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Entropy squeezing for a V-type three-level atom interacting with a single-mode field and passing through the amplitude damping channel with weak measurement 被引量:1
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作者 Cui-Yu Zhang Mao-Fa Fang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第1期158-163,共6页
The entropy squeezing of a V-type three-level atom interacting with a single-mode field and passing through the amplitude damping channel is investigated in detail. Our results show that when coupled to the single-mod... The entropy squeezing of a V-type three-level atom interacting with a single-mode field and passing through the amplitude damping channel is investigated in detail. Our results show that when coupled to the single-mode field, the atom in appropriate initial states can not only generate obvious entropy squeezing but also keep in the optimal squeezing state,while passing through the amplitude damping channel, the atom can generate entropy squeezing under the control of the weak measurement. Besides, it is proved again that as a measurement method for atomic squeezing, the entropy squeezing is precise and effective. Therefore our work is instructive for experiments in preparing three-level system information resource with ultra-low quantum noise. 展开更多
关键词 entropy squeezing V-type three-level atom single-mode field weak measurement
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Effects of an applied low frequency field on the dynamics of a two-level atom interacting with a single-mode field
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作者 徐勋卫 刘念华 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期343-349,共7页
The effects of an applied low frequency field on the dynamics of a two-level atom interacting with a single-mode field are investigated. It is shown that the time evolution of the atomic population is mainly controlle... The effects of an applied low frequency field on the dynamics of a two-level atom interacting with a single-mode field are investigated. It is shown that the time evolution of the atomic population is mainly controlled by the coupling constants and the frequency of the low frequency field, which leads to a low frequency modulation function for the time evolution of the upper state population. The amplitude of the modulation function becomes larger as the coupling constants increase. The frequency of the modulation function is proportional to the frequency of the low frequency field, and decreases with increasing coupling constant. 展开更多
关键词 two-level atom low frequency field single-mode field
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Cavity Field Spectra of a Cascade Three-Level Atom Interacting with a Single-Mode Field with Kerr-Like Medium
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作者 GAO Yun-Feng FENG Jian ZHANG Gui-Ming 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期131-134,共4页
The cavity field spectrum of a cascade three-level atom interacting with single-mode field with Kerr-like medium in the cavity is investigated. The numerical results for the initial field in pure number state, coheren... The cavity field spectrum of a cascade three-level atom interacting with single-mode field with Kerr-like medium in the cavity is investigated. The numerical results for the initial field in pure number state, coherent state and squeezed vacuum state are calculated, respectively. It is found that the Kerr-like medium affects the spectral structure even though the initial field is in vacuum when the atom is in upper level. In the case of strong input field, the number state spectrum shows two peaks with different heights; and the superposition state spectrum shows a multipeak structure with an equal distance of two neighboring peaks. The spectral "central frequency" shifts away from the resonant frequency with the increasing of average photon number. 展开更多
关键词 cavity field spectrum Kerr-like medium cascade three-level atom
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Quantum entanglement in the system of two two-level atoms interacting with a single-mode vacuum field 被引量:9
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作者 曾可 方卯发 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第10期2009-2013,共5页
The entanglement properties of the system of two two-level atoms interacting with a single-mode vacuum field are explored. The quantum entanglement between two two-level atoms and a single-mode vacuum field is investi... The entanglement properties of the system of two two-level atoms interacting with a single-mode vacuum field are explored. The quantum entanglement between two two-level atoms and a single-mode vacuum field is investigated by using the quantum reduced entropy; the quantum entanglement between two two-level atoms, and that between a single two-level atom and a single-mode vacuum field are studied in terms of the quantum relative entropy. The influences of the atomic dipole-dipole interaction on the quantum entanglement of the system are also discussed. Our results show that three entangled states of two atoms-field, atom-atom, and atom-field can be prepared via two two-level atoms interacting with a single-mode vacuum field. 展开更多
