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Chinese j.urnal of Aeronautics 2024年第6期37卷 410-424页

作者： Qiannan TAO Yanrong WANG Dasheng wei Shun YANG School of Energy and Power Engineering Beihang UniversityBeijing 100191China j.angx. Research Institute of Beihang University Nanchang 330096China

Predicting the thickness of Thermally Grown Ox.de(TGO)and the residual stresses induced by TGO growth in the Thermal Barrier Coatings(TBCs)is significant work in analyzing the failure of *** practical applications,the operating temperature,ox.gen partial pressure,aluminium content in TBCs,and porosity of the topcoat affect the ox.dation ***,a novel ox.dation rate model is proposed to describe the effect of such *** parameters in the proposed model were fitted with isothermal degradation test data from prior ***,a method for calculating the residual stress in a disk-shaped specimen was developed based on the ox.dized growth strain model and the ox.dized ***,a variable-temperature ox.dation ex.eriment was performed to validate the new ox.dation *** average error between the predicted and ex.erimental thicknesses is approx.mately 10%,and the average error between the residual stresses is 30%.Under the variable-temperature condition,the error between the predicted thickness and the average ex.erimental thickness is 3.9%.

关键词： Thermal barrier coatings Ox.dation Gas turbine Residual stresses Sintering

Optimizing circumferential assembly angle of rotor parts connected by curvic couplings based on acquired tooth surface error data

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Chinese j.urnal of Aeronautics 2024年第3期37卷 404-416页

作者： Huibin SUN Meng LIU Yingzhi ZHANG Chenle wei Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China AECC South Industry Company Limited Zhuzhou 412002China

Due to the ex.ellent self-centering and load-carrying capability,curvic couplings have been widely used in advanced aero-engine ***,curvic tooth surface errors lead to poor assembly *** physical-master-gauge-based indirect tooth surface error measurement and circumferential assembly angle optimization methods have the disadvantages of high cost and weak *** unknown tooth surface fitting mechanism is a big barrier to assembly precision prediction and ***,this work puts forward a data-driven assembly simulation and optimization approach for aero-engine rotors connected by curvic *** origin of curvic tooth surface error is deeply *** 5-ax.s sweep scan method,a large amount of high-precision curvic tooth surface data are acquired *** on geometric models of parts,the fitting mechanism of curvic couplings is uncovered for assembly precision simulation and prediction.A circumferential assembly angle optimization model is developed to decrease ax.al and radial assembly *** results show that the assembly precision can be predicted accurately and improved *** uncovering the essential principle of the assembly precision formation and proposing circumferential assembly angle optimization model,this work is meaningful for assembly quality,efficiency and economy improvement of multistage aero-engine rotors connected by curvic couplings.

关键词： Curvic couplings Tooth surface error Assembly precision Ax.al and radial runouts Circumferential assembly angle

A discussion of fatigue properties of notched specimens subj.cted to prestressing treatment machined from FGH4097

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Chinese j.urnal of Aeronautics 2024年第4期37卷 508-523页

作者： Rongx. SHI Dasheng wei Le HAN Shun YANG School of Energy and Power Engineering Beihang UniversityBeijing 100191China j.angx. Research Institute Beihang UniversityNanchang 330096China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

Ex.erimental and numerical investigations were performed to reveal the effect of prestress on the fatigue properties of FGH4097 so as to quantitatively evaluate the overspeed benefit of the disc of aeroengine. A corresponding ex.eriment was performed to ex.mine the effect of prestress on the fatigue life of FGH97. A complete model describing the fatigue properties of the prestressed notch specimen was proposed. After the modification of mean stress, stress gradient and prestressing treatment, the model is finally verified by fatigue test of presstressed notch specimens machined from FGH4097 with satisfactory accuracy and good engineering applicability. The new model highlights that for the variable fatigue loads, the introduction of appropriate prestress is ex.ected to benefit to the notch specimens and certainly to the disc of aeroengine regards of their fatigue properties. Both the calculation method of fatigue life parameters and the prestress correction model are proved to have good prediction accuracy.

关键词： Turbine blisk Overspeed test Prestress Fatigue life prediction FGH4097

Long-term Integration Ability of the Submillimeter Wave Astronomy Satellite(SWAS)Spectral Line Receivers

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Research in Astronomy and Astrophysics 2024年第6期24卷 315-322页

作者： Bing-Ru Wang Di Li Paul F.Goldsmith j.ngwen Wu Chao-wei Tsai Rudolf Schieder Gary j.Melnick National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Research Center for Astronomical Computing Zhejiang LaboratoryHangzhou 311100China j.t Propulsion Laboratory California Institute of TechnologyPasadenaCA 91109USA Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China KOSMA I.Physik.InstitutUniversität zu KölnZülpicher Str.7750937 KölnGermany Center for Astrophysics|Harvard&Smithsonian 60 Garden StreetMS 66CambridgeMA 02138USA

The Submillimeter Wave Astronomy Satellite(SWAS)was the first space telescope capable of high spectral resolution observations of terahertz spectral *** have investigated the integration ability of its two receivers and spectrometer during five and a half years of on-orbit *** CI,O_(2),H_(2)O,and^(13)CO spectra taken toward all observed Galactic sources were *** present results are based on spectra with a total integration time of up to 2.72×10~4hr(■10~8s).The noise in the spectra is generally consistent with that ex.ected from the radiometer equation,without any sign of approaching a noise *** noise performance reflects the ex.remely stable performance of the passively cooled front end as well as other relevant components in the SWAS instrument throughout its mission lifetime.

