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Overview of control-centric integrated design for hypersonic vehicles

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Astrodynamics 2018年第4期2卷 307-324页

作者： Yanbin Liu Boyi Chen Yuhui Li Haidong Shen College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing210016China

Hypersonic vehicles(HSVs)exhibit significant advantages over other vehicles,including the wide range of velocity and large airspace types,and these features have contributed to the rapid development of HSVs in the last 20 ***,hypersonic technologies have become a multidisciplinary research topic in the fields of aerodynamics,propulsion,structure,material,and *** types of re-entry gliding,air-breathing cruise,and aerospace vehicles have been designed to realize ambitious tasks,which in turn influenced the technological advancements and process change in the *** paper summarizes the control-oriented integrated design of ***,the status of current research on the distinct characteristics and technique issues of HSVs is ***,the progresses made on complex modeling,guidance and control,and trajectory optimization are elaborated to exhibit the significant research interest in hypersonic *** control-integrated design of HSVs is emphasized to solve the multidisciplinary design problems associated with the model and its control and *** strategies regarding the multidisciplinary optimization design are also proposed to solve the integrated design ***,suggestions are provided for the control-oriented integrated design of HSVs.

关键词： hypersonic vehicles integrated design flight control

Blind restoration of turbulence degraded images based on two-channel alternating minimization algorithm

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Optoelectronics Letters 2022年第2期18卷 122-128页

作者： YANG Huizhen LI Songheng LI Xin ZHANG Zhiguang YANG Haibo LIU Jinlong jiangsu Ocean University Lianyungang 222005China jiangsu Marine Resources Development Research Institute Lianyungang 222005China Key Laboratory of Electro-Optical Information Control and Security Technology The 53th Research Institute of China Electronic Technology Group CorporationTianjin 300308China

Due to the atmospheric turbulence and the system noise, images are blurred in the astronomical or space object detection. Wavefront aberrations and system noise make the capability of detecting objects decrease greatly. A two-channel image restoration method based on alternating minimization is proposed to restore the turbulence degraded images. The images at different times are regarded as separate channels, then the object and the point spread function(PSF) are reconstructed in an alternative way. There are two optimization parameters in the algorithm: the object and the PSF. Each optimization step is transformed into a constraint problem by variable splitting and processed by the augmented Lagrangian method. The results of simulation and actual experiment verify that the two-channel image restoration method can always converge rapidly within five iterations, and values of normalized root mean square error(NRMSE) remain below 3% after five iterations. Standard deviation data show that optimized alternating minimization(OAM) has strong stability and adaptability to different turbulent levels and noise levels. Restored images are approximate to the ideal imaging by visual assessment, even though atmospheric turbulence and systemnoise have a strong impact on imaging. Additionally, the method can remove noise effectively during the process of image restoration.

关键词： turbulence minimization algorithm

Laser Cladding Fe-Al-Cr Coating with Enhanced Mechanical Properties

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Journal of Wuhan University of Technology(Materials Science) 2019年第5期34卷 1197-1204页

作者： LUO Xixi YAO Zhengjun School of Materials Engineering Xi'an Aeronautical UniversityXi'an 710077China College of Material Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Business and Trade Nanjing Institute of Industry TechnologyNanjing 210046China

Dense Fe-Al-Cr coatings with approximately 50 μm in thickness are successfully prepared on the 1045 carbon steel substrates via a laser cladding process. Proper Cr content(5 at% Cr) will lead to decrease in the melting point, and improves the viscosity of the liquid and the nucleation rate of the molten pool, leading to refining grains of the solidification structure. As a result, the Fe-29 Al-5 Cr laser cladding layer exhibits the best hardness, plasticity properties, and wear resistance at 400 °C. Excessive Cr for the Fe-29 Al-7.5 Cr coating leads to the formation of Cr2 Al in the grain boundaries and thermal vacancies during the solidification process, resulting in inferior mechanical properties and poor tribological behavior.

