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Bioinspired smart dual-layer hydrogels system with synchronous solar and thermal radiation modulation for energy-saving all-season temperature regulation 被引量:1
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作者 Meng-Chen Huang Chao-Hua Xue +8 位作者 Zhongxue Bai Jun Cheng Yong-Gang Wu Chao-Qun Ma Li Wan Long Xie Hui-Di Wang Bing-Ying Liu Xiao-Jing Guo 《Journal of Energy Chemistry》 2025年第2期175-190,I0005,共17页
All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management... All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature condition.Herein,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel)system was subtly created though an"on-demand"dual-layer structure design strategy.The PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating regulation.Furthermore,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74)and thermal emissivity(ΔE=0.52)in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃in summer and 6.1℃in winter,respectively.Moreover,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and climates.This novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons. 展开更多
关键词 Thermochromic hydrogel Self-adaptive thermal management Radiative cooling Spectral modulation ENERGY-SAVING
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Design of Serially Concatenated Two-Level Polar Coded Modulation System with Low-Complexity
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作者 Zhou Lin Liao Guojun +3 位作者 Xu Lei An Ran Xie Xianzhong Wang Xi 《China Communications》 2025年第1期102-110,共9页
Multilevel coding(MLC)is a commonly used polar coded modulation scheme,but challenging to implement in engineering due to its high complexity and long decoding delay for high-order modulations.To address these limitat... Multilevel coding(MLC)is a commonly used polar coded modulation scheme,but challenging to implement in engineering due to its high complexity and long decoding delay for high-order modulations.To address these limitations,a novel two-level serially concatenated MLC scheme,in which the bitlevels with similar reliability are bundled and transmitted together,is proposed.The proposed scheme hierarchically protects the two bit-level sets:the bitlevel sets at the higher level are sufficiently reliable and do not require excessive resources for protection,whereas only the bit-level sets at the lower level are encoded by polar codes.The proposed scheme has the advantages of low power consumption,low delay and high reliability.Moreover,an optimized constellation signal labeling rule that can enhance the performance is proposed.Finally,the superiority of the proposed scheme is validated through the theoretical analysis and simulation results.Compared with the bit interleaving coding modulation(BICM)scheme,under 256-quadrature amplitude modulation(QAM),the proposed scheme attains a performance gain of 1.0 dB while reducing the decoding complexity by 54.55%. 展开更多
关键词 bit-interleaved coded modulation high-order modulation multilevel coding polar codes
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M2 macrophages-derived exosomes for osteonecrosis of femoral head treatment:modulating neutrophil extracellular traps formation and endothelial phenotype transition
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作者 Guanzhi Liu Ruomu Cao +5 位作者 Qimeng Liu Heng Li Peng Yan Kunzheng Wang Run Tian Pei Yang 《Bone Research》 2025年第4期855-865,共11页
Exosomes have shown good potential in ischemic injury disease treatments.However,evidence about their effect and molecular mechanisms in osteonecrosis of femoral head(ONFH)treatment is still limited.Here,we revealed t... Exosomes have shown good potential in ischemic injury disease treatments.However,evidence about their effect and molecular mechanisms in osteonecrosis of femoral head(ONFH)treatment is still limited.Here,we revealed the cell biology characters of ONFH osteonecrosis area bone tissue in single cell scale and thus identified a novel ONFH treatment approach based on M2 macrophages-derived exosomes(M2-Exos).We further show that M2-Exos are highly effective in the treatment of ONFH by modulating the phenotypes communication between neutrophil and endothelium including neutrophil extracellular traps formation and endothelial phenotype transition.Additionally,we identified that M2-Exos’therapeutic effect is attributed to the high content of miR-93-5p and constructed miR-93-5p overexpression model in vitro and in vivo based on lentivirus and adenoassociated virus respectively.Then we found miR-93-5p can not only reduce neutrophil extracellular traps formation but also improve angiogenic ability of endothelial cells.These results provided a new theoretical basis for the clinical application of ONFH therapeutic exosomes. 展开更多
关键词 modulating phenotypes comm cell biology characters ischemic injury disease miR p osteonecrosis femoral neutrophil extracellular traps macrophages derived exosomes endothelial phenotype transition
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Periodic modulation of adiabatic dynamics in non-reciprocal Landau-Zener systems
