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Effects of inhibitor KCl on shale expansibility and mechanical properties 被引量:9
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作者 Xiangchao Shi Lei Wang +2 位作者 Jianhua Guo Qiang Su Xiao Zhuo 《Petroleum》 CSCD 2019年第4期407-412,共6页
The expansibility and mechanical properties of shale are significantly influenced by water-based muds(WBMs);thus,it is necessary to mitigate this effect to avoid borehole instabilities in drilling operation.Potassium ... The expansibility and mechanical properties of shale are significantly influenced by water-based muds(WBMs);thus,it is necessary to mitigate this effect to avoid borehole instabilities in drilling operation.Potassium chloride(KCl)is usually used as inhibitor to reduce hydration of shales.In this study,we investigated the inhibitory efficiency of KCl on shale through a series of experiments,including dynamic linear swelling(DLS)tests and uniaxial compressive strength(UCS)tests,to provide reference for the design of WBMs.These tests were conducted on shale samples soaked in KCl solution for 24,48,72,and 96 h with saline concentrations of 0%,2%,4%,6%,and 8%.Experimental results show that samples with microcracks and bedding fissures have the highest swelling increase and the largest strength reduction after immersion in solution.The swelling potential decreased with increasing KCl concentration.In addition,KCl exhibited a certain inhibitory effect on the weakening of the mechanical properties of samples.An increase in the KCl concentration increases the compressive strength and elastic modulus,and decreases the Poisson's ratio.However,in terms of homogeneous samples,the UCS test results show that exposure to water is weakly related to weakening of the mechanical properties of shale samples.We found that immersing the shale in KCl solution for a longer time decreases the compressive strength,increases the Poisson's ratio,and decreases the elastic modulus. 展开更多
关键词 KCL INHIBITOR expansibility Mechanical properties Bedding fissures
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Bound states in the continuum for encoded imaging
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作者 HOU Shuai-Xing YANG Si-Jia +1 位作者 SHEN Yun DENG Xiao-Hua 《红外与毫米波学报》 北大核心 2026年第1期90-96,共7页
Metasurfaces are artificial structures that can finely control the characteristics of electromagnetic waves at subwavelength scales,and they are widely used to manipulate the propagation,phase,amplitude,and polariza⁃t... Metasurfaces are artificial structures that can finely control the characteristics of electromagnetic waves at subwavelength scales,and they are widely used to manipulate the propagation,phase,amplitude,and polariza⁃tion of light.In this work,a bound state in the continuum(BIC)structure based on a metallic metasurface is pro⁃posed.By adjusting the metallic structure using CST and COMSOL software,a significant quasi-BIC peak can be achieved at a frequency of 0.8217 terahertz(THz).Through multi-level expansion analysis,it is found that the electric dipole(ED)is the main factor contributing to the resonant characteristics of the structure.By leveraging the characteristics of BIC,an imaging system was created and operated.According to the simulation results,the imaging system demonstrated excellent sensitivity and resolution,revealing the great potential of terahertz imag⁃ing.This research not only provides new ideas for the creation of BIC structures but also offers an effective refer⁃ence for the development of high-performance terahertz imaging technology. 展开更多
关键词 metasurface bound states in the continuum TERAHERTZ multi-level expansion IMAGING
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Cosmic Acceleration and the Hubble Tension from Baryon Acoustic Oscillation Data
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作者 Xuchen Lu Shengqing Gao Yungui Gong 《Chinese Physics Letters》 2026年第1期327-332,共6页
We investigate the null tests of cosmic accelerated expansion by using the baryon acoustic oscillation(BAO)data measured by the dark energy spectroscopic instrument(DESI)and reconstruct the dimensionless Hubble parame... We investigate the null tests of cosmic accelerated expansion by using the baryon acoustic oscillation(BAO)data measured by the dark energy spectroscopic instrument(DESI)and reconstruct the dimensionless Hubble parameter E(z)from the DESI BAO Alcock-Paczynski(AP)data using Gaussian process to perform the null test.We find strong evidence of accelerated expansion from the DESI BAO AP data.By reconstructing the deceleration parameter q(z) from the DESI BAO AP data,we find that accelerated expansion persisted until z■0.7 with a 99.7%confidence level.Additionally,to provide insights into the Hubble tension problem,we propose combining the reconstructed E(z) with D_(H)/r_(d) data to derive a model-independent result r_(d)h=99.8±3.1 Mpc.This result is consistent with measurements from cosmic microwave background(CMB)anisotropies using the ΛCDM model.We also propose a model-independent method for reconstructing the comoving angular diameter distance D_(M)(z) from the distance modulus μ,using SNe Ia data and combining this result with DESI BAO data of D_(M)/r_(d) to constrain the value of r_(d).We find that the value of r_(d),derived from this model-independent method,is smaller than that obtained from CMB measurements,with a significant discrepancy of at least 4.17σ.All the conclusions drawn in this paper are independent of cosmological models and gravitational theories. 展开更多
