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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1147-1165页

作者： Zijian Peng Yuhao wang Shuqi wang Junteng Yao Qingyuan Zhao Enyu xie Guoliang Chen Zhigang wang Zhanguo Liu Yaming wang Jiahu Ouyang School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Materials and Metallurgical Engineering Inner Mongolia University of Science&TechnologyBaotou 014010China

The A_(2)B_(2)O_(7)-type rare earth zirconate compounds have been considered as promising candidates for thermal barrier coating(TBC) materials because of their low sintering rate,improved phase stability,and reduced thermal conductivity in contrast with the currently used yttria-partially stabilized zirconia (YSZ) in high operating temperature *** review summarizes the recent progress on rare earth zirconates for TBCs that insulate high-temperature gas from hot-section components in gas *** on the first principles,molecular dynamics,and new data-driven calculation approaches,doping and high-entropy strategies have now been adopted in advanced TBC materials *** this paper,the solid-state heat transfer mechanism of TBCs is explained from two aspects,including heat conduction over the full operating temperature range and thermal radiation at medium and high *** paper also provides new insights into design considerations of adaptive TBC materials,and the challenges and potential breakthroughs are further highlighted for extreme environmental *** for improving thermophysical performance are proposed in two approaches:defect engineering and material compositing.

关键词： rare earth zirconates thermal barrier coatings defect engineering doping and compositing thermal conductivity thermal expansion

Observer-based robust high-order fully actuated attitude autopilot design for spinning glide-guided projectiles

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Defence Technology（防务技术） 2024年第4期34卷 282-294页

作者： Wei wang Yuchen wang Shiwei Chen Yongcang Guo Zhongjiao Shi School of Aerospace Engineering Beijing Institute of TechnologyBeijing 10081China Northwest Industries Group CO. Ltd.Xi'an 710043China

This paper investigates the design of an attitude autopilot for a dual-channel controlled spinning glideguided projectile(SGGP),addressing model uncertainties and external *** on fixed-time stable theory,a disturbance observer with integral sliding mode and adaptive techniques is proposed to mitigate total disturbance effects,irrespective of initial *** introducing an error integral signal,the dynamics of the SGGP are transformed into two separate second-order fully actuated ***,employing the high-order fully actuated approach and a parametric approach,the nonlinear dynamics of the SGGP are recast into a constant linear closed-loop system,ensuring that the projectile's attitude asymptotically tracks the given goal with the desired *** the proposed composite control framework,the ultimately uniformly bounded stability of the closed-loop system is rigorously demonstrated via the Lyapunov *** of the effectiveness of the proposed attitude autopilot design is provided through extensive numerical simulations.

关键词： Spinning glide-guided projectile Attitude control Sliding mode disturbance observer Fixed-time stable theory High-order fully actuated approach

Insight into the adsorption behavior and mechanism of trace impurities from H_(2)O_(2) solution on functionalized zirconia by tuning the structure of amino groups

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 83-94页

作者： Yu Meng Yitong wang Guozhu Li Guozhu Liu Li wang Key Laboratory for Green Chemical Technology of Ministry Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Primary,secondary and tertiary amino-functionalized zirconia(ZrO_(2)-NH_(2),ZrO_(2)-NH and ZrO_(2)-N)was synthesized by the postgrafting method for the adsorption removal of typical metallic ions,phosphate and total oxidizable carbon from a real H_(2)O_(2) ***_(2)-NH_(2),ZrO_(2)-NH and ZrO_(2)-N exhibited similar pore sizes and sequentially increased zeta *** adsorption results of single and binary simulated solutions showed that the removal efficiency increased in the order of Fe^(3+)>Al^(3+)>Ca^(2+)>Na^(+).There is competitive adsorption between metallic ions,and Fe^(3+) has an advantage over the other metals,with a removal efficiency of 90.7%.The coexisting phosphate could promote the adsorption of metallic ions,while total oxidizable carbon had no effect on *** adsorption results of the real H_(2)O_(2)solution showed that ZrO_(2)-NH_(2) exhibited the best adsorption affinity for metallic ions,as did phosphate and total oxidizable carbon,with a total adsorption capacity of 120.9 mg·g_(-1).Density functional theory calculations revealed that the adsorption process of metallic ions involves electron transfer from N atoms to metals and the formation of N-metal bonds.

