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Multi-blade rubbing characteristics of the shaft-disk-blade-casing system with large rotation

Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 111-136页

作者： Zhiyuan WU Linchuan zhao Han yan Ge yan Ao CHEN Wenming ZHANG State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Aerospace Systems Engineering Shanghai 201108China

Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery.

关键词： shaft-disk-blade-casing(SDBC) large rotation spin and whirl multi-blade rubbing rotational effect

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不同发酵时间普洱茶的表面增强拉曼光谱鉴别分析

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发光学报 2013年第2期34卷 230-234页

作者：郑玲赵燕平华南师范大学生物光子学研究院&光子中医实验室广东广州510631

发现一种鉴定普洱茶不同发酵时间的快速、简便、科学的方法,通过利用激光共聚焦拉曼光谱仪,采用表面增强拉曼光谱技术(SERS),在600～1 800 cm-1波数段分析了4种发酵时间普洱茶标准品的SERS光谱异同点,发现在655,732,959,1 238 cm-1等较... 详细信息

发现一种鉴定普洱茶不同发酵时间的快速、简便、科学的方法,通过利用激光共聚焦拉曼光谱仪,采用表面增强拉曼光谱技术(SERS),在600～1 800 cm-1波数段分析了4种发酵时间普洱茶标准品的SERS光谱异同点,发现在655,732,959,1 238 cm-1等较为明显的特征峰处存在着明显的差异。研究了普洱茶发酵过程中茶多酚、含氮化合物、有机酸和糖类物质的含量变化规律,通过SERS光谱分析,为鉴定普洱茶的品质提供了一种科学、简便、快捷的光学方法。

关键词：普洱茶表面增强拉曼光谱发酵时间鉴别

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Amorphous Sb/C composite with isotropic expansion property as an ultra-stable and high-rate anode for lithium-ion batteries

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Rare Metals 2024年第5期43卷 2039-2052页

作者： Ze-Zhou yang Cheng-Yi Zhang Yu-Qing Ou Zhi-Kang Su yan zhao Heng-Jiang Cong Xin-ping Ai Jiang-Feng Qian Hubei Key Laboratory of Electrochemical Power Sources College of Chemistry and Molecular SciencesWuhan UniversityWuhan430072China Institute of Technological Sciences Wuhan UniversityWuhan 430072China

Antimony(Sb)is an intriguing anode material for Li-ion batteries(LIBs)owing to its high theoretical capacity of 660 m Ah·g^(-1)and appropriate working potential of~0.8 V(***^(+)/Li).However,just like all alloying materials,the Sb anode suffers from huge volume expansion(230%)during repeated insertion/extraction of Li+ions,resulting in structural deterioration and rapid capacity *** this work,a novel amorphous Sb/C composite with atomically dispersed Sb particles in carbon matrix is prepared via a straightforward high-energy ball milling *** intimate intermixing of amorphous Sb with C provides homogeneous element distribution and isotropic volume expansion during cycling,resulting in persistent structural ***,the disordered structure of amorphous material shortens the diffusion distance of lithium ions/electrons,promoting fast reaction kinetics and rate *** from the aforementioned effects,the amorphous Sb/C exhibits a high reversible capacity of537.4 m Ah·g^(-1)at 0.1 A·g^(-1)and retains 201.0 m Ah·g^(-1)at an ultrahigh current rate of 10.0 A·g^(-1).Even after 1500deep cycles at 2.0 A·g^(-1),the amorphous Sb/C electrode still maintains 86.3%of its initial capacity,which outperforms all existing Sb-based anodes reported so *** analysis further reveals a greatly reduced volume variation of merely 34.6%for the amorphous Sb/C electrode,much lower than that of 223.1%for crystalline Sb *** study presents a new approach to stabilizing Sb-based alloy anodes and contributes to the construction of high-performance amorphous anode materials for LIBs,enabling advanced energy storage.