关键词 quantum entanglement single mode vacuum field reduced entropy relative entropy
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Steady and optimal entropy squeezing for three types of moving three-level atoms coupled with a single-mode coherent field
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作者 Wen-Jin Huang Mao-Fa Fang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第1期164-169,共6页
The entropy squeezing properties of different types of moving three-level atoms coupled with a single-mode coherent field are studied. The influences of the moving velocity and initial states of the three-level atom o... The entropy squeezing properties of different types of moving three-level atoms coupled with a single-mode coherent field are studied. The influences of the moving velocity and initial states of the three-level atom on the entropy squeezing are discussed. The results show that, the entropy squeezing properties of the three-level atom depend on its initial state, moving velocity, and the type. A stationary three-level atom can not obtain a steady entropy squeezing whatever initial conditions are chosen, while a moving three-level atom can achieve a steady and optimal entropy squeezing through choosing higher velocity and appropriate initial state. Our result provides a simple method for preparing squeezing resources with ultra-low quantum noise of the three-level atomic system without additional any complex techniques. 展开更多
关键词 entropy squeezing moving three-level atom single-mode coherent field
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The entanglement evolution of two coupling two-level atoms interacting with a single-mode vacuum field in multiphoton Tavis-Cummings model
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作者 Lu Daoming 《Engineering Sciences》 EI 2012年第1期80-85,共6页
Using multipohton Tavis-Cummings model,the entanglement evolution of two coupling two-level atoms in Bell states interacting with a single-mode vacuum field is investigated by using negativity.The influences of coupli... Using multipohton Tavis-Cummings model,the entanglement evolution of two coupling two-level atoms in Bell states interacting with a single-mode vacuum field is investigated by using negativity.The influences of coupling constants between atoms,the atomic initial states and the photon number of transition on the entanglement evolution of two coupling two-level atoms are discussed.The results obtained using the numerical method show that the entanglement of two atoms is related with coupling constants between atoms,the atomic initial states and the photon number of transition.The two-atom entanglement state will forever stay in the maximum entanglement state when the initial state is β11〉.When the initial state of two atoms is β01〉,the entanglement of two atoms displays periodic oscillation behavior.And its oscillation period decreases with increasing of coupling constant between atoms or the photon number of transition.On the other hand,when the initial state is β00〉 or β10〉,the entanglement of two atoms displays quasiperiodic oscillation behavior and its oscillation period decreases with increasing of coupling constant between atoms or the photon number of transition. 展开更多
关键词 quantum optics single-mode vacuum field two coupling two-level atoms muhiphoton ENTANGLEMENT
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Determination of optical properties of a single-mode class-A laser amplifier using the noise fluxes generated by cavity Langevin force
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作者 J Jahanpanah D H Dastjerdi A A Rahdar 《Communications in Theoretical Physics》 2025年第8期150-159,共10页
The noise feature of a single-mode class-A laser amplifier is investigated by solving the Maxwell–Bloch equations of motion in the presence of the fluctuation force of cavity Langevin.The aim is to calculate the simu... The noise feature of a single-mode class-A laser amplifier is investigated by solving the Maxwell–Bloch equations of motion in the presence of the fluctuation force of cavity Langevin.The aim is to calculate the simultaneous fluctuations that are superimposed on the amplitude and phase of the cavity electric field, as well as the atomic population inversion. The correlation function of these fluctuations yields the amplitude, phase, and spontaneous emission noise fluxes, respectively. The amplitude and spontaneous emission noise fluxes exhibit the Lorentzian profiles in both the below-threshold state and the injection-locking region of the above-threshold state. While noise is typically viewed negatively in science and engineering, this research highlights its positive role as a valuable tool for measuring the optical properties of a laser amplifier. For instance, the degree of first-order temporal coherence(DFOTC) is derived by taking the Fourier transform of the amplitude noise flux. The damping rate of DFOTC is associated with the coherence time of the light emitted by the laser amplifier. Furthermore, the uncertainty relation between noise bandwidth and coherence time is confirmed. Finally, it is demonstrated that the input pumping noise flux, together with the output amplitude and spontaneous emission noise fluxes, satisfy the principle of flux conservation. 展开更多
