan NING +4 位作者 Youwei LUO Zhaotian WANG Bowen SHI Mei ZHAN Mingwang FU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第2期641-660,共20页
Gradient microstructures strengthened by serrated Grain Boundaries(GBs)were achieved through a combination of Gradient Strain Deformation(GSD)and Serration Heat Treatment(SHT),with particular focus on microstructural ... Gradient microstructures strengthened by serrated Grain Boundaries(GBs)were achieved through a combination of Gradient Strain Deformation(GSD)and Serration Heat Treatment(SHT),with particular focus on microstructural evolution,underlying mechanisms,and the critical influencing factors.Dynamic recrystallization governed the microstructural evolution in the fine-grained and transition regions during GSD,where multiple nucleation mechanisms were active.Plastic deformation facilitated the dissolution ofγ'phase in fine-grained regions,ultimately resulting in its morphological transformation.During the subsequent SHT,serrated GBs formed within the gradient microstructures produced by prior GSD without disrupting the grain size gradient,thereby enhancing creep resistance.Two distinct mechanisms associated withγ'gbparticles governed the formation of the serrations at GBs.Owing to the stronger dragging effect of grain boundary junctions in fine-grained regions,the amplitude and wavelength of serrations in these regions were smaller than those in coarse-grained regions.Moreover,the formation of serrations exhibited a strong dependence on the inherent properties of the GBs.The random high-angle grain boundaries(HAGBs)with misorientation angles in the range of 30-59°tended to become serrated more easily during SHT due to their high mobility and the accelerated precipitation ofγ'gbparticles at them.Low-ΣHAGBs and low-angle GBs were not prone to form serrations.In particular,serration formation was completely inhibited atΣ3 twin boundaries due to their extremely low mobility and the absence ofγ'gbparticles. 展开更多
关键词 Gradient microstructures Grain boundary migration Grain boundary properties Serrated grain boundaries Serration formation mechanisms Superalloys
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Diversification of liverworts across spatial and climatic gradients in the world 认领 引用 被引量：1
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作者 Hong Qian Michael Kessler Shenhua Qian 《Plant Diversity》 SCIE CAS CSCD 2026年第2期320-329,共10页
Liverworts are an important component of terrestrial ecosystems worldwide.They have adapted to and diversified in a wide variety of environments.Investigating variation in net diversification rate is a major goal of b... Liverworts are an important component of terrestrial ecosystems worldwide.They have adapted to and diversified in a wide variety of environments.Investigating variation in net diversification rate is a major goal of biogeographers and ecologists but such investigation is lacking for liverworts at a global scale.Here,we explore global geographic patterns of mean diversification rate(MDR)within genera of liverworts,which are one of the earliest lineages of the extant land plants,and its relationship with latitude,climatic conditions,and regional species richness.We collated species lists of liverworts for each of 390 geographic units(primarily countries,provinces or states)across the world.We related MDR to geographic and current and historical climatic variables,assessed the relative importance of different sets of climatic variables on MDR,and explored the effect of MDR on species richness after accounting for major climatic factors.We analyzed the data with correlation and regression analyses,and structural equation modeling approach.We find that MDR peaks at tropical latitudes and in humid and hot environments,and that at a global scale current climate,temperature-related variables,and climatic seasonality explained more variation in MDR than Quaternary climate change,precipitation-related variables,and climatic extremes,respectively.In addition,we find a positive relationship between MDR and liverwort species richness,with the latter being directly influenced more strongly by climate than by MDR.Most importantly,we find that tropical regions of high liverwort diversity also have high current diversification rates,suggesting ongoing niche occupation.The above-described patterns are similar between the New World and Old World and between the eastern and western parts of the Old World.Our study highlights that tip diversification rates provide a complementary aspect to understand the evolution of liverwort diversity to that recovered by studying phylogenetic diversity and species richness. 展开更多
关键词 Biome Bryophyte Latitudinal diversity gradient Speciation Species richness
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Biomimetic de novo construction of hierarchically aligned and gradient-mineralized collagen for tendon-bone integrated regeneration 认领 引用
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作者 Miao Lei Hao Luo +7 位作者 Luyi Sun Songsong Shi Zhuangri Zhang Chengxuan Yu Han Gao Jun Chen Changsheng Liu Xue Qu 《Bioactive Materials》 SCIE CSCD 2026年第8期157-177,共21页
