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Weak Co-AB-context for G_(C)-χ-injective Modules
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作者 YANG Qiang 《数学进展》 北大核心 2026年第1期103-119,共17页
In this paper,we introduce the notion of G_(C)-X-injective modules,where X denotes a class of left S-modules and C represents a faithfully semidualizing bimodule.Under the condition that X satisfies certain hypotheses... In this paper,we introduce the notion of G_(C)-X-injective modules,where X denotes a class of left S-modules and C represents a faithfully semidualizing bimodule.Under the condition that X satisfies certain hypotheses,some properties and some equivalent characterizations of G_(C)-X-injective modules are investigated,and we also show that the triple(■,cores■,■)is a weak co-AB-context.As an application,two complete cotorsion pairs and a new model structure in Mod S are given. 展开更多
关键词 C-X-injective module G_(C)-X-injective module cotorsion pair weak co-ABcontext
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Impact of Well Thickness on Static and Dynamic Behavior of InGaN Light-emitting Diode with Single Quantum Well
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作者 CHEN Guichu HE Longfei PENG Kun 《发光学报》 北大核心 2026年第2期314-320,共7页
In this paper,we present a circuit model of single-quantum-well InGaN/GaN light-emitting diodes based on the standard rate equations.Two rate equations describe carrier transport processes occurring in sep-arate confi... In this paper,we present a circuit model of single-quantum-well InGaN/GaN light-emitting diodes based on the standard rate equations.Two rate equations describe carrier transport processes occurring in sep-arate confinement heterostructure and quantum well respectively,and the third equation describes the varied photons in quantum well.By using the presented model,impacts of quantum well thickness on the static and dynamic performances are investigated.Simulated results show that LED with 4 nm well exhibits better lightcurrent(L-I)performance,but LED with 3 nm well presents wider 3 dB modulation bandwidth.It reveals that high carrier density in quantum well is detrimental to the static performance,but beneficial to the dynamic performance. 展开更多
关键词 single quantum well rate equations circuit model L-I performance modulation bandwidth
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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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Biomimetic Nanotechnology Integrating TargetedDelivery and Immune Regulation in Stroke Therapy
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作者 LIU Yang 《生物化学与生物物理进展》 北大核心 2026年第3期515-515,共1页
Ischemic stroke therapy has long been dominated by strategies aimed at restoring cerebral blood flow. Yet, accumulating evidence suggests that neuronal survival and functional recovery depend not only on reperfusion, ... Ischemic stroke therapy has long been dominated by strategies aimed at restoring cerebral blood flow. Yet, accumulating evidence suggests that neuronal survival and functional recovery depend not only on reperfusion, but also on the resolution of postischemic immune dysregulation. This study(Chen et al., Prog Biochem Biophys, 2026, 53(3): 697-710. DOI:10.3724/j.pibb.2025.0541) a dvances this emerging paradigm by proposing a therapeutic strategy that integrates lesion-specific delivery with active modulation of the inflammatory microenvironment. 展开更多
关键词 neuronal survival active modulation o immune regulation ischemic stroke therapeutic strategy ischemic stroke therapy biomimetic nanotechnology restoring cerebral blood flow
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Enhancing Lightweight Mango Disease Detection Model Performance through a Combined Attention Module
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作者 Wen-Tsai Sung Indra Griha TofikIsa Sung-Jung Hsiao 《Computers, Materials & Continua》 2026年第2期986-1016,共31页
Mango is a plant with high economic value in the agricultural industry;thus,it is necessary to maximize the productivity performance of the mango plant,which can be done by implementing artificial intelligence.In this... Mango is a plant with high economic value in the agricultural industry;thus,it is necessary to maximize the productivity performance of the mango plant,which can be done by implementing artificial intelligence.In this study,a lightweight object detection model will be developed that can detect mango plant conditions based on disease potential,so that it becomes an early detection warning system that has an impact on increasing agricultural productivity.The proposed lightweight model integrates YOLOv7-Tiny and the proposed modules,namely the C2S module.The C2S module consists of three sub-modules such as the convolutional block attention module(CBAM),the coordinate attention(CA)module,and the squeeze-and-excitation(SE)module.The dataset is constructed by eight classes,including seven classes of disease conditions and one class of health conditions.The experimental result shows that the proposed lightweight model has the optimal results,which increase by 13.15% of mAP50 compared to the original model YOLOv7-Tiny.While the mAP50:95 also achieved the highest results compared to other models,including YOLOv3-Tiny,YOLOv4-Tiny,YOLOv5,and YOLOv7-Tiny.The advantage of the proposed lightweightmodel is the adaptability that supports it in constrained environments,such as edge computing systems.This proposedmodel can support a robust,precise,and convenient precision agriculture system for the user. 展开更多
