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Adaptive entry guidance for the Tianwen-1 mission

Astrodynamics 2022年第1期6卷 17-26页

作者： Minwen Guo Xiangyu Huang Maodeng Li Jinchang Hu Chao Xu Beijing Institute of Control Engineering Beijing 100094China National Key Laboratory of Science and Technology on Space Intelligent Control Beijing 100094China

To meet the requirements of the Tianwen-1 mission,adaptive entry guidance for entry vehicles,with low lift-to-drag ratios,limited control authority,and large initial state bias,was ***,the entry guidance law is divided into four distinct phases:trim angle-of-attack phase,range control phase,heading alignment phase,and trim-wing deployment *** the range control phase,the predictor–corrector guidance algorithm is improved by planning an on-board trajectory based on the Mars science laboratory(MSL)entry guidance *** nominal trajectory was designed and described using a combination of the downrange value and other states,such as drag acceleration and altitude *** a large initial state bias,the nominal downrange value was modified onboard by weighing the landing accuracy,control authority,and parachute deployment *** biggest advantage of this approach is that it allows the successful correction of altitude errors and the avoidance of control *** overview of the optimal trajectory design process,including a discussion of the design of the initial flight path angle,relevant event trigger,and transition conditions between the four phases,was also ***,telemetry data analysis and post-flight assessment results were used to illustrate the adaptive guidance law,create good conditions for subsequent parachute reduction and power reduction processes,and gauge the success of the mission.

关键词： Tianwen-1 mission adaptive entry guidance on-board trajectory planning telemetry data analysis post-flight assessment

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Plastic materials and water sources actively select and shape wastewater plastispheres over time

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Frontiers of Environmental science & Engineering 2022年第11期16卷 233-242页

作者： Yu Xia Xuyang Zhang Miao Zhang Liming Chen Xiaotong Tang Yuhong Sun Xiang Li School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China

The daily use of plastics presents a serious pollution issue due to their extremely slow *** and the biofilm that grows on plastics(i.e.,the plastisphere)are important subsets of plastic *** studies have been conducted to reveal the structures of the plastispheres,the driving factors for the formation of the plastisphere,and the ability of the plastispheres to degrade plastics in a variety of water ***,the plastispheres related to wastewater are *** this study,we used a microcosmic strategy to study the evolution of the plastispheres associated with microplastics(MPs)over time in *** found that plastic materials and water sources did not actively select and shape the plastispheres at an early stage,but the active selection for a unique niche of the plastisphere occurred after 14 d of *** addition,we confirmed that the alkB gene was densely present,and metagenomics showed some additional chemical reactions,which suggests that MPs are consumed by the microbes in the ***,metagenomics identified some metagenome-assembled genomes(MAGs)associated with high-density polyethylene(HDPE)and polyethylene terephthalate(PET).The identification of HDPE-associated MAGs and PET-associated MAGs further supports the notion that the selection for a unique niche of the plastisphere is driven by plastic materials and water sources(in this study,after 14 d of growth).Our discoveries bring new views on the behavior of the wastewater-associated plastisphere,especially how long it takes a wastewater plastisphere to form.

关键词： Microplastics Whole-genome metagenomic sequencing Plastisphere Plastic degradation MHETase

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Powered-descent landing GNC system design and flight results for Tianwen-1 mission

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Astrodynamics 2022年第1期6卷 3-16页

作者： Xiangyu Huang Chao Xu Jinchang Hu Maodeng Li Minwen Guo Xiaolei Wang Yu Zhao Baocheng Hua Yunpeng Wang Beijing Institute of Control Engineering Beijing 100094China National Key Laboratory of Science and Technology on Space Intelligent Control Beijing 100094China

The powered-descent landing(PDL)phase of the Tianwen-1 mission began with composite backshell–parachute(CBP)separation and ended with landing-rover *** main tasks of this phase were to reduce the velocity of the lander,perform the avoidance maneuver,and guarantee a soft *** PDL phase overcame many challenges:performing the divert maneuver to avoid collision with the CBP while simultaneously avoiding large-scale hazards;slowing the descent from approximately 95 to 0 m/s;performing the precise hazard-avoidance maneuver;and placing the lander gently and safely on the surface of *** architecture and algorithms of the guidance,navigation,and control system for the PDL phase were designed;its execution resulted in Tianwen-1’s successful touchdown in the morning of 15 May ***,the Tianwen-1 mission achieved a historic autonomous landing with simultaneous hazard and CBP avoidance.

