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Rare Metals 2022年第8期41卷 2886-2893页

作者： Dong-Ming Jin Zhen-Hua wang Jin-Feng Li Ben Niu qing wang Engineering Research Center of High Entropy Alloy Materials(Liaoning Province) Key Laboratory of Materials Modification by LaserIon and Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Institute of Materials China Academy of Engineering PhysicsMianyang621908China

The present work investigated the formation of coherent body-centered-cubic(BCC)/B2 microstructure in Al-Ti-Zr-Nb-Ta-Cr/Mo refractory high-entropy alloy system,in which three alloys with the composition of Al_(2)Ti_(6) Zr_(2)Nb_(3)Ta_(2)(Cr/Mo)_(1)were *** as-cast alloy ingots were homogenized at 1573 K for 2 h and then aged at different temperatures for 24 *** is found that the BCC/B2 coherent microstructure with cuboidal BCC nanoprecipitates into the B2 matrix would be formed in873 K-aged Al_(2)Ti_(6) Zr_(2)Nb_(3)Ta_(2)Cr_(0.5)Mo_(0.5)alloy with half Cr and half Mo,which is ascribed to a moderate lattice misfit(ε=0.94%)between BCC and B2 *** is due to the special coherent microstructure that results in a prominent mechanical property with the highest compressive yield strength(σ_(YS)=1314 MPa)and good plasticity among these alloys,while coarse Cr2 Ti and Zr_(5)Al_(3)particles are existed in 873 K-aged alloy with *** 1073 K aging,all these alloys with Cr_(1),Cr_(0.5)Mo_(0.5)and Mo_(1)consist of BCC,B2 and Zr_(5)Al_(3),in which BCC/B2 coherent microstructure is *** strengthening mechanism of BCC/B2 coherent microstructure in 873 K-aged alloy with Cr_(0.5)Mo_(0.5)was also discussed.

关键词： High entropy alloys Coherent precipitation Microstructure Lattice misfit Precipitation strengthening

A Criterion for Stability of Synchronization and Application to Coupled Chua's Systems

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Communications in Theoretical Physics 2009年第3期51卷 475-478页

作者： wang Hai-Xia LU Qi-Shao wang qing-Yun School of Science Nanjing University of Science and Technology Nanjing 210094 China School of Science Beihang University Beijing 100191 China School of Statistics and Mathematics Inner Mongolia College Huhhot 010051 China

We investigate synchronization in an array network of nearest-neighbor coupled chaotic oscillators. By using of the Lyapunov stability theory and matrix theory, a criterion for stability of complete synchronization is deduced. Meanwhile, an estimate of the critical coupling strength is obtained to ensure achieving chaos synchronization. As an example application, a model of coupled Chua＇s circuits with linearly bidirectional coupling is studied to verify the validity of the criterion.

关键词： synchronization Lyapunov function approach Lipschitz condition

Emplacement age and tectonic implications of the brecciated limestone at the edge of the Longmenshan klippe

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Science China Earth Sciences 2016年第3期59卷 590-600页

作者： XUE Zhen Hua SHANG qing Hua JIANG Wen Ying wang qing Chen LI Shuang Jian State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Betljing 100029 Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China University of Chinese Academy of Sciences Beijing 100049 China Institute of Petroleum Exploration and Development China Petroleum and Chemical Corporation Beijing 100083 China