关键词 Mango lightweight model combined attention module C2S module precision agriculture
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Suppression of ablative Rayleigh–Taylor instability by spatially modulated laser in inertial confinement fusion
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作者 Zhantao Lu Xinglong Xie +10 位作者 Xiao Liang Meizhi Sun Ping Zhu Xuejie Zhang Chunqing Xing Linjun Li Hao Xue Guoli Zhang Rashid Ul Haq Dongjun Zhang Jianqiang Zhu 《Matter and Radiation at Extremes》 2026年第1期29-38,共10页
The suppression of ablative Rayleigh–Taylor instability(ARTI)by a spatially modulated laser in inertial confinement fusion(ICF)is studied through numerical simulations.The results show that in the acceleration phase ... The suppression of ablative Rayleigh–Taylor instability(ARTI)by a spatially modulated laser in inertial confinement fusion(ICF)is studied through numerical simulations.The results show that in the acceleration phase of ICF implosion,the growth of ARTI can be suppressed by using a short-wavelength spatially modulated laser.The ARTI growth rate decreases as the wavelength of the spatially modulated laser decreases,and ARTI is completely suppressed after a certain wavelength has been reached.A spatially uniform laser is introduced to keep the state of motion of the implosion fluid consistent,and it is found that the proportion of the spatially modulated laser required for complete suppression of ARTI decreases as the wavelength continues to decrease.We also optimize the spatial intensity distribution of the spatially modulated laser.In addition,as the duration of the spatially modulated laser decreases,the proportion required for completely suppressing ARTI increases,but the required energy decreases.When the perturbation wavenumber decreases,the wavelength of the spatially modulated laser required for complete suppression of ARTI becomes longer.In the case of multimode perturbation,ARTI can also be significantly suppressed by a spatially modulated laser,and the perturbation amplitude can be reduced to less than 10% of that without a spatially modulated laser.We believe that the conclusions drawn from our simulations can provide the basis for new approaches to control ARTI in ICF. 展开更多
关键词 ablative Rayleigh Taylor instability ablative rayleigh taylor instability arti numerical simulationsthe spatially modulated laser inertial confinement fusion icf spatially modulated laserthe acceleration phase spatially uniform
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Photoelectrocatalytic degradation of refractory organic pollutants in water:Mechanism of active species generation by modulating the photoanode micro-interface
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作者 Yuhao Ma Yufei Zhou +4 位作者 Hongli Li Cheng Fang Mingchuan Yu Shaoxia Yang Junfeng Niu 《Chinese Chemical Letters》 2026年第1期198-207,共10页
The escalating global issues of water scarcity and pollution emphasize the critical need for the rapid development of efficient and eco-friendly water treatment technologies.Photoelectrocatalytic technology has emerge... The escalating global issues of water scarcity and pollution emphasize the critical need for the rapid development of efficient and eco-friendly water treatment technologies.Photoelectrocatalytic technology has emerged as a promising solution for effectively degrading refractory organic pollutants in water under light conditions.This review delves into the advancements made in the field,focusing on strategies to enhance the generation of active species by modulating the micro-interface of the photoanode.Strategies,such as morphological control,element doping,introduction of surface oxygen vacancies,and construction of heterostructures,significantly improve the separation efficiency of photogenerated charges and the generation of active species,thereby boosting the efficiency of photoelectrocatalytic performance.Furthermore,the review explores the potential applications of photoelectrocatalytic technology in organic pollutant degradation in solutions.It also outlines the current challenges and future development directions.Despite its remarkable laboratory success,practical implementation of photoelectrocatalytic technology encounters obstacles related to stability,cost-effectiveness,and operational efficiency.Future investigations need to focus on optimizing the performance of photoelectrocatalytic materials and exploring strategies for upscaling their application in real water treatment scenarios. 展开更多
