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How delaying post-silking senescence in lower leaves of maize plants increases carbon and nitrogen accumulation and grain yield 被引量:4
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作者 Rongfa Li Dandan Hu +5 位作者 Hao Ren Qinglong Yang Shuting Dong Jiwang Zhang Bin Zhao Peng Liu 《The Crop Journal》 SCIE CSCD 2022年第3期853-863,共11页
Planting maize at high densities leads to early leaf senescence,and the resulting reduction in the number of lower leaves affects the plant’s root function and lowers its grain yield.However,the nature of the process... Planting maize at high densities leads to early leaf senescence,and the resulting reduction in the number of lower leaves affects the plant’s root function and lowers its grain yield.However,the nature of the process by which lower leaf senescence affects biomass accumulation and grain yield formation in maize is not clear.This study aimed to shed light on how these factors are related by investigating the effects of the plant growth regulator 6-benzyladenine(6-BA)on the senescence of lower leaves of maize plants.In two maize cultivars planted at densities of 67,500(low density,LD)and 90,000(high density,HD)plants ha^(-1),plants treated with 6-BA maintained a high green leaf area index(LAI)longer than control(CK)plants,enabling them to maintain a higher photosynthetic rate for a longer period of time and produce more biomass before reaching physiological maturity.Spraying the lower leaves of maize plants with a 6-BA solution increased the distribution of;C-photosynthates to their roots,lower leaves and bracts,a result that can be ascribed to a decreased retention of;C-photosynthates in the stem and grain.In both seasons of the experiment,maize plants treated with 6-BA accumulated more N in grain and maintained a higher N content in roots and leaves,especially in lower leaves,than CK.Increased C assimilation in the lower leaves may explain why N uptake in plants subjected to the 6-BA treatment exceeded that in CK plants and why both photosynthesis rate and dry matter accumulation were maintained throughout grain filling.Our results suggest that a suitable distribution of C and N in leaves post-silking may maintain plant root function,increase N use efficiency,maximize the duration of high LAI,and increase grain yield. 展开更多
关键词 13C-Photosynthate distribution Nitrogen uptake Maize grain yield delaying lower leaf senescence Post-silking
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PROGRESS AND PERSPECTIVE OF ACUPUNCTURE AND MOXIBUSTION IN DELAYING SENILITY
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作者 黄诚 陈汉平 《World Journal of Acupuncture-Moxibustion》 1995年第3期42-50,共9页
In this paper, we reviewed the developing history of delaying senility of acupunctureand moxibustion, summarized 41 reports about the effects of acupuncture and moxibustion on elderly,normal subject and the "defi... In this paper, we reviewed the developing history of delaying senility of acupunctureand moxibustion, summarized 41 reports about the effects of acupuncture and moxibustion on elderly,normal subject and the "deficiency syndrome" model animal, and expounded the rnechanisms in the aspects of immunology, endocrinology and biology. In addition, we also discussed the influence fac-tors and the developing trends of delaying senility of acupuncture and moxibustion in corning years. 展开更多
关键词 ACUPUNCTURE MOXIBUSTION delaying senility AGING
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CLINICAL OBSERVATION OF THE EFFECT OF HEALTH-PRESERVING MOXIBUSTION ON DELAYING AGING
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作者 王玲玲 吴中朝 +1 位作者 徐兰凤 邱茂良 《World Journal of Acupuncture-Moxibustion》 1996年第3期25-30,共6页
The present paper reports a clinical observation of the effect of health-preservingmoxibustion in the aged people without apparent organic diseases. Results show that the health-preserving moxibustion has an evident a... The present paper reports a clinical observation of the effect of health-preservingmoxibustion in the aged people without apparent organic diseases. Results show that the health-preserving moxibustion has an evident action in lessening aging symptoms and improving physio-logic functions of the senile body. It is held in traditional Chinese medicine that from the middle-aged period on, the decline of kidney Qi is an important cause of senility and deficiency of thespleen and blood stasis also play a role in some degree. Health-preserving moxibustion ofShenque and Zusanli has actions in warming Yang, reinforcing Qi and promoting blood circulationto remove obstruction in meridians. It is thus a method for self health protection. 展开更多
关键词 Senility/delaying AGING MOXIBUSTION THERAPY
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Earthquake triggering and delaying caused by fault interaction on Xianshuihe fault belt, southwestern China