The Longmenshan thrust belt(LMTB) is one of the best natural laboratories for thin-skinned tectonics and has developed a series of NE-SW trending fold-and-thrust structures represented by a series of nappes and klippes, exemplified by the Tangbazi and Bailuding klippe. However, the timing and emplacement mechanism of these klippes are still in dispute. Three possible mechanisms have been proposed:(1) a Mesozoic-Cenozoic southeastward thrusting,(2) a Cenozoic gravity gliding, and(3) glacial deposition. Almost all of these klippes are tectonic and overlaid on folded Late Triassic sandstone except the Tangbazi klippe, which is located in the center of the LMTB and has a narrow tail extending southeastward and covering Jurassic-Quaternary rocks. This geometric relationship is considered the most important stratigraphic evidence to support the post-Cenozoic emplacement of the Longmenshan klippe. Our structural and petrological observations show that the rocks at the front of the Tangbazi and Bailuding structures are brecciated limestone, which is assumed to have been generated by a gravitational collapse and is not characteristic of the massive Permian strata. Artemisia pollen, which has been exclusively recognized in post-Late Eocene strata in Central Asia, was found in the matrix of this brecciated limestone. Therefore, our discovery indicates that the brecciated limestone was deposited after the Late Eocene rather than during the Permian as annotated on the geological map. In contrast, unbrecciated, massive Permian limestone overlaid on the folded Late Triassic rocks. Hence, the anomalous relationship of Permian strata overlaying Late Triassic rocks cannot be evidence of Cenozoic emplacement. According to currently recognized bulk strata relationships, we can only be sure that the klippe was emplaced in the post Late Triassic. The petrological characteristics of the brecciated limestone show that it was crumbled before the re-sedimentation of the breccia, implying tha

关键词： Longmenshan thrust belt Klippe Artemisia Brecciated limestone Thin-skinned structure

Hot Deformation Behavior of Nickel-Based Superalloy GH4720Li

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Journal of Iron and Steel Research International 2011年第10期18卷 59-65页

作者： QU Jing-long BI Zhong-nan DU Jin-hui wang Min-qing wang qing-zeng ZHANG Ji Central Iron and Steel Research Institute Beijing 100081 Chinas Special Steel Multi-Division Baoshan Iron and Steel Co Ltd Shanghai 200940 China

The hot deformation characteristics of GH4720Li alloy were studied at the temperature of 1 100--1 170 ℃ and strain rate of 0.01--1 s -1 using Gleeble hot compression tests. True stress-true strain curves and deformation microstructures were investigated. Constitutive equation was established using the hyperbolic law. Processing map for hot working was also developed on the basis of the variations of efficiency of power dissipation with temperature and strain rate. The results show that dynamic recrystallization is the dominant softening mechanism during hot deformation. Fully recrystallized grain is obtained at strain of 0. 7 above 1 130 ℃, and coarsening occurs above 1 150 ℃. The mean deformation activation energy is determined to be 512 kJ/mol. According to the low activation energy value, high dissipation efficiency parameter and fine recrystallized microstructure, 1 130 ℃ is chosen as the hot working temperature for GH4720Li alloy.

关键词： hot deformation GH4720Li alloy constitutive equation processing map

Theoretical analyses of stock correlations affected by subprime crisis and total assets: Network properties and corresponding physical mechanisms

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Chinese Physics B 2019年第10期28卷 609-621页

作者： Shi-Zhao Zhu Yu-qing wang Bing-Hong wang School of Business University of Shanghai for Science and TechnologyShanghai 200093China School of Mechanical Engineering Hefei University of TechnologyHefei 230009China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China

In the field of statistical mechanics and system science, it is acknowledged that the financial crisis has a profound influence on stock market. However, the influence of total asset of enterprise on stock quote was not considered in the previous studies. In this work, a modified cross-correlation matrix that focuses on the influence of total asset on stock quote is introduced into the analysis of the stocks collected from Asian and American stock markets, which is different from the previous studies. The key results are obtained as follows. Firstly, stock is more greatly correlated with big asset than with small asset. Secondly, the higher the correlation coefficient among stocks, the larger the eigenvector is. Thirdly, in different periods, like the pre-subprime crisis period and the peak of subprime crisis period, Asian stock quotes show that the component of the third eigenvector of the cross-correlation matrix decreases with the asset of the enterprise ***, by simulating the threshold network, the small network constructed by 10 stocks with large assets can show the large network state constructed by 30 stocks. In this research we intend to fully explain the physical mechanism for understanding the historical correlation between stocks and provide risk control strategies in the future.

