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Multi-dimensional optimization of polymer-involved Li^(+)solvation enabling stable polymer plastic crystal electrolyte for long-cycle lithium metal batteries
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作者 Lianzhan Huang Yuanlong Wu +6 位作者 Piao Luo Kexin Su Xin Song Mingdong Liu Minjian Li Huiyu Song Zhiming Cui 《Journal of Energy Chemistry》 2026年第1期656-665,I0015,共11页
Succinonitrile(SN)-based polymer plastic crystal electrolytes(PPCEs)are regarded as promising candidates for lithium metal batteries but suffer from serious side reactions with Li metal.Herein,we propose a multi-dimen... Succinonitrile(SN)-based polymer plastic crystal electrolytes(PPCEs)are regarded as promising candidates for lithium metal batteries but suffer from serious side reactions with Li metal.Herein,we propose a multi-dimensional optimization strategy to alleviate the side reactions between SN and Li metal,and develop a highly stable poly-vinylethylene carbonate-based PPCE(PPCE-VEC).Moreover,we identify the intrinsic factors of multi-dimensional polymer structures on the electrolyte stability by three typical classes of polyesters.The PPCE-VEC constructed by in situ polymerization exhibits much better stability than poly-vinylene carbonate-based PPCE(PPCE-VCA)and poly-trifluoroethyl acrylate-based PPCE(PPCE-TFA),which is verified by its fewer SN-decomposition species in X-ray photoelectron spectroscopy(XPS)and outstanding full cell performance.The PPCE-VEC-enabled LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)full cell achieve 73.7%capacity retention after 1400 cycles,which outperforms PPCE-VCA-and PPCE-TFA-enabled full cells(61.9%and 46.9%).Spectral analysis and theoretical calculation reveal that the high solvation ability of the carbonyl site,flexible polymer chain,and homogeneous electrolyte phase of PPCE-VEC are favorable to maximizing competition coordination with Li^(+)to weaken the Li^(+)–SN binding and shape an anion-rich solvation structure.This optimized polymer-involved Li^(+)solvation enhances SN stability and facilitates the formation of B/F enriched solid-electrolyte interphase(SEI),thus significantly improving PPCE stability. 展开更多
关键词 SUCCINONITRILE Li metal Polymer plastic crystal electrolytes multi-dimensional polymer structures
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Learning by Comparing:Effects of Cues Focusing on Chinese-Speaking Learners’Acquisition of English Articles
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作者 Mei Yang Qiying Guo Xiaomeng Yan 《Chinese Journal of Applied Linguistics》 2026年第1期57-75,160,共20页
This study examines whether and how cues focusing enhances Chinese-speaking English learners’engagement in comparison,thereby facilitating their acquisition of English articles within xu-based comparative continuatio... This study examines whether and how cues focusing enhances Chinese-speaking English learners’engagement in comparison,thereby facilitating their acquisition of English articles within xu-based comparative continuation writing tasks.Fifty English majors from a Chinese university were randomly assigned to three groups and each group was required to complete a comparative continuation task with one of three conditions:paired cues(cues presented in pairs),randomized cues(cues presented in random order),or implicit cues(no explicit cues provided).All participants undertook pretests,posttests,and delayed tests on English article knowledge,and ten of them volunteered to take follow-up interviews.The results indicate that:1)paired cues were more effective than randomized or implicit cues in promoting the acquisition of English articles;and 2)learners in the paired cues condition produced more target-like article usage in their continuation writings compared to those in the other two conditions.The effectiveness of paired cues is attributed to an enhanced contrast effect,which prompts learners to identify similarities and differences between cues within each pair,relates cue explanations and examples with actual article usage in the reading text,and reflects upon and compares their own article productions against those in the provided reading text.The study concludes that the process of learning through continuation is fundamentally supported by learners’capacity for comparison,reinforcing its role as a core element of xu-competence. 展开更多
关键词 comparison cues focusing acquisition of English articles xu-argument
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Case studies of ion focusing in the downstream region of a modeled low Earth orbit spacecraft
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作者 Nizam Ahmad Hideyuki Usui +4 位作者 Yohei Miyake Slamet Supriadi Hanif Fakhrurroja Hilman Syaeful Alam Harry Bangkit 《Earth and Planetary Physics》 2026年第1期136-143,共8页
