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Peak current reduction in presence of RF phase modulationin the dual RF system
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作者 Jiang Bocheng Zhang Yao Tsai Cheng-Ying 《强激光与粒子束》 北大核心 2026年第1期160-165,共6页
[Background]High harmonic cavities are widely used in electron storage rings to lengthen thebunch,lower the bunch peak current,thereby reducing the IBS effect,enhancing the Touschek lifetime,as well asproviding Landau... [Background]High harmonic cavities are widely used in electron storage rings to lengthen thebunch,lower the bunch peak current,thereby reducing the IBS effect,enhancing the Touschek lifetime,as well asproviding Landau damping,which is particularly important for storage rings operating with ultra-low emittance or atlow beam energy.[Purpose]To further increase the bunch length without additional hardware costs,the phasemodulation in a dual-RF system is considered.[Methods]In this paper,turn-by-turn simulations incorporating randomsynchrotron radiation excitation are conducted,and a brief analysis is presented to explain the bunch lengtheningmechanism.[Results]Simulation results reveal that the peak current can be further reduced,thereby mitigating IBSeffects and enhancing the Touschek lifetime.Although the energy spread increases,which tends to reduce thebrightness of higher-harmonic radiation from the undulator,the brightness of the fundamental harmonic can,in fact,beimproved. 展开更多
关键词 dual high-frequency system phase modulation beam bunch stretching intra-beam scattering
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Evaluation of Reinforcement Learning-Based Adaptive Modulation in Shallow Sea Acoustic Communication
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作者 Yifan Qiu Xiaoyu Yang +1 位作者 Feng Tong Dongsheng Chen 《哈尔滨工程大学学报(英文版)》 2026年第1期292-299,共8页
While reinforcement learning-based underwater acoustic adaptive modulation shows promise for enabling environment-adaptive communication as supported by extensive simulation-based research,its practical performance re... While reinforcement learning-based underwater acoustic adaptive modulation shows promise for enabling environment-adaptive communication as supported by extensive simulation-based research,its practical performance remains underexplored in field investigations.To evaluate the practical applicability of this emerging technique in adverse shallow sea channels,a field experiment was conducted using three communication modes:orthogonal frequency division multiplexing(OFDM),M-ary frequency-shift keying(MFSK),and direct sequence spread spectrum(DSSS)for reinforcement learning-driven adaptive modulation.Specifically,a Q-learning method is used to select the optimal modulation mode according to the channel quality quantified by signal-to-noise ratio,multipath spread length,and Doppler frequency offset.Experimental results demonstrate that the reinforcement learning-based adaptive modulation scheme outperformed fixed threshold detection in terms of total throughput and average bit error rate,surpassing conventional adaptive modulation strategies. 展开更多
关键词 Adaptive modulation Shallow sea underwater acoustic modulation Reinforcement learning
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Unlocking Wavelength-Selective Modulations of Open-Circuit Voltage in Metal Halide Perovskite Solar Cells
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作者 Younsuk Hu Jibeom Hong +3 位作者 Kyounguk Cho Wanseung Yoo Doo Hyun Ko Inchan Hwang 《Energy & Environmental Materials》 2026年第1期329-340,共12页
The photovoltaic performance of metal halide perovskite solar cells often respond divergently to environmental conditions during storage.In particular,light exposure can either enhance or degrade device efficiency,yet... The photovoltaic performance of metal halide perovskite solar cells often respond divergently to environmental conditions during storage.In particular,light exposure can either enhance or degrade device efficiency,yet the mechanisms underlying these antithetical behaviors are still under investigation.In this study,we explore the modulation of the open-circuit voltage(Voc)in triple-cation mixed-halide perovskite solar cells by