关键词： Tianwen-1 powered-descent landing(PDL) guidance,navigation,and control(GNC) backshell avoidance hazard avoidance

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Atmospheric nitrogen deposition affects forest plant and soil system carbon:nitrogen:phosphorus stoichiometric flexibility:A meta-analysis

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Forest Ecosystems 2024年第3期11卷 307-317页

作者： Xiyan Jiang Xiaojing Wang Yaqi Qiao Yi Cao Yan Jiao An Yang Mengzhou Liu Lei Ma Mengya Song Shenglei Fu Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions College of Geography and Environmental ScienceHenan UniversityKaifeng475004China Henan Key Laboratory of Integrated Air Pollution Control and Ecological Security College of Geography and Environmental ScienceHenan UniversityKaifeng475004China Henan Dabieshan National Field Observation and Research Station of Forest Ecosystem Henan UniversityZhengzhou450046China

Background:Nitrogen(N)deposition affects forest stoichiometric flexibility through changing soil nutrient availability to influence plant ***,the effect of N deposition on the flexibility of carbon(C),N,and phosphorus(P)in forest plant-soil-microbe systems remains ***:We conducted a meta-analysis based on 751 pairs of observations to evaluate the responses of plant,soil and microbial biomass C,N and P nutrients and stoichiometry to N addition in different N intensity(050,50–100,>100 kg·ha^(-1)·year^(-1)of N),duration(0–5,>5 year),method(understory,canopy),and matter(ammonium N,nitrate N,organic N,mixed N).Results:N addition significantly increased plant N:P(leaf:14.98%,root:13.29%),plant C:P(leaf:6.8%,root:25.44%),soil N:P(13.94%),soil C:P(10.86%),microbial biomass N:P(23.58%),microbial biomass C:P(12.62%),but reduced plant C:N(leaf:6.49%,root:9.02%).Furthermore,plant C:N:P stoichiometry changed significantly under short-term N inputs,while soil and microorganisms changed drastically under high N *** N addition primarily affected plant C:N:P stoichiometry through altering plant N content,while understory N inputs altered more by influencing soil C and P *** N significantly influenced plant and soil C:N and C:P,while ammonia N changed plant N:*** C:P and soil C:N were strongly correlated with mean annual precipitation(MAT),and the C:N:P stoichiometric flexibility in soil and plant under N addition connected with soil ***,N addition decoupled the correlations between soil microorganisms and the ***:N addition significantly increased the C:P and N:P in soil,plant,and microbial biomass,reducing plant C:N,and aggravated forest P ***,these impacts were contingent on climate types,soil layers,and N input *** findings enhance our comprehension of the plant-soil system nutrient cycling mechanisms in forest ecosystems and plant strategy responses to N deposition.

关键词： C:N:P stoichiometry Meta-analysis Forest ecosystem Nitrogen addition form Nutrient cycles

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Linoleic acid alleviates mood disorders in mice by modulating microglia differentiation and arachidonic acid metabolism

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Food science and Human Wellness 2025年

作者： Meishan Lu Yanjun Liu Mengxue He Jiachen Shi Yanan Wang Xue Li Yuanfa Liu State Key Laboratory of Food Science and Technology， School of Food Science and Technology， National Engineering Research Center for Functional Food， National Engineering Laboratory for Cereal Fermentation Technology， Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province， Jiangnan University

In previous research， we demonstrated that long-term consumption of thermally oxidized oil leads to neuroinflammation and anxiety in mice. Therefore， in this study， we employed polar lipid components from thermo-induced oxidized oil to induce neurodamage. Behavioral assessments revealed that both the linoleic acid and AUDA (a classical inhibitor of soluble epoxide hydrolase) groups exhibited significantly reduced anxiety-like behaviors compared to the model group (P < 0.05). Immunofluorescence analysis indicated that microglial activation in the hippocampus was attenuated in both the linoleic acid and AUDA groups relative to the model group， accompanied by a reduction in the mRNA expression of pro-inflammatory cytokines (IL-1β， IL-6， NOS2， TNF-α) and an upregulation of neuroprotective factors (IL-4， IL-10， BDNF). Lipidomic profiling of hippocampal tissue revealed that the lipid composition of the linoleic acid group closely resembled that of the AUDA group， with a significant downregulation of cardiolipin (CL) compared to the control group， consistent with alterations in the membrane potential channel receptor TRPC1. Both linoleic acid and AUDA inhibited the mRNA expression of EPHX2， leading to an increase in EETs levels. Furthermore， linoleic acid upregulated the expression of cytochrome P450 enzymes (CYP2J6) and lipoxygenase (LOX2S)， which further upregulated the synthesis of EETs， and increased the content of 9-HODE and 13-HODE. These findings collectively suggest that linoleic acid alleviates neuroinflammation by modulating microglial differentiation and attenuates neurodegeneration induced by thermally oxidized oil through the regulation of arachidonic acid metabolism and the linoleic acid metabolic pathway， leading to the production of neuroprotective lipid mediators. Therefore， linoleic acid may serve as a potential neuro-nutrient for the treatment of anxiety disorders. This provided a scientific basis for the development of specialized medical foods aimed at