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作者 张秋文 张培震 +2 位作者 王乘 汪一鹏 Michael A Ellis 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第2期156-165,共10页
The coseismic Coulomb stress change caused by fault interaction and its influences on the triggering and delaying of earthquake are briefly discussed. The Xianshuihe fault belt consists of Luhuo, Daofu, Kangding, Qian... The coseismic Coulomb stress change caused by fault interaction and its influences on the triggering and delaying of earthquake are briefly discussed. The Xianshuihe fault belt consists of Luhuo, Daofu, Kangding, Qianning and Ganzi fault. Luohuo (MS=7.6, 1973)-Kangding (MS=6.2, 1975)-Daofu (MS=6.9, 1981)-Ganzi (MS=6.0, 1982) earthquake is a seismic sequence continuous on the time axis with magnitude greater than 6.0. They occurred on the Luhuo, Kangding, Daofu and Ganzi fault, respectively. The coseismic Coulomb stress changes caused by each earthquake on its surrounding major faults and microcracks are calculated, and their effects on the triggering and delaying of the next earthquake and aftershocks are analyzed. It is shown that each earthquake of the sequence occurred on the fault segment with coseismic Coulomb stress increases caused by its predecessors, and most after-shocks are distributed along the microcracks with relatively larger coseismic Coulomb stress increases resulted from the main shock. With the fault interaction considered, the seismic potential of each segment along Xianshuihe fault belt is reassessed, and contrasted with those predicted results ignoring coseismic Coulomb stress change, the significance of fault interaction and its effect on triggering and delaying of earthquake are emphasized. It is con-cluded that fault interaction plays a very important role on seismic potential of Xianshuihe fault belt, and the maximal change of future earthquake probability on fault segment is up to 30.5%. 展开更多
关键词 coseismic Coulomb stress change fault interaction earthquake triggering and delaying seismic potential assessment Xianshuihe fault belt
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Experimental Method Of Cosmetics Human Efficacy Evaluation-Delaying Skin Aging Efficacy
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作者 Wang Peng Zhang Hongyan +3 位作者 Sha Ou Guo Ruoxi Zhang Han Zhang Lei 《China Detergent & Cosmetics》 2021年第4期66-69,共4页
This paper briefly introduce the test method for human evaluation of cosmetics to delay skin aging,and provide reference for the test of relevant indexes.By formulating a reasonable test plan and choosing appropriate ... This paper briefly introduce the test method for human evaluation of cosmetics to delay skin aging,and provide reference for the test of relevant indexes.By formulating a reasonable test plan and choosing appropriate equipment to test the improvement of the skin aging characteristics before and after the product is used,it can provide a scientific basis for claiming the effect of delaying skin aging. 展开更多
关键词 delaying skin aging efficacy evaluation COSMETICS
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Research on the problem of delaying retiring age in China
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作者 Ge ZhiYong 《International English Education Research》 2015年第4期45-47,共3页
In recent years, China's aging population continues to accelerate the process, so that our aging population and the pension system is generated between the sustainable development of the serious contradictions, resul... In recent years, China's aging population continues to accelerate the process, so that our aging population and the pension system is generated between the sustainable development of the serious contradictions, resulting in a waste of human resources, increasing the operating pressure pensions, working hours inequity the negative impact on the existing retirement system challenges. Recently, the delay of the retirement age controversy sparked widespread concern in the community, the paper is as a starting point, a comprehensive analysis of the social contradictions of the current status of China's current retirement system, drawing on the successful adjustment of retirement abroad experience from multiple perspectives demonstrates the urgency of delayed retirement age and feasibility. This paper is divided into four chapters. The first chapter proposes the research background and significance of the age of retirement, as well as domestic and foreign scholars on the issue of research in the retirement age. The second chapter describes the status of China's retirement system, the contradiction between the implementation of the background, family problems and the current retirement age and the aging population about three aspects. The third chapter analyzes the feasibility to extend the retirement age. Chapter IV presents a delayed retirement policies and recommendations, with emphasis on "flexible retirement system." 展开更多