关键词 cavity langevin force amplitude noise flux correlation function spontaneous emission noise flux single-mode class-A laser amplifier
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Finite-time disentanglement induced by single-mode thermal field
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作者 韩峰 夏云杰 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第12期5144-5148,共5页
In this paper, we study the entanglement dynamics of atoms locally coupled to a cavity field. By studying two different models within the framework of cavity QED, we show that the so-called atomic entanglement sudden ... In this paper, we study the entanglement dynamics of atoms locally coupled to a cavity field. By studying two different models within the framework of cavity QED, we show that the so-called atomic entanglement sudden death always occurs if initially the cavity field is in the thermal state, in clear contrast with that in the vacuum state where the same entanglement decay is in infinite time. 展开更多
关键词 entanglement sudden death thermal fields
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Strange Attractors in the Resonance Interaction of Two-State Atoms with Single-Mode Laser Field
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作者 Xue Xinfeng Zhang Yuesheng Yao Duanzheng 《Wuhan University Journal of Natural Sciences》 EI CAS 1998年第1期32-34,共3页
The resonance interaction of two-state atoms with single mode field is described theoretically by using the semi-classical theory and Jaynes-Cummings model. The nonlinear characteristics of this system are calculated ... The resonance interaction of two-state atoms with single mode field is described theoretically by using the semi-classical theory and Jaynes-Cummings model. The nonlinear characteristics of this system are calculated by using FFT and Runge-Kutta methods. The chaotic strange attractors in this system are obtained from the numerical results. 展开更多
关键词 strange attractor atoms interacting with laser field RWA
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Effects of postselected von Neumann measurement on the properties of single-mode radiation fields
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作者 Yusuf Turek 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第9期199-211,共13页
Postselected von Neumann measurement characterized by postselection and weak value has been found to possess potential applications in quantum metrology and solved plenty of fundamental problems in quantum theory. As ... Postselected von Neumann measurement characterized by postselection and weak value has been found to possess potential applications in quantum metrology and solved plenty of fundamental problems in quantum theory. As an application of this new measurement technique in quantum optics and quantum information processing, its effects on the features of single-mode radiation fields such as coherent state, squeezed vacuum state and Schrödinger cat sate are investigated by considering full-order effects of unitary evolution. The results show that the conditional probabilities of finding photons, second-order correlation functions, Qm-factors and squeezing effects of those states after the postselected measurement is significantly changed are comparable with the corresponding initial pointer states. 展开更多
关键词 radiation field postselection weak value statistical properties squeezing parameter
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Doping dependence of resistivity,upper critical field and its anisotropy in overdoped Ba_(1-x)K_(x)Fe_(2)As_(2)(x=0.6-1)single crystals
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作者 Ke Shi Wenshan Hong +10 位作者 Yang Li Minjie Zhang Yongqi Han Yu Zhao Jiating Wu Ze Wang Langsheng Ling Chuanying Xi Li Pi Huiqian Luo Zhaosheng Wang 《Chinese Physics B》 2026年第1期272-278,共7页
Temperature-dependent resistivity,upper critical field H_(c2)and its anisotropy in overdoped superconducting Ba_(1-x)K_x Fe_2As_2(x=0.6-1)single crystals have been measured in steady magnetic fields up to 44 T and low... Temperature-dependent resistivity,upper critical field H_(c2)and its anisotropy in overdoped superconducting Ba_(1-x)K_x Fe_2As_2(x=0.6-1)single crystals have been measured in steady magnetic fields up to 44 T and low temperatures down to 0.4 K.Analysis using both the quadratic term and power-law fitting demonstrates that the in-plane resistivityρ_(ab)(T)progressively approaches the Fermi-liquid T~2behavior with increasing K doping and reaches a saturation plateau at x≈0.8.The temperature dependence of both H_(c2)^(ab)and H^(c)_(c2)follows the Werthamer-Helfand-Hohenberg model,incorporating orbital and spin paramagnetic effects.For x≤0.8,the orbital effect dominates for H ab,while the Pauli paramagnetic effect prevails for H c.For x>0.8,the Pauli paramagnetic effect becomes dominant in both crystallographic directions.The anisotropy of H_(c2)(0)exhibits a discontinuity in its dependence on K doping concentration with a significant enhancement at x=0.8 and a maximum at x=0.9.These experimental results indicate that the electron correlation effect is enhanced in the heavily overdoped Ba_(1-x)K_(x)Fe_(2)As_(2)system where the underlying symmetries are broken due to the Fermi surface reconstruction before x=0.9. 展开更多