systematically controlling storage environments.While light intensity exhibits minimal impact during storage,the spectral composition of illumination selectively enhances Voc comprising reversible and irreversible contributions.Structural characterization reveals that prolonged storage degrades the quality of perovskite crystals in the upper region of the perovskite layer,whereas light storage promotes the relaxation of microstrain at the buried interface with a p-type organic layer.This structural reorganization at the interface,accompanied by lattice expansion,accounts for suppressed nonradiative recombination and a corresponding increase in quasi-Fermi level splitting.Consequently,devices fabricated without chemical defect passivation achieve a power conversion efficiency of higher than 40%under indoor lighting conditions after preconditioned by continuous exposure to ambient light during storage.These findings highlight the critical role of controlled light exposure during storage not only in enhancing efficiency,but also in ensuring reproducibility of perovskite solar cell characterization. 展开更多
关键词 indoor photovoltaics light-induced modulations perovskite solar cells REPRODUCIBILITY strain relaxation
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Lattice-oxygen modulation for redox stabilization and multi-electron transfer in lithium-rich cathodes
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作者 Mingche Huang Ruian Fan +5 位作者 Chenkai Sun Aoshen Duan Hao Cheng Ruguang Ma Erhong Song Jianjun Liu 《Materials Reports(Energy)》 2026年第1期94-102,共9页
Lithium-rich layered oxides(LRLOs)are promising cathode materials due to their high specific capacity,energy density,and operating voltage.However,their performance is hindered by the limited redox activity of transit... Lithium-rich layered oxides(LRLOs)are promising cathode materials due to their high specific capacity,energy density,and operating voltage.However,their performance is hindered by the limited redox activity of transition metals,leading to oxygen redox instability,oxygen release,and capacity degradation.To address these issues,we propose an innovative lattice-oxygen modulation(LOM)strategy that incorporates Mn^(3+)and Ti^(4+)into the Li_(1.2)Cr_(0.3)Mn_(0.4)Ti_(0.1)O_(2) system,effectively mitigating Cr migration,stabilizing oxygen redox reactions,and reinforcing structural integrity.This results in improved electrochemical performance,as demonstrated by a 56.5 mAh g^(−1) increase in initial discharge capacity to 364.2 mAh g^(−1),with 71.3%capacity retention after 30 cycles,reflecting a 20.2%improvement in cycling stability.Density functional theory(DFT)calculations confirm enhanced Cr redox reversibility and reduced oxygen evolution,further strengthening structural stability.These synergistic effects highlight the pivotal role of the LOM strategy in optimizing both electrochemical performance and structural integrity,offering a scalable pathway to improve capacity and cycling stability in lithium-rich cathodes. 展开更多
关键词 Lithium-rich cathodes Oxygen modulation Redox stabilization Multi-electron transfer enhancement Lattice reinforcement
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Tea polyphenol polymer film enables broadband optical modulation for hybrid mode-locked ultrafast fiber lasers
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作者 Wei Chen Kang Li +4 位作者 Cheng Gao Qingping Hu Zhengfan Li Yi Xiong Yunzhou Sun 《Chinese Physics B》 2026年第2期442-450,共9页
Materials exhibiting broadband nonlinear optical responses are critically important for ultrafast photonics applications,particularly as saturable absorbers(SAs)that facilitate broadband optical pulse generation.In th... Materials exhibiting broadband nonlinear optical responses are critically important for ultrafast photonics applications,particularly as saturable absorbers(SAs)that facilitate broadband optical pulse generation.In this study,tea polyphenolpolyvinyl alcohol(TP-PVA)composite films are synthesized via a polymer embedding method and employed as SAs to initiate ultrafast pulse operation in fiber lasers.The TP-PVA SA film exhibits excellent broadband saturable absorption performance at wavelengths of 1.0μm,1.5μm,and 2.0μm,with modulation depths of 54.21%,41.41%,and 51.16%,respectively.Stable passively mode-locked pulses with pulse widths of 588 fs,419 fs,and 743 fs are generated in Yb-,Er-,and Tm-doped fiber lasers,respectively.This work confirms the effective performance of TP-PVA as a broadband SA,and establishes a foundation for the integration of novel and sustainable materials within ultrafast photonic systems.The approach paves the way for developing compact broadband ultrafast laser systems operating in the near-infrared spectral region. 展开更多