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Submarine Trenches and Wave-Wave Interactions Enhance the Sediment Resuspension Induced by Internal Solitary Waves

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Journal of Ocean University of China 2023年第4期22卷 983-992页

作者： TIAN Zhuangcai LIU Chao JIA Yonggang SONG Lei ZHANG Mingwei State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China Key Laboratory of Coastal Science and Integrated Management Ministry of Natural ResourcesQingdao266061China

Internal solitary waves(ISWs)are nonlinear fluctuations in nature that could cause significant interactions between seawater and the *** have been proven to be an adequate cause of sediment resuspension in shallow and deep-sea *** the South China Sea,ISWs have the largest amplitude globally and directly interact with the seabed near the Dongsha slope in the northern South China *** analyzed the water profile and high-resolution multibeam bathymetric data near the Dongsha slope and revealed that submarine trenches have a significant impact on the sediment resuspension by ***,ISWs in the zone of the wave-wave interaction enhanced sediment mixing and *** concentration of the suspended particulate matter inside submarine trenches was significantly higher than that outside *** concentration of the suspended particulate matter near the bottoms of trenches could be double that outside them and formed a vast bottom nepheloid *** could increase the concentration of the suspended particulate matter in the entire water column,and a water column with a high concentration of the suspended particulate matter was formed above the *** in the wave-wave interaction zone near Dongsha could induce twice the concentration of the bottom nepheloid layer than those in other *** sediment resuspension caused by ISWs is a widespread occurrence all around the *** findings of this study can offer new insights into the influence of submarine trench and wave-wave interaction on sediment resuspension and help in geohazard assessment.

关键词： sediment resuspension internal solitary waves trench wave-wave interaction

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Structural Isomers:Small Change with Big Difference in Anion Storage

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Nano-Micro Letters 2024年第1期16卷 222-234页

作者： Huichao Dai Yuan Chen Yueyue Cao Manli Fu Linnan Guan Guoqun Zhang Lei Gong Mi Tang Kun Fan Chengliang Wang School of Integrated Circuits Wuhan National Laboratory for Optoelectronics(WNLO)Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China Wenzhou Advanced Manufacturing Institute Huazhong University of Science and TechnologyWenzhou 325035People’s Republic of China Hubei Key Laboratory of Polymer Materials School of Materials Science and EngineeringHubei UniversityWuhan 430062People’s Republic of China School of Chemistry and Environmental Engineering Wuhan Institute of TechnologyWuhan 430073People’s Republic of China

Organic electrode materials are promising for ***,the reported organic electrodes are often facing the challenges of low specific capacity,low voltage,poor rate capability and vague charge storage mechanisms,*** are good platform to investigate the charge storage mechanisms and enhance the performance of batteries,which,however,have not been focused in ***,two isomers are reported for *** a result,the isomer tetrathiafulvalene(TTF)could store two monovalent anions reversibly,deriving an average discharge voltage of 1.05 V and a specific capacity of 220 mAh g−1 at a current density of 2 *** the other hand,the other isomer tetrathianaphthalene could only reversibly store one monovalent anion and upon further oxidation,it would undergo an irreversible solid-state molecular rearrangement to *** molecular rearrangement was confirmed by electrochemical performances,X-ray diffraction patterns,nuclear magnetic resonance spectra,and 1H detected heteronuclear multiple bond correlation *** results suggested the small structural change could lead to a big difference in anion storage,and we hope this work will stimulate more attention to the structural design for boosting the performance of organic batteries.

