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Disturbance Observer-based Pointing Control of Leighton Chajnantor Telescope

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Research in Astronomy and Astrophysics 2024年第1期24卷 135-150页

作者： Weirui Chen zheng wang school of Automation Southeast UniversityNanjing 210096China Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationSoutheast UniversityNanjing 210096China

Leighton Chajnantor Telescope(LCT), i.e., the former Caltech Submillimeter Observatory telescope, will be refurbished at the new site in Chajnantor Plateau, Chile in 2.2.. The environment of LCT will change significantly after its relocation, and the telescope will be exposed to large wind disturbances directly because its enclosure will be completely open during observation. The wind disturbance is expected to be a challenge for LCT's pointing control since the existing control method cannot reject this disturbance very well. Therefore, it is very necessary to develop a new pointing control method with good capability of disturbance rejection. In this research, a disturbance observer—based composite position controller(DOB-CPC) is designed, in which an H∞feedback controller is employed to compress the disturbance, and a feedforward linear quadratic regulator is employed to compensate the disturbance precisely based on the estimated disturbance signal. Moreover, a controller switching policy is adopted, which applies the proportional controller to the transient process to achieve a quick response and applies the DOB-CPC to the steady state to achieve a small position error. Numerical experiments are conducted to verify the good performance of the proposed pointing controller(i.e., DOB-CPC) for rejecting the disturbance acting on LCT.

关键词： instrumentation:miscellaneous methods:analytical methods:numerical telescopes

Highly efficient and photothermally stable CDs@ZIF-8 for laser illumination

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Chinese Chemical Letters 2024年第10期35卷 273-277页

作者： Zhi wang Lingpeng Yan Yelin Hao Jingxia zheng Yongzhen {2. Xuguang Liu Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

Carbon dots(CDs),as a solid-state phosphor,have great potential for application in a new solid-state lighting device—laser diode(LD).For high efficiency LD devices,both high photoluminescence quantum yield(PLQY)and high photothermal stability of CDs are ***,yellow CDs@ZIF-8 composites with high structural stability were prepared by encapsulating CDs in zeolitic imidazolate framework-8(ZIF-8)through electrostatic adsorption between CDs and ZIF-8,in which CDs with amino groups on the surface were used as luminescent feeders and ZIF-8 was used as a protective layer *** asprepared CDs@ZIF-8 not only possess a high PLQY of up to 81.17%,but also maintain a high fluorescence intensity of 100%and 80%under long-term illumination(60 min)and high temperature(478 K),*** hydrogen bonding between CDs and ZIF-8 in the encapsulated structure can enhance the degree of electron cloud delocalization,which can improve the PLQY of CDs@***,CDs@ZIF-8has high photothermal stability due to the binding effect of ZIF-8 on CDs and high thermal stability of *** white LD device,fabricated from CDs@ZIF-8 as a phosphor in combination with 450 nm blue LD,has a color coordinate of(0.37,0.33),a color temperature of 3762.K,and a high color rendering index of *** study provides a new strategy for the construction of solid-state phosphors with high PLQY and high photothermal performance.

关键词： Carbon dots Metal-organic frameworks High photothermal stability High photoluminescence quantum yield Laser illumination

Efficient production of ligand-free microscintillators at gram-scale for high-resolution X-ray luminescence imaging

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Chinese Chemical Letters 2024年第3期35卷 554-558页

作者： Hao Jiang Qihao Chen Hongyu wang Tingting Wu Jianwei Gong Zhenzhen Zhang Qiushui Chen Huanghao yang {2. Xie New Cornerstone Science Laboratory MOE Key Laboratory for Analytical Science of Food Safety and BiologyCollege of ChemistryFuzhou UniversityFuzhou 350108China school of Public Health Fujian Medical UniversityFuzhou 350108China Joint school of National University of Singapore and Tianjin University Fuzhou International Campus of Tianjin UniversityFuzhou 350207China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The efficient production of high-quality scintillators with long radioluminescence afterglow is crucial for high-performance X-ray luminescence extension ***,scaling-up the synthesis of ligand-free scintillators to fabricate large-area X-ray imaging screens for industrial applications remains a *** this study,we report an efficient method to synthesize ligand-free,lanthanide-doped microscintillators by a one-pot reaction via the concentrated hydrothermal *** as-synthesized microscintillators exhibit prolonged persistent radioluminescence for up to 30 days after X-ray exposure and remain high stability in air or water for more than 18 months without *** Carlo simulations indicate that the size effect is responsible for the excellent afterglow performance of the *** employ these high-quality lanthanide-doped microscintillators to fabricate a large-area X-ray imaging detector using a blade-coating method,a spatial resolution of 2..9 lp/mm for X-ray *** study offers a solution for scaling-up the synthesis of low-cost microscintillators for practical applications.

