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Rare Metals 2021年第3期40卷 626-634页

作者： Guo-Wei Bo Guan wang Fu-Lin jiang Can Liu rong Chen Hui Zhang College of Materials Science and Engineering Hunan UniversityChangsha410082China School of Mechanical Engineering Ningxia UniversityYinchuan 750021China

An Al-Cu-Mg-Zr alloy,which obtained different homogenization cooling rates by changing the heattreated sample size,was compressed to various strains at the deformation temperature of 300℃ and strain rate of 0.01 s^(-1).The results showed that the homogenization cooling rate had strong effects on the hot deformation behavior of the *** flow stress and relative dynamic softening rate of the alloy were significantly higher under a high cooling rate(HCR) than those under a low cooling rate(LCR).Furthermore,based on X-ray diffraction,scanning electron microscopy,transmission electron microscopy,and thermodynamic equilibrium phase calculation,the substructure evolution in the grain interior,morphology,and spatial distribution of the precipitates were studied to determine the differences in the flow softening *** main softening mechanism could be summarized as dynamic recovery and precipitation coarsening for the LCR alloy and dynamic precipitation for the HCR alloy.

关键词： Al-Cu-Mg-Zr alloy Homogenization Hot compression Flow softening Dynamic precipitation

Fracture Toughnesses and Crack Growth Angles of Single-Layer Graphyne Sheets

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Acta Mechanica Solida Sinica 2019年第3期32卷 339-355页

作者： Zonghuiyi jiang rong Lin Junhua Zhao jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology Jiangnan University Wuxi 214122 China Institute of Mechanics and Advanced Materials School of Mechanical Engineering Jiangnan University Wuxi 214122 China

Recently, Shang et al.(Angew Chem Int Ed 57(3):774-778,2018) have developed a method to synthesize ultrathin (around 1.9 nm) graphyne nanosheets. We reported here the mixed-mode I-II fracture toughnesses and crack growth angles of single-layer graphyne sheets using molecular dynamics (MD) simulations and the finite element (FE) method based on the boundary layer model, respectively. The various carbon-carbon bonds of graphyne sheets in the FE method are equated with the nonlinear Timoshenko beams based on the Tersoff-Brenner potential, where all the parameters of the nonlinear beams are completely determined based on the continuum modeling. All the results from the present FE method are reasonable in comparison with those from our MD simulations using the REBO potential. The present results show that both the critical stress intensity factors (SIFs) and the crack growth angle strongly depend on the chirality and loading angle q @= 90° and #= 0° representing pure mode I and pure mode II, respectively). Meanwhile, the fracture properties of single-layer cyclicgraphene and supergraphene sheets are also studied in order to compare with those of the graphyne sheets. The critical equivalent SIFs are derived as 1.55 < *** (cyclic)< 1.95 nN A-3/2, 1.64 < *** (graphyne)< 2.64 nN A_3/<2 and 0.61 < Keq-su (super)< 2.04 nN A-3/2 in the corresponding zigzag and armchair sheets using the MD simulations, while the SIFs are 0.32 < Keq-cy (cyclic)< 0.48 nN A-3/,2, 1.96 < *** (graphyne)< 2.49 nN A-3^2 and 1.42 < Keq-su (super)< 2.95 nN A_3//2 using the FE method. These findings should be of great help for understanding the fracture properties of carbon allotropes and designing the carbon-based nanodevices.

关键词： Fracture toughness Graphyne Molecular dynamics Finite element

Evaluation of increasing service life of epoxy zinc-rich coating on 3 wt.%Ni-advanced low-alloy steel in marine atmospheric environment

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Journal of Iron and Steel Research International 2022年第4期29卷 698-706页

作者： Sheng-rong wang Jian-wei Yang Jian-ping Cao Shan jiang Fei-fan Xu Shougang Research Institute of Technology of Shougang Group Co. Ltd.Beijing 100043China Beijing Key Laboratory of Green Recyclable Process for Iron&Steel Production Technology Beijing 100043China

The addition of Ni element into steel to prolong the service life of coated steel was investigated in marine atmospheric environment by laboratory simulated accelerated *** scanning electron microscope and electron probe microanalysis combined with electrochemical impedance spectroscopy were used to characterize coated steel properties and examined the anti-corrosion *** results showed that 3 wt.%Ni-advanced steel(3Ni steel)substrate obviously delayed the failure time of coating compared to carbon steel,therefore prolonging the service life of coating on the steel.X-ray diffraction patterns for the corrosion products under the scratched coating on 3Ni steel exhibited that FeNi_(2)O_(4) and Fe_(2)O_(3) occurred in the corrosion product of 3Ni *** was also found that Ni element enriched in the product layer through analyzing the appearance and composition of corrosion products by electron probe *** ions were blocked out of product by the enrichment of Ni element in rust layer.

