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Finite-size effects in a D-dimensional ideal Fermi gas 被引量:3
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作者 苏国珍 欧聪杰 +1 位作者 Wang A Qiu-Ping 陈金灿 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第12期5189-5195,共7页
By using the Euler-MacLaurin formula, this paper studies the thermodynamic properties of an ideal Fermi gas confined in a D-dimensional rectangular container. The general expressions of the thermodynamic quantities wi... By using the Euler-MacLaurin formula, this paper studies the thermodynamic properties of an ideal Fermi gas confined in a D-dimensional rectangular container. The general expressions of the thermodynamic quantities with the finite-size corrections are given explicitly and the effects of the size and shape of the container on the properties of the system are discussed. It is shown that the corrections of the thermodynamic quantities due to the finite-size effects are significant to be considered for the case of strong degeneracy but negligible for the case of weak degeneracy or non-degeneracy. It is important to find that some familiar conclusions under the thermodynamic limit are no longer valid for the finite-size systems and there are some novel characteristics resulting from the finite-size effects, such as the nonextensivity of the system, the anisotropy of the pressure, and so on. 展开更多
关键词 finite-size effect ideal Fermi gas thermodynamic property
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Influences of finite-size effects on the self-organized critical-ity of forest-fire model 被引量:9
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作者 Weiguo Song Weicheng Fan Binghong Wang 《Chinese Science Bulletin》 SCIE EI CAS 2002年第3期177-180,共4页
The influences of finite-size effects on the self-organized criticality (SOC) of the traditional forest-fire model are investigated by means of a new method. The forest size is originally set to a value much greater t... The influences of finite-size effects on the self-organized criticality (SOC) of the traditional forest-fire model are investigated by means of a new method. The forest size is originally set to a value much greater than the correla-tion length of the forest. Finite-size effects are then studied by equally dividing the forest into more and more separate subsystems on condition that the forest size, igniting prob-ability and planting probability are invariant. A new phe-nomenon, i.e. the finite-size effects with one-side frequency peak, is observed. The boundary between two neighboring subsystems can be regarded as a firebreak. The concept of ’separation ability’ is introduced to represent the probability for the firebreak to block off the fire successfully. Restrain-ing effects of separation ability on finite-size effects are ana-lyzed. Finite-size effects and separation ability, as well as their relations are found to have practical importance to the actual forest-fire protection. 展开更多
关键词 forest-fire model SELF-ORGANIZED CRITICALITY cellular AUTOMATA finite-size effects.
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Gas-liquid phase coexistence and finite-size effects in a two-dimensional Lennard-Jones system 被引量:1
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作者 OUYANG WenZe XU ShengHua SUN ZhiWei 《Chinese Science Bulletin》 SCIE EI CAS 2011年第26期2773-2779,共7页
The gas-liquid phase coexistence in a two-dimensional Lennard-Jones system is investigated using Maxwell construction method together with molecular dynamics simulations.The results of phase coexistence in different t... The gas-liquid phase coexistence in a two-dimensional Lennard-Jones system is investigated using Maxwell construction method together with molecular dynamics simulations.The results of phase coexistence in different truncations of the potential are compared with data obtained from the literature,and the corresponding critical properties calculated.The crossover from Ising-like to mean field behavior is observed and confirmed as the temperature approaches the critical point from below.Performing simulations on systems with different sizes,we find that a finite size effect is more significant than those shown in most of the previous results,and a lower critical temperature is obtained when the full extent of this finite size effect is considered. 展开更多
关键词 Lennard-Jones system two dimension gas-liquid phase coexistence finite size effect molecular dynamics
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Effects of finite-size neutrally buoyant particles on the turbulent channel flow at a Reynolds number of 395
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作者 Zhaosheng YU Chenlin ZHU +1 位作者 Yu WANG Xueming SHAO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第2期293-304,共12页
