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
In this research,a series of biaxial compression and biaxial fatigue tests were conducted to investigate the mechanical behaviors of marble and sandstone under biaxial confinements.Experimental results demonstrate tha...In this research,a series of biaxial compression and biaxial fatigue tests were conducted to investigate the mechanical behaviors of marble and sandstone under biaxial confinements.Experimental results demonstrate that the biaxial compressive strength of rocks under biaxial compression increases firstly,and subsequently decreases with increase of the intermediate principal stress.The fatigue failure characteristics of the rocks in biaxial fatigue tests are functions of the peak value of fatigue loads,the intermediate principal stress and the rock lithology.With the increase of the peak values of fatigue loads,the fatigue lives of rocks decrease.The intermediate principal stress strengthens the resistance ability of rocks to fatigue loads except considering the strength increasing under biaxial confinements.The fatigue lives of rocks increase with the increase of the intermediate principal stress under the same ratio of the fatigue load and their biaxial compressive strength.The acoustic emission(AE)and fragments studies showed that the sandstone has higher ability to resist the fatigue loads compared to the marble,and the marble generated a greater number of smaller fragments after fatigue failure compared to the sandstone.So,it can be inferred that the rock breaking efficiency and rock burst is higher or severer induced by fatigue loading than that induced by monotonous quasi-static loading,especially for hard rocks.展开更多
The self-assembly of linear ABC triblock copolymers under cylindrical confinements is investigated in two- dimensional space using the real-space self-consistent field theory. The effects of confinement degrees and pr...The self-assembly of linear ABC triblock copolymers under cylindrical confinements is investigated in two- dimensional space using the real-space self-consistent field theory. The effects of confinement degrees and preferential strengths on the triblock copolymer phase behaviors with special polymer parameters are first considered. On one hand, different confinement degrees cause different phase behaviors in nanopores with the neutral surfaces. Moreover, the strongly preferential surface fields can surpass the confinement degrees and volume fractions in determing the confined phase behaviors. On the other hand, in contrast, confined morphologies are more sensitive to the variations in the A-preferential surface field strength. Subsequently, the incompatibility degrees between different blocks are systematically varied under cylindrical nanopore confinements. Under cylindrical nanopore confinements, the morphologies are very sensitive to the variations in the incompatibility degrees. Meanwhile, nanopore confinements can affect order-disorder and order-order transition points in the bulk. The corresponding free, internal, and entropic energies as well as the order parameters are also quantificationally examined to deeply investigate the confined phase mechanisms, and a number of morphological transitions are confirmed to be of first-order. These findings may guide the design of novel nanostructures based on triblock copolymers by introducing confinements.展开更多
Density modulation experiments are powerful experimental schemes for the study of particle transport. The diffusion coefficients （D） and convection velocity （V）, which cannot be evaluated from the particle balance...Density modulation experiments are powerful experimental schemes for the study of particle transport. The diffusion coefficients （D） and convection velocity （V）, which cannot be evaluated from the particle balance in the equilibrium state, can be obtained separately. Further, the estimated values of D and V are determined independent of the absolute value of the particle source rate, which is difficult to obtain experimentally. However, the sensitivities and interpretation of D and V from the modulation experiments need to be considered. This paper describes numerical techniques for solving the particle balance equation of the modulation components. Examples of the analysis are shown regarding the data of LHD experiments, and the results of the modulation experiments are discussed.展开更多
The development of lithium-sulfur batteries(LSBs)is restricted by their poor cycle stability and rate performance due to the low conductivity of sulfur and severe shuttle effect.Herein,an N,O co-doped graphene layered...The development of lithium-sulfur batteries(LSBs)is restricted by their poor cycle stability and rate performance due to the low conductivity of sulfur and severe shuttle effect.Herein,an N,O co-doped graphene layered block(NOGB)with many dents on the graphene sheets is designed as effective sulfur host for high-performance LSB s.The sulfur platelets are physically confined into the dents and closely contacted with the graphene scaffold,ensuring structural stability and high conductivity.The highly doped N and O atoms can prevent the shuttle effect of sulfur species by strong chemical adsorption.Moreover,the micropores on the graphene sheets enable fast Li^+transport through the blocks.As a result,the obtained NOGB/S composite with 76 wt%sulfur content shows a high capacity of 1413 mAh g^-1 at 0.1 C,good rate performance of 433 mAh g^-1 at 10 C,and remarkable stability with 526 mAh g^-1 at after 1000 cycles at 1 C(average decay rate:0.038%per cycle).Our design provides a comprehensive route for simultaneously improving the conductivity,ion transport kinetics,and preventing the shuttle effect in LSBs.展开更多
Ultrathin corrugated metallic structures have been proved to support spoof surface plasmon polariton (SPP) modes on two-dimension (2D) planar microwave circuits.However,to provide stronger field confinement,larger wid...Ultrathin corrugated metallic structures have been proved to support spoof surface plasmon polariton (SPP) modes on two-dimension (2D) planar microwave circuits.However,to provide stronger field confinement,larger width of strip is required to load deeper grooves,which is cumbersome in modern large-scale integrated circuits and chips.In this work,a new spoof SPP transmission line (TL) with zigzag grooves is proposed.This new structure can achieve stronger field confinement compared to conventional one with the same strip width.In other words,the proposed spoof SPP TL behaves equivalently to a conventional one with much larger size.Dispersion analysis theoretically indicates the negative correlation between the ability of field confinement and cutoff frequencies of spoof SPP TLs.Numerical simulations indicate that the cutoff frequency of the proposed TL is lower than the conventional one and can be easily modified with the fixed size.Furthermore,two samples of the new and conventional spoof SPP TLs are fabricated for experimental demonstration.Measured S-parameters and field distributions verify the ultra-strong ability of field confinement of the proposed spoof SPP TL.Hence,this novel spoof SPP structure with ultra-strong field confinement may find wide applications in microwave and terahertz engineering.展开更多