关键词 ultrafast fiber lasers saturable absorbers broadband modulators natural dyes tea polyphenol
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Double-side delay alignment modulation for multi-user millimeter wave and terahertz communications
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作者 Xingwei Wang Haiquan Lu +1 位作者 Jieni Zhang Yong Zeng 《Digital Communications and Networks》 2026年第1期11-24,共14页
Delay Alignment Modulation(DAM)is an innovative broadband modulation technique well-suited for millimeter Wave(mm Wave)and Terahertz(THz)massive Multiple-Input Multiple-Output(MIMO)communication systems.Leveraging the... Delay Alignment Modulation(DAM)is an innovative broadband modulation technique well-suited for millimeter Wave(mm Wave)and Terahertz(THz)massive Multiple-Input Multiple-Output(MIMO)communication systems.Leveraging the high spatial resolution and sparsity of multi-path channels,DAM effectively mitigates Inter-Symbol Interference(ISI)by aligning all multi-path components through a combination of delay pre-compensation(or post-compensation)and path-based beamforming.As such,ISI is eliminated while preserving multi-path power gains.In this paper,we investigate multi-user double-side DAM,which incorporates both delay pre-compensation at the transmitter and post-compensation at the receiver,in contrast to prior works that primarily focus on singleside DAM with only delay pre-compensation.Firstly,we derive the constraint on the number of introduced delays and formulate the corresponding delay pre/post-compensation vectors tailored for multi-user double-side DAM,given a specific number of delay compensations.Furthermore,we demonstrate that when the number of Base Stations(BSs)/User Equipment(UE)antennas is sufficiently large,single-side DAM—where delay compensation is performed only at the BS/UE—is preferable to double-side DAM,since the former results in less ISI to be spatially eliminated.Next,we propose two low-complexity path-based beamforming strategies based on the eigen-beamforming transmission and ISI-Zero Forcing(ZF),respectively.On this basis,we further analyze the achievable sum rates.Simulation results verify that with a sufficiently large number of BS/UE antennas,singleside DAM is adequate for ISI elimination.Moreover,compared to the benchmarking scheme of Orthogonal Frequency Division Multiplexing(OFDM),multi-user BS-side DAM achieves higher spectral efficiency and lower Peak-to-Average Power Ratio(PAPR). 展开更多
关键词 Delay alignment modulation Delay pre-compensation Delay post-compensation Path-based beamforming Fractional channel delay
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Dual-region synergistic modulation and (101) facet engineering for highly reversible zinc anodes
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作者 Shuai Zhang Kittima Lolupiman +5 位作者 Dongdong Zhang Zixuan Gao Rungroj Chanajaree Xinyu Zhang Jin Cao Jiaqian Qin 《Advanced Powder Materials》 2026年第1期99-111,共13页
Aqueous zinc-ion batteries(AZIBs)offer promising safety and affordability,but suffer from dendritic Zn growth and parasitic side reactions at the electrode-electrolyte interface.Herein,we construct a dual-region inter... Aqueous zinc-ion batteries(AZIBs)offer promising safety and affordability,but suffer from dendritic Zn growth and parasitic side reactions at the electrode-electrolyte interface.Herein,we construct a dual-region interfacial modulation framework by molecularly reconfiguring the Helmholtz double layer via trace methyl methacrylate(MMA).Exploiting its amphiphilic and functionally asymmetric architecture,MMA enables a coordinated interfacial reconstruction that disrupts Zn^(2+)solvation in the outer Helmholtz plane,builds