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Dual-regulation of pore confinement and mouth size for enhanced sodium storage in hard carbon
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作者 Zhiyuan Liu Xin Wang +4 位作者 Xuan Xie Yue Li Hui Peng Guofu Ma Ziqiang Lei 《Journal of Energy Chemistry》 2026年第1期1-12,I0002,共13页
Hard carbon(HC)remains a leading anode candidate for sodium-ion storage,yet its application is hindered by low initial Coulombic efficiency(ICE)and limited plateau capacity due to uncontrolled defect density and open ... Hard carbon(HC)remains a leading anode candidate for sodium-ion storage,yet its application is hindered by low initial Coulombic efficiency(ICE)and limited plateau capacity due to uncontrolled defect density and open porosity.Here,we propose a scalable dual-regulation strategy that simultaneously tunes pore mouth size and defect chemistry to enhance sodium storage performance.Using phenol-formaldehyde resin as the carbon precursor and phosphorus pentoxide(P_(2)O_(5))as a bifunctional sacrificial template and dopant source,we synthesize phosphorus-functionalized hard carbon(PF-PHC)featuring a high density of closed pores with well-confined sub-nanometer pore entrances.The in-situ sublimation of P_(2)O_(5) during pyrolysis promotes the formation of closed-pore architectures,while residual phosphorus atoms effectively passivate vacancy-type defects,thereby reducing irreversible Na+adsorption and mitigating excessive solid electrolyte interphase(SEI)formation.As a result,PF-PHC achieves an ICE of 89.3%and a plateau capacity of 289 mAh g^(−1).In-situ characterizations reveal that regulating pore mouth dimensions decouples Na+and solvent access,enabling highly selective ion transport and stable interfacial chemistry.Sodium-ion hybrid capacitors(SIHCs)assembled based on PF-PHC deliver exceptional rate performance and outstanding long-term cycling stability,retaining 98.2%after 10,000 cycles at 2 A g^(−1).This study establishes pore mouth engineering as a robust and scalable design principle for advancing next-generation HC-based sodium storage materials. 展开更多
关键词 Hard carbon Pore mouth regulation Pore confinement Sodium-ion storage
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Suppression of ablative Rayleigh–Taylor instability by spatially modulated laser in inertial confinement fusion
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作者 Zhantao Lu Xinglong Xie +10 位作者 Xiao Liang Meizhi Sun Ping Zhu Xuejie Zhang Chunqing Xing Linjun Li Hao Xue Guoli Zhang Rashid Ul Haq Dongjun Zhang Jianqiang Zhu 《Matter and Radiation at Extremes》 2026年第1期29-38,共10页
The suppression of ablative Rayleigh–Taylor instability(ARTI)by a spatially modulated laser in inertial confinement fusion(ICF)is studied through numerical simulations.The results show that in the acceleration phase ... The suppression of ablative Rayleigh–Taylor instability(ARTI)by a spatially modulated laser in inertial confinement fusion(ICF)is studied through numerical simulations.The results show that in the acceleration phase of ICF implosion,the growth of ARTI can be suppressed by using a short-wavelength spatially modulated laser.The ARTI growth rate decreases as the wavelength of the spatially modulated laser decreases,and ARTI is completely suppressed after a certain wavelength has been reached.A spatially uniform laser is introduced to keep the state of motion of the implosion fluid consistent,and it is found that the proportion of the spatially modulated laser required for complete suppression of ARTI decreases as the wavelength continues to decrease.We also optimize the spatial intensity distribution of the spatially modulated laser.In addition,as the duration of the spatially modulated laser decreases,the proportion required for completely suppressing ARTI increases,but the required energy decreases.When the perturbation wavenumber decreases,the wavelength of the spatially modulated laser required for complete suppression of ARTI becomes longer.In the case of multimode perturbation,ARTI can also be significantly suppressed by a spatially modulated laser,and the perturbation amplitude can be reduced to less than 10% of that without a spatially modulated laser.We believe that the conclusions drawn from our simulations can provide the basis for new approaches to control ARTI in ICF. 展开更多