The tissues spanning from tendon to bone exhibit a highly specialized extracellular matrix(ECM)architecture,characterized by hierarchical collagen alignment and a gradient mineral composition,which together enable eff... The tissues spanning from tendon to bone exhibit a highly specialized extracellular matrix(ECM)architecture,characterized by hierarchical collagen alignment and a gradient mineral composition,which together enable efficient force transfer and guide spatially organized cellular phenotypes.However,recapitulating such complex multi-scale organization and compositional gradients to achieve integrated soft-hard tissue remains challenging.Here,we report the de novo construction of biomimetic collagen-mineral matrices that mimic both the hierar-chical organization and mineral gradient distribution of the native tendon-to-bone ECM.Through synergistic electro-assembly and post-treatment,collagen molecules self-organized into aligned fibrillar matrices with multi-scale architecture,replicating tendon-side morphology while providing robust tensile mechanics.At the opposing end,intrafibrillar and interfibrillar minerals were spatially patterned to emulate the mineral gradient from tendon to bone.This structural and compositional continuum enables smooth mechanical transition across the soft-hard tissue interface and promotes region-specific regeneration of aligned tendon-like tissue,fibrocartilage and bone.In vivo studies in rabbit models confirm that these de novo constructed matrices support histological reconstruction of multiple tissues from tendon to bone at the rotator cuff,and significantly improve functional recovery.This work presents a bottom-up biomimetic strategy for engineering multiscale collagen-based scaf-folds and demonstrates the therapeutic potential of de novo constructed matrices for multiple tissue regeneration. 展开更多
关键词 de novo biomimetic construction Hierarchical collagen matrix Gradient mineralization Electroassembly Tendon to bone regeneration
Migration behavior of magnetic nanoparticles with chain-like structure under gradient magnetic field and its influence on magnetic hyperthermia 认领 引用
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作者 Yundong Tang Xiaoyi Yang +1 位作者 Rodolfo C.C.Flesch Tao Jin 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第5期653-661,共9页
Magnetic hyperthermia uses magnetic nanoparticles(MNPs)to generate the heat used for damaging cancer cells under an alternating magnetic field.In fact,the MNPs tend to gather at the injection center and also occur the... Magnetic hyperthermia uses magnetic nanoparticles(MNPs)to generate the heat used for damaging cancer cells under an alternating magnetic field.In fact,the MNPs tend to gather at the injection center and also occur the clustering phenomenon at the same time when injecting into tumor tissue,which however can ultimately result in the excessive concentration of heat in the injection site.Thus,this study aims at improving the MNPs concentration distribution after the injection behavior by considering the action of a static gradient magnetic field,and finally optimizes both temperature situation and thermal damage degree for tumor tissue during magnetic hyperthermia.The MNPs distribution inside a proposed liver tumor is simulated by adopting a Monte Carlo method with adaptive step size,which consists of enough number of small size particles used to analyze the behavior of migration,diffusion,and chain-like phenomenon.The research results demonstrate that the introduction of static gradient magnetic field can disperse the MNPs and form a chainlike distribution inside tumor,and can then expand the distribution range of MNPs,thereby optimizing the thermal damage degree of tumor tissue.In addition,a PID controller with proper setting coefficients is also proven to be able to improve the therapeutic effect for hyperthermia by shortening the rising time to the critical temperature when proper coefficients are set properly during therapy. 展开更多
关键词 magnetic hyperthermia magnetic nanoparticles particles migration gradient magnetic field
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Unlocking the seal capacity of unconsolidated Quaternary hydrate-bearing sediments:Carbon isotope gradients as a proxy for dynamic gas trapping efficiency 认领 引用
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作者 Ya-Zhou Liu Jian-Hui Zeng +3 位作者 Jun-Cheng Qiao Gui-Wen Wang Ke-Liang Dong Shu-Ning Liu 《Petroleum Science》 SCIE EI CAS CSCD 2026年第3期1588-1605,共18页