Implant materials,as foreign objects to host,can cause various degrees of inflammation in most cases.The inflammation is triggered by a series of immune responses and directly impacts the tissue regeneration process,w...Implant materials,as foreign objects to host,can cause various degrees of inflammation in most cases.The inflammation is triggered by a series of immune responses and directly impacts the tissue regeneration process,which determines the outcome of tissue repair.The immune responses are complex process involving numerous immune cells and can be divide into innate immune and adaptive immune responses.Once materials are implanted,innate immune responses are activated under the mediation of several immune cells(e.g.neutrophils and macrophages),meanwhile immature dendritic cells(imDCs)are recruited to the implant sites to recognize,internalize and process antigens.Upon antigen uptake,imDCs gradually differentiate into mature dendritic cells(mDCs)and migrate to secondary lymph nodes.In the lymph nodes,mDCs present processed antigen peptides to naive T lymphocytes and activate their antigen specific proliferation,resulting in initiation of adaptive immune responses.Due to their key position in the immune system,serving to bridge innate and adaptive immunity,DCs are crucial to guiding and modulating the immune responses caused by implanted materials.Therefore,figuring out the response of DCs to implanted materials and the exact role of DCs in tissue healing processes will provide deeper insight for the rational design of biomaterials.Previous studies on the effects of implants on immune functions of DCs are mainly focused on physical and chemical properties of the materials(e.g.released chemical composition,surface chemistry,substrate stiffness and surface topography).All these factors will change the microenvironment of the tissue around implant materials,which affect the immune functions of DCs.However,the change of microenvironment not only directly derives from the physical and chemical properties of the material(intrinsic),but also indirectly results from the remodeled extracellular matrix(ECM)caused by implanted materials.When blood or tissue fluid contact with materials after implantation,proteins(e.g.fibrin and collagen)will absorb and deposit on the surface of implants,leading to a provisionally stable matrix with microporous fibrous-liked network structure.It means that the remodeled ECM can provide adhesion sites for recruited DCs and form spatial confinement.DCs,as a kind of cells that are extremely sensitive to mechanical stimuli,theoretically,can response to the mechanical stimuli coming from spatial confinement of remodeled ECM,which may lead to a series of modulations in their cell morphologies and immune functions.Then,the remodeled ECM is a non-negligible mechanical cue.However,to the best of our knowledge,there is a lack of a simple and effective model to establish the relationship between the immune functions of DCs and remodeled ECM.Most studies on the responses of DCs to implanted materials are still based on suspension culture model,which is the normal status of DCs in vitro culture systems.In addition,the processes by which DC exerts immune functions(both endocytosis and antigen presentation)are dynamically physical interaction.It means that the changes of DCs’immune functions are highly correlated with the changes of their biomechanical characteristics caused by remodeled ECM.In this work,we have found that the ECM was remodeled by a large amount of fibrin matrix deposited on the surface of implants in the early stage of the inflammations following implantation.Thus,we used non-toxic salmon fibrin hydrogels with microporous fibrous-liked network structure to mimic the deposited fibrin matrix.Then,human monocyte-derived DCs were cultured on the surface and inside of the fibrin hydrogels to mimic the different spatial confinement states of fibrin matrix.Our results indicated that cell morphologies and cytoskeleton structures of DCs were regulated by the spatial confinement of fibrin hydrogels,resulting in generating mechanical stimuli for DCs.Furthermore,we have found that the biomechanical characteristics and the immune functions of both imDCs and mDC were also modulated.Considering the changes in surface markers,secreted cytokines and biomechanical characteristics of DCs,it indicates that the tendency and magnitude of modulations were highly associated with the spatial confinement of fibrin hydrogels.This model demonstrated that mechanical stimuli deriving from spatial confinement of deposited fibrin matrix is an important factor for regulating the biomechanical characteristics and immune functions of DCs.展开更多
In a charged colloidal system, the influence on depletion interaction between two like-charged macro-ions is studied through Monte Carlo simulation in this paper. The numerical results show that this depletion force i...In a charged colloidal system, the influence on depletion interaction between two like-charged macro-ions is studied through Monte Carlo simulation in this paper. The numerical results show that this depletion force is affected by both the electrostatic interactions between charged spheres and charged plates and by the geometrical factor of the two charged plates, and they further indicate that the influence of geometrical confinement on the depletion interaction is larger than that of electrostatic potential.展开更多
Preferential magnesium(Mg)electrodeposition on separators is a ubiquitous yet poorly understood phenomenon in rechargeable Mg-metal batteries,posing a fundamental challenge to their development.In this work,the synerg...Preferential magnesium(Mg)electrodeposition on separators is a ubiquitous yet poorly understood phenomenon in rechargeable Mg-metal batteries,posing a fundamental challenge to their development.In this work,the synergy effects of interface-accelerating desolvation and spatial confinement have been demonstrated as the essential causation of this counterintuitive experimental phenomenon.At the molecular level,the imide ring(-CO-NR-CO-,in which R represents the phenyl)groups in an artificially introduced polyimide(PI)interlayer facilitate the strong electrostatic affinity towards Mg^(2+),which accelerates the desolvation process for Mg^(2+)solvation structures at the inner Helmholtz plane.At the nucleation scale,the wedge-like concave geometry formed at the PI/current collector interface provides energetically favorable sites for Mg nucleation.This unique architecture reduces the critical nucleus size,thereby significantly lowering nucleation energy barriers.As a result,the satisfactory Coulombic efficiency for Mg plating/stripping(98.22%)and cycle lifespan(1200 cycles,above 100 days)have been achieved,outperforming most of the previous results.This work pioneers a molecular-level understanding of separator-directed Mg deposition and resolves a long-standing confusion in Mg-metal batteries.展开更多