关键词： Amorphous Sb/C anode Homogeneous element distribution Isotropic volume expansion Ultra-long cycle stability High-rate capability Lithium-ion battery

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Composition optimization and performance prediction for ultra-stable water-based aerosol based on thermodynamic entropy theory

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Defence Technology（防务技术） 2024年第3期33卷 437-446页

作者： Tingting Kang Canjun yan Xinying zhao Jingru zhao Zixin Liu Chenggong Ju Xinyue Zhang Yun Zhang yan Wu College of Chemical Engineering and Materials Science Tianjin University of Science and TechnologyNo.29 13th AvenueEconomic and Technologic Development ZoneTianjin 300457China Tianjin Key Laboratory of Brine Chemical Engineering and Resource Eco-utilization Tianjin University of Science and TechnologyTianjin 300457China College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China

Water-based aerosol is widely used as an effective strategy in electro-optical countermeasure on the battlefield used to the preponderance of high efficiency,low cost and ***,the stability of the water-based aerosol is always unsatisfactory due to the rapid evaporation and sedimentation of the aerosol *** efforts have been devoted to improve the stability of water-based aerosol by using additives with different composition and ***,the lack of the criterion and principle for screening the effective additives results in excessive experimental time consumption and *** the stabilization time of the aerosol is still only 30 min,which could not meet the requirements of the perdurable ***,to improve the stability of water-based aerosol and optimize the complex formulation efficiently,a theoretical calculation method based on thermodynamic entropy theory is *** the factors that influence the shielding effect,including polyol,stabilizer,propellant,water and cosolvent,are considered within *** ultra-stable water-based aerosol with long duration over 120 min is obtained with the optimal fogging agent composition,providing enough time for fighting the electro-optic *** design guideline for choosing the additives with high phase transition temperature and low phase transition enthalpy is also proposed,which greatly improves the total entropy change and reduce the absolute entropy change of the aerosol cooling process,and gives rise to an enhanced stability of the water-based *** theoretical calculation methodology contributes to an abstemious time and space for sieving the water-based aerosol with desirable performance and stability,and provides the powerful guarantee to the homeland security.

关键词： Ultra-stable Water-based aerosol Thermodynamic entropy Composition optimization Performance prediction

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Encouraging Solution to the Problem of Synthesizing Protein α-Thioester

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Chinese Journal of Chemistry 2024年第10期42卷 1114-1120页

作者： Xinliang Liu Zijun Gao Jie zhao Farong Ye ping Huang ping Wang Center for Chemical Glycobiology Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsFrontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringZhangjiang Institute for Advanced StudyShanghai JiaoTongUniversityShanghai 200240China Shenzhen Research Institute of Shanghai Jiao Tong University ShenzhenGuangdong 518057China

Expressed protein ligation(EPL)provides a powerful tool to access large-size proteins with precise *** methods for constructing the critical protein thioester for EPL have predominantly relied on the recombinant intein fusion expressed in Escherichia coli(***).Despite its powerful applications,the expression of thioester derived from eukaryotic protein in *** inherently suffers from its limited solubility,the inactivity of intein,premature hydrolysis and low *** overcome these obstacles,we present herein the facile one-flask synthesis of inaccessible proteinα-thioester via a SUMO-protein-intein(SPI)sandwich *** utility of SUMO enhances the protein fusion yield and solubility,prevents premature hydrolysis and simplifies the purification *** inaccessible protein thioester with internal Cys residues can be readily produced and is compatible with the EPL-desulfurization protocol used to prepare complex proteins,which is otherwise difficult to obtain using traditional *** utility has been highlighted through the synthesis of human granulocyte colony-stimulating factor(G-CSF).

