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Cs_(3)Bi_(2)l_(9)-hydroxyapatite composite waste forms for cesium and iodine immobilization

Journal of Advanced Ceramics 2022年第5期11卷 712-728页

作者： Kun YANG Yachun WANG Junhua SHEN Spencer M.SCOTT Brian J.RILEY John D.VIENNA Jie LIAN Department of Mechanical Aerospaceand Nuclear EngineeringRensselaer Polytechnic InstituteTroyUSA Department of Materials Science&Engineering Rensselaer Polytechnic InstituteTroyUSA Savannah River National Laboratory AikenUSA Pacific Northwest National Laboratory RichlandUSA

Perovskite-based ceramic composites were developed as potential waste form materials for immobilizing cesium(Cs)and iodine(I)with high waste loadings and chemical *** perovskite Cs_(3)Bi_(2)I_(9)has high Cs(22 wt%)and I(58 wt%)content,and thus can be used as a potential host phase to immobilize these critical *** this work,the perovskite Cs_(3)Bi_(2)I_(9)phase was synthesized by a cost effective solution-based approach,and was embedded into a highly durable hydroxyapatite matrix by spark plasma sintering to form dense ceramic composite waste *** chemical durabilities of the monolithic Cs_(3)Bi_(2)I_(9)and Cs_(3)Bi_(2)I_(9)-hydroxyapatite composite pellets were investigated by static and semi-dynamic leaching tests,*** and I are incongruently released from the matrix for both pure Cs_(3)Bi_(2)I_(9)and composite *** normalized Cs release rate is faster than that of I,which can be explained by the difference in the strengths between Cs-I and Bi-I bonds as well as the formation of insoluble micrometer-sized BiOI *** activation energies of elemental releases based on dissolution and diffusion-controlled mechanisms are determined with significantly higher energy barriers for dissolution from the composite versus that of the monolithic Cs_(3)Bi_(2)I_(9).The ceramic-based composite waste forms exhibit excellent chemical durabilities and waste loadings,commensurate with the state-of-the-art glass-bonded perovskite composites for I and Cs immobilization.

关键词： cesium(Cs) iodine(Ⅰ) perovskite nuclear waste hydroxyapatite

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WE43 Surface Composite with Oxide Particles by Friction Stir Processing

WE43 Surface Composite with Oxide Particles by Friction Stir...

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Magnesium Technology Symposium, 2025, held as part of the TMS Annual Meeting and Exhibition, TMS 2025

作者： Ghauri, Hamza Faisal Shunmugasamy, Vasanth C. Mansoor, Bilal Department of Materials Science and Engineering Texas A&M University College StationTX77840 United States Mechanical Engineering Program Texas A&M University at Qatar Doha Qatar Department of Mechanical Engineering Texas A&M University College StationTX77840 United States

ISBN: (纸本)9783031810602

WE43WE43 has superior mechanical and corrosionCorrosion performance compared to other magnesium alloysMagnesium alloy but surface treatments, mechanical processes, and heat treatments to further enhance its properties continue to be explored. Here we present our preliminary findings about a WE43WE43surface compositeSurface composite with oxide particles produced using friction stir processingFriction stir processing. Significant grain refinement, precipitate redistribution, and increase in microhardness by 25% were achieved in processed regions compared to base material. CorrosionCorrosion testing in 0.9% NaCl solution revealed that the FSP-treated material exhibited a 196% lower Icorr and a more stable open circuit potential (OCP) than cast WE43WE43, suggesting superior corrosion resistanceCorrosion resistance. While the findings promise suitability of the processed alloy for a more intensive range of operating conditions than the cast alloy, further work to study the effect of the size, volume, and composition of the oxide reinforcements needs to be carried out. © The Minerals, Metals & materials Society 2025.