关键词： Fe-Al-Cr intermetallic alloys and compounds laser processing mechanical properties nanoindentation

Multi-objective layout optimization of a satellite module using the Wang-Landau sampling method with local search

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Frontiers of Information Technology & Electronic Engineering 2016年第6期17卷 527-542页

作者： Jing-fa LIU Liang HAO Gang LI Yu XUE Zhao-xia LIU Juan HUANG jiangsu Engineering Center of Network Monitoring Nanjing University of Information Science&TechnologyNanjing 210044China School of Computer&Software Nanjing University of Information Science&TechnologyNanjing 210044China School of Mathematics and Statistics Nanjing University of Information Science&TechnologyNanjing 210044China Office of lnformationization Construction and Management Nanjing University of Information Science&TechnologyNanjing 210044China

The layout design of satellite modules is considered to be NP-hard. It is not only a complex coupled system design problem but also a special multi-objective optimization problem. The greatest challenge in solving this problem is that the function to be optimized is characterized by a multitude of local minima separated by high-energy barriers. The Wang-Landau(WL) sampling method, which is an improved Monte Carlo method, has been successfully applied to solve many optimization problems. In this paper we use the WL sampling method to optimize the layout of a satellite module. To accelerate the search for a global optimal layout, local search(LS) based on the gradient method is executed once the Monte-Carlo sweep produces a new layout. By combining the WL sampling algorithm, the LS method, and heuristic layout update strategies, a hybrid method called WL-LS is proposed to obtain a final layout scheme. Furthermore, to improve significantly the efficiency of the algorithm, we propose an accurate and fast computational method for the overlapping depth between two objects(such as two rectangular objects, two circular objects, or a rectangular object and a circular object) embedding each other. The rectangular objects are placed orthogonally. We test two instances using first 51 and then 53 objects. For both instances, the proposed WL-LS algorithm outperforms methods in the literature. Numerical results show that the WL-LS algorithm is an effective method for layout optimization of satellite modules.

关键词： Packing Layout design Satellite module Wang-Landau algorithm

Amorphous FeCoNi-S as efficient bifunctional electrocatalysts for overall water splitting reaction

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Chinese Chemical Letters 2023年第2期34卷 576-581页

作者： Runze He Chunyan Wang Ligang Feng School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

Developing bifunctional electrocatalysts for overall water splitting reaction is still highly desired but with large challenges. Herein, an amorphous Fe Co Ni-S electrocatalyst was developed using thioacetamide for the sulfuration of Fe Co Ni hydroxide during the hydrothermal process. The obtained catalyst exhibited an amorphous structure with hybrid bonds of metal-S bond and metal-O bonds in the catalyst system. The optimized catalyst showed a largely improved bifunctional catalytic ability to drive water splitting reaction in the alkaline electrolyte compared to the Fe Co Ni hydroxide. It required an overpotential of 280 m V and 80 m V(No-IR correction) to offer 10 m A/cm^(2)for water oxidation and reduction respectively;a low cell voltage of 1.55 V was required to reach 10 m A/cm^(2)for the water electrolysis with good stability for12 h. Moreover, this catalyst system showed high catalytic stability, catalytic kinetics, and Faraday efficiency for water splitting reactions. Considering the very low intrinsic activity of Fe Co Ni hydroxide, the efficient bifunctional catalytic ability should result from the newly formed hybrid active sites of metallic metal-S species and the high valence state of metal oxide species. This work is effective in the bifunctional catalytic ability boosting for the transition metal materials by facile sulfuration in the hydrothermal approach.

关键词： Bifunctional electrocatalyst Amorphous Overall water splitting FeCoNi hydroxide Sulfuration

Energy saving and environment-friendly element-transfer reactions with industrial application potential

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Chinese Chemical Letters 2020年第5期31卷 1078-1082页

作者： Chao Chen Yitao Cao Xixi Wu Yuanli Cai Jian Liu Lin Xu Kehong Ding Lei Yu School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Tianzhu Hongfu Lithium Industry Technology Development Company Limited Wuwei 733200China Department of Applied Chemistry Faculty of EngineeringKyushu Institute of TechnologyKitakyushu 804-8550Japan jiangsu Yangnong Chemical Group Company Limited Yangzhou 225009China

Herein we wish to propose the concept of"element-transfer reaction",which may afford the access to elemental compounds by transferring certain elements from easily available resources efficiently,concisely and precisely.A good element-transfer reaction with industrial application potential shall not generate waste and is performed under energy-saving and environment-friendly *** the past decade,we have developed a series of methods for the synthesis of fluorine-and seleniumcontaining compounds via the fluorine-and selenium-transfer reactions,while the redox reactions we re considered to be the oxygen-and hydrogen-transfer reactions as well and were also widely studied by our group for producing the high-value-added fine *** of these technologies have been successfully *** review summarizes our staged research results on fluorine-,oxygen-,hydrogen-and selenium-transfer reactions and makes a prospect on the developing trend in the field.

