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MICROSTRUCTURE EVOLUTION AND MECHANICAL HARDENING OF HYPEREUTECTOID PEARLITIC STEEL DURING COLD ROLLING

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Acta Metallurgica Sinica(English Letters) 2007年第4期20卷 287-292页

作者： x. Zhang C.x. wang x.M. Liu Q.N. Shi Key Laboratory of Advanced Materials of Yunnan Province Kunming University of Science and Technology Kunming 650093 China Institute for Structural Materials Central Iron and Steel Research InstituteBeijing 100081 China

The microstructure evolution of different cold rolling reductions （from 0 to 81.6%） was studied by SEM （scanning electron microscopy） and TEM （transmission electron microscope）. The study showed that the orientation multiplicity of pearlitic lamellas resulted in inhomogeneous deformation of different pearlitic lamellas, and with the increase of reduction, the microstructure underwent a course of ＂homogeneity → inhomogeneity → homogeneity＂. The result of xRD （x-ray diffraction） analysis indicated that cementite did not decompose and dissolve into ferrite; the results of the mechanical property test suggested that the relationship between Rp0.2 （yield strength） and ε （true strain） was in good agreement with Hollomon relationship. With the equation Rp0.2 = 1465ε^0.18, the yield strength of the steel in different reductions could be well predicted.

关键词： cold rolling hypereutectoid pearlitic steel microstructure evolution mechanical hardening

Review of precipitation strengthening in ultrahigh-strength martensitic steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 256-269页

作者： Zhihao Tian Chunlei Shang Chaolei Zhang xiaoye Zhou Honghui Wu Shuize wang Guilin Wu Junheng Gao Jiaming Zhu xinping Mao Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China Institute of Steel Sustainable Technology Liaoning Academy of MaterialsShenyang 110004China Department of Materials Science and Engineering Shenzhen MSU-BIT UniversityShenzhen 518172China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China School of Civil Engineering Shandong UniversityJinan 250061China

Martensite is an important microstructure in ultrahigh-strength steels,and enhancing the strength of martensitic steels often involves the introduction of precipitated phases within the martensitic *** considerable research efforts devoted to this area,a systematic summary of these advancements is *** review focuses on the precipitates prevalent in ultrahigh-strength martensitic steel,primarily carbides(e.g.,MC,M_(2)C,and M_(3)C)and intermetallic compounds(e.g.,Ni Al,Ni_(3)x,and Fe_(2)Mo).The precipitation-strengthening effect of these precipitates on ultrahigh-strength martensitic steel is discussed from the aspects of heat treatment processes,microstructure of precipitate-strengthened martensite matrix,and mechanical ***,a perspective on the development of precipitation-strengthened martensitic steel is presented to contribute to the advancement of ultrahigh-strength martensitic *** review highlights significant findings,ongoing challenges,and opportunities in the development of ultrahigh-strength martensitic steel.

关键词： ultrahigh-strength martensitic steel precipitation strengthening mechanical property carbide intermetallic compound

The antibacterial activity of selected plants towards resistant bacteria isolated from clinical specimens

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Asian Pacific Journal of Tropical Biomedicine 2016年第1期6卷 16-19页

作者： Pratiwi Wikaningtyas elin Yulinah Sukandar Pharmacology and Clinical Pharmacy Research Group School of Pharmacy Bandung Institute of Technology

Objective:To evaluate the antibacterial activity of eight plants against methicillinresistant Staphylococcus aureus(MRSA),extended spectrum beta-lactamase and carbapenemase-resistant Enterobacteriaceae,which are the most prevalent causes of infections in ***:The antibacterial activity was calculated based on the minimum inhibitory concentration using Mueller-Hinton broth in a microdilution ***:The best antibacterial activity,calculated as minimum inhibitory concentration values,against MRSA was shown by the Kaempferia pandurata(Roxb)(***)extract(256 μg/mL) and the Senna alata(***) extract(512 μg/mL).Phytochemical screening of dried *** leaf and its extract showed the presence of flavonoids,alkaloids,saponins,quinones,tannins and sterols,while dried *** and its extract only showed the presence of flavonoids and sterols/***:*** and *** have the potential to be developed as antibacterial agents,especially against MRSA strain,but further in vivo research and discovery of the mode of its action are still needed to shed light on the effects.

关键词： Medicinal plants Antibacterial activity Minimum inhibitory concentration Resistance bacteria Secondary metabolites

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei xue Tong Shi Chenhui Han Heng Zhang Fenrong Liu Haorun Li Yan wang xiaojun Gu Shanghong Zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Oxygen vacancy Hydrocarbon production Reaction mechanism

Nondestructive Evaluation of Ferroelectric Multilayer Capacitors Using Electromechanical Resonances

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Journal of Materials Science & Technology 1995年第2期11卷 114-118页

作者： SUN, HT wang, HF ZHANG, LY YAO, x xi'an Jiaotong Univ Xi'an China

Under the mechanically free and clamped boundary conditions, electromechanical resonances-of ceramic multilayer capacitors are calculated using vibration and piezoelectric equations. Multilayer capacitors made of ferroelectric BaTiO3 and Pb(Mp(1/3)Nb(2/3))O-3 ceramics have been used to examine the theoretical calculation. Frequency spectra of impedance and phase angle, capacitance and loss tangent of the capacitors under de bias fields are carefully measured. A sudden change around the resonant frequency is observed in these spectra. A damped resonance indicates a defective capacitor while an undamped resonance is corresponding to defect free. Experimental results suggest that it is possible to use the spectra as a real time nondestructive evaluation method.