关键词 ablative Rayleigh Taylor instability ablative rayleigh taylor instability arti numerical simulationsthe spatially modulated laser inertial confinement fusion icf spatially modulated laserthe acceleration phase spatially uniform
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Size matters:quantum confinement-driven dynamics in CsPbI_(3)quantum dot light-emitting diodes 被引量:1
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作者 Shuo Li Wenxu Yin +1 位作者 Weitao Zheng Xiaoyu Zhang 《Journal of Semiconductors》 2025年第4期55-61,共7页
The quantum confinement effect fundamentally alters the optical and electronic properties of quantum dots(QDs),making them versatile building blocks for next-generation light-emitting diodes(LEDs).This study investiga... The quantum confinement effect fundamentally alters the optical and electronic properties of quantum dots(QDs),making them versatile building blocks for next-generation light-emitting diodes(LEDs).This study investigates how quantum confinement governs the charge transport,exciton dynamics,and emission efficiency in QD-LEDs,using CsPbI_(3) QDs as a model system.By systematically varying QD sizes,we reveal size-dependent trade-offs in LED performance,such as enhanced efficiency for smaller QDs but increased brightness and stability for larger QDs under high current densities.Our findings offer critical insights into the design of high-performance QD-LEDs,paving the way for scalable and energy-efficient optoelectronic devices. 展开更多
关键词 quantum confinement effect CsPbI_(3) quantum dot light-emitting diode
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Improved equation of state model for the phase behavior of CO_(2)-hydrocarbon coupling nanopore confinements 被引量:1
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作者 Yuan Zhang Zijing Niu +1 位作者 Fangfang Yang Zhanwei Ma 《Natural Gas Industry B》 2025年第3期316-327,共12页
In shale reservoirs,fluids are often confined within nanopores,leading to apparent effects on the properties and phase behavior of the fluid.However,previous studies have primarily focused on the effect of capillary p... In shale reservoirs,fluids are often confined within nanopores,leading to apparent effects on the properties and phase behavior of the fluid.However,previous studies have primarily focused on the effect of capillary pressure or adsorption on well performance,and only a very limited number of studies have researched the complex and coupled impact of confinement on capillarity,adsorption,and interactions between fluid molecules and pore walls.Therefore,in this study,an effective method is developed for evaluating the coupled effects of nanopore confinement on CO_(2) injection performance.First,a comprehensive thermodynamic model that incorporates adsorption,capillary pressure,and molecule-wall interaction in nanopores by modifying the Peng-Robinson equation of state(PR-EOS)is proposed.Subsequently,the calculated critical properties of different components are validated against experimental measured data,illustrating that the developed model can accurately predict the properties of the components of CO_(2)-hydrocarbon systems.Numerical simulations of field-scale case studies were then performed and calibrated using a modified phase equilibrium model.Typical fluid properties were inputted to investigate the effect of nanopore confinement on the CO_(2) injection performance.The results of this study show that the ultimate recovery factor increases by approximately 4.61%at a pore size of 10 nm,indicating that nanopore confinement is advantageous to well performance.Light hydrocarbons undergo more intense mass transfer than heavy hydrocarbons.Furthermore,as the pore radius decreased from 100 nm to 10 nm,the CO_(2) storage coefficient increased by 2.8%.The findings of this study deepen the collective understanding of the effect of nanopore confinement on CO_(2) displacement and storage,which has significant field-scale applications. 展开更多