关键词 baryon acoustic oscillation bao data cosmic accelerated expansion dimensionless hubble parameter reconstructing deceleration parameter null testwe accelerated expansion null tests gaussian process
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Tailoring pretreatment-mediated microcrystalline structure of starch-based hard carbon for high-performance sodiumion batteries
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作者 Shaojie Qin Zhenyuan Xie +5 位作者 Xianrui Wu Yanbing Cheng Yiyong Zhang Ziyi Zhu Shuang Zhou Xue Li 《Materials Futures》 2026年第2期77-91,共15页
The principal challenge in optimizing biomass-derived hard carbon(HC)is the concurrent enhancement of specific capacity,cycling durability,and rate performance,as these properties are closely related to the disordered... The principal challenge in optimizing biomass-derived hard carbon(HC)is the concurrent enhancement of specific capacity,cycling durability,and rate performance,as these properties are closely related to the disordered carbon network and abundant pore structure.However,inadequate controllability of morphology,insufficiently regulated pore structures,and the complexity of post-processing modifications hinders the practical application of HC.In this work,a high-temperature and high-pressure expansion pretreatment technique is proposed to regulate the structure of starch precursors,enabling the precise design of ordered graphitic-like microcrystals and closed pores within HC.The optimized starch-based HC displayed remarkable electrochemical efficiency,with a reversible capacity of 332.0 mAh g^(-1),an initial Coulombic efficiency of 90.4%,and stable cycling over 3000 cycles.Meanwhile,advanced full-cell utilizing Na4Fe3(PO_(4))_(2)P_(2)O_(7) cathode achieve stable cycling performance exceeding 1000 cycles,demonstrating outstanding performance.This research innovatively employs a green expansion process to achieve structural regulation of HC,thereby providing an environmentally friendly and economically viable technical pathway for its large-scale production. 展开更多
关键词 sodium-ion batteries biomass hard carbon anode STARCH expansion technology
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The Curtain Rises on Consumption
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作者 LI YIN 《ChinAfrica》 2026年第3期54-56,共3页
China’s booming performing arts sector is reshaping cultural experiences and creating vibrant new spaces for leisure,tourism and creativity The year 2025 marked a period of vigorous expansion for China’s performing ... China’s booming performing arts sector is reshaping cultural experiences and creating vibrant new spaces for leisure,tourism and creativity The year 2025 marked a period of vigorous expansion for China’s performing arts sector,as the industry evolved from a traditional entertainment field into a comprehensive engine of cultural consumption. 展开更多
关键词 expansion performing arts CREATIVITY TOURISM LEISURE CONSUMPTION reshaping cultural experiences cultural experiences
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Phytochrome-interacting factor3(PIF3)orthologs orchestrate stem elongation and wood formation in Populus
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作者 Xingyue Xiao Hongli Cheng +6 位作者 Jianghai Mo Fan Sun Qin Song Chengshan Zhang Pan Yang Keming Luo Hongbin Wei 《Journal of Genetics and Genomics》 2026年第3期389-400,共12页
Phytochrome-interacting factors(PIFs)have been established as negative regulators of vascular patterning and xylem differentiation in the herbaceous plant Arabidopsis thaliana,however,the regulatory role of PIFs in se... Phytochrome-interacting factors(PIFs)have been established as negative regulators of vascular patterning and xylem differentiation in the herbaceous plant Arabidopsis thaliana,however,the regulatory role of PIFs in secondary growth in woody species remains unclear.Here,we examines the expression patterns and involvement of PtoPIF3.1 and PtoPIF3.2 during stem growth and secondary xylem development in Populus tomentosa.Overexpression of either PtoPIF3.1 or PtoPIF3.2 significantly enhances both longitudinal stem growth and radial wood development.Conversely,Ptopif3.1 and Ptopif3.2 mutants generated by CRISPR-mediated genome editing exhibit reciprocal