关键词： Desulfurization Glycoproteins Glycopeptides Protein expression Peptide thioester

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Cerebral activation during unilateral clenching in patients with temporomandibular joint synovitis and biting pain： an functional magnetic resonance imaging study

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Chinese Medical Journal 2011年第14期124卷 2136-2143页

作者： zhao yan-ping MA Xu-chen, JIN Zhen LI Ke LIU Gang ZENG Ya-wei Department of Oral Radiology and Center for Temporomandibular Disorders Peking University School and Hospital of StomatologyBeijing 100081 China Department of Radiology 306 Hospital of People's Liberation Army Beijing 100101 China

Background Functional magnetic resonance is a non-invasive method that can examine brain activity and has been widely used in various fields including jaw movement and pain processing. Temporomandibular disorder （TMD） is one of the most frequent facial pain problems. The objective of this study was to investigate the brain activities using functional magnetic resonance imaging （fMRI） during unilateral maximal voluntary clenching tasks in the TMD synovitis patients with biting *** Fourteen TMD synovitis patients with unilateral biting pain and 14 controls were included in the *** biting pain was defined as right molar clenching causing left temporomandibular joint （TMJ） pain. Ipsilateral biting pain was defined as right molar clenching causing right TMJ pain. Symptom Check List-90 （SCL-90） was administered to the patients and controls. Independent sample t-test was used to compare the SCL-90 subscales between the two groups. Unilateral clenching tasks were performed by the patients and controls. Imaging data were analyzed using *** Patients were divided into contralateral TMD biting pain group （n=8） and ipsilateral TMD biting pain group （n=6）. The SCL-90 subscales were significantly different between the two groups for somatization, depression, anxiety,phobic anxiety, and paranoid ideation. Group analysis of the controls demonstrated brain activations in the inferior frontal gyrus, precentral gyrus, middle frontal gyrus, superior temporal gyrus, and insular. The areas of activation were different between right and left clenching task. In TMJ synovitis patients with contralateral or ipsilateral biting pain, the group analysis showed activations in the inferior frontal gyrus, superior temporal gyrus, medium frontal gyrus, precentral gyrus,and anterior cingulate *** The inferior frontal gyrus and precentral gyrus play essential roles during the unilateral clenching *** of anterior cingulate cortex in the syno

关键词： functional magnetic resonance imaging unilateral clenching task inferior frontal gyrus precentral gyrus temporomandibular disorders synovitis

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Role of tumor necrosis factor-like weak inducer of apoptosis （TWEAK）/fibroblast growth factor-inducible 14 （Fnl4） axis in rheumatic diseases

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Chinese Medical Journal 2012年第21期125卷 3898-3904页

作者： ZHU Li-xiu ZHANG Hai-hong MEI Yi-fang zhao yan-ping ZHANG Zhi-yi Department of Rheumatology First Aftiliated ttospital or ttarbinMedical University Harbin Heilongjiang 150001 China Department of Rheumatology Ningde Municipal Hospital FujianCollege of Traditional Chinese Medicine Ningde Fujian 352100China

Tumor necrosis factor （TNF）-Iike weak inducer of apoptosis （TWEAK） is a member of the TNF superfamily of structurally related cytokines and is known to induce proliferation, migration, differentiation, apoptotic celt death, inflammation, and angiogenesis. These physiological processes are induced by the binding of TWEAK to fibroblast growth factor-inducible 14 （Fn14）, a highly inducible cell-surface receptor that is linked to several intracellular signaling pathways, including the nuclear factor-KB （NF-KB） pathway. This review discusses the role of the TWEAK-Fn14 axis in several rheumatic diseases and the potential therapeutic benefits of modulation of the TWEAK-Fn14 pathway.

关键词： tumor necrosis Jactor-like weak inducer of apoptosis fibroblast growth[actor-inducible 14,rheumatic diseases

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A calibration and compensation method for an industrial robot with high accuracy harmonic reducers

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Science China(Technological Sciences) 2024年第3期67卷 725-739页

作者： zhao Yiyang LIU Xun CAO JiaBin LIU JinYu XU yan yan WeiXin School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Computer and Control Engineering Northeast Forestry UniversityHarbin 150040China

