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Corrosion and chemical behavior of Mg_(97)Zn_(1)Y_(2)-1wt.%SiC under different corrosion solutions

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China Foundry 2021年第1期18卷 68-74页

作者： Di-qing Wan Yan-dan Xue Jia-jun Hu hou-bin wang Wei Liu School of Materials Science and Engineering East China Jiaotong UniversityNanchang330013China

To explore the corrosion properties of magnesium alloys, the chemical behavior of a high strength Mg_(97)Zn_(1)Y_(2)-1 wt.%Si C alloy in different corrosion environments was studied. Three solutions of 0.2 mol·L^(-1) NaCl, Na_(2)SO_(4) and NaNO_(3) were selected as corrosion solutions. The microstructures, corrosion rate, corrosion potential, and mechanism were investigated qualitatively and quantitatively by optical microscopy(OM), scanning electron microscopy(SEM), immersion testing experiment, and electrochemical test. Microstructure observation shows that the Mg_(97) Zn_(1)Y_(2)-1 wt.%Si C alloy is composed of α-Mg matrix, LPSO(Mg_(12) ZnY) phase and Si C phase. The hydrogen evolution and electrochemical test results reflect that the Mg_(97)Zn_(1)Y_(2)-1 wt.%SiC in 0.2 mol·L^(-1) Na Cl solution has the fastest corrosion rate, followed by Na_(2)SO_(4) and NaNO_(3) solutions, and that the charge-transfer resistance presents the contrary trend and decreases in turn.

关键词： Mg_(97)Zn_(1)Y_(2)-1wt.%Si C corrosion rate corrosion morphology corrosion mechanism

Effects of Pb on microstructure, mechanical properties and corrosion resistance of as-cast Mg97Zn1Y2 alloys

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China Foundry 2018年第6期15卷 443-448页

作者： Di-qing Wan Ying-lin Hu Shu-ting Ye hou-bin wang Shao-min Wei School of Material Science and Engineering East China Jiaotong University

In this present work, Pb was applied in the Mg97Zn1Y2 alloy to improve its microstructure and properties, using conventional casting methods. The microstructure and properties of the Mg97 Zn1 Y2 alloy and Mg97Zn1Y2-x Pb(x=0.6 wt.%, 1.2 wt.% and 1.8 wt.%) alloys were observed by optical microscopy, scanning electron microscopy method and analyzed by X-ray diffraction, hardness and strength measurement and electrochemical testing. After adding Pb to the Mg97Zn1Y2 alloy, a new particle phase Mg_2 Pb was identified along the grain boundaries, and dendrites were refined. In addtion, the hardness of Mg97Zn1Y2-xPb(x=0.6 wt.%, 1.2 wt.% and 1.8 wt.%) alloys was higher than that of the Mg97 Zn1Y2 alloy; with the increase of Pb content, the hardness of the alloy increased first and then decreased, followed by a final slight increase, and reached a maximum of 89.1 HV when the Pb content was 0.6 wt.%. The strength of the alloy increased first and then decreased as the Pb content increased. Moreover, adding a small amount of Pb to the alloy can effectively inhibit corrosion, and Mg97Zn1Y2-0.6 wt.%Pb exhibits the best corrosion resistance ability.

关键词： Mg-Zn-Y-Pb alloy microstructure LPSO phase mechanical properties corrosion resistance

Aging kinetics of 14H-LPSO precipitates in Mg-Zn-Y alloy

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China Foundry 2020年第1期17卷 42-47页

作者： Di-qing Wan hou-bin wang Zhu-min Li Ying-lin Hu Jia-jun Hu Yan-dan Xue Lin-sen wang Kang-jin Fang School of Materials Science and Engineering East China Jiaotong University

Alloys with long-period stacking ordered structures(LPSO)have good properties and are highly ***-Zn-Y alloy containing LPSO phase was prepared by the traditional casting method,and the aging heat treatment was performed at different temperatures and *** microstructure and phase constitutions of the alloy were observed by means of optical microscopy and scanning electron microscopy *** show the microstructure of as-cast Mg95.5Zn1.5Y3 mainly consists ofα-Mg,W phases and LPSO *** the aging treatment,fine lamellar-shaped 14H-LPSO phase is formed at the grain boundaries and precipitates from the supersaturated magnesium matrix,and the volume fraction increases as the aging time *** controlling the aging time,Mg-Zn-Y alloys with different volume fractions of 14H-LPSO phase were *** aging kinetics equation of the 14H-LPSO phase is summarized,that is f=1-exp(-0.2705 t 0.6368).The phase transformation mechanism of 14H-LPSO in Mg95.5Zn1.5Y3 alloy can be described as the change of dislocation energy.