关键词： 3wt.% Ni-advanced low-alloy steel Coating failure Service life Corrosion product Marine atmosphere

Effect of irradiation on temperature performance of dispersioncompensation no-core cascade optical-fiber sensor coated with polydimethylsiloxane film

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Nuclear Science and Techniques 2022年第9期33卷 10-20页

作者： Fang wang Qiu-Feng Wu Yu-rong jiang Chan Jin Xiao-Hui wang Ben-Shang Zhang Chun-wang Ma College of Electronic and Electrical Engineering Henan Normal UniversityXinxiang 453007China Key Laboratory of Optoelectronic Sensing Integrated Application of Henan Province Xinxiang 453007China School of Physics Henan Normal UniversityXinxiang 453007China Engineering Laboratory of Intelligent Additive Manufacturing of Henan Province Xinxiang 453007China Key Laboratory of Interfacial Physics Technology Project Chinese Academy of SciencesShanghai 201800China Institute of Isotope Research Henan Academy of SciencesZhengzhou 450000China

A temperature measurement device can produce data deviations and can even be damaged in a high-dose radiation *** reduce the radiation damage to such a device and improve the temperature measurement accuracy in a radiation environment,a temperature sensor based on optical-fiber sensing technology is *** sensor has a cascade structure composed of a single-mode fiber(SMF),a dispersion-compensation fiber(DCF),a nocore fiber(NCF),and another SMF(SDNS).The DCF and NCF are coated with a polydimethylsiloxane(PDMS)film,which is a heat-sensitive material with high thermal optical and thermal expansion *** experiments,PDMS was found to produce an irradiation crosslinking effect after irradiation,which improved the temperature sensitivity of the SDNS *** experimental results showed that within a range of 30–100℃,the maximum temperature sensitivity after irradiation was 62.86 pm/℃,and the maximum transmission sensitivity after irradiation was 3.353×10^(-2)dB/℃,which were 1.22 times and 2.267 times the values before irradiation,*** addition,repeated temperature experiments verified that the SDNS sensor coated with the PDMS film had excellent temperature ***,it was found that with an increase in the irradiation intensity,the irradiation crosslinking degree of PDMS increased,and the temperature sensitivity of the sensor was *** proposed sensor could potentially be applied to temperature measurement in a nuclear-radiation environment.

关键词： ^(60)Co-γirradiation Optical-fiber sensor Temperature performance PDMS Radiation crosslinking

ATTRACTORS FOR DISCRETIZATION OF GINZBURG-LANDAU-BBM EQUATIONS

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Journal of Computational Mathematics 2001年第2期19卷 195-204页

作者： Mu-rong jiang Bo-ling Guo Department of Mathematics Yunnan UniversityKunming 650091China R&D Center for Parallel Software Institute of SoftwareChinese Academy of SciencesBeijing 100080China Institute of Applied Physics and Computational Mathematics Beijing 100088China

Focuses on a study which discreted Ginzburg-Landau-BBM equations with periodic initial boundary value conditions by the finite difference method in spatial direction. Background on the discretization of the equations and the priori estimates; Existence of the attractors for the discrete system; Estimates of the upper bounds of Hausdorff and fractal dimensions for the attractors.

关键词： attractor spatially discreted Ginzburg-Landau-BBM equations Hausdorff and fractal dimensions

Epidemic spreading in scale-free networks including the effect of individual vigilance

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Chinese Physics B 2012年第1期21卷 41-45页

作者： Gong Yong-wang Song Yu-rong jiang Guo-Ping College of Computer Nanjing University of Posts and TelecommunicationsNanjing 210003 China School of Information Engineering Yancheng Institute of TechnologyYancheng 224051China College of Automation Nanjing University of Posts and TelecommunicationsNanjing 210003 China

In this paper, we study the epidemic spreading in scale-flee networks and propose a new susceptible-infected- recovered （SIR） model that includes the effect of individual vigilance. In our model, the effective spreading rate is dynamically adjusted with the time evolution at the vigilance period. Using the mean-field theory, an analytical result is derived. It shows that individual vigilance has no effect on the epidemic threshold. The numerical simulations agree well with the analytical result. Purthermore, we investigate the effect of individual vigilance on the epidemic spreading speed. It is shown that individual vigilance can slow the epidemic spreading speed effectively and delay the arrival of peak epidemic infection.

