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Improving EGT sensing data anomaly detection of aircraft auxiliary power unit

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Chinese Journal of Aeronautics 2020年第2期33卷 448-455页

作者： Liansheng LIU yu PENG Lulu WANG yu dong Datong LIU qing guo School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150080China China Southern Airlines Company Limited Shenyang Maintenance Base Shenyang 110169China China Southern Airlines Engineering Technology Research Center Shenyang 110169China

The reliability of the on-wing aircraft Auxiliary Power Unit(APU)decides the cost and the comfort of flight to a large *** most important function of APU is to help start main engines by providing compressed *** on the condition of sudden shutdown in the air,APU can offer additional thrust for ***,its condition monitoring has drawn much attention from the academic and industrial *** the on-wing sensing data which can reflect its condition,Exhaust Gas Temperature(EGT)is one of the most important *** ensure the reliability of EGT,one kind of data-driven anomaly detection framework for EGT sensing data is proposed based on the Gaussian Process Regression and Kernel Principal Component *** situations of one-dimensional and two-dimensional input data for EGT anomaly detection are considered,*** cross-validation experiments are carried out by utilizing the real condition data of APU,which are provided by China Southern Airlines Company Limited Shenyang Maintenance *** anomalous stuck condition of EGT sensing data is also *** results show that the proposed EGT sensing data anomaly detection method can achieve better performance of false positive ratio,false negative ratio and accuracy.

关键词： Anomaly detection Auxiliary power unit Condition-based maintenance Data-driven framework Exhaust gas temperature

Cranberry extract supplementation exerts preventive effects through alleviating Aβ toxicity in Caenorhabditis elegans model of Alzheimer's disease

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Chinese Journal of Natural Medicines 2016年第6期14卷 427-433页

作者： guo Hong dong yu-qing YE Bo-Ping School of Life Science and Technology China Pharmaceutical University Department of Biological Sciences Clemson University Institute for Engaged Aging Clemson University

Cranberry extract(CBE) rich in polyphenols are potent to delay paralysis induced by alleviating β-amyloid(Aβ) toxicity in C. elegans model of Alzheimer's disease(AD). In order to better apply CBE as an anti-AD agent efficiently, we sought to deterrmine whether preventive or therapeutic effect contributes more prominently toward CBE's anti-AD activity. As the level of Aβtoxicity and memory health are two major pathological parameters in AD, in the present study, we compared the effects of CBE on Aβtoxicity and memory health in the C. elegans AD model treated with preventive and therapeutic protocols. Our results revealed that CBE prominently showed the preventive efficacy, providing a basis for further investigation of these effects in mammals.

关键词： Aβ toxicity Cranberry polyphenols Prevention Body paralysis Caenorhabditis elegans

Experimental and Numerical Investigation on the Ultimate Strength of Stiffened Plates with Scanned Initial Geometrical Imperfection

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China Ocean Engineering 2019年第4期33卷 446-458页

作者： yu Yang-zhe feng guo-qing LI Chen-feng REN Hui-long College of Shipbuilding Engineering Harbin Engineering University

The study of the ultimate strength of stiffened plates is a hot topic in ocean engineering. The ultimate strength and behavior of collapse of stiffened plates were investigated using experimental and numerical methods. Two stiffened plates, with one and two half-bays in both longitudinal and transverse directions, were tested under the uniaxial compression. There were clamped boundaries at both ends of the stiffened panels and a restrained boundary on the transverse frames. The novel three-dimensional laser scanning technology was used to measure the initial geometric imperfections and the ultimate deformation of the stiffened panels after the test. The initial geometric deformation was imported into the finite element model, and the ultimate strength and behavior of collapse of the stiffened plates were calculated using the finite element analysis. FE analysis results based on the measured initial geometric imperfections were compared with the test results. It is concluded that structural deformation can be well measured by three-dimensional laser scanning technology, and can be conveniently imported into the finite element analysis. With the measured initial geometric imperfections considered, the FE analysis results agree well with the experimental results in ultimate strength, behavior of collapse, and the ultimate displacement distribution of the stiffened panels.