关键词： magnesium alloy LPSO phase aging kinetics equation

Fe3+ ion quantification with reusable bioinspired nanopores

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Chinese Chemical Letters 2025年第2期36卷 207-212页

作者： Yanqiong wang Yaqi hou Fengwei Huo Xu hou Institute of Flexible Electronics (IFE Future Technologies) Xiang’an Campus Xiamen University State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Institute of Artificial Intelligence Xiamen University Department of Physics Research Institute for Biomimetics and Soft Matter Fujian Provincial Key Laboratory for Soft Materials Research Jiujiang Research Institute College of Physical Science and Technology Xiamen University Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM) Engineering Research Center of Electrochemical Technologies of Ministry of Education Xiamen University

Excessive Fe3+ion concentrations in wastewater pose a long-standing threat to human *** low-cost,high-efficiency quantification of Fe3+ion concentration in unknown solutions can guide environmental management decisions and optimize water treatment *** this study,by leveraging the rapid,real-time detection capabilities of nanopores and the specific chemical binding affinity of tannic acid to Fe3+,a linear relationship between the ion current and Fe3+ion concentration was *** this linear relationship,quantification of Fe3+ion concentration in unknown solutions was ***,ethylenediaminetetraacetic acid disodium salt was employed to displace Fe3+from the nanopores,allowing them to be restored to their initial conditions and reused for Fe3+ion *** reusable bioinspired nanopores remain functional over 330 days of *** recycling capability and the long-term stability of the nanopores contribute to a significant reduction in *** study provides a strategy for the quantification of unknown Fe3+concentration using nanopores,with potential applications in environmental assessment,health monitoring,and so forth.

关键词： Bioinspired nanopores Chemical binding affinity Fe3+ ion quantification Reusability Tannic acid

Experiments and modeling of microstructural and mechanical behaviors of laser-welded Ni-based superalloy at high temperatures

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Chinese Journal of Aeronautics 2025年第1期38卷 99-114页

作者： Ting hou Yong LI Degang wang Yuelin wang Marko VILOTIC School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Department of Structure Shenyang Aircraft Designand Research InstituteShenyang 110000China Engineering Center Shenyang Aircraft CorporationShenyang 110000China Faculty of Technical Science University of Novi SadNovi Sad 21102Serbia

The performance of welded Ni-based superalloys at high temperatures is essential to be evaluated due to their particular service environment for aero-engines and high-speed *** tensile properties and related microstructural evolutions such as the carbide precipitate and grain of a laser-welded Ni-based alloy were experimentally and numerically investigated at different temperatures(20,300,500,800℃).The results show that at room temperature,the strength of the Base Material(BM)was slightly smaller,with a difference of less than 1%,than the Welded Material(WM),which can be attributed to the more uniformly distributed needle-shaped carbide precipitates in the WM than those nonuniformly coarser spherical ones in the *** at 300℃ and 500℃,the strength of WM decreased more obviously compared with that of BM due to the more apparent growth of grain:13.52%loss in yield strength in WM alloys as compared with BM alloys at 300℃,and 16.57% at 500℃.At 800℃,the strength of BM and WM both decreased to a similar level due to Dynamic Recrystallization(DRX).However,a much higher elongation was observed for the BM than WM(less than 50%of BM),which can be attributed to the enhanced dislocation accumulation capability of the large spherical carbides along grain boundaries on the fracture surface in ***,a unified model considering the welding effects on both microstructures(dislocation,carbides,and grain)and mechanical properties evolutions at different temperatures was developed and *** on this model,the key temperature ranges(20–600℃)where apparent weakening of strength and uniform plasticity occurs for welded structures were identified,providing a direct guidance for potential structure and process design.

关键词： Ni-based superalloy Microstructure Mechanical properties Constitutive model High temperature

Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 360-368页

作者： Yumeng wang Qinyi Guo bin Hu Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.

关键词： medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability

Controlled cationic ring-opening polymerization of L-lactide by organic ion pair:novel approach to isotactic-rich and crystalline polylactide

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Science China Chemistry 2025年第1期68卷 394-402页

作者： Zhiqiang Ding Mingqian wang Zijing Zhou bin wang Yuesheng Li Tianjin Key Laboratory of Composite&Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China