关键词 Nanopore confinement Minimum miscibility pressure Shale formations CO_(2)injection
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Hydrodynamic instability growth of the fuel-ablator interface induced by rippled rarefaction waves in inertial confinement fusion implosion experiments
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作者 Zheng Yan Zhu Chen +6 位作者 Jiwei Li Lifeng Wang Zhiyuan Li Chao Zhang Fengjun Ge Junfeng Wu Weiyan Zhang 《Matter and Radiation at Extremes》 2025年第5期84-93,共10页
Hydrodynamic instability growth at the deuterium-tritium(DT)fuel-ablator interface plays a critical role in determining the performance of inertial confinement fusion implosions.During the late stages of implosion,ins... Hydrodynamic instability growth at the deuterium-tritium(DT)fuel-ablator interface plays a critical role in determining the performance of inertial confinement fusion implosions.During the late stages of implosion,insufficient doping of the ablator material can result in highenergy X-ray preheat,which may trigger the development of a classical-like Rayleigh-Taylor instability(RTI)at the fuel-ablator interface.In implosion experiments at the Shenguang 100 kJ-level laser facility,the primary source of perturbation is the roughness of the inner DT ice interface.In this study,we propose an analytical model to describe the feed-out process of the initial roughness of the inner DT ice interface.The perturbation amplitude derived from this model serves as the initial seed for the late-time RTI during the acceleration phase.Our findings confirm the presence of classical-like RTI at the fuel-ablator interface.Numerical simulations conducted using a radiation hydrodynamic code validate the proposed analytical model and demonstrate the existence of a peak mode number in both the feed-out process and the classical-like RTI.It provides an alternative bridge between the current target fabrication limitations and the unexpected implosion performance. 展开更多
关键词 inertial confinement fusion fuel ablator interface Rayleigh Taylor instability hydrodynamic instability radiation hydrodynamic code numerical simulations rippled rarefaction waves performance inertial confinement fusion implosionsduring
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Anti-Swelling Polyelectrolyte Hydrogel with Submillimeter Lateral Confinement for Osmotic Energy Conversion
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作者 Yongxu Liu Jiangnan Song +10 位作者 Zhen Liu Jialin Chen Dejuan Wang Hui Zhi Jiebin Tang Yafang Zhang Ningbo Li Weijia Zhou Meng An Hong Liu Guobin Xue 《Nano-Micro Letters》 2025年第4期96-110,共15页
Harvesting the immense and renewable osmotic energy with reverse electrodialysis(RED)technology shows great promise in dealing with the ever-growing energy crisis.One key challenge is to improve the output power densi... Harvesting the immense and renewable osmotic energy with reverse electrodialysis(RED)technology shows great promise in dealing with the ever-growing energy crisis.One key challenge is to improve the output power density with improved trade-off between membrane permeability and selectivity.Herein,polyelectrolyte hydrogels(channel width,2.2 nm)with inherent high ion conductivity have been demonstrated to enable excellent selective ion transfer when confined in cylindrical anodized aluminum pore with lateral size even up to the submillimeter scale(radius,0.1 mm).The membrane permeability of the anti-swelling hydrogel can also be further increased with cellulose nanofibers.With real seawater and river water,the output power density of a three-chamber cell on behalf of repeat unit of RED system can reach up to 8.99 W m^(-2)(per unit total membrane area),much better than state-of-the-art membranes.This work provides a new strategy for the preparation of polyelectrolyte hydrogel-based ion-selective membranes,owning broad application prospects in the fields of osmotic energy collection,electrodialysis,flow battery and so on. 展开更多
