We prove the existence of solutions of the static Landau-Lifshitz equation with multi- direct effective field and with Dirichlet boundary condition,and establish the stability of the solution of Landau-Lifshitz equati...We prove the existence of solutions of the static Landau-Lifshitz equation with multi- direct effective field and with Dirichlet boundary condition,and establish the stability of the solution of Landau-Lifshitz equation with respect to time.展开更多
The perturbation method is used to study the localization of electric field distribution and the effective nonlinear response of graded composites under an external alternating-current（AC） and direct-current（DC） e...The perturbation method is used to study the localization of electric field distribution and the effective nonlinear response of graded composites under an external alternating-current（AC） and direct-current（DC） electric field E app = E 0（1 ＋ sin ωt）.The dielectric profile of the cylindrical inclusions is modeled by function ε i（r） = C k r k（r ≤ a）,where r is the radius of the cylindrical inclusion,and C k,k,a are parameters.In the dilute limit,the local potentials and the effective nonlinear responses at all harmonics are derived.Meanwhile,the general effective nonlinear responses are also derived and compared with the effective nonlinear responses at harmonics under the AC and DC external field.It is found that the effective nonlinear AC and DC responses at harmonics can be calculated by those of the general effective nonlinear of the graded composites under the external DC electric field.Moreover,the obtained local electrical fields show that the electrical field distribution in the cylindrical inclusions is controllable,and the maximum of the electric field inside the cylinder is at its center.展开更多
The analysis of the coupling mechanism of thermal-hydraulic-mechanical(THM)fields,and solid-liquidgas(SLG)phases during gas extraction process is of profound significance to explore its numerical application in the ga...The analysis of the coupling mechanism of thermal-hydraulic-mechanical(THM)fields,and solid-liquidgas(SLG)phases during gas extraction process is of profound significance to explore its numerical application in the gas occurrence regularity and its effective extraction radius.In this study,the Hudi coal mine in Qinshui basin is taken as the research area,the influencing factors of gas occurrence were analyzed,the differences in overburden load for gas pressure distribution and the factors influencing the effective extraction radius were further discussed by using the COMSOL software.The results show that the derivation of mathematical model in gas extraction shows that the process is a process the THM fields restrict each other,and the SLG phases influence each other.The longer the extraction time,the larger the influencing range of borehole,and the better the extraction effect.The larger the diameter of borehole,the larger the effective extraction radius,and the influence on gas extraction effect is smaller in the early stage and larger in the late stage.The borehole arrangement should be flexibly arranged according to the actual extraction situation.The higher the porosity,the higher the permeability,the better the gas extraction effect.The larger the overburden load of reservoir,the stronger the effective stress,which will result in the more severe the strain,and the closure of pore and fracture,which in turn will lead to the decrease of permeability and slow down the gas extraction.The relationship among extraction time,borehole diameter,negative pressure of gas extraction,permeability with effective extraction radius is exponential.This study has important theoretical and practical significance for clarifying and summarizing the gas occurrence regularity and its engineering practice.展开更多
Under the external AC and DC electric field, the effective response of nonlinear spherical coated composites, which obey the constitutive relation of electric displaeement and electric field, is investigated in the di...Under the external AC and DC electric field, the effective response of nonlinear spherical coated composites, which obey the constitutive relation of electric displaeement and electric field, is investigated in the dilute limit by using the perturbation method. The local potentials in inclusion and host regions are derived at all harmonics. Moreover, the formulae of the effective linear and nonlinear responses are given in the dilute limit.展开更多
To overcome the serious technological issues affecting lithium-sulfur(Li-S) batteries,such as sluggish sulfur redox kinetics and the detrimental shuttle effect,heterostructure engineering has been investigated as a st...To overcome the serious technological issues affecting lithium-sulfur(Li-S) batteries,such as sluggish sulfur redox kinetics and the detrimental shuttle effect,heterostructure engineering has been investigated as a strategy to effectively capture soluble lithium polysulfide intermediates and promote their conversion reaction by integrating highly polar metal oxides with catalytically active metals sulfides.However,to fully exploit the outstanding properties of heterostructure-based composites,their detailed structure and interfacial contacts should be designed rationally.Herein,optimally arranged TiO_(2)and MoS_(2)-based heterostructures(TiO_(2)@MoS_(2)) are fabricated on carbon cloth as a multifunctional interlayer to efficiently trap polysulfide intermediates and accelerate their redox kinetics.Owing to the synergistic effects between TiO_(2)and MoS_(2)and the uniform heterointerface distribution that induces the ideally oriented built-in electric field,Li-S batteries with TiO_(2)@MoS_(2)interlayers exhibit high rate capability(601 mA h g^(-1)at 5 C),good cycling stability(capacity-fade rate of 0.067% per cycle over 500 cycles at2 C),and satisfactory areal capacity(5.2 mA h cm^(-2)) under an increased sulfur loading of 5.2 mg cm^(-2).Moreover,by comparing with a MoS_(2)@TiO_(2)interlayer composed of reversely arranged heterostructures,the effect of the built-in electric field’s direction on the electrocatalytic reactions of polysulfide intermediates is thoroughly investigated for the first time.The superior electrocatalytic activities of the rationally arranged TiO_(2)@MoS_(2)interlayer demonstrate the importance of optimizing the built-in electric field of heterostructures for producing high-performance Li-S batteries.展开更多
A robust spontaneous exchange bias effect after zero-field cooling was observed in Co_(2)Sn_(1-x)Cr_(x)O_(4)system,which was driven by the transition from superspin-glass to superferromagnetic domain embedded in the f...A robust spontaneous exchange bias effect after zero-field cooling was observed in Co_(2)Sn_(1-x)Cr_(x)O_(4)system,which was driven by the transition from superspin-glass to superferromagnetic domain embedded in the ferrimagnetic matrix.Additionally,the exchange bias effect is gradually pronounced with the positive increase in the cooling field,known as the conventional exchange bias effect.However,as the cooling field gradually decreases and transits from positive to negative,the exchange bias effect can robustly remain positive in the low-negative-field region until the cooling field increases to be sufficiently large in the negative direction.展开更多