The effect of plasma and charged particle interaction with spacecraft in a low Earth orbit(LEO)environment leads to ion focusing and the formation of an ion void in the downstream region as a result of charging.Simula... The effect of plasma and charged particle interaction with spacecraft in a low Earth orbit(LEO)environment leads to ion focusing and the formation of an ion void in the downstream region as a result of charging.Simulations and investigations using a fixed potential imposed on the spacecraft showed the nonsignificance of geophysical parameter changes to ion focusing.Variation of the temperature ratio(T_(r))contributed only to local ion focusing and manifested as two-ion streamers dispersed at the upper and lower edges of the spacecraft-the outermost layers of the satellite structure at the top and bottom,respectively.A simulation involving changing the ambient plasma density(N_(p))also showed the formation of local ion focusing,in which ions were more concentrated as the density increased.Furthermore,auroral electron density(N_(ae))variation had no clear impact on ion focusing,as indicated by static two-ion structures in the wake field.However,variation of the object potential(ϕ)strongly affected ion focusing formation,leading to distortion of the initial ion void region behind the spacecraft.The formation of ion focusing in this study was subject to the electric field produced by the object potential and the ambipolar electric field resulting from plasma expansion in the downstream region. 展开更多
关键词 ion focusing spacecraft potential low Earth orbit environment
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FOCUS 夫妻干预对不孕症患者夫妇心理状况及生育生活质量的影响
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作者 吴姗 马瑞条 杜苓燕 《临床心身疾病杂志》 2026年第1期60-64,共5页
目的探讨FOCUS夫妻干预对不孕症患者夫妇心理状况及生育生活质量的影响。方法将96对不孕症患者及其配偶作为研究对象,随机分成研究组和对照组,各48对。对照组受试者给予常规干预措施,研究组受试者在对照组基础上给予FOCUS夫妻干预。干... 目的探讨FOCUS夫妻干预对不孕症患者夫妇心理状况及生育生活质量的影响。方法将96对不孕症患者及其配偶作为研究对象,随机分成研究组和对照组,各48对。对照组受试者给予常规干预措施,研究组受试者在对照组基础上给予FOCUS夫妻干预。干预前后,比较两组受试者心理弹性[心理弹性量表(CD-RISC)评分]、生育压力[生育压力量表(FPI)评分]、总体幸福感[总体幸福感量表(GWBS)评分]、夫妻支持应对水平[夫妻支持应对量表(DCI)评分]及生育生活质量[生育生活质量问卷评分]。结果干预后,两组患者及其配偶CD-RISC、GWBS、DCI评分较干预前升高,且研究组高于对照组(P<0.05或0.01);两组患者及其配偶FPI评分较干预前降低,且研究组低于对照组(P<0.01);两组受试者生育生活质量总优良率较干预前提高,且研究组高于对照组(P<0.05或0.01)。结论FOCUS夫妻干预应用于不孕症患者夫妇临床效果良好,可改善夫妻双方的心理状况和生育生活质量。 展开更多
关键词 不孕症 focus夫妻干预 心理状况 生育生活质量
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Composite anti-disturbance predictive control of unmanned systems with time-delay using multi-dimensional Taylor network 被引量:1
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作者 Chenlong LI Wenshuo LI Zejun ZHANG 《Chinese Journal of Aeronautics》 2025年第7期589-600,共12页
A composite anti-disturbance predictive control strategy employing a Multi-dimensional Taylor Network(MTN)is presented for unmanned systems subject to time-delay and multi-source disturbances.First,the multi-source di... A composite anti-disturbance predictive control strategy employing a Multi-dimensional Taylor Network(MTN)is presented for unmanned systems subject to time-delay and multi-source disturbances.First,the multi-source disturbances are addressed according to their specific characteristics as follows:(A)an MTN data-driven model,which is used for uncertainty description,is designed accompanied with the mechanism model to represent the unmanned systems;(B)an adaptive MTN filter is used to remove the influence of the internal disturbance;(C)an MTN disturbance observer is constructed to estimate and compensate for the influence of the external disturbance;(D)the Extended Kalman Filter(EKF)algorithm is utilized as the learning mechanism for MTNs.Second,to address the time-delay effect,a recursiveτstep-ahead MTN predictive model is designed utilizing recursive technology,aiming to mitigate the impact of time-delay,and the EKF algorithm is employed as its learning mechanism.Then,the MTN predictive control law is designed based on the quadratic performance index.By implementing the proposed composite controller to unmanned systems,simultaneous feedforward compensation and feedback suppression to the multi-source disturbances are conducted.Finally,the convergence of the MTN and the stability of the closed-loop system are established utilizing the Lyapunov theorem.Two exemplary applications of unmanned systems involving unmanned vehicle and rigid spacecraft are presented to validate the effectiveness of the proposed approach. 展开更多
关键词 multi-dimensional Taylor network Composite anti-disturbance Predictive control Unmanned systems Multi-source disturbances TIME-DELAY
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Retraced Multi-dimensional Chinese Logic System behind Chinese Medicine
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作者 Edwin C.L.Yu 《Chinese Medicine and Culture》 2025年第1期1-12,共12页