a chemisorbed coordination layer in the inner plane,and modulates local interfacial chemistry with spatial precision.This dualregion regulation collectively suppresses water reactivity,facilitates Zn^(2+)desolvation,and drives crystallo-graphically preferred deposition along the(101)plane,promoting lateral growth and mitigating dendrite for-mation.As a result,symmetric Zn||Zn cells exhibit over 4200 h of stable cycling at 1 mA cm^(-2) and maintain 1100 h of operation at 2 mA cm^(-2),even at 0℃.Zn||Ti half-cells achieve a Coulombic efficiency of 99.83%,while Zn||NH_(4)V_(4)O_(10) full cells deliver 93.92%capacity retention after 400 cycles at 2 A g^(-1),and preserve 85.3%after 300 cycles at 0℃.This work demonstrates a scalable,mechanism-driven electrolyte design paradigm for dendrite-free and high-performance aqueous Zn metal batteries. 展开更多
关键词 Aqueous zinc-ion batteries Helmholtz plane engineering Dendrite suppression Solvation modulation Facet-selective Zn deposition
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Periodontitis-associated salivary microbiota exacerbates systemic osteoclastogenesis via gut modulation and tryptophan metabolism suppression in ovariectomized mice
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作者 Nannan Wang Jun Qian +7 位作者 Min Wang Lili Li Wenzheng Liao Rixin Chen Hua Nie Ruiyang Ge Fangfang Sun Fuhua Yan 《International Journal of Oral Science》 2026年第1期152-164,共13页
Epidemiological studies have highlighted an association between periodontitis and osteoporosis.However,the mechanism underlining this association remains unclear.Here,we revealed significant differences in the salivar... Epidemiological studies have highlighted an association between periodontitis and osteoporosis.However,the mechanism underlining this association remains unclear.Here,we revealed significant differences in the salivary microbiota between periodontally healthy individuals and periodontitis patients,with periodontitis patients exhibiting increased salivary microbiota diversity and an elevated abundance of pathogenic bacteria.Using an ovariectomized(OVX) mouse model,we demonstrated that the salivary microbiota from periodontitis patients exacerbated bone destruction by modulating the gut microbiota.Metabolomic analysis revealed that the periodontitis-associated salivary microbiota suppressed tryptophan metabolism.The tryptophan metabolite indole-3-lactic acid(ILA) directly inhibited osteoclast formation and differentiation.In OVX mice treated with periodontitis salivary microbiota,supplementation with ILA effectively suppressed osteoclastogenesis and alleviated the detrimental effects of periodontitis-associated salivary microbiota on systemic bones.In summary,our data demonstrate that periodontitis can affect systemic bone metabolism via the oral-gut axis and that ILA supplementation serves as a potential therapeutic option to mitigate these adverse effects. 展开更多
关键词 tryptophan metabolism salivary microbiota PERIODONTITIS OSTEOCLASTOGENESIS pathogenic bacteriausing epidemiological studies indole lactic acid gut modulation
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Complexity-Reduced Equalization for 200 Gbit/s PON Downstream Systems Based on SSB Modulation and Direct Detection
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作者 Yang Tao Huang Xingang +3 位作者 Ma Zhuang Zhong Yiming Huang Xiatao Liu Bo 《ZTE Communications》 2026年第1期56-64,共9页
The 200 Gbit/s passive optical network(PON)is most likely to be the next-generation scheme following 50G PON.The costeffective direct detection(DD)system is the economical choice.However,larger-capacity DD systems wil... The 200 Gbit/s passive optical network(PON)is most likely to be the next-generation scheme following 50G PON.The costeffective direct detection(DD)system is the economical choice.However,larger-capacity DD systems will face much more serious power fading caused by chromatic dispersion(CD)combined with square-law DD and thereby significantly increases the complexity of equalization algorithms.In this paper,a 200 Gbit/s Nyquist 4-level pulse amplitude modulation(PAM4)single side-band(SSB)modulation-DD downlink scheme is designed,and a low complexity quadratic-nonlinear equalizer is proposed for this system.The computational complexity of the quadratic nonlinear equalizer is about 28%of that of the conventional Volterra nonlinear equalizer,while still exhibiting excellent nonlinear equalization ability.Simulation results for the 200 Gbit/s system with 20 km fiber transmission show that it can achieve a power budget of 29 dB,while a 30.4 dB power budget is obtained in the 50 Gbit/s experimental transmission. 展开更多
