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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 750-763页

作者： Jia Liu Shuanglu Duan Xiaokang Yue Ningsong Qu College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The Ti-5Al-2Sn-4Zr-4Mo-2Cr-1Fe(β-CEZ)alloy is considered as a potential structural material in the aviation industry due to its outstanding strength and corrosion resistance.Electrochemical machining(ECM)is an efficient and low-cost technology for manufacturing theβ-CEZ alloy.In ECM,the machining parameter selection and tool design are based on the electrochemical dissolution behavior of the materials.In this study,the electrochemical dissolution behaviors of theβ-CEZ and Ti-6Al-4V(TC4)alloys in NaNO3solution are discussed.The open circuit potential(OCP),Tafel polarization,potentiodynamic polarization,electrochemical impedance spectroscopy(EIS),and current efficiency curves of theβ-CEZ and TC4 alloys are analyzed.The results show that,compared to the TC4 alloy,the passivation film structure is denser and the charge transfer resistance in the dissolution process is greater for theβ-CEZ alloy.Moreover,the dissolved surface morphology of the two titanium-based alloys under different current densities are analyzed.Under low current densities,theβ-CEZ alloy surface comprises dissolution pits and dissolved products,while the TC4 alloy surface comprises a porous honeycomb structure.Under high current densities,the surface waviness of both the alloys improves and the TC4 alloy surface is flatter and smoother than theβ-CEZ alloy surface.Finally,the electrochemical dissolution models ofβ-CEZ and TC4 alloys are proposed.

关键词： electrochemical machining dissolution behavior β-CEZ titanium alloy polarization curve current efficiency

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dissolution behavior of bioactive glass ceramics with different CaO/MgO ratios in SBF-K9 and r-SBF

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Progress in Natural Science:Materials International 2014年第4期24卷 354-363页

作者： M.U.Hashmi Saqlain A.Shah Department of Applied Sciences Superior University Lahore 2. Department of PhysicsFC College (A Chartered University) Department of Material Science and Engineering Washington University

In the present work,we studied dissolution behavior of three glass ceramics samples each having 34 SiO2–14.5 P2O5–1 CaF2–0.5 MgF2(%wt)and ratio of CaO/MgO varying from 11.5:1 to 1:11.5 in conventional SBF(SBF-K9) and revised SBF(r-SBF) that has ionic concentration exactly equal to that of human blood plasma.For that purpose,samples were immersed in fluids for different time periods upto 25 days.Thin film XRD analysis revealed the diffusive nature of the phases on the surfaces of samples after soaking for different time periods in r-SBF.It showed the poor precipitation and small thickness of the HCAp layer on the samples as compared to that in SBF-K9,thus indicating the fitness and sensitivity of r-SBF for in-vitro characterization of samples.AAS,FTIR and EDS revealed slow bonding rate on the surfaces of the samples in r-SBF than that in SBF-K9 that showed the dependence of bond formation on the composition of the materials as well as on the physiological fluid used for in-vitro characterization.The rate of HCAp formation was slower in r-SBF due to more competitive adsorption of CO3 ions to Ca and Mg ions owing to greater amount of CO3 in r-SBF than that in SBF-K9.It shows the importance of CO3 content in the physiological fluids for the in-vitro assessment of samples.So,r-SBF is recommended to be used for assessment of samples to clearly understand their behavior in-vivo.

关键词： dissolution behavior SBF-K9 r-SBF

The accumulation and toxicity of ZIF-8 nanoparticles in Corbicula fluminea

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Journal of Environmental Sciences 2023年第5期127卷 91-101页

作者： Cuilian Yang Jia Wen Zhuangzhuang Xue Xiyan Yin Yangfang Li Li Yuan College of Environmental Science and Engineering Hunan UniversityChangsha 410082China Key Laboratory of Environmental Biology and Pollution Control(Hunan University) Ministry of EducationChangsha 410082China

Metal-organic frameworks(MOFs)are promising new materials that have been intensively studied and possibly applied to various environmental remediation.However,little is known about the fate and risk of MOFs to living organisms in thewater environment.Here,the toxic effects of ZIF-8 nanoparticles(NPs)on benthic organisms were confirmed by sub-chronic toxicity experiments(7 and 14 days)using Corbicula fluminea as the model organism.With exposure doses ranging from 0 to 50 mg/L,ZIF-8 NPs induced oxidative stress behaviors similar to the hormesis effect in the tissues of C.fluminea.The oxidative stress induced by ZIF-8 NPs and the released Zn^(2+)was the crucial cause of the toxic effects.Besides,we also found that the ZIF-8 NPs and dissolved Zn^(2+)may result in different mechanisms of toxicity and accumulation depending on the dosages.The Zn^(2+)release rate of ZIF-8NPswas high at low dosages,leading to a higher proportion of Zn^(2+)taken up by C.fluminea than the particulate ZIF-8.Conversely,at high dosages,C.fluminea mainly ingested the ZIF-8 NPs and resulted in increased mortality.The results have important implications for understanding the fate and biological effects of ZIF-8 in natural aquatic environments.