Nucleation,which is the initial step of crystallization,critically governs the polymer crystallization behavior,influencing the crystallization temperature,kinetics,and morphology.However,the direct observation of the...Nucleation,which is the initial step of crystallization,critically governs the polymer crystallization behavior,influencing the crystallization temperature,kinetics,and morphology.However,the direct observation of the nucleation process in polymers remains elusive owing to spatial and temporal resolution limitations.This feature article summarizes the recent progress in understanding polymer nucleation within confined and interface-dominated environments,focusing on three representative systems:anodic aluminum oxide templates and nanocomposites containing nanoparticles or nanosheets.The interplay between finite size and interfacial effects has revealed some novel phenomena,such as homogeneous nucleation,surface nucleation,prefreezing,and supernucleation.展开更多
MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper...MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper doping and carbon-based confinement.Residual carbon(RC),derived from acid-washed coal gasification fine slag(CGFS),serves as a conductive and porous framework for the directional growth of Cu-doped MnO_(2) nanowires(CMO@RC).The synergistic modulation of Cu-induced electronic structure tuning and carbon confinement induced mechanical/electrical stabilization significantly enhances Zn^(2+) transport and electrochemical performance.CMO@RC achieves a high capacity of 563 mA·h·g^(−1) at 0.1 A·g^(−1) and maintains 106%after 1000 cycles at 1 A·g^(−1).Kinetic analyses confirm the dual-path Zn^(2+) diffusion and accelerated reaction kinetics,while DFT calculations reveal that Cu doping enhances Mn 3d orbital hybridization and electron interaction with carbon,elevating the density of states near the Fermi level and reducing charge transfer barriers.Furthermore,pouch cell testing demonstrates outstanding flexibility and mechanical resilience.This study provides a cost-effective and scalable strategy for high-performance AZIBs,leveraging both experimental and theoretical validations.展开更多
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
Strategically coupling nanoparticle hybrids and internal thermosensitive molecular switches establishes an innovative paradigm for constructing micro/nanoscale-reconfigurable robots,facilitating energyefficient CO_(2)...Strategically coupling nanoparticle hybrids and internal thermosensitive molecular switches establishes an innovative paradigm for constructing micro/nanoscale-reconfigurable robots,facilitating energyefficient CO_(2) management in life-support systems of confined space.Here,a micro/nano-reconfigurable robot is constructed from the CO_(2) molecular hunters,temperature-sensitive molecular switch,solar photothermal conversion,and magnetically-driven function engines.The molecular hunters within the molecular extension state can capture 6.19 mmol g^(−1) of CO_(2) to form carbamic acid and ammonium bicarbonate.Interestingly,the molecular switch of the robot activates a molecular curling state that facilitates CO_(2) release through nano-reconfiguration,which is mediated by the temperature-sensitive curling of Pluronic F127 molecular chains during the photothermal desorption.Nano-reconfiguration of robot alters the amino microenvironment,including increasing surface electrostatic potential of the amino group and decreasing overall lowest unoccupied molecular orbital energy level.This weakened the nucleophilic attack ability of the amino group toward the adsorption product derivatives,thereby inhibiting the side reactions that generate hard-to-decompose urea structures,achieving the lowest regeneration temperature of 55℃ reported to date.The engine of the robot possesses non-contact magnetically-driven micro-reconfiguration capability to achieve efficient photothermal regeneration while avoiding local overheating.Notably,the robot successfully prolonged the survival time of mice in the sealed container by up to 54.61%,effectively addressing the issue of carbon suffocation in confined spaces.This work significantly enhances life-support systems for deep-space exploration,while stimulating innovations in sustainable carbon management technologies for terrestrial extreme environments.展开更多
When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may aff...When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may affect the initiation and propagation of fractures within brittle materials.Understanding the physical mechanisms leading to failure is crucial for underground engineering applications and geo-energy exploration and storage.We conducted triaxial compression experiments on porous Bentheim sandstone samples at different stress paths and pressure change rates.First,at a constant confining pressure of 35 MPa and pore pressure of 5 MPa,intact cylindrical samples were axially loaded up to about 85%of the peak strength.Subsequently,the axial piston position was fixed,and then either the pore pressure was increased or the confining pressure was decreased at two different rates(0.5 MPa/min or 2 MPa/min),leading to final catastrophic failure.The mechanical results revealed that samples subjected to higher rates of decreasing effective confining pressure exhibited larger stress drop rates,higher slip rates,higher total breakdown work,higher rates of acoustic emissions(AEs)before failure,and higher post-failure AE decay rates.In contrast,the applied stress path did not significantly affect rock failure characteristics.Comparison of located AE events with post-mortem microstructures of deformed samples shows a good agreement.The AE source type determined from the P-wave first-motion polarity shows that shear failure dominated the fracture process when approaching failure.Gutenberg-Richter b-values revealed a significant decrease before failure in all tests.Our results indicate that,in contrast to the stress path,the rate of effective stress change strongly affects fracturing behavior and AE rate changes.展开更多
Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined sp...Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined spaces,and millimeter-scale height restrictions,presenting significant challenges to conventional inspection methods.Here,we present an ultrasonic microrobot(weight,80 mg;dimensions,24 mm×7 mm;thickness,210μm)to realize agile and bidirectional navigation in narrow pipelines.The ultrathin structural design of the robot is achieved through a high-performance piezoelectric composite film microstructure based on MEMS technology.The robot exhibits various vibration modes when driven by ultrasonic frequency signals,its motion speed reaches81 cm s-1 at 54.8 k Hz,exceeding that of the fastest piezoelectric microrobots,and its forward and backward motion direction is controllable through frequency modulation,while the minimum driving voltage for initial movement can be as low as 3 VP-P.Additionally,the robot can effortlessly climb slopes up to 24.25°and carry loads more than 36 times its weight.The robot is capable of agile navigation through curved L-shaped pipes,pipes made of various materials(acrylic,stainless steel,and polyvinyl chloride),and even over water.To further demonstrate its inspection capabilities,a micro-endoscope camera is integrated into the robot,enabling real-time image capture inside glass pipes.展开更多
