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Eco-physiological characteristics of Tetracentron sinense *** in response to different light intensities

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Journal of Forestry Research 2024年第3期35卷 29-44页

作者： Rong Wang Xueheng Lu Hongyan Han Xuemei Zhang Yonghong Ma Qinsong Liu Xiaohong gan k.y Laboratoryof Southwest Wildlife Resources Conservation Ministry of EducationChina West Normal UniversityNanchong 637009People's Republic of China Institute of Plant Adaptation and Utilization in Southwest Mountain China West Normal UniversityNanchong 637009People's Republic of China Office of the People's Government of Yuexi County Yuexi County 616650Liangshan Yi Autonomous PrefecturePeople's Republic of China

The regeneration of Tetracentron sinense *** poor in the understory and in open areas due to the charac-teristics of natural regeneration of the species on forest edges and in *** is unclear whether different light intensities in various habitats affect eco-physiological characteristics of saplings and their natural *** this study,the light intensity in *** habitats was simulated by artificial shading(L1:100%NS(natural sunlight)in the open;L2:50%NS in a forest gap or edge;L3:10%NS in understory)to investigate differences in morphology,leaf structure,physiology,and photosynthesis of 2-year-old sap-lings,and to analyze the mechanism of light intensity on sapling *** differences were observed in morphology(including leaf area,and specific leaf area)under different light *** to L1 and L3,chloroplast structure in L2 was *** increasing time,superoxide dismutase(SOD)and catalase(CAT)activities in L2 became gradually higher than under the other light intensities,while malondialdehyde(MDA)content was *** decreased osmoregulation substance contents of leaves but increased *** results suggest that light intensities significantly affect the eco-physiological characteristics of *** saplings and they would respond most favorably at intermediate levels of light by optimizing eco-physiological ***,50%natural sunlight should be created to promote saplings establishment and population recovery of *** during in situ conservation,including sowing mature seeds in forest edges or gaps and providing appropriate shade protection for seedlings and saplings in the open.

关键词： Chloroplast ultrastructure Eco-physiological characteristics Light intensities Sapling establishment Tetracentron sinense Oliv

Numerical Simulation of the Mass Movement Process of the 2018 Sedongpu Glacial Debris Flow by Using the Fluid-Solid Coupling Method

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Journal of Earth Science 2024年第2期35卷 583-596页

作者： Xing-Yu Long Yu-Xiang Hu Bin-Rui gan Jia-Wen Zhou State k.y Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu610065China College of Water Resource and Hydropower Sichuan UniversityChengdu610065China

In the context of global warming and intensified human activities,glacier instability in plateau regions has increased,and glacier debris flows have become active,which poses a significant threat to the lives and property of people and socioeconomic *** mass movement process of glacier debris flows is extremely complex,so this paper uses the 2018 Sedongpu glacier debris flow event on the Qinghai-Tibet Plateau as an example and applies a numerical simulation method to invert the whole process of mass *** view of the interaction between phases in the process of motion,we use the fluid-solid coupling method to describe the mass *** granular-flow model and drift-flux model are employed in FLOW3D software to study the mass movement process of glacier debris flows and explore their dynamic *** results indicate that the glacier debris flow lasted for 700 s,and the movement process was roughly divided into four stages,including initiation,scraping,surging and deposition;the depositional characteristics calculated by the fluid-solid coupling model are consistent with the actual survey results and have good reliability;strong erosion occurs during the mass movement,the clear volume amplification effect,and the first wave climbs 17.8 m across the *** fluid-solid coupling method can better simulate glacier debris flows in plateau regions,which is helpful for the study of the mechanism and dynamic characteristics of such disasters.