关键词： Capacitors

Synergistic promotion strategy of “dual-site” and “dual-path” to enhance the C–C coupling between CO2 and HCHO driven by photoelectrocatalysis

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Journal of Energy Chemistry 2025年第1期100卷 39-49页

作者： Hongqiang Yang Jianfeng Zheng Guoyu wang Yifei Gao Yatao Yang Jia Li xiaojin Han Yan Cui Zhanggen Huang National Key Laboratory of High Efficiency and Low Carbon Utilization of Coal Institute of Coal Chemistry Chinese Academy of Science University of Chinese Academy of Science Shenyang University of Chemical Technology

Photoelectrocatalytic coupling CO2and volatile organic compounds （VOCs） is a promising green strategy for the synergistic conversion of the two carbon-containing resources to *** catalytic efficiency is always at the mercy of chemical inertness of CO2and the competitive hydrogen evolution of ***,a modified g-C3N4/ZnAl-LDH Z-scheme heterojunction catalyst with dual reaction site was rationally designed and precisely *** Faraday efficiency of ethanol reached 68.67%with a corresponding formation rate of 227.3μmol *** revealed by in-situ characterizations and density functional theory calculations,CO2and HCHO were absorbed at Zn site and N site,***,*CO generated from CO2and HCHO was converted to*CH3O and*CHO on the dual-active-site *** detailed reaction mechanism experiments indicated that C–C coupling only occurred between*CO and*CH3O in electrocatalysis *** from the“*CO+*CH3O”path,another“*CO+*CHO”coupling path was also detected in photoelectrocatalytic *** selectivity of ethanol was significantly enhanced due to the synthesis of dual-site catalyst and the dual-path coupling path between CO2and HCHO simultaneously driven by light and electricity.

关键词： Photoelectrocatalysis Z-scheme C–C coupling Ethanol

Fracture of Aramid Fiber/Epoxy Resin Micro Composites

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Journal of Materials Science & Technology 1995年第4期11卷 260-264页

作者： wang, x ZHANG, Cx JIN, SJ YU, YZ Inst of Chemistry Chinese Acad of Sciences Beijing China

Kevlar-49 fiber was modified through cold air plasma treatment and plasma grafting with acrylic monomers. Fracture of aramid fiber/epoxy resin micro composites has been studied by means of single fiber pull-out test. Tow types of pull-out curves are correlated with the different failure modes. A polyacrylic acid-co-ethyl acrylate graft layer can improve the adhesion and protect the fiber from damage caused by interfacial stresses.

关键词： Fiber reinforced plastics

Enhanced pitting corrosion resistance of a Zr-based metallic glass by ultraviolet light irradiation

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Journal of Iron and Steel Research International 2023年第8期30卷 1642-1649页

作者： Z.Chen D.P.wang S.wang Y.x.Geng Y.x.Guo Y.C.Wu Z.G.Liu Y.Y.Zhang Y.x.wang School of Materials Science and Engineering Jiangsu University of Science and Technology.Zhenjiang 212003JiangsuChina School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina

The influence of ultraviolet light irradiation on the pitting corrosion performance of a Zr_(2)Ni metallic glass was examined using electrochemical methods and immersion test in 0.05 mol/L NaCl *** the results of potentiostatic polarization,the pitting potential of the ultraviolet light-irradiated sample shifted positively with a value of~300 mV,revealing the enhanced pitting corrosion resistance of the *** corrosion morphology after the immersion test also demonstrated lower degree of corrosion damage and improved pitting resistance of the sample with ultraviolet light irradiation.x-ray photoelectron spectroscopy analysis revealed more zirconium enrichment in the passive film and no chloride ions adsorption for the samples with ultraviolet irradiation,accounting for the suppression of the pit generation and *** findings indicate that ultraviolet light irradiation improves the pitting corrosion resistance of the Zr-based metallic glasses,which are promising structural materials to be used in corrosion environments with high ultraviolet irradiation.

关键词： Metallic glass Pitting-Corrosion Ultraviolet light irradiation Passive film

Nanoindentation of soft solids by a fla punch

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Acta Mechanica Sinica 2015年第4期31卷 531-535页

作者： G.F.wang x.R.Niu Department of Engineering Mechanics SVL Xi’an Jiaotong University Department of Mechanical and Biomedical Engineering City University of Hong Kong

Measuring the surface tension and elastic mod- ulus of soft materials and biological tissues under different physiological and pathological conditions is of significance for understanding various phenomena associated with defor- mation. In this paper, the nanoindentation of a circular fiat punch on a soft solid is analyzed with the influence of surface tension. By solving the corresponding singular integral equa- tion, the relation between load and indent depth is obtained. When the radius of the flat punch shrinks to the same order as the ratio of surface tension to elastic modulus, surface ten- sion significantly affects the indentation load-depth relation, which provides a facile method to measure surface tension in soft solids and biological tissues.

关键词： Nanoindentation Surface tension Soft solid Biological tissue