关键词： Element-transfer reaction Fluorine Redox Selenium Green chemistry Photocatalysis

Highly efficient Zr doped-TiO_2/glass fiber photocatalyst and its performance in formaldehyde removal under visible light

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Journal of Environmental Sciences 2017年第10期29卷 61-69页

作者： Chao Huang Yaping Ding Yingwen Chen Peiwen Li Shemin Zhu Shubao Shen State Key Laboratory Materials of Materials-Oriented Chemical Engineering Nanjing Tech University jiangsu Engineering Technology Research Center of Environmental Cleaning Material School of Environmental Science and EngineeringNanjing University of Information Science and Technology Department of Aerospace and Mechanical Engineering the University of Arizona College of Material Science and Engineering Nanjing Tech University

Zr-doped-TiO2 loaded glass fiber（ZT/GF） composite photocatalysts with different Zr/Ti ratios were prepared with a sol–gel process. Zr4＋can replace Ti4＋in the TiO2 lattice, which is conducive to forming the anatase phase and reducing the calcination temperature. The glass fiber carrier was responsible for better dispersion and loading of Zr-doped-TiO2 particles, improving the applicability of the Zr-doped-TiO2. The ZT/GF photocatalysts were characterized by X-ray diffraction（XRD）, scanning electron microscope（SEM）, Fourier transform infrared spectroscopy（FT-IR）, ultraviolet–visible spectroscopy（UV–vis） and Barrett–Joyner–Halenda（BJH）. The performance of photocatalysts with different loading was evaluated in formaldehyde degradation under visible light at room temperature. ZT/GF0.2exhibited the highest activity, with a formaldehyde removal rate as high as 95.14% being observed, which is better than that of the photocatalyst particles alone. The stability of the catalyst was also tested, and ZT/GF exhibited excellent catalytic performance with 94.38%removal efficiency, even after seven uses.

关键词： TiO2 Zr Photocatalyst Formaldehyde Glass fiber

Near-Iinear elastic deformation behavior of a novel Zr-Ti-Nb-Sn alloy with multi-phase microstructures ofβ,α"andα'phases

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Rare Metals 2023年第5期42卷 1670-1677页

作者： Wen Ma Hao Huang Wang Ding Shun Guo Hai-Xia Liu Xiao-Nong Cheng School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013China China Grinm Group Co. Ltd.Bejing100088China

In this work,a multi-phase Zr-30Ti-7Nb-4Sn alloy with large near-linear elastic deformability was prepared by the solution treatment plus pre-straining(S TP)treatment,and the underlying mechanism accountable for the near-linear elastic deformation was systematically *** was found that the Zr-30Ti-7Nb-4Sn alloy was composed ofβ,α″andα′phases,and numerous dislocations were formed in the alloy specimen after STP *** the retarding effect of high-density dislocations,the stress-induced martensitic(SIM)transformation fromβtoα″phases took place homogeneously and continuously during loading,in conjunction with the occurrence of elastic deformation ofβ,α″andα′*** the entire tensile procedure,no observable phase transformation occurred betweenα′martensite andβ***,the near-linear elastic deformation capability in STP Zr-30Ti-7Nb-4Sn alloy is mainly ascribed to the coupling actions of consecutiveβ→α″SIM transformation and intrinsic elastic deformation ofβ,α″andα′*** experimental results provide a basis for designing and developing novel multi-phase Zr-based alloys that possess large near-linear deformability.

关键词： Zr-based alloy Multi-phase Near-linear deformation behavior Martensitic transformation

Polyaniline-supported tungsten-catalyzed oxidative deoximation reaction with high catalyst turnover number

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Chinese Chemical Letters 2023年第1期34卷 347-350页

作者： Wen Li Feng Wang Yaocheng Shi Lei Yu School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

Polyaniline-supported tungsten(W@PANI)was easily prepared by immersing polyaniline(PANI)in the aqueous solution of *** was found to be an efficient catalyst for oxidative deoximation reaction,the very important transformation for pharmaceutical *** the green features,the method employed very few of catalytic tungsten(0.048 mol%*** substrates),resulting in the high turnover numbers(TONs)of the catalyst(ca.103 mol/mol)and the low metal residues in product(<0.1 ppm).The reaction is applicable for a variety of substrates,including those containing heterocycles,which are key intermediates in medicine *** has also been successfully magnified to kilogram scale production to afford the desired carbonyl products smoothly.

关键词： Deoximation Carbonyl Tungsten Free radical reaction Oxidation