关键词 Ionic polymer HYDROGEL confinement effect Anti-swelling Osmotic energy conversion
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Improving CO_(2) solubility in a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide/mesoporous titanium dioxide/water with confinement effect
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作者 Haoran Yin Lili Mu +3 位作者 Yifeng Chen Licheng Li Kang Sun Xiaoyan Ji 《Chinese Journal of Chemical Engineering》 2025年第4期100-109,共10页
Confinement effect is an effective method to enhance carbon dioxide(CO_(2))solubility.In this study,a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([Hmim][NTf_2])/mesoporous titanium ... Confinement effect is an effective method to enhance carbon dioxide(CO_(2))solubility.In this study,a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([Hmim][NTf_2])/mesoporous titanium dioxide(M-TiO_(2))/water(H_2O)was developed,and its confinement effect was regulated by changing the pore structure of M-TiO_(2).CO_(2) solubility in the hybrid sorbent was measured experimentally,and the thermodynamic properties including Henry's constant and desorption enthalpy were calculated.Furthermore,the confinement effect in the hybrid sorbent was quantified.Additionally,the hybrid sorbent was recycled with a multi-cycle experiment.The results showed that M-TiO_(2) calcined at 773.2 K(MT500)could lead to an efficient confinement effect.CO_(2) solubility in the hybrid sorbent increased by 49.8%compared to that of H_2O when the mass fraction of[Hmim][NTf_2]/MT500 was 5.0%(mass),where the contribution of confinement effect on Gibbs free energy occupied 5.2%. 展开更多
关键词 Ionic liquid Carbon dioxide Mesoporous titanium dioxide confinement effect Thermodynamics
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Interfacial Frustration-induced Novel Self-assembled Structures from Block Copolymers under Janus Spherical Confinement
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作者 Xing-Ye Li Zheng Wang +2 位作者 Yu-Hua Yin Run Jiang Bao-Hui Li 《Chinese Journal of Polymer Science》 2025年第8期1423-1432,共10页
Spatial confinement of block copolymers can induce frustrations,which can further be utilized to regulate self-assembled structures,thus providing an efficient route for fabricating novel structures.We studied the sel... Spatial confinement of block copolymers can induce frustrations,which can further be utilized to regulate self-assembled structures,thus providing an efficient route for fabricating novel structures.We studied the self-assembly of AB di-block copolymers(di-BCPs)confined in Janus spherical nanocavities using simulations,and explained the structure formation mechanisms.In the case of a strongly selective cavity wall,all the lamella-forming,gyroid-forming,and cylinder-forming di-BCPs can form interfacial frustration-induced Janus concentric perforated lamellar nanoparticles,whose outermost is a Janus spherical shell and the internal is a sphere with concentric perforated lamellar structure.In particular,Janus concentric perforated lamellar nanoparticles with holes distributed only near the equatorial plane were obtained in both lamella-forming and gyroid-forming di-BCPs,directly reflecting the effect of interfacial frustration.The minority-block domain of the cylider-forming di-BCPs may form hemispherical perforated lamellar structures with holes distributed in parallel layers with a specific orientation.For symmetric di-BCPs,both the A and B domains in each nanoparticle are continuous,interchangeable,and have rotational symmetry.While for gyroid-forming and cylinder-forming di-BCPs,only the majority-block domains are continuous in each nanoparticle,and holes in the minority-block domains usually have rotational symmetry.In the case of a weakly selective cavity wall,the inhomogeneity of the cavity wall results in structures having a specific orientation(such as flower-like and branched structures in gyroid-forming and cylinder-forming di-BCPs)and a perforated wetting layer with uniformly distributed holes.The novel nanoparticles obtained may have potential applications in nanotechnology as functional nanostructures or nanoparticles. 展开更多