关键词 Aging population the retirement system delayed retirement age flexible retirement system
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Theoretical study on the thermally activated delayed fluorescence,and efficiency roll‑off characteristics of a series of blue and blue‑green Ir(Ⅲ)complexes
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作者 QIN Zhengkun BAO Lixin +4 位作者 ZHANG Yunkai CUI Lin WANG Jinyu WANG Yuhao SONG Mingxing 《无机化学学报》 北大核心 2026年第2期365-374,共10页
A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescenc... A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine. 展开更多
关键词 organic light‑emitting diodes Ir(Ⅲ)complex time‑dependent density functional theory thermal activation delayed fluorescence property efficiency roll‑off effect
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Indolizine-benzophenone hybrid acceptors enable TADF materials for bioimaging and photodynamic therapy in living cells
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作者 Hui Guo Wen-Wen Li +6 位作者 Mei-Yin Wu Jian-Bo Hu Jun Wang Yun Liu Yang Zou Chu-Luo Yang Kai-Lu Zheng 《Chinese Chemical Letters》 2026年第1期444-449,共6页
Thermally activated delayed fluorescence(TADF) emitters show great potential in photodynamic therapy(PDT) and bioimaging,leveraging their structural adaptability,efficient reverse intersystem crossing(RISC),robust pho... Thermally activated delayed fluorescence(TADF) emitters show great potential in photodynamic therapy(PDT) and bioimaging,leveraging their structural adaptability,efficient reverse intersystem crossing(RISC),robust photosensitizing capability,and high photoluminescence quantum yields(PLQYs).Herein,we developed a new class of donor-acceptor-donor(D-A-D)-type TADF materials by connecting the highly twisted indolizine-benzophenone electron acceptors with a series of electron donors including phenoxazine,phenothiazine and 9,9-dimethyl-9,10-dihydroacridine.These materials exhibit enhanced TADF properties,aggregation-induced emission(AIE),alongside high reactive oxygen species(ROS) generation efficiency,effectively mitigating aggregation-caused quenching observed in traditional fluorophores.Among them,IDP-p-PXZ,incorporating the phenoxazine donor,stands out with the smallest singlet-triplet splitting energy(ΔE_(ST)) and the highest spin-orbit coupling matrix elements(SOCMEs).Upon encapsulation into 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000](DSPE-PEG2000) nanoparticles(NPs),IDP-p-PXZ demonstrates extended delayed fluorescence lifetimes in air,an exceptionally fast intersystem crossing(ISC) rate constant(k_(ISC)) of 3.4×10^(7)s^(-1),and a radiative rate constant(k_(r)) of 5.05×10^(6)s^(-1).These NPs exhibit superior biocompatibility,efficient cellular internalization,and potent ROS production,enabling effective simultaneous PDT and confocal fluorescence imaging in HeLa cells. 展开更多
关键词 Indolizine-benzophenone Thermally activated delayed fluorescence Aggregation-induced emission Photodynamic therapy BIOIMAGING
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MWaOA:A Bio-Inspired Metaheuristic Algorithm for Resource Allocation in Internet of Things
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作者 Rekha Phadke Abdul Lateef Haroon Phulara Shaik +3 位作者 Dayanidhi Mohapatra Doaa Sami Khafaga Eman Abdullah Aldakheel N.Sathyanarayana 《Computers, Materials & Continua》 2026年第2期1285-1310,共26页
Recently,the Internet of Things(IoT)technology has been utilized in a wide range of services and applications which significantly transforms digital ecosystems through seamless interconnectivity between various smart ... Recently,the Internet of Things(IoT)technology has been utilized in a wide range of services and applications which significantly transforms digital ecosystems through seamless interconnectivity between various smart devices.Furthermore,the IoT plays a key role in multiple domains,including industrial automation,smart homes,and intelligent transportation systems.However,an increasing number of connected devices presents significant challenges related to efficient resource allocation and system responsiveness.To address these issue,this research proposes a Modified Walrus Optimization Algorithm(MWaOA)for effective resource management in smart IoT systems.In the proposed MWaOA,a crowding process is incorporated to maintain diversity and avoid premature convergence thereby enhancing the global search capability.During resource allocation,the MWaOA prevents early convergence,which aids in achieving a better balance between the exploration and exploitation phases during optimization.Empirical evaluations show that the MWaOA reduces energy consumption by approximately 4% to 34%and minimizes the response time by 6% to 33% across different service arrival rates.Compared to traditional optimization algorithms,MWaOA reduces energy consumption by 5% to 30%and minimizes the response time by 4% to 28% across different simulation epochs.The proposed MWaOA provides adaptive and robust resource allocation,thereby minimizing transmission cost while considering network constraints and real-time performance parameters. 展开更多