关键词 200 Gbit/s passive optical network single side band modulation direct detection EQUALIZATION
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Modulation of mitochondrial dysfunction:Mechanisms and strategies for the use of natural products to treat stroke
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作者 Na Qin Rujuan Liu +3 位作者 Rong Deng Liuliu Shi Lei Wang Ting Zhu 《Neural Regeneration Research》 2026年第6期2215-2226,共12页
Modulations of mitochondrial dysfunction,which involve a series of dynamic processes such as mitochondrial biogenesis,mitochondrial fusion and fission,mitochondrial transport,mitochondrial autophagy,mitochondrial apop... Modulations of mitochondrial dysfunction,which involve a series of dynamic processes such as mitochondrial biogenesis,mitochondrial fusion and fission,mitochondrial transport,mitochondrial autophagy,mitochondrial apoptosis,and oxidative stress,play an important role in the onset and progression of stroke.With a better understanding of the critical role of mitochondrial dysfunction modulations in post-stroke neurological injury,these modulations have emerged as a potential target for stroke prevention and treatment.Additionally,since effective treatments for stroke are extremely limited and natural products currently offer some outstanding advantages,we focused on the findings and mechanisms of action related to the use of natural products for targeting mitochondrial dysfunction in the treatment of stroke.Natural products achieve neuroprotective through multi-target regulation of mitochondrial dysfunction encompassing the following processes:(1)Mitochondrial biogenesis:Cordyceps and hydroxysafflor yellow A activate the peroxisome proliferator-activated receptor gamma coactivator 1-alpha/nuclear respiratory factor pathway,promote mitochondrial DNA replication and respiratory chain protein synthesis,and thereby restore energy supply in the ischemic penumbra.(2)Mitochondrial dynamics balance:Ginsenoside Rb3 promotes Opa1-mediated neural stem cell migration and diffusion for recovery of damaged brain tissue.(3)Mitochondrial autophagy:Gypenoside XVII selectively eliminates damaged mitochondria via the phosphatase and tensin homolog-induced kinase 1/Parkin pathway and blocks reactive oxygen species and the NOD-like receptor protein 3 inflammasome cascade,thereby alleviating blood-brain barrier damage.(4)Anti-apoptotic mechanisms:Ginkgolide K inhibits Bax mitochondrial translocation and downregulates caspase-3/9 activity,reducing neuronal programmed death induced by ischemia-reperfusion.(5)Oxidative stress regulation:Scutellarin exerts antioxidant properties and improves neurological function by modulating the extracellular signal-regulated kinase 5-Kruppel-like factor 2-endothelial nitric oxide synthase signaling pathway.(6)Intercellular mitochondrial transport:Neuroprotective effects of Chrysophanol are associated with accelerated mitochondrial transfer from astrocytes to neurons.Existing studies have confirmed that natural products exhibit neuroprotective effects through multidimensional interventions targeting mitochondrial dysfunction in both ischemic and hemorrhagic stroke models.However,their clinical translation still faces challenges,such as the difficulty in standardization due to component complexity,insufficient cross-regional clinical data,and the lack of long-term safety evaluations.Future research should aim to integrate new technologies,such as single-cell sequencing and organoid models,to deeply explore the mitochondria-targeting mechanisms of natural products and validate their efficacy through multicenter clinical trials,providing theoretical support and translational pathways for the development of novel anti-stroke drugs. 展开更多