A full-scale research study was conducted during the bored tunnelling of the Klang Valley Mass Rapid Transit-Putrajaya Line beneath an existing building structure in Kuala Lumpur,Malaysia.The primary objective was to ...A full-scale research study was conducted during the bored tunnelling of the Klang Valley Mass Rapid Transit-Putrajaya Line beneath an existing building structure in Kuala Lumpur,Malaysia.The primary objective was to investigate the tunnel-soil-pile interaction at various stages of tunnel excavation.This study combined field measurements and three-dimensional(3D)numerical analysis to understand the transient effects of TBM tunnelling on a loaded pile.An experimental pile was instrumented with vibrating wire strain gauges,an inclinometer,and distributed fibre optic sensors using Brillouin optical time domain analysis.The pile was pre-loaded and continuously monitored in real-time throughout the tunnel construction process.The 3D finite element modelling was used to simulate the pile’s transient responses based on actual tunnel boring machine(TBM)driving data.The study revealed that the zone of influence due to tunnelling effects extended from y¼2D to y¼4D,with the peak effect observed at y¼1D to 1.5D,where D represents the tunnel diameter.The analysis of axial load patterns highlighted transient responses,including tensile loads below the tunnel invert,which propagated upward and subsided due to negative skin friction.The maximum downdrag load observed reached 56%e71%of the pile’s working load.Additionally,pile movement patterns indicated outward deflections as the TBM approached and a return toward the tunnel post-passage,aligning with the predicted behaviour in a negative face loss scenario.This validated numerical framework provides a solid foundation for further parametric studies and enhances the understanding of tunnel-soil-pile interactions.展开更多
Light alloys have irreplaceable advantages such as high specific strength and low density.They are indispensable structural materials in aerospace,military,and marine engineering.It is an enduring research hotspot to ...Light alloys have irreplaceable advantages such as high specific strength and low density.They are indispensable structural materials in aerospace,military,and marine engineering.It is an enduring research hotspot to prepare high-strength and high-toughness light alloys to play a more significant role in advanced engineering applications.As a new method to improve the mechanical properties of light alloys,the magnetic field-assisted process can produce magnetoplastic effects.Therefore,in this paper,research progress on the magnetoplastic effects of light alloys assisted by magnetic fields was reviewed,and the effects of magnetic fields on dislocations,grain refinement,precipitation kinetics,phase transformation,and mechanical properties of light alloys were elucidated.Magnetic field treatment transforms radical pairs from the ground state to the excited state,which reduces the resistance between dislocations and obstacles,facilitating dislocation depinning.Moreover,magnetic field can promote grain refinement and phase transformation,increase precipitation kinetics,and synergistically improve strength and elongation.Finally,the prospects of magnetic field-assisted processes of light alloys were discussed.展开更多
The development of modern engineering components and equipment features large size,intricate shape and long service life,which places greater demands on valid methods for fatigue performance analysis.Achieving a smoot...The development of modern engineering components and equipment features large size,intricate shape and long service life,which places greater demands on valid methods for fatigue performance analysis.Achieving a smooth transformation between small-scale laboratory specimens’fatigue properties and full-scale engineering components’fatigue strength has been a long-term challenge.In this work,two dominant factors impeding the smooth transformation—notch and size effect were experimentally studied,in which fatigue tests on Al 7075-T6511(a very high-strength aviation alloy)notched specimens of different scales were carried out.Fractography analyses identified the evidence of the size effect on notch fatigue damage evolution.Accordingly,the Energy Field Intensity(EFI)initially developed for multiaxial notch fatigue analysis was improved by utilizing the volume ratio of the Effective Damage Zones(EDZs)for size effect correction.In particular,it was extended to a probabilistic model considering the inherent variability of the fatigue phenomenon.The experimental data of Al 7075-T6511 notched specimens and the model-predicted results were compared,indicating the high potential of the proposed approach in fatigue evaluation under combined notch and size effects.展开更多
Solvated zinc ions are prone to undergo desolvation at the electrode/electrolyte interfaces,and unstable H_(2)O molecules within the solvated sheaths tend to trigger hydrogen evolution reaction(HER),further accelerati...Solvated zinc ions are prone to undergo desolvation at the electrode/electrolyte interfaces,and unstable H_(2)O molecules within the solvated sheaths tend to trigger hydrogen evolution reaction(HER),further accelerating interfaces decay.Herein,we propose for the first time a novel strategy to enhance the interfacial stabilities by insitu dynamic reconstruction of weakly solvated Zn2þduring the desolvation processes at heterointerfaces.Theoretical calculations indicate that,due to built-in electric field effects(BEFs),the plating/stripping mechanism shifts from[Zn(H_(2)O)_(6)]_(2)þto[Zn(H_(2)O)_(5)(SO_(4))^(2-)]_(2)þwithout additional electrolyte additives,reducing the solvation ability of H_(2)O,enhancing the competitive coordination of SO_(4)^(2-),essentially eliminating the undesirable side effects of anodes.Hence,symmetric cells can operate stably for 3000 h(51.7-times increase in cycle life),and the full cells can operate stably for 5000 cycles(51.5-times increase in cycle life).This study provides valuable insights into the critical design of weakly solvated Zn^(2+) þand desolvation processes at heterointerfaces.展开更多
The future space-borne gravitational wave(GW)detectors would provide a promising probe for the new physics beyond the standard model that admits the first-order phase transitions.The predictions for the GW background ...The future space-borne gravitational wave(GW)detectors would provide a promising probe for the new physics beyond the standard model that admits the first-order phase transitions.The predictions for the GW background vary sensitively among different concrete particle physics models but also share a large degeneracy in the model buildings,which motivates an effective model description on the phase transition based on different patterns of the electroweak symmetry breaking(EWSB).In this paper,using the scalar N-plet model as a demonstration,we propose an effective classification for three different patterns of EWSB:(1)radiative symmetry breaking with classical scale invariance,(2)the Higgs mechanism in a generic scalar extension,and(3)higher-dimensional operators.We conclude that a strong first-order phase transition could be realized for(1)and(2)with a small quartic coupling and a small isospin of an additional N-plet field for the light scalar field model with and without the classical scale invariance,and(3)with a large mixing coupling between scalar fields and a large isospin of the N-plet field for the heavy scalar field model.展开更多