phenotypic defects.Exogenous auxin application partially restores the phenotypes of Ptopif3.1 and Ptopif3.2 mutants,and the auxin biosynthesis-deficient mutant Ptoyuc8 exhibits developmental abnormalities similar to those observed in Ptopif3 mutants.Further analysis reveal that PtoPIF3s directly bind to and activate expression of PtoYUC8 and cell expansion-related genes PtoEXPA1.1/1.2,while modulating cambial division and expression of secondary xylem development marker genes(PtoWOX4,PtoANT,PtoCYCD3s,and PtoHB7/8)through auxin-mediated signaling.Together,our findings establish PtoPIF3.1/3.2 as key regulators that coordinate stem elongation and secondary growth in Populus,highlighting the functional divergence of PIF homologs between herbaceous and woody species. 展开更多
关键词 Populus tomentosa PIF Auxin biosynthesis Cell expansion Xylem development Synergistic regulation
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Tailoring twisted WS_(2) structure with strain-self-relaxation for ultra-high capacity potassium ion batteries
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作者 Yongpeng Cui Wenting Feng +9 位作者 Lina Ge Xinru Wei Lingmei Wang Yajun Wang Chong Xu Yuting Wang Wang Yang Debin Kong Wei Xing Yongfeng Li 《Journal of Energy Chemistry》 2026年第3期319-327,共9页
The structural stress/strain induced by K-ion intercalation remains a critical challenge for K-ion batteries.To address this,a dopamine-intercalated WS_(2) hybrid(Dam-WS1.87)with a unique strain-self-relaxation archit... The structural stress/strain induced by K-ion intercalation remains a critical challenge for K-ion batteries.To address this,a dopamine-intercalated WS_(2) hybrid(Dam-WS1.87)with a unique strain-self-relaxation architecture was fabricated.Interestingly,the WS_(2) matrix undergoes a structural transformation owing to the intense infiltration effect of dopamine molecules,expanding interlayer spacing(0.813 nm)and introducing 6.5%S-vacancies while preserving high compaction density(4.0874 gcm^(-3)).The engineered structure demonstrates remarkable mechanical stability,exhibiting only 19.0%crystallite expansion upon full potassiation(vs.101.3%for pristine WS_(2)),demonstrating efficient strain alleviation through its strain-self-relaxation architecture.As a result,Dam-WS1.87delivers reversible capacities of 312.6 m A h g^(-1)/1277.7 mA h cm^(-3)at 0.125 C,along with superior rate capability(maintaining 210.4 m A h g^(-1)at 5 C)and unprecedented cycling stability(85.3%capacity retention after 1400 cycles at 1 C).This work provides new insights into designing strain-tolerant electrode materials for nextgeneration energy storage systems. 展开更多
关键词 Potassium ion battery Volume expansion Strain-self-relaxation DOPAMINE WS_(2)
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On AlN_(P)/Mg-Zn-Cu cast composites with low expansion and high thermal conductivity
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作者 Shu-sen Wu Lu Chen +2 位作者 Shu-lin Lü Wei Guo Jian-yu Li 《China Foundry》 2026年第1期101-107,共7页
There is an urgent need to develop magnesium-matrix materials that exhibit both high thermal conductivity and low thermal expansion to ensure compatibility with chips.This study aims to develop a Mg-Zn-Cu alloy with h... There is an urgent need to develop magnesium-matrix materials that exhibit both high thermal conductivity and low thermal expansion to ensure compatibility with chips.This study aims to develop a Mg-Zn-Cu alloy with high thermal conductivity.Furthermore,it explores the preparation of AlN_(P)/Mg-Zn-Cu composites featuring low coefficients of thermal expansion.The stir casting method was utilized to fabricate the composites and an investigation was conducted to examine their microstructure and thermal properties.Results indicate that the addition of AlN_(P)reduces the thermal expansion coefficient while maintaining relatively high thermal conductivity.Specifically,the AlN_(P)/Mg-0.5Zn-0.5Cu composite with 30wt.%AlN_(P)achieves a thermal conductivity of 132.7 W·m^(-1)·K^(-1)and a thermal expansion coefficient of 18.5×10^(-6)K^(-1),rendering it suitable for electronic packaging applications where thermal management is critical. 展开更多
关键词 thermal expansion thermal conductivity magnesium-matrix composites Mg-Zn-Cu alloy
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Structural and Helix Reversal Defects of Carbon Nanosprings:A Molecular Dynamics Study
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作者 Alexander V.Savin Elena A.Korznikova Sergey V.Dmitriev 《Computers, Materials & Continua》 2026年第2期445-464,共20页