关键词： telescopes space vehicles:instruments instrumentation:miscellaneous ISM:lines and bands

Effects of Aging at 550℃ on α'-Martensitic Transformation of High Si-Bearing Metastable Austenitic Stainless Steel Weld Metal

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1467-1479页

作者： Yakui Chen Shitong wei Dong Wu Shanping Lu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The high Si-bearing 15Cr-9Ni-Nb metastable austenitic stainless steel weld metal was prepared via gas tungsten arc welding and then processed by stabilized heat treatment(SHT)at 850℃ for 3 *** effects of 550℃ aging on the α'-martensitic transformation of the as-welded and the SHT weld metals were *** results showed that the weld metal had poor thermal stability of *** precipitation of NbC during the 850℃ SHT made the thermal stability of the local matrix.decrease and led to the formation of a large amount of C-depleted α'-*** precipitation of coarse σ-phase at the δ-ferrite led to the Cr-depleted zone and the formation of Cr-depleted α'-martensite at the early stage of 550℃ *** homogenized diffusion of C and Cr in the matrix.during 550℃ aging led to the restoration of austenitic thermal stability and the decrease of α'-martensite *** C-depleted α'-martensite content in the SHT weld metal decreased rapidly at the early stage of aging due to the fast diffusion rate of the C atom in the matrix.while the Cr-depleted α'-martensite decreased at the later stage of aging due to the decreased diffusion rate of the Cr.

关键词： Metastable austenitic stainless steel weld metal α'-martensitic transformation δ-ferrite σ-phase

Zinc Ox.de Nanostructured Biosensor for Glucose Detection

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j.urnal of Materials Science & Technology 2008年第4期24卷 649-656页

作者： x. W.Sun j.x. Wang A. wei School of Electrical and Electronic Engineering Nanyang Technological University Nanyang Avenue Singapore 639798 Singapore

Zinc ox.de （ZnO） nanocombs were fabricated by vapor phase transport, and nanorods and hierarchical nanodisk structures by aqueous thermal decomposition. Glucose biosensors were constructed using these ZnO nanostructures as supporting materials for glucose ox.dase （GOx. loading. These ZnO glucose biosensors showed a high sensitivity for glucose detection and high affinity of GOx.to glucose as well as the low detection limit. The results demonstrate that ZnO nanostructures have potential applications in biosensors.

关键词： ZnO nanostructures Crystal structure Glucose Biosensor

Construction of metallo-complex.s with 2,2′:6′,2″-terpyridine substituted triphenylamine in different modified positions and their photophysical properties

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Chinese Chemical Letters 2024年第7期35卷 301-305页

作者： Shengwen Guan Zhaotong wei Ningx. Han Yude wei Bin x. Ming Wang j.nj.an Shi State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

The stable coordinated metallo-complex.s based on 2,2′:6′,2″-terpyridine(tpy)and its derivatives have been widely researched for various wide-ranging applications in photoelectronics,catalysis,sensor,photoluminescence,and so ***,the most reported studies ignored the comprehensive comparison between structures modified by different positions and ***,we design a series of metallo-complex.s which were assembled with tpy substituted triphenylamine(TPA)at different positions and metal ions and ex.lored their photophysical *** the solution state,MLE_(2)based on the 5,5″-positions modification showed the highest PLQYs and PL *** the increase of solvent polarity,MLB2ex.ibit the largest *** the solid state,from MLA_(2)to MLE_(2),the emission colours are gradually red-shifted from yellow to *** findings in this work may pave a new way to design functional metallo-complex.s,not j.st for PL properties.

