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Chinese Journal 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 excellent 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-axis 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 axial 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 Axial and radial runouts Circumferential assembly angle

A Local Tb Theorem for Square Functions and Parabolic Layer Potentials

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1941-1966页

作者： zhi Dan WANG Guo Ming zhang School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816P.R.China Frontiers Science Center for Nonlinear Expectations Ministry of EductionResearch Center for Mathematics and Interdisciplinary SciencesShandong UniversityQingdao266237P.R.China

In this paper,we give a locally parabolic version of Tb theorem for a class of vector-valued operators with off-diagonal decay in L^(2) and certain quasi-orthogonality on a subspace of L^(2),in which the testing functions themselves are also *** an application,we establish the boundedness of layer potentials related to parabolic operators in divergence form,defined in the upper half-space Rn+2+:={(x,t,λ)∈R^(n+1)×(0,∞)},with uniformly complex elliptic,L^(∞),t,λ-independent coefficients,and satisfying the De Giorgi/Nash estimates.

关键词： Local Tb theorems Calderon-Littlewood-Paley family Parabolic layer potentials Carleson measure estimates

Restricted Arc-Connectivity of Harary Digraphs

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Journal of the Operations Research Society of China 2024年第2期12卷 540-547页

作者： Jun-Hao zhang Ji-Xiang meng College of Mathematics and System Science Xinjiang UniversityUrumqi 830046XinJiangChina

The h-restricted arc-connectivity of a digraph is an important parameter to measure fault-tolerance of interconnection *** paper determines that the h-restricted arc-connectivity of the Harary digraph D=G(n;1,2,.:,k)i... 详细信息

关键词： Restricted arc-connectivity λ_(h)(D) Super-λ_(h) λ_(h)-Atom λ_(h)-Superatom

Endogenous Candida albicans endophthalmitis in a patient with chronic renal failure on hemodialysis

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 979-981页

作者： meng-Ya Liu zhi-Fan Chen Hao-Sheng Liu Qian-Li meng Department of Ophthalmology Guangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhou 510080Guangdong ProvinceChina The Fourth Affiliated Hospital of Guangzhou Medical University Guangzhou 511400Guangdong ProvinceChina

Dear Editor,We report a rare case of endogenous endophthalmitis caused by Candida albicans in a patient with chronic renal failure concomitant hemodialysis.A 71-year-old man with a history of hypertension and 2-year chronic renal failure on hemodialysis via a native arteriovenous fistula(AVF)was presented to the local hospital due to fever 3wk *** pathogens were detected through blood culture on admission,and his fever gradually subsided with intravenous ceftriaxone *** a week of fever,he experienced progressive blurred vision in both eyes,accompanied by pain and *** magnetic resonance imaging(MRI)of the brain revealed *** had not undergone any previous eye surgeries or trauma.

关键词： hemodialysis albicans fever

Integrating Neighborhood Geographic Distribution and Social Structure Influence for Social Media User Geolocation

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2513-2532页

作者： meng zhang Xiangyang Luo Ningbo Huang Key Laboratory of Cyberspace Situation Awareness of Henan Province Zhengzhou450001China State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou450001China

Geolocating social media users aims to discover the real geographical locations of users from their publicly available data,which can support online location-based applications such as disaster alerts and local content *** relationship-based methods represent a classical approach for geolocating social ***,geographically proximate relationships are sparse and challenging to discern within social networks,thereby affecting the accuracy of user *** address this challenge,we propose user geolocation methods that integrate neighborhood geographical distribution and social structure influence(NGSI)to improve geolocation ***,we propose a method for evaluating the homophily of locations based on the k-order neighbor-hood geographic distribution(k-NGD)similarity among *** are notable differences in the distribution of k-NGD similarity between location-proximate and non-location-proximate *** this distinction,we filter out non-location-proximate social relationships to enhance location homophily in the social *** better utilize the location-proximate relationships in social networks,we propose a graph neural network algorithm based on the social structure *** algorithm enables us to perform a weighted aggregation of the information of users’multi-hop neighborhood,thereby mitigating the over-smoothing problem of user features and improving user geolocation *** results on real social media dataset demonstrate that the neighborhood geographical distribution similarity metric can effectively filter out non-location-proximate social ***,compared with 7 existing social relationship-based user positioning methods,our proposed method can achieve multi-granularity user geolocation and improve the accuracy by 4.84%to 13.28%.

