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Optical and Network Performance Analysis of XGS-PON System over Active Co-Existence PON Systems 被引量:1
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作者 D. Tarsono A. Ahmad +4 位作者 K. A. Sharif M. H. Othman K. Khairi N. A. Ngah Z. A. Manaf 《Optics and Photonics Journal》 2017年第8期40-48,共9页
We proposed an enhanced Reach Extender (RE) called Active Co-existence (ACEX) and investigate its performance with respect to XGS-PON system that co-exist with GPON and TWDM-PON system. The RE is consists of hybrid op... We proposed an enhanced Reach Extender (RE) called Active Co-existence (ACEX) and investigate its performance with respect to XGS-PON system that co-exist with GPON and TWDM-PON system. The RE is consists of hybrid optical amplifier integrated (EDFA and SOA) with Co-existence Element (CEX) module which is installed at the Central Office (CO) together with the OLT system and act as a booster and pre-amplifier for the downstream and upstream optical signal respectively. The results show that the proposed ACEX is capable to support XGS-PON operation for a maximum distance of 35 km with 128 splitting ratio and up to 44 dB link loss. 展开更多
关键词 GPON XGS-PON TWDM-PON co-existence Element active co-existence Reach EXTENDER
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Comparative Risk of Stroke Associated with Active Smoking in Chinese and Asian Populations
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作者 Zemin Cai Xiaojing Guo +3 位作者 Xiao Zhang Danying Li Xiaoyue Li Xia Wan 《Biomedical and Environmental Sciences》 2026年第1期60-72,共13页
Objective Stroke is the third leading cause of death worldwide,with the highest incidence in Asia,particularly in China,where smoking remains a major risk factor.The smoking prevalence in China is similar to that in A... Objective Stroke is the third leading cause of death worldwide,with the highest incidence in Asia,particularly in China,where smoking remains a major risk factor.The smoking prevalence in China is similar to that in Asia.Whether the risk estimates for smoking-related stroke in China and all Asian countries are still unknown which is worth evaluating.Thus,this study aims to compare the Relative Risk(RR)of smoking-attributed stroke among the Chinese and Asian populations.Methods A literature search was conducted from the inception to September 10,2022.Studies meeting the criteria were included.The articles were screened,and related information was extracted.Pooled RRs stratified by smoking status and sex were analyzed,including subgroup analyses for China,other Asian countries,and Asia overall.Finally,publication bias and sensitivity analyses were conducted.Results Thirty-seven articles on the Chinese population and 15 on other Asian populations were included,with a mean Newcastle-Ottawa scale(NOS)score of 7.25.About ever smokers,there had no statistical difference existed in both sexes and females between China and other Asian countries,while the RR of males in other Asian countries[2.31(1.38,3.86)]was higher than that in China[1.21(1.15,1.26)];further subgroup analysis indicated that other Asian countries had higher RR[3.76(3.02,4.67)]in the morbidity subgroup.The RRs of both sexes,males and females,between China and the whole of Asia were not statistically different.As for current and former smokers,no meaningful statistical difference was observed in the pooled RRs of both sexes,males and females,in China,other Asian countries,and all of Asia.Conclusion The RR of males ever smokers in China was smaller than that in other Asian countries due to the few articles of morbidity subgroup,but had no statistical difference with the whole of Asia;other groups of ever smokers,current smokers,and former smokers were not statistically significant with other Asian countries or the whole of Asia. 展开更多
关键词 active smoking STROKE China Asian countries META-ANALYSIS
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Active optical waveguides and metal ion sensors based on nanofibers with aggregation induced emission
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作者 Liping Xu Xianguang Yang +9 位作者 Ming Chen Kai Li Junda He Dehua Tian Zaizhu Lou Fangchang Tan Puxiang Lai Andrea Camposeo Dario Pisignano Baojun Li 《Nano Research》 2026年第1期1077-1088,共12页
Fiber-structured ion sensors have gained traction in health monitoring and medical diagnostics owing to their structural flexibility,enhanced sensitivity,and suitability for integration into wearable devices.This stud... Fiber-structured ion sensors have gained traction in health monitoring and medical diagnostics owing to their structural flexibility,enhanced sensitivity,and suitability for integration into wearable devices.This study employed a simple and efficient solutionbased process to fabricate nanofibers containing aggregation-induced emission(AIE)dyes.The resulting AIE nanofibers exhibited stable and intense fluorescence,nanosecond fluorescence lifetime,and low-loss light transport when functioning as active waveguides.Additionally,crossed nanofiber intersections exhibited diffraction-limited emission spots.The AIE nanofibers demonstrate efficient and ionspecific fluorescence quenching in response to Ag^(+).These results support the development of sensing units capable of operating in liquid environments or in direct contact with skin or tissues,facilitating real-time monitoring of ion concentrations for personalized healthcare management. 展开更多