关键词 Simulated annealing Diblock copolymer SELF-ASSEMBLY 3D confinement Interfacial frustration
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Production and magnetic self-confinement of e^(-)e^(+)plasma by an extremely intense laser pulse incident on a structured solid target
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作者 Alexander Samsonov Alexander Pukhov 《Matter and Radiation at Extremes》 2025年第5期10-19,共10页
We propose an all-optical,single-laser-pulse scheme for generating a dense relativistic strongly magnetized electron-positron pair plasma.The scheme involves the interaction of an extremely intense(I■10^(24) W/cm^(2)... We propose an all-optical,single-laser-pulse scheme for generating a dense relativistic strongly magnetized electron-positron pair plasma.The scheme involves the interaction of an extremely intense(I■10^(24) W/cm^(2))circularly polarized laser pulse with a solid-density target containing a conical cavity.Through full-scale three-dimensional particle-in-cell simulations that account for quantum electrodynamic effects,it is shown that this interaction results in two significant outcomes:first,the generation of quasi-static magnetic fields reaching tens of gigagauss,and,second,the production of large quantities of electron-positron pairs(up to 10^(13))via the Breit-Wheeler process.The e^(-)e^(+)plasma becomes trapped in the magnetic field and remains confined in a small volume for hundreds of femtoseconds,far exceeding the laser timescale.The dependence of pair plasma parameters,as well as the efficiency of plasma production and confinement,is discussed in relation to the properties of the laser pulse and the target.Realizing this scheme experimentally would enable the investigation of physical processes relevant to extreme astrophysical environments. 展开更多
关键词 polarized laser pulse intense laser pulse structured solid target quantum electrodynamic effects generation magnetic confinement electron positron plasma Breit Wheeler process
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Spatial confinement of free-standing graphene sponge enables excellent stability of conversion-type Fe_(2)O_(3) anode for sodium storage
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作者 Jun Dong Senyuan Tan +7 位作者 Sunbin Yang Yalong Jiang Ruxing Wang Jian Ao Zilun Chen Chaohai Zhang Qinyou An Xiaoxing Zhang 《Chinese Chemical Letters》 2025年第3期544-549,共6页
Conversion-type anode materials are highly desirable for Na-ion batteries(NIBs)due to their high theoretical capacity.Nevertheless,the active materials undergo severe expansion and pulverization during the sodiation,r... Conversion-type anode materials are highly desirable for Na-ion batteries(NIBs)due to their high theoretical capacity.Nevertheless,the active materials undergo severe expansion and pulverization during the sodiation,resulting in inferior cycling stability.Herein,a self-supporting three-dimensional(3D)graphene sponge decorated with Fe_(2)O_(3)nanocubes(rGO@Fe_(2)O_(3))is constructed.Specifically,the 3D graphene sponge with resilience and high porosity benefits to accommodate the volume expansion of the Fe_(2)O_(3)nanocubes and facilitates the rapid electrons/ions transport,enabling spatial confinement to achieve outstanding results.Besides,the free-standing rGO@Fe_(2)O_(3)can be directly used as an electrode without additional binders and conductive additives,which helps to obtain a higher energy density.Based on the total mass of the rGO@Fe_(2)O_(3)material,the rGO@Fe_(2)O_(3)anode presents a specific capacity of 859 mAh/g at 0.1 A/g.It also delivers an impressive cycling performance(327 mAh/g after 2000 cycles at 1 A/g)and a superior rate capacity(162mAh/g at 20 A/g).The coin-type Na_(3)V_(2)(PO_(4))_(3)@C//rGO@Fe_(2)O_(3)NIB exhibits an energy density of 265.3Wh/kg.This unique 3D ionic/electronic conductive network may provide new strategies to design advanced conversion-type anode materials for high-performance NIBs. 展开更多
