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Microstructure evolution,mechanical properties and creep mechanisms of Mg-12Gd-1MM-0.6Zr(wt%)magnesium alloy

Journal of Rare Earths 2021年第5期39卷 600-608页

作者： Bibo Li Kui Zhang Guoliang Shi Kaikun Wang Yongjun Li Xinggang Li Minglong Ma Jiawei Yuan State Key Laboratory of Nonferrous Metals and Process GRINM Group Co.Ltd.(GRINM)Beijing 100088China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China GRIMAT Engineering Institute Co. Ltd.Beijing 101407China General Research Institute for Nonferrous Metals Beijing 100088China

In this research,the microstructure evolution,mechanical properties,and creep mechanisms of Mg-12 Gd-1 MM-0.6 Zr(wt%)alloy under different conditions were systematically studied using scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),and tensile creep *** the microstructure of the as-cast sample,the average grain size is about 42μm,and the eutectic compounds were determined to be Mg_(5)(Gd_(0.8)MM_(0.2)).During homogenization,these eutectic compounds gradually dissolve,and Mg_(12)MM particles are *** hot extrusion,complete dynamic recrystallization(DRX)occurs,resulting in equiaxial grains with an average grain size of about 12μm and the formation of streamlines consisting of Mg_(12)MM particles along the extrusion direction(ED).After T5 treatment(225℃for 7 h),a large number ofβ'(Mg_(7)Gd)phases are precipitated on the{11-20}αhabit plane and are interconnected,forming an interlaced network *** ultimate tensile strength(R_(m)=405 MPa)and yield strength(R_(P0.2)=288 MPa)of the T5 sample are significantly higher than those of the as-extruded sample(R_(m)=289 MPa,R_(P0.2)=185 MPa),but the elongation(A=4%)was remarkably lower than that of the as-extruded sample(A=18%).When crept at225℃under 100 MPa,the steady-state creep rates of the as-cast,as-extruded,and T5 samples are1.59×10^(-8),1.08×10^(-8),and 1.40×10^(-8)s^(-1),respectively,and their total strains within 100 h are respectively breaking,0.81%,and 0.92%,indicating that the as-extruded alloy exhibits the best creep *** analysis reveals that,during the creep process of the T5 sample,theβ'particles coarsen and the precipitate-free zones(PFZs)widen,which increase the steady-state creep rate and the total strain within 100 h as compared with the as-extruded sample.

关键词： Magnesium alloy Extrusion Creep mechanism Microstructure evolution Precipitation Rare earths

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Remediation of Groundwater Contaminated with Sulfonamides Through In-Situ Activation of Peroxymonosulfate by Supported Hierarchical Cuo/Mgo Nanosheets

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SSRN 2022年

作者： Wang, Gen Liu, Zhuoyue Ge, Lei Wang, Ke Yin, Haochen Pang, Yumeng Yang, Shengjiong Miao, Delu Shaanxi Key Laboratory of Environmental Engineering School of Environmental and Municipal Engineering Xi’an University of Architecture and Technology Shaanxi Xi’an710055 China China Southwest Architectural Design and Research Institute Co. Ltd Sichuan Chengdu610084 China CAS Key Laboratory of Green Process and Engineering State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China

Groundwater contamination by sulfonamides (SAs) has aroused great concern due to their potential risks to ecosystem and public health. In this work, for the first time, simultaneous degradation different SAs was studied via a single oxygen dominated peroxymonosulfate (PMS) activation process. Recoverable hierarchical CuO/MgO nanosheets (NSs), which was in situ grown on monolithic minerals, was synthesized and employed as a PMS activator. Effective degradation of sulfamethoxazole (SMX), sulfamethazine (SMZ), sulfadiazine (SDZ), sulfamerazine (SMR) and sulfathiazole (STZ) was obtained by PMS activated over CuO/MgO NSs. In a fixed-bed column of the supported hierarchical CuO/MgO NSs, simultaneous degradation of different SAs in complicated water matrix was observed with high removal efficiency, long-term stability and strong anti-interference capability toward background constituents of groundwater matrix. Mechanistic studies elucidated that incorporating CuO with defective-rich MgO induced highly oxidative Cu3+. Then PMS was activated by CuO and MgO synergistically via the redox cycle of Cu3+/Cu2+ and oxygen vacancies on MgO. Singlet oxygen (1O2) was proved to be responsible for the degradation of SAs. This study may help to understand the simultaneous degradation of different SAs in a nonradical oxidation process and provide a feasible technology for remediating SAs-contaminated groundwater. © 2022, The Authors. All rights reserved.

