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Chinese Journal of Aeronautics 2025年第1期38卷 551-567页

作者： jin liu Huanzi ZHANG Xiaolin NING Xin MA School of Electronic Information Wuhan University of Science and TechnologyWuhan 430081China School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China Hefei National Laboratory Hefei 230088China

The traditional orbit determination method based on pulsar profile distortion can determine the six elements of the ***,the estimation accuracies of these methods are limited and the computational load of a six-dimensional search is *** solve this problem,the differential-geometry-based Multi-dimensional Joint Position-Velocity Estimation(MJPVE)using Crab pulsar profile distortion is proposed in this ***,through theoretical analysis,it is found that the pulsar profile distortion caused by the initial state error in some joint positionvelocity directions is very *** other words,the accuracies of estimation in these directions are very ***,the search dimension can be reduced,which in turn greatly reduces the computational ***,we construct the chi-squared function of the pulsar profile with respect to the estimation error in joint position-velocity direction and use differential geometry to find the joint position-velocity directions corresponding to different degrees of ***,we utilize the grid search based on directory folding in these joint position-velocity directions corresponding to large degrees of distortion to obtain the joint position-velocity *** experimental results show that compared with the grouping bi-chi-squared inversion method,MJPVE has high precision and extensive navigation information.

关键词： Joint Position-Velocity Estimation Pulsars Profile Distortion Orbit Determination Differential Geometry

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Efficient implementation of quantum permutation algorithm using a polar SrO molecule in pendular states

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Communications in Theoretical Physics 2025年第2期77卷 41-53页

作者： Jie-Ru Hu Zuo-Yuan Zhang jin-Ming liu State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University School of Physical Science and Technology Yangzhou University Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal University

Quantum algorithms offer more enhanced computational efficiency in comparison to their classical counterparts when solving specific tasks. In this study, we implement the quantum permutation algorithm utilizing a polar molecule within an external electric field. The selection of the molecular qutrit involves the utilization of field-dressed states generated through the pendular modes of SrO. Through the application of multi-target optimal control theory, we strategically design microwave pulses to execute logical operations, including Fourier transform,oracle Ufoperation, and inverse Fourier transform within a three-level molecular qutrit *** observed high fidelity of our outcomes is intricately linked to the concept of the quantum speed limit, which quantifies the maximum speed of quantum state manipulation. Subsequently,we design the optimized pulse sequence to successfully simulate the quantum permutation algorithm on a single SrO molecule, achieving remarkable fidelity. Consequently, a quantum circuit comprising a single qutrit suffices to determine permutation parity with just a single function evaluation. Therefore, our results indicate that the optimal control theory can be well applied to the quantum computation of polar molecular systems.

关键词： polar molecule optimal control quantum permutation algorithm pendular states

Spatial transcriptomics combined with single-nucleus RNA sequencing reveals glial cell heterogeneity in the human spinal cord

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Neural Regeneration Research 2025年第11期20卷 3302-3316页

作者： Yali Chen Yiyong Wei jin liu Tao Zhu Cheng Zhou Donghang Zhang Department of Anesthesiology West China HospitalSichuan UniversityChengduSichuan ProvinceChina Laboratory of Anesthesia and Critical Care Medicine National-Local Joint Engineering Research Center of Translational Medicine of AnesthesiologyWest China HospitalSichuan UniversityChengduSichuan ProvinceChina Department of Anesthesiology Longgang District Maternity&Child Healthcare Hospital of Shenzhen City(Longgang Maternity and Child Institute of Shantou University Medical College)ShenzhenGuangdong ProvinceChina Department of Anesthesiology Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou ProvinceChina

