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A guidance and control design with reduced information for a dual-spin stabilized projectile

Defence Technology（防务技术） 2024年第3期33卷 494-505页

作者： yu Wang Jiyan yu Xiaoming Wang Jia Fangxiu Intelligent Ammunition Technology National Defense Key Discipline Laboratory Nanjing University of Science and TechnologyNanjingJiangsu210094China

In this paper,an integrated guidance and control method based on an adaptive path-following controller is proposed to control a spin-stabilized projectile with only translational motion information under the constraint of an actuator,uncertainties in aerodynamic parameters and measurements,and control system *** to the fairly high rotation speed,the dynamic model of this missile is strongly nonlinear,uncertain and coupled in pitch,yaw and roll channels.A theoretical equivalent resultant force and uncertainty compensation method are comprehensively used to realize decoupling of pitch and *** response to the strong nonlinear and time-varying characteristics of the dynamic system,the quasi-linear model whose parameters are obtained by interpolation of points selected as the segmentation points in the trajectory envelope,is used for calculation in each *** cope with the system uncertainty caused by model approximation,parameter uncertainty and ballistic interference,an extended state estimator is used to compensate the output feedback according to the test ballistic *** order to improve the tracking efficiency and ensure the tracking error convergence with only translational motion information,the virtual guide point,whose derivative is deduced according to the Lyapunov principle,is calculated in real time according to the projection relationship between the real-time position and the reference trajectory,and a virtual line-of-sight angle and the backstepping method are used for the design of the guidance and control *** order to avoid the influence of control input saturation on the guidance and control performance due to the actuator limitation and improve the robustness of the system,an anti-saturation compensator is designed according to the two-step *** feasibility and effectiveness of the path-following controller is verified through closed-loop flight simulations with measurement,control,and condition *** result

关键词： Spin-stabilized projectile Reduced information Path-following control Extended state observer Coupled nonlinear system Input saturation

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城镇搬迁地土壤厚度划分与案例研究

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土壤 2021年第5期53卷 1081-1086页

作者：于全波张浪黄绍敏梁晶韩继刚王小涵上海市园林科学规划研究院上海200232 上海城市困难立地绿化工程技术研究中心上海200232 河南农科院植物营养与环境研究所郑州450000

为确定城镇搬迁地绿化有效土壤厚度,通过对比城镇搬迁地原地土壤和传统农业土壤的差异,基于土壤、杂填土、建筑垃圾和土体等基本概念,对城镇搬迁地土壤厚度进行了定义;基于建筑垃圾层位置和园林绿化种植土相关标准定义了城镇搬迁地绿化... 详细信息

为确定城镇搬迁地绿化有效土壤厚度,通过对比城镇搬迁地原地土壤和传统农业土壤的差异,基于土壤、杂填土、建筑垃圾和土体等基本概念,对城镇搬迁地土壤厚度进行了定义;基于建筑垃圾层位置和园林绿化种植土相关标准定义了城镇搬迁地绿化有效土壤厚度的内涵;并以上海市世博文化园和三林楔形绿地建成前城镇搬迁地为例进行了土壤厚度划分方法的应用。结果表明:城镇搬迁地土壤厚度是城镇搬迁地内土壤剖面所有的土壤物质层厚度之和;城镇搬迁地绿化有效厚度为在城镇搬迁地中位于地下水之上、自身理化性质符合或者经过改良后符合地方规定的园林绿化种植土标准的土壤物质层厚度。上海市世博文化园建成前城镇搬迁地土壤厚度为2.4~4.5 m,但由于土壤理化性质不符合园林绿化用土标准,绿化有效土厚为零,绿化种植土均需采用客土。三林楔形绿地建成前城镇搬迁地土壤厚度大于1 m,土壤经过改良均可作为园林绿化种植土。但由于地下水层的存在,城镇搬迁地绿化有效土厚为1 m。因此,城镇搬迁地绿化有效土壤厚度划分方法可为城镇搬迁地原地土壤和客土用量的快速估算提供科学依据。

关键词：城镇搬迁地土壤厚度绿化土壤有效土厚划分标准

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A Note on the Entropy for Heisenberg Group Actions on the Torus

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2324-2336页

作者： yu ZHANG yu Jun ZHU School of Mathematical Sciences Xiamen University

In this paper,the entropy of discrete Heisenberg group actions is *** α be a discrete Heisenberg group action on a compact metric space *** types of entropies,■ and h(α)are introduced,in which ■ is defined in Ruelle’s way and h(α) is defined via the natural extension of α.It is shown that when X is the torus and α is induced by integer matrices then ■ is zero and h(α) can be expressed via the eigenvalues of the matrices.