关键词 Photoelectrocatalytic degradation PHOTOANODE Interface modulation Active species MECHANISM
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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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Cannabidiol extending beyond neuroprotection toward neuronal repair:A potential regenerative modulator
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作者 María Salud García-Gutiérrez Jorge Manzanares 《Neural Regeneration Research》 2026年第8期3565-3566,共2页
Cannabidiol(CBD),the second most significant phytocannabinoid in the plant Cannabis sativa,which lacks potential as a drug of abuse(Viudez-Martinez et al.,2019),has gained widespread attention due to its anti-inflamma... Cannabidiol(CBD),the second most significant phytocannabinoid in the plant Cannabis sativa,which lacks potential as a drug of abuse(Viudez-Martinez et al.,2019),has gained widespread attention due to its anti-inflammatory,antioxidant,and antidepressant properties(Garci a-Gutierrez et al.,2020).Additionally,CBD exhibits neuroprotective properties,preserving neuronal viability and function by preventing or limiting cellular damage.Our team has demonstrated that CBD produces rapid antidepressant-like effects in a murine model of chronic mild stress,restoring hippocampal expression of brain-derived neurotrophic factor(BDNF). 展开更多
关键词 CANNABIDIOL regenerative modulator neuronal repair anti inflammatory cannabis sativawhich antioxidant NEUROPROTECTION antidepressant
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Nitrogen-doped carbon-support interaction induced d-orbital rearrangement for enhanced sodium-ion storage
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作者 Yitong Sun Mingyu Lian +6 位作者 Xuejing Guo Jinlian Ma Kai Liu Zhengqing Ye Xin Zhang Ying Jiang Lianqi Zhang 《Journal of Energy Chemistry》 2026年第1期435-443,I0010,共10页
Zinc telluride(ZnTe)with high density and low cost is considered as promising anode for sodium-ion batteries.However,ZnTe suffers from continuous capacity degradation owing to the low electronic conductivity,large vol... Zinc telluride(ZnTe)with high density and low cost is considered as promising anode for sodium-ion batteries.However,ZnTe suffers from continuous capacity degradation owing to the low electronic conductivity,large volume expansion,and high ion-diffusion energy barriers.Herein,the nitrogen-doped carbon confined ZnTe polyhedron heterostructure(ZnTe/NC)is proposed,exploiting its orbital rehybridization and the realignment of energy level to improve storage performance.Systematic ex situ/in situ characterizations and simulations demonstrated that the elaborate ZnTe/NC offers abundant electron/ion transport pathways,accelerates Na^(+)diffusion kinetics,and alleviates huge volume expansion.Notably,the nitrogen-doped carbon-support interaction induced via electron transfer between ZnTe sites and support elevates the energy level of Zn 3d orbital,greatly enhancing ion adsorption capability and reducing the ion diffusion barrier.As a result,the ZnTe/NC anode delivers a high discharge capacity of 470.5 mAh g^(−1)and long cycling durability over 1000 cycles.This work uncovers that optimizing sodium ion adsorption and diffusion via d-orbital energy level modulation enabled by nitrogen-doped support interaction is an effective method for developing high-performance transition metal telluride anodes for alkali ion storage. 展开更多
关键词 Sodium-ion battery Nitrogen-doped carbon Zinc telluride HETEROSTRUCTURE D-orbital modulation
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Rhodanine-based film-forming kinetic modulators unlock over 17%efficiency in all-small-molecule organic solar cells
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作者 Duoling Cao Lian Zhong +8 位作者 Zhe Sun Jintong Sun Xianqiang Xie Laju Bu Qianguang Yang Weijie Ding Changduk Yang Jing Li Shirong Lu 《Journal of Energy Chemistry》 2026年第2期761-770,I0016,共11页