The ancient tacit knowledge behind the logic system permeated the culture and promoted numerous impactful inventions throughout the history. Traditional Chinese medicine with its effectiveness should also have stemmed... The ancient tacit knowledge behind the logic system permeated the culture and promoted numerous impactful inventions throughout the history. Traditional Chinese medicine with its effectiveness should also have stemmed out from such logic system. This article aims to rearticulate the underlying lucid multi-dimensional logic system, which faded in obscurity only because of time-out loss of the mid-right concept. Retracing this past tacit but important concept could uncover a multi-dimensional system over a point relating to all matters while capturing the central core of the matter. The seemingly unmanageable multidimensional logic was strengthened by verification processes which affirmed its further extensions, and made up the language of the people, the concepts of yin-yang(阴阳), and the development of extensions of Ba Gua(八卦) derivatives, which furthered the interpretation of the space-time properties and Chinese medicine. 展开更多
关键词 multi-dimensional logic system Traditional Chinese medicine YIN-YANG
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Effective stress dissipation by multi-dimensional architecture engineering for ultrafast and ultralong sodium storage
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作者 Man Zhang Jing Zhu +7 位作者 Qianqian Li Fenghua Zheng Sijiang Hu Youguo Huang Hongqiang Wang Xing Ou Qichang Pan Qingyu Li 《Journal of Energy Chemistry》 2025年第2期619-629,I0013,共12页
Stress accumulation is a key factor leading to sodium storage performance deterioration for NiSe_(2)-based anodes.Therefore,inhibiting the concentrated local stress during the sodiataion/desodiation process is crucial... Stress accumulation is a key factor leading to sodium storage performance deterioration for NiSe_(2)-based anodes.Therefore,inhibiting the concentrated local stress during the sodiataion/desodiation process is crucial for acquiring stable NiSe2-based materials for sodium-ion batteries(SIBs),Herein,a stress dissipation strategy driven by architecture engineering is proposed,which can achieve ultrafast and ultralong sodium storage properties.Different from the conventional sphere-like or rod-like architecture,the three-dimensional(3D)flower-like NiSe_(2)@C composite is delicately designed and assembled with onedimensional nanorods and carbon framework.More importantly,the fundamental mechanism of improved structure stability is unveiled by simulations and experimental results simultaneously.It demonstrates that this designed multidimensional flower-like architecture with dispersed nanorods can balance the structural mismatch,avoid concentrated local strain,and relax the internal stress,mainly induced by the unavoidable volume variation during the repeated conversion processes.Moreover,it can provide more Na^(+)-storage sites and multi-directional migration pathways,leading to a fast Na^(+)-migration channel with boosted reaction kinetic.As expected,it delivers superior rate performance(441 mA h g^(-1)at 5.0 A g^(-1))and long cycling stability(563 mA h g^(-1)at 1.0 A g^(-1)over 1000 cycles)for SIBs.This work provides useful insights for designing high-performance conversion-based anode materials for SIBs. 展开更多
关键词 Stress dissipation multi-dimensional architecture Structure engineering Conversion-based anodes Sodium-ion batteries
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Research on Multi-Dimensional Collaborative Strategies in Design Management,Investment Management,and Beyond from the Perspective of Whole-Process Engineering Consulting
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作者 Zexin Chen 《Journal of Architectural Research and Development》 2025年第5期21-28,共8页
This paper explores whole-process engineering consulting,including its application models in public buildings and elderly-friendly projects,such as service integration and whole lifecycle management.It also addresses ... This paper explores whole-process engineering consulting,including its application models in public buildings and elderly-friendly projects,such as service integration and whole lifecycle management.It also addresses the construction of multi-dimensional collaborative theoretical models,public space streamline organization,and other aspects,emphasizing the importance of multi-dimensional collaboration.Additionally,it highlights the role of talent cultivation and digital transformation in enhancing project efficiency. 展开更多
关键词 Whole-process engineering consulting multi-dimensional collaboration Project efficiency
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Non-invasive focusing and imaging through scattering media via a fluorescence matrix constructed from 1D speckle signals
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作者 HUANRAN XU WENJING ZHAO +2 位作者 XINLONG LIU AIPING ZHAI DONG WANG 《Photonics Research》 2025年第12期3476-3484,共9页
Non-invasive measurement of the transmission matrix(TM)enables light focusing through scattering media using linear fluorescence signals.However,its speed is limited by the frame rate of the array detector.Although ph... Non-invasive measurement of the transmission matrix(TM)enables light focusing through scattering media using linear fluorescence signals.However,its speed is limited by the frame rate of the array detector.Although photodetectors can achieve fast light focusing,they can only detect single-point signals and are ineffective in scenarios that require speckle information,such as non-invasive focusing. 展开更多