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作者 Rong Chang Sheng-Chang Li 《Chinese Physics B》 2025年第3期259-264,共6页
The control of adiabatic dynamics is essential for quantum manipulation.We investigate the effects of both periodic modulating field and linear sweeping field on adiabatic dynamics based on a non-reciprocal Landau-Zen... The control of adiabatic dynamics is essential for quantum manipulation.We investigate the effects of both periodic modulating field and linear sweeping field on adiabatic dynamics based on a non-reciprocal Landau-Zener model with periodic modulation.We obtain adiabatic phase diagrams in the(ω,δ)parameter space,where the adiabatic region is bounded by the modulating frequencyωgreater than a critical valueω_(c) and the non-reciprocal parameterδless than one.The results show that the adiabaticity of the system is not sensitive to the modulating amplitude.We find that the critical modulating frequency can be expressed as a power function of the modulating period number or the sweeping rate.Our findings suggest that one can change the adiabatic region or improve the adiabaticity by adjusting the parameters of both the modulating and the sweeping fields,which provides an effective means to flexibly control the adiabatic dynamics of non-reciprocal systems. 展开更多
关键词 ADIABATICITY non-reciprocity Landau-Zener tunneling periodic modulation
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Role of autophagy in rejection after solid organ transplantation:A systematic review of the literature
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作者 Shu-Min Jiang Xue-Jiao Li +4 位作者 Zi-Lin Wang Zhi-Wei Chen Zhi-Long Liu Qiang Li Xiao-Long Chen 《World Journal of Transplantation》 2025年第3期79-90,共12页
Organ transplantation has long been recognized as an effective treatment for endstage organ failure,metabolic diseases,and malignant tumors.However,graft rejection caused by major histocompatibility complex mismatch r... Organ transplantation has long been recognized as an effective treatment for endstage organ failure,metabolic diseases,and malignant tumors.However,graft rejection caused by major histocompatibility complex mismatch remains a significant challenge.While modern immunosuppressants have made significant strides in reducing the incidence and risk of rejection,they have not been able to eliminate it completely.The intricate mechanisms underlying transplant rejection have been the subject of intense investigation by transplant immunologists.Among these factors,autophagy has emerged as a key player.Autophagy is an evolutionarily conserved mechanism in eukaryotic cells that mediates autophagocytosis and cellular protection.This process is regulated by autophagy-related genes and their encoded protein families,which maintain the material and energetic balance within cells.Additionally,autophagy has been reported to play crucial roles in the development,maturation,differentiation,and responses of immune cells.In the complex immune environment following transplantation,the role and mechanisms of autophagy are gradually being revealed.In this review,we aim to explore the current understanding of the role of autophagy in solid organ rejection after transplantation.Furthermore,we delve into the therapeutic advancements achieved by targeting autophagy involved in the rejection process. 展开更多
关键词 AUTOPHAGY Organ transplantation Graft rejection IMMUNITY Immune modulation
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Design and Implementation of Closed-Loop Control of Vector Force in Static Push-the-bit Rotary Steering System
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作者 Liang Yao Kang Hong-bo +4 位作者 Liu Yue Chen wen Sun Yan Ma Li Zhao Yan-Wei 《Applied Geophysics》 2025年第3期796-803,896,共9页
Rotary steering systems(RSSs)have been increasingly used to develop horizontal wells.A static push-the-bit RSS uses three hydraulic modules with varying degrees of expansion and contraction to achieve changes in the p... Rotary steering systems(RSSs)have been increasingly used to develop horizontal wells.A static push-the-bit RSS uses three hydraulic modules with varying degrees of expansion and contraction to achieve changes in the pushing force acting on the wellbore in different sizes and directions within a circular range,ultimately allowing the wellbore trajectory to be drilled in a predetermined direction.By analyzing its mathematical principles and the actual characteristics of the instrument,a vector force closed-loop control method,including steering and holding modes,was designed.The adjustment criteria for the three hydraulic modules are determined to achieve rapid adjustment of the vector force.The theoretical feasibility of the developed method was verified by comparing its results with the on-site application data of an imported rotary guidance system. 展开更多
关键词 Static push-the-bit hydraulic modules closed-loop control vector force working mode
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Efficacy of clomiphene citrate and tamoxifen on pregnancy rates in idiopathic male subfertility:A systematic review and meta-analysis