关键词 Delay GATEWAY internet of things resource allocation resource management walrus optimization algorithm
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Neural network control for mitigating actuator delay in ATR engines using predictive compensation and stability reward
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作者 Weidong CAI Wei ZHAO +3 位作者 Xiaorong XIANG Sanqun REN Xuesen YANG Qingjun ZHAO 《Chinese Journal of Aeronautics》 2026年第2期301-327,共27页
The flight envelope of Air Turbo Rocket(ATR)engines is broader compared to conventional aero-engines,and designing a full-envelope controller using traditional methods poses significant challenges due to a burdensome ... The flight envelope of Air Turbo Rocket(ATR)engines is broader compared to conventional aero-engines,and designing a full-envelope controller using traditional methods poses significant challenges due to a burdensome design process.To address this issue,this paper proposes a self-learning neural network controller design method based on Reinforcement Learning(RL).Additionally,a method for predictive compensation and stability rewards is proposed to reduce the system oscillation caused by actuator delay.This approach simplifies the actuator to a firstorder inertial element exhibiting pure delay.A simulation environment for the ATR engineactuator system is first established.Based on this environment,a self-learning neural network controller using a predictive compensator and the Proximal Policy Optimization(PPO)algorithm is then developed.Furthermore,the temporal difference signals from the controller output are integrated into the reward function to enhance system stability.The proposed method is validated through numerical simulations and semi-physical experiments.The numerical simulation results demonstrate that the proposed method increases the system's tolerance to delays from 20 ms to 400 ms.Under an actuator delay of 400 ms,the average steady-state error remains less than0.1%,the overshoot is limited to 1%,and the settling time does not exceed 3 s.Moreover,compared to the traditional method,the proposed method exhibits higher adaptability to model errors and variations in flight conditions.In the conducted semi-physical simulation experiments,the proposed method achieves stable control of a real electric pump. 展开更多
关键词 Actuator delay ATR engines Neural network control Reinforcement learning Semi-physical simulation
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Machine learning approaches to early detection of delayed wound healing following gastric cancer surgery
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作者 Duygu Kirkik Huseyin Murat Ozadenc Sevgi Kalkanli Tas 《World Journal of Gastrointestinal Oncology》 2026年第1期287-290,共4页
Delayed wound healing following radical gastrectomy remains an important yet underappreciated complication that prolongs hospitalization,increases costs,and undermines patient recovery.In An et al’s recent study,the ... Delayed wound healing following radical gastrectomy remains an important yet underappreciated complication that prolongs hospitalization,increases costs,and undermines patient recovery.In An et al’s recent study,the authors present a machine learning-based risk prediction approach using routinely available clinical and laboratory parameters.Among the evaluated algorithms,a decision tree model demonstrated excellent discrimination,achieving an area under the curve of 0.951 in the validation set and notably identifying all true cases of delayed wound healing at the Youden index threshold.The inclusion of variables such as drainage duration,preoperative white blood cell and neutrophil counts,alongside age and sex,highlights the pragmatic appeal of the model for early postoperative monitoring.Nevertheless,several aspects warrant critical reflection,including the reliance on a postoperative variable(drainage duration),internal validation only,and certain reporting inconsistencies.This letter underscores both the promise and the limitations of adopting interpretable machine learning models in perioperative care.We advocate for transparent reporting,external validation,and careful consideration of clinically actionable timepoints before integration into practice.Ultimately,this work represents a valuable step toward precision risk stratification in gastric cancer surgery,and sets the stage for multicenter,prospective evaluations. 展开更多
关键词 Gastric cancer Radical gastrectomy Delayed wound healing Machine learning Decision tree Risk prediction