High ground temperature and unloading disturbance have emerged as critical factors impacting the property of cemented gauge-fly ash backfill(CGFB).The characteristics of energy and damage in CGFB were analyzed under c...High ground temperature and unloading disturbance have emerged as critical factors impacting the property of cemented gauge-fly ash backfill(CGFB).The characteristics of energy and damage in CGFB were analyzed under conditions of high ground temperature and unloading by conducting triaxial unloading tests with different initial confining pressures on CGFB that had been cured at various temperatures.Based on dissipative energy,triaxial unloading confining pressure damage constitutive model of CGFB was constructed.It has been demonstrated that the ratio of elastic strain energy in CGFB decreases and the ratio of dissipated energy increases at the end of unloading increases under higher curing temperature.The change in the elastic energy consumption ratio curve of CGFB,which shifts from a gradual increase to a swift rise at a certain"inflection point",can be utilized as a criterion for evaluating the failure of the unloading strength of CGFB.The triaxial unloading damage constitutive model for CGFB divides the damage progression into three distinct phases:initial damage stage,accelerated damage development stage,and rapid damage growth stage.The research findings offer a theoretical foundation for evaluating the extent of damage to CGFB caused by the combined influences of elevated ground temperature and unloading.展开更多
Groundwater level(GWL)is a key indicator used to accurately assess groundwater resources and form the foundation for ef-fective groundwater management.This paper integrates a Gate Recurrent Unit(GRU)model with a Multi...Groundwater level(GWL)is a key indicator used to accurately assess groundwater resources and form the foundation for ef-fective groundwater management.This paper integrates a Gate Recurrent Unit(GRU)model with a Multi-head Self-attention mechan-ism(MSAM-GRU)to simulate GWLs in both confined and unconfined aquifers simultaneously.The model innovatively captures the lag times between GWLs in the unconfined aquifer and precipitation,as well as between GWLs in the confined aquifer and the upper aquifer.We have assessed the effectiveness of the proposed model using a case study in the Beijing Plain,China from January 2005 to December 2020.With the consideration of lag times,the results indicated that the MSAM-GRU model exhibits a maximum 67%and 73%reduction in RMSE compared to the Attention mechanism-GRU(AM-GRU)and GRU model,respectively.MSAM-GRU model exhibited a 31%reduction in RMSE and a 0.12 increase in R^(2) compared to the same model that do not account for lag time.In Region I,the shortest lag time of GWL in the unconfined aquifer was two months,while that in the confined aquifer was three months,indicating a longer delayed response in the confined aquifer.MSAM-GRU model considering lag time,was then applied to simulate the GWLs in the unconfined aquifer under different scenarios and to analyze whether GWL fluctuations affect subway operations.The simulation res-ults showed that under the scenario 1,the GWL in the unconfined aquifer would rise above the depth of subway station floor,threaten-ing the operation of subways.This study can provide reliable technical support for the accurate simulation of GWLs in multi-aquifer systems.展开更多
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
In this work,a surface-potential based compact model focusing on the quantum confinement effects of ultimately scaled gate-all-around(GAA)MOSFET is presented.Energy quantization with sub-band formation along the radiu...In this work,a surface-potential based compact model focusing on the quantum confinement effects of ultimately scaled gate-all-around(GAA)MOSFET is presented.Energy quantization with sub-band formation along the radius direction of cylindrical GAAs or thickness direction of nanosheet GAAs leads to significant quantization effects.An analytical model of surface potentials is developed by solving the Poisson equation with incorporating sub-band effects.In combination with the existing transport model framework,charge-voltage and current-voltage formulations are developed based on the surface potential.The model formulations are then extensively validated using TCAD numerical simulations as well as Si data of nanosheet GAA MOSFETs.Simulations of typical circuits verify the model robustness and convergence for its applications in GAA technology.展开更多
We have proposed and demonstrated hybrid Al Ga In As/Si Fabry–Pérot(FP) lasers, with the FP cavity facet covered by the p-electrode metal for enhancing mode confinement. Continuous-wave lasing is obtained at roo...We have proposed and demonstrated hybrid Al Ga In As/Si Fabry–Pérot(FP) lasers, with the FP cavity facet covered by the p-electrode metal for enhancing mode confinement. Continuous-wave lasing is obtained at room temperature with a threshold current of 45 m A for the hybrid FP laser with a cavity length of 415 μm and a width of 7 μm. Near-field optical microscope images indicate an efficient output emission from the underneath evanescently-coupled silicon waveguide. Furthermore, single-mode lasing with a side-mode suppression-ratio of29 d B and a threshold current of 16 m A is realized for the 150 μm-long hybrid FP laser.展开更多
基金supported by National Natural Science Foundation of China(Nos.52474052 and 52074248)Young Elite Scientists Sponsorship Program by Beijing Association for Science and Technology,China(No.BYESS2023414)Scientific Research Innovation Capability Support Project for Young Faculty,China(No.ZYGXQNJSKYCXNLZCXM-E14).
文摘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.
基金Projects(51774326,41807259)supported by the National Natural Science Foundation of ChinaProject(MDPC201917)supported by Mining Disaster Prevention and Control Ministry Key Laboratory at Shandong University of Science and Technology,China。
文摘In this research,a series of biaxial compression and biaxial fatigue tests were conducted to investigate the mechanical behaviors of marble and sandstone under biaxial confinements.Experimental results demonstrate that the biaxial compressive strength of rocks under biaxial compression increases firstly,and subsequently decreases with increase of the intermediate principal stress.The fatigue failure characteristics of the rocks in biaxial fatigue tests are functions of the peak value of fatigue loads,the intermediate principal stress and the rock lithology.With the increase of the peak values of fatigue loads,the fatigue lives of rocks decrease.The intermediate principal stress strengthens the resistance ability of rocks to fatigue loads except considering the strength increasing under biaxial confinements.The fatigue lives of rocks increase with the increase of the intermediate principal stress under the same ratio of the fatigue load and their biaxial compressive strength.The acoustic emission(AE)and fragments studies showed that the sandstone has higher ability to resist the fatigue loads compared to the marble,and the marble generated a greater number of smaller fragments after fatigue failure compared to the sandstone.So,it can be inferred that the rock breaking efficiency and rock burst is higher or severer induced by fatigue loading than that induced by monotonous quasi-static loading,especially for hard rocks.