We study the Nc scalings of pion-nucleon and nucleon-nucleon scatterings in hadron effective field theory.By assuming Witten's counting rules are applied to matrix elements or scattering amplitudes, which use the ...We study the Nc scalings of pion-nucleon and nucleon-nucleon scatterings in hadron effective field theory.By assuming Witten's counting rules are applied to matrix elements or scattering amplitudes, which use the relativistic normalization for the nucleons, we find that the nucleon axial coupling gAis of order N_c^0, and a consistent large Nc counting can be established for the pion-nucleon and nucleon-nucleon scatterings. We also justify the nonperturbative treatment of the low energy nucleon-nucleon interaction with the large N_c analysis and find that the deuteron binding energy is of order 1/N_c.展开更多
This study presents an experimental investigation of the coupled caloric effect driven by dual-fields in metamagnetic alloy ErCo_(2) with strong magneto-structural coupling.Magnetic measurements were conducted under d...This study presents an experimental investigation of the coupled caloric effect driven by dual-fields in metamagnetic alloy ErCo_(2) with strong magneto-structural coupling.Magnetic measurements were conducted under different pressures,revealing that the application of hydrostatic pressure stabilizes a small volume of paramagnetism(PM) phase,resulting in a shift of the phase transition temperature towards the low-temperature region.This shift is opposite to the temperature associated with the magnetic field-driven phase transition.As pressure increases,the metamagnetic transition in ErCo_(2) is suppressed,and the hysteresis disappears.However,the produced cross-coupling caloric effect compensates the decrease in entropy change caused by the disappearance of the metamagnetic transition.As a result,a reversible giant magnetocaloric effect of 46.2 J/(kg·K) without hysteresis is achieved at a pressure of 0.910 GPa.Moreover,we propose that the temperature span of ErCo_(2) can be significantly widened by optimizing the thermodynamic pathway of the magnetic and pressure fields,overcoming the defect of a narrow temperature range.展开更多
Amplification-free,highly sensitive,and specific nucleic acid detection is crucial for health monitoring and diagnosis.The type III CRISPR-Cas10 system,which provides viral immunity through CRISPRassociated protein ef...Amplification-free,highly sensitive,and specific nucleic acid detection is crucial for health monitoring and diagnosis.The type III CRISPR-Cas10 system,which provides viral immunity through CRISPRassociated protein effectors,enables a new amplification-free nucleic acid diagnostic tool.In this study,we develop a CRISPR-graphene field-effect transistors(GFETs)biosensor by combining the type III CRISPR-Cas10 system with GFETs for direct nucleic acid detection.This biosensor exploits the target RNA-activated continuous ss DNA cleavage activity of the d Csm3 CRISPR-Cas10 effector and the high charge density of a hairpin DNA reporter on the GFET channel to achieve label-free,amplification-free,highly sensitive,and specific RNA detection.The CRISPR-GFET biosensor exhibits excellent performance in detecting medium-length RNAs and miRNAs,with detection limits at the aM level and a broad linear range of 10^(-15)to 10^(-11)M for RNAs and 10^(-15)to 10^(-9)M for miRNAs.It shows high sensitivity in throat swabs and serum samples,distinguishing between healthy individuals(N=5)and breast cancer patients(N=6)without the need for extraction,purification,or amplification.This platform mitigates risks associated with nucleic acid amplification and cross-contamination,making it a versatile and scalable diagnostic tool for molecular diagnostics in human health.展开更多
Flexible transparent antennas(FTAs)are widely used in wireless transmission fields,and their technological iterations are accelerating.However,the high losses caused by materials and structures limit the development o...Flexible transparent antennas(FTAs)are widely used in wireless transmission fields,and their technological iterations are accelerating.However,the high losses caused by materials and structures limit the development of FTAs with both high light transmission and high gain,and the rapid iteration rate demands greater process flexibility,which makes it difficult for existing technologies to achieve both demands.Here,we design a novel shell-core structure composite metal mesh(CMM)FTA to achieve extremely low skin depth loss and ohmic loss using skin effect and report a novel hybrid additive manufacturing method based on electric field oriented deposition to achieve efficient and flexible manufacturing of the unique Ag/Cu core-shell structure CMM FTA.The typical sample has a light transmittance of 80%(including substrate)when the sheet resistance is 0.29Ω·sq^(-1),and has excellent bending and torsion resistance.The peak gain in the working band is as high as 5.22 dB,and the efficiency is 80%,which is close to the performance of the opaque Cu patch antenna.It also realizes smooth and stable real-time wireless transmission under bending and long-distance conditions.This method addresses the shortcomings of FTAs,namely their high cost,low manufacturing efficiency,and low performance,especially in the rapid iterative development of antennas.展开更多
A sensor,serving as a transducer,produces a quantifiable output in response to a predetermined input stimulus,which may be of a chemical or physical nature.The field of gas detection has experienced a substantial surg...A sensor,serving as a transducer,produces a quantifiable output in response to a predetermined input stimulus,which may be of a chemical or physical nature.The field of gas detection has experienced a substantial surge in research activity,attributable to the diverse functionalities and enhanced accessibility of advanced active materials.In this work,recent advances in gas sensors,specifically those utilizing Field Effect Transistors(FETs),are summarized,including device configurations,response characteristics,sensor materials,and application domains.In pursuing high-performance artificial olfactory systems,the evolution of FET gas sensors necessitates their synchronization with material advancements.These materials should have large surface areas to enhance gas adsorption,efficient conversion of gas input to detectable signals,and strong mechanical qualities.The exploration of gas-sensitive materials has covered diverse categories,such as organic semiconductor polymers,conductive organic compounds and polymers,metal oxides,metal-organic frameworks,and low-dimensional materials.The application of gas sensing technology holds significant promise in domains such as industrial safety,environmental monitoring,and medical diagnostics.This comprehensive review thoroughly examines recent progress,identifies prevailing technical challenges,and outlines prospects for gas detection technology utilizing field effect transistors.The primary aim is to provide a valuable reference for driving the development of the next generation of gas-sensitive monitoring and detection systems characterized by improved sensitivity,selectivity,and intelligence.展开更多