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Atomistic Insights into Aluminium-Boron Nitride Nanolayered Interconnects for High-Performance VLSI Systems
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作者 Mallikarjun P.Y. Rame Gowda D.N. +4 位作者 Trisha J.K. Varshini M. Poornesha S.Shetty Mandar Jatkar Arpan Shah 《Computers, Materials & Continua》 2026年第3期641-655,共15页
As circuit feature sizes approach the nanoscale,traditional Copper(Cu)interconnects face significant hurdles posed by rising resistance-capacitance(RC)delay,electromigration,and high power dissipation.These limitation... As circuit feature sizes approach the nanoscale,traditional Copper(Cu)interconnects face significant hurdles posed by rising resistance-capacitance(RC)delay,electromigration,and high power dissipation.These limitations impose constraints on the scalability and reliability of future semiconductor technologies.Our paper describes the new Vertical multilayer Aluminium Boron Nitride Nanoribbon(AlBN)interconnect structure,integrated with Density functional theory(DFT)using first-principles calculations.This study explores AlBN-based nanostructures with doping of 1Cu,2Cu,1Fe(Iron),and 2Fe for the application of Very Large Scale Integration(VLSI)interconnects.The AlBN structure utilized the advantages of vertical multilayer interconnects to both reduce the RC delay while enhancing signal integrity.Key parameters like Fermi energy,bandgap,binding energy,conduction channels,quantum resistance,and RC delay were analyzed.Through modeling and large-scale simulation,the structural,electronic,and stability attributes of the AlBN interconnects are analyzed,and the results illustrate considerable improvements in signal propagation against Cu interconnect structures.These findings confirm the tunable,high-performance nature of AlBN-2Fe,making it a promising candidate for future high-speed,low-power VLSI interconnect technologies.We demonstrated an advanced energy-efficient interconnect that can be easily scaled for future nanoscale VLSI circuit design and gives rise to a next generation of viable interconnect technology for high-capacity,high-speed,reliable semiconductor technology. 展开更多
关键词 Dielectric materials AlBN interconnects RC delay reduction nanoscale electronics semiconductor technology signal integrity
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Characterization of the susceptibility of ore particles to breakdown in high voltage pulse breakage and the influencing factors
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作者 Rui Sun Yang Hong +5 位作者 Daqian Wang Liang Si Jianguo Yang Wei Huang Liefeng Huang Weiran Zuo 《International Journal of Mining Science and Technology》 2026年第1期113-124,共12页
The susceptibility of ore particles to electrical breakdown plays a critical role for high voltage pulse(HVP)breakage,yet its quantitative characterization still lacks deep understanding.Two indicators,namely breakdow... The susceptibility of ore particles to electrical breakdown plays a critical role for high voltage pulse(HVP)breakage,yet its quantitative characterization still lacks deep understanding.Two indicators,namely breakdown delay time(T_(d))and breakdown strength(E_(b))were compared,based on analysis on the two breakdown modes namely wavefront mode and post-wave mode.It was found that T_(d) is more suitable to characterize the susceptibility of ore particles to electrical breakdown in HVP breakage than E_(b).A probabilistic model based on the Weibull distribution is developed to describe the relation of breakdown probability to T_(d).Regression analyses were conducted to investigate how operating parameters and particle properties influence Td and size reduction degree of ore particles in HVP breakage.The regressed models demonstrate potential capability to predict metallic minerals content and HVP breakage degree based on operating parameters and particle properties. 展开更多
关键词 Electrical breakdown High voltage pulse breakage SUSCEPTIBILITY Breakdown delay time
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In situ Generation of Carbazole-triazine Thermally Activated Delayed Fluoresscence Emitters within the Conjugated Polymer Chain
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作者 Alexander M.Mitroshin Serguei A.Miltsov +9 位作者 Ilya E.Kolesnikov Dmitriy A.Lypenko Artem V.Dmitriev Larisa S.Litvinova Vladislav M.Korshunov Ilya V.Taydakov Elena V.Ushakova Anastasia V.Rogova Felix N.Tomilin Alexander V.Yakimansky 《Chinese Journal of Polymer Science》 2026年第2期361-370,I0009,共11页