关键词 apoptosis AUTOPHAGY hemorrhagic stroke ischemic stroke mitochondrial biogenesis mitochondrial dynamics mitochondrial dysfunction modulations mitochondrial transport natural products oxidative stress
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Artificial Cooper-Pair Density Modulation in Buckled Heterostructure
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作者 Zhongrui Wang Yingbo Wang +10 位作者 Xiangjia Bai Lu Cao Yucheng Xue Yang Cao Dawei Zhai Hong-Jun Gao Francois M.Peeters Bert Jorissen Lucian Covaci Yuhang Jiang Jinhai Mao 《Chinese Physics Letters》 2026年第3期147-176,共30页
erized by a periodic real-space modulation of the superconducting pairing order parameter,is a novel quantum phase observed in superconducting(SC)systems.It is believed to play a key role in understanding the pseudoga... erized by a periodic real-space modulation of the superconducting pairing order parameter,is a novel quantum phase observed in superconducting(SC)systems.It is believed to play a key role in understanding the pseudogap phase of superconductors and has recently been discovered in bulk cuprates,transition-metal dichalcogenide,and other unconventional superconductors.However,artificially engineered PDW in designable two-dimensional materials remain rare.In this paper,we report a strain-assisted strategy to realize cooper-pair density modulation in a van der Waals heterostructure:graphene on SC 2H-NbSe2.Superconductivity is induced in graphene via the proximity effect.Meanwhile,the graphene membrane spontaneously buckles into a periodic structure owing to strain,featuring a spatially modulated local density of states(LDOS).The interplay between the spatially modulated LDOS and the proximity-induced superconductivity results in an oscillatory pair density determined by the buckled geometry,constituting an artificial PDW.This approach enables the engineering of PDWs with periodicities of up to tens of nanometers and allows their realization in a variety of heterostructures with tailored designs.Our work provides new insights into the investigation of PDW physics using predesigned two-dimensional materials. 展开更多
关键词 strain assisted strategy graphene proximity effect quantum phase artificial Cooper pair density modulation van der waals heterostructure pseudogap phase bulk cupratestransition metal
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Magnetic-Field Modulation of Na_(3)V_(2)(PO_(4))_(3)Crystal Orientation for Enhanced Sodium-Ion Battery Performance
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作者 Pengcheng Wang Xuqi Lin +6 位作者 Houlin Cheng Ciqi Yuan Yongping Zheng Yingbin Lin Zhigao Huang Hao Chen Jiaxin Li 《Carbon Energy》 2026年第2期221-235,共15页
Na_(3)V_(2)(PO_(4))_(3)(NVP)is a promising electrode material that exhibits magnetic anisotropy;however,the potential of this magnetic anisotropy to optimize battery performance has been largely unexplored.This study ... Na_(3)V_(2)(PO_(4))_(3)(NVP)is a promising electrode material that exhibits magnetic anisotropy;however,the potential of this magnetic anisotropy to optimize battery performance has been largely unexplored.This study proposes a cost-effective and efficient method to induce the alignment of NVP along the(113)crystal plane by applying a vertical magnetic field during the slurry coating process,thereby enhancing its battery performance.Comprehensive structural characterizations and theoretical analysis elucidate the structure-activity relationship between the preferred crystal orientation and ion transport kinetics,facilitating the formation of more ordered Na+deintercalation pathways in NVP electrodes.This alignment reduces electrode tortuosity,enhances interfacial compatibility,and substantially improves battery performance,particularly in terms of high-rate cycling capability.As a result,the magnetic-field-modulated NVP(NVP-M⊥)electrode exhibits a high capacity retention of85.1%after 500 cycles at 5 C,significantly surpassing that of the pristine electrode.The NVP-M⊥electrode also demonstrates considerable reversible capacity at 40 C and maintains excellent stability under high temperature and prolonged cycling conditions.Furthermore,superior battery performance is observed in the assembled NVP-M⊥‖hard-carbon pouch cell and commercial NVP electrode following magnetic-field modulation,thereby validating the efficacy of this method.Consequently,this magnetic-field-induced crystal-orientation optimization strategy provides an innovative approach for low-cost and highthroughput preparation of high-performance sodium-ion batteries. 展开更多