关键词 aggregation-induced emission NANOFIBERS fluorescence lifetime active waveguide ion sensors
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A review of the pharmacology of active ingredients in Ginseng Radix et Rhizoma(Renshen)anti-aging
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作者 Tian-Yuan Liu Jin-Ning Chang +6 位作者 Xiao-Wei Dai Hao-Xin Ma Wei-Jia Chen Rui Du Akmal Muhammad Jian-Ming Li Zhong-Mei He 《Traditional Medicine Research》 2026年第3期65-76,共12页
Population aging is one of the common challenges in the current world.As people age,the body’s tissues including cells,and molecules inevitably degrade,and their functions gradually decline,causing various age-relate... Population aging is one of the common challenges in the current world.As people age,the body’s tissues including cells,and molecules inevitably degrade,and their functions gradually decline,causing various age-related diseases like Alzheimer’s disease,osteoporosis,low immunity,glucose and lipid metabolism disorders,and cardiovascular diseases.With the continuous increase of the elderly population,the pressure on the medical industry is increasing.To lower the burden on the medical industry and increase the average age of the elderly,it is vital to explore effective anti-aging materials.Ginseng Radix et Rhizoma(Renshen),as a traditional and precious Chinese medicinal herb,is known as the“king of all herbs”.It is famous for its effects of“tonifying Qi,restoring pulse”(helping with the generation of Qi(the fundamental,vital energy that continuously flows within the body)and the circulation of blood)and strengthening the body,nourishing the spleen and lungs,generating fluids and nourishing blood,calming the mind and improving intelligence.Recently,its anti-aging effect has received increasing attention from modern scientific research.This study summarizes the pharmacological effects of the main active ingredients of Renshen(ginsenosides,polysaccharides,etc.)on resisting aging,including preventing neuroaging,suppressing skin aging,mitigating ovarian aging,inhibiting osteoporosis and arthritis,enhancing the immune system of the elderly,protecting the cardiovascular system,resisting aging-induced fatigue and exerting the anti-tumor effects.Through network pharmacology and molecular docking,the anti-aging active ingredients of Renshen were screened,and the key targets and pathways of anti-aging active ingredients in Renshen were determined.Using network pharmacology,totally 106 drug targets and 3,479 disease targets were screened,and 79 common targets between aging and Renshen were identified.Three core targets were identified in the PPI network,including TNF,AKT1,and IL-1β.Molecular docking was used to obtain further verification.This study emphasizes the potential of Renshen as a source of anti-aging activity,which can be developed into a novel drug for the treatment of age-related diseases. 展开更多
关键词 Renshen active ingredients ANTI-AGING pharmacological effects network pharmacology molecular docking
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Early intelligent active assistance in walking for hemiplegic patients under suspension protection: a randomized controlled trial
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作者 Ma Shanxin Zheng Jianling +5 位作者 Cheng Jian Lin Xi Li Qiuyuan Wang Li Zeng Yangkang Song Luping 《中国组织工程研究》 北大核心 2026年第12期3075-3082,共8页
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec... BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function. 展开更多
关键词 hemiplegia stroke suspension protection system personal assistant machine intelligent walking aid early rehabilitation active training walking function NEUROPLASTICITY gait analysis motor function recovery rehabilitation training balance ability
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Regulation mechanism of active magnesium oxide on precipitation of lanthanum hydroxide 被引量:1
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作者 Jianwei Zhao Haiqing Hao +4 位作者 Yanyan Zhao Meng Wang Xu Sun Zongyu Feng Xiaowei Huang 《Journal of Rare Earths》 2025年第6期1264-1271,I0007,共9页
Precipitation is often used for the preparation of La(OH)_(3)with precipitants of liquid alkali and ammonia.To solve the problems of high cost and wastewater pollution caused by common precipitants,the active MgO synt... Precipitation is often used for the preparation of La(OH)_(3)with precipitants of liquid alkali and ammonia.To solve the problems of high cost and wastewater pollution caused by common precipitants,the active MgO synthesized by pyrolysis was used as the precipitant to prepare La(OH)_(3).The species distribution of LaCl_(3)and LaCl_(3)-MgCl_(2)mixed system solution was calculated,and the kinetic analysis of the precipi-tation process was carried out to confirm the key factors influencing the precipitation of La(OH)_(3).The results show that La(OH)_(3)with D_(50)of 5.57μm,a specific surface area of 25.70 m^(2)/g,a rod-like shape,and MgO content of 0.044 wt%,was successfully prepared by adding active MgO.The precipitation ratio of La reaches 99.92%.The La(OH)_(3)precipitation is controlled by the diffusion process.The activity of MgO has a significant influence on MgO content in the precipitate.The preparation of La(OH)_(3)by active MgO provides a potential way for an eco-friendly preparation method of rare earth. 展开更多