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作者 Shadi Khashaba Shehab Khashaba +5 位作者 Anil Krishan Angus Bruce Abdullatif Almaghlouth Jason Huang Mahmoud Mima Craig Niederberger 《Asian Journal of Urology》 2025年第1期15-22,共8页
Objective Selective estrogen receptor modulators(SERMs)have demonstrated efficacy in the treatment of hypogonadism in males and male factor infertility.Two SERMs,clomiphene citrate and tamoxifen,are now prescribed for... Objective Selective estrogen receptor modulators(SERMs)have demonstrated efficacy in the treatment of hypogonadism in males and male factor infertility.Two SERMs,clomiphene citrate and tamoxifen,are now prescribed for off-label use to treat both conditions in males.However,existing literature compares mixed protocols with active management.We aimed to conduct a meta-analysis to evaluate the effect of clomiphene and tamoxifen versus placebo on natural pregnancy rates.Methods We conducted a comprehensive systematic review of electronic databases:MEDLINE,PubMed/PMC,EMBASE,CINAHL,Cochrane Central Register of Controlled Trials(CENTRAL),Scopus,Google Scholar,and Web of Science.Articles satisfying all selection criteria were analyzed.The primary outcome was the incidence of pregnancy after receiving the treatment.Secondary outcomes included serum follicle-stimulating hormone,luteinizing hormone,and testosterone levels,and sperm count and motility.We calculated the pooled odds ratio,risk ratio,and risk difference to ascertain possible alterations in the direction of the pooled effect size.Results Ten randomized controlled trials were ultimately included and underwent data extraction.Clomiphene citrate and placebo groups had similar pregnancy rates(10.4%and 7.1%,respectively;odds ratio 1.30[95%confidence interval 0.27–6.17];p=0.74).No meta-analysis could be calculated for pregnancy rates in tamoxifen versus placebo groups.Heterogeneity among the studies of both SERMs ranged from low to high.Conclusion Although clomiphene citrate and tamoxifen are often used off-label for the treatment of male infertility secondary to hypogonadism,studies of SERMs in the treatment of idiopathic male factor infertility are limited and heterogenous,preventing this meta-analysis from investigating the efficacy of SERMs on male infertility.The effect of clomiphene citrate or tamoxifen on the pregnancy rate remains uncertain. 展开更多
关键词 Male fertility Male infertility Clomiphene citrate TAMOXIFEN Selective estrogen receptor modulator
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Index Modulation Aided OTFS for SCMA System
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作者 He Chunlin Xiao Lixia +3 位作者 Li Shuo Liu Weidan Xiao Pei Jiang Tao 《China Communications》 2025年第8期19-28,共10页
In this paper,an index modulation(IM)aided uplink orthogonal time frequency space modulation(OTFS)structure for sparse code multiple access(SCMA)is proposed.To be more specific,the information bits are firstly partiti... In this paper,an index modulation(IM)aided uplink orthogonal time frequency space modulation(OTFS)structure for sparse code multiple access(SCMA)is proposed.To be more specific,the information bits are firstly partitioned for transmit antenna(TA)selection and sparse codeword mapping,respectively.Subsequently,the codewords deployed on the 2-dimensional(2D)delay-Doppler(DD)plane are transmitted by the selected TA,and the superimposed signals are jointly detected at the receiver.Furthermore,a low-complexity zero-embedded expectation propagation(ZE-EP)detector is conceived,where the codebooks are extended with zero vectors to reflect the silent indices.The simulation results demonstrate that the proposed IM-OTFS-SCMA system is capable of providing significant performance gain over the OTFS-SCMA counterpart. 展开更多
关键词 expectation propagation algorithm index modulation message passing algorithm OTFS SCMA
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Multiple Parallel RIS-Assisted MU-MIMO-DQSM System:Blind and Intelligent Approaches
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作者 Francisco R.Castillo-Soria Sharon Macias-Velasquez +2 位作者 Kumaravelu Vinoth Babu Ramos Victor Cesar A.Azurdia-Meza 《China Communications》 2025年第8期29-43,共15页
New communication systems require high spectral and energy efficiencies to meet the growing demand for services in future networks.In this paper,an efficient multiple parallel reconfigurable intelligent surfaces(RIS)-... New communication systems require high spectral and energy efficiencies to meet the growing demand for services in future networks.In this paper,an efficient multiple parallel reconfigurable intelligent surfaces(RIS)-assisted multiuser(MU) multiple input-multiple output(MIMO) double quadrature spatial modulation(DQSM) downlink transmission system is presented.In the transmitter,the proposed N-RIS-MU-MIMO-DQSM system uses a modified block diagonalization technique and a genetic algorithm(GA) to jointly design the precoding signals required at the base station(BS) and the optimal phase changes required at multiple RISs.A reduced detection complexity and improved bit error rate(BER) performance are achieved by incorporating spatial modulation.The proposed system is compared under the same conditions and parameters with two reference systems,considering blind and optimized RISs approaches over correlated Rayleigh fading channels.Results show that compared with a similar system that does not use RISs,the proposed system has up to30 dB gain in BER performance.Compared with a similar system based on conventional quadrature amplitude modulation(QAM),the proposed system has gains of up to 2-3 dB in BER performance and up to 55.8% lower detection complexity for the analyzed cases. 展开更多