关键词： ZIF-8 nanoparticles dissolution behavior Benthic organism Ecotoxicity

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dissolution behavior of various elements from steelmaking slag into seawater

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Baosteel Technical Research 2010年第S1期4卷 139-页

作者： Hiroyuki MATSUURA Fumitaka TSUKIHASHI Graduate School of Frontier Sciences The University of Tokyo Chiba 2778561Japan

The mixture of steelmaking slag,soil or sand is a candidate material for the landfill in sea shore to improve the marine environment,because the ferrous ion contained in the steelmaking slag plays an important role in promoting the growth of various seaweeds.However,the dissolution mechanism of various elements from steelmaking slag into seawater is not clarified.To reveal the dissolution behavior of various elements from steelmaking slag into seawater,the dissolution experiment of slag and seawater mixture was conducted at room temperature with changing the basicity of slag and the mass ratio of slag and seawater.It is shown that Mg ion contained in the seawater plays a buffering action obviously on pH increase which is provided by the dissolution of Ca.The dissolution behavior of Si strongly depends on the basicity of slag,at the same time the mass ratio has a conspicuous influence on it for the lower basicity of slag.The dissolution amount of Fe is little and it is discussed by using the solubility diagram.

关键词： steelmaking slag dissolution behavior marine environment

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dissolution kinetics of solid fuels used in COREX gasifier and its influence factors

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Journal of Iron and Steel Research(International) 2018年第3期25卷 298-309页

作者： Run-sheng Xu Jian-liang Zhang Wei Wang Hai-bin Zuo Zheng-liang Xue Ming-ming song State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Wuhan 430081Hubei China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083 China State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China

Carbon dissolution from solid fuels used in a COREX gasifier was investigated in a high-temperature furnace to investigate the influences of temperature, carbon structure and ash properties of solid fuels into molten iron on carbon dissolution behavior. The results showed that the final carbon content of molten iron and dissolution reaction rate of carbon increased as the temperature increased. However, the dissolution behavior of different solid fuels varied with their properties. At the same temperature, the dissolution reaction rate of solid fuel from high to low was coke, semi-coke and lump coal. The apparent reaction rate constants of solid fuel were calculated using the piecewise fitting method based on the experimental data. The analyzed results showed that the dissolution rates of solid fuels had a good correlation with their microcrystalline structures. Moreover, the carbon crystallite structures of solid fuels used in COREX had greater influence on dissolution behavior than their ash properties.

关键词： Solid fuel COREX dissolution behavior Temperature Carbon structure Ash property

Coatings of needle/stripe-like fluoridated hydroxyapatite on H2O2-treated carbon/carbon composites prepared by induction heating and hydrothermal methods

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Frontiers of Materials Science 2012年第2期6卷 160-167页

作者： Xin-Bo XIONG Jian-Feng HUANG Xie-Rong ZENG Ping LIANG I Ji-Zhao ZOU Shenzhen Key Laboratory of Special Functional Materials Department of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China Key Laboratory of Auxiliary Chemical&Technology for Chemical Industry(Ministry of Education) Shaanxi University of Science and TechnologyXi'an 710021China

A hydroxyapatite （HA） coating was achieved on H2O2-treated carbon/ carbon （C/C） composite through hydrothermally treating and induction heating deposited CaHPO4 coating in an ammonia solution under ultrasonic water bath. Then, this HA coating was placed in a NH4F solution and hydrothermally treated again to fabricate fluorinated hydroxyapatite （FHA） coatings for 24 h at 353, 373, 393 and 413 K, respectively. The structure, morphology and chemical composition of the HA and FHA coatings were characterized by SEM, XRD, EDS and FTIR, and the adhesiveness and chemical stability of these FHA coatings were examined by a scratch test and an immersion test, respectively. The results showed that the as-prepared FHA coatings contained needle-like or stripe-like crystals, different from those of the HA coating. As the fluoridation temperature rose, the adhesiveness of the FHA coating first increased from 34.8 to 40.9 N at a temperature between 353 and 393 K, and then decreased to 24.2 N at 413 K, while the dissolution rate of the FHA coating decreased steadily. The reasons for the property variation of the FHA coatings were proposed by analyzing the morphology, composition and structure of the coatings.

关键词： carbon hydroxyapatite （HA） coating scratch test dissolution behavior