关键词 active magnesium oxide PRECIPITATION Lanthanum hydroxide REGULATION Rare earths
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Advances and mechanisms of traditional Chinese medicine and its active ingredients against antibiotic-resistant Escherichia coli infections 被引量:1
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作者 Shuo Yang Ping Su +2 位作者 Lu Li Shuang Liu Yi Wang 《Journal of Pharmaceutical Analysis》 2025年第2期375-388,共14页
In clinical practice,antibiotics have historically been utilized for the treatment of pathogenic bacteria.However,the gradual emergence of antibiotic resistance among bacterial strains has posed a significant challeng... In clinical practice,antibiotics have historically been utilized for the treatment of pathogenic bacteria.However,the gradual emergence of antibiotic resistance among bacterial strains has posed a significant challenge to this approach.In 2022,Escherichia coli,a Gram-negative bacterium renowned for its widespread pathogenicity and high virulence,emerged as the predominant pathogenic bacterium in China.The rapid emergence of antibiotic-resistant E.coli strains has rendered antibiotics insufficient to fight E.coli infections.Traditional Chinese medicine(TCM)has made remarkable contributions to the health of Chinese people for thousands of years,and its significant therapeutic effects have been proven in clinical practice.In this paper,we provide a comprehensive review of the advances and mechanisms of TCM and its active ingredients against antibiotic-resistant E.coli infections.First of all,this review introduces the classification,antibiotic resistance characteristics and mechanisms of E.coli.Then,the TCM formulas and extracts are listed along with their active ingredients against E.coli,including extraction solution,minimum inhibitory concentration(MIC),and the antibacterial mechanisms.In addition,there is growing evidence supporting the synergistic therapeutic strategy of combining TCM with antibiotics for the treatment of antibiotic-resistant E.coli infections,and we provide a summary of this evidence and its underlying mechanisms.In conclusion,we present a comprehensive review of TCM and highlight its potential and advantages in the prevention and treatment of E.coli infections.We hold the opinion that TCM will play an important role in global health,pharmaceutical development,and livestock farming in the future. 展开更多
关键词 Escherichia coli ANTIBIOTIC-RESISTANCE Traditional Chinese medicine active ingredients Antibacterial mechanism
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Regulation Active Sites of Porous GaN Crystal Via Mn_(3)O_(4)Nanosheets for Advanced High Temperature Energy Storage 被引量:1
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作者 Songyang Lv Shouzhi Wang +7 位作者 Qirui Zhang Lin Xu Ge Tian Jiaoxian Yu Guodong Wang Lili Li Xiangang Xu Lei Zhang 《Energy & Environmental Materials》 2025年第3期112-121,共10页
Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and in... Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and inadequate energy densities are bottlenecks to its practical application.Herein,the self-supported GaN/Mn_(3)O_(4) integrated electrode is developed for both energy harvesting and storage under the high temperature environment.The experimental and theoretical calculations results reveal that such integrated structures with Mn-N heterointerface bring abundant active sites and reconstruct low-energy barrier channels for efficient charge transferring,reasonably optimizing the ions adsorption ability and strengthening the structural stability.Consequently,the assembled GaN based supercapacitors deliver the power density of 34.0 mW cm^(-2) with capacitance retention of 81.3%after 10000 cycles at 130℃.This work innovatively correlates the centimeter scale GaN single crystal with ideal theoretical capacity Mn_(3)O_(4) and provides an effective avenue for the follow-up energy storage applications of the wide bandgap semiconductor. 展开更多
关键词 active sites density functional theory gallium nitride crystal high temperature SUPERCAPACITORS
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Output feedback active disturbance rejection control of an electro-hydraulic servo system based on command filter 被引量:1
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作者 Yanchun BAI Jianyong YAO +1 位作者 Jian HU Guangbin FENG 《Chinese Journal of Aeronautics》 2025年第2期214-225,共12页