关键词： Stiffened plate ultimate strength experiment three dimensional laser scanning initial geometric imperfection

Heterostructured Co_(3)O_(4)-SnO_(2)composites containing oxygen vacancy with high activity and recyclability toward NH_(3)BH_(3)dehydrogenation

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Rare Metals 2023年第9期42卷 3013-3023页

作者： Hui-Ze Wang You-Xiang Shao yu-Fa feng yu-Jie Tan qing-yu Liao Xiao-dong Chen Xue-feng Zhang Zhao-Hui guo Hao Li School of Chemistry and Materials Engineering Huizhou UniversityHuizhou516007China Guangdong Provincial Key Laboratory for Electronic Functional Materials and Devices Huizhou UniversityHuizhou516007China

Ammonia borane(NH_(3)BH_(3),AB)has been regarded as a promising chemical hydrogen storage material owing to its high hydrogen density and superior ***,the development of low-cost and high-efficient heterogeneous catalysts for the dehydrogenation of AB has attracted considerable scholarly *** this study,heterostructured Co_(3)O_(4)-SnO_(2)catalysts containing oxygen vacancy(V_(o))with different Co/Sn atomic ratios(designated as V_(o)-Co-Sn_(5:x))were synthesized via a simple coprecipitation-calcination method under mild reaction *** catalyst containing an optimized Co/Sn atomic ratio of 5:2(V_(o)-Co-Sn_(5:2))exhibited robust catalytic performance with a turnover frequency value of 17.6mol_(H2)·mol^(-1)_(metal)·min^(-1).Moreover,82.6%of the original activity of the catalyst was retained after 14 catalytic cycles,indicating the high stability of the *** characterization combined with the density functional theory(DFT)calculation confirmed the transfer of electrons from Co_(3)O_(4)to Sn O_(2)and the distribution of the separated charges on SnO_(2)-Co_(3)O_(4)*** transfer of electrons and the distribution of charges facilitated the adsorption and activation of water on the catalyst,thus accelerating the dissociation of H_(2)O molecule(the ratedetermining step of AB hydrolysis).It was found that the V_(o)adjusted the electron structure of the catalysts rather than acted as active *** findings will provide researchers with useful information for designing cheap and highly efficient catalysts for catalytic AB hydrolysis.

关键词： Ammonia borane(AB) Cobalt-tin composite oxide Heterocatalysis Hydrogen production Oxygen vacancy

High-Temperature Structural Stabilities of Ni-Based SingleCrystal Superalloys Ni–Co–Cr–Mo–W–Al–Ti–Ta with Varying Co Contents

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Acta Metallurgica Sinica(English Letters) 2018年第2期31卷 127-133页

作者： yu Zhang qing Wang Hong-Gang dong Chuang dong Hong-yu Zhang Xiao-feng Sun Key Laboratory of Materials Modification by Laser Ion and Electron Beams (Dalian University of Technology) Ministry of Education Superalloys Division Institute of Metal Research Chinese Academy of Sciences

It has been recently pointed out that the compositions of industrial alloys are originated from cluster-plus-glueatom structure units in solid solutions. Specifically for Ni-based superalloys, after properly grouping the alloying elements into Al, Ni-like（Ni^-）, γ＇-forming Cr-like（Cr^-γ＇） and γ-forming Cr-like（Cr^-γ＇）, the optimal formula for single-crystal superalloys is established [Al–Ni^-12]（AlCr^-γ0：5Cr^-γ1：5）. The Co substitutions for Ni at the shell sites are conducted on the basis of the first-generation single-crystal superalloy AM3, formulated as [Al-Ni2-xCox]（Al1Ti0.25Ta0.25Cr1W0.25Mo0.25）, with x = 1.5, 1.75, 2 and 2.5（the corresponding weight percents of Co are 9.43, 11.0, 12.57 and 15.71, respectively）. The900 ℃ long-term aging follows the Lifshitz–Slyozov–Wagner theory（LSW theory）, and the Co content does not have noticeable influence on the coarsening rate of c0. The microstructure and creep behavior of the four（001） single-crystal alloys are investigated. The creep rupture lifetime is reduced as Co increases. The alloy with the lowest Co（9.43 Co） shows the longest lifetime of about 350 h at 1050 ℃/120 MPa, and all the samples show N-type rafting after creep tests.

关键词： Nickel-based single-crystal superalloys Cluster-plus-glue-atom model Composition formula Co

Microstructure and properties of a wear resistant Al-25Si-4Cu-1Mg coating prepared by supersonic plasma spraying

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International Journal of Minerals,Metallurgy and Materials 2020年第9期27卷 1287-1294页

作者： Tian-shun dong Ming Liu Yang feng guo-lu Li Xiao-bing Li School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China Key Laboratory for New Type of Function Material in Hebei Province Hebei University of TechnologyTianjin 300130China National Key Laboratory for Remanufacturing Academy of Armored Forces EngineeringBeijing 100072China

A high content silicon aluminum alloy(Al-25Si-4Cu-1Mg)coating was prepared on a 2A12 aluminum alloy by supersonic plasma *** morphology and microstructure of the coating were observed and *** hardness,elastic modulus,and bonding strength of the coating were *** wear resistance of the coating and 2A12 aluminum alloy was studied by friction and wear *** results indicated that the coating was compact and the porosity was only 1.5%.The phase of the coating was mainly composed ofα-Al andβ-Si as well as some hard particles(Al9Si,Al3.21Si0.47,and CuAl2).The average microhardness of the coating was HV 242,which was greater than that of 2A12 aluminum alloy(HV 110).The wear resistance of the coating was superior to 2A12 aluminum *** wear mechanism of the 2A12 aluminum alloy was primarily adhesive wear,while that of the coating was primarily abrasive ***,it is possible to prepare a high content silicon aluminum alloy coating with good wear resistance on an aluminum alloy by supersonic plasma spraying.