关键词 battery performance magnetic‐field modulation Na_(3)V_(2)(PO_(4))_(3)cathode sodium‐ion batteries thermalsafety
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基于斩波电路的全速域NSPWM策略研究
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作者 陈磊 乔辉 +5 位作者 孙正东 张保刚 李豪 刘文 苗轶如 杨涛 《成都工业学院学报》 2026年第1期31-37,共7页
在三相电压源型电机驱动系统中,共模电压所产生的轴电流会腐蚀电机的轴承,增加电机的振动噪声,还会产生强烈的电磁干扰,严重影响了整个系统的可靠性。为此,提出基于斩波电路的全速域邻近矢量脉宽调制(NSPWM)策略。在对共模电压产生机理... 在三相电压源型电机驱动系统中,共模电压所产生的轴电流会腐蚀电机的轴承,增加电机的振动噪声,还会产生强烈的电磁干扰,严重影响了整个系统的可靠性。为此,提出基于斩波电路的全速域邻近矢量脉宽调制(NSPWM)策略。在对共模电压产生机理进行分析的基础上,确定采用NSPWM策略,可通过消除零矢量减小共模电压,同时具有较低的开关损耗与电流纹波,并推导了NSPWM各矢量作用时间的计算方法。针对低调制比区域NSPWM无法适用的问题,在三相电压源型的前级增加了斩波电路,设计了直流母线电压的控制方法,以通过降低直流母线电压扩大NSPWM的应用区域。最后进行了仿真验证,并与动态零矢量脉宽调制策略进行了比较。结果表明,在消除零矢量的前提下,所提NSPWM在低调制比区域具有更加优越的稳态性能。电流总谐波畸变率由5.42%降低至3.72%,转矩脉动由±0.3 N·m降低至±0.2 N·m。 展开更多
关键词 共模电压 电压源型逆变器 邻近矢量脉宽调制 斩波电路
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基于蜣螂算法优化PI双闭环SPWM逆变器的设计
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作者 李国洪 王光瑞 《现代电子技术》 北大核心 2025年第14期33-37,共5页
为了提高PI控制器的控制精度,提出一种基于蜣螂优化(DBO)算法的PI双闭环SPWM逆变器控制方法。通过模拟蜣螂的自然觅食行为,DBO算法能够有效地在参数空间进行全局探索和局部细化,其自适应的搜索策略和快速收敛特性使其在寻找最优PI控制... 为了提高PI控制器的控制精度,提出一种基于蜣螂优化(DBO)算法的PI双闭环SPWM逆变器控制方法。通过模拟蜣螂的自然觅食行为,DBO算法能够有效地在参数空间进行全局探索和局部细化,其自适应的搜索策略和快速收敛特性使其在寻找最优PI控制器参数时表现出高效性和准确性。通过在Matlab/Simulink中建立仿真模型并与PSO和MFO两个优化算法比较,结果表明,利用DBO优化的PI参数在双闭环逆变器的控制系统中具有更低的THD值和更好的稳定性能。 展开更多
关键词 DBO PI控制 spwm 双闭环控制 逆变器 单位阶跃响应
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基于SPWM的双闭环控制下低压电流互感器全量程升流技术研究 被引量:1
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作者 尹文庆 王永超 李宁 《电测与仪表》 北大核心 2025年第10期106-114,共9页
文章聚焦于优化电流注入控制系统在低压型电流互感器带电测量中的应用,旨在动态工况下实现工频电流的精确自主调制。文中构建了基于正弦脉宽调制(sinusoidal pulse width modulation,SPWM)技术的带电回路调控系统,通过逆变电路生成交流... 文章聚焦于优化电流注入控制系统在低压型电流互感器带电测量中的应用,旨在动态工况下实现工频电流的精确自主调制。文中构建了基于正弦脉宽调制(sinusoidal pulse width modulation,SPWM)技术的带电回路调控系统,通过逆变电路生成交流信号,并与互感器协同工作,快速准确地向被测电路注入电流。针对延迟问题,分析了滤波电路和执行器响应的影响,并采用双闭环控制策略,有效减轻滤波压力并降低滞后延迟。利用根轨迹法验证了系统稳定性,并通过频域分析法优化比例积分(proportional-integral,PI)控制参数。Simulink仿真结果显示,注入电流控制系统实现了工频电流在1%~120%额定电流范围内自主调制。最终,实现了在带电条件下对测试回路电流的全量程调控,为电力系统的高精度电流测量提供了可靠解决方案。 展开更多
关键词 电流调控 spwm技术 双闭环控制系统
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基于Simulink的SPWM三相逆变器仿真分析 被引量:1
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作者 张凯 周云艳 +1 位作者 瞿超然 张懂 《现代信息科技》 2025年第17期28-31,37,共5页
三相逆变器将直流电转换为交流电,为牵引电机提供稳定电源。采用SPWM(Sinusoidal Pulse Width Modulation)控制技术,通过调制正弦波与三角波生成脉冲信号,优化输出波形。搭建了包含IGBT模块、直流电源、三相负载及LC滤波电路的仿真模型... 三相逆变器将直流电转换为交流电,为牵引电机提供稳定电源。采用SPWM(Sinusoidal Pulse Width Modulation)控制技术,通过调制正弦波与三角波生成脉冲信号,优化输出波形。搭建了包含IGBT模块、直流电源、三相负载及LC滤波电路的仿真模型,分析了不同条件下的输出电压波形、谐波特性及转换效率。结果表明,LC滤波电路显著改善了输出波形质量,降低了谐波失真(从79.4%降至1.16%),并实现了较高的转换效率。研究为车辆牵引供电系统的稳定运行提供了理论支持,未来需进一步优化设计以适应复杂工况。 展开更多
关键词 spwm 逆变器 谐波失真 转换效率
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基于单相SPWM变频调速系统的故障检测装置设计与调试
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作者 陈柬 陈棋 《科技创新与应用》 2025年第12期119-122,共4页
该文详细介绍一种基于SPWM变频调速系统的故障检测装置的结构、工作原理、设计与调试方法。该研究对提高SPWM变频调速系统分析、波形观察、故障分析和故障解决能力有较好的指导和借鉴作用。
关键词 spwm变频调速 故障检测 透明面板 装置设计 调试
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A Dual Arm Complementary Hybrid Modulation Strategy Combining NL-SPWM for MMC Applications
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作者 Mingwan Mei Ping Wang +3 位作者 Yanbo Che Zihan Lv Zmarrak Wali Khanand Chao Xing 《Energy Engineering》 EI 2022年第2期591-607,共17页
In the medium voltage direct current(MVDC)transmission system,a small number of MMC sub modules will reduce the power quality.In this paper,based on the research background of Photovoltaic Medium VoltageDirect Current... In the medium voltage direct current(MVDC)transmission system,a small number of MMC sub modules will reduce the power quality.In this paper,based on the research background of Photovoltaic Medium VoltageDirect Current(PV-MVDC)system,aHybrid Modulation Strategy based on theDecoupledDouble SynchronousReference Frame(DDSRF)control strategy is proposed.The dual armcomplementary hybrid modulation combining nearest-level-SPWM(NL-SPWM)can keep the number of SMs in the ON state constant.Then,the corresponding voltage sharing control algorithm of sub module(SM)is introduced.Through theoretical calculation,the modulation strategy can be found to stabilize the DC voltage and reduce the harmonic content.A32-level MMC systemhas been developed to verity that the proposed hybrid modulation strategy and its SM voltage sharing algorithm have the advantages of restraining circulating current and maintaining capacitor voltage balance. 展开更多