The output feedback active disturbance rejection control of a valve-controlled cylinder electro-hydraulic servo system is investigated in this paper.First,a comprehensive nonlinear mathematical model that encompasses ... The output feedback active disturbance rejection control of a valve-controlled cylinder electro-hydraulic servo system is investigated in this paper.First,a comprehensive nonlinear mathematical model that encompasses both matched and mismatched disturbances is formulated.Due to the fact that only position information can be measured,a linear Extended State Observer(ESO)is introduced to estimate unknown states and matched disturbances,while a dedicated disturbance observer is constructed to estimate mismatched disturbances.Different from the traditional observer results,the design of the disturbance observer used in this study is carried out under the constraint of output feedback.Furthermore,an output feedback nonlinear controller is proposed leveraging the aforementioned observers to achieve accurate trajectory tracking.To mitigate the inherent differential explosion problem of the traditional backstepping framework,a finite-time stable command filter is incorporated.Simultaneously,considering transient filtering errors,a set of error compensation signals are designed to counter their negative impact effectively.Theoretical analysis affirms that the proposed control strategy ensures the boundedness of all signals within the closed-loop system.Additionally,under the specific condition of only time-invariant disturbances in the system,the conclusion of asymptotic stability is established.Finally,the algorithm’s efficacy is validated through comparative experiments. 展开更多
关键词 active disturbance rejection CONTROL Extended state observer Output feedback Disturbance observer Command filter
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A PCM-based active temperature-preserved coring method for deep sea natural gas hydrate 被引量:1
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作者 Han Wu Yunqi Hu +4 位作者 Chenghang Fu Ling Chen Zhiqiang He Meng Xu Heping Xie 《International Journal of Mining Science and Technology》 2025年第11期1939-1954,共16页
Natural gas hydrate(NGH)has a bright future as a clean energy source with huge reserves.Coring is one of the most direct methods for NGH exploration and research.Preserving the in-situ properties of the core as much a... Natural gas hydrate(NGH)has a bright future as a clean energy source with huge reserves.Coring is one of the most direct methods for NGH exploration and research.Preserving the in-situ properties of the core as much as possible during the coring process is crucial for the assessment of NGH resources.However,most existing NGH coring techniques cannot preserve the in-situ temperature of NGH,leading to distortion of the physical properties of the obtained core,which makes it difficult to effectively guide NGH exploration and development.To overcome this limitation,this study introduces an innovative active temperature-preserved coring method for NGH utilizing phase change materials(PCM).An active temperature-preserved corer(ATPC)is designed and developed,and an indoor experimental system is established to investigate the heat transfer during the coring process.Based on the experimental results under different environment temperatures,a heat transfer model for the entire ATPC coring process has been established.The indoor experimental results are consistent with the theoretical predictions of the heat transfer model,confirming its validity.This model has reconstructed the temperature changes of the NGH core during the coring process,demonstrating that compared to the traditional coring method with only passive temperature-preserved measures,ATPC can effectively reduce the core temperature by more than 5.25℃.With ATPC,at environment temperatures of 15,20,25,and 30℃,the duration of low-temperature state for the NGH core is 53.85,32.87,20.32,and 11.83 min,respectively.These findings provide new perspectives on temperature-preserving core sampling in NGH and provide technical support for exploration and development in NGH. 展开更多
关键词 Deep sea coring Natural gas hydrate active temperature-preserved method Phase change material
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Overview on active disturbance rejection control for electro-mechanical actuation servo drive 被引量:1
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作者 Chunqiang LIU Guangzhao LUO +1 位作者 Zhe CHEN Xiaofeng DING 《Chinese Journal of Aeronautics》 2025年第7期291-309,共19页
Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical... Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical arms.The performance of the servo drive,which encompasses the response to the torque,efficiency,control bandwidth and the steady-state positioning accuracy,significantly influences the performance of the aviation actuation.Consequently,enhancing the control bandwidth and refining the positioning accuracy of aviation electro-mechanical actuation servo drives have emerged as a focal point of research.This paper investigates the multi-source disturbances present in aviation electro-mechanical actuation servo systems and summarizes recent research on high-performance servo control methods based on active disturbance rejection control(ADRC).We present a comprehensive overview of the research status pertaining to servo control architecture,strategies for suppressing disturbances in the current loop,and ADRC-based strategies for the position loop.We delineate the research challenges and difficulties encountered by aviation electro-mechanical actuation servo drive control technology. 展开更多