关键词 Conversion-type anode Spatial confinement Fe_(2)O_(3) Graphene network SELF-SUPPORTING Sodium-ion batteries
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Effect of laser wavelength on growth of ablative Rayleigh–Taylor instability in inertial confinement fusion
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作者 Zhantao Lu Xinglong Xie +9 位作者 Xiao Liang Meizhi Sun Ping Zhu Xuejie Zhang Linjun Li Hao Xue Guoli Zhang Rashid Ul Haq Dongjun Zhang Jianqiang Zhu 《Matter and Radiation at Extremes》 2025年第2期71-79,共9页
The effect of drive laser wavelength on the growth of ablative Rayleigh–Taylor instability(ARTI)in inertial confinemen fusion(ICF)is studied with two-dimensional numerical simulations.The results show that in the pla... The effect of drive laser wavelength on the growth of ablative Rayleigh–Taylor instability(ARTI)in inertial confinemen fusion(ICF)is studied with two-dimensional numerical simulations.The results show that in the plasma acceleration phase,shorter wavelengths lead to more efficien coupling between the laser and the kinetic energy of the implosion fluid Under the condition that the laser energy coupled to the implosion flui is constant,the ARTI growth rate decreases as the laser wavelength moves toward the extreme ultraviolet band,reaching its minimum value near λ=65 nm,and when the laser wavelength continuously moves toward the X-ray band,the ARTI growth rate increases rapidly.It is found that the results deviate from the theoretical ARTI growth rate.As the laser intensity benchmark increases,the position of the minimum ARTI growth rate shifts toward shorter wavelengths.As the initial sinusoidal perturbation wavenumber decreases,the position of the minimum ARTI growth rate shifts toward longer wavelengths.We believe that the conclusions drawn from the present simulations and analysis will help provide a better understanding of the ICF process and improve the theory of ARTI growth. 展开更多
关键词 ablative rayleigh taylor instability arti inertial confinemen fusion icf inertial confinement fusion implosion flui laser wavelength implosion fluid ablative Rayleigh Taylor instability plasma acceleration
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Effect of the confinement on two-dimensional complex plasmas with the shear force
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作者 Haoyu Qi Yang Liu +3 位作者 Shaohuang Bian Runing Liang Dan Zhang Feng Huang 《Chinese Physics B》 2025年第10期459-464,共6页
Langevin molecular dynamics simulations reveal the impact of confinement strength on the structure and dynamics of a two-dimensional complex plasma under constant shear force.Structural analysis via Voronoi diagrams a... Langevin molecular dynamics simulations reveal the impact of confinement strength on the structure and dynamics of a two-dimensional complex plasma under constant shear force.Structural analysis via Voronoi diagrams and the local bond-order parameter|Ψ6|shows that stronger confinement enhances hexagonal order and mitigates shear-induced disorder.Dynamical properties,determined by mean-square displacement(MSD)and the velocity autocorrelation function(VACF),indicate that the shear-induced superdiffusion weakens with increasing confinement strength.The entropy change(?S)shows that strong confinement(ω>1)balances particle dynamics between shear and shear-free regions,thereby stabilizing the system.These findings highlight the interplay between confinement and shear force. 展开更多
关键词 complex plasmas steady shear flow Langevin dynamics simulation confinement
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Dynamics of Charged Ring Polymers under Gel Confinement