The development of polymeric materials that exhibit blue thermally activated delayed fluorescence(TADF)is of great interest for optoelectronic applications.However,achieving TADF in polymers often requires an elaborat... The development of polymeric materials that exhibit blue thermally activated delayed fluorescence(TADF)is of great interest for optoelectronic applications.However,achieving TADF in polymers often requires an elaborate monomer design.The high-energy local triplet state(^(3)LE)of carbazole complicates its application despite the molecular orbital arrangement being suitable for blue emission.Here,we present an approach to polymer design that makes it possible to solve this problem.We demonstrate the in situ formation of a TADF donor-acceptor system during Suzuki polycondensation,creating an extended carbazole-based donor matrix coupled with a triazine acceptor.The resulting polymer exhibited efficient TADF with a low energy gap(ΔE_(ST))value if a phenyl N-substituent,enabling essential electron delocalization,was present in the carbazole moiety.This work establishes a versatile platform for developing carbazole-based TADF polymers,overcoming the fundamental limitations that hinder their widespread application. 展开更多
关键词 Thermally activated delayed fluorescence(TADF) POLYCARBAZOLE Suzuki polycondensation Photoluminescence
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Probabilistic fault-tolerant fuzzy control for adaptive event-triggered lane-keeping system of autonomous electric vehicles
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作者 Guoshun Cai Guodong Yin +3 位作者 Jiwei Feng Weihua Wang Zhenwu Fang Chaobin Zhou 《Chinese Journal of Mechanical Engineering》 2026年第1期453-468,共16页
Realistic faults and failures often occur probabilistically in the lane-keeping system of autonomous electric vehicles,reducing system reliability and posing significant challenges to driving safety.To enhance the sys... Realistic faults and failures often occur probabilistically in the lane-keeping system of autonomous electric vehicles,reducing system reliability and posing significant challenges to driving safety.To enhance the system resilience,this paper proposes a novel robust fuzzy fault-tolerant control strategy that incorporates the adaptive event-trigger(AET)mechanism to realize stable,reliable,and precise lane-keeping control in the presence of multiple system uncertainties and probabilistic faults.First,to capture the uncertain and time-varying nature of tire cornering stiffness,an effective Takagi-Sugeno(T-S)fuzzy tire model is developed.Then,by employing the distribution-based probabilistic approach,two sets of unrelated random variables,random sensor and actuator faults in the control system,are modeled.Next,to improve communication efficiency and address ineluctable network-induced delays,an AET control framework with a well-designed triggering condition is established.Subsequently,a robust fuzzy output feedback fault-tolerant lane-keeping controller that satisfies the H∞per-formance is designed by using the Lyapunov-Krasovski functional method.Furthermore,the mean-square ex-ponential stability of the closed-loop system is rigorously guaranteed.Finally,real-time simulations based on Carsim/Simulink co-simulation platform under dynamic driving conditions demonstrate the feasibility and ef-fectiveness of the proposed control strategy. 展开更多
关键词 Autonomous vehicles Lane-keeping control Event-triggered control Probabilistic sensor and actuator faults Network-induced delay
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Vibrations induced by time-delayed double blastholes in underground rocks:Experimental study and theoretical analysis
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作者 Yonggang Gou Gui Yang +2 位作者 Xianyang Qiu Kun Ji Yumin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1108-1125,共18页
Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while... Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while the potential for further vibration reduction remains debated,largely due to unclear underlying mechanisms.In light of the popularization of electronic detonators and the representativeness of double-hole configurationsfor multiple blastholes,it is essential to investigate the vibration characteristics induced by time-delayed double blastholes.Therefore,a series of doubleborehole experimental blasts was conducted in an underground roadway to clarify the variation in vibration from single-hole to dual-hole conditions.Based on the experimental data and inherent limitations,an exact full-fieldtheoretical model was further employed to systematically analyze the effects of delay time,charge length,and borehole inclination angle on vibrations induced by various doublehole configurations.The experimental data and theoretical analysis reveal that the general scaled distance effectively predicts vibrations in delayed blasting but does not reflectvibration reduction.Increasing delay time causes fluctuatingPPVs,which stabilize slightly above single-hole PPVs as delay times exceed a certain value.The delayed blasting primarily reduces near-fieldfrequencies.Longer charge lengths in double boreholes increase PPV levels and attenuation rates within a certain length,and the vibration behavior of combined long and short charge lengths is governed by the long blasthole.Larger blasthole inclination angles enhance vibration amplitude and reduce PPV attenuation rates.Optimizing inclination angles is more critical than adjusting delay times,and parallel boreholes offer the best vibration control. 展开更多