关键词： Entropy Heisenberg group action natural extension torus

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Silicon dioxide-protection boosting the peroxidase-like activity of Fe single-atom catalyst for combining chemo-photothermal therapy

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Nano Research 2024年第6期17卷 4924-4933页

作者： yu Fan yu Yi Hongpan Rong Jiatao Zhang Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China CAS Center for Excellence in Nanoscience CAS KeyLaboratory for Biomedical Effects of Nanomaterials and NanosafetyNational Center for Nanoscience and Technology(NCNST)Beijing 100190China Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering Ministry of Industry and Information TechnologySchool of Chemistry&Chemical EngineeringBeijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green ApplicationsSchool of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

Carbon-based single-atom catalysts(SACs)have been widely studied in the field of biomedicine due to their excellent catalytic ***,carbon-based SACs usually aggregate during pyrolysis,which leads to the reduction of catalytic ***,we describe a method to improve the monodispersion of SACs using silicon dioxide as a protective *** decoration of silicon dioxide serves as a buffer layer for individual nanoparticles,which is not destroyed during the pyrolysis process,ensuring the single-particle dispersion of the nanoparticles after *** approach increased the hydroxyl groups on the surface of Fe-SAC(Fe-SAC-SE)and improved its water solubility,resulting in a four times enhancement of the peroxidase(POD)-like activity of Fe-SAC-SE(58.4 U/mg)than that of non-protected SACs(13.9 U/mg).The SiO_(2)-protection approach could also improve the catalytic activities of SACs with other metals such as Mn,Co,Ni,and Cu,indicating its generality for SACs *** advantage of the high POD-like activity,photothermal properties,and large specific surface area of Fe-SAC-SE,we constructed a synergistic therapeutic system(Fe-SAC-SE@DOX@PEG)for combining the photothermal therapy,catalytic therapy,and *** was verified that the photothermal properties of Fe-SAC-SE@DOX@PEG could effectively improve its POD-like activity,exhibiting excellent tumor-killing performance at the cellular *** work may provide a general approach to improve the performances of SACs for disease therapy and diagnosis.

关键词： single-atom catalysts peroxidase-like activity SiO2-protection photothermal therapy catalytic therapy chemotherapy

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U-Pb zircon geochronology of basaltic pyroclastic rocks from the basement beneath the Xisha Islands in the northwestern South China Sea and its geological significance

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Acta Oceanologica Sinica 2024年第2期43卷 83-93页

作者： yu Zhang Kefu yu Shiying Li Guangxi Laboratory on the Study of Coral Reefs in the South China Sea Guangxi UniversityNanning 530004China Coral Reef Research Center of China Guangxi UniversityNanning 530004China School of Marine Sciences Guangxi UniversityNanning 530004China Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of ScienceGuangzhou 510301China

As one of the micro-blocks dispersed in the South China Sea(SCS), the basement of the Xisha Islands has rarely been drilled because of the thick overlying Cenozoic sediments, which has led to a confused understanding of the pre-Cenozoic basement of the Xisha Islands. Well CK-1, a kilometer-scale major scientific drill in the Xisha Islands in the northwestern SCS, penetrated thick reefal limestone(0–888.4 m) and the underlying basement rocks(888.4–901.4 m). In this study, we present the zircon U-Pb ages of basement basaltic pyroclastic rocks from Well CK-1 in the Xisha Islands of the northwestern SCS to investigate the basement nature of the Xisha microblock. The basement of Well CK-1 consists of basaltic pyroclastic rocks on the seamount. The zircon grains yielded apparent ages ranging from ca. 2 138.9 Ma to ca. 36 Ma. The old group of zircon grains from Well CK-1 was considered to be inherited zircons. Two Cenozoic zircons gave a weighted mean 206Pb/238U age of(36.3 ± 1.1) Ma,Mean Squared Weighted Deviations(MSWD) = 1.2, which may represent the maximum age of the volcano eruption. The Yanshanian inherited zircons(116.9–105.7 Ma and 146.1–130.2 Ma) from Well CK-1 are consistent with the zircons from Well XK-1, indicating that the basement of Chenhang Island may be similar to that of Well XK-1. We propose that the Xisha micro-block may have developed on a uniform Late Jurassic metamorphic crystalline basement, intruded by Cretaceous granitic magma.