A direct-forcing fictitious domain(DFFD) method is used to perform fully resolved numerical simulations of turbulent channel flows laden with large neutrally buoyant particles. The effects of the particles on the turb... A direct-forcing fictitious domain(DFFD) method is used to perform fully resolved numerical simulations of turbulent channel flows laden with large neutrally buoyant particles. The effects of the particles on the turbulence(including the mean velocity,the root mean square(RMS) of the velocity fluctuation, the probability density function(PDF) of the velocity, and the vortex structures) at a friction Reynolds number of 395 are investigated. The results show that the drag-reduction effect caused by finite-size spherical particles at low particle volumes is negligibly small. The particle effects on the RMS velocities at Re_τ = 395 are significantly smaller than those at Re_τ = 180, despite qualitatively the same effects, i.e., the presence of particles decreases the maximum streamwise RMS velocity near the wall via weakening the large-scale streamwise vortices,and increases the transverse and spanwise RMS velocities in the vicinity of the wall by inducing smaller-scale vortices. The effects of the particles on the PDFs of the fluid fluctuating velocities normalized with the RMS velocities are small, regardless of the particle size, the particle volume fraction, and the Reynolds number. 展开更多
关键词 TURBULENT channel flow finite-size particle direct numerical simulation(DNS)
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Electronically Conductive Metal−Organic Framework With Photoelectric and Photothermal Effect as a Stable Cathode for High-Temperature Photo-Assisted Zn/Sn-Air Battery
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作者 Jiangchang Chen Chuntao Yang +2 位作者 Yao Dong Ya Han Yingjian 《Carbon Energy》 2026年第1期105-114,共10页
Rechargeable Zn/Sn-air batteries have received considerable attention as promising energy storage devices.However,the electrochemical performance of these batteries is significantly constrained by the sluggish electro... Rechargeable Zn/Sn-air batteries have received considerable attention as promising energy storage devices.However,the electrochemical performance of these batteries is significantly constrained by the sluggish electrocatalytic reaction kinetics at the cathode.The integration of light energy into Zn/Sn-air batteries is a promising strategy for enhancing their performance.However,the photothermal and photoelectric effects generate heat in the battery under prolonged solar irradiation,leading to air cathode instability.This paper presents the first design and synthesis of Ni_(2)-1,5-diamino-4,8-dihydroxyanthraquinone(Ni_(2)DDA),an electronically conductiveπ-d conjugated metal-organic framework(MOF).Ni_(2)DDA exhibits both photoelectric and photothermal effects,with an optical band gap of~1.14 eV.Under illumination,Ni_(2)DDA achieves excellent oxygen evolution reaction performance(with an overpotential of 245 mV vs.reversible hydrogen electrode at 10 mA cm^(−2))and photothermal stability.These properties result from the synergy between the photoelectric and photothermal effects of Ni_(2)DDA.Upon integration into Zn/Sn-air batteries,Ni_(2)DDA ensures excellent cycling stability under light and exhibits remarkable performance in high-temperature environments up to 80℃.This study experimentally confirms the stable operation of photo-assisted Zn/Sn-air batteries under high-temperature conditions for the first time and provides novel insights into the application of electronically conductive MOFs in photoelectrocatalysis and photothermal catalysis. 展开更多
关键词 electronically conductive MOFs high temperatures photo-assisted Zn/Sn-air batteries photoelectric effects photothermal effects
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CUDA‑based GPU‑only computation for efficient tracking simulation of single and multi‑bunch collective effects
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作者 Keon Hee Kim Eun‑San Kim 《Nuclear Science and Techniques》 2026年第1期61-79,共19页
Beam-tracking simulations have been extensively utilized in the study of collective beam instabilities in circular accelerators.Traditionally,many simulation codes have relied on central processing unit(CPU)-based met... Beam-tracking simulations have been extensively utilized in the study of collective beam instabilities in circular accelerators.Traditionally,many simulation codes have relied on central processing unit(CPU)-based methods,tracking on a single CPU core,or parallelizing the computation across multiple cores via the message passing interface(MPI).Although these approaches work well for single-bunch tracking,scaling them to multiple bunches significantly increases the computational load,which often necessitates the use of a dedicated multi-CPU cluster.To address this challenge,alternative methods leveraging General-Purpose