关键词 BaK122 single crystals high magnetic fields upper critical field H_(c2) MAGNETORESISTANCE
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Tear proteomics reveals biomarkers for visual field progression in normal-tension glaucoma
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作者 Le-Wei Tang Hui-Yan Mao +5 位作者 Mei-Min Lin Si Zhu Qiang-Jie Huang De-Fu Chen Wei-He Zhou Yuan-Bo Liang 《International Journal of Ophthalmology(English edition)》 2026年第1期1-10,共10页
AIM:To identify early biomarkers associated with glaucomatous visual field(VF)progression in patients with normal-tension glaucoma(NTG).METHODS:This study included patients were divided into two groups based on diseas... AIM:To identify early biomarkers associated with glaucomatous visual field(VF)progression in patients with normal-tension glaucoma(NTG).METHODS:This study included patients were divided into two groups based on disease progression status.Tear samples were collected for proteomic analysis.Dataindependent acquisition(DIA)mass spectrometry combined with bioinformatic analyses was performed to identify and validate potential protein biomarkers for NTG progression.Additionally,differentially expressed proteins(DEPs)were evaluated using mediating effect models and receiver operating characteristic(ROC)curve analysis.RESULTS:A total of 19 patients(20 eyes)with NTG participated in this study,including 10 patients(4 males and 6 females;10 eyes)in the progression group with mean age of 67.70±9.03y and 10 patients(4 males and 6 females;10 eyes)in the non-progression group with mean age of 68.60±7.58y.A total of 158 significantly differentially expressed proteins were detected.UniProt database annotation identified 3 upregulated proteins and 12 downregulated proteins.Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis showed that these DEPs were mainly enriched in pathways such as oocyte meiosis.Gene Ontology(GO)enrichment analysis revealed functional clusters related to cellular processes.Weighted gene coexpression network analysis(WGCNA)indicated that the core proteins were primarily involved in the neurodegenerationmultiple diseases pathway and cellular processes.Mediating effect analysis identified PRDX4(L)as a potential protein biomarker.ROC curve analysis showed that GNAI1 had the largest area under the curve(AUC=0.889).CONCLUSION:This study identifies 15 differentially expressed proteins in the tear fluid of NTG patients,including PRDX4(L).PRDX4(L)plays a key role in oxidative stress. 展开更多
关键词 normal-tension glaucoma TEARS PROTEOMICS biomarkers visual field progression
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Ultrasound/magnetic field dual-responsive Fe_(3)O_(4)/glucose oxidase catalytic microbubbles for enhanced bacterial biofilm elimination
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作者 Chi Zhang Dou Wang +6 位作者 Liang Lu Feng-Jiao Xu Fan-Sen Xu Xuan Wu Xiao-Xiao Xu Xiao Li Li-Hui Yuwen 《Biomedical Engineering Communications》 2026年第1期4-12,共9页
Background:The bacterial biofilm poses a significant challenge to traditional antibiotic therapy.There is a great need to develop novel antibiofilm agents combined with biofilm disrupting and bacteria-killing without ... Background:The bacterial biofilm poses a significant challenge to traditional antibiotic therapy.There is a great need to develop novel antibiofilm agents combined with biofilm disrupting and bacteria-killing without the dependence of antibiotic.Methods:Herein,we prepared ultrasound/magnetic field-responsive ferroferric oxide nanoparticles(Fe_(3)O_(4))/glucose oxidase microbubbles(FGMB)to form a cascade catalytic system for effective removing methicillin-resistant Staphylococcus aureus biofilms.FGMB were prepared through interfacial self-assembly of Fe_(3)O_(4) nanoparticles(NPs)and glucose oxidase(GOx)at the gas-liquid interface stabilized by surfactants.Under ultrasound/magnetic field stimulation,FGMB disrupted biofilm architecture through microbubble collapse-induced microjets and magnetically driven displacement.Simultaneously,ultrasound-triggered rupture of FGMB released GOx and Fe_(3)O_(4) NPs.Glucose can be oxidized by GOx to generate gluconic acid and hydrogen peroxide which was subsequently catalyzed into hydroxyl radicals by Fe_(3)O_(4) NPs,enabling chemical eradication of biofilm-embedded bacteria.Results:Optical microscopy images demonstrated that FGMB have spherical structure with average size of approximately 17μm.FGMB showed a 65.4%decrease in methicillin-resistant Staphylococcus aureus biofilm biomass and 1.1 log bacterial inactivation efficiency(91.2%),suggesting effective biofilm elimination.In vitro experimental results also indicate that FGMB have good biocompatibility.Conclusion:This antibiofilm strategy integrated dual modes of physical biofilm disruption with chemical bacteria-killing shows great potential as a versatile,non-resistant strategy for bacterial biofilm elimination. 展开更多