With the acceleration of industrialization and urbanization,ammonia nitrogen pollution in water bodies has become increasingly severe,making the development of efficient and low-consumption wastewater treatment tech-n...With the acceleration of industrialization and urbanization,ammonia nitrogen pollution in water bodies has become increasingly severe,making the development of efficient and low-consumption wastewater treatment tech-nologies highly significant.This study employs three-dimensional computational fluid dynamics(CFD)to investigate the cavitation mechanisms and flow field characteristics in a novel jet impingement-negative pressure ammonia removal reactor.The simulation,validated by experimental pressure data with a high degree of consistency,utilizes the Mixture model,the Realizable k-εturbulence model,and the Schnerr-Sauer cavitation model.The results demonstrate that the flow velocity undergoes a substantial acceleration within the orifice nozzle,triggering a dramatic pressure drop from an inlet value of approximately 1.17 MPa to below the saturated vapor pressure,reaching as low as−109 kPa,which induces intense cavitation.Cavitation bubbles primarily originate on the inner wall of the nozzle,with the vapor volume fraction peaking at about 0.42 within the orifice.A strong positive correlation was observed between the local vapor fraction and the flow velocity,indicating that cavitation enhances jet intensity.Furthermore,vortex structures near the wall and within the jacket sustain low-pressure zones,facilitating continuous cavitation and efficient mixing.This study quantitatively elucidates the cavitation dynamics and its interplay with the flow field,providing a solid theoretical and numerical basis for optimizing the reactor design to enhance ammonia removal efficiency.展开更多
Recently, Shiet al. [2008 Phys. Left. A 372 5922] have studied the dynamical response of the kinetic Ising model in the presence of a sinusoidal oscillating field and presented the dynamic phase diagrams by using an e...Recently, Shiet al. [2008 Phys. Left. A 372 5922] have studied the dynamical response of the kinetic Ising model in the presence of a sinusoidal oscillating field and presented the dynamic phase diagrams by using an effective-field theory （EFT） and a mean-field theory （MFT）. The MFT results are in conflict with those of the earlier work of Tome and de Oliveira, [1990 Phys. Rev. A 41 4251]. We calculate the dynamic phase diagrams and find that our results are similar to those of the earlier work of Tome and de Oliveira; hence the dynamic phase diagrams calculated by Shiet al. are incomplete within both theories, except the low values of frequencies for the MFT calculation. We also investigate the influence of external field frequency （w） and static external field amplitude （h0） for both MFT and EFT calculations. We find that the behaviour of the system strongly depends on the values of w and h0.展开更多
Rechargeable magnesium batteries(RMBs)are considered promising candidates for next-generation energy storage systems due to their high theoretical capacity.However,the non-uniform deposition/stripping behavior of Mg m...Rechargeable magnesium batteries(RMBs)are considered promising candidates for next-generation energy storage systems due to their high theoretical capacity.However,the non-uniform deposition/stripping behavior of Mg metal hinders the practical application of RMBs.This study demonstrates that the designed interfacial electric field effect,driven by a copper phthalocyanine(CuPc)conductive interlayer,enhances the kinetics and stability of the Mg anode.In situ electrochemical impedance spectroscopy coupled with distribution of relaxation times analysis reveals that the highly delocalized electron cloud network of CuPc establishes a low-energy-barrier electron transport pathway,significantly reducing charge transfer resistance.Electrochemical characterization and density functional theory calculations indicate that the interfacial electric field effect effectively improves interfacial Mg^(2+)diffusion by enhancing electron delocalization and reducing the Mg^(2+)migration energy barrier.Furthermore,finite element simulations substantiate that the interfacial electric field imparts uniform interfacial charge distribution and homogeneous Mg deposition during plating/stripping processes.Consequently,the symmetric cell with CuPc@Mg achieves an ultra-long lifetime(1,400h at 5mAcm^(−2))and a high Coulombic efficiency(99.3%).Furthermore,the CuPc@Mg||Mo6S8 cell achieves high capacity retention(92%).This work highlights the potential of metal phthalocyanines in stabilizing Mg anodes.展开更多
Electrocaloric effect(ECE)of ferroelectrics has attracted considerable interest due to its potential application in environmentally friendly solid-state refrigeration.The discovery of giant ECE in ferroelectric thin f...Electrocaloric effect(ECE)of ferroelectrics has attracted considerable interest due to its potential application in environmentally friendly solid-state refrigeration.The discovery of giant ECE in ferroelectric thin films has greatly renewed the research activities and significantly stimulated experimental and theoretical investigations.In this review,the recent progress on the theoretical modeling of ECE in ferroelectric and antiferroelectric materials are introduced,which mainly focuses on the phase field modeling and first-principles based effective Hamiltonian method.We firstly provide the theoretical foundation and technique details for each method.Then a comprehensive review on the progress in the application of two methods and the strategies to tune the ECE are presented.Finally,we outline the practical procedure on the development of multi-scale computational method without experiemtal parameters for the screening of optimized electrocaloric materials.展开更多
文摘We prove the existence of solutions of the static Landau-Lifshitz equation with multi- direct effective field and with Dirichlet boundary condition,and establish the stability of the solution of Landau-Lifshitz equation with respect to time.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.40876094 and JQ10974106)the National High Technology Research and Development Program of China(Grant Nos.2009AA09Z102 and 2008AA09A403)+1 种基金the Excellent Youth Fundation of Shandong Scientific Committee,China(Grant No.JQ201018)the Natural Science Foundation of Shandong Province,China(Grant No.ZR2009AZ002)
文摘The perturbation method is used to study the localization of electric field distribution and the effective nonlinear response of graded composites under an external alternating-current（AC） and direct-current（DC） electric field E app = E 0（1 ＋ sin ωt）.The dielectric profile of the cylindrical inclusions is modeled by function ε i（r） = C k r k（r ≤ a）,where r is the radius of the cylindrical inclusion,and C k,k,a are parameters.In the dilute limit,the local potentials and the effective nonlinear responses at all harmonics are derived.Meanwhile,the general effective nonlinear responses are also derived and compared with the effective nonlinear responses at harmonics under the AC and DC external field.It is found that the effective nonlinear AC and DC responses at harmonics can be calculated by those of the general effective nonlinear of the graded composites under the external DC electric field.Moreover,the obtained local electrical fields show that the electrical field distribution in the cylindrical inclusions is controllable,and the maximum of the electric field inside the cylinder is at its center.