关键词： Microscintillators NaLuF_(4):Tb^(3+) Afterglow X-ray detector X-ray luminescence imaging

Revolutionizing plasmonic platform via magnetic field-assisted confined ultrafast laser deposition of high-density,uniform,and ultrafine nanoparticle arrays

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International Journal of Extreme Manufacturing 2024年第3期6卷 428-438页

作者： Jin Xu Lingfeng wang Peilin yang Haoqing Jiang Huai {2. Licong An Xingtao Liu Gary J Cheng school of Industrial Engineering Purdue UniversityWest LafayetteIN 47906United States of America Institute of Technological Sciences Wuhan UniversityWuhanHubei 430072People’s Republic of China

The remarkable capabilities of 2. plasmonic surfaces in controlling optical waves havegarnered significant ***,the challenge of large-scale manufacturing of uniform,well-aligned,and tunable plasmonic surfaces has hindered their *** address this,we present a groundbreaking tunable plasmonic platform design achieved throughmagnetic field(MF)assisted ultrafast laser direct deposition in *** precise control of metal nanoparticles(NPs),with cobalt(Co)serving as the model material,employing an MF,and fine-tuning ultrafast laser parameters,we have effectively converted coarse and non-uniform NPs into densely packed,uniform,and ultrafine NPs(~3 nm).This revolutionary advancement results in the creation of customizable plasmonic‘hot spots,’which play a pivotal role insurface-enhanced Raman spectroscopy(SERS)*** profound impact of this designable plasmonic platform lies in its close association with plasmonic resonance and *** the plasmonic nanostructures resonate with incident light,they generate intense local electromagnetic fields,thus vastly increasing the Raman scattering *** enhancement leads to an outstanding 2.18 fold boost in SERS performance and unparalleled sensing sensitivity down to 10^(-10)***,the plasmonic platform also demonstratesrobustness,retaining its sensing capability even after undergoing 50 cycles of rinsing andre-loading of ***,this work adheres to green manufacturing standards,making it an efficient and environmentally friendly method for customizing plasmonic‘hot spots’inSERS *** study not only achieves the formation of high-density,uniform,and ultrafine NP arrays on a tunable plasmonic platform but also showcases the profound relation betweenplasmonic resonance and energy *** outstanding results observed in SERS sensors further emphasize the immense potential of this technology for energy-relatedapplications,including photocatalysis,ph

关键词： magnetic field manipulation laser deposition metasurface SERS

Theoretical and experimental design in the study of sulfide-based solid-state battery and interfaces

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Chinese Chemical Letters 2024年第2期35卷 242-251页

作者： Hongjie Xu Yujie Su Chenggong zheng Yuchen wang Yuping Tong Zhongzheng yang Junhua Hu school of Materials Science and Engineering North China University of Water Resources and Electric PowerZhengzhou 450046China school of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Titanium Based Advanced Materials Industrial Research Institute Jiaozuo 454191China

In recent years,due to the increasing demand for portable electronic devices,rechargeable solid-state battery technology has developed ***-ion batteries are the systems of choice,offering high energy density,flexible and lightweight design,and longer lifespan than comparable battery ***,a better understanding of the relationship between electrochemical mechanism and structural properties from theory and experiment will enable us to accelerate the development of high-performance and security *** review discusses the interplay between theoretical calculation and experiment in the study of lithium ion battery *** introduce the application of theoretical calculation method in solid-state batteries through the combination of theory and *** present the concept and assembly technology of solid-state batteries are *** basic parameters of solid-state electrolytes,especially sulfide-based solid-state electrolytes and their interface mechanisms with high-voltage cathode materials,are analyzed by theoretical *** present an overview on the scientific challenges,fundamental mechanisms,and design strategies for solid-state batteries,especially focusing on the issues of stability on solid-state electrolytes and the associated interfaces with both cathode and *** to the theoretical models,we can not only reveal the unprecedented mechanism from the atomic scale,but also analyze the interface problems in the battery thoroughly,thus effectively designing more promising electrolyte and interface coating *** blazed a new trial for engineering an interphase with improved interfacial compatibility for a long-term cyclability.