关键词： glacial debris flow Qinghai-Tibet Plateau fluid-solid coupling FLOW3D mass movement depositional characteristics disasters engineering geology

CNN-LSTM based incremental attention mechanism enabled phase-space reconstruction for chaotic time series prediction

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Journal of Electronic Science and Technology 2024年第2期22卷 77-90页

作者： Xiao-Qian Lu Jun Tian Qiang Liao Zheng-Wu Xu Lu gan Bidding and Purchasing Center University of Electronic Science and Technology of ChinaChengdu611731China Yibin Research Institute University of Electronic Science and Technology of ChinaYibin644000China School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu611731China

To improve the prediction accuracy of chaotic time series and reconstruct a more reasonable phase space structure of the prediction network.we propose a convolutional neural network.long short-term memory(CNN-LSTM)prediction model based on the incremental attention ***,a traversal search is conducted through the traversal layer for finite parameters in the phase ***,an incremental attention layer is utilized for parameter judgment based on the dimension weight criteria(DWC).The phase space parameters that best meet DWC are selected and fed into the input ***,the constructed CNN-LSTM network.extracts spatio-temporal features and provides the final prediction *** model is verified using Logistic,Lorenz,and sunspot chaotic time series,and the performance is compared from the two dimensions of prediction accuracy and network.phase space ***,the CNN-LSTM network.based on incremental attention is compared with long short-term memory(LSTM),convolutional neural network.CNN),recurrent neural network.RNN),and support vector regression(SVR)for prediction *** experiment results indicate that the proposed composite network.model possesses enhanced capability in extracting temporal features and achieves higher prediction ***,the algorithm to estimate the phase space parameter is compared with the traditional CAO,false nearest neighbor,and C-C,three typical methods for determining the chaotic phase space *** experiments reveal that the phase space parameter estimation algorithm based on the incremental attention mechanism is superior in prediction accuracy compared with the traditional phase space reconstruction method in five network.,including CNN-LSTM,LSTM,CNN,RNN,and SVR.

关键词： Chaotic time series Incremental attention mechanism Phase-space reconstruction

Quantum Spin Exchange Interactions to Accelerate the Redox k.netics in Li–S Batteries

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Nano-Micro Letters 2024年第5期16卷 370-383页

作者： Yu Du Weijie Chen Yu Wang Yue Yu k.i Guo gan Qu Jianan Zhang k.y Laboratory of Advanced Energy Catalytic and Functional Materials Preparation of Zhengzhou City College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001People’s Republic of China

Spin-engineering with electrocatalysts have been exploited to suppress the“shuttle effect”in Li–S *** selec-tion,spin-dependent electron mobility and spin potentials in activation barriers can be optimized as quantum spin exchange interactions lead-ing to a significant reduction of the electronic repulsions in the orbitals of ***,we anchor the MgPc molecules on fluorinated carbon nanotubes(MgPc@FCNT),which exhibits the single active Mg sites with axial *** to the density functional theory calculations,the electronic spin polarization in MgPc@FCNT not only increases the adsorption energy toward LiPSs intermediates but also facilitates the tunneling process of electron in Li–S *** a result,the MgPc@FCNT provides an initial capacity of 6.1 mAh cm^(-2) even when the high sulfur loading is 4.5 mg cm^(-2),and still maintains 5.1 mAh cm^(-2) after 100 *** work.provides a new perspective to extend the main group single-atom catalysts enabling high-performance Li–S batteries.

关键词： Metal phthalocyanines Spin polarization Electrocatalysis Li–S batteries

Multi-Fidelity Simulation of Gas Turbine Overall Performance by Directly Coupling High-Fidelity Models of Multiple Rotating Components

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Journal of Thermal Science 2024年第4期33卷 1357-1378页

作者： DENG Weimin XU Yibing NI Ming WEI Zuojun gan Xiaohua REN Guangming Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen518055China School of Aerospace Engineering Tsinghua UniversityBeijing100084China Shenzhen k.y Laboratory of Wide-Speed-Range and Variable-Density Continuous Wind Tunnel Shenzhen Science and Technology Innovation CommitteeShenzhen518000China