computing on Graphics Processing Units(GPGPU)have been proposed,enabling tracking studies on a standalone desktop personal computer(PC).However,frequent CPU-GPU interactions,including data transfers and synchronization operations during tracking,can introduce communication overheads,potentially reducing the overall effectiveness of GPU-based computations.In this study,we propose a novel approach that eliminates this overhead by performing the entire tracking simulation process exclusively on the GPU,thereby enabling the simultaneous processing of all bunches and their macro-particles.Specifically,we introduce MBTRACK2-CUDA,a Compute Unified Device Architecture(CUDA)ported version of MBTRACK2,which facilitates efficient tracking of single-and multi-bunch collective effects by leveraging the full GPU-resident computation. 展开更多
关键词 Code development GPU computing Collective effects
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Synergistic antibacterial effect and mechanism of benzalkonium chloride and polymyxin B against Pseudomonas aeruginosa
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作者 Caihong Wang Jiaxin Zhang +3 位作者 Tong Li Jingwei Wang Dan Xu Qiao Ma 《Journal of Environmental Sciences》 2026年第1期555-564,共10页
Benzalkonium chloride(BAC)is widely employed as a broad-spectrum biocide and has emerged as a significant environmental pollutant.Polymyxin B(PB)serves as the last-line defense for the treatment of Gram-negative patho... Benzalkonium chloride(BAC)is widely employed as a broad-spectrum biocide and has emerged as a significant environmental pollutant.Polymyxin B(PB)serves as the last-line defense for the treatment of Gram-negative pathogens.Previous studies reported that BAC-adapted Pseudomonas aeruginosa increased the tolerance to PB.Herein,we present the novel finding that the combination of BAC and PB exhibited synergistic antibacterial effects against P.aeruginosa.Time-killing assay demonstrated a significant reduction in bacterial cell viability.Scanning electron microscopy,zeta potential analysis,hydrophobicity measurements,and fluorescence probe analyses collectively revealed severe disruption of the cell envelope and membrane potential induced by the combination of BAC and PB.Transcriptomic analysis revealed that the BAC-PB combination notably downreg-ulated the expression of genes involved in lipid A modification and cell envelope production,including phoPQ,pmrAB,bamABCDE,lptABCDEG,lolB,yidC,and murJ.Additionally,the combination group exhibited augmented production of reactive oxygen species and diminished ATP synthesis.The expression of the genes associated with substance metabolism and energy generation was significantly impeded.This study provides significant implica-tions for the interactions of biocides and antibiotics on Gram-negative pathogens,while also addressing antibiotic resistance and developing the external treatment strategy for Pseudomonas-infected wounds and burns. 展开更多
关键词 Pseudomonas aeruginosa Benzalkonium chloride Polymyxin B Synergistic effect Membrane disruption
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Postoperative effective lens position and refraction changes with three different types of intraocular lens
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作者 Xi-Xia Ding Lin-Feng Xiang +5 位作者 Wen-Tao Tong Dan-Dan Wang Hong-FangZhang Ping-Jun Chang Fu-Man Yang Yun-E Zhao 《International Journal of Ophthalmology(English edition)》 2026年第2期260-265,共6页
AIM:To evaluate and compare alterations in the effective lens position(ELP)and refractive outcomes among three distinct intraocular lens(IOL)types.METHODS:Patients with cataracts were enrolled and allocated to 3 group... AIM:To evaluate and compare alterations in the effective lens position(ELP)and refractive outcomes among three distinct intraocular lens(IOL)types.METHODS:Patients with cataracts were enrolled and allocated to 3 groups:Group A(implanted with the SN6CWS),Group B(implanted with the MI60),and Group C(implanted with the Aspira-aA).ELP measurements were obtained with swept-source optical coherence tomography(SS-OCT)at 1d,1wk,1mo,and 3mo postoperatively.Subjective refraction assessments were conducted at 1wk,1mo,and 3mo following surgery.RESULTS:The study included 189 eyes of 150 cataract patients(66 males).There were 77 eyes in Group A,55 eyes in Group B,and 57 eyes in Group C.The root mean square of the ELP(ELPRMS)within the initial 3mo was significantly lower for Group A than for Groups B and C.Refractive changes within Group A were not significant across the time points of 1wk,1mo,and 3mo.Conversely,both Group B and Group C demonstrated statistically significant shifts toward hyperopia from 1wk to 3mo postsurgery.CONCLUSION:Among the three IOLs examined,the SN6CWS IOL showes the greatest stability during the first 3mo postoperatively.Between 1wk and 3mo after surgery,notable hyperopic shifts are evident in eyes implanted with the MI60 and Aspira-aA IOLs,whereas refractive outcomes remain relatively constant in eyes implanted with SN6CWS IOLs. 展开更多