Living/controlled cationic ring-opening polymerization(ROP)of L-lactide is a promising approach to isotactic-rich and crystalline poly(L-lactide).In contrast with the unsubstituted lactones,L-LA can not be polymerized by organic Lewis acids or carbenium ions,and the state of the art in this field is the cationic ROP of L-LA catalyzed by BrФnsted acid/alcohol system via activated monomer ***,we reported the first example of controlled cationic ROP of L-LA by using Meerweintype ion pair[Me_(3)O]^(+)[B(C_(6)F_(5))_(4)]^(-)as the catalyst.[Me_(3)O]^(+)[B(C_(6)F_(5))_(4)]^(-)promoted rapid L-LA cationic polymerization in the absence of alcohol,producing isotactic-rich and crystalline PLLA without transesterification and epimerization side *** activated chain end mechanism,involving twice S_(N)2 substitution and configuration-inversion(S→R→S)with the assistance of released Me_(2)O,was proposed and further verified by density functional theory and control *** work expands the catalytic toolbox of isotactic-rich and crystalline polylactide *** represents a unique example of cationic-controlled polymerization of L-LA catalyzed by an organic ion pair.

关键词： organic ion pair controlled cationic ring-opening polymerization activated chain end mechanism isotactic-rich poly-lactide

Strategies for efficient enrichment of anaerobic ammonia oxidizing bacteria in activated sludge

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Journal of Environmental Sciences 2025年第5期151卷 703-713页

作者： bin Tang Jin wang Xingdong Gao Zhihua Li Key Laboratory of Northwest Water Resource Environmentand EcologyMOESchool of Environmental and Municipal EngineeringXi’an University of Architecture and TechnologyXi’an 710055China Xi’an Key Laboratory of Intelligent Equipment Technology for Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Anaerobic ammonia oxidation(Anammox)is an economical and sustainablewastewater nitrogen removal technology,and its application in the mainstream process is the inevitable trend of the development of ***,how to effectively enriching Anammox bacteria from the activated sludge remains challenging and restricts its extensive *** this study,the rapid and efficient enrichment of Anammox bacteriawas achieved by raising the reflux ratio and nitrogen loading rate(NLR)using conventional activated sludge as the *** the screening phase(days 1–90),the reflux ratio was increased to discharge partial floc sludge,resulting in the relative abundance of Candidatus Brocadiaceae increased from0.04%to 22.54%,which effectively reduced thematrix and spatial competition between other microorganisms and Anammox *** day 90,the stoichiometric ratio of the Anammox process closely approached the theoretical value of 1:1.32:0.26,indicating that the Anammox reaction was the primary nitrogen removal process in the *** the enrichment phase(days 91–238),the NLR increased from 0.43 to 1.20 kgN/(m^(3)·d)and removal efficiency was 71.89%,resulting in the relative abundance of Candidatus Brocadiaceae increased to 61.27%on day *** reactor operated steadily from days 444 to 498,maintaining the nitrogen removal rate(NRR)of 3.00 kgN/(m^(3)·d)and achieving successful sludge granulation with the particle size of 392.4μ*** short,this study provided a simple and efficient approach for enriching Anammox bacteria from the activated sludge,supporting to start an Anammox process efficiently.

关键词： Anammox Activated sludge Enrichment Nitrogen removal Strategy

High-resolution Geochemistry in the Lucaogou Formation,Junggar Basin:An Assessment of Heterogeneous Shale Resources

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Acta Geologica Sinica(English Edition) 2025年第1期99卷 177-193页

作者： SUN Shijie ZHANG bin wang Xiaomei TIAN Hua ZHANG Shuichang hou Guiting School of Earth and Space Sciences Peking UniversityBeijing 100871China Research Institute of Petroleum Exploration and Development PetroChinaBeijing 100083China

Controlled by fluctuating paleoclimates and sedimentary environments,the organic and inorganic features of the Lucaogou Formation exhibit strong heterogeneity in the vertical profile,challenging conventional geological *** elucidate the possible influence of heterogeneity on resource evaluation,a high-resolution sampling approach was applied to an 86.2 cm long core from the Lucaogou Formation of the Jimsar sag in the Junggar Basin.86 sets of samples were micro-drilled from the core and subjected to comparative Rock-Eval *** the classical guidelines,the organic abundance,kerogen type,and maturity of source rocks were exhaustively *** results revealed that organic richness and composition vary significantly under different sedimentary backgrounds,which in turn leads to differential hydrocarbon *** combination of hydrocarbon generation,transport,and expulsion results in peculiar patterns for hydrocarbon accumulation in the Lucaogou *** shales in the Lucaogou Formation serve as both hydrocarbon source rocks and reservoirs,with laminae being migration ***-rich dolomites in the Lucaogou Formation have a considerable hydrocarbon-generating capacity and present the characteristics of self-generation and ***,massive mudstones act purely as hydrocarbon source rocks.

关键词： unconventional resource heterogeneity Rock-Eval pyrolysis Lucaogou Formation Junggar Basin