Glial cells play crucial roles in regulating physiological and pathological functions,including sensation,the response to infection and acute injury,and chronic neurodegenerative *** cells include astrocytes,microglia,and oligodendrocytes in the central nervous system,and satellite glial cells and Schwann cells in the peripheral nervous *** the greater understanding of glial cell types and functional heterogeneity achieved through single-cell and single-nucleus RNA sequencing in animal models,few studies have investigated the transcriptomic profiles of glial cells in the human spinal ***,we used high-throughput single-nucleus RNA sequencing and spatial transcriptomics to map the cellular and molecular heterogeneity of astrocytes,microglia,and oligodendrocytes in the human spinal *** explore the conservation and divergence across species,we compared these findings with those from *** the human spinal cord,astrocytes,microglia,and oligodendrocytes were each divided into six distinct transcriptomic *** the mouse spinal cord,astrocytes,microglia,and oligodendrocytes were divided into five,four,and five distinct transcriptomic subclusters,*** comparative results revealed substantial heterogeneity in all glial cell types between humans and ***,we detected sex differences in gene expression in human spinal cord glial ***,in all astrocyte subtypes,the levels of NEAT1 and CHI3L1 were higher in males than in females,whereas the levels of CST3 were lower in males than in *** all microglial subtypes,all differentially expressed genes were located on the sex *** addition to sex-specific gene differences,the levels of MT-ND4,MT2A,MT-ATP6,MT-CO3,MT-ND2,MT-ND3,and MT-CO_(2) in all spinal cord oligodendrocyte subtypes were higher in females than in ***,the present dataset extensively characterizes glial cell heterogeneity and offers a valuable resource for explo

关键词： astrocyte glial cell human microglia oligodendrocyte sex differentiation single-nucleus RNA sequencing spatial transcriptomics species variation spinal cord

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Impact of warming and nitrogen addition on soil greenhouse gas fluxes:A global perspective

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Journal of Environmental Sciences 2025年第5期151卷 88-99页

作者： Hongze Ma Xiaoyu Jia Weiguang Chen jingyi Yang jin liu Xiaoshan Zhang Ke Cui Zhouping Shangguan Weiming Yan State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau College of Soil and Water Conservation Science and EngineeringNorthwest A&F UniversityYanglingShaanxi 712100China Institute of Soil and Water Conservation Chinese Academy of SciencesYanglingShaanxi 712100China University of Chinese Academy of Sciences Beijing 100049China Shaanxi Institute of Geo-Environment Monitoring Xi’an 710000China

Global warming and nitrogen(N)deposition have a profound impact on greenhouse gas(GHG)fluxes and consequently,they also affect climate ***,the global combined effects of warming and N addition on GHG fluxes remain to be fully *** address this knowledge gap,a globalmeta-analysis of 197 datasets was performed to assess the response of GHG fluxes to warming and N addition and their interactions under various climate and experimental *** results indicate that warming significantly increased CO_(2)emissions,while N addition and the combined warming and N addition treatments had no impact on CO_(2)***,both warming and N addition and their interactions exhibited positive effects on N_(2)O *** the combined warming and N addition treatments,warming was observed to exert a positive main effect on CO_(2)emissions,while N addition had a positive main effect on N_(2)O *** interactive effects of warming and N addition exhibited antagonistic effects on CO_(2),N_(2)O,and CH_(4)emissions,with CH_(4)uptake dominated by additive ***,we identified biome and climate factors as the two *** findings indicate that both warming and N addition substantially impact soil GHG fluxes and highlight the urgent need to investigate the influence of the combination of warming and N addition on terrestrial carbon and N cycling under ongoing global change.

关键词： Warming Nitrogen(N)addition Greenhouse gas(GHG)fluxes Interactive effects Biome

Improved oxygen electrocatalysis at Fe N4 and Co N4 sites via construction of axial coordination

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Chinese Chemical Letters 2025年第2期36卷 482-487页

作者： Ze Zhang Lei Yang jin-Ru liu Hao Hu Jian-Li Mi Chao Su Bei-Bei Xiao Zhi-Min Ao School of Energy and Power Engineering Jiangsu University of Science and Technology Institute for Computation in Molecular and Materials Science School of Chemistry and Chemical Engineering Nanjing University of Science and Technology Institute for Advanced Materials School of Materials Science and Engineering Jiangsu University Advanced Interdisciplinary Institute of Environment and Ecology Beijing Normal University