基金financially supported by the University Synergy Innovation Program of Anhui Province(No.GXXT-2021-018)the National Natural Science Foundation of China(No.42102217)+3 种基金the Natural Science Research Project of Anhui University(Nos.KJ2020A0315,KJ2020A0317)the Institute of Energy,Hefei Comprehensive National Science Center(No.21KZS218)the Natural Science Foundation of Anhui Province(No.2108085MD134)the Foundation of State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum,Beijing(No.PRP/open-2005)
文摘The analysis of the coupling mechanism of thermal-hydraulic-mechanical(THM)fields,and solid-liquidgas(SLG)phases during gas extraction process is of profound significance to explore its numerical application in the gas occurrence regularity and its effective extraction radius.In this study,the Hudi coal mine in Qinshui basin is taken as the research area,the influencing factors of gas occurrence were analyzed,the differences in overburden load for gas pressure distribution and the factors influencing the effective extraction radius were further discussed by using the COMSOL software.The results show that the derivation of mathematical model in gas extraction shows that the process is a process the THM fields restrict each other,and the SLG phases influence each other.The longer the extraction time,the larger the influencing range of borehole,and the better the extraction effect.The larger the diameter of borehole,the larger the effective extraction radius,and the influence on gas extraction effect is smaller in the early stage and larger in the late stage.The borehole arrangement should be flexibly arranged according to the actual extraction situation.The higher the porosity,the higher the permeability,the better the gas extraction effect.The larger the overburden load of reservoir,the stronger the effective stress,which will result in the more severe the strain,and the closure of pore and fracture,which in turn will lead to the decrease of permeability and slow down the gas extraction.The relationship among extraction time,borehole diameter,negative pressure of gas extraction,permeability with effective extraction radius is exponential.This study has important theoretical and practical significance for clarifying and summarizing the gas occurrence regularity and its engineering practice.
文摘Under the external AC and DC electric field, the effective response of nonlinear spherical coated composites, which obey the constitutive relation of electric displaeement and electric field, is investigated in the dilute limit by using the perturbation method. The local potentials in inclusion and host regions are derived at all harmonics. Moreover, the formulae of the effective linear and nonlinear responses are given in the dilute limit.
基金supported by the National R&D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2018M3D1A1058793 and 2021R1A3B1068920)supported by the Creative Materials Discovery Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2018M3D1A1058744)the Yonsei Signature Research Cluster Program of 2021 (2021-22-0002)。
文摘To overcome the serious technological issues affecting lithium-sulfur(Li-S) batteries,such as sluggish sulfur redox kinetics and the detrimental shuttle effect,heterostructure engineering has been investigated as a strategy to effectively capture soluble lithium polysulfide intermediates and promote their conversion reaction by integrating highly polar metal oxides with catalytically active metals sulfides.However,to fully exploit the outstanding properties of heterostructure-based composites,their detailed structure and interfacial contacts should be designed rationally.Herein,optimally arranged TiO_(2)and MoS_(2)-based heterostructures(TiO_(2)@MoS_(2)) are fabricated on carbon cloth as a multifunctional interlayer to efficiently trap polysulfide intermediates and accelerate their redox kinetics.Owing to the synergistic effects between TiO_(2)and MoS_(2)and the uniform heterointerface distribution that induces the ideally oriented built-in electric field,Li-S batteries with TiO_(2)@MoS_(2)interlayers exhibit high rate capability(601 mA h g^(-1)at 5 C),good cycling stability(capacity-fade rate of 0.067% per cycle over 500 cycles at2 C),and satisfactory areal capacity(5.2 mA h cm^(-2)) under an increased sulfur loading of 5.2 mg cm^(-2).Moreover,by comparing with a MoS_(2)@TiO_(2)interlayer composed of reversely arranged heterostructures,the effect of the built-in electric field’s direction on the electrocatalytic reactions of polysulfide intermediates is thoroughly investigated for the first time.The superior electrocatalytic activities of the rationally arranged TiO_(2)@MoS_(2)interlayer demonstrate the importance of optimizing the built-in electric field of heterostructures for producing high-performance Li-S batteries.
基金financially supported by the National Natural Science Foundation of China(Nos.11474111 and 11604281)the Young Elite Scientists Sponsorship Program by CAST(No.YESS20220618)the Hundreds of Talents program of Sun Yat-sen University(No.210192)
文摘A robust spontaneous exchange bias effect after zero-field cooling was observed in Co_(2)Sn_(1-x)Cr_(x)O_(4)system,which was driven by the transition from superspin-glass to superferromagnetic domain embedded in the ferrimagnetic matrix.Additionally,the exchange bias effect is gradually pronounced with the positive increase in the cooling field,known as the conventional exchange bias effect.However,as the cooling field gradually decreases and transits from positive to negative,the exchange bias effect can robustly remain positive in the low-negative-field region until the cooling field increases to be sufficiently large in the negative direction.
文摘A full-scale research study was conducted during the bored tunnelling of the Klang Valley Mass Rapid Transit-Putrajaya Line beneath an existing building structure in Kuala Lumpur,Malaysia.The primary objective was to investigate the tunnel-soil-pile interaction at various stages of tunnel excavation.This study combined field measurements and three-dimensional(3D)numerical analysis to understand the transient effects of TBM tunnelling on a loaded pile.An experimental pile was instrumented with vibrating wire strain gauges,an inclinometer,and distributed fibre optic sensors using Brillouin optical time domain analysis.The pile was pre-loaded and continuously monitored in real-time throughout the tunnel construction process.The 3D finite element modelling was used to simulate the pile’s transient responses based on actual tunnel boring machine(TBM)driving data.The study revealed that the zone of influence due to tunnelling effects extended from y¼2D to y¼4D,with the peak effect observed at y¼1D to 1.5D,where D represents the tunnel diameter.The analysis of axial load patterns highlighted transient responses,including tensile loads below the tunnel invert,which propagated upward and subsided due to negative skin friction.The maximum downdrag load observed reached 56%e71%of the pile’s working load.Additionally,pile movement patterns indicated outward deflections as the TBM approached and a return toward the tunnel post-passage,aligning with the predicted behaviour in a negative face loss scenario.This validated numerical framework provides a solid foundation for further parametric studies and enhances the understanding of tunnel-soil-pile interactions.