关键词 effective lens position REFRACTION intraocular lens swept-source optical coherence tomography
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Effect of Thermoelectric Cooler Arrangements on Thermal Performance and Energy Saving in Electronic Applications:An Experimental Study
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作者 M.N.Abd-Al Ameer Iman S.Kareem Ali A.Ismaeel 《Energy Engineering》 2026年第1期511-526,共16页
Electrical and electronic devices face significant challenges in heatmanagement due to their compact size and high heat flux,which negatively impact performance and reliability.Conventional coolingmethods,such as forc... Electrical and electronic devices face significant challenges in heatmanagement due to their compact size and high heat flux,which negatively impact performance and reliability.Conventional coolingmethods,such as forced air cooling,often struggle to transfer heat efficiently.In contrast,thermoelectric coolers(TECs)provide an innovative active cooling solution to meet growing thermal management demands.In this research,a refrigerant based on mono ethylene glycol and distilled water was used instead of using gases,in addition to using thermoelectric cooling units instead of using a compressor in traditional refrigeration systems.This study evaluates the performance of a Peltierbased thermalmanagement systemby analyzing the effects of using two,three,and four Peltiermodules on cooling rates,power consumption,temperature reduction,and system efficiency.Experimental results indicate that increasing the number of Peltier modules significantly enhances cooling performance.The four-module system achieved an optimal balance between cooling speed and energy efficiency,reducing the temperature of a liquidmixture(30% mono ethylene glycol+70% distilled water plus laser dyes)to 8℃ in just 17 min.It demonstrated a cooling rate of 0.794℃/min and a high coefficient of performance(COP)of 1.2 while consuming less energy than the two-and three-module systems.Furthermore,the study revealed that increasing the number of modules led to faster air cooling and improved temperature reduction.These findings highlight the importance of selecting the optimal number of Peltier modules to enhance efficiency and cooling speed whileminimizing energy consumption.This makes TEC technology a sustainable and effective solution for applications requiring rapid and reliable thermal management. 展开更多
关键词 Energy consumption mono ethylene glycol Peltier effect performance factor(COP)
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Magnetic Properties and Kondo Effect in Ce_(3)TiBi_(5) under High Pressure
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作者 L.C.Fu W.J.Cheng +11 位作者 L.C.Shi B.S.Min Y.Peng J.Zhang J.Song Z.Deng J.F.Zhao Y.Liu J.L.Zhu J.F.Zhang X.C.Wang C.Q.Jin 《Chinese Physics Letters》 2026年第1期184-197,共14页
The magnetic properties and Kondo effect in Ce3TiBi5 with a quasi-one-dimensional structure were investigated using in situ high-pressure resistivity measurements up to 48 GPa.At ambient pressure,Ce_(3)TiBi_(5) underg... The magnetic properties and Kondo effect in Ce3TiBi5 with a quasi-one-dimensional structure were investigated using in situ high-pressure resistivity measurements up to 48 GPa.At ambient pressure,Ce_(3)TiBi_(5) undergoes an antiferromagnetic(AFM)transition at T_(N)∼5 K.Under high pressures within 8.9 GPa,we find that Kondo scattering contributes differently to the high-temperature resistance,R(T),depending on the applied current direction,demonstrating a significantly anisotropic Kondo effect.The complete P–T phase diagram has been constructed,in which the pressure dependence of T_(N) exhibits a dome-like shape.The AFM order remains robust under pressure,even when the coherence temperature T^(*) far exceeds 300 K.We attribute the observed anisotropic Kondo effect and the robust AFM to the underlying anisotropy in electronic hybridization under high pressure. 展开更多
关键词 magnetic properties resistivity measurements high pressure kondo effect kondo effectthe kondo scattering Ce TbI
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Investigation of natural and anthropogenic effects on aerosols optical properties over the Western Pacific ocean by the research vessel KEXUE
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作者 Jinyuan Xin Yining Ma +6 位作者 Xiangguang Zhang Yongjing Ma Xiaoyan Wu Fangkun Wu Quan Liu Yilong Lyu Jiawei Jiang 《Journal of Environmental Sciences》 2026年第1期596-605,共10页