关键词： User geolocation social media neighborhood geographic distribution structure influence

NLRP3-mediated autophagy dysfunction links gut microbiota dysbiosis to tau pathology in chronic sleep deprivation

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Zoological Research 2024年第4期45卷 857-874页

作者： Na Zhao Xiu Chen Qiu-Gu Chen Xue-Ting Liu Fan Geng meng-meng Zhu Fu-Ling Yan zhi-Jun zhang Qing-Guo Ren Department of Neurology School of MedicineSoutheast UniversityNanjingJiangsu 210009China Department of Neurology Affiliated Zhongda HospitalSoutheast UniversityNanjingJiangsu 210009China

Emerging evidence indicates that sleep deprivation(SD)can lead to Alzheimer’s disease(AD)-related pathological changes and cognitive ***,the underlying mechanisms remain *** the present study,we identified the existence of a microbiota-gut-brain axis in cognitive deficits resulting from chronic SD and revealed a potential pathway by which gut microbiota affects cognitive functioning in chronic *** findings demonstrated that chronic SD in mice not only led to cognitive decline but also induced gut microbiota dysbiosis,elevated NLRP3 inflammasome expression,GSK-3βactivation,autophagy dysfunction,and tau hyperphosphorylation in the *** with the“SD microbiota”replicated the pathological and behavioral abnormalities observed in chronic sleep-deprived ***,both the deletion of NLRP3 in NLRP3-/-mice and specific knockdown of NLRP3 in the hippocampus restored autophagic flux,suppressed tau hyperphosphorylation,and ameliorated cognitive deficits induced by chronic SD,while GSK-3βactivity was not regulated by the NLRP3 inflammasome in chronic ***,deletion of NLRP3 reversed NLRP3 inflammasome activation,autophagy deficits,and tau hyperphosphorylation induced by GSK-3βactivation in primary hippocampal neurons,suggesting that GSK-3β,as a regulator of NLRP3-mediated autophagy dysfunction,plays a significant role in promoting tau ***,gut microbiota dysbiosis was identified as a contributor to chronic SD-induced tau pathology via NLRP3-mediated autophagy dysfunction,ultimately leading to cognitive ***,these findings highlight GSK-3βas a regulator of NLRP3-mediated autophagy dysfunction,playing a critical role in promoting tau hyperphosphorylation.

关键词： Chronic sleep deprivation Tau pathology NLRP3 inflammasome Autophagy GSK-3β Microbiota-gut-brain axis

Central aromatic-core fluorination in non-fullerene acceptor advances binary organic solar cells to a record efficiency of 19.7%

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Science China Materials 2024年第8期67卷 2713-2714页

作者： Ming zhang zhi-Guo zhang State Key Laboratory of Organic/Inorganic Composites Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Organic solar cells(OSCs)hold great promise for the conversion of solar energy into electricity,showing advantages such as lightweight,flexibility,semi-transparency,and solution *** field has witnessed significant adv... 详细信息

关键词： aromatic acceptor transparency

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Developing silicon-based photocathodes for CO_(2) conversion

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Science China Chemistry 2024年第6期67卷 1904-1921页

作者： Weijie Zhuang Miao Kan Tao meng Jinlong zhang Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China Shanghai Engineering Research Center for Multimedia Environmental Catalysis and Resource Utilization East China University of Science and TechnologyShanghai200237China

Photoelectrochemical(PEC)conversion of CO_(2) presents a promising avenue for solar-driven chemical fuel production,with silicon emerging as a cost-effective and high-light-absorbing material pivotal to this *** at exploring opportunities for industrializing PEC CO_(2) reduction(PEC-CO_(2)R)by minimizing reaction energy consumption,enhancing reaction efficiency and selectivity,this review summarizes recent advancements in developing Si-based photocathodes for PEC-CO_(2)*** outlines the fundamental principles,advantages,and limitations of Si photocathodes with key performance *** on this understanding,the strategies to enhance the performance of the PEC-CO_(2)R system,including light absorption,charge separation,and catalytic reactions are categorized as the interfacial modification,active site decoration,and protective layer *** design ideas of this advantageous three-layer structure in promoting the efficiency,stability,and selectivity have been ***,this review scrutinizes the influence of the photocathodic chemical *** review consolidates the mechanism insights and notable breakthroughs of various fuel generation processes within Si-based PEC-CO_(2)R *** this wealth of information offers an up-to-date perspective on the dynamic developments in silicon-based PEC-CO_(2) conversion and underscores the promising pathways toward the sustainable fuel synthesis from pollutant CO_(2).