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作者 Lu-Jie Huo Kai-Ru Qu +1 位作者 Zhen-Zhong Yang Di Jia 《Chinese Journal of Polymer Science》 2025年第3期399-405,共7页
Ring polymers are ubiquitous in various fields including biomaterials,drug release and gene therapy.All of these applications involve the dynamics and diffusion process of ring polymers in a confined environment.By us... Ring polymers are ubiquitous in various fields including biomaterials,drug release and gene therapy.All of these applications involve the dynamics and diffusion process of ring polymers in a confined environment.By using dynamic light scattering(DLS),we discovered a dynamical transition for charged ring polymers with increasing ring concentration in the gel matrix from a diffusive state to a non-diffusive topological frustrated state with a more compact conformation.When the ring polymer size is smaller than the mesh size of the gel matrix,the rings are diffusive at low concentration of 5 g/L.The ring diffusion coefficient in the gel matrix is an order of magnitude smaller than that of rings in solution,obeying the Ogston's model.At high ring concentration of 40 g/L,the collective dynamical behavior of the charged rings exhibits a topologically frustrated non-diffusive state,which may originate from the inter-ring threading with the external confinement from the gel matrix.Based on our previous theoretical work,we also conjectured that in such a non-diffusive state,the ring polymers might adopt a more compact conformation with the overall size exponentν=1/3. 展开更多
关键词 Charged ring polymer Dynamics under confinement Non-diffusive topologically frustrated dynamics Dynamic light scattering Collective diffusion coefficient
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β-Cyclodextrin inducing confinement effect enabling spherical Na_(3)V_(2)(PO_(4))_(3)with multielectron reaction and superior performance at extreme conditions for sodium-ion batteries
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作者 Shuming Zhang Tao Zhou +1 位作者 Hongen Shi Yanjun Chen 《Journal of Energy Chemistry》 2025年第9期138-153,I0006,共17页
Currently,simultaneous regulation of external morphology and internal electronic structure for Na_(3)V_(2)(PO_(4))_(3)(NVP)is rarely realized.Herein,complexes of β-cyclodextrin(βCD)and ethylenediaminetetraacetic aci... Currently,simultaneous regulation of external morphology and internal electronic structure for Na_(3)V_(2)(PO_(4))_(3)(NVP)is rarely realized.Herein,complexes of β-cyclodextrin(βCD)and ethylenediaminetetraacetic acid ferric sodium salt(EDTAFeNa)are utilized for the one-step preparation of NVP with spherical morphology as well as Fe substitution.βCD is initially hydrolyzed into glucose,and then carbon microspheres with numerous pores are formed through continuous dehydration and carbonization.The intermediate hydroxymethylfurfural is rich in active functional groups,which are attractive for the V/P-contained raw materials.Accordingly,the nucleation sites for NVP are successfully limited in the spherical framework,possessing a superior surface area of 97.15 g m^(-2).Furthermore,the beneficial Fe in EDTAFeNa enters into the NVP bulk to construct a novel Fe-doped Na_(3)V_(1.95)Fe_(0.05)(PO_(4))_(3)(NVP/β-ISC)material.Fe-substitution induces significant optimizations of electronic structure for NVP,which has been verified by the newly generated abundant oxygen vacancies and extended V-O bond length.Moreover,a multielectron reaction is activated,resulting from the V^(4+)/V^(5+)redox couple.The charge compensation mechanism of NVP/β-ISC is also deeply investigated.Density functional theory(DFT)calculations theoretically elaborate the mechanism of Fe-doping.Consequently,NVP/β-ISC reveals superior sodium storage performance in both half and full cells and even at different extreme conditions(needling,soaking,bending,and freezing). 展开更多
关键词 b-Cyclodextrin Spherical morphology confinement effect Multielectron reaction Na_(3)V_(2)(PO_(4))_(3)
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Flows and mass transport in confinement