The quest for efficient and durable catalysts using abundant resources has garnered significant interest in the field of bifunctional oxygen *** this contribution,we have designed a FeN4or CoN4embedded graphene-based bilayer as active layer and TMC3or TMN3doped graphene as supporting layer,named as FeN4/TMC3or FeN4/TMN3and CoN4/TMC3or CoN4/TMN3,wherein TM strands for transition *** on density functional theory calculations,our results demonstrate that the interaction formed between dual metal atoms in the bilayer interspace leads to the coordination environment altered from flat four-coordination to spatial five-coordination,further stabilizing the bilayer structure and impairing its affinity toward the O-containing *** to thermodynamic analysis,the bilayers of CoN4/CoN3,FeN4/FeC3,FeN4/CoC3,FeN4/NiC3,FeN4/ZnC3,FeN4/FeN3,FeN4/CrN3and FeN4/ZnN3are attractively promising for bifunctional oxygen electrocatalysis due to the small overpotential differenceΔη between oxygen reduction and oxygen evolution that are less than 1 *** functional theory calculations combined with machine learning analysis directly identify the key role played by the interbinding formed between bilayers,that boosts catalytic activity,which establishes a predictable framework for a fast screen for graphene-based bilayer vertical *** work opens up a new path for designing the efficient electrocatalysts via modification of coordination environment.

关键词： Density functional theory Machine learning Oxygen electrocatalysis Thermodynamic analysis

Preliminary Design of a System for Picking up Audio-Signals From Bubble Detectors GAO Si-ze1,NI Bang-fa,ZHANG Gui-ying,XIAO Cai-jin,liu Cun-xiong, CHEN Zhe1,NIE Peng,liu Chao1,ZHAO Chang-jun (*** of Physics Science and Engineering Technology,Guang

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Preliminary Design of a System for Picking up Audio-Signals ...

Tuning the porosity of {Co12IICo8III（μ3-OH）24（X）}11+ supramolecular frameworks by reaction time for D2/H2 separation

作者： GAO Si-ze NI Bang-fa ZHANG Gui-ying XIAO Cai-jin liu Cun-xiong CHEN Zhe NIE Peng liu Chao ZHAO Chang-jun College of Physics Science and Engineering Technology Guangxi University

This system is designed to pick up sound signals from large volume,low-threshold energy, low-background superheated droplets bubble detectors.A sound-sensitive bubble detector is composed of a container filled with a mixture of superheated droplets and gel,a temperature and pressure control system,and an audio acquisition system attached on the outer surface of the *** superheated droplets are in a metastable and superheated state at ambient temperature and *** the outside

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Science China Chemistry 2025年

作者： Zhuozhou Xie Zhu Zhuo Zi-Ang Nan Qing Li Xiufang Li Zi-Xiu Lu Linzhe Lü jin liu Luyao liu Wenjing Wang Wei Wang Daqiang Yuan You-Gui Huang State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/H2separation （～3?）.Here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8L12（μ3-OH）24（X）]1clusters （L=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8L12（μ3-OH）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-OH）24（ClO4）L12)]·（Cl）4·（HCO2）7（1）,[CoII12CoIII8L12（μ3-OH）24（Cl）]·（ClOI4）4·（Cl）6·（HCO2）·（H2O）10（2）,and[CoI12CoIII8L12（μ3-OH）24（Cl）]·（Cl）11·（H2O）12（3）.The different stacking patterns of the[CoII12CoIII8L12（μ3-OH）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than H2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/H2separation at 77 K (retention time:～7 min/g for D2/H2/Ne （10/10/80 vol%） in a flow of 5 mL

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基于异构扩散模型的输油管道缺陷及组件检测方法

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控制与决策 2025年第03期40卷 937-945页

作者：神祥凯刘金海东北大学信息科学与工程学院

高精度的缺陷检测和组件检测对确保管道的安全运行至关重要.针对现有检测方法存在精度低和泛化性差的难题,提出一种基于异构扩散模型的新型管道缺陷和组件检测方法.首先,将原始的漏磁信号预处理以降低信号采集中噪声等负面因素的影响;其... 详细信息

高精度的缺陷检测和组件检测对确保管道的安全运行至关重要.针对现有检测方法存在精度低和泛化性差的难题,提出一种基于异构扩散模型的新型管道缺陷和组件检测方法.首先,将原始的漏磁信号预处理以降低信号采集中噪声等负面因素的影响;其次,针对特征提取困难的问题,设计一种基于稀疏注意力模块的特征提取方法,通过稀疏化的方式建立漏磁信号间的长距离依赖关系,进而实现模型对缺陷和组件的信息聚焦;此外,将传统的特征金字塔网络替换为路径聚合特征金字塔网络,充分确保多尺度特征的完备性;最后,设计一种基于异构扩散模型的检测机制,将候选框回归过程转换为随机框的去噪过程,减少模型对预先设定的锚点的依赖,进而提升模型的泛化性和准确性.基于实际管道对其有效性进行验证,实验结果表明,所提出方法的平均检测精度达到97.4%,优于最先进的对比方法 3.5%,确保了其在应用中的前景.