关键词： Nanosheets

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Performance Evaluation on Chemical Looping Oxidative Dehydrogenation of Ethane Via Fe2O3@SiO2 Oxygen Carriers

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SSRN 2024年

作者： Wang, Zhichao Liang, Wei Li, Meixin Yang, Xiantan Sun, Zhongshun Yang, Bolun Sun, Bing Wu, Zhiqiang Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and Technology Xi'an Jiaotong University Shaanxi Xi’an710049 China State Key Laboratory of Chemical Safety SINOPEC Research Institute of Safety Engineering Co. Ltd. Qingdao266071 China

Precisely controlling the matching between lattice oxygen migration rates and surface reaction kinetics is a critical challenge in designing oxygen carriers for the partial oxidation of lower alkanes. In this study, the introduction of SiO2 encapsulation enabled the nanostructuring of the oxygen carrier, allowing for the successful tuning of the lattice oxygen reactivity in the Fe2O3 redox oxygen carrier. This, in turn, achieved efficient ethylene production in the chemical looping oxidative dehydrogenation (CL-ODH) of ethane. The incorporation of SiO2 effectively reduced the grain size of the Fe2O3 oxygen carrier, providing more active sites and enabling efficient and well-regulated lattice oxygen migration. As a result, the Fe2O3 oxygen carrier exhibited an optimal match between lattice oxygen migration rates and surface reaction kinetics, achieving a 41.0% ethane conversion and 60.1% ethylene selectivity under the conditions of processing 120 mL of ethane at 700 °C in a single cycle. This work not only provides a highly active CL-ODH oxygen carrier but also offers an effective approach for future large-scale industrial production of chemical looping oxidative dehydrogenation of ethane. © 2024, The Authors. All rights reserved.

关键词： Surface reactions

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Microstructure and corrosion resistance of bone-implanted Mg-Zn-Ca-Sr alloy under different cooling methods

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Rare Metals 2021年第3期40卷 643-650页

作者： He-Ning Liu Kui Zhang Xing-Gang Li Yong-Jun Li Ming-Long Ma Guo-Liang Shi Jia-Wei Yuan Kai-Kun Wang State Key Laboratory of Nonferrous Metals and Process GRINM Group Co.Ltd.Beijing 100088China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China GRIMAT Engineering Institute Co. Ltd.Beijing 101407China General Research Institute for Nonferrous Metals Beijing 100088China

The cooling gradient of Mg-3 Zn-1 Ca-0.5 Sr alloy in cast ingots under different cooling methods(air cooling,warm-water cooling and ice-water-mixture cooling) was examined and the effect of cooling rate on the structure and corrosion properties was *** microstructure of the alloy was composed of α-Mg,Ca_(2) Mg_(6) Zn_(3) and Mg_(17)Sr_(2) *** the solidification cooling rate increased,the grain was refined,Zn and Sr were less segregated,the distributions of Zn and Sr were more uniform,and corrosion rate was found to first increase and then decrease;this contradicts the findings of recent *** cooling rate increasing,the number of corroded microcouples comprising second phase and α-Mg *** α-Mg participates in corrosion,leading to a layered and deep corrosion pit and an increased corrosion ***,as the microstructure became sufficiently dense,the corroded structure protected the deep α-Mg from participating in corrosion,thus reducing the corrosion rate.

关键词： Corrosion Mg-Zn-Ca-Sr Morphology Cooling methods

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Vanadium Pentoxide Nanowires Preparation Via Kinetic Control of Vanadium Oxytrichloride Catalytic Oxidation with Apcvd

SSRN

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SSRN 2024年

作者： Fan, Chuanlin Ye, Lanshan Yue, Fen Chen, Chenchen Zhu, Qingshan Ma, Sugang Pan, Feng Ge, Yu State Key Laboratory of Mesoscience and Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China University of Chinese Academy of Sciences Beijing100049 China China University of Mining and Technology Beijing100083 China

Vanadium pentoxide nanowires were successfully fabricated using vanadium oxytrichloride oxidation with copper oxide nanoparticles serving as catalysts via atmospheric pressure chemical vapor deposition. Kinetic parameters such as temperature and flow velocity were proved to play important roles in the morphologic control of as-deposited product. Vanadium pentoxide nanowires with an average length of ~10 μm and a diameter of 50 - 100 nm, were obtained under the optimum conditions. A root growth mechanism of nanowires was proposed that precursor was readily captured by catalyst nanoparticles at the beginning of deposition, forming nucleation sites. Subsequently, the anisotropic growth of vanadium pentoxide is primarily governed by energy minimization under the reaction rate limited conditions. The presence of oxygen vacancies in the nanowires was confirmed by Raman, XPS and photoluminescence characterization, indicating promising applications in functional materials manufacture. The novel route for preparing vanadium pentoxide nanowires provides an alternative pathway for transitioning traditional vanadium industry towards advanced functional materials development. © 2024, The Authors. All rights reserved.