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作者 Yanbo Xie 《Acta Mechanica Sinica》 2025年第8期1-3,共3页
Flows and transport phenomena in confined spaces have emerged as a key direction in modern fluid dynamics research[1].Scaling down the hydrodynamic length of a system does not simply lead to a laminar flow in low Reyn... Flows and transport phenomena in confined spaces have emerged as a key direction in modern fluid dynamics research[1].Scaling down the hydrodynamic length of a system does not simply lead to a laminar flow in low Reynolds number,but reveals plenty of new phenomena with novel technological implications.Unlike in macroscale systems,fluid behavior at micro-and nanoscales is governed by forces that act at or near the interfaces,including surface tension,wettability,van der Waals interactions,and electrostatic effects,etc.These interfacial forces produce new hydrodynamics and mass transport phenomena that have not been observed on large scales,which are widely used in multidisciplinary areas. 展开更多
关键词 electrostatic eff confined spaces MICROSCALE flows transport phenomena HYDRODYNAMICS nanoscale surface tensionwettabilityvan der waals interactionsand laminar flow
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国产ECRH 175 GHz兆瓦回旋管实现500 kW/100 s长脉冲输出
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作者 胡林林 黄麒力 +11 位作者 胡鹏 卓婷婷 龚胜刚 刘皓中 向永飞 姚徐 郭俊 蒋艺 张鲁奇 孙迪敏 马国武 马弘舸 《强激光与粒子束》 北大核心 2026年第1期41-43,共3页
报道了面向磁约束聚变电子回旋共振加热(ECRH)应用的175 GHz长脉冲回旋管的最新实验进展。该回旋管输出窗采用了金刚石窗,电子枪采用双阳极磁控注入枪,谐振腔工作模式为TE_(28,11),收集极采用了单极降压和纵向扫描线圈。通过实验调试和... 报道了面向磁约束聚变电子回旋共振加热(ECRH)应用的175 GHz长脉冲回旋管的最新实验进展。该回旋管输出窗采用了金刚石窗,电子枪采用双阳极磁控注入枪,谐振腔工作模式为TE_(28,11),收集极采用了单极降压和纵向扫描线圈。通过实验调试和长时间老炼,该回旋管实现了输出功率500 kW、连续工作100 s的实验结果,总效率达到为46%。这是国内首次在ECRH回旋管研究中实现百千瓦级100 s长脉冲输出。 展开更多
关键词 回旋管 兆瓦 电子回旋共振加热 磁约束聚变
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大坝坝基深厚覆盖层承压水水力响应规律研究
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作者 窦智 史一博 +4 位作者 徐海洋 庄超 王泽君 张学羿 周志芳 《水电能源科学》 北大核心 2026年第2期150-155,58,共7页
我国西南高山峡谷河流中广泛分布着“强-弱-强”渗透性组合的深厚覆盖层,其承压含水层水力响应规律对水利工程建设和安全运行有着重要影响。引入“水力响应范围”这一概念,围绕因工程建设导致的承压含水层水力响应规律变化问题,建立了... 我国西南高山峡谷河流中广泛分布着“强-弱-强”渗透性组合的深厚覆盖层,其承压含水层水力响应规律对水利工程建设和安全运行有着重要影响。引入“水力响应范围”这一概念,围绕因工程建设导致的承压含水层水力响应规律变化问题,建立了深厚覆盖层地下水渗流三维有限元模型,定量研究了水头差、弱透水层特性(厚度、埋深和渗透系数)对承压水水力响应规律的影响。结果表明,水头差升高导致承压水水力响应范围扩大;在弱透水层厚度较小时,承压水水力响应范围对厚度变化更为敏感,而在弱透水层厚度达到一定范围后,承压水水力响应范围逐渐稳定;随着弱透水层在深厚覆盖层中埋深增大,承压水水力响应范围的临界位置逐渐向下游移动;强弱透水层渗透性差别达到10^(3)时,对承压水水力响应范围的影响最大;敏感性分析结果显示,强弱透水层渗透性差别是深厚覆盖层承压含水层水力响应范围最为敏感的因素。研究结果为相关工程的安全设计和管理提供了理论支持,对复杂水文地质条件下的地下水渗流场分析具有重要意义。 展开更多
关键词 地下水 数值模拟 承压含水层 水力响应 敏感性分析
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考虑中主应力影响的修正摩尔-库仑硬岩强度准则
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作者 俞缙 周永盛 +2 位作者 张超 常旭 蔡燕燕 《工程科学与技术》 北大核心 2026年第1期46-56,共11页
预测岩石破坏强度的关键在于建立能够准确反映复杂应力条件下岩石强度准则。首先,基于摩尔应力圆理论提出了真三轴应力条件下Mohr-Coulomb准则(M-C准则)泛函式,结合岩石真三轴试验数据进行分析,结果表明,中主应力对黏结强度分量影响显著... 预测岩石破坏强度的关键在于建立能够准确反映复杂应力条件下岩石强度准则。首先,基于摩尔应力圆理论提出了真三轴应力条件下Mohr-Coulomb准则(M-C准则)泛函式,结合岩石真三轴试验数据进行分析,结果表明,中主应力对黏结强度分量影响显著,而对摩擦强度分量的影响可忽略不计,该规律可通过中主应力效应函数进行量化表征。随后,通过分析D-P准则、Mogi准则和修正Lade准则,发现强度预测偏差大的原因在于中主应力效应函数的数学表征失准,为解决这一关键问题,引入双参数η和γ构建新型中主应力效应函数,并结合岩石临界状态特性对经典M-C准则进行修正,建立能够考虑中主应力影响的非线性M-C强度准则。最后,采用6类不同硬岩真三轴试验数据对新准则的适用性进行验证,并与4种传统强度准则进行对比分析。结果表明,修正M-C强度准则能够很好地描述中主应力效应,强度预测精度达0.94以上,证明了该准则在复杂应力状态下的适用性和工程应用价值。 展开更多
关键词 深部岩石 强度准则 中主应力 临界围压 非线性
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筑坝堆石料动力特性试验研究
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作者 李东 杜俊 +2 位作者 王孝东 张瑞 熊治茗 《水电能源科学》 北大核心 2026年第2期100-104,99,共6页
堆石料作为典型粗粒土已广泛应用于土石坝建设中,研究其动力特性对土石坝抗震安全评价具有重要意义。基于DJSZ-150大型粗粒土动静三轴试验机,开展堆石料动力特性试验,深入研究围压和固结比对土体动态参数的作用机制。试验结果表明,动模... 堆石料作为典型粗粒土已广泛应用于土石坝建设中,研究其动力特性对土石坝抗震安全评价具有重要意义。基于DJSZ-150大型粗粒土动静三轴试验机,开展堆石料动力特性试验,深入研究围压和固结比对土体动态参数的作用机制。试验结果表明,动模量随动应变增大逐渐衰减,而围压和固结比的增大均会引起动模量增大;动剪切模量比在动剪应变小于0.1%时缓慢下降,超过0.1%后快速衰减,最后趋于稳定,曲线表现出明显的归一性;阻尼比随动剪应变的增加呈非线性增长,增大固结比能显著增强堆石料的能量耗散能力。该研究揭示了应力状态对堆石料动力特性的调控机制,可为土石坝抗震设计提供理论基础。 展开更多
关键词 动三轴试验 围压 固结比 动模量 阻尼比
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