关键词：漏磁检测管道缺陷检测管道组件检测卷积神经网络注意力机制扩散模型

低温下玄武岩纤维混凝土劈拉强度尺寸效应试验

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哈尔滨工业大学学报 2025年第1期57卷 101-109页

作者：余文轩范美妤金浏杜修力清华大学土木水利学院北京100084 城市减灾与防灾防护教育部重点实验室(北京工业大学) 北京100124

为研究极端低温作用下结构尺寸和纤维体积分数对玄武岩纤维混凝土劈拉强度的定量影响规律和作用机制,设计了4种尺寸(边长分别为70、100、150和200 mm)、4种纤维体积分数(分数范围0%~0.5%)的玄武岩纤维混凝土立方体试块在常温和低温下(... 详细信息

为研究极端低温作用下结构尺寸和纤维体积分数对玄武岩纤维混凝土劈拉强度的定量影响规律和作用机制,设计了4种尺寸(边长分别为70、100、150和200 mm)、4种纤维体积分数(分数范围0%~0.5%)的玄武岩纤维混凝土立方体试块在常温和低温下(温度范围20~-90℃)进行了静态劈拉破坏试验。试验结果表明:不同类型混凝土的劈拉强度均随温度降低而线性增大(最大增幅接近130%),呈现出显著的低温增强效应;玄武岩纤维的掺入能略微强化混凝土劈拉强度的低温增强效应。不同纤维体积分数玄武岩纤维混凝土的劈拉强度均呈现出一定的纤维增强效应,并且随体积分数增加而增强;极端低温作用下玄武岩纤维的主导破坏模式由拔出破坏转变为拉断破坏,导致纤维增强效应随温度下降而变强。劈拉强度的尺寸效应随温度下降而更明显,但玄武岩纤维的掺入能减弱尺寸效应(最大削弱程度达25.8%)。本文研究能为玄武岩纤维混凝土材料在极端低温环境下的大规模工程结构应用提供有效参考。

关键词：玄武岩纤维混凝土极端低温纤维含量劈裂拉伸尺寸效应

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基于轨迹集的衍生扩展目标多伯努利滤波算法

控制与决策 2025年第03期40卷 1024-1034页

作者：杨英壮蔡如华吴孙勇刘锦新桂林电子科技大学数学与计算科学学院桂林电子科技大学广西精密导航技术与应用实验室

针对扩展目标多伯努利滤波器(ECBMeMBer)在复杂环境下对衍生扩展目标跟踪性能严重下降以及无法提取目标轨迹的问题,提出一种基于轨迹随机有限集(Trajectory RFS)的衍生扩展目标多伯努利滤波算法(STCBMeMBer).首先,利用轨迹多伯努利RFS(T... 详细信息

针对扩展目标多伯努利滤波器(ECBMeMBer)在复杂环境下对衍生扩展目标跟踪性能严重下降以及无法提取目标轨迹的问题,提出一种基于轨迹随机有限集(Trajectory RFS)的衍生扩展目标多伯努利滤波算法(STCBMeMBer).首先,利用轨迹多伯努利RFS(Trajectory MBer-RFS)描述多扩展目标的轨迹序列,从而为扩展目标提供连续的轨迹信息;其次,提出一种多伯努利衍生模型,通过原始扩展目标的航向角与衍生扩展目标的偏转角之间的三角函数关系式建立不同衍生扩展目标的运动方程与动力学转移模型,从而实现对衍生扩展目标质心状态与外形状态的联合估计;随后,基于轨迹MBer-RFS和所提出的多伯努利衍生模型推导并提出S-TCBMeMBer滤波器,并在线性高斯条件下给出伽玛高斯逆威沙特(GGIW)混合实现.仿真结果表明,所提出算法在杂波、漏检和噪声共存的环境下能够对衍生扩展目标进行有效跟踪,并提取扩展目标完整的轨迹信息.

关键词：轨迹随机有限集衍生扩展目标多伯努利航向角偏转角伽玛高斯逆威沙特