In winter 2018,an aerosol physicochemical experiment was conducted in the Western Pacific Ocean(WPO)aboard the Research Vessel KEXUE of Chinese Academy of Sciences.This study systematically investigated both natural a... In winter 2018,an aerosol physicochemical experiment was conducted in the Western Pacific Ocean(WPO)aboard the Research Vessel KEXUE of Chinese Academy of Sciences.This study systematically investigated both natural and anthropogenic effects on marine aerosols optical properties,as well as the applicability of multi-satellite products and IMPROVE equation.The averaged aerosol optical depth(AOD500 nm)was 0.31±0.16 andÅngström exponent440–675 nm was 0.29±0.30.In offshore China,significant anthropogenic emissions affected the marine environment.In remote WPO,dust aerosols transported from northern China,Siberia,Central Asia,and those settling from the upper troposphere originating from north Africa,Arabian peninsula,and western India,were dominant.The spatial trends of AOD were opposite in the mid-latitude and southern seas of WPO.The highest AOD,0.32±0.23,appeared along the coast of South Asia at mid-latitude,decreasing from offshore seas to remote oceans.In low-latitude and equatorial seas,AOD significantly increased from coast to remote oceans.Ångström exponent dropped significantly from the coast to remote oceans as anthropogenic influence diminished across the entire WPO.Correlation analysis showed that both MODIS-C6 and Himawari AOD prod-ucts showed similar applicability in coastal urban areas,while Himawari AOD is highly recommended for coastal background and marine environment due to its finer resolution.The extinction coefficient derived from PM_(2.5) chemical compositions using IMPROVE algorithm exhibited a significant correlation(R^(2)=0.58)with the con-currently measured AOD in the absence of long-distance transport,suggesting that the IMPROVE is a reasonable proxy of the columnar average of marine aerosol extinctions free from transport influences. 展开更多
关键词 Aerosol optical properties Natural and anthropogenic effects Improve algorithm Ship-borne experiment Western Pacific Ocean
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Dynamic fracture behavior and coupled impact effect of as-cast W-Zr-Ti energetic structural material
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作者 Yuxuan Qi Liang Mao +3 位作者 Chunlan Jiang Guitao Liu Kongxun Zhao Mengchen Zhang 《Defence Technology(防务技术)》 2026年第1期422-435,共14页
This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique.The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior... This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique.The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior.The specimens exhibit violent chemical reaction during the fracture process under the impact loading,and the size distribution of their residual debris follows Rosin-Rammler model.The dynamic fracture toughness is obtained by the fitting of debris length scale,approximately 1.87 MPa·m~(1/2).Microstructure observation on residual debris indicates that the failure process is determined by primary crack propagation under quasi-static compression,while it is affected by multiple cracks propagation in both particle and matrix in the case of dynamic impact.Impact test demonstrates that the novel energetic fragment performs brilliant penetration and combustion effect behind the front target,leading to the effective ignition of fuel tank.For the brittleness of as-cast W-ZrTi ESM,further study conducted bond-based peridynamic(BB-PD)C++computational code to simulate its fracture behavior during penetration.The BB-PD method successfully captured the fracture process and debris cloud formation of the energetic fragment.This paper explores a novel as-cast metallic ESM,and provides an available numerical avenue to the simulation of brittle energetic fragment. 展开更多
关键词 Energetic structural material Dynamic fracture behavior Coupled impact effect Mechanical property Peridynamics As-cast W-Zr-Ti alloy
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Effectiveness and Safety of Lenvatinib and Everolimus after Immune Checkpoint Inhibitors in Metastatic Renal Cell Cancer:A Systematic Review
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作者 Giacomo Iovane Luca Traman +5 位作者 Michele Maffezzoli Giuseppe Fornarini Domenico Corradi Debora Guareschi Matteo Santoni Sebastiano Buti 《Oncology Research》 2026年第1期57-70,共14页