关键词： Grain refinement

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Fracture toughness of a rejuvenated β-Ti reinforced bulk metallic glass matrix composite

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Journal of materials science & Technology 2022年第11期106卷 225-235页

作者： Devashish Rajpoot R.Lakshmi Narayan Long Zhang Punit Kumar Haifeng Zhang Parag Tandaiya Upadrasta Ramamurty Department of Mechanical Engineering Indian Institute of Technology BombayPowaiMumbai400076India Department of Mechanical and Aerospace Engineering in Nanyang Technological University Singapore 637331Republic of Singapore Department of Materials Science and Engineering Indian Institute of Technology DelhiHauz KhasNew Delhi110016India Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China Institute of Materials Research and Engineering Agency for ScienceTechnology and Research(A∗STAR)Singapore 138634Republic of Singapore

A β-Ti dendrite reinforced Zr-based bulk metallic glass composite(BMGC) was found to be brittle when cast in a large size. The reasons for the embrittlement and the effectiveness of the cryothermal cycling(CTC) treatment in restoring the mode I fracture toughness are examined. Plasticity in all the CTC treated BMGC is estimated from the distribution and occurrence of pop-ins in nanoindentation tests and by measuring the magnitude of enthalpy of relaxation(△H_(rel)) via differential scanning calorimetry(DSC). This is further validated by examining the strain-to-failure(ε_(f)) in compression tests. Mode I fracture behaviour of the as-cast embrittled BMGC and the CTC treated BMGC, which exhibits maximum plasticity, is examined. Results show that both BMGCs are equally brittle and exhibit 5 times lower notch toughness(K_(QJ))than their tougher counterpart. Post-facto imaging of the side surfaces reveals the absence of notch-tip plasticity in both BMGCs. The lack of notch tip plasticity of CTC treated BMGC, despite exhibiting signatures of plasticity in nanoindentation and higher △Hrelis rationalized by reassessing the origin of pop-ins in nanoindentation tests and describing the variations in chemical and topological short range ordering during CTC, respectively. Implications of these results in terms of improving the fracture toughness of structurally relaxed BMGCs via CTC are discussed.

关键词： Bulk metallic glass composites Fracture Rejuvenation Shear bands Microsegragation

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Bimetallic NiCoP catalysts anchored on phosphorus-doped lignin-based carbon for robust oxygen evolution performance

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Rare Metals 2024年第7期43卷 3084-3095页

作者： Ling-Ying-Zi Xiong Bo-Wen Liu Lei Du Yue-Kuan Zhou Xu-Liang Lin Huan Wang Guangdong Engineering Technology Research Center for Sensing Materials&Devices Guangzhou Key Laboratory of Sensing Materials&DevicesSchool of Chemistry and Chemical EngineeringGuangzhou UniversityGuangzhou 510006China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center Jieyang 515200China Sustainable Energy and Environment Thrust Function HubThe Hong Kong University of Science and Technology(Guangzhou)Guangzhou 511400China Division of Emerging Interdisciplinary Areas Department of Mechanical and Aerospace EngineeringThe Hong Kong University of Science and TechnologyHong Kong 999077China State Key Lab of Pulp and Paper Engineering South China University of TechnologyGuangzhou 510640China

Oxygen evolution reaction(OER)catalysts are the key core materials that determine the performance of fuel cells,metal-air batteries,electrolytic water decomposition,and other *** this work,a green lignin-based non-precious metal OER catalyst was prepared by a simple ***,c arboxylated lignin was used to complex Ni and Co in situ,and then they were placed with sodium hypophosphite in the same tube furnace for upstream and downstream high-temperature calcination to construct a lignin carbon-based Ni-Co bimetallic OER catalyst(NiCoP@C).The synthesized catalyst is a porous bimetallic phosphide with a three-dimensional network structure and high-density electrochemical active ***@C exhibited favorable catalytic activity for the oxygen evolution reaction(OER)with overpotential of 280 mV at 10 mA·cm~(-2)and a Tafel slope of 77 mV·dec~(-1).Additionally,it exhibited remarkable durability during *** functional theory(DFT)calculations revealed that by leveraging the distinctive structure of transition metal phosphide nanoparticles incorporated into a reticulated substrate,the NiCoP@C catalyst offered an increased number of active sites for OER catalysis,significantly enhancing its stability during practical *** present study broadens the utilization pathways of biomass to"turn waste into treasure,"aligning the development concept of green sustainable development.