关键词 genetic algorithms multiple RIS multiuser MIMO spatial modulation
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Designing and optimizing an intelligent self-powered condition monitoring system for mining belt conveyor idlers and its application
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作者 Xuanbo JIAO Zhixia WANG +2 位作者 Wei WANG F.S.GU S.HEYNS 《Applied Mathematics and Mechanics(English Edition)》 2025年第9期1679-1698,共20页
Belt conveyors are extensively utilized in mining and power industries.In a typical coal mine conveyor system,coal is transported over distances exceeding 2 km,involving more than 20000 idlers,which far exceeds a reas... Belt conveyors are extensively utilized in mining and power industries.In a typical coal mine conveyor system,coal is transported over distances exceeding 2 km,involving more than 20000 idlers,which far exceeds a reasonable manual inspection capacity.Given that idlers typically have a lifespan of 1-2 years,there is an urgent need for a rapid,cost-effective,and intelligent safety monitoring system.However,current embedded systems face prohibitive replacement costs,while conventional monitoring technologies suffer from inefficiency at low rotational speeds and lack systematic structural optimization frameworks for diverse idler types and parameters.To address these challenges,this paper introduces an integrated,on-site detachable self-powered idler condition monitoring system(ICMS).This system combines energy harvesting based on the magnetic modulation technology with wireless condition monitoring capabilities.Specifically,it develops a data-driven model integrating convolutional neural networks(CNNs) with genetic algorithms(GAs).The conventional testing results show that the data-driven model not only significantly accelerates the parameter response time,but also achieves a prediction accuracy of 92.95%.The in-situ experiments conducted in coal mines demonstrate the system's reliability and monitoring functionality under both no-load and fullload conditions.This research provides an innovative self-powered condition monitoring solution and develops an efficient data-driven model,offering feasible online monitoring approaches for smart mine construction. 展开更多
关键词 intelligent safety monitoring SELF-POWERED magnetic modulation data driven model mining conveyor
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High-Frequency Stable Wireless Amplitude Modulation System Based on a Pierce Circuit
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作者 Huiwen Xu 《Journal of Electronic Research and Application》 2025年第5期61-70,共10页
This paper designs a high-frequency stable wireless amplitude modulation(AM)system based on a Pierce circuit.The system utilizes an oscillator and comparator to generate a 20 kHz square wave with an adjustable duty cy... This paper designs a high-frequency stable wireless amplitude modulation(AM)system based on a Pierce circuit.The system utilizes an oscillator and comparator to generate a 20 kHz square wave with an adjustable duty cycle,combined with a 41 MHz carrier wave produced by a passive crystal oscillator Pierce circuit.A 100% modulation index amplitude modulation is achieved through the AD835 multiplier.The modulated signal is amplified by a power amplifier circuit and transmitted wirelessly via the transmitter antenna.Upon reception,the signal undergoes two-stage highfrequency amplification before passing through a Schottky diode envelope detector.The NE5532 shaping circuit then restores the square wave.Experimental results demonstrate reliable 11-meter transmission with carrier frequency deviation<0.75% and demodulation error<1%. 展开更多
关键词 Wireless transmission Amplitude modulation Pierce circuit Low power consumption
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Anti-interference methods for narrowband and repeater-modulation interference in airborne SAR systems
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作者 Kai Chen Yong-Bo Zhao +3 位作者 Kai Jiang Long Sun Kun Deng Chang-Chun Ding 《Journal of Electronic Science and Technology》 2025年第3期1-12,共12页