关键词 light focusing transmission matrix non invasive focusing D speckle signals fluorescence matrix linear fluorescence signalshoweverits imaging scattering media array detectoralthough
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Practical Application of the Multi-Dimensional Interactive Teaching Model in College English
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作者 Bo Sun 《Journal of Contemporary Educational Research》 2025年第10期106-111,共6页
The multi-dimensional interactive teaching model significantly enhances the effectiveness of college English instruction by emphasizing dynamic engagement between teachers and students,as well as among students themse... The multi-dimensional interactive teaching model significantly enhances the effectiveness of college English instruction by emphasizing dynamic engagement between teachers and students,as well as among students themselves.This paper explores practical strategies for implementing this model,focusing on four key aspects:deepening teachers’understanding of the model through continuous learning,innovating interactive methods such as questioning techniques and practical activities,leveraging modern technology to integrate resources and track learning progress,and establishing a communication platform that centers on student participation.By adopting these approaches,the model fosters a student-centered classroom environment,improves comprehensive English application skills,and optimizes overall teaching quality. 展开更多
关键词 multi-dimensional interactive teaching model Student-centered approach Teacher-student interaction
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Construction of the Practice System of Landscape Architecture Major Based on“Multi-dimensional Integration”
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作者 LI Yinan DING Juan +4 位作者 ZHU Yan WU Jing ZHAO Zhiyan LI Jie XIANG Cheng 《Journal of Landscape Research》 2025年第3期89-92,共4页
During the critical transformation period of landscape architecture major after the adjustment of disciplinary structure and the changes in market demand,private colleges and universities,as important places for culti... During the critical transformation period of landscape architecture major after the adjustment of disciplinary structure and the changes in market demand,private colleges and universities,as important places for cultivating local talents,have pain points such as uneven quality of teachers and students and weak innovation and practice.The practice system with“multi-dimensional Integration”integrates four dimensions:interdisciplinary integration,spatial and temporal intersection,historical inheritance,and behavioral activity,deepens the disciplinary connotation,and integrates the three elements of nature,humanity,and technology,aiming to provide a new path for private colleges and universities to cultivate application-oriented and compound talents with innovative capabilities.In terms of optimizing talent cultivation and adapting to industry changes,this system provides thinking and reference for landscape architecture major,helping the major reshape its core competitiveness and promoting educational innovation and industry development. 展开更多
关键词 Landscape architecture Practice system multi-dimensional integration”model Talent cultivation Teaching reform
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Reliability of multi-dimensional network systems with nodes having stochastic connection ranges
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作者 FU Yuqiang MA Xiaoyang ZHAO Fei 《Journal of Systems Engineering and Electronics》 2025年第4期1017-1023,共7页
This paper proposes a reliability evaluation model for a multi-dimensional network system,which has potential to be applied to the internet of things or other practical networks.A multi-dimensional network system with... This paper proposes a reliability evaluation model for a multi-dimensional network system,which has potential to be applied to the internet of things or other practical networks.A multi-dimensional network system with one source element and multiple sink elements is considered first.Each element can con-nect with other elements within a stochastic connection ranges.The system is regarded as successful as long as the source ele-ment remains connected with all sink elements.An importance measure is proposed to evaluate the performance of non-source elements.Furthermore,to calculate the system reliability and the element importance measure,a multi-valued decision diagram based approach is structured and its complexity is analyzed.Finally,a numerical example about the signal transfer station system is illustrated to analyze the system reliability and the ele-ment importance measure. 展开更多
关键词 multi-dimensional network multi-valued decision diagram stochastic connection range reliability analysis impor-tance measure.