关键词： Metallo-complex.s 2,2′:6′,2″-terpyridine Triphenylamine Different modified positions Photophysical properties

Electroacupuncture activates AMPKa1 to improve learning and memory in the APP/PS1 mouse model of early Alzheimer's disease by regulating hippocampal mitochondrial dynamics

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j.urnal of Integrative Medicine 2024年第5期22卷 588-599页

作者： wei-wei j.a Hua-wei Lin Min-guang Yang Ya-ling Dai Yan-yi Ding Wen-shan x. Si-nuo Wang Ya-j.n Cao Sheng-x.ang Liang Zhi-fu Wang Cong Chen wei-lin Liu College of Rehabilitation Medicine Fujian University of Traditional Chinese Medicine The Institute of Rehabilitation Industry Fujian University of Traditional Chinese Medicine National-Local j.int Engineering Research Center of Rehabilitation Medicine Technology Fujian University of Traditional Chinese Medicine Traditional Chinese Medicine Rehabilitation Research Center of State Administration of Traditional Chinese Medicine Fujian University of Traditional Chinese Medicine

Obj.ctive: Studies have shown that electroacupuncture(EA) can alleviate cognitive impairments from Alzheimer's disease(AD) by regulating the ex.ression of adenosine monophosphate-activated protein kinase(AMPK), but the specific mechanism involved remains to be elucidated. Therefore, this study ex.lores the potential mechanism by which EA improves cognitive function from the perspective of mitochondrial ***: The four-month-old transgenic mice with amyloid precursor protein(APP)/presenilin 1(PS1)and AMPKa1-subunit conditional knockout(AMPKa1-cKO) were used for ex.eriments. To evaluate the effects of EA treatment on cognitive function, the T-maze and Morris water maze were used. In addition,chemical ex.hange saturation transfer, thioflavin staining, transmission electron microscopy, mitochondrial membrane potential, and Western blotting were used to ex.mine the potential mechanisms underlying the effects of EA on APP/PS1 ***: Both APP/PS1 mice and AMPKa1-cKO mice ex.ibited dysfunction in mitochondrial dynamics accompanied by learning and memory impairment. Inactivation of the AMPK/perox.some proliferatoractivated receptor-γ coactivator-1a(PGC-1a) pathway increased pathological amyloid-β(Aβ) deposition and aggravated the dysfunction in mitochondrial dynamics. In addition, EA rescued learning and memory deficits in APP/PS1 mice by activating the AMPK/PGC-1a pathway, specifically by reducing pathological Aβ deposition, normalizing energy metabolism, protecting the structure and function of mitochondria,increasing the levels of mitochondrial fusion proteins, and downregulating the ex.ression of fission proteins. However, the therapeutic effect of EA on cognition in APP/PS1 mice was hindered by ***: The regulation of hippocampal mitochondrial dynamics and reduction in Aβ deposition via the AMPK/PGC-1a pathway are critical for the ability of EA to ameliorate cognitive impairment in APP/PS1 mice.

关键词： Adenosine monophosphate-activated protein kinase Alzheimer’s disease Cognitive impairment Electroacupuncture Hippocampus Mitochondrial dynamics

Classification of complete 3-dimensional self-shrinkers in the Euclidean space R^(4)

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Science China Mathematics 2024年第4期67卷 873-882页

作者： Qing-Ming Cheng Zhi Li Guox.n wei Department of Applied Mathematics Faculty of ScienceFukuoka UniversityFukuoka 814-0180Japan College of Mathematics and Information Science Henan Normal UniversityXinxiang 453007China School of Mathematical Sciences South China Normal UniversityGuangzhou 510631China

In this paper,we completely classify 3-dimensional complete self-shrinkers with the constant norm S of the second fundamental form and the constant f3in the Euclidean space R^(4),where hij.s are components of the sec... 详细信息

关键词： mean curvature ow self-shrinker the generalized max.mum principle

Reduced-order modeling and vibration transfer analysis of a fluid-delivering branch pipeline that consider fluid–solid interactions

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Frontiers of Mechanical Engineering 2024年第2期19卷 75-97页

作者： Wenhao j. Hongwei MA wei SUN Yinhang CAO School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems(Ministry of Education) Northeastern UniversityShenyang 110819China College of Power and Energy Engineering Harbin Engineering UniversityHarbin 150001China

The efficient dynamic modeling and vibration transfer analysis of a fluid-delivering branch pipeline(FDBP)are essential for analyzing vibration coupling effects and implementing vibration reduction ***,this study proposes a reduced-order dynamic modeling method suitable for FDBPs and then analyzes the vibration transfer *** the modeling method,the finite element method and absorbing transfer matrix.method(ATMM)are integrated,considering the fluid–structure coupling effect and fluid *** dual-domain dynamic substructure method is developed to perform the reduced-order modeling of FDBP,and ATMM is adopted to reduce the matrix.order when solving fluid ***,the modeling method is validated by ex.eriments on an H-shaped branch ***,transient and steady-state vibration transfer analyses of FDBP are performed,and the effects of branch locations on natural characteristics and vibration transfer behavior are *** show that transient vibration transfer represents the transfer and conversion of the kinematic,strain,and damping energies,while steady-state vibration transfer characteristics are related to the vibration *** addition,multiple-order mode ex.hanges are triggered when branch locations vary in frequency-shift regions,and the mode-ex.hange regions are also the transformation ones for vibration transfer patterns.

关键词： fluid-delivering branch pipeline vibration transfer analysis reduced-order modeling fluid-solid interactions finite element method absorbing transfer matrix.method