Controlling film morphology remains an inherent challenge limiting the performance of all-smallmolecule organic solar cells(ASM-OSCs),primarily due to excessive donor-acceptor compatibility restricting further improve... Controlling film morphology remains an inherent challenge limiting the performance of all-smallmolecule organic solar cells(ASM-OSCs),primarily due to excessive donor-acceptor compatibility restricting further improvements.Here,we introduce a novel strategy employing rhodanine-based film-forming kinetic modulators-specifically tailored for the high-performance donor BTR-Clincluding 3-methylrhodanine(C1),3-ethylrhodanine(C2),3-buty lr hod a nine(C4),and 3-hexylrhodanine(C6).We demonstrate that the C2 modulator uniquely optimizes morphology by extending film-formation time and fine-tuning donor-acceptor miscibility,leading to enhanced molecular ordering,uniform vertical distributio n,and optimal phase sepa ration.This synergistic morphological control significantly boosts BTR-Cl crystallinity and facilitates efficient three-dimensional charge transport networks.Consequently,C2-treated BTR-Cl:N3 ASM-OSCs achieve an outstanding power conversion efficiency(PCE)of 17.12%,ranking among the highest reported for this system.Crucially,this work introduces a novel"donor-modulator structural matching"strategy,providing a powerful new avenue for controlling film-forming kinetics to realize high-performance ASM-OSCs. 展开更多
关键词 Modulators Organic solar cells All-small-molecule Morphology control
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Design,Realization,and Evaluation of Faster End-to-End Data Transmission over Voice Channels
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作者 Jian Huang Ming weiLi +2 位作者 Yulong Tian Yi Yao Hao Han 《Computers, Materials & Continua》 2026年第4期1650-1675,共26页
With the popularization of new technologies,telephone fraud has become the main means of stealing money and personal identity information.Taking inspiration from the website authentication mechanism,we propose an end-... With the popularization of new technologies,telephone fraud has become the main means of stealing money and personal identity information.Taking inspiration from the website authentication mechanism,we propose an end-to-end datamodem scheme that transmits the caller’s digital certificates through a voice channel for the recipient to verify the caller’s identity.Encoding useful information through voice channels is very difficult without the assistance of telecommunications providers.For example,speech activity detection may quickly classify encoded signals as nonspeech signals and reject input waveforms.To address this issue,we propose a novel modulation method based on linear frequency modulation that encodes 3 bits per symbol by varying its frequency,shape,and phase,alongside a lightweightMobileNetV3-Small-based demodulator for efficient and accurate signal decoding on resource-constrained devices.This method leverages the unique characteristics of linear frequency modulation signals,making them more easily transmitted and decoded in speech channels.To ensure reliable data delivery over unstable voice links,we further introduce a robust framing scheme with delimiter-based synchronization,a sample-level position remedying algorithm,and a feedback-driven retransmission mechanism.We have validated the feasibility and performance of our system through expanded real-world evaluations,demonstrating that it outperforms existing advanced methods in terms of robustness and data transfer rate.This technology establishes the foundational infrastructure for reliable certificate delivery over voice channels,which is crucial for achieving strong caller authentication and preventing telephone fraud at its root cause. 展开更多
关键词 Deep learning modulation CHIRP data over voice
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An attention module integrated hybrid model for recognizing microseismic signals induced by high-pressure grouting in deep rock layers
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作者 Yongshu Zhang Lianchong Li +2 位作者 Wenqiang Mu Jian Chen Peng Chen 《International Journal of Mining Science and Technology》 2026年第3期595-613,共19页
Microseismic(MS)monitoring is an effective technique to detect mining-induced rock fractures.However,recognizing grouting-induced signals is challenging due to complex geological conditions in deep rock plates.Therefo... Microseismic(MS)monitoring is an effective technique to detect mining-induced rock fractures.However,recognizing grouting-induced signals is challenging due to complex geological conditions in deep rock plates.Therefore,a hybrid model(WM-ResNet50)integrating data enhancement,a deep convolutional neural network(CNN),and convolutional block attention modules(CBAM)was proposed.Firstly,an MS system was established at the Xieqiao coal mine in Anhui Province,China.MS waveforms and injection parameters were acquired during grouting.Secondly,signals were categorized based on time-frequency characteristics to build a dataset,which was divided into training,validation,and test sets at a ratio of 4:1:1.Subsequently,the performance of WM-ResNet50 was evaluated based on indices such as individual precision,total accuracy,recall,and loss function.The results indicated that WMResNet50 achieved an average recognition accuracy of 94.38%,surpassing that of a simple CNN(90.04%),ResNet18(91.72%),and ResNet50(92.48%).Finally,WM-ResNet50 was applied to monitor the whole process at laboratory tests and field cases.Both results affirmed the feasibility and effectiveness of MS inversion in predicting actual slurry diffusion ranges within deep rock layers.By comparison,it was revealed that the MS sources classified by WM-ResNet50 matched grouting records well.A solution to address insufficient diffusion under long-borehole grouting has been proposed.WM-ResNet50′s accuracy was validated through in-situ coring and XRD analysis for cement-based hydration products.This study provides a beneficial reference for similar rock signal processing and in-field grouting practices. 展开更多