关键词： adsorption metallic ion phosphate total oxidizable carbon zirconia H_(2)O_(2)

A novel adaptive coordinated tracking control scheme for a morphing aircraft with telescopic wings

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Chinese Journal of Aeronautics 2024年第2期37卷 148-162页

作者： Enmei wang Hao LU Jianchun ZHANG Chenliang wang Jianzhong QIAO Hangzhou Innovation Institute Beihang UniversityHangzhou 310051China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Inspired by flight biology,morphing flight technology has great potential to improve the adaptability and maneuverability of *** paper is devoted to the flight control problem of morphing aircraft,and aimed at safe and fuel-saving flight through morphing ***,the longitudinal dynamics of a morphing aircraft with telescopic wings is modelled as a strict-feedback nonlinear *** fitting the expression of aerodynamic parameters by the mor-phing ratio,the model uncertainties induced by morphing errors are embedded in the *** meet the safety and fuel-saving requirements,an Adaptive Coordinated Tracking Control Scheme(ACTCS)is then proposed,which consists of a morphing control module and a tracking control *** the morphing control module,an on-line morphing decision model is given in an optimization process with respect to the morphing ratio,and a second-order tracking filter is introduced to smooth the decision output and ensure the physical *** the tracking control module,the novel adaptive controllers for the velocity and altitude subsystems are proposed based on the dynamic surface control method,in which adaptive mechanisms are designed to com-pensate for the model ***,the proposed ACTCS is simulated in nine different cases of the test flight mission,to verify its effectiveness,robustness and fuel-saving effect.

关键词： Morphing aircraft Adaptive tracking control Morphing decision Dynamic surface control Morphing error

Perception of fundamental science to boost lithium metal anodes toward practical application

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Green Energy & Environment 2024年第3期9卷 454-472页

作者： Jinkun wang Li wang Hong xu Li Sheng xiangming He Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China

As a key material for lithium metal batteries(LMBs),lithium metal is one of the most promising anode materials to break the bottleneck of battery energy density and a commonly used active material for reference *** lithium anodes are regarded as the holy grail of lithium batteries,decades of exploration have not led to the successful commercialization of LMBs,due mainly to the challenges related to the inherent properties of lithium *** pave the way for further investigation,herein,a comprehensive review focusing on the fundamental science of lithium are ***,the natures of lithium atoms and their isotopes,lithium clusters and lithium crystals are revisited,especially their structural and energetic ***,the electrochemical properties of lithium metal are *** important concepts and scientific questions,including the electronic structure of lithium,influence of high pressure and low temperature on the properties of lithium,factors influencing lithium deposition,generation of lithium dendrites,and electrode potential of lithium in different electrolytes,are explained and analyzed in *** to improve the performance of lithium anodes and thoughtfulness about the electrode potential in lithium battery research are proposed.

关键词： Lithium Cluster Crystal Physicochemical property Fundamental science

High corrosion and wear resistant electroless Ni–P gradient coatings on aviation aluminum alloy parts

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 155-164页

作者： Bo wang Jiawei Li Zhihui xie Gengjie wang Gang Yu College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410012China Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province/College of Chemistry and Chemical Engineering China West Normal UniversityNanchong 637002China Zhongchuan Machinery Ltd.Co. Aero Engine Corporation of ChinaChangsha 410200China

A Ni–P alloy gradient coating consisting of multiple electroless Ni–P layers with various phosphorus contents was prepared on the aviation aluminum alloy. Several characterization and electrochemical techniques were used to characterize the different Ni–P coatings’ morphologies, phase structures, elemental compositions, and corrosion protection. The gradient coating showed good adhesion and high corrosion and wear resistance, enabling the application of aluminum alloy in harsh environments. The results showed that the double zinc immersion was vital in obtaining excellent adhesion (81.2 N). The optimal coating was not peeled and shredded even after bending tests with angles higher than 90°and was not corroded visually after 500 h of neutral salt spray test at 35℃. The high corrosion resistance was attributed to the misaligning of these micro defects in the three different nickel alloy layers and the amorphous structure of the high P content in the outer layer. These findings guide the exploration of functional gradient coatings that meet the high application requirement of aluminum alloy parts in complicated and harsh aviation environments.

关键词： aluminum alloy electroless nickel coating corrosion adhesion

Semi-supervised remote sensing image scene classification with prototype-based consistency

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Chinese Journal of Aeronautics 2024年第2期37卷 459-470页

作者： Yang LI Zhang LI Zi wang Kun wang Qifeng YU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Deep learning significantly improves the accuracy of remote sensing image scene classification,benefiting from the large-scale ***,annotating the remote sensing images is time-consuming and even tough for *** neural networks trained using a few labeled samples usually generalize less to new unseen *** this paper,we propose a semi-supervised approach for remote sensing image scene classification based on the prototype-based consistency,by exploring massive unlabeled *** this end,we,first,propose a feature enhancement module to extract discriminative *** is achieved by focusing the model on the foreground ***,the prototype-based classifier is introduced to the framework,which is used to acquire consistent feature *** conduct a series of experiments on NWPU-rESISC45 and Aerial Image Dataset(AID).Our method improves the State-Of-The-Art(SOTA)method on NWPU-rESISC45 from 92.03%to 93.08%and on AID from 94.25%to 95.24%in terms of accuracy.