Submarine gas hydrate systems store vast carbon inventories(∼1500–12,400 Gt C)yet pose dual risks as potential geohazard multipliers and climate feedback agents under oceanic warming.Conventional seal assessment fai... Submarine gas hydrate systems store vast carbon inventories(∼1500–12,400 Gt C)yet pose dual risks as potential geohazard multipliers and climate feedback agents under oceanic warming.Conventional seal assessment fails catastrophically in unconsolidated Quaternary hydrate-bearing sediments due to core-retrieval artifacts,hydrate morphology controls on capillary trapping,and meter-scale heterogeneity unresolved by seismic methods.Here,we pioneer methane carbon isotope(δ13C1)gradients as a dynamic proxy for seal capacity in the Qiongdongnan Basin.Integrating petrographic features,natural gas geochemical characteristics,downhole logging data,and principal component analysis(PCA)from six wells,we:(1)quantified the thermogenic gas contribution of wells W6 and W8 to be 55%–73%,and that of well W1 to be 28%–32%via binary mixing models,(2)establish that methane carbon isotope gradients>0.5‰/m diagnose effective capillary barriers,correlating with zones of pore-throat disconnection,and(3)develop a PCA-integrated logging model(cumulative variance:84.02%,R2=0.78)predicting seal capacity from conventional petrophysical parameters.Furthermore,the results validate a charge-dynamic barrier-mixing accumulation model where thermogenic gas influx elevates hydrate saturation,creating self-sealing horizons that trap underlying microbial gases and subsequently charged thermogenic gases,recorded in diagnostic methane carbon isotope reversals.This approach bridges molecular-scale fractionation and reservoir-scale processes,enabling targeted identification of high-integrity seals for optimized carbon storage and safer hydrate exploitation in rapidly deposited marginal basins. 展开更多
关键词 Seal capacity Unconsolidated hydrate-bearing sediments Carbon isotope gradients Accumulation model Qiongdongnan Basin
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Transient thermal shock induced radial gradient Cu+ -Ov-Ce3+/Ce4+boosted CO2 electroreduction to C2 products 认领 引用
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作者 Mingwang Wang Xiang Fei +2 位作者 Hui Ning Han Hu Mingbo Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2026年第3期639-645,共7页
Electrocatalytic CO2 reduction(CO2 RR)toward multi-carbon compounds is a challenging but meaningful route for carbon cycling.Copper-based catalysts are the most promising candidate for C2+generation due to th... Electrocatalytic CO2 reduction(CO2 RR)toward multi-carbon compounds is a challenging but meaningful route for carbon cycling.Copper-based catalysts are the most promising candidate for C2+generation due to their unique C–C coupling activity,yet the in situ reduction from Cu+ to Cu0 under cathodic potentials causes the catalyst deactivation.Herein,we develop a transient thermal shock strategy to embed Cu+ species into CeO2 lattices,constructing a CuOx/CuCeOxcatalyst with a radial gradient Cu+ -Ov-Ce3+/Ce4+structure.Depth-profiling X-ray photoelectron spectroscopy(XPS)and density functional theory(DFT)calculations reveal that mismatched metal/oxygen diffusion kinetics drive continuous electron transfer from surface Cu+ to bulk Ce3+/Ce4+via oxygen vacancies(Ov),forming a dynamic“self-sacrificial”structure to preserve surface Cu+ states.In CO2-saturated 0.1 M KHCO3,the optimized CuOx/CuCeOx-10 achieves a high C2 Faradaic efficiency(FE)of 85.8%at-1.4 V vs.RHE.In situ attenuated total reflection surface-enhanced infrared adsorption spectroscopy(ATR-SEIRAS)identifies the key intermediates of C2 are*OCCO and*OCCOH,while DFT reveals a drastic reduction of C–C coupling barrier from 0.842 to0.274 eV.This work demonstrates kinetically tailored metal-support interactions,enabling oxidationstate control for pathway-selective catalysis. 展开更多
关键词 Carbon dioxide Metal-support interactions Gradient structure
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Mechanisms driving anammox bacteria enrichment in constructed wetlands for self-purification of high-nitrogen polluted wastewater:Environmental gradients and microbial interactions 认领 引用
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作者 Lin Liu Jie Li +2 位作者 Yu Xin Quan-Bao Zhao Yu-Ming Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第1期44-53,共10页
Anammox bacteria in constructed wetlands(CWs)play pivotal role in sustainable nitrogen transformation,yet existing studies lack comprehensive analysis of environmental gradients and microbial interactions,both key fac... Anammox bacteria in constructed wetlands(CWs)play pivotal role in sustainable nitrogen transformation,yet existing studies lack comprehensive analysis of environmental gradients and microbial interactions,both key factors in anammox bacteria enrichment.This study investigated the mechanisms driving anammox bacteria enrichment in lab-scale simulated CWs treating high-nitrogen wastewater,focusing on bacterial community re-sponses across wetland layers with various strategies,including continuous up-flow influent,nitrogen loading increase,effluent recirculation,intermittent influent,and anammox bacteria inoculation.Results showed that total relative and absolute abundances of anammox bacteria ranged from 0.77%to 12.50%and from 0.13 to 6.46×107 copies/g,respectively.Dissolved oxygen and pH had significant positive correlations with the absolute abundance of anammox bacteria,while organic matter and nitrate negatively impacted their relative abundance.Permutational multivariate analysis of variance indicated that spatial heterogeneity explained more variation in anammox bacteria abundance(43.44%)compared to operational strategies(8.58%).In terms of microbial interactions,60 dominant species exhibited potential correlations with anammox bacteria,comprising 170 interactions(105 positive and 65 negative),which suggested that anammox bacteria generally foster cooperative relationships with dominant bacteria.Notably,significant interspecies interactions were observed between Candidatus Kuenenia(dominant anammox bacteria in CWs)and species within the genera Chitinivibrio-nia and Anaerolineaceae,suggesting that microbial interactions primarily manifest as indirect facilitative effects rather than direct mutualistic relationships.Given that the Normalized Stochasticity Ratio in CWs were<50%,this study inferred that environmental gradients have greater influence on anammox bacteria than microbial interactions. 展开更多