基金supported by the General Program of National Natural Science Foundation of China(Nos. 21174131, 20974081, 21074096, and 21104060)the Natural Science Foundation of Zhejiang Province(Nos. Y4090174 and Y6100033)
文摘The self-assembly of linear ABC triblock copolymers under cylindrical confinements is investigated in two- dimensional space using the real-space self-consistent field theory. The effects of confinement degrees and preferential strengths on the triblock copolymer phase behaviors with special polymer parameters are first considered. On one hand, different confinement degrees cause different phase behaviors in nanopores with the neutral surfaces. Moreover, the strongly preferential surface fields can surpass the confinement degrees and volume fractions in determing the confined phase behaviors. On the other hand, in contrast, confined morphologies are more sensitive to the variations in the A-preferential surface field strength. Subsequently, the incompatibility degrees between different blocks are systematically varied under cylindrical nanopore confinements. Under cylindrical nanopore confinements, the morphologies are very sensitive to the variations in the incompatibility degrees. Meanwhile, nanopore confinements can affect order-disorder and order-order transition points in the bulk. The corresponding free, internal, and entropic energies as well as the order parameters are also quantificationally examined to deeply investigate the confined phase mechanisms, and a number of morphological transitions are confirmed to be of first-order. These findings may guide the design of novel nanostructures based on triblock copolymers by introducing confinements.
基金supported in part by the JSPS-CAS Core-University Program in the field of Plasma and Nuclear Fusion
文摘Density modulation experiments are powerful experimental schemes for the study of particle transport. The diffusion coefficients （D） and convection velocity （V）, which cannot be evaluated from the particle balance in the equilibrium state, can be obtained separately. Further, the estimated values of D and V are determined independent of the absolute value of the particle source rate, which is difficult to obtain experimentally. However, the sensitivities and interpretation of D and V from the modulation experiments need to be considered. This paper describes numerical techniques for solving the particle balance equation of the modulation components. Examples of the analysis are shown regarding the data of LHD experiments, and the results of the modulation experiments are discussed.
基金supported by the National Natural Science Foundation of China(Nos.51672055,51972342,51872656,and 51702275)the Taishan Scholar Project of Shandong Province(ts20190922)+3 种基金the Key Basic Research Project of Natural Science Foundation of Shandong Province(ZR2019ZD51)the Xinjiang Tianshan Xuesong Project(2018XS28)the Scientific Research Program of the Higher Education Institution of Xinjiang(XJEDU2017S003)the Xinjiang Tianchi Doctoral Project。
文摘The development of lithium-sulfur batteries(LSBs)is restricted by their poor cycle stability and rate performance due to the low conductivity of sulfur and severe shuttle effect.Herein,an N,O co-doped graphene layered block(NOGB)with many dents on the graphene sheets is designed as effective sulfur host for high-performance LSB s.The sulfur platelets are physically confined into the dents and closely contacted with the graphene scaffold,ensuring structural stability and high conductivity.The highly doped N and O atoms can prevent the shuttle effect of sulfur species by strong chemical adsorption.Moreover,the micropores on the graphene sheets enable fast Li^+transport through the blocks.As a result,the obtained NOGB/S composite with 76 wt%sulfur content shows a high capacity of 1413 mAh g^-1 at 0.1 C,good rate performance of 433 mAh g^-1 at 10 C,and remarkable stability with 526 mAh g^-1 at after 1000 cycles at 1 C(average decay rate:0.038%per cycle).Our design provides a comprehensive route for simultaneously improving the conductivity,ion transport kinetics,and preventing the shuttle effect in LSBs.
基金the National Natural Science Foundation of China under Grant Nos.61871127,61701246,61631007,61571117,61501112,61501117,61522106,61722106,61701107,and 61701108,and 111 Project under Grant No.111-2-05.
文摘Ultrathin corrugated metallic structures have been proved to support spoof surface plasmon polariton (SPP) modes on two-dimension (2D) planar microwave circuits.However,to provide stronger field confinement,larger width of strip is required to load deeper grooves,which is cumbersome in modern large-scale integrated circuits and chips.In this work,a new spoof SPP transmission line (TL) with zigzag grooves is proposed.This new structure can achieve stronger field confinement compared to conventional one with the same strip width.In other words,the proposed spoof SPP TL behaves equivalently to a conventional one with much larger size.Dispersion analysis theoretically indicates the negative correlation between the ability of field confinement and cutoff frequencies of spoof SPP TLs.Numerical simulations indicate that the cutoff frequency of the proposed TL is lower than the conventional one and can be easily modified with the fixed size.Furthermore,two samples of the new and conventional spoof SPP TLs are fabricated for experimental demonstration.Measured S-parameters and field distributions verify the ultra-strong ability of field confinement of the proposed spoof SPP TL.Hence,this novel spoof SPP structure with ultra-strong field confinement may find wide applications in microwave and terahertz engineering.