关键词 active disturbance rejection control Electric servo drive Permanent magnet synchronous motor Electro-mechanical actuation
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Reactive Power Optimization Model of Active Distribution Network with New Energy and Electric Vehicles 被引量:1
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作者 Chenxu Wang Jing Bian Rui Yuan 《Energy Engineering》 2025年第3期985-1003,共19页
Considering the uncertainty of grid connection of electric vehicle charging stations and the uncertainty of new energy and residential electricity load,a spatio-temporal decoupling strategy of dynamic reactive power o... Considering the uncertainty of grid connection of electric vehicle charging stations and the uncertainty of new energy and residential electricity load,a spatio-temporal decoupling strategy of dynamic reactive power optimization based on clustering-local relaxation-correction is proposed.Firstly,the k-medoids clustering algorithm is used to divide the reduced power scene into periods.Then,the discrete variables and continuous variables are optimized in the same period of time.Finally,the number of input groups of parallel capacitor banks(CB)in multiple periods is fixed,and then the secondary static reactive power optimization correction is carried out by using the continuous reactive power output device based on the static reactive power compensation device(SVC),the new energy grid-connected inverter,and the electric vehicle charging station.According to the characteristics of the model,a hybrid optimization algorithm with a cross-feedback mechanism is used to solve different types of variables,and an improved artificial hummingbird algorithm based on tent chaotic mapping and adaptive mutation is proposed to improve the solution efficiency.The simulation results show that the proposed decoupling strategy can obtain satisfactory optimization resultswhile strictly guaranteeing the dynamic constraints of discrete variables,and the hybrid algorithm can effectively solve the mixed integer nonlinear optimization problem. 展开更多
关键词 active distribution network new energy electric vehicles dynamic reactive power optimization kmedoids clustering hybrid optimization algorithm
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Vibration reduction mechanism and characteristics evaluation of active elastic support/dry friction damper 被引量:1
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作者 Siji WANG Dafang LIN +2 位作者 Quankun LI Jiayao CHEN Yuan LIU 《Chinese Journal of Aeronautics》 2025年第4期333-348,共16页
This paper studies the coupling mechanism between the nonlinear stiffness and damping coefficients of Active Elastic Support/Dry Friction Damper(AESDFD)and rotor system.First,parameters for evaluating the vibration re... This paper studies the coupling mechanism between the nonlinear stiffness and damping coefficients of Active Elastic Support/Dry Friction Damper(AESDFD)and rotor system.First,parameters for evaluating the vibration reduction characteristics are proposed to facilitate the design of the AESDFD.To achieve this,the nonlinear friction force is initially represented as equivalent stiffness and damping coefficients,based on the ball-plate friction model.Second,three evaluation parameters—optimal slipping displacement,loss factor,and controllability—are proposed to reveal the vibration reduction characteristics of the AESDFD,alongside determining the optimal normal force.Subsequently,the finite element method,in conjunction with the ball-plate friction model,is introduced to formulate the governing equation of a low-pressure rotor system equipped with AESDFDs.The steady-state responses of the AESDFDs-rotor system are solved using the harmonic balance method combined with an efficient iteration method.Finally,the solutions are validated on the AESDFDs-rotor system both numerically and experimentally.The results indicate that controllability effectively assesses the vibration reduction performance of the AESDFD and is relatively insensitive to variations in low normal force.Away from the critical speed,the AESDFD suppresses vibration by altering the resonance position of the rotor system through its stiffness coefficient.Near the critical speed,vibration reduction is achieved primarily through energy dissipation by the damping coefficient.If the loss factor is less than one,the stiffness coefficient can diminish the vibration reduction effect of the damping coefficient.Notably,the optimal normal force of the AESDFD achieves optimal vibration reduction effect.This study reveals that changes in rotor system unbalance do not affect the vibration reduction characteristics of the AESDFD,with the same upper limit to the vibration reduction effect of the AESDFD. 展开更多