With the advancement of electronic countermeasures,airborne synthetic aperture radar(SAR)systems are facing increasing challenges in maintaining effective performance in hostile environments.In particular,high-power i... With the advancement of electronic countermeasures,airborne synthetic aperture radar(SAR)systems are facing increasing challenges in maintaining effective performance in hostile environments.In particular,high-power interference can severely degrade SAR imaging and signal processing,often rendering target detection impossible.This highlights the urgent need for robust anti-interference solutions in both the signal processing and image processing domains.While current methods address interference across various domains,techniques such as waveform modification and spatial filtering typically increase the system costs and complexity.To overcome these limitations,we propose a novel approach that leverages the multi-domain characteristics of interference to efficiently suppress narrowband interference and repeater modulation interference.Specifically,narrowband interference is mitigated using notch filtering,a signal processing technique that effectively filters out unwanted frequencies,while repeater modulation interference is addressed through strong signal amplitude normalization,which enhances both the signal and image processing quality.These methods were validated through tests on real SAR data,demonstrating significant improvements in the imaging performance and system robustness.Our approach offers valuable insights for advancing anti-interference technologies in SAR systems and provides a cost-effective solution to enhance their resilience in complex electronic warfare environments. 展开更多
关键词 Airborne radar Narrowband interference Repeater modulation interference Signal and image processing ANTI-INTERFERENCE
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Design and implementation of an integrated and rapidly assembled infrared three-band optical system
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作者 Shuanglong Tan Yulin Wang +3 位作者 Guangwei Shi Shuaiwei Mu Xin Zhang Lin Ma 《Astronomical Techniques and Instruments》 2025年第2期88-99,共12页
Continuing advancement in astronomy,space exploration,and scientific detection,has increased demand for infrared multi-band detection systems.Traditional three-band optical systems,designed to simultaneously image at ... Continuing advancement in astronomy,space exploration,and scientific detection,has increased demand for infrared multi-band detection systems.Traditional three-band optical systems,designed to simultaneously image at infrared short-wave,mid-wave,and long-wave bands typically rely on dispersive elements,leading to bulky sizes,complex system architectures,low efficiency,and challenges in rapid assembly.To overcome these obstacles,in combination with the latest third-generation infrared detectors,we propose a design for a compact and lightweight three-band optical system,with infrared capabilities in all three required bands.The core of this approach is an integrated design philosophy that emphasizes the high steepness of mirror surfaces.This design achieves uniform correction and optimization of chromatic aberration and off-axis aberration across the spectral range.We introduce a novel integration of optical and mechanical elements to replace traditional assembly,reducing manufacturing and assembly errors,and degrees of freedom,associated with high-power optical elements.Confirming the effectiveness through a combination of simulations and experimental comparisons,the measured mid-wave full-field transfer function exceeds 0.405 at 17 lp/mm,satisfying the imaging requirements of the system.The optical system is lightweight and compact,with a total mass under 408 g and a compact volume of justΦ112 mm×117 mm.This serves as a valuable reference for the engineering application of high-performance,compact multi-band infrared composite detection systems for astronomy and space exploration. 展开更多
关键词 Three-band infrared INTEGRATED Rapid assembly Modulation Transfer Function(MTF)
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Modulating electronic structure of g-C_(3)N_(4) hosted Co-N_(4) active sites by axial phosphorus coordination for efficient overall H_(2)O_(2) photosynthesis from oxygen and water
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作者 Shinuo Liang Fengjun Li +2 位作者 Fei Huang Xinyu Wang Shengwei Liu 《Chinese Journal of Catalysis》 2025年第9期81-95,共15页
Single-atom catalysts are promising for H_(2)O_(2) photosynthesis from O_(2) and H_(2)O,but their efficiency is still limited by the ill-defined electronic structure.In this study,Co single-atoms with unique four plan... Single-atom catalysts are promising for H_(2)O_(2) photosynthesis from O_(2) and H_(2)O,but their efficiency is still limited by the ill-defined electronic structure.In this study,Co single-atoms with unique four planar N-coordination and one axial P-coordination(Co-N_(4)P_(1))are decorated on the lateral edges of nanorod-like crystalline g-C_(3)N_(4)(CCN)photocatalysts.Significantly,the electronic structures of central Co as active sites for O_(2) reduction reaction(ORR)and planar N-coordinator as active sites for H_(2)O oxidation reaction(WOR)in Co-N_(4)P_(1) can be well regulated by the synergetic effects of introducing axial P-coordinator,in contrast to the decorated Co single-atoms with only four planar