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Unveiling the dynamic instability mechanism of microstructure transformation in faceted oxide eutectic composite ceramics

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Journal of Materials Science & Technology 2023年第13期144卷 224-234页

作者： Haijun Su Yuan Liu qun Ren Zhonglin Shen Min Guo xi Li Jun Zhang Lin Liu Hengzhi fu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China Department of Material Science and Engineering Shanghai UniversityShanghai 200072China

Microstructure control is a great challenge in the high-temperature gradient directional solidification of eutectic composite ceramics due to the complex solidification ***,the microstructure trans-formation of faceted Al_(2)O_(3)/Er_(3)Al_(5)O_(12) thermal emission eutectic composite ceramics is explored over wide ranges of compositions(13.5 mol%-22.5 mol%Er_(2)O_(3))and solidification rates(2-200μm/s).Entirely cou-pled eutectics with primary phases suppressed are fabricated and the coupled zone is broadened in a wide range of 15.5 mol%-22.5 mol%Er_(2)O_(3) at low solidification *** competitive growth between eutectic and dendrite is evaluated on the basis of the maximum interface temperature *** ad-dition,the mechanisms of irregular eutectic spacing selection and adjustment under different solidifi-cation rates are revealed based on Magnin-Kurz model.A successful prediction of lamellar to rod-like eutectics is achieved associated with the dynamic instability of lamellar eutectic and the corresponding enlarged coexistence region is mapped based on the interface *** to the well mi-crostructure tailoring,the flexural strength of Al_(2)O_(3)/Er_(3)Al_(5)O_(12) eutectic composite ceramics has improved from 508 MPa up to 1800 MPa due to the refined eutectic spacing with low *** eutectic composite ceramics show strong selective optical absorption and the intensity increases with the refin-ing *** as-designed Al_(2)O_(3)/Er_(3)Al_(5)O_(12) composites with microstructural tailoring have great potential as integrations of structural and functional materials.

关键词： Directional solidification Laser floating zone melting Al_(2)O_(3)/Er_(3)Al_(5)O_(12)eutectic composite ceramics Eutectic growth mechanism Microstructure transformation

Coupling for Markovian switching jump-diffusions

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Applied Mathematics(A Journal of Chinese Universities) 2013年第2期28卷 204-216页

作者： xi fu-bao School of Mathematics Beijing Institute of Technology

This work is concerned with coupling for a class of Markovian switching jump-diffusion *** processes under consideration can be regarded as a number of jump-diffusion processes modulated by a Markovian switching *** t... 详细信息

关键词： Jump-diffusion Markovian switching successful coupling order-preserving coupling.

Invariant Measure for the Markov Process Corresponding to a PDE System

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Acta Mathematica Sinica,English Series 2005年第3期21卷 457-464页

作者： fu Bao xi Department of Mathematics Beijing Institute of Technology Beijing 100081 P. R. China

In this paper, we consider the Markov process （X^∈（t）, Z^∈（t）） corresponding to a weakly coupled elliptic PDE system with a small parameter ∈ 〉 0. We first prove that （X^∈（t）, Z^∈（t）） has the Feller continuity by the coupling method, and then prove that （X^∈（t）, Z^∈（t）） has an invariant measure μ^∈（·） by the Foster-Lyapunov inequality. Finally, we establish a large deviations principle for μ^∈（·） as the small parameter e tends to zero.

关键词： Feller continuity Coupling Invariant measure Foster-Lyapunov inequality Large deviations

Analysis of a permeable interface crack in elastic dielectric/piezoelectric bimaterials

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Acta Mechanica Sinica 2007年第6期23卷 681-687页

作者： qun Li Yiheng Chen School of Aerospace,xi’an Jiaotong University,xi’an 710049,China School of Aerospace Xi’an Jiaotong University Xi’an 710049 China

A permeable interface crack between elasticdielectric material and piezoelectric material is studied basedon the extended Stroh’s *** by strong engi-neering demands to design new composite materials,theauthors perform numerical analysis of interface crack tip sin-gularities and the crack tip energy release rates for 35 typesof dissimilar bimaterials,respectively,which are constructedby five kinds of elastic dielectric materials:Epoxy,Poly-mer,Al;O;.SiC,and Si;N;and seven kinds of practicalpiezoelectric ceramics:PZT-4,BaTiO;,PZT-5H,PZT-6B,PZT-7A,P-7,and PZT-PIC 151,*** elasticdielectric material with much smaller permittivity than com-mercial piezoelectric ceramics is treated as a special trans-versely isotropic piezoelectric material with extremely *** present investigation shows that thestructure of the singular field near the permeable interfacecrack tip consists of three singularities:r;and r;,which is quite different from that in the impermeable inter-face *** can be concluded that different far field load-ing cases have significant influence on the near-tip fracturebehaviors of the permeable interface *** on thepresent theoretical treatment and numerical analysis,the elec-tric field induced crack growth is well explained,which pro-vides a better understanding of the failure mechanism inducedfrom interface crack growth in elastic dielectric/piezoelectricbimaterials.

关键词： Elastic dielectric Piezoelectric Permeable Interface crack Singularity Energy release rate

Study on the Free-Surface Flow of Silicon Melt in the Crucible

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Rare Metals 1989年第1期9卷 39-44页

作者： Li, Yingchun Wan, qun fu, Qin General Research Inst for Non-ferrous Metals China

The flow of a free-surface layer melt in a crucible has been studied by observing the movement of the particle on the free-surface of a silicon melt. A new view on the transportation of impurities in the melt is presented. The experimental results verify the effect of the free-surface layer melt's flow on the distribution of impurities in the as-grown crystal.