关键词 Attention module Convolutional neural network Microseismic ROCK Grouting-induced signals Slurry diffusion
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Pharmacological and light-driven pupillary accommodation in guinea pigs:comparative effects of muscarinic modulators and illumination across developmental stages
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作者 Hao Wu Na Lu +5 位作者 Zhong-Bao Qiao Chi Cheng Wen-Ting Luo Ting Wan Tong Qiao Yue Di 《International Journal of Ophthalmology(English edition)》 2026年第2期211-218,共8页
AIM:To investigate the effects of different light intensities and various mydriatic and miotic drugs on pupil accommodation in guinea pigs.METHODS:Forty-two-week-old guinea pigs were randomly divided into four groups ... AIM:To investigate the effects of different light intensities and various mydriatic and miotic drugs on pupil accommodation in guinea pigs.METHODS:Forty-two-week-old guinea pigs were randomly divided into four groups to assess pupillary responses under varying light intensities(100,250,500 lx)and pharmacological interventions(1%atropine,1%cyclopentolate,1%tropicamide,or 2%pilocarpine).Baseline pupil size and eccentricity were recorded using a non-contact Python-based imaging system integrating edge detection and pixel-to-distance conversion.Direct illumination effects were measured at sequential time points,followed by drug administration and longitudinal tracking of pupillary changes.The protocol was repeated at 12wk of age for developmental comparisons.Postexperiment,enucleated eyes were analyzed to evaluate in vitro vs in vivo differences.RESULTS:Significant age-dependent differences in pupil dynamics were observed.Both 2-and 12-week-old guinea pigs exhibited marked pupil constriction under direct illumination(P<0.001),with decreased eccentricity post-constriction(P<0.001).Indirect illumination caused inconsistent pupil size changes(2-week:P=0.68;12-week:P=0.49).Pharmacologically,atropine,cyclopentolate,and tropicamide induced pupil dilation(P<0.001),whereas pilocarpine caused constriction(P<0.001).All drug groups showed reduced eccentricity(P<0.001).In vivo/in vitro comparisons revealed significant structural differences.CONCLUSION:This study investigates pupillary responses in developing guinea pigs,revealing a direct pupillary light reflex(PLR)with light intensity-dependent responses,while indirect PLR was undetectable.The differential effects of muscarinic modulators on pupillary responses underscore the critical role of cholinergic signaling in ocular accommodation,with age-related variations in sensitivity.Additionally,a novel non-contact measurement methodology achieved a precision of 0.01 mm for pupillary quantification,enhancing accuracy in ocular studies. 展开更多
关键词 PUPIL guinea pig muscarinic receptor modulator light reflex
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Asymmetric triple-atomic sites with modulated electronic structure toward boosted peroxymonosulfate activation
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作者 Jinxin Li Yifan Ren +4 位作者 Jianan Gao Nadeeshani Nanayakkara Xin Wang Meng Liu Yanbiao Liu 《Chinese Chemical Letters》 2026年第2期698-703,共6页
Peroxymonosulfate(PMS)-based advanced oxidation technology has been proven to be a viable option for the decontamination of organic pollutants from water bodies.Advanced catalyst design is essential to this technology... Peroxymonosulfate(PMS)-based advanced oxidation technology has been proven to be a viable option for the decontamination of organic pollutants from water bodies.Advanced catalyst design is essential to this technology.Herein,a vanadium-doped LaFeO_(3) perovskite(LFO-V)featuring asymmetric Fe-O-V sites was rationally designed.Thanks to orbital electron interaction between Fe and V atoms,the modified electronic structure elevated electron density near the Fermi energy level while reducing the energy barrier toward effective PMS activation.This facilitated concurrent PMS reduction at the Fe sites to generate SO_(4)^(·-)and·OH(57.7%),and PMS oxidation at V sites to produce ^(1)O_(2)(42.3%).The LFO-V/PMS system demonstrated excellent tetracycline(TC)degradation performance with a 2-fold enhancement in rate constant compared to that of pristine LFO.Further,the LFO-V maintained long-term stability,and the toxicity of degradation intermediates was evaluated through microbial metabolomics.This work establishes an effective route to regulate the PMS activation pathways through precise electronic structure modulation,advancing the rational design of advanced Fenton-like catalysts. 展开更多