N-coordination(Co-N_(4)).Specifically,directional photoelectron accumulation at central Co active sites,induced by an introduced midgap level in Co-N_(4)P_(1),mediates the ORR active sites from 4e–-ORR-selective terminal–NH_(2) sites to 2e–-ORR-selective Co sites,moreover,an elevated d-band center of Co 3d orbital strengthens ORR intermediate*OOH adsorption,thus jointly facilitating a highly selective and active 2e^(–)-ORR pathway to H_(2)O_(2) photosynthesis.Simultaneously,a downshifted p-band center of N_(2)p orbital in Co-N_(4)P_(1) weakens WOR intermediate*OH adsorption,thus enabling a preferable 2e^(–)-WOR pathway toward H_(2)O_(2) photosynthesis.Subsequently,Co-N_(4)P_(1) exhibits exceptional H_(2)O_(2) photosynthesis efficiency,reaching 295.6μmol g^(-1) h^(-1) with a remarkable solar-to-chemical conversion efficiency of 0.32%,which is 15 times that of Co-N_(4)(19.2μmol g^(-1) h^(-1))and 10 times higher than CCN(27.6μmol g^(-1) h^(-1)).This electronic structure modulation on single-atom catalysts offers a promising strategy for boosting the activity and selectivity of H_(2)O_(2) photosynthesis. 展开更多
关键词 Crystalline carbon nitride Coordination engineering Single atom Co-N_(4)P_(1)active sites modulating electronic structure Overall H_(2)O_(2)photosynthesis
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Adaptive Dispersion Estimation for Linearized Electronic Dispersion Compensation in IM-DD Systems
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作者 Huo Jiahao Tao Jianlong +3 位作者 Zhang Xiaoying Zhu Jin Qin Peng Wei Huangfu 《China Communications》 2025年第4期55-64,共10页
An adaptive dispersion estimation(ADE)is proposed to compensate dispersion and estimate the transfer function of the fiber channel with GerchbergSaxton(G-S)algorithm,using the stochastic gradient descent(SGD)method in... An adaptive dispersion estimation(ADE)is proposed to compensate dispersion and estimate the transfer function of the fiber channel with GerchbergSaxton(G-S)algorithm,using the stochastic gradient descent(SGD)method in the intensity-modulation and direct-detection(IM-DD)system,improving the tolerance of the algorithm to chromatic dispersion(CD).In order to address the divergence arising from the perturbation in the amplitude of the received signal caused by the filtering effect of the non-ideal channels,a channel-compensation equalizer(CCE)derived from the back-to-back(BTB)scenario is employed at the transmitter to make the amplitude of the received signal depicting the CD effect more accurately.The simulation results demonstrate the essentiality of CCE for the convergence and performance improvement of the G-S algorithm.Results show that it supports 112Gb/s four-level pulse amplitude modulation(PAM4)over 100 km standard single-mode fiber(SSMF)transmission under the 7%forward error correction(FEC)threshold of 3.8E-3.Besides,ADE improves the tolerance to wavelength drift from about 4 nm to 42 nm,and there is a better tolerance for fiber distance perturbation,indicating the G-S algorithm and its derived algorithms with the ADE scheme exhibit superior robustness to the perturbation in the system. 展开更多
关键词 chromatic dispersion digital signal process intensity modulation and direct detection
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New types of nondegenerate solitons for a(2+1)-dimensional coupled system
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作者 Yong Meng Hafiz Wajahat Ahmed Riaz Ji Lin 《Communications in Theoretical Physics》 2025年第9期1-9,共9页
In this paper,we investigate the(2+1)-dimensional three-component long-wave-short-wave resonance interaction system,which describes complex systems and nonlinear wave phenomena in physics.By employing the Hirota bilin... In this paper,we investigate the(2+1)-dimensional three-component long-wave-short-wave resonance interaction system,which describes complex systems and nonlinear wave phenomena in physics.By employing the Hirota bilinear method,we derive the general nondegenerate N-soliton solution of the system,where each short-wave component contains N arbitrary functions of the independent variable y.The presence of these arbitrary functions in the analytical solution enables the construction of a wide range of nondegenerate soliton types.Finally,we illustrate the structural features of several novel nondegenerate solitons,including M-shaped,multiple double-hump,and sawtooth double-striped solitons,as well as interactions between nondegenerate solitons,such as dromion-like solitons and solitoffs,with the aid of figures. 展开更多
关键词 (2+1)-dimensional coupled system general nondegenerate N-soliton solution arbitrary functions modulation waveform
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Lysophosphatidic acid signaling:Transmembrane modulators in the central nervous system
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作者 Alexandra Polyzou Alexandros Κ.Tsiouris +2 位作者 Charalampos Labrakakis Britta J.Eickholt George Leondaritis 《Neural Regeneration Research》 2026年第3期1104-1105,共2页
Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,includi... Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,including cerebrospinal fluid,varies significantly(Figure 1Α;Yung et al.,2014).LPA actually corresponds to a variety of lipid species that include different stereoisomers with either saturated or unsaturated fatty acids bearing likely differentiated biological activities(Figure 1Α;Yung et al.,2014;Hernández-Araiza et al.,2018). 展开更多
关键词 transmembrane modulators cerebrospinal fluidvaries variety lipid species lysophosphatidic acid biological fluidsincluding lysophosphatidic acid lpa saturated unsaturated fatty acids pleiotropic lipid agonist
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Research onπ/4QPSK Modulation Communication Transmission System and FPGA Implementation
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作者 Yuhui Chu Yunjie Yuan +2 位作者 Xiaolei Cai Yanyan Wang Peijie Yin 《Journal of Electronic Research and Application》 2025年第2期12-17,共6页
This paper examines theπ/4QPSK modulation communication transmission system,analyzing the performance advantages and disadvantages ofπ/4QPSK in comparison to QPSK.It also presents a comprehensive FPGA implementation... This paper examines theπ/4QPSK modulation communication transmission system,analyzing the performance advantages and disadvantages ofπ/4QPSK in comparison to QPSK.It also presents a comprehensive FPGA implementation scheme for a modulation communication transmission system,integrating RS channel coding,framing,frequency conversion,and other modules.This design is based on practical research and development requirements.The Xilinx Spartan6 chip board was used for board-level verification.Theπ/4QPSK modulated signal was transmitted via D/A conversion and radio frequency,with the transmitted waveform was looped back for reception.After A/D processing,the correctness of the designed modulation transmission scheme was verified. 展开更多
关键词 π/4QPSK modulation FPGA
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Investigation of edge states variation in valley photonic crystals by modulating the refractive index of domain walls
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作者 ZHANG Run ZHONG Xingli +2 位作者 LIN Zhongxi QIU Weibin SU Hui 《Optoelectronics Letters》 2025年第3期160-166,共7页
Realizing the valley Hall effect by breaking the spatial inversion symmetry of photonic systems has become a cutting-edge field of micro-nano-optics,since the valley degree of freedom was introduced into photonic syst... Realizing the valley Hall effect by breaking the spatial inversion symmetry of photonic systems has become a cutting-edge field of micro-nano-optics,since the valley degree of freedom was introduced into photonic system.Various novel devices based on the domain walls of the valley photonic crystals have also been demonstrated.In this article,we investigate the variation of edge states by the modulation of refractive index within the domain walls,and the geometric difference between the dielectric columns of the sublattices.Straight photonic crystal waveguides with three types of domain walls(bearded,zigzag,armchair)are constructed.Simulation results show that the creation of a double-edge state in the band diagram results in two windows of stable transmission in tunable bands.Our findings might have significant implications in the field of novel optical devices. 展开更多
关键词 modulation refractive index domain walls variation edge states breaking spatial inversion symmetry valley degree freedom photonic crystals geometric difference dielectric columns photonic systems
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Identification of linear continuous-time system using wavelet modulating filters 被引量:4
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作者 贺尚红 钟掘 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第3期270-277,共8页
An approach to identification of linear continuous-time system is studied with modulating functions. Based on wavelet analysis theory, the multi-resolution modulating functions are designed, and the corresponding filt... An approach to identification of linear continuous-time system is studied with modulating functions. Based on wavelet analysis theory, the multi-resolution modulating functions are designed, and the corresponding filters have been analyzed. Using linear modulating filters, we can obtain an identification model that is parameterized directly in continuous-time model parameters. By applying the results from discrete-time model identification to the obtained identification model, a continuous-time estimation method is developed. Considering the accuracy of parameter estimates, an instrumental variable (Ⅳ) method is proposed, and the design of modulating integral filter is discussed. The relationship between the accuracy of identification and the parameter of modulating filter is investigated, and some points about designing Gaussian wavelet modulating function are outlined. Finally, a simulation study is also included to verify the theoretical results. 展开更多
关键词 parameter estimation modulation function continuous-time system WAVELET Gaussian function.
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