Due to their chiral structure,carbon nanosprings possess unique properties that are promising for nanotechnology applications.The structural transformations of carbon nanosprings in the form of spiral macromolecules d... Due to their chiral structure,carbon nanosprings possess unique properties that are promising for nanotechnology applications.The structural transformations of carbon nanosprings in the form of spiral macromolecules derived from planar coronene and kekulene molecules(graphene helicoids and spiral nanoribbons)are analyzed using molecular dynamics simulations.The interatomic interactions are described by a force field including valence bonds,bond angles,torsional and dihedral angles,as well as van derWaals interactions.While the tension/compression of such nanosprings has been analyzed in the literature,this study investigates other modes of deformation,including bending and twisting.Depending on the geometric characteristics of the carbon nanosprings,the formation of structural and helix reversal topological defects is described.During these structural transformations of the nanosprings,only van der Waals bonds break and recover,but breaking or recovery of covalent bonds does not take place.It is found that nanosprings demonstrate a significantly higher coefficient of axial thermal expansion than many metals and alloys.Under axial compression,Euler instability leads to lateral bending with continuous deformation of the nanospring axis at relatively low compression,while at high compression,bending kinks form.Various types of topological defects form on the instantly released nanospring during its relaxation from a highly stretched configuration.These results are useful for the development of nanosensors operating over a wide temperature range. 展开更多
关键词 Carbon nanospring graphene helicoid spiral nanoribbon chiral structure bending TWISTING topological defect thermal expansion molecular dynamics
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REFINED BOHR INEQUALITIES AND A REFINED BOHR-ROGOSINSKI INEQUALITY ON COMPLEX BANACH SPACES
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作者 Molla Basir AHAMED Sabir AHAMMED Hidetaka HAMADA 《Acta Mathematica Scientia》 2026年第1期19-38,共20页
In this paper,we first establish refined versions of the Bohr inequalities for the class of holomorphic functions from the unit ball BX of a complex Banach space X into ℂ.As applications,we will establish refined Bohr... In this paper,we first establish refined versions of the Bohr inequalities for the class of holomorphic functions from the unit ball BX of a complex Banach space X into ℂ.As applications,we will establish refined Bohr inequalities of functional type or of norm type for holomorphic mappings with lacunary series on the unit ball BX with values in higher dimensional spaces.Next,we obtain the Bohr-Rogosinski inequality for the class of holomorphic functions on BX.In addition,we establish an improved version of the Bohr inequality for holomorphic functions on BX.All the results are proved to be sharp. 展开更多
关键词 Banach spaces Bohr inequality Bohr-Rogosinski inequality homogeneous polynomial expansion Lacunary series
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Experimental investigation on trigger dynamics of molten droplet under external disturbance pressure during fuel-coolant interaction
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作者 He-Lin Chen Cheng Peng +2 位作者 Xian-Pin Meng Jian Deng Jiang Wu 《Nuclear Science and Techniques》 2026年第3期189-207,共19页
Fuel-coolant interaction(FCI)remains one of the most complex challenges in severe accident research,with the triggering process being a key aspect that may govern subsequent fine fragmentation and potential steam expl... Fuel-coolant interaction(FCI)remains one of the most complex challenges in severe accident research,with the triggering process being a key aspect that may govern subsequent fine fragmentation and potential steam explosions.In this study,the evolution characteristics of droplet-water interactions under external disturbance conditions were investigated using a self-designed FCI experimental setup.The experimental observations revealed that cavity formation reduced the drag force on the droplet,thereby increasing its peak velocity.However,the external disturbance pressure can disrupt the cavity,leading to a reduction in the droplet peak velocity.Furthermore,it was found that an increase in external disturbance pressure tended to increase the peak value of the droplet expansion rate,thereby promoting the fine-fragmentation process.This effect holds regardless of the initial droplet temperature,coolant temperature,or even when using droplet materials such as lead,which is generally considered unfavorable for steam explosions.Comparative analyses indicated that a higher external disturbance pressure may shorten the triggering time of the droplet surface and enhance the trigger intensity.These findings provide important phenomenological insights for further investigation of the triggering mechanisms in the initial stage of fuel-coolant interactions. 展开更多
关键词 External disturbance pressure Molten droplet Transit velocity Expansion rate Fuel-coolant interaction