关键词： scale-free network susceptible-infected-recovered model individual vigilance epidemicthreshold

Structural Properties of Ions and Polyelectrolytes in Aqueous Solutions under External Electric Fields:The Sign Effect

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Chinese Journal of Polymer Science 2024年第9期42卷 1341-1352,I0007页

作者： Cheng-jiang Lin Jun-Jun wang Yuan jiang Shu-Li Chen Hong-Fei Li Wen-Han Zhao Qing-rong Huang Chang-Ru rong Xiao-Zheng Duan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China National Key Laboratory of Advanced Vehicle Integration and Control China FAW Group Co.Ltd.Changchun130013China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200438China Department of Food Science Rutgers University65 Dudley RoadNew BrunswickNew Jersey08901USA

We utilize molecular dynamics simulations to investigate the microstructures of ions and polyelectrolytes in aqueous solutions under external electric *** focusing on the multi-body interactions between ionic components and H_(2)O molecules,as well as their responses to the external electric fields,we clarify several nontrivial molecular features of the ionic and polyelectrolyte solutions,such as the solvations of cations and anions,clustering of the ions,and dispersions/aggregations of polyelectrolyte chains,as well as the corresponding responses of H_(2)O molecules in these *** simulations illustrate the variations in structures of ionic solutions caused by reversing the charge sign of the ions,and elucidate the disparity in structures between anionic and cationic polyelectrolyte solutions in the presence of the external electric *** work clarifies the mechanism for the alternations in complex multi-body interactions in aqueous solutions caused by the application electric field,which can contribute to the fundamental understanding of the physical and chemical natures of ion-containing and charged polymeric systems.

关键词： Polyelectrolyte Ions Aqueous solutions External electric fields Asymmetric dipole

PS-HQ:More convenient in situ polymeric cocatalyst for the PdC1_2-catalyzed acetalization in supercritical carbon dioxide

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Chinese Chemical Letters 2007年第8期18卷 969-972页

作者： Zhao Yang wang Huan Feng jiang Chao rong Qi Yan Xia Shen Shao rong Yang College of Chemistry South China University of Technology Guangzhou 510640 China Department of Chemistry South China Normal University Guangzhou 510006 China

Polystyrene-supported hydroquinone （PS-HQ） is presented as an in situ polymeric cocatalyst to replace polystyrenesupported benzoquinone （PS-BQ） in the PdCl2-catalyzed acetalization of methyl acrylate with methanol in supercritical carbon dioxide （scCO2） under oxygen atmosphere. Due to deletion of H2O2 oxidation step, PS-HQ is more convenient and relatively inexpensive.

关键词： Palladium chloride Polymeric supported catalyst Hydroquinone Oxidation Wacker reaction Molecular oxygen

‘‘Amano'' lipase DF-catalyzed efficient synthesis of 2,20-arylmethylene dicyclohexane-1,3-dione derivatives in anhydrous media

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Chinese Chemical Letters 2014年第8期25卷 1190-1192页

作者： Ling jiang Bo wang rong-rong Li Sa Shen Hong-Wei Yu Li-Dan Ye Department of Chemical and Biological Engineering Zhejiang University College of Materials and Chemical Engineering Hainan University School of Chemical and Material Engineering Jiangnan University

A simple and efficient method was developed for the synthesis of 2.2＇-arylmethylene dicyclohexane-1,3- dione derivatives via the Knoevenagel-Michael cascade reactions of aromatic aldehydes and 1,3-cyclic diketones catalyzed by ＂Amano＂ lipase DF, which expands the application field of enzyme catalytic promiscuity. This protocol provides several advantages over the traditional chemical synthesis, such as simple work-up procedure, high yields Cup to 94%） and environmental friendliness.

关键词： "Amano" lipase DF Knoevenagel condensation Michael addition Catalytic promiscuity

Phase diagrams of permanent magnet alloys: Binary rare earth alloy systems

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Journal of Rare Earths 2019年第10期37卷 1040-1046页

作者： Kaicheng Yang jiang wang Qingrong Yao Zhao Lu Maohua rong Huaiying Zhou Guanghui Rao School of Materials Science and Engineering & Guangxi Key Laboratory of Information Materials Guilin University of Electronic Technology

Thermodynamic optimization of the binary rare earth alloy(Cee La, Cee Pr, Cee Nd and Lae Nd) systems was performed in this work through the CALPHAD method based on the critical evaluation of all available phase diagram and thermodynamic data reported in the literature. During the thermodynamic modeling, the solution phases including liquid, bcc, fcc and dhcp, were treated as the substitutional solution model. Thermodynamic parameters of the stable phases in the Cee La, Cee Pr, Cee Nd and Lae Nd binary systems are obtained finally and would be used directly to develop the thermodynamic database of the multi-component Nde Fee B-based alloys, which is indispensable for designing alloy compositions and processes of Nde Fee B permanent magnets with highly abundant rare earth metals.

关键词： Permanent magnets Rare earth alloys Phase diagrams CALPHAD