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Sub-diffraction-limited focusing laser pulses at ultrahigh intensity via near-critical-density hollow plasma fibers
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作者 Tianqi Xu Zhuo Pan +12 位作者 Ying Gao Yulan Liang Shirui Xu Qingfan Wu Tan Song Yujia Zhang Haoran Chen Qihang Han Chenghao Hua Ziyang Peng Ke Chen Xuan Liu Wenjun Ma 《Advanced Photonics Nexus》 2025年第6期64-71,共8页
Ultra-intense electromagnetic fields exceeding 10^(23)W∕cm^(2)are enabling breakthroughs in compact laser-driven particle accelerators and revealing new quantum electrodynamics(QED)phenomena.However,conventional lase... Ultra-intense electromagnetic fields exceeding 10^(23)W∕cm^(2)are enabling breakthroughs in compact laser-driven particle accelerators and revealing new quantum electrodynamics(QED)phenomena.However,conventional laser-focusing methods face considerable engineering challenges and require substantial costs.Focusing schemes utilizing plasma optics can produce sub-micrometer focus spots beyond the diffraction limit and substantially enhance the peak intensity;however,owing to significant energy dissipation,they may fail to simultaneously increase the laser fluence.To address these challenges,we propose a focusing scheme employing a near-critical-density hollow plasma fiber(HPF)that utilizes graded refractive index dynamics to boost both laser peak intensity and fluence at the same time.Three-dimensional particle-in-cell simulations demonstrate the HPF’s capability to focus a 4.5-μm-diameter Gaussian beam to a sub-diffraction-limited 0.6-μm-diameter spot.The peak intensity and laser fluence can be enhanced by factors of 22 and 10,respectively,marking a substantial improvement over existing plasma-based focusing schemes.Furthermore,the proposed scheme exhibits wide-range parameter adaptation and high robustness,making it suitable for direct implementation in PW-class ultra-intense laser experiments. 展开更多
关键词 plasma optics laser focusing intensity enhancement
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Energy focusing of flexural waves via algorithmically optimized coding metasurface lenses
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作者 Zi-Rui Wang Di-Chao Chen +1 位作者 Rui Hong Da-Jian Wu 《Chinese Physics B》 2025年第9期277-282,共6页
Efficient elastic wave focusing is crucial in materials and physical engineering.Elastic coding metasurfaces,which are innovative planar artificial structures,show great potential for use in the field of wave focusing... Efficient elastic wave focusing is crucial in materials and physical engineering.Elastic coding metasurfaces,which are innovative planar artificial structures,show great potential for use in the field of wave focusing.However,elastic coding lenses(ECLs)still suffer from low focusing performance,thickness comparable to wavelength,and frequency sensitivity.Here,we consider both the structural and material properties of the coding unit,thus realizing further compression of the thickness of the ECL.We chose the simplest ECL,which consists of only two encoding units.The coding unit 0 is a straight structure constructed using a carbon fiber reinforced composite material,and the coding unit 1 is a zigzag structure constructed using an aluminum material,and the thickness of the ECL constructed using them is only 1/8 of the wavelength.Based on the theoretical design,the arrangement of coding units is further optimized using genetic algorithms,which significantly improves the focusing performance of the lens at different focus and frequencies.This study provides a more effective way to control vibration and noise in advanced structures. 展开更多
关键词 coding metasurface elastic wave focusing genetic algorithm
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Multi-dimensional hydrogen bonds regulated emissions of single-molecule system enabling surficial hydrophobicity/hydrophilicity mapping
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作者 Hao Gu Rui Li +6 位作者 Qiuying Li Sheng Lu Yahui Chen Xiaoning Yang Huili Ma Zhijun Xu Xiaoqiang Chen 《Chinese Chemical Letters》 2025年第5期515-520,共6页