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Spatial morphology optimization for reconciling urban expansion with ecological integrity based on a multi-level ecological network framework
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作者 LU Jie JIAO Sheng CHEN Xingli 《Journal of Geographical Sciences》 2026年第2期399-420,共22页
Urban spatial morphology(USM)optimization is critical to balancing biodiversity conservation and sustainable urbanization.However,previous studies predominantly focused on the socio-economic efficiency and static ecol... Urban spatial morphology(USM)optimization is critical to balancing biodiversity conservation and sustainable urbanization.However,previous studies predominantly focused on the socio-economic efficiency and static ecological metrics and rarely addressed the dynamic USM optimization across spatial scales.Here,we developed a multi-level ecological network(MEN)framework to resolve the tension between urban expansion and ecological integrity.By integrating the cost-weighted distance analysis with a hierarchical network transmission mechanism,we established a cross-scale spatial optimization system,which coordinated the regional ecological corridors and local habitat patches.Comparative experiments with conventional single-scale approaches and scenario simulations using the PLUS model show that the MEN framework had superior performance in three dimensions:(1)spatial governance:the primary-level network(peri-urban natural reserves)effectively contained urban sprawl,and the secondary-level network(intra-urban green corridors)mitigated habitat fragmentation and improved the built-environment;(2)scenario robustness:the model maintained an optimal compactness-loose balance in multiple development pathways;(3)landscape metrics:patch fragmentation decreased by 18.25%,and the internal landscape richness improved by 10.66%compared to the scenario without USM optimization.The findings provide new insight to establish a hierarchical ecological optimization framework as a nature-based spatial protocol to reconcile metropolitan growth with landscape sustainability. 展开更多
关键词 urban spatial morphology ecological network multi-level coupling scenarios simulation urban expansion
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Experimental and Numerical Optimization of Prestressed Anchor Cable Support for In-Situ Large-Span Tunnel Expansion with an Energy Balance Framework
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作者 Ying Zhu Minghui Hu +5 位作者 Shengxu Wang Xiaoliang Dong Xuewen Xiao Richeng Liu Meng Wang Zheng Yuan 《Computer Modeling in Engineering & Sciences》 2026年第2期550-585,共36页
In-situ enlargement of super-large-span tunnels can intensify excavation-induced unloading in the surrounding rock,increasing deformation demand and failure risk during construction.This study combines laboratory mode... In-situ enlargement of super-large-span tunnels can intensify excavation-induced unloading in the surrounding rock,increasing deformation demand and failure risk during construction.This study combines laboratory model tests with FLAC3D simulations to evaluate the stabilizing role of prestressed anchor cables and to establish an energy-balance framework for support optimization.Comparative model tests of existing and enlarged tunnel sections,with and without anchors,show that reinforcement increases load-carrying capacity,reduces displacement,and confines damage to more localized zones.The numerical simulations reproduce displacement fields,shear-strain localization,and plastic-zone evolution with good agreement against the experimental observations.The energy framework is implemented in the in-situ simulations by quantifying unloading-related energy release in the rock mass and reinforcement work contributed by the anchors,and by introducing an energy release–reinforcement ratio as a stability indicator.Parametric analyses indicate that anchor length,spacing,and prestress influence stability in a nonlinear manner,with diminishing returns once reinforcement extends beyond the mechanically dominant deformation zone.An efficient parameter window is identified that improves deformation and yielding control while avoiding unnecessary reinforcement.The results provide an energy-consistent and design-oriented basis for prestressed anchorage selection in large-span tunnel expansion. 展开更多
关键词 Large-span tunnel anchor cable support tunnel expansion energy balance FLAC3D parameter optimization
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Dual interlayer engineering via organic-ion pillaring and electrostatic shielding in V_(2)O_(5) cathode toward accelerated Al^(3+) transport and zero-strain aluminum batteries
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作者 Han Wang Quan Ye +5 位作者 Yanli Wang Tao Ye Xingchang Zhang Yiqun Du Rongkai Kang Jianxin Zhang 《Journal of Energy Chemistry》 2026年第3期919-928,共10页
