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Optimizing Strength and Ductility of Titanium Alloys by Oxygen: Review and Prospect

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Chinese Journal of Structural Chemistry 2020年第4期39卷 615-622页

作者： cai ze-Yun LI Kun XIE Guo-Qiang School of Materials Science and Engineering Harbin Institute of TechnologyShenzhen 518055China

The traditional strengthening elements of titanium alloys include Al,Mo,V,etc.,however,the high cost and toxicity of these elements put a limit on their further applications for *** light elements such as oxygen are hopeful replacement due to high *** is recognized that the oxygen enhances the strength but pays the price of brittleness,thus the amount of oxygen is ***,recent study results indicated that excess oxygen can keep high ductility together with high strength of *** paper reviews the influence and the mechanism of oxygen on the strength and ductility of titanium alloys,and provides a new perspective for the strengthening method of titanium alloys.

关键词： oxygen strength ductility titanium alloy

Synchronization and Exponential Estimates of Complex Networks with Mixed Time-varying Coupling Delays

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International Journal of Automation and computing 2009年第3期6卷 301-307页

作者： Yang Dai Yun-ze cai Xiao-Ming Xu Department of Automation Shanghai Jiao Tong University Shanghai 200240 PRC University of Shanghai for Science and Technology Shanghai 200093 PRC Shanghai Academy of Systems Science Shanghai 200093 PRC

Exponential estimates and sufficient conditions for the exponential synchronization of complex dynamical networks with bounded time-varying delays are given in terms of linear matrix inequalities （LMIs）. A generalized complex networks model involving both neutral delays and retarded ones is presented. The exponential synchronization problem of the complex networks is converted equivalently into the exponential stability problem of a group of uncorrelated delay functional differential equations with mixed timevarying delays. By utilizing the free weighting matrix technique, a less conservative delay-dependent synchronization criterion is derived. An illustrative example is provided to demonstrate the effectiveness of the proposed method.

关键词： Complex networks synchronization exponential estimates neutral delay time-varying delay.

A multi-fidelity prediction model for vertical bending moment and total longitudinal stress of a ship based on composite neural network

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Journal of Hydrodynamics 2023年第1期35卷 27-35页

作者： cai-xia Jiang Yu-bo Liu Zi-yuan Wang Shuai Chen Sheng-ze cai Qi Gao Xue-ming Shao Science and Technology on Advanced Composites in Special Environments Key Laboratory Harbin Institute of TechnologyHarbin150001China China Ship Scientific Research Center Wuxi214082China School of Aeronautics and Astronautics Zhejiang UniversityHangzhou310027China College of Control Science and Engineering Zhejiang UniversityHangzhou310027China

In ship engineering,the prediction of vertical bending moment(VBM)and total longitudinal stress(TLS)during ship navigation is of utmost *** this work,we propose a new prediction paradigm,the multi-fidelity regression model based on multi-fidelity data and artificial neural network(MF-ANN).Specifically,an ANN is used to learn the fundamental physical laws from low-fidelity data and construct an initial input-output *** predicted values of this initial model are of low accuracy,and then the high-fidelity data are utilized to establish a correction model that can correct the low-fidelity prediction ***,the overall accuracy of prediction can be improved *** feasibility of the multi-fidelity regression model is demonstrated by predicting the VBM,and the robustness of the model is evaluated at the same *** prediction of TLS on the deck indicates that just a small amount of high-fidelity data can make the prediction accuracy reach a high level,which further illustrates the validity of the proposed MF-ANN.

关键词： Artificial neural network multi-fidelity vertical bending moment total longitudinal stress

POLYMERIZATION OF OCTAMETHYLCYCLOTETRASILOXANE WITH HEXAMETHYLDISILAZYL-LITHIUM AS INITIATOR

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Chinese Journal of Polymer Science 2001年第1期19卷 7-11页

作者： Zhijie Zhang Ning Zhou cai-hong Xu ze-min Xie Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

This work focused on the anionic polymerization of octamethylcyclotetrasiloxane (D-4, D = Me2SiO2/2) initiated by a new kind of initiator hexamethydisilazyl-lithium (MMNLi). Si-29-NMR spectroscopy and gas chromatography (GC) were used to characterize the polymerization products. The process was accelerated by adding a small amount of high activity monomer D-3 and by raising the polymerization temperature. At the end of polymerization more than 95% of the monomer was converted to polymer and only a very small amount of D-4 and D-5 remained in the polymers.