基金supported by the National Natural Science Foundation of China(No.52274382)the National Key Research and Development Program of China(No.2023YFB3407000).
文摘Light alloys have irreplaceable advantages such as high specific strength and low density.They are indispensable structural materials in aerospace,military,and marine engineering.It is an enduring research hotspot to prepare high-strength and high-toughness light alloys to play a more significant role in advanced engineering applications.As a new method to improve the mechanical properties of light alloys,the magnetic field-assisted process can produce magnetoplastic effects.Therefore,in this paper,research progress on the magnetoplastic effects of light alloys assisted by magnetic fields was reviewed,and the effects of magnetic fields on dislocations,grain refinement,precipitation kinetics,phase transformation,and mechanical properties of light alloys were elucidated.Magnetic field treatment transforms radical pairs from the ground state to the excited state,which reduces the resistance between dislocations and obstacles,facilitating dislocation depinning.Moreover,magnetic field can promote grain refinement and phase transformation,increase precipitation kinetics,and synergistically improve strength and elongation.Finally,the prospects of magnetic field-assisted processes of light alloys were discussed.
基金support from the Key Program of the National Natural Science Foundation of China(No.12232004)the Training Program of the Sichuan Province Science and the Technology Innovation Seedling Project(No.MZGC20230012)are acknowledged.
文摘The development of modern engineering components and equipment features large size,intricate shape and long service life,which places greater demands on valid methods for fatigue performance analysis.Achieving a smooth transformation between small-scale laboratory specimens’fatigue properties and full-scale engineering components’fatigue strength has been a long-term challenge.In this work,two dominant factors impeding the smooth transformation—notch and size effect were experimentally studied,in which fatigue tests on Al 7075-T6511(a very high-strength aviation alloy)notched specimens of different scales were carried out.Fractography analyses identified the evidence of the size effect on notch fatigue damage evolution.Accordingly,the Energy Field Intensity(EFI)initially developed for multiaxial notch fatigue analysis was improved by utilizing the volume ratio of the Effective Damage Zones(EDZs)for size effect correction.In particular,it was extended to a probabilistic model considering the inherent variability of the fatigue phenomenon.The experimental data of Al 7075-T6511 notched specimens and the model-predicted results were compared,indicating the high potential of the proposed approach in fatigue evaluation under combined notch and size effects.
基金financially supported by the National Natural Science Foundation of China(51977097).
文摘Solvated zinc ions are prone to undergo desolvation at the electrode/electrolyte interfaces,and unstable H_(2)O molecules within the solvated sheaths tend to trigger hydrogen evolution reaction(HER),further accelerating interfaces decay.Herein,we propose for the first time a novel strategy to enhance the interfacial stabilities by insitu dynamic reconstruction of weakly solvated Zn2þduring the desolvation processes at heterointerfaces.Theoretical calculations indicate that,due to built-in electric field effects(BEFs),the plating/stripping mechanism shifts from[Zn(H_(2)O)_(6)]_(2)þto[Zn(H_(2)O)_(5)(SO_(4))^(2-)]_(2)þwithout additional electrolyte additives,reducing the solvation ability of H_(2)O,enhancing the competitive coordination of SO_(4)^(2-),essentially eliminating the undesirable side effects of anodes.Hence,symmetric cells can operate stably for 3000 h(51.7-times increase in cycle life),and the full cells can operate stably for 5000 cycles(51.5-times increase in cycle life).This study provides valuable insights into the critical design of weakly solvated Zn^(2+) þand desolvation processes at heterointerfaces.
基金supported by the National Key Research and Development Program of China under Grant Nos.2021YFC2203004,2021YFA0718304,2020YFC2201501RGC is supported by the National Natural Science Foundation of China under Grants Nos.11947302,11991052,11690022,11821505 and 11851302+8 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(CAS)under Grant Nos.XDB23030100 and XDA15020701the Key Research Program of the CAS under Grant No.XDPB15the Key Research Program of Frontier Sciences of CAS.SJW is supported by the National Key Research and Development Program of China under Grant Nos.2021YFC2203004 and 2021YFA0718304the National Natural Science Foundation of China under Grant Nos.12422502 and 12105344the China Manned Space Project under Grant No.CMS-CSST-2021-B01JHY is supported by the National Science Foundation of China under Grant Nos.12022514,11875003 and 12047503the National Key Research and Development Program of China under Grant Nos.2020YFC2201501 and 2021YFA0718304the CAS Project for Young Scientists in Basic Research under Grant No.YSBR-006the Key Research Program of the CAS under Grant No.XDPB15.
文摘The future space-borne gravitational wave(GW)detectors would provide a promising probe for the new physics beyond the standard model that admits the first-order phase transitions.The predictions for the GW background vary sensitively among different concrete particle physics models but also share a large degeneracy in the model buildings,which motivates an effective model description on the phase transition based on different patterns of the electroweak symmetry breaking(EWSB).In this paper,using the scalar N-plet model as a demonstration,we propose an effective classification for three different patterns of EWSB:(1)radiative symmetry breaking with classical scale invariance,(2)the Higgs mechanism in a generic scalar extension,and(3)higher-dimensional operators.We conclude that a strong first-order phase transition could be realized for(1)and(2)with a small quartic coupling and a small isospin of an additional N-plet field for the light scalar field model with and without the classical scale invariance,and(3)with a large mixing coupling between scalar fields and a large isospin of the N-plet field for the heavy scalar field model.