Developing advanced cathode modification strategies to address the inherent high charge density of Al^(3+) is essential for achieving high-energy-density and long-cycle-life rechargeable aluminum batteries(RABs).Herei... Developing advanced cathode modification strategies to address the inherent high charge density of Al^(3+) is essential for achieving high-energy-density and long-cycle-life rechargeable aluminum batteries(RABs).Herein,we engineer tetraethylammonium(TEA)cation intercalation as a dual-function strategy that concurrently enables interlayer distance enlargement and electrostatic shielding effects,resolving Al^(3+) polarization-induced sluggish kinetics and cathode degradation in RABs.TEA intercalation triggers exceptional V2O5 interlayer expansion from 4.37 to 13.10Å,while the modulated charge distribution generates an electrostatic shielding effect that significantly weakens the Coulombic interactions between Al^(3+) and V2O5 frameworks.This dual mechanism collectively enhances ion diffusion kinetics and suppresses lattice stress accumulation.Ex situ X-ray diffraction and transmission electron microscopy analyses confirm that the“molecular pillar effect”of TEA enables minimal and highly reversible structural deformation of the cathode(<2.0%volume change after 200 cycles),demonstrating zero-strain aluminum-storage behavior.The optimized cathode delivers a high reversible capacity of 258 mAh g^(−1) at 0.5 A g^(−1),maintains 99%capacity retention at 5.0 A g^(−1),and exhibits an ultralow capacity decay rate of 0.01%per cycle over 6000 cycles.This work opens new pathways for designing stable high-performance RAB cathodes through synergistic modulation of electronic and lattice structures. 展开更多
关键词 Rechargeable aluminum battery Intercalation strategy Interlayer distance expansion Electrostatic shielding effect Zero-strain cathode
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Beyond renewable energy targets:Understanding the land use implications of solar energy facilities in Continental Portugal
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作者 André Alves Eduardo Gomes +1 位作者 Eduarda Marques da Costa Mário Caetano 《Geography and Sustainability》 2026年第1期190-205,共16页
The growing demand for land to accommodate renewable energy infrastructure has intensified competition with biodiversity conservation, agriculture, and ecosystem services. In Portugal, electricity system decarbonisati... The growing demand for land to accommodate renewable energy infrastructure has intensified competition with biodiversity conservation, agriculture, and ecosystem services. In Portugal, electricity system decarbonisation relies heavily on utility-scale solar energy(USSE) facilities, yet the spatial extent of land transformation associated with photovoltaic development has not been systematically assessed. This study provides an assessment of the land occupancy of USSE facilities and associated land use and land cover(LULC) changes in continental Portugal over the past two decades, as well as their spatial relationship with areas designated for land and nature conservation. A geospatial database of USSE installations(≥1 MW) was developed through the integration of multiple data sources using geographic information systems(GIS). The geometric consistency of spatial features was ensured through harmonisation and validation procedures involving GIS-based corrections supported by Sentinel-2 satellite imagery. Spatial overlay analyses were conducted with multitemporal LULC datasets and with land-use planning constraints, including areas classified for nature conservation, ecological reserves, and agricultural reserves. The results indicate that USSE deployment has been predominantly located in the southern regions of Portugal, although the location of planned projects indicates a northward shift. The implementation of USSE facilities has been mainly associated with LULC changes in forest land, agricultural areas, pastures and shrubland. Spatial overlaps were observed with areas classified within the national ecological and agricultural reserves.These patterns may be indicative of growing land-use conflicts, but the extent to which these developments align with land-use planning objectives and conservation priorities requires further examination. 展开更多
关键词 Energy geography Renewable energy expansion Solar power plants Land use change Protected areas Spatial planning
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Analysis of impact mechanism of the Yangtze River Delta integration upon county-level air pollution
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作者 Dan Li Rongrong Fang +4 位作者 Yuhang Liu Cheng Tang Sanmang Wu Yalin Lei Jiaman Li 《Chinese Journal of Population,Resources and Environment》 2026年第1期77-93,共17页