关键词 active dry friction damper Low-pressure rotor system Vibration analysis Stiffness and damping coefficients Evaluation parameters Finite element method
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Active sites and impact of preparation pH on the Cu/ZnO/ZrO_(2) catalysts for methanol production via CO_(2) hydrogenation
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作者 MENG Xinyue SUN Shangcong +1 位作者 CAO Shuo PENG Bo 《燃料化学学报(中英文)》 北大核心 2025年第11期1569-1582,共14页
Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active... Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active centers influencing the rate of both methanol and CO formation.The particle size and the interaction between Cu and the support materials are influenced by the coprecipitation conditions,let alone that the mechanistic divergence remains unclear.In this work,a series of Cu/ZnO/ZrO_(2) catalysts were prepared via co-precipitation at different pH value and systematically characterized.The structure has been correlated with kinetic results to establish the structure-performance relationship.Kinetic analysis demonstrates that methanol synthesis follows a single-site Langmuir-Hinshelwood(L-H)mechanism,i.e.,Cu serves as the active site where CO_(2) and H_(2) competitively adsorb and react to form methanol.In contrast,CO formation proceeds via a dual-site L-H mechanism,where CO_(2) adsorbs onto ZnO and H_(2) onto Cu,with the reaction occurring at the Cu/ZnO interface.Therefore,for the direct formation of methanol,solely reducing the particle size of Cu would not be beneficial. 展开更多
关键词 CO_(2)hydrogenation methanol synthesis active sites KINETICS
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Methods for the formation of M-N_(x)-C active sites on single-atom catalysts and their role in persulfate activation by non-radical paths
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作者 SI Wen-hao SI Jin-xuan +4 位作者 WANG Kang-jun QI Fei CHEN Jia-bin ZENG Ze-quan HUANG Zhang-gen 《新型炭材料(中英文)》 北大核心 2025年第5期993-1015,共23页
In recent years,numer-ous single-atom catalysts(SACs)have been synthesized to activate persulfate(PS)by a non-radical pathway because of its high se-lectivity,and activity for the cata-lyst.Metal-nitrogen-carbon(M-N_(... In recent years,numer-ous single-atom catalysts(SACs)have been synthesized to activate persulfate(PS)by a non-radical pathway because of its high se-lectivity,and activity for the cata-lyst.Metal-nitrogen-carbon(M-N_(x)-C)has been identified as the key active site in SACs.Although methods for preparing SACs have been extensively reported,a systematic summary of the direct construction of M-N_(x)-C,espe-cially unconventional metal-nitrogen-carbon(UM-N_(x)-C,x≠4),on SACs for PS non-radical activation has still not been reported.The role of the M-N_(x)-C active sites on PS non-radical activation is discussed and methods for the formation of M-N_(x)-C and UM-N_(x)-C active sites in SACs and the effect of catalyst carriers such as carbon nitride(g-C_(3)N_(4)),MOFs,COFs,and other car-bon materials are reviewed.Direct and indirect methods,especially for UM-N_(x)-C active site formation,are also elaborated.Factors affecting the formation of a M-N_(x)-C active site on SACs are also discussed.Prospects for the use of M-N_(x)-C active sites for the non-radical activation of PS by SACs to remove organic contaminants from wastewater are evaluated. 展开更多
关键词 Single-atom catalysts PERSULFATE Non-radical pathway Unconventional metal-nitrogen-carbon active site Organic contaminants
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Pressure in active matter
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作者 Guo Yu Ruiyao Li +5 位作者 Fukang Li Jiayu Zhang Xiyue Li Zequ Chen Joscha Mecke Yongxiang Gao 《Chinese Physics B》 2025年第9期330-342,共13页
In the last decade,the study of pressure in active matter has attracted growing attention due to its fundamental relevance to nonequilibrium statistical physics.Active matter systems are composed of particles that con... In the last decade,the study of pressure in active matter has attracted growing attention due to its fundamental relevance to nonequilibrium statistical physics.Active matter systems are composed of particles that consume energy to sustain persistent motion,which are inherently far from equilibrium.These particles can exhibit complex behaviors,including motility-induced phase separation,clustering,and anomalous stress distributions,motivating the introduction of active swim stress and swim pressure.Unlike in passive fluids,pressure in active systems emerges from momentum flux originating from swim force rather than equilibrium conservative interactions,offering a distinct perspective for understanding their mechanical response.Simple models of active Brownian particles(ABPs)have been employed in theoretical and simulation studies across both dilute and dense regimes,revealing that pressure is a state function and exhibits a nontrivial dependence on density.Together with nonequilibrium statistical concepts such as effective temperature and effective adhesion,pressure offers important insight for understanding behaviors in active matter such as sedimentation equilibrium and motility induced phase separation.Extensions of ABP models beyond their simplest form have underscored the fragility of the pressure-based equation of state,which can break down under factors such as density-dependent velocity,torque,complex boundary geometries and interactions.Building on these developments,this review provides a comprehensive survey of theoretical and experimental advances,with particular emphasis on the microscopic origins of active pressure and the mechanisms underlying the breakdown of the equation of state. 展开更多