Multi-fidelity simulations incorporate computational fluid dynamics(CFD) models into a thermodynamic model,enabling the simulation of the overall performance of an entire gas turbine with high-fidelity *** iterative coupled methods rely on characteristic maps,while fully coupled methods directly incorporate high-fidelity ***,fully coupled methods face challenges in simulating rotating components,including weak.convergence and complex *** address these challenges,a fully coupled method with logarithmic transformations was developed to directly integrate high-fidelity CFD models of multiple rotating *** developed fully coupled method was then applied to evaluate the overall performance of a k.66 micro gas turbine across various off-design *** developed fully coupled method was also compared with the traditional iterative coupled ***,experimental data from ground tests were conducted to verify its *** convergence history indicated that the proposed fully coupled method exhibited stable convergence,even under far-off-design *** experimental verification demonstrated that the multi-fidelity simulation with the fully coupled method achieved high accuracy in off-design *** analysis revealed inherent differences in the coupling methods of CFD models between the developed fully coupled and traditional iterative coupled *** inherent differences provide valuable insights for reducing errors between the component-level model and CFD models in different coupling *** developed fully coupled method,introducing logarithmic transformations,offers more realistic support for the detailed and optimal design of high-fidelity rotating components within the overall performance platform of gas turbines.

关键词： multi-fidelity fully coupled method iterative coupled method gas turbine component-level model

Perception Enhanced Deep Deterministic Policy Gradient for Autonomous Driving in Complex Scenarios

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 557-576页

作者： Lyuchao Liao Hank.n Xiao Pengqi Xing Zhenhua gan Youpeng He Jiajun Wang Fujian Provincial k.y Laboratory of Automotive Electronics and Electric Drive Fujian University of TechnologyFuzhou350118China Fujian Provincial Universities Engineering Research Center for Intelligent Driving Technology Fuzhou350118China

Autonomous driving has witnessed rapid advancement;however,ensuring safe and efficient driving in intricate scenarios remains a critical *** particular,traffic roundabouts bring a set of challenges to autonomous driving due to the unpredictable entry and exit of vehicles,susceptibility to traffic flow bottleneck.,and imperfect data in perceiving environmental information,rendering them a vital issue in the practical application of autonomous *** address the traffic challenges,this work.focused on complex roundabouts with multi-lane and proposed a Perception EnhancedDeepDeterministic Policy Gradient(PE-DDPG)for AutonomousDriving in the ***,themodel incorporates an enhanced variational autoencoder featuring an integrated spatial attention mechanism alongside the Deep Deterministic Policy Gradient framework.enhancing the vehicle’s capability to comprehend complex roundabout environments and mak. ***,the PE-DDPG model combines a dynamic path optimization strategy for roundabout scenarios,effectively mitigating traffic bottleneck. and augmenting throughput *** experiments were conducted with the collaborative simulation platform of CARLA and SUMO,and the experimental results show that the proposed PE-DDPG outperforms the baseline methods in terms of the convergence capacity of the training process,the smoothness of driving and the traffic efficiency with diverse traffic flow patterns and penetration rates of autonomous vehicles(AVs).Generally,the proposed PE-DDPGmodel could be employed for autonomous driving in complex scenarios with imperfect data.

关键词： Autonomous driving traffic roundabouts deep deterministic policy gradient spatial attention mechanisms

MCP-1 and IL-4 encapsulated hydrogel particles with macrophages enrichment and polarization capabilities for systemic lupus erythematosus treatment

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Nano Research 2024年第9期17卷 8316-8324页

作者： Shengjie Zhu Danqing Huang Qichen Luan Yang Li Jingjing gan Yuanjin Zhao Lingyun Sun Department of Rheumatology and Immunology Nanjing Drum Tower HospitalClinical Medical College of Traditional Chinese and Western MedicineNanjing University of Chinese MedicineNanjing 210096China State k.y Laboratory of Bioelectronics School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China

Macrophages play a pivotal role in systemic lupus erythematosus(SLE)*** have been made to develop multifunctional drug delivery systems capable of directing macrophage ***,we present a novel hyaluronic acid methacrylate(HAMA)hydrogel microparticle encapsulating multiple cytok.nes for SLE remission though enhancing macrophage *** HAMA microparticles loaded with monocyte chemotactic protein-1(MCP-1)and interleuk.n-4(IL-4)were fabricated by using a microfluidic *** released MCP-1 facilitates the aggregation of inflammatory macrophages,after which IL-4 induces the macrophage phenotype shift from inflammatory M1 to immune-protective M2,thus restoring immune *** have demonstrated in MRL/lpr mice that the hydrogel microparticles could improve their efficacy of intraperitoneal drug delivery,modulate immune function,and attenuate the disease *** results suggest that our proposed microparticles delivery platform has potential clinical value for treating autoimmune diseases.