关键词 Self-purifying capacity Anammox bacteria Environmental gradient Constructed wetland Co-occurrence network Nature-based solution
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Evolutionary Characteristics of Linear Free-radical Polymerization Behavior under Gradient Condition 认领 引用
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作者 Hui Li Bing-Bing Pan +4 位作者 Yi-Yi Zhang Wen Li Zi-Jian Xue Zhen-Bin Chen Hong Liu 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2026年第8期2691-2703,I0018,共13页
This study investigates the evolution of free-radical polymerization under spatially graded conditions by constructing a position-dependent reaction probability model.Given the strong temperature dependence of thermal... This study investigates the evolution of free-radical polymerization under spatially graded conditions by constructing a position-dependent reaction probability model.Given the strong temperature dependence of thermal initiators,spatial temperature variations significantly affect both local monomer reactivity and the macroscopic evolution of polymer structures.Understanding this coupling is crucial for designing gradient-controlled synthesis strategies.The dissipative particle dynamics(DPD)method was employed to investigate free radical polymerization under gradient temperature conditions.IncreasingΔT enhances spatial heterogeneity:high-temperature regions form dense networks with lower molecular weights(Mn and Mw)due to rapid initiation and frequent termination.In contrast,low-temperature regions yield higher molecular weights and expanded chain conformations()resulting from longer radical lifetimes.These structural differences further govern pore evolution:porosity decreases rapidly and reaches lower final values in high-temperature zones,while low-temperature regions exhibit delayed evolution but higher final porosity.This study demonstrates that the precise control of polymer growth orientation,molecular weight distribution,and porous morphology can be achieved by incorporating gradient conditions,thereby establishing a new paradigm for the targeted synthesis of gradient functional materials. 展开更多
关键词 Free radical polymerization Gradient structure Dissipative particle dynamics Polymerization kinetics
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Bio-Inspired Continuous Gradient Nanocomposites for Ultrahigh-Temperature Dielectric Energy Storage at 150℃-200℃ 认领 引用
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作者 Jian Wang Weihao Dai +6 位作者 Qian Zhang Biyun Peng Yifei Zhang Sen Liang Wei Ma Fangfang Wu Di Zhou 《Rare Metals》 SCIE EI CAS CSCD 2026年第6期498-506,共9页
Dielectric polymers commonly suffer from severe performance degradation above 150℃,hindering advanced power systems.Herein,we demonstrate a polyetherimide(PEI)nanocomposite that overcomes this by mimicking the gradie... Dielectric polymers commonly suffer from severe performance degradation above 150℃,hindering advanced power systems.Herein,we demonstrate a polyetherimide(PEI)nanocomposite that overcomes this by mimicking the gradient architecture of nacre and bamboo,incorporating a continuous vertical gradient of fluorinated boron nitride nanosheets(BNNS‐F)through sequential electrospinning.This bio‐inspired design not only reinforces mechanical and thermal stability,but also generates a spatially gradient distribution of deep charge traps.The resulting progressive trap energy barrier effectively suppresses charge transport,impedes electrical treeing propagation,and significantly reduces conduction losses at elevated temperatures.Consequently,our continuous gradient PEI/BNNS‐F cg nanocomposite achieves an exceptional breakdown strength(Eb)of 626 MV m−1and a discharged energy density(Ud)of 6.21 J cm−3with 90%efficiency at 150℃,surpassing most reported polymer‐based dielectrics.Remarkably,it retains a high Udof 3.89 J cm−3at 200℃,along with outstanding cycling stability over 10,000 cycles.This work introduces a new paradigm for controlling charge dynamics through continuous gradient structures,enabling high‐performance energy storage under extreme conditions. 展开更多
关键词 bio‐inspired architecture continuous gradient electrical properties high‐temperature performance nanocomposites
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Gradient structured nanocrystalline-amorphous Fe-based composite coatings with superior strength and wear resistance 认领 引用
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作者 Guoliang Ma Hongzhi Cui +4 位作者 Qing Du Xiaojie Song Hao Zhang Hongwei Zhang Hao Chen 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2026年第1期144-155,共12页