关键词： Semi-supervised learning remote sensing Scene classification Prototype network Deep learning

Comparison of tailpipe carbonyls and volatile organic compounds emissions from in-use gasoline/CNG bi-fuel vehicles

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Journal of Environmental Sciences 2024年第1期135卷 619-629页

作者： Jiachen Li Yunshan Ge xin wang Mengzhu Zhang Haohao wang School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

Ground-level ozone contamination has been globally an urban air quality issue,particularly for China,which has recently made significant progress in purifying its *** exhaust emissions from motor vehicles,predominantly carbonyls and volatile organic compounds(VOCs),are among the leading contributors to ozone *** this chassislevel study,the unregulated emissions from five China-5 certified gasoline/CNG bi-fuel taxis,along with their ozone forming potential(OFP),were *** is found that carbonyls and VOCs were mainly emitted during the starting phase no matter the engine was cold or *** to gasoline,CNG fueling reduced VOCs emissions on a large scale,especially in the starting phase,but had elevated *** a fleet average,CNG fueling derived 15%and 46%less OFP than gasoline in cold-and hot-start tests,*** contributed to over 90%of the total OFP of the *** terms of alleviating ground-level ozone contamination,CNG is a feasible alternative to gasoline on light-duty vehicles.

关键词： CNG Gasoline Carbonyls VOCs OFP

Study on theoretical model for electrical explosion resistivity of Al/Ni reactive multilayer foil

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Defence Technology（防务技术） 2024年第2期32卷 348-356页

作者： Zehao wang Tao wang Pengfei xue Mingyu Li Qingxuan Zeng State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China China Ship Development and Design Center Wuhan 430064China

Al/Ni reactive multilayer foil(rMF)possesses excellent comprehensive properties as a promising substitute for traditional Cu bridge.A theoretical resistivity model of Al/Ni rMF was developed to guide the optimization of ***/Ni rMF with different bilayer thicknesses and bridge dimensions were prepared by MEMS technology and electrical explosion tests were carried *** to physical and chemical reactions in bridge,the electrical explosion process was divided into 5 stages:heating of condensed bridge,vaporization and diffusion of Al layers,intermetallic combination reaction,intrinsic explosion,ionization of metal gases,which are obviously shown in measured voltage *** of interface and grain boundary scattering on the resistivity of film metal were *** on variations of substance and state,the resistivity was developed as a function of temperature at each *** explosion curves were calculated by this model at different bilayer thicknesses,bridge dimensions and capacitor voltages,which showed an excellent agreement with experimental ones.

关键词： Al/Ni reactive multilayer foil Electrical explosion resistivity model Phase transition Calculation

Optimal retrofitting scenarios of multi-objective energy-efficient historic building under different national goals integrating energy simulation,reduced order modelling and NSGA-II algorithm

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Building Simulation 2024年第6期17卷 933-954页

作者： Hailu Wei Yuanhao Jiao Zhe wang Wei wang Tong Zhang School of Architecture Southeast UniversityNanjingJiangsu Province210096China Key Laboratory of Urban and Architectural Heritage Conservation(Southeast University) Ministry of EducationNanjingChina Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina HKUST Shenzhen-Hong Kong Collaborative Innovation research Institute FutianShenzhenChina

retrofitting a historic building under different national goals involves multiple objectives,constraints,and numerous potential measures and packages,therefore it is time-consuming and challenging during the early design *** study introduces a systematic retrofitting approach that incorporates standard measures for the building envelope(walls,windows,roof),as well as the heating,cooling,and lighting *** retrofit objectives are delineated based on prevailing Chinese *** retrofit measures function as genes to optimize energy-savings,carbon emissions,and net present value(NPV)by employing a log-additive decomposition approach through energy simulation techniques and NSGA-II,yielding 185,163,and 8 ***,a weighted sum method is proposed to derive optimal solutions across multiple *** framework is applied to a courtyard building in Nanjing,China,and the outcomes of the implementation are scrutinized to ascertain the optimal retrofit package under various *** this retrofit,energy consumption can be diminished by up to 63.62%,resulting in an NPV growth of 151.84%,and maximum rate of 60.48%carbon *** three result values not only indicate that the optimal values are achieved in these three aspects of energy saving,carbon reduction and economy,but also show the possibility of possible equilibrium in this multi-objective optimization *** framework proposed in this study effectively addresses the multi-objective optimization challenge in building renovation by employing a reliable optimization algorithm with a computationally efficient reduced-order *** provides valuable insights and recommendations for optimizing energy retrofit strategies and meeting various performance objectives.

关键词： historic building energy-efficient retrofitting building energy simulation log-additive decomposition approach NSGA-II