关键词： Nanowires

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Engineered microbial platform confers resistance against heavy metals via phosphomelanin biosynthesis

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Nature Communications 2025年第1期16卷 1-15页

作者： Ren, Xiaokang Zhao, Luyang Shen, Jintao Zhou, Peng Zhao, Kaili Yuan, Chengqian Xing, Ruirui Yan, Xuehai State Key Laboratory of Biopharmaceutical Preparation and Delivery Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China Center for Mesoscience Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China

Environmental concerns are increasingly fueling interest in engineered living materials derived from microbial sources. Melanin biosynthesis in microbes, particularly facilitated by recombinant tyrosinase expression, offers sustainable protection for the habitat of microorganisms against severe environmental stressors. However, there exists a vast urgency to optimize these engineered microbial platforms, which will amplify their protective capabilities, integrate multifaceted functions, and thereby expand their utility and effectiveness. Here, we genetically engineer microbial platforms capable of endogenously biosynthesizing phosphomelanin, a unique phosphorus-containing melanin. The ability to heterogeneously biosynthesize phosphomelanin endows the microbes with enhanced resistance to heavy metals, thus safeguarding their survival in adverse conditions. Furthermore, we upgrade these engineered microbes by integrating PET-degrading enzymes, thereby achieving effective integrated management of metallized plastic waste. This engineered microbial platform, with its phosphomelanin biosynthetic capabilities, presents significant opportunities for microbes to engage in bioengineering manufacturing, potentially serving as the next-generation guardians against global ecological challenges. © The Author(s) 2025.

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Micro reactors for measurement and analysis of thermochemical gas-solid reactions

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Resources Chemicals and Materials 2022年第2期1卷 152-166页

作者： Zhennan Han Junrong Yue Chao Wang Xi Zeng Jian Yu Fang Wang Yu Guan Xuejing Liu Fu Ding Liangliang Fu Xin Jia Xingfei Song Dingrong Bai Guangwen Xu Key Laboratory on Resources Chemicals and Material of Ministry of Education Shenyang University of Chemical TechnologyShenyang 110142China The State Key Laboratory of Multi-phase Complex System Institute of Process EngineeringChinese Academy of ScienceBeijing 100190China School of Ecology and Environment Beijing Technology and Business UniversityBeijing 100048China

Micro reactors are the essential part of thermal analysis techniques for characterizing gas-solid thermochemical reactions. The dynamic and diversified needs for investigating various complex materials and gas-solid reactions have led to the development of a variety of different microreactors over the years. Solid particles in microreactors are normally heated by furnaces from outside, resistive elements from inside, direct contact with bed particles, or other non-resistively methods. Solid particles can be fixed or fluidized in reactors where gas-solid contacts vary from diffusion-dominated to nearly diffusion-free conditions. Based on these characteristics, in this article we presented a broad classification for microreactors used for thermal analysis of gas-solid reactions. For each of the most popularly used microreactors, their features and limitations are briefly reviewed. By addressing the diversity of the microreactors used in the field of thermal analysis, the review aims at providing general guidance for the selection and operation of the microreactor to satisfy one's practical specific needs.

关键词： Microreactors Thermal analysis Gas-solid reaction Kinetics Mechanism

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Realization of Topology-Controlled Photonic Cavities in a Valley Photonic Crystal

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Physical Review Letters 2025年第3期134卷 033803-033803页

作者： Bei Yan Baoliang Liao Fulong Shi Xiang Xi Yuan Cao Kexin Xiang Yan Meng Linyun Yang Zhenxiao Zhu State Key Laboratory of Optical Fiber and Cable Manufacturing Technology Department of Electronic and Electrical Engineering Guangdong Key Laboratory of Integrated Optoelectronics Intellisense Southern University of Science and Technology Shenzhen 518055 China Hubei Province Key Laboratory of Systems Science in Metallurgical Process and College of Science Wuhan University of Science and Technology Wuhan 430081 China Guangdong Province Key Laboratory of Optical Fiber Sensing and Communications Institute of Photonics Technology Jinan University Guangzhou 510632 China School of Physics & State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen University Guangzhou 510275 China School of Electrical Engineering and Intelligentization Dongguan University of Technology Dongguan 523808 China College of Aerospace Engineering Chongqing University Chongqing 400030 China

We report the experimental realization of a new type of topology-controlled photonic cavities in valley photonic crystals by adopting judiciously oriented mirrors to localize the valley-polarized edge states along their propagation path. By using microwave frequency- and time-domain measurements, we directly observe the strong confinement of electromagnetic energy at the mirror surface due to the extended time delay required for the valley index flipping. Moreover, we experimentally demonstrate that both the degree of energy localization and quality factors of the topology-controlled photonic cavities are determined by the valley-flipping time which is controlled by the topology of the mirror. These results extend and complement the current design paradigm of topological photonic cavities.