关键词 Vibration of double blastholes Experimental data Theoretical model Delay time Wave superposition
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Mechanism of action of synaptic mitochondrial damage in delayed cognitive recovery
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作者 Huihui Miao Qiang Liu +7 位作者 Yan-Ping Liu Bin-Bin Yan Xin-Hao Jiao Hai-Bi Wang Cheng-Hua Zhou Tianzuo Li Zhongcong Xie Yuqing Wu 《Neural Regeneration Research》 2026年第6期2457-2466,共10页
Delayed neurocognitive recovery following anesthesia and surgery is a common complication in older adult patients.Synapses are fundamental to cognitive function.The activity of synapses heavily depends on the energy s... Delayed neurocognitive recovery following anesthesia and surgery is a common complication in older adult patients.Synapses are fundamental to cognitive function.The activity of synapses heavily depends on the energy supplied by synaptic mitochondria,which are significantly influenced by oxidative stress.Sirtuin 3 is a histone deacetylase located in the mitochondrial matrix that plays a pivotal role in regulating mitochondrial function.However,it remains unclear whether and how sirtuin 3 is involved in the development of delayed cognitive recovery.Therefore,in this study,we investigated the potential role of sirtuin 3 in synapses during delayed neurocognitive recovery.Our results showed that anesthesia and surgery induced cognitive impairment in mice and reduced sirtuin 3 protein expression.Overexpression of sirtuin 3 inhibited opening of the mitochondrial permeability transition pore by reducing acetylation of K166 on cyclophilin D and also rescued cognitive impairment.Aged mice carrying the cyclophilin D-K166R mutation exhibited significantly reduced cognitive impairment.Similarly,administering the mitochondrial permeability transition pore blocker,cyclosporine A,effectively alleviated the decline in synaptic mitochondrial function and cognitive impairment caused by anesthesia and surgery in aged mice.These results indicate that the sirtuin 3/cyclophilin D-K166/mPTP signaling pathway in hippocampal synaptic mitochondria is involved in delayed neurocognitive recovery of aged mice,suggesting this pathway could serve as a potential target for treatment. 展开更多
关键词 acetylase aged mice cyclophilin D delayed neurocognitive recovery hippocampus long-term potentiation mitochondrial permeability transition pore sirtuin 3 synaptic mitochondria SYNAPTOSOME
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Noise-driven enhancement for exploration:Deep reinforcement learning for UAV autonomous navigation in complex environments
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作者 Haotian ZHANG Yiyang LI +1 位作者 Lingquan CHENG Jianliang AI 《Chinese Journal of Aeronautics》 2026年第1期454-471,共18页
Unmanned Aerial Vehicle(UAV)plays a prominent role in various fields,and autonomous navigation is a crucial component of UAV intelligence.Deep Reinforcement Learning(DRL)has expanded the research avenues for addressin... Unmanned Aerial Vehicle(UAV)plays a prominent role in various fields,and autonomous navigation is a crucial component of UAV intelligence.Deep Reinforcement Learning(DRL)has expanded the research avenues for addressing challenges in autonomous navigation.Nonetheless,challenges persist,including getting stuck in local optima,consuming excessive computations during action space exploration,and neglecting deterministic experience.This paper proposes a noise-driven enhancement strategy.In accordance with the overall learning phases,a global noise control method is designed,while a differentiated local noise control method is developed by analyzing the exploration demands of four typical situations encountered by UAV during navigation.Both methods are integrated into a dual-model for noise control to regulate action space exploration.Furthermore,noise dual experience replay buffers are designed to optimize the rational utilization of both deterministic and noisy experience.In uncertain environments,based on the Twin Delay Deep Deterministic Policy Gradient(TD3)algorithm with Long Short-Term Memory(LSTM)network and Priority Experience Replay(PER),a Noise-Driven Enhancement Priority Memory TD3(NDE-PMTD3)is developed.We established a simulation environment to compare different algorithms,and the performance of the algorithms is analyzed in various scenarios.The training results indicate that the proposed algorithm accelerates the convergence speed and enhances the convergence stability.In test experiments,the proposed algorithm successfully and efficiently performs autonomous navigation tasks in diverse environments,demonstrating superior generalization results. 展开更多