Constructing multi-dimensional hydrogen bond(H-bond)regulated single-molecule systems with multiemission remains a challenge.Herein,we report the design of a new excited-state intramolecular proton transfer(ESIPT)feat... Constructing multi-dimensional hydrogen bond(H-bond)regulated single-molecule systems with multiemission remains a challenge.Herein,we report the design of a new excited-state intramolecular proton transfer(ESIPT)featured chromophore(HBT-DPI)that shows flexible emission tunability via the multidimensional regulation of intra-and intermolecular H-bonds.The feature of switchable intramolecular Hbonds is induced via incorporating several hydrogen bond acceptors and donors into one single HBT-DPI molecule,allowing the“turn on/off”of ESIPT process by forming isomers with distinct intramolecular Hbonds configurations.In response to different external H-bonding environments,the obtained four types of crystal/cocrystals vary in the contents of isomers and the molecular packing modes,which are mainly guided by the intermolecular H-bonds,exhibiting non-emissive features or emissions ranging from green to orange.Utilizing the feature of intermolecular H-bond guided molecular packing,we demonstrate the utility of this fluorescent material for visualizing hydrophobic/hydrophilic areas on large-scale heterogeneous surfaces of modified poly(1,1-difluoroethylene)(PVDF)membranes and quantitatively estimating the surface hydrophobicity,providing a new approach for hydrophobicity/hydrophilicity monitoring and measurement.Overall,this study represents a new design strategy for constructing multi-dimensional hydrogen bond regulated ESIPT-based fluorescent materials that enable multiple emissions and unique applications. 展开更多
关键词 multi-dimensional hydrogen bonds Emission regulation Hydrophobicity/hydrophilicity Surficial mapping Excited-state intramolecular proton transfer
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Dynamically Tunable THz Focusing via Mechanically Rotatable Cascaded Metasurfaces With Polarization Multiplexing
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作者 Hui Li Wenhui Xu +5 位作者 Hang Xu Jie Li Chunyu Song Qun Ren Yang Ren Jianquan Yao 《SmartSys》 2025年第3期1-9,共9页
Dynamically tunable terahertz(THz)beam focusing plays a critical role in emerging applications including reconfigurable imaging,localized spectral analysis,and micro-machining.Conventional methods,however,frequently e... Dynamically tunable terahertz(THz)beam focusing plays a critical role in emerging applications including reconfigurable imaging,localized spectral analysis,and micro-machining.Conventional methods,however,frequently employ complex wavefront modulators and external control algorithms,resulting in increased system footprint and limited tuning efficiency.In this work,we present an all-silicon mechanically rotatable cascaded metasurface capable of dynamic THz beam focusing.By independently adjusting the relative rotation angles between the two metasurface layers,real-time repositioning of the focal spot is achieved for orthogonal circular polarization channels.The proposed design facilitates polarization-division multiplexing without requiring external algorithms or active materials while preserving high focusing efficiency and beam quality across a predefined focal plane.Numerical simulations reveal a quasi-linear shift of the focal position with the rotation angle,with stable focusing efficiency and full-width at half-maximum observed in both polarization channels.This strategy offers an efficient and reliable approach to dynamic wavefront control for compact,reconfigurable THz imaging,sensing,and communication systems. 展开更多
关键词 cascaded metasurface dynamic beam focusing polarization-division multiplexing TERAHERTZ wavefront control
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A tunable acoustic metasurface via one-dimensional mechanical adjustment for real-time focusing
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作者 Jie Hu Mengqi Jiang +1 位作者 Rui Zang Yuhang Qian 《Chinese Physics B》 2025年第10期399-404,共6页
Adjustable or programmable metamaterials offer versatile functions,while the complex multi-dimensional regulation increases workload,and hinders their applications in practical scenarios.To address these challenges,we... Adjustable or programmable metamaterials offer versatile functions,while the complex multi-dimensional regulation increases workload,and hinders their applications in practical scenarios.To address these challenges,we present a mechanically programmable acoustic metamaterial for real-time focal tuning via one-dimensional phase-gradient modulation in this paper.The device integrates a phase gradient structure with concave cavity channels and an x-shaped telescopic mechanical framework,enabling dynamic adjustment of inter-unit spacing(1 mm-3 mm)through a microcontroller-driven motor.By modulating the spacing between adjacent channels,the phase gradient is precisely controlled,allowing continuous focal shift from 50 mm to 300 mm along the x-axis at 7500 Hz.Broadband focusing is also discussed in the range6800 Hz-8100 Hz,with transmission coefficients exceeding 0.5,ensuring high efficiency and robust performance.Experimental results align closely with simulations,validating the design's effectiveness and adaptability.Unlike conventional programmable metamaterials requiring multi-dimensional parameter optimization,this approach simplifies real-time control through single-axis mechanical adjustment,significantly reducing operational complexity.Due to the advantages of broadband focusing,simple control mode,real-time monitoring,and so on,the device may have extensive applications in the fields of acoustic imaging,nondestructive testing,ultrasound medical treatment,etc. 展开更多