关键词： complex networks total assets subprime crisis stock correlations

Effect of the partial substitution of Mg by Al on the crystal structure and hydrogenation behavior of La_2Mg_(17)

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Rare Metals 2007年第4期26卷 347-351页

作者： ZHANG qing＇ an wang Changchun SI Tingzhi School of Materials Science and Engineering Anhui University of Technology Maanshan 243002 China

The effect of the partial substitution of Mg by A1 on the crystal structure of La2Mg17 has been investigated. It was found that the LaEMgl7 phase disappears after the partial substitution of Mg by Al. The LaE（***0.1）17 alloy contains La（Mg,AI）12 and La（Mg,Al）2. Further increasing the Al content, the La2（Mg0.8Al0.2）17 alloy consists of La（Mg,Al）12, La（Mg,Al）2, and Mg. The La（Mg0.93Al0.07）12 phase in the La2（Mg0.9Al0.1）17 alloy crystallizes with the ThMn12-type structure in space group 14/mmm （No. 139）. The lattice parameters were determined to be a = 1.03246（7） nm and c = 0.59410（6） nm. In the ThMn12-type structure, AI atoms occupy 8f site but the A1 content is limited. Moreover, the hydrogenation character- istics have also been compared. La2Mgl7 decomposes into LaH3 and MgH2 under hydrogen, but the La（Mgo.93Alo.o7）12 phase can be hydrogenated into LaH3, MgH2, and La3Al11 at 473 K.

关键词： intermetallic compound crystal structure hydrogenation characteristic X-ray diffraction

Hilbert-Schmidt-Hankel norm model reduction for matrix second-order linear systems

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控制理论与应用（英文版） 2011年第4期9卷 571-578页

作者： qing wang Tongke ZHONG Ngai WONG qingyang wang School of information Science and Technology Sun Yat-Sen University Guangzhou Guangdong 510275 China School of Electric Power South China University of Technology Guangzhou Guangdong 510640 China Department of Electrical and Electronic Engineering The University of Hong Kong Pokfulam Road Hong Kong China College of Automation and Engineering South China University of Technology Guangzhou Guangdong 510640 China

This paper considers the optimal model reduction problem of matrix second-order linear systems in the sense of Hilbert-Schmidt-Hankel norm, with the reduced order systems preserving the structure of the original systems. The expressions of the error function and its gradient are derived. Two numerical examples are given to illustrate the presented model reduction technique.

关键词： Model reduction Matrix second-order linear system Hilbert-Schmidt-Hankel norm Gradient

Composition formulas of Ti alloys derived by interpreting Ti-6Al-4V

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Science China(Technological Sciences) 2021年第8期64卷 1732-1740页

作者： LIU TianYu ZHANG Shuang wang qing MIN XiaoHua DONG Chuang Key Laboratory for Materials Modification by Laser Ion and Electron BeamsDalian University of TechnologyMinistry of EducationDalian116024China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian116028China

Titanium alloys are composed ofαandβphases and are classified as nearα,dual-phaseα+β,andβ*** study attempts to derive their general composition formulas within the cluster-plus-glue-atom model by interpreting Ti-6A1-4V and other popular dual-phaseα+βTi alloy s with well-established chemical *** model identifiedαmolecule-like structural unit that covers onlyαnearest-neighbor cluster along withαfew next-neighbor glue atoms,which can be represented as"[cluster](glue atoms)x".The structural units of theαandβphases in Ti-6Al-4V,α-[Al-Ti_(12)](AlTi_(2)),andβ-[Al-Ti_(14)](V2Ti),were derived first and were in an unusual unit ratio of about 2.33:*** obtain an alloy composition formula that satisfied this unit ratio,the two clusters were treated as hard spheres of different radii and packed according to the clusterplusglueatom *** calculations determined that the Ti-6A1-4V alloy unit is composed of 12α-[Al-Ti_(12)](AlTi_(2))and 5β-[Al-Ti_(14)](V2Ti)units(Ti-6.05A1-3.94V wt.%),with the fractional volume of theβphase being 32.5 vol.%,which is in agreement with experimental ***,we describe how the chemical formulas of theαand p phases explain the high temperature near-a alloys(such as Ti-1100,[Al-(Ti_(0.97)Zr_(0.03))_(12)](Al_(0.67)Si_(0.12)Sn_(0.18)Mo_(0.03))_(1.01)Ti_(1.99))and high-strengthβ-Ti alloys(such as Ti-5553,[Al-Ti_(14)](Al_(0.24)Fe_(0.03)Cr_(0.20)-Mo_(0.18)V0.35)_(2.45)Ti_(0.55)),respectively.