关键词 Action space exploration Autonomous navigation Deep reinforcement learning Twin delay deep deterministic policy gradient Unmanned aerial vehicle
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Phase Shifting Analysis and Solution for UCA Based OAM Beam Steering
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作者 Yu Wei Zhou Bin Bu Zhiyong 《China Communications》 2026年第2期35-50,共16页
Recently,uniform circular array(UCA)based orbital angular momentum(OAM)beam steering schemes have been proposed to overcome the limitations of coaxial transmission.Unlike the traditional multiple-input-multiple-output... Recently,uniform circular array(UCA)based orbital angular momentum(OAM)beam steering schemes have been proposed to overcome the limitations of coaxial transmission.Unlike the traditional multiple-input-multiple-output(MIMO)beam steering,OAM beam steering includes both the OAM generation and the beam steering.Generally,the true time delay(TTD)or the phase shifter(PS)are required for beam steering in the radio domain.Previous studies suggest that TTD is preferred for wideband MIMO beam steering to avoid beam squint caused by PS.However,in this paper,we theoretically prove that to generate the OAM beam ideally,PS should be used,while TTD deteriorates the mode orthogonality,which is influenced by the relative bandwidth.Once the ideal OAM beam is generated,TTD is required to prevent beam squint.Based on this analysis,we propose to use the two-stage phase-shifting(TSPS)architecture for OAM beam steering:PS for OAM generation and TTD for beam steering.Simulation results suggest that compared to the spectrum efficiency(SE)of PS based OAM communication,the SE based on the TTD significantly declines as the relative bandwidth increases.Furthermore,OAM beam steering using the TSPS architecture greatly outperforms systems that adopt a single TTD or PS network. 展开更多
关键词 beam steering orbital angular momentum(OAM) phase shifter(PS) true time delay(TTD) uniform circular array(UCA)
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A Cost-Effective Approach to Precisely Estimate Singlet-Triplet Energy Gaps in MR-TADF Molecules:Combining Delta Self-Consistent Field and Time-Dependent Density Functional Theory Methods
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作者 Qian Jina Dong Wang 《Chinese Journal of Chemical Physics》 2026年第1期41-50,I0021-I0032,I0042,共23页
As a novel class of purely organic fluores-cent materials,multiple resonance thermal-ly activated delayed fluorescence(MR-TADF)compounds hold significant promise for next-generation display technologies.The efficiency... As a novel class of purely organic fluores-cent materials,multiple resonance thermal-ly activated delayed fluorescence(MR-TADF)compounds hold significant promise for next-generation display technologies.The efficiency of exciton utilization and the overall performance of organic light-emit-ting devices are closely linked to the singlet-triplet energy gap(ΔE_(ST))of MR-TADF emitters.Identifying an economic and accu-rate theoretical approach to predictΔE_(ST)would be beneficial for high-throughput screening and facilitate the inverse design of MR-TADF molecules.In this study,we evaluated the S_(1)state energy(E(S_(1))),T_(1)state ener-gy(E(T_(1))),andΔE_(ST)using three different physical interpretations:adiabatic excitation ener-gy,vertical absorption energy,and vertical emission energy.We employed the time-depen-dent density functional theory(TDDFT)and delta self-consistent field(ΔSCF)methods to calculate E(S_(1)),E(T_(1)),andΔE_(ST)for 20 MR-TADF molecules reported in the literature.We compared these calculated values with experimental data obtained from fluorescence spec-troscopy at room-temperature(or 77 K)and phosphorescence spectroscopy conducted at 77 K.Our findings indicate that the vertical absorption energy at the S0 state minimum,deter-mined by theΔSCF method,accurately predicts the S_(1)state energy.Similarly,the vertical absorption energy at the S0 state minimum,calculated using the TDDFT method,effectively predicts the T_(1)state energy.TheΔE_(ST)derived from the difference between these two excita-tion energies exhibited the smallest mean absolute error of only 0.039 eV compared to the ex-perimental values.This combination represents the most accurate and cost-effective method reported to date for predicting theΔE_(ST)of MR-TADF molecules,and can be integrated into AI-driven inverse design workflows for new emitters. 展开更多
关键词 Organic light-emitting diode Multiple resonance thermally activated delayed fluorescence emitter Single-triplet energy gap Delta self-consistent field method Time-de-pendent density functional theory method
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