基金funded by grants from the National Natural Science Foundation of China ( 31771014, 11762006,31660258,31860262,11762006,81460254 )the 2011 Collaborative Innovation Program of Guizhou Province ( 2015-04)+1 种基金the Science and Technology Innovative Talent Team of Guizhou Province ( 2015-4021)the Science and Technology Foundation of Guizhou Province ( 2018-1412,2016-5676,2017-5718)
文摘Implant materials,as foreign objects to host,can cause various degrees of inflammation in most cases.The inflammation is triggered by a series of immune responses and directly impacts the tissue regeneration process,which determines the outcome of tissue repair.The immune responses are complex process involving numerous immune cells and can be divide into innate immune and adaptive immune responses.Once materials are implanted,innate immune responses are activated under the mediation of several immune cells(e.g.neutrophils and macrophages),meanwhile immature dendritic cells(imDCs)are recruited to the implant sites to recognize,internalize and process antigens.Upon antigen uptake,imDCs gradually differentiate into mature dendritic cells(mDCs)and migrate to secondary lymph nodes.In the lymph nodes,mDCs present processed antigen peptides to naive T lymphocytes and activate their antigen specific proliferation,resulting in initiation of adaptive immune responses.Due to their key position in the immune system,serving to bridge innate and adaptive immunity,DCs are crucial to guiding and modulating the immune responses caused by implanted materials.Therefore,figuring out the response of DCs to implanted materials and the exact role of DCs in tissue healing processes will provide deeper insight for the rational design of biomaterials.Previous studies on the effects of implants on immune functions of DCs are mainly focused on physical and chemical properties of the materials(e.g.released chemical composition,surface chemistry,substrate stiffness and surface topography).All these factors will change the microenvironment of the tissue around implant materials,which affect the immune functions of DCs.However,the change of microenvironment not only directly derives from the physical and chemical properties of the material(intrinsic),but also indirectly results from the remodeled extracellular matrix(ECM)caused by implanted materials.When blood or tissue fluid contact with materials after implantation,proteins(e.g.fibrin and collagen)will absorb and deposit on the surface of implants,leading to a provisionally stable matrix with microporous fibrous-liked network structure.It means that the remodeled ECM can provide adhesion sites for recruited DCs and form spatial confinement.DCs,as a kind of cells that are extremely sensitive to mechanical stimuli,theoretically,can response to the mechanical stimuli coming from spatial confinement of remodeled ECM,which may lead to a series of modulations in their cell morphologies and immune functions.Then,the remodeled ECM is a non-negligible mechanical cue.However,to the best of our knowledge,there is a lack of a simple and effective model to establish the relationship between the immune functions of DCs and remodeled ECM.Most studies on the responses of DCs to implanted materials are still based on suspension culture model,which is the normal status of DCs in vitro culture systems.In addition,the processes by which DC exerts immune functions(both endocytosis and antigen presentation)are dynamically physical interaction.It means that the changes of DCs’immune functions are highly correlated with the changes of their biomechanical characteristics caused by remodeled ECM.In this work,we have found that the ECM was remodeled by a large amount of fibrin matrix deposited on the surface of implants in the early stage of the inflammations following implantation.Thus,we used non-toxic salmon fibrin hydrogels with microporous fibrous-liked network structure to mimic the deposited fibrin matrix.Then,human monocyte-derived DCs were cultured on the surface and inside of the fibrin hydrogels to mimic the different spatial confinement states of fibrin matrix.Our results indicated that cell morphologies and cytoskeleton structures of DCs were regulated by the spatial confinement of fibrin hydrogels,resulting in generating mechanical stimuli for DCs.Furthermore,we have found that the biomechanical characteristics and the immune functions of both imDCs and mDC were also modulated.Considering the changes in surface markers,secreted cytokines and biomechanical characteristics of DCs,it indicates that the tendency and magnitude of modulations were highly associated with the spatial confinement of fibrin hydrogels.This model demonstrated that mechanical stimuli deriving from spatial confinement of deposited fibrin matrix is an important factor for regulating the biomechanical characteristics and immune functions of DCs.
基金supported by the National Natural Science Foundation of China (Grant Nos 10375042 and 10775018)the Scientific Research Fund of Hunan Provincial Education Department and Hunan Provincial Natural Science Foundation of China (GrantNo 08jj6043)the Construct Program of the Key discipline in Hunan Province,China
文摘In a charged colloidal system, the influence on depletion interaction between two like-charged macro-ions is studied through Monte Carlo simulation in this paper. The numerical results show that this depletion force is affected by both the electrostatic interactions between charged spheres and charged plates and by the geometrical factor of the two charged plates, and they further indicate that the influence of geometrical confinement on the depletion interaction is larger than that of electrostatic potential.
基金supported by the National Natural Science Foundation of China(22279068,52374306)the Taishan Scholars of Shandong Province(tsqn202408202)the Qingdao New Energy Shandong Laboratory Open Project(QNESL OP202312)。
文摘Preferential magnesium(Mg)electrodeposition on separators is a ubiquitous yet poorly understood phenomenon in rechargeable Mg-metal batteries,posing a fundamental challenge to their development.In this work,the synergy effects of interface-accelerating desolvation and spatial confinement have been demonstrated as the essential causation of this counterintuitive experimental phenomenon.At the molecular level,the imide ring(-CO-NR-CO-,in which R represents the phenyl)groups in an artificially introduced polyimide(PI)interlayer facilitate the strong electrostatic affinity towards Mg^(2+),which accelerates the desolvation process for Mg^(2+)solvation structures at the inner Helmholtz plane.At the nucleation scale,the wedge-like concave geometry formed at the PI/current collector interface provides energetically favorable sites for Mg nucleation.This unique architecture reduces the critical nucleus size,thereby significantly lowering nucleation energy barriers.As a result,the satisfactory Coulombic efficiency for Mg plating/stripping(98.22%)and cycle lifespan(1200 cycles,above 100 days)have been achieved,outperforming most of the previous results.This work pioneers a molecular-level understanding of separator-directed Mg deposition and resolves a long-standing confusion in Mg-metal batteries.