Gradient nanocrystalline–amorphous nanostructures are considered to be an effective approach to achieve exceptional strength–plasticity synergy,with significantly improved wear performance.Here,gradient nanostructur... Gradient nanocrystalline–amorphous nanostructures are considered to be an effective approach to achieve exceptional strength–plasticity synergy,with significantly improved wear performance.Here,gradient nanostructured Fe-based coatings were successfully fabricated by extremely high-speed-rate laser deposition and remelting.The microstructure evolution along the depth direction varies in a nanocrystalline,equiaxial dendrites,columnar dendrites gradient,respectively.Noticeably,amorphous grain boundaries and carbide nanoprecipitates could be identified within the topmost surface nanocrystalline layer owing to the extremely high cooling rate during remelting,which exhibits the highest hardness and wear resisance(microhardness of ~1136 HV,and wear rate of 4.36×10−6mm3/(m N)).The superior wear resistance is mainly attributed to the synergistic nanocrystalline–amorphous deformation and gradient refinement effects.Meanwhile,multi-scale carbides effectively impede dislocation motion and further improve strength and wear resistance at different depths.This gradient structure provides promising insights into the design of high-performance wear-resistant alloys. 展开更多
关键词 Gradient nanostructure Nanocrystalline-amorphous structure Extremely high-speed-rate laser remelting Wear resistance
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Investigation and application of diffusive gradients in thin films for in situ monitoring of pharmaceuticals in surface water during rainfall events 认领 引用
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作者 Hongmei Cao Qingshan Li +2 位作者 Qingwei Bu Lei Yang Jianfeng Tang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第6期382-393,共12页
Pharmaceutically active compounds have garnered increased attention as emerging contaminants due to their widespread presence and potential ecological impacts.This study conducted a field evaluation under varied rainf... Pharmaceutically active compounds have garnered increased attention as emerging contaminants due to their widespread presence and potential ecological impacts.This study conducted a field evaluation under varied rainfall conditions,assessing the effects of rainfall intensity and duration on pharmaceutical concentrations.Grab sampling was complemented by the deployment of diffusive gradients in thin films(DGT)passive samplers along two urban rivers in Beijing,China.Twenty-four target pharmaceuticals were detected,with concentrations ranging from 370 to 686 ng/L in the Beixiao River and 376 to 610 ng/L in the Qing River.Rainfall influenced pharmaceutical concentrations through either dilution or enhancement,depending on local factors.Rainfall had a minimal impact on DGT performance,while biofouling showed compound-specific effects.For about 70%of the pharmaceuticals,hydrophilic poly tetrafluoroethylene(PTFE)membranes used over 9–15 days effectively minimized biofouling influence(Mbiofouled/Mclean>0.8).The effectiveness of DGT for long-term monitoring depended on the biofilm formation time.Overall,DGT proved to be a reliable tool for accurately characterizing pharmaceutical concentrations in dynamic water systems.This study represents the first attempt to evaluate DGT performance for pharmaceuticals under fluctuating concentration scenarios in the field,providing valuable insights into the occurrence and environmental behavior of these contaminants. 展开更多
关键词 Pharmaceuticals Diffusive gradients in thin films(DGT) Rainfall event Passive sampling Biofouling
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Decoupling strength-damage trade-offs in additively manufactured alloys via engineered strain gradient 认领 引用
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作者 Jing PENG Hui FENG +2 位作者 Hong WU Jia LI Qihong FANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2026年第5期1041-1064,共24页
The strength and damage tolerance of additively manufactured(AM)alloys are significantly influenced by their heterogeneous microstructures.However,establishing quantitative relationships between these microstructural ... The strength and damage tolerance of additively manufactured(AM)alloys are significantly influenced by their heterogeneous microstructures.However,establishing quantitative relationships between these microstructural characteristics and the resulting mechanical properties remains a challenge.Here,a microstructure-based mechanical model is established based on the heterogeneous grain distribution within the melt pool,with particular emphasis on the strain gradient effect arising from the deformation incompatibility between distinct grain regions.The strengthening mechanisms and local deformation response of AM alloys are elucidated with the finite element method(FEM).The strain gradient effect generated by the deformation incompatibility between the columnar and equiaxed grain regions enhances the local stress near the equiaxed-columnar interface,which is an