关键词 phase gradient structure one-dimensional mechanical adjustment adjustable focusing
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Focusing mechanism and anisotropy correction of array induction logging responses for shale reservoirs in horizontal wells
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作者 Lei Wang Kang-Kang Wu +3 位作者 Ying-Ming Liu Xiao-Kai Xu Shao-Gui Deng Ping Qiao 《Petroleum Science》 2025年第12期4992-5004,共13页
We have developed a novel method for correcting resistivity anisotropy in array induction logging(AIL)for shale reservoirs drilled with horizontal wells.This method is featured by two aspects:simplifying software focu... We have developed a novel method for correcting resistivity anisotropy in array induction logging(AIL)for shale reservoirs drilled with horizontal wells.This method is featured by two aspects:simplifying software focusing(SF)algorithm from two-dimensional(2D)to one-dimensional(1D)and approximately decoupling the resistivity anisotropy effect.Initially,the typical raw and focused AIL responses are simulated to determine the applicability of the 2D SF algorithm in deviated and horizontal wells.The non-necessity of SF algorithm along vertical direction is also proved for the pure horizontal wells.Subsequently,a 1D SF algorithm that focuses only along the radial direction in horizontal wells is developed to replace the original 2D SF algorithm.This new method eliminates the opacity of traditional SF algorithms and can be easily applied to different AIL tools.The sensitivity of AIL to resistivity anisotropy in homogeneous and layered formations is then discussed,showing that the anisotropy effect can be separated from other effects.Finally,an efficient anisotropy correction scheme using the Levenberg-Marquardt algorithm is established to quickly and accurately correct AIL data in horizontal wells.Results from simulated and measured data demonstrate that this new method effectively removes the anisotropy effect and provides accurate horizontal resistivity for shale beds drilled with horizontal wells.Compared with existing methods,it is significantly faster and compatible with AIL tools from various companies,laying solid foundation for the interpretation and evaluation of shale reservoirs in horizontal wells. 展开更多
关键词 Shale reservoirs Horizontal wells Array induction logging Software focusing Anisotropy correction
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Plasma-based tunable relativistic laser focusing and strong axial magnetic field generation
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作者 Lingyu Zhang Hao Zhang +2 位作者 Jingyi Wang Xinyan Li Tong-Pu Yu 《High Power Laser Science and Engineering》 2025年第5期104-113,共10页
Precise control of the laser focal position in the relativistic laser–plasma interaction is crucial for electron acceleration,inertial confinement fusion,high-order harmonic generation,etc.However,conventional method... Precise control of the laser focal position in the relativistic laser–plasma interaction is crucial for electron acceleration,inertial confinement fusion,high-order harmonic generation,etc.However,conventional methods are characterized by limited tunability and rapid divergence of the relativistic laser pulse after passing through a single focal point.In this work,we propose a novel plasma lens with a density gradient to achieve laser focusing in a tunable focal volume.The capacity depends on the modification of the phase velocity of the incident seed laser propagating in plasma.By modifying the plasma density gradient,one can even achieve an off-axis focusing plasma lens,allowing the laser to be focused further at an adjustable focus.Based on this new type of optical device,a beam-splitting array is also proposed to leverage this unique focusing mechanism for the generation of strong axial magnetic fields(>1000 T).Three-dimensional particle-in-cell simulations demonstrate that the seed laser with a focal spot of 9μm passing through the density varying plasma lens exhibits a focused laser with a focal spot of approximately 2.3μm and an 18 times enhancement of the laser intensity.The approach has considerable potential for applications in several areas,including laser-driven particle acceleration,X/γ-ray emission,strong magnetic field generation,etc. 展开更多
关键词 axial magnetic field laser—plasma interaction off-axis focusing plasma lens tunable focal volume
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