Background:While the treatment of metastatic renal cell carcinoma(mRCC)is evolving due to immune checkpoint inhibitors(ICIs),optimal strategies for later lines of therapy have yet to be defined.The combination of lenv... Background:While the treatment of metastatic renal cell carcinoma(mRCC)is evolving due to immune checkpoint inhibitors(ICIs),optimal strategies for later lines of therapy have yet to be defined.The combination of lenvatinib and everolimus represents a viable option,and the present review aimed to summarize its activity,effectiveness,and safety.Methods:A systematic review of the literature was conducted using PubMed,targeting studies published between 2018 and 2025.Eligible studies included English-language prospective and retrospective trials reporting survival outcomes in mRCC patients treated with lenvatinib and everolimus after at least one ICI-containing regimen.Results:Nine studies met the inclusion criteria,encompassing a total of 441 patients.The lenvatinib and everolimus combination was primarily used in the third and subsequent lines of therapy.Median overall survival ranged from 7.5 to 24.5 months,while median progression-free survival was more consistent,between 6.1 and 6.7 months,except for one study reporting 12.9 months.Objective response rates varied widely(14.0%–55.7%).Adverse events of grade≥3 did not exceed the expected rate,with diarrhoea and proteinuria as the most reported events.Dose reductions and treatment discontinuations due to toxicity occurred but were generally lower than in prior pivotal trials.Conclusions:Real-world evidence suggests that lenvatinib and everolimus represent an effective and safe option after ICI failure in mRCC patients.Nevertheless,the lack of randomized phase III trials and the heterogeneity of existing studies highlight the need for more robust prospective research to guide post-ICI therapeutic strategies. 展开更多
关键词 Metastatic renal cell carcinoma(mRCC) immune checkpoint inhibitors(ICIs) lenvatinib EVEROLIMUS effectIVENESS SAFETY systematic review
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Lithium Nitrate Effects for Lithium-Based Chemical Batteries:A Review
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作者 Xianshu Wang Junru Wu +6 位作者 Huirong Wang Xiangshao Yin Zhuo Zhou Yuanyuan Huang Yelong Zhang Weishan Li Baohua Li 《Carbon Energy》 2026年第1期197-222,共26页
Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and l... Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and long-range electric vehicles.However,technical barriers such as dendrite growth and poor Li plating/stripping reversibility severely hinder the practical application of LMBs.However,lithium nitrate(LiNO_(3))is found to be able to stabilize the Li/electrolyte interface and has been used to address the above challenges.To date,considerable research efforts have been devoted toward understanding the roles of LiNO_(3) in regulating the surface properties of Li anodes and toward the development of many effective strategies.These research efforts are partially mentioned in some articles on LMBs and yet have not been reviewed systematically.To fill this gap,we discuss the recent advances in fundamental and technological research on LiNO_(3) and its derivatives for improving the performances of LMBs,particularly for Li-sulfur(S),Li-oxygen(O),and Li-Li-containing transition-metal oxide(LTMO)batteries,as well as LiNO_(3)-containing recipes for precursors in battery materials and interphase fabrication.This review pays attention to the effects of LiNO_(3) in lithium-based batteries,aiming to provide scientific guidance for the optimization of electrode/electrolyte interfaces and enrich the design of advanced LMBs. 展开更多
关键词 effects and mechanisms LiNO_(3)derivatives LiNO_(3)-containing recipes lithium metal anode Lithium nitrate basis lithium-based chemical batteries
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Modeling of finite-size droplets and particles in multiphase flows 被引量:3
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作者 Prashant Khare Shanwu Wang Vigor Yang 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第4期974-982,共9页
The conventional point-particle approach for treating the dispersed phase in a continuous flowfield is extended by taking into account the effect of finite particle size, using a Gaussian interpolation from Lagrangian... The conventional point-particle approach for treating the dispersed phase in a continuous flowfield is extended by taking into account the effect of finite particle size, using a Gaussian interpolation from Lagrangian points to the Eulerian field.The inter-phase exchange terms in the conservation equations are distributed over the volume encompassing the particle size, as opposed to the Dirac delta function generally used in the point-particle approach.The proposed approach is benchmarked against three different flow configurations in a numerical framework based on large eddy simulation(LES) turbulence closure.First, the flow over a circular cylinder is simulated for a Reynolds number of 3900 at 1 atm pressure.Results show good agreement with experimental data for the mean streamwise velocity and the vortex shedding frequency in the wake region.The calculated flowfield exhibits correct physics, which the conventional point-particle approach fails to capture.The second case deals with diesel jet injection in quiescent environment over a pressure range of 1.1–5.0 MPa.The calculated jet penetration depth closely matches measurements.It decreases with increasing chamber pressure, due to enhanced drag force in a denser fluid environment.Finally, water and acetone jet injection normal to air crossflow is studied at1 atm.The calculated jet penetration and Sauter mean diameter of liquid droplets compare very well with measurements. 展开更多