关键词 bacterial biofilm ULTRASOUND magnetic field catalytic microbubbles mechanical disruption chemical degradation
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Electric-Field-Driven Generative Nanoimprinting for Tilted Metasurface Nanostructures
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作者 Yu Fan Chunhui Wang +6 位作者 Hongmiao Tian Xiaoming Chen Ben QLi Zhaomin Wang Xiangming Li Xiaoliang Chen Jinyou Shao 《Nano-Micro Letters》 2026年第1期290-305,共16页
Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is p... Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is proposed.The electric field applied between the template and the substrate drives the contact,tilting,filling,and holding processes.By accurately controlling the introduced included angle between the flexible template and the substrate,tilted nanostructures with a controllable angle are imprinted onto the substrate,although they are vertical on the template.By flexibly adjusting the electric field intensity and the included angle,large-area uniform-tilted,gradient-tilted,and high-angle-tilted nanostructures are fabricated.In contrast to traditional replication,the morphology of the nanoimprinting structure is extended to customized control.This work provides a cost-effective,efficient,and versatile technology for the fabrication of various large-area tilted metasurface structures.As an illustration,a tilted nanograting with a high coupling efficiency is fabricated and integrated into augmented reality displays,demonstrating superior imaging quality. 展开更多
关键词 Generative nanoimprinting Electric field assistance Tilted metasurface structures Large-area fabrication
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Optical design of wide-field and broadband light field camera for high-precision optical surface defect detection
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作者 Chengchen Zhou Yukun Wang +7 位作者 Yue Ding Dacheng Wang Jiucheng Nie Jialong Li Zhixi Li Zheng Zhou Shuangshuang Zhang Xiaokun Wang 《Astronomical Techniques and Instruments》 2026年第1期64-74,共11页
To address the challenges of high-precision optical surface defect detection,we propose a novel design for a wide-field and broadband light field camera in this work.The proposed system can achieve a 50°field of ... To address the challenges of high-precision optical surface defect detection,we propose a novel design for a wide-field and broadband light field camera in this work.The proposed system can achieve a 50°field of view and operates at both visible and near-infrared wavelengths.Using the principles of light field imaging,the proposed design enables 3D reconstruction of optical surfaces,thus enabling vertical surface height measurements with enhanced accuracy.Using Zemax-based simulations,we evaluate the system’s modulation transfer function,its optical aberrations,and its tolerance to shape variations through Zernike coefficient adjustments.The results demonstrate that this camera can achieve the required spatial resolution while also maintaining high imaging quality and thus offers a promising solution for advanced optical surface defect inspection. 展开更多
关键词 Optical design Defect detection Wide-field camera Broadband light field camera
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Magnetic field enhanced electrocatalytic oxygen evolution of CoFe_(2)O_(4) with tunable oxygen vacancy concentrations
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作者 Xiangyang Zou Ping Guo +2 位作者 Yuanyuan Zhang Feng Gao Ping Xu 《Chinese Chemical Letters》 2026年第1期671-677,共7页
Magnetic field-driven spin polarization modulation has emerged as an effective way to boost the electrocatalytic oxygen evolution reaction(OER).However,the correlation among catalyst structure,magnetic property,and ma... Magnetic field-driven spin polarization modulation has emerged as an effective way to boost the electrocatalytic oxygen evolution reaction(OER).However,the correlation among catalyst structure,magnetic property,and magnetic field enhanced-electrochemical activity remains to be fully elucidated.Herein,single-domain CoFe_(2)O_(4) catalysts with tunable oxygen vacancies(CFO-V_(O)) were synthesized to probe how V_(O) mediates magnetism and OER activity under magnetic field.The introduction of V_(O) can simultaneously modulate saturation magnetization(M_(s)) and coercivity(H_(c)),where the increased M_(s) dominates the magnetic field-enhanced OER activity.Under a 14,000 G magnetic