基金financially supported by the National Natural Science Foundation of China(Nos.21873109 and 21922308)。
文摘Nucleation,which is the initial step of crystallization,critically governs the polymer crystallization behavior,influencing the crystallization temperature,kinetics,and morphology.However,the direct observation of the nucleation process in polymers remains elusive owing to spatial and temporal resolution limitations.This feature article summarizes the recent progress in understanding polymer nucleation within confined and interface-dominated environments,focusing on three representative systems:anodic aluminum oxide templates and nanocomposites containing nanoparticles or nanosheets.The interplay between finite size and interfacial effects has revealed some novel phenomena,such as homogeneous nucleation,surface nucleation,prefreezing,and supernucleation.
基金support from the Key projects of scientific research projects of universities in Anhui Province(2024AH050360).
文摘MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper doping and carbon-based confinement.Residual carbon(RC),derived from acid-washed coal gasification fine slag(CGFS),serves as a conductive and porous framework for the directional growth of Cu-doped MnO_(2) nanowires(CMO@RC).The synergistic modulation of Cu-induced electronic structure tuning and carbon confinement induced mechanical/electrical stabilization significantly enhances Zn^(2+) transport and electrochemical performance.CMO@RC achieves a high capacity of 563 mA·h·g^(−1) at 0.1 A·g^(−1) and maintains 106%after 1000 cycles at 1 A·g^(−1).Kinetic analyses confirm the dual-path Zn^(2+) diffusion and accelerated reaction kinetics,while DFT calculations reveal that Cu doping enhances Mn 3d orbital hybridization and electron interaction with carbon,elevating the density of states near the Fermi level and reducing charge transfer barriers.Furthermore,pouch cell testing demonstrates outstanding flexibility and mechanical resilience.This study provides a cost-effective and scalable strategy for high-performance AZIBs,leveraging both experimental and theoretical validations.
基金supported by the National Natural Science Foundation of China(22269020,U23A20582,42167068)the Gansu Province Higher Education Industry Support Plan Project(2023CYZC-17)+1 种基金2024 Major Cultivation Project for University Research and Innovation Platforms(2024CXPT-10)the Key Project of the Natural Science Foundation of Gansu Province(25JRRA004).
文摘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.
基金supported by the National Natural Science Foundation of China(22168008,22378085)the Guangxi Natural Science Foundation(2024GXNSFDA010053)+1 种基金the Technology Development Project of Guangxi Bossco Environmental Protection Technology Co.,Ltd(202100039)Innovation Project of Guangxi Graduate Education(YCBZ2024065).
文摘Strategically coupling nanoparticle hybrids and internal thermosensitive molecular switches establishes an innovative paradigm for constructing micro/nanoscale-reconfigurable robots,facilitating energyefficient CO_(2) management in life-support systems of confined space.Here,a micro/nano-reconfigurable robot is constructed from the CO_(2) molecular hunters,temperature-sensitive molecular switch,solar photothermal conversion,and magnetically-driven function engines.The molecular hunters within the molecular extension state can capture 6.19 mmol g^(−1) of CO_(2) to form carbamic acid and ammonium bicarbonate.Interestingly,the molecular switch of the robot activates a molecular curling state that facilitates CO_(2) release through nano-reconfiguration,which is mediated by the temperature-sensitive curling of Pluronic F127 molecular chains during the photothermal desorption.Nano-reconfiguration of robot alters the amino microenvironment,including increasing surface electrostatic potential of the amino group and decreasing overall lowest unoccupied molecular orbital energy level.This weakened the nucleophilic attack ability of the amino group toward the adsorption product derivatives,thereby inhibiting the side reactions that generate hard-to-decompose urea structures,achieving the lowest regeneration temperature of 55℃ reported to date.The engine of the robot possesses non-contact magnetically-driven micro-reconfiguration capability to achieve efficient photothermal regeneration while avoiding local overheating.Notably,the robot successfully prolonged the survival time of mice in the sealed container by up to 54.61%,effectively addressing the issue of carbon suffocation in confined spaces.This work significantly enhances life-support systems for deep-space exploration,while stimulating innovations in sustainable carbon management technologies for terrestrial extreme environments.
文摘When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may affect the initiation and propagation of fractures within brittle materials.Understanding the physical mechanisms leading to failure is crucial for underground engineering applications and geo-energy exploration and storage.We conducted triaxial compression experiments on porous Bentheim sandstone samples at different stress paths and pressure change rates.First,at a constant confining pressure of 35 MPa and pore pressure of 5 MPa,intact cylindrical samples were axially loaded up to about 85%of the peak strength.Subsequently,the axial piston position was fixed,and then either the pore pressure was increased or the confining pressure was decreased at two different rates(0.5 MPa/min or 2 MPa/min),leading to final catastrophic failure.The mechanical results revealed that samples subjected to higher rates of decreasing effective confining pressure exhibited larger stress drop rates,higher slip rates,higher total breakdown work,higher rates of acoustic emissions(AEs)before failure,and higher post-failure AE decay rates.In contrast,the applied stress path did not significantly affect rock failure characteristics.Comparison of located AE events with post-mortem microstructures of deformed samples shows a good agreement.The AE source type determined from the P-wave first-motion polarity shows that shear failure dominated the fracture process when approaching failure.Gutenberg-Richter b-values revealed a significant decrease before failure in all tests.Our results indicate that,in contrast to the stress path,the rate of effective stress change strongly affects fracturing behavior and AE rate changes.