关键词 Droplets finite-size effects Large eddy simulation Multiphase flow Particle-laden flow
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Ground state of electron-doped t-t′-J model on cylinders:An investigation of finite size and boundary condition effects
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作者 Yang Shen Xiangjian Qian Mingpu Qin 《Chinese Physics B》 2025年第8期668-676,共9页
We perform a comprehensive study of the electron-doped t-t′-J model on cylinders with density matrix renormalization group(DMRG).We conduct a systematic study on the finite-size and boundary condition effects on t-t... We perform a comprehensive study of the electron-doped t-t′-J model on cylinders with density matrix renormalization group(DMRG).We conduct a systematic study on the finite-size and boundary condition effects on t-t′-J model on cylinders.Periodic and anti-periodic boundary conditions are implemented along the circumference direction,with the system’s width extending up to as large as 8 lattice units.We study doping levels of 1/6,1/8,and 1/12,which represent the most interesting region in the phase diagram of electron-doped cuprates.We find that for width-4 and width-6 systems,the ground state for fixed doping switches between anti-ferromagnetic Neel state and stripe state under different boundary conditions and system widths,indicating the presence of large finite size effect in the t-t′-J model.We also have a careful analysis of the d-wave pairing correlations which also change quantitatively with boundary conditions and widths of the system.However,the pairing correlations are enhanced when the system becomes wider for all dopings,suggesting the existence of possible long-range superconducting order in the thermodynamic limit.The width-8 results are found to be dependent on the starting state in the DMRG calculation for the kept states we can reach.For the width-8 system,only Neel(stripe)state can be stabilized in DMRG calculation for 1/12(1/6)doping,while both stripe and Neel states are stable in the DMRG sweep for 1/8 doping,regardless of the boundary conditions.These results indicate that 1/8 doping is likely to lie on the boundary of a phase transition between the Neel phase with lower doping and the stripe phase with higher doping,consistent with the previous study.The sensitivity of the ground state on boundary conditions and size observed for narrow systems is similar to that found in the t′-Hubbard model,where the t′term introduces frustration and makes the stripe state fragile.The study of different boundary conditions provides a useful tool to check the finite size effect in the future DMRG calculations. 展开更多
关键词 t-t0-J model finite-size effect boundary conditions DMRG SUPERCONDUCTIVITY
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Transition and self-sustained turbulence in dilute suspensions of finite-size particles 被引量:1
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作者 I.Lashgari F.Picano L.Brandt 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2015年第3期121-125,共5页
We study the transition to turbulence of channel flow of finite-size particle suspensions at low volume fraction, i.e., φ ≈0.001. The critical Reynolds number above which turbulence is sustained reduces to Re ≈ 167... We study the transition to turbulence of channel flow of finite-size particle suspensions at low volume fraction, i.e., φ ≈0.001. The critical Reynolds number above which turbulence is sustained reduces to Re ≈ 1675, in the presence of few particles, independently of the initial condition, a value lower than that of the corresponding single-phase flow, i.e., Re ≈1775. In the dilute suspension, the initial arrangement of the particles is important to trigger the transition at a fixed Reynolds number and particle volume fraction. As in single phase flows, streamwise elongated disturbances are initially induced in the flow. If particles can induce oblique disturbances with high enough energy within a certain time, the streaks breakdown, flow experiences the transition to turbulence and the particle trajectories become chaotic, Otherwise, the streaks decay in time and the particles immigrate towards the channel core in a laminar flow. 展开更多
关键词 Flow transition Suspension finite-size particles Lift-up effect
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Finite-size analysis of continuous-variable quantum key distribution with entanglement in the middle 被引量:1
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作者 Ying Guo Yu Su +2 位作者 Jian Zhou Ling Zhang Duan Huang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第1期232-239,共8页