关键词 Modular multilevel converter modulation strategy dual arm complementary nearest-level-modulation harmonics improvement
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Spin-dependent amplitude and phase modulation with multifold interferences via single-layer diatomic all-silicon metasurfaces 被引量:3
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作者 Hui Li Chenhui Zhao +6 位作者 Jie Li Hang Xu Wenhui Xu Qi Tan Chunyu Song Yun Shen Jianquan Yao 《Opto-Electronic Science》 2025年第3期2-15,共14页
Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarizat... Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarization.Geometric phase profiles with spin-selective properties are commonly associated with wavefront modulation,allowing the implementation of conjugate strategies within orthogonal circularly polarized channels.Simultaneous control of these characteristics in a single-layered diatomic metasurface will be an apparent technological extension.Here,spin-selective modulation of terahertz(THz)beams is realized by assembling a pair of meta-atoms with birefringent effects.The distinct modulation functions arise from geometric phase profiles characterized by multiple rotational properties,which introduce independent parametric factors that elucidate their physical significance.By arranging the key parameters,the proposed design strategy can be employed to realize independent amplitude and phase manipulation.A series of THz metasurface samples with specific modulation functions are characterized,experimentally demonstrating the accuracy of on-demand manipulation.This research paves the way for all-silicon meta-optics that may have great potential in imaging,sensing and detection. 展开更多
关键词 diatomic metasurface geometric phase complex amplitude modulation spin-selective
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Multi-frequency formation mechanism and modulation strategy of self-priming enhanced submerged pulsed waterjet 被引量:1
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作者 Haojie Jia Yanwei Liu +6 位作者 Weiqin Zuo Hongkai Han Ping Chang Mohammad Waqar Ali Asad Guozhong Hu Jian Miao Hani SMitri 《International Journal of Mining Science and Technology》 2025年第2期175-189,共15页
Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure throug... Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure through self-priming. However, their pressure frequency and cavitation characteristics remain unclear, resulting in an inability to fully utilize resonance and cavitation erosion to break coal and rock. In this study, high-frequency pressure testing, high-speed photography, and large eddy simulation(LES) are used to investigate the distribution of the pressure frequency band, evolution law of the cavitation cloud, and its regulation mechanism of a continuous waterjet, SOPW, and AFESOPW. The results indicated that the excitation of the plunger pump, shearing layer vortex, and bubble collapse corresponded to the three high-amplitude frequency bands of the waterjet pressure. AFESOPWs have an additional self-priming frequency that can produce a larger amplitude under a synergistic effect with the second high-amplitude frequency band. A better cavitation effect was produced after self-priming the annulus fluid, and the shedding frequency of the cavitation clouds of the three types of waterjets was linearly related to the cavitation number. The peak pressure of the waterjet and cavitation erosion effect can be improved by modulating the waterjet pressure oscillation frequency and cavitation shedding frequency. 展开更多
关键词 MULTI-FREQUENCY modulation SELF-PRIMING Submerged waterjet CAVITATION
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