关键词： photoelectrochemistry solar fuels silicon photocathodes carbon dioxide reduction microenvironment

Enhanced potassium storage of carbon nanofibers as binderfree anodes enabled by coupling ultra-small amorphous Sb_(2)O_(3),graphene modification and sulfur doping

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Rare Metals 2024年第1期43卷 51-64页

作者： Zhao Huang Yu-Kang Lou Lin Peng Yuan Peng meng-meng Wang Ming zhang College of Railway Transportation Hunan University of TechnologyZhuzhou 412007China College of Semiconductors(College of Integrated Circuits) Changsha Semiconductor Technology and Application Innovation Research InstituteHunan UniversityChangsha 410082China Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education College of Semiconductors(College of Integrated Circuits)Hunan UniversityChangsha 410082China

Considering the intrinsic advantages of natural copiousness and cost-effectiveness of potassium resource,potassium-ion batteries(KIBs) are booming as prospective alternatives to lithium-ion batteries(LIBs) in large-scale energy storage scenarios. Nevertheless, lacking desirable electrodes for reversibly hosting the bulky K+hinders the widespread application of KIBs, and it needs to be urgently solved. Hereon, the porous S-doped Sb_(2)O_(3)-graphene-carbon(SAGC) nanofibers are manufactured through an adjustable and facile approach, which involves electrospinning, in situ etching and sulfuration. The synthesized SAGC is featured by the ultra-small amorphous Sb_(2)O_(3) homogeneously wrapped inside the carbon matrix, as well as the co-incorporation of graphene and sulfur. Tentatively,the SAGC nanofiber sheets are applied as binder-free anodes for KIBs, exhibiting a prominent cycling life(256.72 m Ah·g^(-1) over 150 cycles at 100 m A·g^(-1)) and rate·g^(-1) over 100 cycles at 1 A·g^(-1)). The positive synergy among all the active components accounts for the distinguished performances of the SAGC. By reinforcing the tolerability to the swelling stress, producing the valid electrochemical active sites, and promoting the charge transferring for reversible K+uptake, the SAGC finally renders the excellent cyclability, capacity, and rate capability. Moreover, the extrinsic electrochemical pseudocapacitance characteristics induced by the porous carbon substrate elevate the K-storage capacity of the SAGC as well. It is hoped that the conclusions drawn may offer new insights into a direction for the high-performance binderfree KIB anodes.

关键词： S-doped Sb_(2)O_(3)-graphene-carbon Nanofibers Binder-free Anodes Potassium-ion batteries

On-Chip Sub-Picometer Continuous Wavelength Fiber-Bragg-Grating Interrogator

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Photonic Sensors 2024年第1期14卷 73-84页

作者： Yuan ZHUANG Jun ZOU Jiqiang zhang Lu zhang Jiahe zhang Leixin meng Qing YANG Research Center for Humanoid Sensing Zhejiang LabHangzhou 311121China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 310014China State Key Laboratory of Modern Optical Instrumentation College of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsZhejiang UniversityHangzhou 310058China

Miniaturized fiber-Bragg-grating(FBG)interrogators are of interest for applications in the areas where weight and size controlling is important,e.g.,airplanes and aerospace or in-situ *** ultra-compact high-precision on-chip interrogator is proposed based on a tailored arrayed waveguide grating(AWG)on a silicon-on-insulator(SOI)*** on-chip interrogator enables continuous wavelength interrogation from 1544 nm to 1568 nm with the wavelength accuracy of less than 1 pm[the root-mean-square error(RMSE)is 0.73 pm]over the whole wavelength *** chip loss is less than 5 *** 1×16 AWG is optimized to achieve a large bandwidth and a low noise level at each channel,and the FBG reflection peaks can be detected by multiple output channels of the *** fabricated AWG is utilized to interrogate FBG sensors through the center of gravity(CoG)*** validation of an on-chip FBG interrogator that works with sub-picometer wavelength accuracy in a broad wavelength range shows large potential for applications in miniaturized fiber optic sensing systems.

关键词： Fiber optic sensing on-chip interrogator arrayed waveguide grating center of gravity