important reason for the overall work hardening.Concurrently,the local stress concentration makes it easier to reach the critical stress for microcrack nucleation at the interface,leading to failure and a lack of synergy between the strength and damage tolerance.The prediction of the crack initiation location based on the simulation results is consistent with the previous experiments.By further quantitatively predicting the comprehensive effects of melt pool size on strength,strain hardening,and damage rate,small-melt-pool structures produce high strength,but microcracks originate early,whereas large-melt-pool structures have weak strengthening effects but fast damage evolution in the later stages of deformation.This study provides a pathway to predict the optimal melt pool size for achieving superior combinations of strength and damage tolerance in AM alloys. 展开更多
关键词 additive manufacturing strain gradient strain hardening damage tolerance microcrack nucleation
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Tailoring layer-by-layer gradient porous ultra-thick electrodes via solvent-free processing method for high-areal-capacity and high-rate lithium-ion batteries 认领 引用
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作者 Haotian Yang Jinke Shen +9 位作者 Nan Qin Yaoxin Du Yuhan An Chen Hu Yifan Li Wenlong Cai Cunman Zhang Zonghai Chen Jim P.Zheng Liming Jin 《Chinese Chemical Letters》 SCIE CAS CSCD 2026年第7期634-639,共6页
Ultra-thick electrodes(UTEs)hold great promise for high-energy-density lithium-ion batteries(LIBs),yet the practical application is hindered by challenges in precise fabrication and reaction kinetics modification.In t... Ultra-thick electrodes(UTEs)hold great promise for high-energy-density lithium-ion batteries(LIBs),yet the practical application is hindered by challenges in precise fabrication and reaction kinetics modification.In this contribution,a solvent-free processing method is introduced to tailor UTEs through layerby-layer fabrication with positive,uniform,and negative gradient porosity from the separator side to the current collector side,denoted as P-UTEs,U-UTEs,and N-UTEs.In contrast to conventional slurry coating,the proposed solvent-free approach effectively circumvents capillary stress,thereby facilitating the fabrication of crack-free UTEs(>300μm)while simultaneously mitigating environmental toxicity concerns.The three-layer N-UTEs(>220μm)with a gradient porosity of(~34%,~31%,~27%)deliver an exceeding areal capacity over 5 m Ah/cm2 at 0.29 mA/cm2 and a high-capacity retention over 62% at 2.9 m A/cm2,indicating a favorable balance between the areal capacity and the high-rate behavior.Detailed mechanistic simulations reveal that the multi-center reaction pathways enabled by enhanced ionic accessibility in N-UTEs significantly improve reaction kinetics.This work offers new insights into the gradient porosity tailoring for high-areal-capacity and high-rate UTEs for the next generation LIBs. 展开更多
关键词 Gradient porous structure Electrode kinetics Ultra-thick electrodes Solvent-free processing method Lithium-ion battery
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Mitigating reaction heterogeneity in Li-rich layered cathodes through surface-phase regulation enabled by tailored concentration gradients engineering 认领 引用
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作者 Yujia Wu Yuefeng Su +9 位作者 Jinyang Dong Yun Lu Jianan Hao Huiquan Che Teng Yang Yiya Wang Ning Li Yibiao Guan Feng Wu Lai Chen 《Green Energy & Environment》 SCIE EI CAS CSCD 2026年第5期1309-1323,共15页
Lithium-rich layered oxides are promising cathodes for high-energy lithium-ion batteries,yet their applications are hindered by voltage decay,structural instability,and heterogeneous reaction dynamics.These degradatio... Lithium-rich layered oxides are promising cathodes for high-energy lithium-ion batteries,yet their applications are hindered by voltage decay,structural instability,and heterogeneous reaction dynamics.These degradations stem from the coexistence of Li2MnO3and LiMO2domains,which exhibit distinct redox kinetics and trigger phase mismatch during cycling.To address this challenge,we propose a tailored concentration gradient design that regulates the spatial distribution of transition metals.Nickel is intentionally enriched near the surface while manganese dominates the interior,creating a coordinated balance between interfacial stability and bulk capacity retention.Regulating Ni content deliberately induces a moderate Li/Ni cation-mixed phase,and the tailored gradient builds a surface composite structure that stabilizes the layered framework and suppresses interfacial degradation.This architecture homogenizes redox activation,alleviates surface-bulk reaction mismatch,and retards the formation of spinel or rock-salt phases.Structural characterizations with in situ and ex situ methods confirm coherent variations in composition and valence states.Electrochemical analyses demonstrate suppressed voltage hysteresis,smaller polarization,and enhanced cycling stability.Simulations further verify homogeneous ion transport with stabilized phase evolution,collectively validating that surface-phase regulation enabled by tailored concentration gradients effectively mitigates reaction heterogeneity in Li-rich layered cathodes.The findings highlight surface-phase regulation enabled by tailored concentration gradients as a scalable strategy that mitigates reaction heterogeneity in lithium-rich layered cathodes and extends applicability to other cathode systems for large-scale energy storage. 展开更多