关键词： Zinc-organic batteries Isomers Solid-state molecular rearrangement Anion storage P-type organic electrode materials

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A Thruster Configuration Method for Spacecraft Six-Dimensional control 6

A Thruster Configuration Method for Spacecraft Six-Dimension...

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6th International Symposium on Autonomous Systems, ISAS 2023

作者： Wang, Min Xie, Yongchun Su, Yan National Key Laboratory of Science and Technology on Space Intelligent Control Beijing Institute of Control Engineering Beijing China

ISBN: (纸本)9798350316155

The configuration of spacecraft thrusters directly affects the realization of precise automatic control and propellant consumption. At present, the design of thruster configuration lacks of theoretical guidance. Spacecraft carrying out complex space missions such as rendezvous and docking are often equipped with too many thrusters. This paper proposed a theoretical design method of thruster configuration for six-dimensional position and attitude control missions. Firstly, the mathematical description of thruster configuration is introduced. Then, a general design method of thruster configuration for six-dimensional control task is proposed. Finally, simulation of relative position and attitude control of rendezvous and docking task is taken as an example to verify the correctness and validity of the above method. © 2023 IEEE.

关键词： Attitude control

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Analysis of the impact of long-term service of inverter devices on electromagnetic compatibility 2

Analysis of the impact of long-term service of inverter devi...

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2nd China Power Supply Society Electromagnetic Compatibility Conference, CPEMC 2024

作者： Zhang, Ruiheng Pei, Xuejun Meng, Jin Fan, Hongming Zhou, Peng Yuan, Yuzhang Power Electronics and Energy Management Key Laboratory Ministry of Education of China Huazhong University of Science and Technology Wuhan China National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan China

ISBN: (纸本)9798331509552

Taking the IGBT power module of the inverter device as the research object, finite element analysis technology was used to explore the influence of long-term service on the thermal characteristics and stress-strain of the IGBT module. At the same time, the influence of service aging on the electromagnetic compatibility performance of the device was studied, and the finite element simulation results were verified through accelerated aging experiments. The results showed that during the long-term operation of the IGBT module, due to the different thermal expansion coefficients of its materials, strain differences were found, ultimately leading to an increase in its ground capacitance, resulting in an increase in the amplitude of the common mode conducted noise of the device by 3dBμA in the frequency band after 20MHz. This study will provide theoretical guidance for the electromagnetic compatibility design of inverter devices for long-term service. ©2024 IEEE.

关键词： Insulated gate bipolar transistors (IGBT)

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Observation of multiple surface states in naturally cleavable chiral crystal PdSbSe

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Physical Review Materials 2025年第3期9卷 L031201-L031201页

作者： Zhicheng Jiang Zhengtai Liu Chenqiang Hua Xiangqi Liu Yichen Yang Jianyang Ding Jiayu Liu Jishan Liu Mao Ye Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201210 China National Synchrotron Radiation Laboratory and School of Nuclear Science and Technology University of Science and Technology of China Hefei 230026 China National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information Technology (SIMIT) Chinese Academy of Sciences Shanghai 200050 China Zhejiang Province Key Laboratory of Quantum Technology and Device Department of Physics Zhejiang University Hangzhou 310027 China State Key Lab of Silicon Materials School of Materials Science and Engineering Zhejiang University Hangzhou 310027 China Beihang Hangzhou Innovation Institute Yuhang Xixi Octagon City Yuhang District Hangzhou 310023 China School of Physical Science and Technology ShanghaiTech University Shanghai 200031 China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

Chiral multifold fermions in solids exhibit unique band structures and topological properties, making them ideal for exploring fundamental physical phenomena related to nontrivial topology, chirality, and symmetry breaking. However, the challenge of obtaining clean, flat surfaces through cleavage has hindered the investigation of their unique electronic states. In this study, we utilize high-resolution angle-resolved photoemission spectroscopy and density functional theory calculations to investigate the low-energy electronic structure of the cleavable single-crystal PdSbSe. Our combined experimental and theoretical analysis reveals the presence of multifold-degenerate fermions within this chiral crystal. We also observe multiple chiral Fermi arc surface states and spin-splitting behavior in the associated bulk bands. These findings provide unique insights into chiral, multifold fermionic states in easily cleavable crystals and offer a robust platform for further research into their unique electronic properties and potential applications in novel electronic devices.

关键词： Photoelectron spectroscopy

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