关键词 Electric structure modulation Fe-O-V sites Reduction-oxidation Radical species Non-radical species
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Pressure-induced tunable photoluminescence of Mn-doped post-perovskites(TDMP)PbBr_(4)
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作者 Ruijing Fu Junpeng Gao +4 位作者 Lingrui Wang Bin Xiao Guangxia Wang Qingguang Zeng Guanjun Xiao 《Chinese Chemical Letters》 2026年第2期536-539,共4页
One-dimensional(1D)organic-inorganic halide perovskites have produced significant research interest due to their unique structure and superior tunable luminescence properties.Here,we successfully achieved a unique col... One-dimensional(1D)organic-inorganic halide perovskites have produced significant research interest due to their unique structure and superior tunable luminescence properties.Here,we successfully achieved a unique color-tunable phenomenon of Mn-doped 1D post-perovskite(TDMP)PbBr_(4)(TDMP=trans-2,5-dimethylpiperazine)(TPBM-14)under high pressure.Which exhibited tunable photoluminescence(PL)emission from red to yellow orange.Meanwhile,the band gap continued to decrease below 20.0 GPa,accompanied by piezochromism,which was associated the shrinkage and distortion of inorganic,which enhances the crystal field splitting energy and reduces the energy gap of the ^(4)T_(1) to ^(6)A_(1) transition.The unique octahedral corner-and edge-sharing structure of(TDMP)PbBr_(4),the synergistic effect of Mn doping and pressure induces local lattice distortion in TPBM-14,leading to a significant enhancement of the STE emission at 8.1 GPa.Our research explores the intrinsic connection between the band structure and optical properties of TPBM-14 under high pressure and offers valuable insights for performance optimization. 展开更多
关键词 High pressure Piezochromism Mn-doped perovskite Emission color modulation One-dimensional organic-inorganic halide PEROVSKITE
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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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Investigation of a Closed-Loop Electrohydraulic System Driven by a Variable Frequency Drive Based on a Programmable Logic Controller
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作者 Aws F.Hassan Jamal A.-K.Mohammed Walaa M.Hashim 《Energy Engineering》 2026年第4期404-429,共26页
The current study aims to improve the performance of the electrohydraulic servo system(EHSS)by increasing the volumetric efficiency of the pump and reducing electrical power consumption to a minimum value.An experimen... The current study aims to improve the performance of the electrohydraulic servo system(EHSS)by increasing the volumetric efficiency of the pump and reducing electrical power consumption to a minimum value.An experimental setup has been designed and built to control the cylinder position using a programmable logic controller to provide the appropriate motor speed from the AC drive to control the velocity of the hydraulic actuator;the induction motor is driven by an AC drive using a tune proportional-integral-variable frequency drive(TPI-VFD)space vector modulation(SVM)hybrid technology.Theoretically,it was analyzed and simulated by MATLAB,which showed that the starting current was reduced by 81%compared to the traditional system.Also,the settling time of the system decreased to 0.35 s to reach a steady state with a minimum error of 0.03 and an overshoot of 0.3%.On the other hand,the experimental results of the EHSS show that the three-phase induction motor with a closed-loop speed control AC drive with a programmable logic controller PLC based system is the best case for determining the appropriate operating speed.The optimum speed,frequency,and voltage were 1325.3 rpm,46.6 Hz,and 354.16 V.In addition,enhancement is achieved in closed-loop VFD-PLC,where at 6.5 bar pressure and 3.4 LPM flow,the volumetric efficiency after the pump improves to 98.6%while it reaches 96.3%before the cylinder at a flow rate of 3.32 LPM.Finally,in the closed-loop VFD-PLC in the expansion stroke,the rated electrical power consumption of the three-phase IM decreased to 532 W at the speed of 1325.3 rpm,resulting in energy savings of 20.6%. 展开更多
关键词 Electro-hydraulic servo system three-phase IM VFDPLC space vector modulation energy saving volumetric efficiency
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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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