关键词 Li-rich layered cathodes Tailored concentration gradient Transition metal distribution Reaction heterogeneity suppression Cycling stability
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Effect of Heterogenous Gradient Structure Induced by High Cu Content on Nanocrystallization Process and Magnetic Properties of Fe-Based Nanocrystalline Alloys 认领 引用
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作者 Lei Xie Qiang Li +4 位作者 Jing Zhou Yaqiang Dong Aina He Chuntao Chang Baoan Sun 《Rare Metals》 SCIE EI CAS CSCD 2026年第4期744-755,共12页
The pre-existingα-Fe crystals have important effects on the precipitation and growth of nanocrystals and finally determine the comprehensive soft magnetic properties(SMPs)of the nanocrystalline alloys(NAs).In this wo... The pre-existingα-Fe crystals have important effects on the precipitation and growth of nanocrystals and finally determine the comprehensive soft magnetic properties(SMPs)of the nanocrystalline alloys(NAs).In this work,a high content of Cu elements has been added to Nanomet-type alloys to enhance the gradient heterogeneity in order to well control the nanocrystalline process of amorphous alloys.Crystallization kinetics reveal that α-Fe crystals in the free-side layer exhibit higher nucleation and growth activation energies,leading to a slower crystallization rate than in the wheel-side layer.This inhomogeneous crystallization behavior reduces the uneven distribution of α-Fe crystals in the as-spun high Cu content ribbons.Consequently,the Fe82.5Si3.5B9P2C1Cu1.7 alloy achieves superior SMPs through nanocrystallization,including high Bs(~1.82 T),low Hc(10,000@1 kHz)across wide TA and tA ranges.Compared to low-temperature long-time and lowtemperature short-time heat treatments,high-temperature short-time heat treatment results in better SMPs.This is because it intensifies the competition between the fast nucleation/growth of newα-Fe crystals and the slower growth of pre-existing crystals.These findings deepen the understanding of crystallization processes in gradient inhomogeneous materials and guide the optimization of annealing processes for improved performance in Fe-based NAs. 展开更多
关键词 gradient microstructure magnetic property nanocrystalline alloy non‑uniform crystallization mechanism
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Microstructure and tribological behavior of gradient nanostructured Inconel 625 alloy treated via plate surface mechanical rolling 认领 引用
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作者 Yan-jiang WANG Zhi JIA +4 位作者 Jin-jin JI Luen-chow CHAN Chi-ping LAI Xian-zheng LU De-xue LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2026年第4期1166-1182,共17页
The effects of plate surface mechanical rolling treatment(P-SMRT)on the microstructure and tribological behavior of Inconel 625 alloy were investigated.The results reveal that P-SMRT induced the formation of a gradien... The effects of plate surface mechanical rolling treatment(P-SMRT)on the microstructure and tribological behavior of Inconel 625 alloy were investigated.The results reveal that P-SMRT induced the formation of a gradient nanostructure(GNS)strengthening layer with a thickness of 700μm on the surface of Inconel 625 alloy.The GNS formation was driven by the interaction between deformation twins and dislocations,leading to the development of shear bands that transformed into ultrafine grains and nanograins.The hardness of the samples with GNS was 192.7%higher than that of the untreated samples.In addition,the tribological properties of the P-SMRT and untreated samples were investigated through dry sliding friction and wear tests.These findings indicate that the P-SMRT induced GNS accommodated greater strain,reduced strain localization,and inhibited surface material exfoliation and transfer,thereby significantly enhancing the wear resistance of Inconel 625 alloy. 展开更多
关键词 plate surface mechanical rolling treatment gradient nanostructures deformation twins tribological behavior Inconel 625 alloy
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Biodiversity of Amphibians Along the Elevational Gradient of Mount Leigong: Checklist, Distribution, and Conservation 认领 引用
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作者 Tuo SHEN Chaobo FENG +5 位作者 Xiujun TANG Caichun PENG Jing LIU Xue GOU Lang MU Haijun SU 《Asian Herpetological Research》 SCIE CAS CSCD 2026年第1期62-66,共5页
Dear Editor,Mountain systems have long been refuges for many species,often viewed as"islands"that promote speciation due to geographic isolation(Rahbek et al.,2019).Their high environmental heterogeneity fos... Dear Editor,Mountain systems have long been refuges for many species,often viewed as"islands"that promote speciation due to geographic isolation(Rahbek et al.,2019).Their high environmental heterogeneity fosters centers of endemism,and they harbor over 85%of global species diversity(Zhao et al.,2022).Consequently,mountains are key systems for exploring biodiversity patterns along elevational gradients,where species richness often follows four recognized models:monotonic decrease,unimodal pattern(forward and backward peak patterns),and low plateau followed by a decrease along the elevational gradient(McCain et al.,2010). 展开更多