关键词： Theoretical simulation Sulfide-based electrolytes All solid-state battery Cathode-electrolyte interface Interface compatibility

Molding simulation of airfoil foam sandwich structure and interference optimization of foam-core

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Chinese Journal of Aeronautics 2024年第10期37卷 325-338页

作者： Qianying CEN Zeyang XING Qingyou wang {2. LI Zhigang wang Zhanjun WU Ling LIU school of Aerospace Engineering&Applied Mechanics Tongji UniversityShanghai 200092China AVIC Harbin Aircraft Industry Group Co.Ltd Harbin 150066China school of Aeronautics and Astronautics Dalian University of TechnologyDalian 116024China

During the Co-Cure Molding(CCM)of airfoil foam sandwich structure,it is challenging to avoid collapse of foam core at the trailing ***,an Equal Proportional Thickening(EPT)method is proposed to optimize the interference of polymethacrylimide(PMI)foam core during the CCM ***,based on some basic parameters of composite skin and foam core obtained by experiments or multi-scale simulations,a thermal-curing-mechanical coupling analysis for the CCM of foam sandwich structure is performed and the results show that the maximum stress within foam core occurs at the completion of mold-closing,which tends to decrease during the subsequent CCM ***,the foam core is thickened by traditional equidistant-thickening method,and the simulation reveals that the foam core at the trailing edge tends to collapse because of stress ***,if the foam core is thickened by the proposed EPT method,the mold-closing caused collapse at the trailing edge can be effectively avoided,and a thickening ratio range of 0.6%–2.0%is obtained,which is further proved by practical ***,the interference design scheme proposed can ensure the molding quality and effectively reduce the scrap of molded products.

关键词： Airfoil foam sandwich structure Polymethacrylimide(PMI)foam Interference Co-curing Molding simulation

Proppant transport in rough fracture networks using supercritical CO_(2.

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Petroleum Science 2024年第3期21卷 1852-1864页

作者： Yong zheng Meng-Meng Zhou Ergun Kuru Bin wang Jun Ni Bing {2. Ke Hu Hai Huang Hai-Zhu wang school of Petroleum Engineering Xi'an Shiyou UniversityXian710065ShaanxiChina Shaanxi Key Laboratory of Carbon Dioxide Sequestration and Enhanced Oil Recovery Xi'an710075ShaanxiChina State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China school of Mining and Petroleum Engineering University of AlbertaEdmontonTG2W2AlbertaCanad Shaanxi Yanchang Petroleum(Group)Co. Ltd.Xi'an710075ShaanxiChina

Proppant transport within fractures is one of the most critical tasks in oil,gas and geothermal reservoir stimulation,as it largely determines the ultimate performance of the operating *** transport in rough fracture networks is still a relatively new area of research and the associated transport mechanisms are still *** this study,representative parameters of rough fracture surfaces formed by supercritical CO_(2. fracturing were used to generate a rough fracture network model based on a spectral synthesis *** fluid dynamics(CFD)coupled with the discrete element method(DEM)was used to study proppant transport in this rough fracture *** reveal the turning transport mechanism of proppants into branching fractures at the intersections of rough fracture networks,a comparison was made with the behavior within smooth fracture networks,and the effect of key pumping parameters on the proppant placement in a secondary fracture was *** results show that the transport behavior of proppant in rough fracture networks is very different from that of the one in the smooth fracture *** turning transport mechanisms of proppant into secondary fractures in rough fracture networks are gravity-driven sliding,high velocity fluid suspension,and fracture structure *** the same injection conditions,supercritical CO_(2.with high flow Reynolds number still has a weaker ability to transport proppant into secondary fractures than *** of the supercritical CO_(2.needs to be increased beyond a certain value to have a significant effect on proppant carrying,and under the temperature and pressure conditions of this paper,it needs to be increased more than 2. times(about 0.94 m Pa s).Increasing the injection velocity and decreasing the proppant concentration facilitates the entry of proppant into the branching fractures,which in turn results in a larger stimulated reservoir *** results help to understand the pro

关键词： Reservoir stimulation CCUS Rough fracture network Supercritical CO_(2. Proppanttransport