关键词： microfluidics M2 polarization hydrogel drug delivery systemic lupus erythematosus(SLE)

Wearable ultrasensitive and rapid human physiological monitoring based on microfiber Sagnac interferometer

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Science China(Information Sciences) 2024年第3期67卷 281-290页

作者： Xin WANG Hongyou ZHOU Meihua CHEN Yongcheng HE Zhishen ZHANG Jiulin gan Zhongmin YANG State k.y Laboratory Luminescent Materials and Devices Institute of Optical Communication MaterialsSpecial Glass Fiber and Device Engineering Technology Research and Development Center of Guangdong ProvinceGuangdong Provincial Key Laboratory of Fiber Laser Materials and Applied TechniquesSouth China University of Technology Guangdong-Hong k.ng-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology Foshan University

High-sensitive and fast-responding flexible strain sensors are essential for the smart wearable devices that precisely and dynamically perceive the weak.deformations induced by human physiological signals. Here, a flexible strain sensor via polydimethylsiloxane(PDMS)-encapsulated microfiber Sagnac interferometer was designed and prepared for monitoring the human pulse signals and sound vibrations. The sensor achieved a record-break.ng sensitivity(gauge factor, GF = 9977) and an extremely low detection limit(0.00025%) due to the strong polarization-dependent coupling effect in the microfiber coupler and the polarization-mixing effect in the Sagnac loop. The relative intensity demodulation method also enabled a fast response time of 10 μs. The wearable pulse measurements were implemented by attaching this flexible strain sensor directly to human sk.n at various locations and the waveform details were accurately captured. Tak.ng advantage of the ultra-high sensitivity and fast response performance of the prepared sensor, the real-time dynamic acquisition of the underwater weak.signal, such as the hydro-acoustic waves with a wide range of 20 Hz–16.86 k.Hz, has been demonstrated. These initial results pave the way for a new and innovative category of underwater wearable devices with rapid detection of human physiological signals and weak.environmental vibrations.

关键词： flexible strain sensor microfiber Sagnac interferometer underwater detection

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Resolving aging dynamics of a 3D colloidal glass

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 110-118页

作者： XiaoJuan Wang Jun Duan gan Ding YunZhuo Lu Xing Lu LanHong Dai MinQiang Jiang State k.y Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116028China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Physical aging is an inherent property of glassy matter, but understanding its microscopic mechanism remains a challenge particularly at the particle level. In this work. we use a confocal microscope to in-situ trace the particle trajectories in a 3D colloidal glass for 73000 s, aiming at resolving the aging dynamics. By calculating the mean square displacement of particle motions, we find that the glass aging with time can be divided into three stages: β relaxation, α relaxation and free diffusion. The system's mean square displacement at each aging state is quantitatively resolved into three contributions of particle dynamics modes: vibration within the nearest-neighbor cages, hopping between cages and cooperative rearrangement. We further calculate the particle's free volume and find that the β-to-α transition is accompanied by the temporary increase of the system-averaged free volume due to pronounced hops of particles. Nevertheless, the temporal autocorrelation of the free volume spatial distribution still obeys a monotonically stretched exponential decay with an exponent of 0.76, which is related to the sub-diffusion dynamics of cooperative rearrangements and hops mixed in α relaxation. According to the resolved vibrational displacements,we calculate the vibrational density of states of this 3D glass, and the characteristic boson peak.is reproduced at low *** findings shed insight into the particle-level aging dynamics of a real glass under purely thermal activation.

关键词： colloidal glass physical aging particle dynamics free volume boson peak