关键词 species richness conservation biodiversity elevational gradient amphibians biodiversity patterns Mount Leigong checklist
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Bioinspired Layered-Gradient Nanocomposites for Intelligent Electromagnetic Skins with GHz-THz Wave Absorption,Shielding,and Solvent-Driven Actuation 认领 引用
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作者 Xianyuan Liu Yang Zhao +4 位作者 Yali Zhang Xuechun Cui Ying Xue Xianyong Lu Junwei Gu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2026年第10期307-325,共19页
The development of intelligent electromagnetic skins demands scalable films integrating gigahertz(GHz)-terahertz(THz)wave absorption,electromagnetic interference(EMI)shielding,and programmable actuation.Here,we report... The development of intelligent electromagnetic skins demands scalable films integrating gigahertz(GHz)-terahertz(THz)wave absorption,electromagnetic interference(EMI)shielding,and programmable actuation.Here,we report a bioinspired bamboo-like layered-gradient system fabricated via scalable vacuum filtration,in which two types of films are constructed with distinct functionalities:a low-poly(3,4-ethylenedioxythiophene)(PEDOT)content film for microwave absorption and a high PEDOT content film for conductive network-enabled EMI shielding.The films precisely assemble Al-Fe3O4nanosheets,aramid nanofibers,and PEDOT into an asymmetric architecture.A monotonic through-thickness gradient in composition creates a tailored impedance profile and strong anisotropy while minimizing conductive filler content.This design achieves effective microwave absorption at low PEDOT loading(minimum reflection loss:−56.6 dB at 2.2 mm in the X-band).With increased PEDOT content,a percolative network is constructed,enabling Joule heating(233℃at 20 V)and efficient EMI shielding(42.0 dB in the GHz band and 57.8 dB in the THz band).Beyond electromagnetic performance,the gradient architecture enables programmable,ethanol-triggered anisotropic actuation via differential swelling.The films also exhibit excellent thermal stability,mechanical robustness,and flexibility,ensuring reliability in harsh environments.Collectively,this gradient architecture provides a scalable platform for intelligent electromagnetic skins integrate magnetic-dielectric coupling,conductive network tuning,and stimuli-responsive actuation. 展开更多
关键词 Electromagnetic interference shielding Electromagnetic wave absorption Gradient architecture Terahertz Intelligent actuation
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A self-leveling-like effect for dendrite-free lithium metal anodes via gradient-enhanced electric field hosts 认领 引用
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作者 Yi Yang Chang Yu +8 位作者 Qiang Zhang Shuo Liu Junting Dong Weizhe Liu Wei Zhou Jiani Chen Wenbin Li Shiqiang Liu Jieshan Qiu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2026年第4期258-268,I0007,共11页
For Li metal battery,Li metal anodes severely suffer from dendritic growth due to heterogeneous electrodeposition,which inhibits their development and application.While extensive studies for Li dendrite suppression em... For Li metal battery,Li metal anodes severely suffer from dendritic growth due to heterogeneous electrodeposition,which inhibits their development and application.While extensive studies for Li dendrite suppression empirically utilize 3D hosts to homogenize the micro-scaled electric field within the host,the inherent correlation between host structure and electric field distribution and underlying principles remains elusive,and the corresponding design of hosts to enhance the electric effects remains challenging.Here,the host microstructure-electric field correlations are established via COMSOL simulations and demonstrate the enhanced redistribution of the electric field through structural redesign of hosts.Based on a structure model,an enhanced gradient electric field host(EGHx)with a supercontinuous gradient pore architecture is fabricated with the assistance of the porogen dissolution method,which achieves a self-leveling-like Li deposition through spatially programmed charge redistribution.Through further structural optimization,the EGH2(with 2 wt%porogen)exhibits an~98%Coulombic efficiency(CE)over 350 cycles(1 mA cm-2,1 mAh cm-2).Further multidimensional testing with argon protection reveals the role of the host in modulating solid-electrolyte interphase(SEI)composition.Accordingly,the EGH2 enables stable dendrite-free Li plating/stripping behaviors for 2100 h.The assembled full cell and pouch cell also display stable cycling performance with an LFP cathode. 展开更多
关键词 Enhanced gradient electric field Carbon host Li metal anodes Supercontinuous pore
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