基金Supported by the National Natural Science Foundation of China under Grant No.11305137
文摘We study the Nc scalings of pion-nucleon and nucleon-nucleon scatterings in hadron effective field theory.By assuming Witten's counting rules are applied to matrix elements or scattering amplitudes, which use the relativistic normalization for the nucleons, we find that the nucleon axial coupling gAis of order N_c^0, and a consistent large Nc counting can be established for the pion-nucleon and nucleon-nucleon scatterings. We also justify the nonperturbative treatment of the low energy nucleon-nucleon interaction with the large N_c analysis and find that the deuteron binding energy is of order 1/N_c.
基金supported by the National Key R&D Program of China (2021YFB3501202,2021YFB3501204,2019YFA0704900,2020YFA0711500,2023YFA1406003,2022YFB3505201)the National Natural Science Foundation of China (52088101,U23A20550,92263202,22361132534)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB33030200)。
文摘This study presents an experimental investigation of the coupled caloric effect driven by dual-fields in metamagnetic alloy ErCo_(2) with strong magneto-structural coupling.Magnetic measurements were conducted under different pressures,revealing that the application of hydrostatic pressure stabilizes a small volume of paramagnetism(PM) phase,resulting in a shift of the phase transition temperature towards the low-temperature region.This shift is opposite to the temperature associated with the magnetic field-driven phase transition.As pressure increases,the metamagnetic transition in ErCo_(2) is suppressed,and the hysteresis disappears.However,the produced cross-coupling caloric effect compensates the decrease in entropy change caused by the disappearance of the metamagnetic transition.As a result,a reversible giant magnetocaloric effect of 46.2 J/(kg·K) without hysteresis is achieved at a pressure of 0.910 GPa.Moreover,we propose that the temperature span of ErCo_(2) can be significantly widened by optimizing the thermodynamic pathway of the magnetic and pressure fields,overcoming the defect of a narrow temperature range.
基金financially supported by the National Science and Technology Innovation 2030 Grants(2021ZD0201600)the National Key R&D Program of China(2021YFA0717000)+2 种基金the Intramural Joint Program Fund of State Key Laboratory of Microbial Technology(Project No.SKLMTIJP-2024-05)the Natural Science Foundation of Qingdao-Original exploration project(Project No.24-4-4-zrjj-139-jch)the National Natural Science Foundation of China(31771380)。
文摘Amplification-free,highly sensitive,and specific nucleic acid detection is crucial for health monitoring and diagnosis.The type III CRISPR-Cas10 system,which provides viral immunity through CRISPRassociated protein effectors,enables a new amplification-free nucleic acid diagnostic tool.In this study,we develop a CRISPR-graphene field-effect transistors(GFETs)biosensor by combining the type III CRISPR-Cas10 system with GFETs for direct nucleic acid detection.This biosensor exploits the target RNA-activated continuous ss DNA cleavage activity of the d Csm3 CRISPR-Cas10 effector and the high charge density of a hairpin DNA reporter on the GFET channel to achieve label-free,amplification-free,highly sensitive,and specific RNA detection.The CRISPR-GFET biosensor exhibits excellent performance in detecting medium-length RNAs and miRNAs,with detection limits at the aM level and a broad linear range of 10^(-15)to 10^(-11)M for RNAs and 10^(-15)to 10^(-9)M for miRNAs.It shows high sensitivity in throat swabs and serum samples,distinguishing between healthy individuals(N=5)and breast cancer patients(N=6)without the need for extraction,purification,or amplification.This platform mitigates risks associated with nucleic acid amplification and cross-contamination,making it a versatile and scalable diagnostic tool for molecular diagnostics in human health.
基金supported by the National Natural Science Foundation of China(Grant Nos.52375348 and 52175331)the Natural Science Foundation of Shandong Province,China(Grant Nos.ZR2020ZD04 and ZR2022ME014).
文摘Flexible transparent antennas(FTAs)are widely used in wireless transmission fields,and their technological iterations are accelerating.However,the high losses caused by materials and structures limit the development of FTAs with both high light transmission and high gain,and the rapid iteration rate demands greater process flexibility,which makes it difficult for existing technologies to achieve both demands.Here,we design a novel shell-core structure composite metal mesh(CMM)FTA to achieve extremely low skin depth loss and ohmic loss using skin effect and report a novel hybrid additive manufacturing method based on electric field oriented deposition to achieve efficient and flexible manufacturing of the unique Ag/Cu core-shell structure CMM FTA.The typical sample has a light transmittance of 80%(including substrate)when the sheet resistance is 0.29Ω·sq^(-1),and has excellent bending and torsion resistance.The peak gain in the working band is as high as 5.22 dB,and the efficiency is 80%,which is close to the performance of the opaque Cu patch antenna.It also realizes smooth and stable real-time wireless transmission under bending and long-distance conditions.This method addresses the shortcomings of FTAs,namely their high cost,low manufacturing efficiency,and low performance,especially in the rapid iterative development of antennas.
基金supported by the National Key R&D Program of China(No.2023YFC3707201)the National Natural Science Foundation of China(No.52320105003)+2 种基金the Informatization Plan of Chinese Academy of Sciences(No.CAS-WX2023PY-0103)the Fundamental Research Funds for the Central Universities(No.E3ET1803)sponsored by the Alliance of International Science Organizations(ANSO)scholarship for young talents.
文摘A sensor,serving as a transducer,produces a quantifiable output in response to a predetermined input stimulus,which may be of a chemical or physical nature.The field of gas detection has experienced a substantial surge in research activity,attributable to the diverse functionalities and enhanced accessibility of advanced active materials.In this work,recent advances in gas sensors,specifically those utilizing Field Effect Transistors(FETs),are summarized,including device configurations,response characteristics,sensor materials,and application domains.In pursuing high-performance artificial olfactory systems,the evolution of FET gas sensors necessitates their synchronization with material advancements.These materials should have large surface areas to enhance gas adsorption,efficient conversion of gas input to detectable signals,and strong mechanical qualities.The exploration of gas-sensitive materials has covered diverse categories,such as organic semiconductor polymers,conductive organic compounds and polymers,metal oxides,metal-organic frameworks,and low-dimensional materials.The application of gas sensing technology holds significant promise in domains such as industrial safety,environmental monitoring,and medical diagnostics.This comprehensive review thoroughly examines recent progress,identifies prevailing technical challenges,and outlines prospects for gas detection technology utilizing field effect transistors.The primary aim is to provide a valuable reference for driving the development of the next generation of gas-sensitive monitoring and detection systems characterized by improved sensitivity,selectivity,and intelligence.