基金supported by the National Key Research and Development Program of China(No.2024YFB3212901)National Natural Science Foundation of China(12072189)the Medicine and Engineering Interdisciplinary Research Fund of Shanghai Jiao Tong University(No.YG2025ZD05)。
文摘Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined spaces,and millimeter-scale height restrictions,presenting significant challenges to conventional inspection methods.Here,we present an ultrasonic microrobot(weight,80 mg;dimensions,24 mm×7 mm;thickness,210μm)to realize agile and bidirectional navigation in narrow pipelines.The ultrathin structural design of the robot is achieved through a high-performance piezoelectric composite film microstructure based on MEMS technology.The robot exhibits various vibration modes when driven by ultrasonic frequency signals,its motion speed reaches81 cm s-1 at 54.8 k Hz,exceeding that of the fastest piezoelectric microrobots,and its forward and backward motion direction is controllable through frequency modulation,while the minimum driving voltage for initial movement can be as low as 3 VP-P.Additionally,the robot can effortlessly climb slopes up to 24.25°and carry loads more than 36 times its weight.The robot is capable of agile navigation through curved L-shaped pipes,pipes made of various materials(acrylic,stainless steel,and polyvinyl chloride),and even over water.To further demonstrate its inspection capabilities,a micro-endoscope camera is integrated into the robot,enabling real-time image capture inside glass pipes.
基金Project(2024YFC2911000)supported by the National Key Research and Development Program Young Scientist Project,ChinaProject(2022HWYQ-078)supported by the Natural Science Foundation of Shandong Province of China+1 种基金Project(tsqn202103074)supported by the"Taishan Scholars Young Expert Program"of Shandong Province,ChinaProject(2023GX051)supported by the Tai'an Science and Technology Innovation Development Project(Policy Guidance),China。
文摘High ground temperature and unloading disturbance have emerged as critical factors impacting the property of cemented gauge-fly ash backfill(CGFB).The characteristics of energy and damage in CGFB were analyzed under conditions of high ground temperature and unloading by conducting triaxial unloading tests with different initial confining pressures on CGFB that had been cured at various temperatures.Based on dissipative energy,triaxial unloading confining pressure damage constitutive model of CGFB was constructed.It has been demonstrated that the ratio of elastic strain energy in CGFB decreases and the ratio of dissipated energy increases at the end of unloading increases under higher curing temperature.The change in the elastic energy consumption ratio curve of CGFB,which shifts from a gradual increase to a swift rise at a certain"inflection point",can be utilized as a criterion for evaluating the failure of the unloading strength of CGFB.The triaxial unloading damage constitutive model for CGFB divides the damage progression into three distinct phases:initial damage stage,accelerated damage development stage,and rapid damage growth stage.The research findings offer a theoretical foundation for evaluating the extent of damage to CGFB caused by the combined influences of elevated ground temperature and unloading.
基金Under the auspices of the National Key Research and Development Program of China(No.2024YFC3713102)。
文摘Groundwater level(GWL)is a key indicator used to accurately assess groundwater resources and form the foundation for ef-fective groundwater management.This paper integrates a Gate Recurrent Unit(GRU)model with a Multi-head Self-attention mechan-ism(MSAM-GRU)to simulate GWLs in both confined and unconfined aquifers simultaneously.The model innovatively captures the lag times between GWLs in the unconfined aquifer and precipitation,as well as between GWLs in the confined aquifer and the upper aquifer.We have assessed the effectiveness of the proposed model using a case study in the Beijing Plain,China from January 2005 to December 2020.With the consideration of lag times,the results indicated that the MSAM-GRU model exhibits a maximum 67%and 73%reduction in RMSE compared to the Attention mechanism-GRU(AM-GRU)and GRU model,respectively.MSAM-GRU model exhibited a 31%reduction in RMSE and a 0.12 increase in R^(2) compared to the same model that do not account for lag time.In Region I,the shortest lag time of GWL in the unconfined aquifer was two months,while that in the confined aquifer was three months,indicating a longer delayed response in the confined aquifer.MSAM-GRU model considering lag time,was then applied to simulate the GWLs in the unconfined aquifer under different scenarios and to analyze whether GWL fluctuations affect subway operations.The simulation res-ults showed that under the scenario 1,the GWL in the unconfined aquifer would rise above the depth of subway station floor,threaten-ing the operation of subways.This study can provide reliable technical support for the accurate simulation of GWLs in multi-aquifer systems.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.12074399,12204500,and 12004403)the Key Projects of Intergovernmental International Scientific and Technological Innovation Cooperation(No.2021YFE0116700)+1 种基金the Shanghai Natural Science Foundation(No.20ZR1464400)the Shanghai Sailing Program(No.22YF1455300).
文摘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.
基金supported in part by the Natural Science Foundation of China(62125401 and 62074006)the major scientific instruments and equipments development grant(61927901)the Shenzhen Fundamental Research Program(GXWD20200827114656001).
文摘In this work,a surface-potential based compact model focusing on the quantum confinement effects of ultimately scaled gate-all-around(GAA)MOSFET is presented.Energy quantization with sub-band formation along the radius direction of cylindrical GAAs or thickness direction of nanosheet GAAs leads to significant quantization effects.An analytical model of surface potentials is developed by solving the Poisson equation with incorporating sub-band effects.In combination with the existing transport model framework,charge-voltage and current-voltage formulations are developed based on the surface potential.The model formulations are then extensively validated using TCAD numerical simulations as well as Si data of nanosheet GAA MOSFETs.Simulations of typical circuits verify the model robustness and convergence for its applications in GAA technology.
基金supported by the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(No.QYZDJ-SSW-JSC002)the NSFC/RGC Joint Project(No.61431166003)the National Natural Science Foundation of China(No.61377105)
文摘We have proposed and demonstrated hybrid Al Ga In As/Si Fabry–Pérot(FP) lasers, with the FP cavity facet covered by the p-electrode metal for enhancing mode confinement. Continuous-wave lasing is obtained at room temperature with a threshold current of 45 m A for the hybrid FP laser with a cavity length of 415 μm and a width of 7 μm. Near-field optical microscope images indicate an efficient output emission from the underneath evanescently-coupled silicon waveguide. Furthermore, single-mode lasing with a side-mode suppression-ratio of29 d B and a threshold current of 16 m A is realized for the 150 μm-long hybrid FP laser.