MXene Sediment-Based Poly(vinyl alcohol)/Sodium Alginate Aerogel Evaporator with Vertically Aligned Channels for Highly Efficient Solar Steam Generation

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Nano-Micro Letters 2024年第10期16卷 638-654页

作者： Tian wang Meng Li Hongxing Xu Xiao wang Mingshu Jia Xianguang Hou Shuai Gao Qingman Liu Qihang {2. Mingwei Tian Lijun Qu Zhenhua Song Xiaohu Wu lili wang Xiansheng Zhang Shandong Key Laboratory of Medical and Health Textile Materials College of Textiles and ClothingState Key Laboratory of Bio-Fibers and Eco-TextilesResearch Center for Intelligent and Wearable TechnologyQingdao UniversityQingdao 266071People's Republic of China Department of Pharmacology Qingdao University School of PharmacyQingdao UniversityQingdao 266071People's Republic of China Shandong Institute of Advanced Technology Jinan 250100People's Republic of China College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266061People's Republic of China

Solar-driven interfacial evaporation from seawater is considered an effective way to alleviate the emerging freshwater crisis because of its green and environmentally friendly ***,developing an evaporator with high efficiency,stability,and salt resistance remains a key ***,with an internal photothermal conversion efficiency of 100%,has received tremendous research interest as a photothermal ***,the process to prepare the MXene with monolayer is inefficient and generates a large amount of“waste”MXene sediments(MS).Here,MXene sediments is selected as the photothermal material,and a three-dimensional MXene sediments/poly(vinyl alcohol)/sodium alginate aerogel evaporator with vertically aligned pores by directional freezing method is innovatively *** vertical porous structure enables the evaporator to improve water transport,light capture,and high evaporation *** swabs and polypropylene are used as the water channel and support,respectively,thus fabricating a self-floating *** evaporator exhibits an evaporation rate of 3.6 kg m^(-2.h^(-1)under one-sun illumination,and 18.37 kg m^(-2.of freshwater is collected in the condensation collection device after 7 h of outdoor sun *** evaporator also displays excellent oil and salt *** research fully utilizes“waste”MS,enabling a self-floating evaporation device for freshwater collection.

关键词： MXene sediments Porous structure Desalination Self-floating

Gradient-structure-enhanced dielectric energy storage performance of flexible nanocomposites containing controlled preparation of defective TiO_(2. and ferroelectric KNbO_(3) nanosheets

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Nano Research 2024年第5期17卷 4079-4088页

作者： Yan wang lili Zhao Ruicong Chen Wenhui Zhao Dengwei Hu Haoran wang Bin Cui Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Shaanxi Key Laboratory of Physico–Inorganic Chemistry Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China school of Information Science and Technology Northwest UniversityXi’an 710127China Engineering Research Center for Titanium Based Functional Materials and Devices in Universities of Shaanxi Province Faculty of Chemistry and Chemical EngineeringBaoji University of Arts and SciencesBaoji 721013China

Next generation power system needs dielectrics with increased dielectric energy ***,the low energy density of dielectrics limits their ***,an asymmetric trilayered nanocomposite,with a transition layer(TL),an insulation layer(IL),and a polarization layer(PL),is designed based on poly(vinylidene fluoride)-polymethyl methacrylate(PVDF-PMMA)matrix using KNbO_(3)(KN)and TiO_(2.(TO)as the *** morphology and defect control of the two-dimensional nano KN and nano TO fillers are realized via a hydrothermal method to increase the composite breakdown strength(E_(b))and the composite energy density(U_(e)).The asymmetric trilayered structure leads to a gradient electric field distribution,and the KN and TO nanosheets block charges transfer along z *** a result,the development path of the electrical trees is greatly curved,and E_(b) is effectively *** the Ue value of the nanocomposites reaches 17.79 J·cm^(-3) at 52. MV·m^(-1).On the basis,the composite Ue is further improved by defect control in TO *** nanocomposite KN/TO/PVDF-PMMA containing TO with less oxygen vacancy concentration(calcined at oxygen atmosphere)acquires a high Ue of 2..61 J·cm^(-3) at 548 MV·m^(-1).This study provides an idea for improving the energy storage performance by combining the design of the composite dielectric structure and the control of nanofillers’defect and morphology.

关键词： asymmetric trilayered structure two-dimensional energy density oxygen vacancies breakdown strength dielectric