Industrial serial robots need high stiffness to keep absolute pose accuracy and meet the requirements in practical applications. However, the weak stiffness feature of robot joints and the payloads affected on robot end-effector, which will also increase the pose error of robot. Especially, the existing calibration methods often consider under no-payload condition without discussing the payload state. In this paper, we report a new industrial serial robot composed by a new harmonic reducer: Model-Y, based on high accuracy and high stiffness, and a kinematic parameter calibration algorithm which is based on a harmonic reducer forcedeformation model. To decrease the accuracy effects of payload, an iterative calibration method for kinematic parameters with payload situation was proposed. Simulation and experiments are conducted to verify the effectiveness of the proposed calibration method using the self-developed industrial serial robot. The results show a remarkably improved accuracy in absolute position and orientation with the robot's payload range. The position mean error has 70% decreased to 0.1 mm and the orientation mean error diminished to less than 0.01° after calibration with compensation. Additionally, online linear and circular tests are carried out to evaluate the position error of the robot during large-scale spatial and low-speed continuous movement. The accuracy is consistent with the previous calibration results, indicating the effectiveness and advantages of the proposed strategy in this article.

关键词： industrial serial robot Model-Y harmonic calibration stiffness model online compensation

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Vibration transfer from underground train to multi-story building:Modelling and validation with in-situ test data

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Underground Space 2024年第6期19卷 301-316页

作者： Li Wang Xin Gao Caiyou zhao ping Wang Zili Li Section of Railway Engineering Delft University of TechnologyStevinweg 12628CN DelftThe Netherlands Key Laboratory of High-speed Railway Engineering(Southwest Jiaotong University) Ministry of EducationChengdu 610031China

Excessive underground train-induced vibration becomes a serious environmental problem in *** investigate the vibration transfer from an underground train to a building nearby,an explicit-integration time-domain,three-dimensional finite element model is *** underground train,track,tunnel,soil layers and a typical multi-story building nearby are all fully coupled in this *** complex geometries involving the track components and the building are all modelled in detail,which makes the simulation of vibration transfer more realistic from the underground train to the *** model is validated with in-situ tests data and good agreements have been achieved between the numerical results and the experimental results both in time domain and frequency *** proposed model is applied to investigate the vibration transfer along the floors in the building and the influences of the soil stiffness on the vibration characteristics of the track-tunnel-soil-building *** is found that the building vibration induced by an underground train is dominant at the frequency determined by the P2 resonance and influenced by the vibration modes of the *** vertical vibration in the building decreases in a fluctuant pattern from the foundation to the top floor due to loss of high frequency contents and local *** vibration levels in different rooms at a same floor can be different due to the different local stiffness.A room with larger space thus smaller local stiffness usually has higher vibration *** soil layers make the tunnel lining and the building have more low frequency *** influence of the soil stiffness on the amplification scale along the floors of the building is found to be nonlinear and frequency-dependent,which needs to be further investigated.

关键词： Railway vibration Underground train Multi-story building vibration Finite element model Dynamic interaction

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Radar false alarm plots elimination based on multi-feature extraction and classification

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 83-92页

作者： Cheng Yi zhao yan Yin Peiwen School of Control Science and Engineering Tiangong UniversityTianjin 300387China Tianjin Key Laboratory of Intelligent Control of Electrical Equipment Tianjin 300387China

Caused by the environment clutter,the radar false alarm plots are *** false alarm points has always been a key issue in Radar plots *** this paper,a radar false alarm plots elimination method based on multi-feature extraction and classification is proposed to effectively eliminate false alarm ***,the density based spatial clustering of applications with noise(DBSCAN)algorithm is used to cluster the radar echo data processed by constant false-alarm rate(CFAR).The multi-features including the scale features,time domain features and transform domain features are ***,a feature evaluation method combining pearson correlation coefficient(PCC)and entropy weight method(EWM)is proposed to evaluate interrelation among features,effective feature combination sets are selected as inputs of the ***,False alarm plots classified as clutters are *** experimental results show that proposed method can eliminate about 90%false alarm plots with less target loss rate.

关键词： radar plots elimination density based spatial clustering of applications with noise multi-feature extraction classifier

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