基金supported by Chongqing Natural Science Foundation Innovation and Development Joint Fund(CSTB2023NSCQ-LZX0095)Chongqing Natural Science Foundation General Project(CSTB2025NSCQ-GPX0955)+3 种基金Science and Technology Research Program of Chongqing Municipal Education Commission of China(KJQN202401157)The Open and Innovation Fund of Hubei Three Gorges Laboratory(SK250005)The Key Laboratory of Manufacturing and Application of Intelligent Well Control for Oil and Gas Production and Transportation of Luzhou(2024LZOGB-05)postgraduate Innovation Project of Chongqing University of Technology(CYS240709).
文摘With the acceleration of industrialization and urbanization,ammonia nitrogen pollution in water bodies has become increasingly severe,making the development of efficient and low-consumption wastewater treatment tech-nologies highly significant.This study employs three-dimensional computational fluid dynamics(CFD)to investigate the cavitation mechanisms and flow field characteristics in a novel jet impingement-negative pressure ammonia removal reactor.The simulation,validated by experimental pressure data with a high degree of consistency,utilizes the Mixture model,the Realizable k-εturbulence model,and the Schnerr-Sauer cavitation model.The results demonstrate that the flow velocity undergoes a substantial acceleration within the orifice nozzle,triggering a dramatic pressure drop from an inlet value of approximately 1.17 MPa to below the saturated vapor pressure,reaching as low as−109 kPa,which induces intense cavitation.Cavitation bubbles primarily originate on the inner wall of the nozzle,with the vapor volume fraction peaking at about 0.42 within the orifice.A strong positive correlation was observed between the local vapor fraction and the flow velocity,indicating that cavitation enhances jet intensity.Furthermore,vortex structures near the wall and within the jacket sustain low-pressure zones,facilitating continuous cavitation and efficient mixing.This study quantitatively elucidates the cavitation dynamics and its interplay with the flow field,providing a solid theoretical and numerical basis for optimizing the reactor design to enhance ammonia removal efficiency.
基金Project supported by the Scientific and Technological Research Council of Turkey (TBTAK) (Grant No. 107T533)the Erciyes University Research Funds (Grant Nos. FBA-06-01 and FBD-08-593)
文摘Recently, Shiet al. [2008 Phys. Left. A 372 5922] have studied the dynamical response of the kinetic Ising model in the presence of a sinusoidal oscillating field and presented the dynamic phase diagrams by using an effective-field theory （EFT） and a mean-field theory （MFT）. The MFT results are in conflict with those of the earlier work of Tome and de Oliveira, [1990 Phys. Rev. A 41 4251]. We calculate the dynamic phase diagrams and find that our results are similar to those of the earlier work of Tome and de Oliveira; hence the dynamic phase diagrams calculated by Shiet al. are incomplete within both theories, except the low values of frequencies for the MFT calculation. We also investigate the influence of external field frequency （w） and static external field amplitude （h0） for both MFT and EFT calculations. We find that the behaviour of the system strongly depends on the values of w and h0.
基金financially supported by the National Natural Science Foundation of China(52274295)Hebei Province Science and Technology Research and Development Platform Special Innovation Capability Enhancement Plan Project(24464402D)+3 种基金the Fundamental Research Funds for the Central Universities(N2423051,N2423005)the Science and Technology Project of Hebei Education Department(QN2024238)The Basic Research Program Project of Shijiazhuang City for Universities Stationed in Hebei Province(241790937A)2025 Hebei Provincial Post-graduate Student Innovation Ability Training Funding Project(CXZZBS2025202,CXZZSS2025157).
文摘Rechargeable magnesium batteries(RMBs)are considered promising candidates for next-generation energy storage systems due to their high theoretical capacity.However,the non-uniform deposition/stripping behavior of Mg metal hinders the practical application of RMBs.This study demonstrates that the designed interfacial electric field effect,driven by a copper phthalocyanine(CuPc)conductive interlayer,enhances the kinetics and stability of the Mg anode.In situ electrochemical impedance spectroscopy coupled with distribution of relaxation times analysis reveals that the highly delocalized electron cloud network of CuPc establishes a low-energy-barrier electron transport pathway,significantly reducing charge transfer resistance.Electrochemical characterization and density functional theory calculations indicate that the interfacial electric field effect effectively improves interfacial Mg^(2+)diffusion by enhancing electron delocalization and reducing the Mg^(2+)migration energy barrier.Furthermore,finite element simulations substantiate that the interfacial electric field imparts uniform interfacial charge distribution and homogeneous Mg deposition during plating/stripping processes.Consequently,the symmetric cell with CuPc@Mg achieves an ultra-long lifetime(1,400h at 5mAcm^(−2))and a high Coulombic efficiency(99.3%).Furthermore,the CuPc@Mg||Mo6S8 cell achieves high capacity retention(92%).This work highlights the potential of metal phthalocyanines in stabilizing Mg anodes.
基金the financial support from the National Natural Science Foundation of China(Grant No.11972320)Zhejiang Provincial Natural Science Foundation(Grant No.LZ17A020001).
文摘Electrocaloric effect(ECE)of ferroelectrics has attracted considerable interest due to its potential application in environmentally friendly solid-state refrigeration.The discovery of giant ECE in ferroelectric thin films has greatly renewed the research activities and significantly stimulated experimental and theoretical investigations.In this review,the recent progress on the theoretical modeling of ECE in ferroelectric and antiferroelectric materials are introduced,which mainly focuses on the phase field modeling and first-principles based effective Hamiltonian method.We firstly provide the theoretical foundation and technique details for each method.Then a comprehensive review on the progress in the application of two methods and the strategies to tune the ECE are presented.Finally,we outline the practical procedure on the development of multi-scale computational method without experiemtal parameters for the screening of optimized electrocaloric materials.