关键词： Mirrors

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Boosting methanol electro-oxidation to formate by trace iron induced suppression of cobalt(Ⅳ)formation

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Nano Research 2025年第5期18卷 230-239页

作者： Jialong Lin Xinlin Wang Bingxue Cheng Ruiheng Zhou Yuhang Li Tamao Ishida Guangli Xiu Toru Murayama Mingyue Lin State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process Shanghai Environmental Protection Key Laboratory on Environmental Standard and Risk Management of Chemical PollutantsSchool of Resources and Environmental EngineeringEast China University of Science and TechnologyShanghai 200237China School of Materials Science and Engineering East China University of Science and TechnologyShanghai 200237China Department of Applied Chemistry for Environment Graduate School of Urban Environmental SciencesTokyo Metropolitan UniversityTokyo 192-0397Japan Institute for Catalysis Hokkaido UniversityHokkaido 001-0021Japan Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Converting methanol to high-value formate through electrochemical methods can significantly reduce the energy consumption associated with conventional production *** this study,we directly synthesized iron-doped cobalt phosphate(Fe-CoPO)on nickel foam(NF)to achieve excellent activity for the methanol electro-oxidation reaction(MOR).Our results demonstrated that Fe-CoPO produced a current density of 100 mA·cm^(−2)at a significantly low operating potential of 1.436 V(*** hydrogen electrode(RHE))and operated steadily for 16 h at this current density with a Faradaic efficiency(FE)of 97%.Furthermore,Fe-CoPO maintained a high FE of 100%even at an extremely high current density of 300 mA·cm^(−2)for 8 *** found that the high MOR activity of Fe-CoPO results from electrochemical reconstruction to generate the Co^(2+/3+)-O *** heterogeneous interface between Fe and Co inhibits the formation of Co^(4+),which significantly enhances the MOR ***,this work not only provides insights into the mechanism of MOR over Co-based catalysts but also offers a novel direction for developing highly active MOR catalysts.

关键词： cobalt phosphate methanol electro-oxidation reaction formate Fe doping electrocatalysis

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Fouling Behavior of Nanofiltration Membrane During the Refining Treatment of Morphlines-Dominant Reverse Osmosis Concentrate

SSRN

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SSRN 2024年

作者： Li, Yahui Dong, Yanan Chen, Shangqing Wu, Yingqiu Wang, Junfeng Nie, Yi Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China Innovation Academy for Green Manufacture Chinese Academy of Sciences Beijing100190 China University of Chinese Academy of Sciences Beijing100049 China Petrochemical Research Institute PetroChina Beijing102206 China School of Chemical Engineering and Pharmacy Hubei Key Lab of Novel Reactor & Green Chemical Technology Key Laboratory of Green Chemical Engineering Process Ministry of Education Wuhan Institute of Technology Wuhan430205 China

Nanofiltration (NF) has shown significant promise for separating morpholines with a molecular weight below 200 Da in refining reverse osmosis concentrate (ROC). However, its application is severely hampered by membrane fouling resulting from complex interactions between the membrane and organic/inorganic substances present in ROC. Our prior research identified the DK membrane as highly efficient in separating morpholine from high-saline NaCl-rich aqueous solutions during ROC treatment. Nevertheless, permeability notably decreased over prolonged operation. To ensure the long-term stability of nanofiltration operations, this study delves into the fouling behavior of individual substances present in hydrosaline organic solutions on nanofiltration membranes, aiming to elucidate the fouling mechanism. Consequently, we systematically investigated the effects of salts (NaCl and Na2SO4), organic substances (including N-(2-hydroxypropyl) morpholine (NMH) and 4-morpholineacetate (MHA)), and representative divalent ions (Ca2+ and Mg2+) on the performance and physicochemical properties of the DK membrane. Our findings revealed that both salts and organics induced swelling of the DK membrane, resulting in an enlargement of the mean effective pore size, thereby allowing more organic molecules to permeate the membrane pores. Notably, MHA caused irreversible pore blocking. Additionally, increasing Ca2+ concentrations led to gypsum scaling on the membrane surface, with NMH potentially acting as nuclei, expediting gypsum crystal formation during CaSO4 crystallization. In conclusion, this study systematically elucidated the fouling behavior of substances present in high-saline organic wastewater on DK membranes, proposing corresponding fouling mechanisms. These insights offer valuable guidance for membrane fouling control and cleaning in treating high salinity and organic wastewater. © 2024, The Authors. All rights reserved.

关键词： Nanofiltration

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