关键词 active matter active pressure equation of state active Brownian particles
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Mechanisms of Targeted Drug Delivery for Liver Cancer: Active, Passive, and Subcellular Strategies
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作者 Yang Tian Yusheng Shi 《Journal of Biosciences and Medicines》 2025年第2期369-384,共16页
This article provides a comprehensive review of various approaches to targeted drug delivery for liver cancer, an area of significant need due to the limited effectiveness of current treatments. The article begins by ... This article provides a comprehensive review of various approaches to targeted drug delivery for liver cancer, an area of significant need due to the limited effectiveness of current treatments. The article begins by highlighting the role of the liver in metabolism and discusses the high mortality associated with hepatocellular carcinoma (HCC). The shortcomings of traditional chemotherapy, such as multidrug resistance and off-target effects, necessitate the exploration of novel therapeutic strategies, with a focus on targeted approaches. The review details both passive and active targeting strategies. Passive targeting leverages the enhanced permeability and retention (EPR) effect and unique features of the tumor microenvironment, while active targeting employs specific ligands, such as peptides, antibodies, and proteins, to bind to overexpressed receptors on liver and tumor cells. The article further details many examples of active targeting using the asialoglycoprotein receptor (ASGPR), glycyrrhetinic acid (GA), transferrin receptor (TfR), and folate receptor (FR) on hepatocytes and tumor cells, demonstrating that there has been significant research effort put into this field. The importance of non-parenchymal cells in the liver is also discussed, and the article examines methods of targeting Kupffer cells, sinusoidal endothelial cells, and hepatic stellate cells for therapeutic benefit. The review goes on to cover the emerging field of subcellular targeting, including specific strategies to target the nucleus, mitochondria, and the endoplasmic reticulum/Golgi apparatus, noting that although there has been some progress, further research is needed in this area. The text finishes with a summary which acknowledges that while targeted therapies, including enzyme-activated prodrugs, such as Pradefovir, and other novel methods for drug delivery have shown significant promise, challenges remain in translating these therapies into clinical use due to limitations in understanding the sequential transport and the mechanisms of action. Ultimately, the article emphasizes the need for in-depth research to fully realize the potential of precision cancer therapies for liver cancer. 展开更多
关键词 Targeted Drug Delivery Hepatocellular Carcinoma (HCC) active Targeting Subcellular Targeting NANOMEDICINE
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Super-high Active,Homogeneous Vanadium(Ⅴ)Complexes Bearing Bidentate Phenoxy-Phosphine Ligands for Diverse Olefins(Co)polymerization
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作者 Biao Li Yuan-Bo Liu +2 位作者 Ying-Li Ding Li Pan Yue-Sheng Li 《Chinese Journal of Polymer Science》 2025年第12期2299-2309,I0011,共12页
A series of imido-vanadium(Ⅴ)complexes bearing bidentate phenoxy-phosphine ligands were synthesized and characterized by NMR,elemental analysis,and single-crystal X-ray diffraction.These complexes demonstrated excell... A series of imido-vanadium(Ⅴ)complexes bearing bidentate phenoxy-phosphine ligands were synthesized and characterized by NMR,elemental analysis,and single-crystal X-ray diffraction.These complexes demonstrated excellent catalytic performance in ethylene/1-hexene copolymerization,achieving high activities of 12.0×10~6–49.0×10~6 g_(polymer)·(mol_(V))^(-1)·h^(-1)and affording random copolymers with tunable 1-hexene incorporations.These catalysts also exhibited ultrahigh activity,up to 112.2×10~6 g_(polymer)·(mol_(V))^(-1)·h^(-1),in ethylene/norbornene(NB)copolymerization,yielding cyclic olefin copolymers with adjustable NB incorporations.Remarkably,these catalysts demonstrated exceptional tolerance toward polar functional groups,enabling efficient copolymerization of ethylene with both 10-undecen-1-ol(U-OH)and 5-norbornene-2-methanol(NB-OH),incorporating about 2 mol%polar comonomers with high efficiency.Different with the catalytic behaviors