The Yangtze River Delta(YRD)is one of China’s most economically dense regions with the most dynamic county-level economies.The YRD’s success in addressing air pollution at the county level directly affects the ecolo... The Yangtze River Delta(YRD)is one of China’s most economically dense regions with the most dynamic county-level economies.The YRD’s success in addressing air pollution at the county level directly affects the ecological security of the Yangtze River Economic Belt.This study utilizes panel data of 151 counties in the YRD from 2003 to 2022.It regards the expansion of members of the YRD Urban Economic Coordination Council as a quasi-natural experiment.This study analyzes the influence of regional integration on county-level air pollution using the difference-in-differences approach,the synthetic difference-in-differences methodology,and spatial econometrics.Our findings indicate that:(1)regional integration can significantly reduce air pollution at the county level;(2)the environmental impact of regional integration is heterogeneous,influenced by regional differences,administrative constraints,and industrial foundations;and(3)regional integration reduces air pollution through advancing industrial structure and technological innovation,along with spatial spillover impacts.Therefore,policymakers should attach importance to air quality governance in counties,deepen regional integration strategies,optimize industrial structures,enhance technological innovation,and strengthen collaborative environmental governance to continuously promote regional sustainable development. 展开更多
关键词 Regional integration Expansion of the Yangtze River Delta County-level air pollution Difference-in-differences methodology Spatial econometrics
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Discharge Mechanism of Fluorinated Ketjen Black Cathode Material
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作者 Liang Zhang Jiukang Teng +6 位作者 Junjie Liu Siping Tan Xiong Zhou Zhu Liao Qianqiu Tian Wenjing Yang Xueming Li 《Transactions of Tianjin University》 2026年第1期79-90,共12页
Fluorinated carbon is a prospective cathode material for lithium(Li)primary batteries,which are widely used as power sources for military applications,such as individual combat,spacecraft,and deep-sea detection.It off... Fluorinated carbon is a prospective cathode material for lithium(Li)primary batteries,which are widely used as power sources for military applications,such as individual combat,spacecraft,and deep-sea detection.It offers high gram-specific capacity but is hindered by its low intrinsic conductivity and large volume expansion.However,fluorinated Ketjen black(FKB),with enhanced conductivity and less volume expansion compared with other fluorinated analogs,has been the subject of extensive attention,with its discharge mechanism being unclear.Herein,the structural evolution and compositional changes of FKB at various depths of discharge are revealed through characterization and analysis:The three-dimensional(3D),chain-like aggregate structure of FKB has a high void ratio,which can provide a storage space for LiF formation,thereby inhibiting the volume deformation during discharge.The discharge reaction model is a synergistic mechanism of a surface uniform reaction and local structural reorganization.The surface and defect sites preferentially react with Li^(+)and the C-F bonds in the 3D,chain-like structure selectively break to form LiF.We anticipate that our study paves the way for implementing better Li/fluorinated carbon(Li/CF_(x))batteries. 展开更多
关键词 Fluorinated Ketjen black Intrinsic conductivity Suppress volume expansion Lithium/fluorinated carbon batteries
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Molecular phylogeography and population history of Saccostrea mordax based on mitochondrial DNA
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作者 Zeyu TANG Cui LI +3 位作者 Guochen ZANG Zhenqiang LIU Zongmei CUI Haiyan WANG 《Journal of Oceanology and Limnology》 2026年第1期357-371,共15页
The Saccostrea mordax Gould,1850 is a typical intertidal species,whose genetic differentiation is influenced by various factors,including geological and climatic changes.To explore the genetic structure and historical... The Saccostrea mordax Gould,1850 is a typical intertidal species,whose genetic differentiation is influenced by various factors,including geological and climatic changes.To explore the genetic structure and historical population characteristics of Saccostrea mordax,we sequenced the mitochondrial cytochrome c oxidase subunit I(COI)gene from 58 specimens sampled from four locations in the western Pacific.Additionally,103 individuals from the Persian Gulf and western Pacific(from databases)were included for phylogenetic analysis.The Bayesian Inference tree showed that all specimens were divided into two clades,i.e.,the Persian Gulf population and the western Pacific population.Spatial molecular variance analysis indicated significant genetic differentiation between the two populations,and isolation by distance analysis revealed a positive correlation between genetic differentiation and geographic distance.Neutrality tests and Bayesian Skyline Plot suggested that both populations underwent expansions during the late Pleistocene.This study revealed the population history of Saccostrea mordax and described a new lineage,Saccostrea mordax lineage D,providing a foundation for understanding oyster biodiversity formation and genetic resource conservation. 展开更多