关键词： Crystals Growing

Chinese Word Segmentation via BiLSTM+Semi-CRF with Relay Node

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Journal of Computer Science & Technology 2020年第5期35卷 1115-1126页

作者： Nuo qun Hang Yan xi-Peng Qiu Xuan-Jing Huang School of Computer Science Fudan UniversityShanghai 200433China Shanghai Key Laboratory of Intelligent Information

Semi-Markov conditional random fields(Semi-CRFs)have been successfully utilized in many segmentation problems,including Chinese word segmentation(CWS).The advantage of Semi-CRF lies in its inherent ability to exploit properties of segments instead of individual elements of *** its theoretical advantage,Semi-CRF is still not the best choice for CWS because its computation complexity is quadratic to the sentenced *** this paper,we propose a simple yet effective framework to help Semi-CRF achieve comparable performance with CRF-based models under similar computation ***,we first adopt a bi-directional long short-term memory(BiLSTM)on character level to model the context information,and then use simple but effective fusion layer to represent the segment ***,to model arbitrarily long segments within linear time complexity,we also propose a new model named *** direct modeling of segments makes the combination with word features easy and the CWS performance can be enhanced merely by adding publicly available pre-trained word *** on four popular CWS datasets show the effectiveness of our proposed *** source codes and pre-trained embeddings of this paper are available on https://***/fastnlp/fastNLP/.

关键词： Semi-Markov conditional random field(Semi-CRF) Chinese word segmentation bi-directional long short-term memory deep learning

Imperative for long-term management and surveillance in Kawasaki disease

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World Journal of Clinical Cases 2025年第4期13卷 61-63页

作者： Yan Pan fu-Yong Jiao Department of Pediatrics The First Affiliated Hospital of Yangtze UniversityJingzhou 434000Hubei ProvinceChina Shaanxi Kawasaki Disease Diagnosis and Treatment Center Children’s HospitalShaanxi Provincial People’s Hospital of Xi’an Jiaotong UniversityXi’an 710000Shaanxi ProvinceChina

Kawasaki disease(KD)is a significant pediatric vasculitis known for its potential to cause severe coronary artery *** the effectiveness of initial treatments,such as intravenous immunoglobulin,KD patients can experience long-term cardiovascular issues,as evidenced by a recent case report of an adult who suffered a ST-segment elevation myocardial infarction due to previous KD in the World Journal of Clinical *** editorial emphasizes the critical need for long-term management and regular surveillance to prevent such *** drawing on recent research and case studies,we advocate for a structured approach to follow-up care that includes routine cardiac evaluations and preventive measures.

关键词： Kawasaki disease Long-term management Coronary artery aneurysm Surveillance Preventive care

Review of cylinder block/valve plate interface in axial piston pumps: Theoretical models,experimental investigations, and optimal design

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Chinese Journal of Aeronautics 2021年第1期34卷 111-134页

作者： Jiang'ao ZHAO Yongling fu Jiming MA Jian fu qun CHAO Yan WAng School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Laboratory of Aerospace Servo Actuation and Transmission Beihang UniversityBeijing 100191China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

Axial piston pumps have been widely used in aircraft hydraulic systems to supply the system with pressurized fluid. The continuous improvement of the aircraft performance has put forward the demand on aviation piston pumps for high power density, safety, and reliability. The lubricating interfaces in axial piston machines are the key design issue that greatly determines the pump performance and service life. The cylinder block/valve plate interface is one of these critical lubricating interfaces and has received considerable attention from many researchers in the last half century. This study aims to review the state-of-the-art literature on the cylinder block/valve plate interface comprehensively and systematically. First, we introduce various theoretical models developed to investigate the lubrication behaviors of the interface and compare them in terms of their assumptions and limitations. Second, the experimental studies on the cylinder block/valve plate interface are presented comprehensively, where the involved test rigs are divided into three types according to their fidelity levels and measurement functionality. Third, we summarize some typical approaches of structure optimization, surface shaping, and surface strengthening, which help improve the load-carrying and anti-wear capacities of the interface under severe operating conditions. Finally, the challenges and future trends of the cylinder block/valve plate interface research are discussed briefly.

关键词： Axial piston pump Cylinder block/valve plate interface Theoretical model Test rig Optimization methods

Shu-szi Sin: A Chinese pioneer biologist, ancient agronomist, and educator

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Protein & Cell 2021年第7期12卷 515-517页

作者： qun xie Yan-ping Cheng Lei fu Teacher Education College Zhejiang Normal UniversityJinhua 321000China

Shu-szi Sin(辛树枳,1894-1977)(Fig.1),a Chinese pioneer biologist and ancient agronomist,initiated the earliest scientific biological investigation of the Dayao mountain in both Guangxi and Guangdong provinces,discovering more than 20 new species that have been acknowledged *** was one of the founders and initiators of the China Botanical Society and the China Zoological *** was also a great educator Among one of those who first introduced the scientific method into agricultural history research,*** helped to set up the National Northwest Agriculture and Forestry College(now Northwest A&F University)and the Lanzhou *** devoted himself to the development of higher education in Northwest China.

关键词： China. Northwest devoted