关键词： Oxygen evolution reaction Lignin Carbon-based catalyst Nickel-cobalt bimetal Metal phosphide

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Material Removal Mechanism and Force Modeling in Ultrasonic Vibration-Assisted Micro-Grinding Biological Bone

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Chinese Journal of mechanical engineering 2023年第5期36卷 20-44页

作者： Jingang Sun Changhe Li Zongming Zhou Bo Liu Yanbin Zhang Min Yang Teng Gao Mingzheng Liu Xin Cui Benkai Li Runze Li Yusuf Suleiman Dambatta Shubham Sharma School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China Hanergy(Qingdao)Lubrication Technology Co. Ltd.Qingdao 266520China Sichuan Future Aerospace Industry LLC. Shifang 618400China Department of Biomedical Engineering University of Southern CaliforniaLos AngelesCA 90089USA Mechanical Engineering Department Ahmadu Bello UniversityZaria 810106Nigeria Department of Mechanical Engineering and Advanced Materials Science Regional Center for Extension and DevelopmentCouncil of Scientifc and Industrial Research(CSIR)-Central Leather Research Institute(CLRI)Jalandhar 144021India

Micro-grinding with a spherical grinding head has been deemed an indispensable method in high-risk surgeries, such as neurosurgery and spine surgery, where bone grinding has long been plagued by the technical bottleneck of mechanical stress-induced crack damage. In response to this challenge, the ultrasound-assisted biological bone micro-grinding novel process with a spherical grinding head has been proposed by researchers. Force modeling is a prerequisite for process parameter determination in orthopedic surgery, and the difculty in establishing and accurately predicting bone micro-grinding force prediction models is due to the geometric distribution of abrasive grains and the dynamic changes in geometry and kinematics during the cutting process. In addressing these critical needs and technical problems, the shape and protrusion heights of the wear particle of the spherical grinding head were frst studied, and the gradual rule of the contact arc length under the action of high-speed rotating ultrasonic vibration was proposed. Second, the mathematical model of the maximum thickness of undeformed chips under ultrasonic vibration of the spherical grinding head was established. Results showed that ultrasonic vibration can reduce the maximum thickness of undeformed chips and increase the range of ductile and bone meal removals, revealing the mechanism of reducing grinding force. Further, the dynamic grinding behavior of diferent layers of abrasive particles under diferent instantaneous interaction states was studied. Finally, a prediction model of micro-grinding force was established in accordance with the relationship between grinding force and cutting depth, revealing the mechanism of micro-grinding force transfer under ultrasonic vibration. The theoretical model’s average deviations are 10.37% in x-axis direction, 6.85% in y-axis direction, and 7.81% in z-axis direction compared with the experimental results. This study provides theoretical guidance and technical sup

关键词： Spherical grinding head Gradual contact arc length Maximum undeformed chip thickness Microgrinding force

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Functionally graded structure of a nitride-strengthened Mg_(2)Si-based hybrid composite

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Journal of Magnesium and Alloys 2024年第3期12卷 1239-1256页

作者： Jeongho Yang Woongbeom Heogh Hogi Ju Sukhyun Kang Tae-Sik Jang Hyun-Do Jung Mohammad Jahazi Seung Chul Han Seong Je Park Hyoung Seop Kim Susmita Bose Amit Bandyopadhyay Martin Byung-Guk Jun Young Won Kim Dae-kyeom Kim Rigoberto CAdvincula Clodualdo Aranas Jr Sang Hoon Kim School of Mechanical Engineering Pusan National UniversityBusan 46241Republic of Korea Department of Mechanical Design Engineering Hanyang UniversitySeoul 04763Republic of Korea Process Research 3 Team LG Display Co.Ltd.PajuGyeonggi-do 10845Republic of Korea Department of Materials Science and Engineering Chosun UniversityGwangju 61452Republic of Korea Institute of Well-Aging Medicare&Chosun University LAMP Center Chosun UniversityGwangju 61452Republic of Korea Division of Materials Science and Engineering Hanyang UniversitySeoul 04763Republic of Korea Department of Mechanical Engineering École de Technologie SupérieureMontrealQuebec H3C 1K3Canada Material&Component Convergence R&D Center Korea Construction Equipment Technology InstituteGunsanJeollabuk-do 54002Republic of Korea School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore Graduate Institute of Ferrous&Eco Materials Technology Pohang University of Science and TechnologyPohangGyeongsangbuk-do 37673Republic of Korea Advanced Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Institute for Convergence Research and Education in Advanced Technology Yonsei UniversitySeoul 03722Republic of Korea School of Mechanical and Materials Engineering Washington State UniversityPullmanWashington 99164USA School of Mechanical Engineering Purdue UniversityWest LafayetteIndiana 47907USA Research Institute of Advanced Manufacturing Technology Korea Institute of Industrial TechnologyIncheon 21999Republic of Korea Department of Macromolecular Science and Engineering Case Western Reserve UniversityClevelandOhio 44106USA Department of Chemical and Biomolecular Engineering and Joint Institute for Advanced Materials University of TennesseeKnoxvilleTennessee 37996USA Center for Nanophase Materials and Sciences Oak Ridge National LaboratoryOak RidgeTennessee 37830USA Department of Mechanical Engineering University of New BrunswickFrederictonNew Brunswick E3B 5A3Cana