关键词： South China Sea Xisha Islands basaltic pyroclastic rocks zircon

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Quantum Spin Exchange Interactions to Accelerate the Redox Kinetics 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 Kai Guo Gan Qu Jianan Zhang Key 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

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Study on viscosity mechanism of caffeine crystallization solutions Author links open overlay panel

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Particuology 2024年第8期91卷 341-350页

作者： Linjing yu Min Su School of Chemical Engineering Hebei University of TechnologyTianjin300130China

The solid-liquid viscous system formed by high viscosity crystallization solution impacts the flow and separation ***,it is very important to study the viscosity mechanism to improve viscosity and regulate crystallization,ensuring a seamless production ***,the viscosity of crystallization solution was taken as the measurement parameter of caffeine as a model *** investigated the viscosity mechanism of caffeine crystallization solutions by combining experiment and *** results indicated that the weak interactions between caffeine and water result in increased viscosity of the caffeine crystallization ***,caffeine crystals possess elongated needle-like shapes,featuring a substantial specific surface ***,there isπ-πstacking occurring between the(200)crystal face and(110)crystal face,effectively fostering coalescence of the crystals towards the radial side of the crystal along its elongated axis,resulting in a more viscous crystallization *** results contribute to comprehending the viscosity mechanism of crystal systems and provide theoretical foundation to enhance engineering efficiency in crystallization.

关键词： Crystallization Caffeine Viscosity mechanism Molecular simulation

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Light People:Professor Laura Na Liu

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Light(Science & Applications) 2024年第2期13卷 184-189页

作者： Hui Wang Cun yu Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences130033ChangchunChina

Editorial The DNA nanotechnology outlines a new chapter in biological sciences,opening a new era of scientific and technological advancements.A pioneer of DNA nanotechnology,Professor Liu from the University of Stuttgart in Germany,our latest Light People,has been working at the interface,where nanophotonics meets biology and *** the path of scientific explorations.

关键词： chemistry. advancement pioneer

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Microscopic ensemble bootstrap in phase space

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Communications in Theoretical Physics 2024年第6期76卷 72-76页

作者： yu Zhang College of Mechanics and Engineering Science Hohai UniversityNanjing 211100China

The bootstrap method which has been studied under many quantum mechanical models turns out to be feasible in microcanonical ensembles as *** the approach of Nakayama(2022 ***.A 372250054)produces a sector when energy is negative,in this paper we report a method that has stronger constraints and results in a smaller *** also study other models to demonstrate the effectiveness of our method.

关键词： numerical bootstrap microcanonical ensemble Poisson bracket bootstrap oscillator

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Comprehensive Assessment of STGSA Generated Skeletal Mechanism for the Application in Flame-Wall Interaction and Flame-Flow Interaction

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Journal of Thermal Science 2024年第5期33卷 1946-1960页

作者： yu Chunkan YANG Bin Institute of Technical Thermodynamics Karlsruhe Institute of TechnologyKarlsruhe 76131Germany Center for Combustion Energy Tsinghua UniversityBeijing 100084China

In this study,we conduct a thorough evaluation of the STGSA-generated skeletal mechanism for C_(2)H_4/*** STGSA-reduced mechanisms are taken into account,incorporating basic combustion models such as the homogeneous reactor model,one-dimensional flat premixed flame,and non-premixed counterflow ***,these models are applied to more complex combustion systems,considering factors like flame-flow interaction and flame-wall *** considerations take into account additional physical parameters and processes such as mixing frequency and *** results indicate that the skeletal mechanism adeptly captures the behavior of these complex combustion ***,it is suggested to incorporate strain rate considerations in generating the skeletal mechanism,especially when the combustion system operates under high turbulent intensity.

关键词： Species-Targeted Global Sensitivity Analysis(STGSA) mechanism reduction Partially Stirred Reactor(PaSR) spark ignition Head-on Quenching(HoQ)

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