field,the optimized CFO-V_(O) exhibits up to 16.1 % reduction in overpotential and 365 % enhancement in magnetocurrent(MC).Electrochemical analyses and post-OER characterization reveal that the magnetic field synergistically improves OER kinetics through lattice distortion induction,magnetohydrodynamic effect,and spin charge transfer effect.Importantly,the magnetic field promotes additional Co^(3+) generation to compensate for charge imbalance caused by V_(O) filling,maintaining dynamic equilibrium of V_(O) and effective reactant adsorption-conversion processes.This work unveils the synergistic mechanism of V_(O) and magnetic parameters for enhancing OER performance under the magnetic field,providing new insights into the design of high-efficiency spinregulated OER catalysts. 展开更多
关键词 Spinel oxide Oxygen vacancy Magnetic field Magnetic property Oxygen evolution reaction
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Multi-energy field coupling analysis and experimental validation of picosecond laser drilling assisted by ultrasonic shock-induced water flow
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作者 Pengfei Ouyang Yang Liu +7 位作者 Zhaoyang Zhang Xiaolei Chen Yufeng Wang Hao Zhu Kun Xu Jingtao Wang Xiankai Meng Shu Huang 《Defence Technology(防务技术)》 2026年第1期130-154,共25页
The latest generation of aero engines has set higher standards for thrust-to-weight ratio and energy conversion efficiency,making it imperative to address the challenge of efficiently and accurately machining film coo... The latest generation of aero engines has set higher standards for thrust-to-weight ratio and energy conversion efficiency,making it imperative to address the challenge of efficiently and accurately machining film cooling holes.It has been demonstrated that conventional long-pulse lasers are incapable of meeting the elevated quality surface finish requirements for these holes,a consequence of the severe thermal defects.The employment of backside water-assisted laser drilling technology confers a number of distinct advantages in terms of mitigating laser thermal damage,thus representing a highly promising solution to this challenge.However,significant accumulation of bubbles and machining products during the backside water-assisted laser drilling process has been demonstrated to have a detrimental effect on laser transmission and machining stability,thereby reducing machining quality.In order to surmount these challenges,a novel method has been proposed,namely an ultrasonic shock water flow-assisted picosecond laser drilling technique.Numerical models for ultrasonic acoustic streaming and particle tracking for machining product transport have been established to investigate the mechanism.The simulation results demonstrated that the majority of the machining products could rapidly move away from the machining area because of the action of acoustic streaming,thereby avoiding the accumulation of bubbles and products.Subsequent analysis,comparing the process performance in micro-hole machining,confirmed that the ultrasonic field could effectively eliminate bubble and chip accumulation,thus significantly improving micro-hole quality.Furthermore,the impact of ultrasonic and laser parameters on micro-hole quality under varying machining methods was thoroughly investigated.The findings demonstrated that the novel methodology outlined in this study yielded superior-quality micro-holes at elevated ultrasonic and laser power levels,in conjunction with reduced laser frequency and scanning velocity.The taper of the micro-holes produced by the new method was reduced by more than 25%compared with the other conventional methods. 展开更多
关键词 Ultrasonic vibration Water assisted laser drilling Multi-energy field composite Precision manufacturing
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Reconstructed organic rice fields:Effects on soil organic carbon,total nitrogen,their mineralization,and rice yield in Japanese Andosols
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作者 Valensi Kautsar Takamori Kanno +5 位作者 Kaho Sakai Riza Kurnia Sabri Keitaro Tawaraya Kazunobu Toriyama Kazuhiko Kobayashi Weiguo Cheng 《Journal of Integrative Agriculture》 2026年第2期493-500,共8页
To examine the impact of anthropogenic land reconstruction,particularly the consolidation of small terraces into larger fields,on soil organic carbon(SOC),total nitrogen(TN)dynamics,rice yield,and its components,soil ... To examine the impact of anthropogenic land reconstruction,particularly the consolidation of small terraces into larger fields,on soil organic carbon(SOC),total nitrogen(TN)dynamics,rice yield,and its components,soil and plant samples were collected from seven newly reconstructed fields in Japanese Andosols in Tochigi,Japan.Samples were obtained from both the former low-and high-elevation sides within each field plot.During harvest season,nine rice plants were randomly selected from each plot(0.675 m^(2),comprising 3 rows and 3 hills per row),collected from a 3-m stretch along both the east(former low side)and