关键词 Saccostrea mordax cytochrome c oxidase subunit I(COI) genetic structure population expansion Saccostrea mordax lineage D
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Lattice expansion in Ni_(3)ZnC_(0.7)@C weakening CO adsorption for efficient CO_(2)electroreduction
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作者 Jiangtao Yang Yunzhen Jia +3 位作者 Guang Liu Dazhong Zhong Jinping Li Qiang Zhao 《Journal of Energy Chemistry》 2026年第1期47-55,I0003,共10页
The metallic Ni catalyst suffers from strong binding with the*CO intermediate,resulting in poisoning of the catalyst surface.It is feasible to facilitate the generation of CO by alleviating the binding strength of the... The metallic Ni catalyst suffers from strong binding with the*CO intermediate,resulting in poisoning of the catalyst surface.It is feasible to facilitate the generation of CO by alleviating the binding strength of the*CO intermediate on the Ni metal surface through a lattice expansion strategy.Here,Ni_(3)ZnC_(0.7)@C with lattice expansion was synthesized by co-doping with Zn and interstitial C through high-temperature pyrolysis.Structural characterization confirms that the lattice of Ni_(3)ZnC_(0.7)expands by 5.47%compared to Ni due to the co-doping of Zn and interstitial C.The Ni_(3)ZnC_(0.7)@C possesses excellent catalytic performance with Faradaic efficiency(FE)of CO exceeding 90%over a wide potential range from−0.8 to−1.4 V versus reversible hydrogen electrode(vs.RHE)with a peak FECO of 96.6%at−1.0 V vs.RHE.In membrane electrode assembly(MEA)testing,Ni_(3)ZnC_(0.7)@C achieves a FECO of 81.4%at the industrial-level current density of 400 mA cm^(−2).In situ attenuated total reflection surface-enhanced infrared absorption spectroscopy(ATR-SEIRAS)and density functional theory(DFT)calculations reveal that the co-introduction of Zn and interstitial C in the Ni crystal can significantly promote the desorption of*CO intermediate,which facilitates the generation of CO.This study demonstrates a viable way for designing efficient transition metal catalysts for CO_(2)electroreduction through lattice strain engineering. 展开更多
关键词 Ni_(3)ZnC_(0.7)@C Interstitial C Lattice expansion Industrial current density DFT
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Recent widespread forest expansion and densification in Southwest China
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作者 Daoming Ma Yang Yu +2 位作者 Ming Gong Zhiqiang Zhang Steven A Kannenberg 《Geography and Sustainability》 2026年第1期177-189,共13页
Large-scale afforestation and forest conservation policies have been widely implemented in Southwest China over past decades.These efforts have significantly protected the remaining long-established forests in the reg... Large-scale afforestation and forest conservation policies have been widely implemented in Southwest China over past decades.These efforts have significantly protected the remaining long-established forests in the region and greatly expanded forested areas.Utilizing nearly 30 years of satellite time-series data,we reveal that the region’s enhanced carbon sequestration(3×10^(12) g·C annually)is primarily driven by crucial changes in forest structure and age,occurring alongside a nearly 120%increase in forested land area.We observe that dense forests maintain a rapid growth rate of approximately 2.5%annually for carbon sequestration in the initial years after establishment.However,this growth rate decelerates with increasing apparent forest age.Meanwhile,the densification(modeled as an increasing forest probability)rate of forests reaches its peak growth during the 10-20 year period,sustaining a high annual growth rate of about 1.8%.We also find that improvements in forest structure,particularly the increasing of forest canopy density and apparent forest age coupled with a notable reduction in forest fragmentation,are also the main driving factors for the enhanced carbon sequestration capacity.Based on these findings,we conclude that forest restoration policies in Southwest China have been successful not only in facilitating large-scale forest growth in Southwest China but,more critically,in promoting the structural maturation(e.g.,densification and reduced fragmentation)that is essential for enhancing the region’s carbon sink capacity and its resilience. 展开更多
关键词 Reforestation policy Forest expansion and densification Carbon sequestration capacity Southwest China
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