The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in order to provide ultimate wear resistance based on the laser-irradiation-induced inclusion of N_(2) gas during laser powder bed *** is substantialized based on both the thermal diffusion-and chemical reactionbased metallurgy of the Mg_(2)Si–SiC/nitride hybrid *** study also proposes a functional platform for systematically modulating a functionally graded structure and modeling build-direction-dependent architectonics during additive *** strategy enables the development of a compositional gradient from the center to the edge of each melt pool of the Mg_(2)Si–SiC/nitride hybrid ***,the coefficient of friction of the hybrid composite exhibits a 309.3%decrease to–1.67 compared to–0.54 for the conventional nonreinforced Mg_(2)Si structure,while the tensile strength exhibits a 171.3%increase to 831.5 MPa compared to 485.3 MPa for the conventional *** outstanding mechanical behavior is due to the(1)the complementary and synergistic reinforcement effects of the SiC and nitride compounds,each of which possesses an intrinsically high hardness,and(2)the strong adhesion of these compounds to the Mg_(2)Si matrix despite their small sizes and low concentrations.

关键词： Laser powder bed fusion Mg_(2)Si-SiC/nitride hybrid composite Both the thermal diffusion-and chemical reaction-based metallurgy Functionally graded structure Compositional gradient Wear resistance.

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Effect of Surface Roughness on the Magnetism, Nano-indentation, Surface Energy, and Electrical Properties of Co60Fe20Dy20 Films on Si (100) Substrate

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Journal of Electronic materials 2024年第4期53卷 1752-1762页

作者： Liu, Wen-Jen Chang, Yung-Huang Chiang, Chia-Chin Chen, Yuan-Tsung Lin, Chih-Chien Chen, Pei-Ling Lin, Shih-Hung Department of Materials Science and Engineering I-Shou University Kaohsiung840 Taiwan Bachelor Program in Industrial Technology National Yunlin University of Science and Technology 123 University Road Section 3 Yunlin Douliou64002 Taiwan Department of Mechanical Engineering National Kaohsiung University of Science and Technology Kaohsiung City80778 Taiwan Graduate School of Materials Science National Yunlin University of Science and Technology 123 University Road Section 3 Yunlin Douliou64002 Taiwan Department of Electronic Engineering National Yunlin University of Science and Technology 123 University Road Section 3 Yunlin Douliou64002 Taiwan

In this study, we focused on depositing a target material, cobalt-iron-dysprosium (Co60Fe20Dy20), onto silicon (Si) (100) substrates with thickness varying from 10 nm to 50 nm through a direct-current (DC) magnetron sputtering technique. The subsequent step involved subjecting the samples to an hour-long annealing process in a vacuum annealing furnace at temperatures of 100°C, 200°C, and 300°C. To assess the elemental composition of the CoFeDy films, energy-dispersive X-ray spectroscopy (EDS) was employed. An observed trend indicated an increase in low-frequency alternating-current magnetic susceptibility (χac) with the increasing thickness. Remarkably, the CoFeDy films exhibited their peak χac following annealing at 300°C, with an optimal resonance frequency of 50 Hz. After annealing at 300°C, the CoFeDy film’s surface energy peaked at 50 nm. The magnetic, electrical, and adhesive properties of the CoFeDy films were notably influenced by surface roughness at different annealing temperatures. Atomic force microscopy (AFM) analysis revealed a gradual reduction in film roughness post-annealing, corresponding to smoother surfaces indicative of a weaker domain wall pinning effect, heightened carrier conductivity, and increased liquid spreading. Collectively, these outcomes contributed to diminished χac, reduced electrical resistance, and enhanced adhesion. Graphical Abstract: (Figure presented.) © The Minerals, Metals & materials Society 2024.