west(former high side)ridges.Soil cores were collected from identical plots at two depths(0–15 and 15–30 cm)and combined into one composite sample per layer.Rice plant samples were air-dried for two weeks until reaching constant moisture content,after which stems and ears were separated and weighed to determine biomass,yield,yield components,and nitrogen uptake.This indicated that land reconstruction significantly affected rice yield and its components between the two sides of all field plots.SOC,TN,and their decomposition following land reconstruction showed notable changes,especially in the 15–30 cm subsurface soil layer.Additionally,grain weight demonstrated significant correlation with SOC,TN,and carbon decomposition in both the 0–15 and 15–30 cm layers,indicating that soil fertility to a depth of 30 cm was crucial for rice productivity after land reconstruction. 展开更多
关键词 Japanese Andosols different soil layers organic rice farming reconstructed fields rice yield
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Beyond superhalogen assembly:Field-driven hyperhalogen design via dual-external-field cooperativity
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作者 Ao-Hua Wang Jun Li +5 位作者 Shi-Hu Du Jia Liu Yao Zhang Muhammad Bilal Ahmed Siddique Jing Chen Shi-Bo Cheng 《Chinese Chemical Letters》 2026年第1期656-660,共5页
Traditional strategies for designing hyperhalogens,superatoms with exceptional electron-withdrawing capacity,rely on complex superhalogen assembly,posing significant experimental challenges.Here,we introduce a non-inv... Traditional strategies for designing hyperhalogens,superatoms with exceptional electron-withdrawing capacity,rely on complex superhalogen assembly,posing significant experimental challenges.Here,we introduce a non-invasive dual external field(DEF) approach combining solvent effects and an oriented external electric field(OEEF) to construct hyperhalogens,as demonstrated by density functional theory(DFT) calculations.Our DEF strategy proves versatile,successfully designing hyperhalogens not only in simplified Ag_n^(-) model systems but also in the experimentally synthesized Ag_(25) nanocluster.Using the 3D Ag_(19)^(-) structure as a model,we further reveal the DEF's pivotal role in O_(2) activation,where solvent-OEEF synergy induces tunable O-O bond elongation and charge transfer,proportional to field strength.Our findings establish a field-driven paradigm for hyperhalogen design that preserves native cluster composition,providing a theoretical foundation for tailoring high-performance catalysts through precise activesite modulation. 展开更多
关键词 Hyperhalogens Dual external fields Silver clusters O_(2)activation Charge transfer
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Visual field prediction using K-means clustering in patients with primary open angle glaucoma
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作者 Junyoung Lee Jihun Kim +5 位作者 Hwayoung Kim Sangwoo Moon EunAh Kim Sanghun Jeong Hojin Yang Jiwoong Lee 《International Journal of Ophthalmology(English edition)》 2026年第1期63-68,共6页
AIM:To evaluate long-term visual field(VF)prediction using K-means clustering in patients with primary open angle glaucoma(POAG).METHODS:Patients who underwent 24-2 VF tests≥10 were included in this study.Using 52 to... AIM:To evaluate long-term visual field(VF)prediction using K-means clustering in patients with primary open angle glaucoma(POAG).METHODS:Patients who underwent 24-2 VF tests≥10 were included in this study.Using 52 total deviation values(TDVs)from the first 10 VF tests of the training dataset,VF points were clustered into several regions using the hierarchical ordered partitioning and collapsing hybrid(HOPACH)and K-means clustering.Based on the clustering results,a linear regression analysis was applied to each clustered region of the testing dataset to predict the TDVs of the 10th VF test.Three to nine VF tests were used to predict the 10th VF test,and the prediction errors(root mean square error,RMSE)of each clustering method and pointwise linear regression(PLR)were compared.RESULTS:The training group consisted of 228 patients(mean age,54.20±14.38y;123 males and 105 females),and the testing group included 81 patients(mean age,54.88±15.22y;43 males and 38 females).All subjects were diagnosed with POAG.Fifty-two VF points were clustered into 11 and nine regions using HOPACH and K-means clustering,respectively.K-means clustering had a lower prediction error than PLR when n=1:3 and 1:4(both P≤0.003).The prediction errors of K-means clustering were lower than those of HOPACH in all sections(n=1:4 to 1:9;all P≤0.011),except for n=1:3(P=0.680).PLR outperformed K-means clustering only when n=1:8 and 1:9(both P≤0.020).CONCLUSION:K-means clustering can predict longterm VF test results more accurately in patients with POAG with limited VF data. 展开更多
关键词 K-means clustering hierarchical ordered partitioning and collapsing hybrid pointwise linear regression visual field prediction
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