Continuous-variable quantum key distribution(CVQKD) protocols with entanglement in the middle(EM) enable long maximal transmission distances for quantum communications. For the security analysis of the protocols, it i... Continuous-variable quantum key distribution(CVQKD) protocols with entanglement in the middle(EM) enable long maximal transmission distances for quantum communications. For the security analysis of the protocols, it is usually assumed that Eve performs collective Gaussian attacks and there is a lack of finite-size analysis of the protocols. However,in this paper we consider the finite-size regime of the EM-based CVQKD protocols by exposing the protocol to collective attacks and coherent attacks. We differentiate between the collective attacks and the coherent attacks while comparing asymptotic key rate and the key rate in the finite-size scenarios. Moreover, both symmetric and asymmetric configurations are collated in a contrastive analysis. As expected, the derived results in the finite-size scenarios are less useful than those acquired in the asymptotic regime. Nevertheless, we find that CVQKD with entanglement in the middle is capable of providing fully secure secret keys taking the finite-size effects into account with transmission distances of more than 30 km. 展开更多
关键词 continuous-variable quantum key distribution ENTANGLEMENT in the middle finite-size coherent attack
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Assessment of force models on finite-sized particles at finite Reynolds numbers 被引量:1
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作者 Ruyang LI Weixi HUANG +1 位作者 LihaoZHAO ChunxiaoXU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第6期953-966,共14页
Finite-sized inertial spherical particles are fully-resolved with the immersed boundary projection method(IBPM)in the turbulent open-channel flow by direct numerical simulation(DNS).The accuracy of the particle surfac... Finite-sized inertial spherical particles are fully-resolved with the immersed boundary projection method(IBPM)in the turbulent open-channel flow by direct numerical simulation(DNS).The accuracy of the particle surface force models is investigated in comparison with the total force obtained via the fully-resolved method.The results show that the steady-state resistance only performs well in the streamwise direction,while the fluid acceleration force,the added-mass force,and the shear-induced Saffman lift can effectively compensate for the large-amplitude and high-frequency characteristics of the particle surface forces,especially for the wall-normal and spanwise components.The modified steady-state resistance with the correction effects of the acceleration and the fluid shear can better represent the overall forces imposed on the particles,and it is a preferable choice of the surface force model in the Lagrangian point-particle method. 展开更多
关键词 finite-sized particle immersed boundary projection method(IBPM) force model Saffman lift
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Critical Behaviors and Finite-Size Scaling of Principal Fluctuation Modes in Complex Systems
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作者 李晓腾 陈晓松 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第9期355-362,共8页
Complex systems consisting of N agents can be investigated from the aspect of principal fluctuation modes of agents. From the correlations between agents, an N × N correlation matrix C can be obtained. The princi... Complex systems consisting of N agents can be investigated from the aspect of principal fluctuation modes of agents. From the correlations between agents, an N × N correlation matrix C can be obtained. The principal fluctuation modes are defined by the eigenvectors of C. Near the critical point of a complex system, we anticipate that the principal fluctuation modes have the critical behaviors similar to that of the susceptibity. With the Ising model on a two-dimensional square lattice as an example, the critical behaviors of principal fluctuation modes have been studied. The eigenvalues of the first 9 principal fluctuation modes have been invesitigated. Our Monte Carlo data demonstrate that these eigenvalues of the system with size L and the reduced temperature t follow a finite-size scaling form λn(L, t) = Lγ/νf n(t L^(1/ν)), where γ is critical exponent of susceptibility and ν is the critical exponent of the correlation length. Using eigenvalues λ1, λ2 and λ6, we get the finite-size scaling form of the second moment correlation length ξ(L, t) = Lξ(tL^(1/ν)).It is shown that the second moment correlation length in the two-dimensional square lattice is anisotropic. 展开更多
关键词 critical phenomena finite-size scaling principal fluctuation modes
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