in copolymerization of ethylene with nonpolar comonomers,the catalytic activities in E/U-OH copolymerization(25.7×10~6 g_(polymer)·(mol_(V))^(-1)·h^(-1))were much higher than those in E/NB-OH copolymerization(8.6×10^(6) g_(polymer)·(mol_(V))^(-1)·h^(-1)).DFT calculations revealed that the catalytic performance is governed by synergistic electronic and steric effects.For E/NB copolymerization,strong preference for cyclic olefins was attributed to favorable transition state stabilization.In polar comonomer systems,steric effects were predominant,with NB-OH exhibiting a larger buried volume around vanadium center upon coordination compared to U-OH.Overall,this work provides fundamental insights into vanadium-catalyzed(co)polymerization and offers new strategies for tailored polyolefin design. 展开更多
关键词 Vanadium catalysts COPOLYMERIZATION Polar polyolefin Ultrahigh activity activity inversion
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Pacing,conventional physical activity and active video gaming to increase physical activity levels for adults with myalgic encephalomyelitis/chronic fatigue syndrome:a pilot feasibility study
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作者 Brett Tarca Kade Davison +3 位作者 Ashleigh E.Smith Alexandra Wade Katie I.Trenorden Katia E.Ferrar 《Translational Exercise Biomedicine》 2025年第3期216-230,共15页
Objectives:People living with myalgic encephalomyelitis/chronic fatigue syndrome(ME/CFS)may face unique barriers to physical activity.Active video games may overcome these barriers and increase physical activity.The p... Objectives:People living with myalgic encephalomyelitis/chronic fatigue syndrome(ME/CFS)may face unique barriers to physical activity.Active video games may overcome these barriers and increase physical activity.The primary aim of this pilot study was to determine the feasibility and acceptability of active video games to increase physical activity levels of people with ME/CFS.Methods:A mixed method design was employed.Adults living with ME/CFS were randomised to a six-month intervention of(1)pacing,(2)pacing and conventional physical activity,or(3)pacing and active video gaming.Feasibility and acceptability were determined through semi-structured interviews.Health-related outcomes(e.g.,physical activity,blood samples,quality of life,and functioning)were also collected.Results:Fifteen people were assigned an intervention group with 12 completing.Three themes were identified from post-intervention interviews(1)positivity led to overall acceptability,(2)flexibility enabled participant autonomy,and(3)knowledge was gained about the self.No changes were seen in physical activity levels.An active video gaming intervention is acceptable but not feasible for people living with ME/CFS.Conclusions:Taken together,results suggest that physical activity can be managed safely by some people living with ME/CFS.Trial registration ACTRN12616000285459. 展开更多
关键词 chronic fatigue syndrome EXERCISE physical activity active video gaming PACING
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A hydrogen-centric perspective on electrocatalytic nitrate reduction:Managing the active hydrogen lifecycle from generation to utilization
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作者 Zhihao Wang Xu Zhang +1 位作者 Zhiyu Ren Zhimin Chen 《Journal of Energy Chemistry》 2025年第10期210-230,共21页
Electrocatalytic nitrate reduction reaction(NitRR)utilizing water as a hydrogen source under ambient conditions represents a highly promising avenue for sustainable ammonia synthesis and environmental remediation.Howe... Electrocatalytic nitrate reduction reaction(NitRR)utilizing water as a hydrogen source under ambient conditions represents a highly promising avenue for sustainable ammonia synthesis and environmental remediation.However,achieving high efficiency and selectivity in NitRR is fundamentally challenged by the complex lifecycle management of active hydrogen derived from water splitting.This review provides a timely and comprehensive analysis centered on the pivotal role and meticulous regulation of active hydrogen throughout the NitRR process.We first elucidate the distinct functions and characteristics of various hydrogen species,followed by a survey of advanced characterization techniques crucial for monitoring the dynamics of active hydrogen.Critically,three core strategies were systematically dissected to modulate the active hydrogen lifecycle:accelerating water activation and dissociation,enhancing the directional transport of hydrogen species,and precisely tuning active hydrogen coupling pathways while suppressing parasitic hydrogen evolution.By consolidating current understanding from both catalyst design and reaction mechanism perspectives,this review offers a hydrogen-centric roadmap and highlights emerging opportunities for rationally engineering advanced NitRR systems. 展开更多
关键词 Electrocatalytic nitrate reduction active hydrogen regulation Characterization methods Water activation and dissociation Promoting active hydrogen transfer Hydrogen evolution suppression
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