关键词： high purity polydimethylsiloxane octamethylcyclotetrasiloxane hexamethyldisilazyl-lithium anionic polymerization

An experimental study on the velocity fluctuations generated by the flow past fixed spheres

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Journal of Hydrodynamics 2022年第2期34卷 214-225页

作者： Ling-xin Zhang Xin-sheng Cheng ze-cai Zhou Qi Gao Xue-ming Shao State Key Laboratory of Fluid Power and Mechatronic Systems Department of MechanicsZhejiang UniversityHangzhou310027China

We perform a series of experiments to study the velocity fluctuations generated by the flow past fixed *** particle image velocimetry(PIV)is carried out to characterize the properties of the liquid *** fluctuation induced by the spheres can be decomposed into the temporal fluctuation and the spatial fluctuation,which represent the contribution of flow instability and spatial inhomogeneity,*** particularly,we focus on the contributions of temporal fluctuations and spatial fluctuations between low and high Reynolds *** low Reynolds number(20200,but not for Re<*** ending scale is aroundλ=0.5d and decreases slightly as Re increases.

关键词： Multiphase flow turbulence modulation particle image velocimetry(PIV)

Holographic Schwinger effect in a rotating strongly coupled medium

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Chinese Physics C 2022年第10期46卷 178-183页

作者： Yi-ze cai Rui-Ping Jing Zi-Qiang Zhang School of Mathematics and Physics China University of GeosciencesWuhan 430074China

We perform a potential analysis on the holographic Schwinger effect in a rotating deformed AdS blackhole *** calculate the total potential of a quark-antiquark(QQ)pair in an external electric field and evaluate the critical electric field from Dirac-Born-Infeld *** is shown that the inclusion of angular velocity decreases the potential barrier,thus enhancing the Schwinger effect,which contrasts with the effect of the confining ***,increasing the angular velocity decreases the critical electric field,above which these pairs are produced freely without ***,we conclude that QQ pair production would be easier in a rotating medium.

关键词： Schwinger effect AdS/CFT correspondence quark gluon plasma

Study on Robust H_∞ Filtering in Networked Environments

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International Journal of Automation and computing 2011年第4期8卷 465-471页

作者： Yun-ze cai Li Xu Jian-Xi Gao Xiao-Ming Xu Department of Automation Shanghai Jiao Tong University Shanghai 200240 PRC Shanghai Academy of Systems Science Shanghai 200093 PRC Department of Electronics and Information Systems Akita Prefectural University Yuri-Honjo Akita 015 0055 Japan University of Shanghai for Science and Technology Shanghai 200093 PRC

This paper is concerned with the robust H ∞ filter problem for networked environments, which are subject to both transmission delay and packet dropouts randomly. By employing random series which have Bernoulli distributions taking value of 0 or 1, the data transmission model is obtained. Based on state augmentation and stochastic theory, the sufficient condition for robust stability with H ∞ constraints is derived for the filtering error system. The robust filter is designed in terms of feasibility of one certain linear matrix inequality （LMI）, which is formed by adopting matrix congruence transformations. A numerical example is given to show the effectiveness of the proposed filtering method.

关键词： Robust filtering networked environments transmission delay packet dropouts linear matrix inequality (LMI).

Three-Dimensional Hermite–Bessel–Gaussian Soliton Clusters in Strongly Nonlocal Media

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Chinese Physics Letters 2012年第12期29卷 97-101页

作者： JIN Hai-Qin LIANG Jian-Chu cai ze-Bin LIU Fei YI Lin School of Physics Huazhong University of Science and TechnologyWuhan 430074 School of Physics and Electronic Information Hubei University of EducationWuhan 430205 Department of Electronic Science Huizhou UniversityGuangdong 516001 Scientific Research Department Air Force Early Warning AcademyWuhan 430019 Department of Physics Hubei Normal UniversityHuangshi 430205

We analytically and numerically demonstrate the existence of Hermite-Bessel-Gaussian spatial soliton clusters in three-dimensional strongly nonlocal *** is found that the soliton clusters display the vortex,dipole azimuthon and quadrupole azimuthon in geometry,and the total number of solitons in the necklaces depends on the quantum number n and m of the Hermite functions and generalized Bessel *** numerical simulation is basically identical to the analytical solution,and white noise does not lead to collapse of the soliton,which confirms the stability of the soliton *** theoretical predictions may give new insights into low-energetic spatial soliton transmission with high fidelity.

关键词： soliton Bessel Gaussian

Holographic Schwinger effect in spinning black hole backgrounds

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Chinese Physics C 2024年第1期48卷 165-172页

作者：蔡镒泽张自强 School of Mathematics and Physics China University of GeosciencesWuhan 430074China

We perform a potential analysis for the holographic Schwinger effect in spinning Myers-Perry black *** compute the potential between the produced pair by evaluating the classical action of a string attached on a probe D3-brane at an intermediate position in the AdS *** find that increasing the angular momentum reduces the potential barrier,thus enhancing the Schwinger effect,consistent with previous findings obtained via the local Lorentz *** particular,these effects are more visible for the particle pair lying in the transversal plane compared with that along the longitudinal *** addition,we discuss how the Schwinger effect changes with the shear viscosity to entropy density ratio at strong coupling under the influence of angular momentum.

关键词： AdS/CFT gauge/gravity duality holographic Schwinger effect