关键词： coating high silicon aluminum alloy microstructure mechanical properties wear resistance

Optimization of operation conditions for extracting lithium ions from calcium chloride-type oil field brine

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International Journal of Minerals,Metallurgy and Materials 2012年第4期19卷 290-294页

作者： Hong-jun Yang qing-hai Li bing Li feng-qin guo qing-fen Meng Wu Li qinghai Institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Fundamental Department Qinghai University Xining 81 O016 China

AI（OH）3 was prepared to extract lithium ions from calcium chloride-type oil field brine. The influences of four factors, namely temperature, Al3＋/Li＋ molar ratio, OH-/Al3＋ molar ratio, and contact time between AI（OH）3 and the brine, on the yield of lithium ions were investigated. It is found that their optimal values are 35℃, 4.5, 2.6, and 6 h, respectively. In the course of the experiment, the apparent pH value was observed. The results reveal that the apparent pH value has no remarkable influence on the yield of lithium ions. Meanwhile, the effects of the concentrations of calcium ions and magnesium ions in the brine on lithium recovery were studied. The results indicate that cal- cium ions have minor negative influence on the yield of lithium ions under optimal conditions, and magnesium ions slightly influence the yield of lithium ions.

关键词： lithium extraction oil field brine aluminium hydroxide

Left bundle branch area pacing combined with implantable cardioverter-defibrillator treatment for heart failure after myocardial infarction

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Journal of Geriatric Cardiology 2024年第5期21卷 577-582页

作者： bing-Chen guo Jian XU Yan-Zong LIU guo-qing DU Bo yu Shu-feng LI Wen-Juan DU Department of Cardiology the 2nd Affiliated Hospital of Harbin Medical UniversityHarbinChina The Key Laboratory of Myocardial Ischemia Chinese Ministry of EducationHarbinChina Department of Ultrasonography Guangdong Provincial People's HospitalGuangzhouGuangdongChina

Left bundle branch area pacing(LBBAP)has emerged as a new physiological pacing *** studies have confirmed the feasibility and efficacy of LBBAP for cardiac resynchronization therapy(CRT)in heart failure(HF)patients with left bundle branch block(LBBB)and a narrower QRS duration(QRSd)to have a higher percentage of super responders,and lower pacing thresholds than biventricular pacing(BiVP).

关键词： pacing branch bundle

Chain damage effects of multi-spaced plates by reactive jet impact

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Defence Technology（防务技术） 2021年第2期17卷 393-404页

作者： yuan-feng Zheng Cheng-hai Su Huan-guo guo qing-bo yu Hai-fu Wang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

Chain damage is a new phenomenon that occurs when a reactive jet impacts and penetrates multispaced *** reactive jet produces mechanical perforations on the spaced plates by its kinetic energy(KE),and then results in unusual chain rupturing effects and excessive structural damage on the spaced plates by its deflagration *** the present study,the chain damage behavior is initially demonstrated by *** reactive liners,composed of 26 wt%Al and 74 wt%PTFE,are fabricated through a pressing and sintering *** reactive liner thicknesses of 0.08 CD,0.10 CD and 0.12 CD(charge diameter)are chosen to carry out the chain damage *** results show a chain rupturing phenomenon caused by reactive *** constant reaction delay time and the different penetration velocities of reactive jets from liners with different thicknesses result in the variation of the deflagration position,which consequently determines the number of ruptured plates behind the ***,the finite-element code AUTODYN-3D has been used to simulate the kinetic energy only-induced rupturing effects on plates,based on the mechanism of behind armor debris(BAD).The significant discrepancies between simulations and experiments indicate that one enhanced damage mechanism,the behind armor blast(BAB),has acted on the ruptured ***,a theoretical model is used to consider the BAB-induced enhancement,and the analysis shows that the rupturing area on aluminum plates depends strongly upon the KE only-induced pre-perforations,the mass of reactive materials,and the thickness of plates.

关键词： Reactive materials Reactive jet Chain damage Behind armor blast