关键词： Ti-6Al-4V titanium alloys chemical formula cluster-plus-glue-atom model cluster-resonance model

Real-time arrival picking of rock microfracture signals based on convolutional-recurrent neural network and its engineering application

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 761-777页

作者： Bing-Rui Chen Xu wang Xinhao Zhu qing wang Houlin Xie State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Accurately picking P-and S-wave arrivals of microseismic(MS)signals in real-time directly influences the early warning of rock mass failure.A common contradiction between accuracy and computation exists in the current arrival picking ***,a real-time arrival picking method of MS signals is constructed based on a convolutional-recurrent neural network(CRNN).This method fully utilizes the advantages of convolutional layers and gated recurrent units(GRU)in extracting short-and long-term features,in order to create a precise and lightweight arrival picking ***,the synthetic signals with field noises are used to evaluate the hyperparameters of the CRNN model and obtain an optimal CRNN *** actual operation on various devices indicates that compared with the U-Net method,the CRNN method achieves faster arrival picking with less performance *** application of large underground caverns in the Yebatan hydropower station(YBT)project shows that compared with the short-term average/long-term average(STA/LTA),Akaike information criterion(AIC)and U-Net methods,the CRNN method has the highest accuracy within four sampling points,which is 87.44%for P-wave and 91.29%for S-wave,*** sum of mean absolute errors(MAESUM)of the CRNN method is 4.22 sampling points,which is lower than that of the other *** the four methods,the MS sources location calculated based on the CRNN method shows the best consistency with the actual failure,which occurs at the junction of the shaft and the second ***,the proposed method can pick up P-and S-arrival accurately and rapidly,providing a reference for rock failure analysis and evaluation in engineering applications.

关键词： Rock mass failure Microseismic event P-wave arrival S-wave arrival Deep learning

Silicon-carbide fiber-reinforced polymer electrolyte for all-solid-state lithium-metal batteries

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Rare Metals 2022年第11期41卷 3774-3782页

作者： Wen-qing Wei Bing-Qiang Liu Yan-qing wang Kai Yan Hao Zhang Yu-Song Qi School of Mechanical and Automation Weifang UniversityWeifang261061China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo315201China College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdao266590China School of Mechanical and Electrical Weifang University of Science and TechnologyShouguang262700China

Silicon carbide(SiC) with various morphologies was employed as reinforcing fillers for poly(ethylene oxide)(PEO)-based solid polymer electrolytes(SPEs).Specific ally,the SiC nanoparticles with an average size of 5-10 μm endow a significant enhancement of the interaction between carbon atoms for the fillers and the oxygen atoms from the PEO-lithium bis(trifluoromethanesulfonyl)imide(LiTFSI) matrix,which provides rapid transport channels for mobile Li+and enhances the mechanical strength of *** SPEs reinforced with one-dimensional SiC nanoparticles exhibit superior Li^(+)conduction,good mechanical property,and uniform Li ***,a dendrite-free plating of lithium for 0.58 mAh at 0.1 mA·cm^(-2) and excellent cycle stability at various current densities for 250 h are achieved in Li/Li symmetric cells using SPEs electrolytes with 5.0 wt% SiC ***,the LiFePO_(4)/Li full cells assembled using SPEs electrolytes with 5.0 wt% SiC nanoparticles provide a capacity of 151.5 mAh·g^(-1) at 0.1 mA·cm^(-2)(55℃),and maintained a Coulombic efficiency of 99% for 120 cycles.

关键词： All-solid-state batteries Polymer electrolyte Ionic conductivity Mechanical property Lithium dendrites