关键词： Adhesion

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Dynamic deformation behavior of a FeCrNi medium entropy alloy

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Journal of materials science & Technology 2022年第5期100卷 120-128页

作者： Ao Fu Bin Liu Zezhou Li Bingfeng Wang Yuankui Cao Yong Liu State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Department of Mechanical and Aerospace Engineering University of CaliforniaSan DiegoUnited States School of Materials Science and Engineering Central South UniversityChangsha 410083China

Deformation behavior of a FeCrNi medium entropy alloy(MEA)prepared by powder metallurgy(P/M)method was investigated over a wide range of strain *** FeCrNi MEA exhibits high strain-hardening ability,which can be attributed to the multiple deformation mechanisms,including dislocation slip,deformation induced stacking fault and mechanical *** shear localization behavior of the FeCrNi MEA was also analyzed by dynamically loading hat-shaped specimens,and the distinct adiabatic shear band cannot be observed until the shear strain reaches~*** microstructures within and outside the shear band exhibit different characteristics:the grains near the shear band are severely elongated and significantly refined by dislocation slip and twinning;inside the shear band,the initial coarse grains completely disappear,and transform into recrystallized ultrafine equiaxed grains by the classical rotational dynamic recrystallization ***,microvoids preferentially nucleate in the central areas of the shear band where the temperature is very high and the shear stress is highly *** microvoids will coalesce into microcracks with the increase of strain,which eventually leads to the fracture of the shear band.

关键词： Medium entropy alloys mechanical response Dynamic shear properties Grain refinement Adiabatic shear band

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3D-printed auxetic-structured intervertebral disc implant for potential treatment of lumbar herniated disc

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Bioactive materials 2023年第2期20卷 528-538页

作者： Yulin Jiang Kun Shi Luonan Zhou Miaomiao He Ce Zhu Jingcheng Wang Jianhua Li Yubao Li Limin Liu Dan Sun Ganjun Feng Yong Yi Li Zhang Analytical and Testing Center Department of Orthopedic Surgery and Orthopedic Research InstituteSichuan UniversityChengdu610065China School of Materials Science and Engineering Southwest University of Science and TechnologyMianyang621010China Advanced Composite Research Group(ACRG) School of Mechanical and Aerospace EngineeringQueen’s University BelfastBT95AHUK

In this study,a novel artificial intervertebral disc implant with modified“Bucklicrystal”structure was designed and 3D printed using thermoplastic *** new implant has a unique auxetic structure with building blocks joined“face-to-face”.The accompanied negative Poisson’s ratio enables its excellent energy absorption and stability under *** deformation and load distribution behavior of the implant under various loading conditions(bending,torsion,extension and flexion)has been thoroughly evaluated through finite element *** show that,compared to natural intervertebral disc and conventional 3D implant,our new implant exhibits more effective stress transfer and attenuation under practical loading *** implant’s ability to contract laterally under compression can be potentially used to alleviate the symptoms of lumbar disc ***,the biocompatibility of the implant was assessed in vitro and its ability to restore the physiological function of the disc segment was validated in vivo using an animal model.

关键词： Negative Poisson’s ratio Lumbar disc herniation Finite element simulation

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Concurrent hetero-/homo-geneous electrocatalysts to bi-phasically mediate sulfur species for lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第6期93卷 663-668,I0016页

作者： Rui-Bo LingHu Jin-Xiu Chen Jin-Hao Zhang Bo-Quan Li Qing-Shan Fu Gulnur Kalimuldina Geng-Zhi Sun Yunhu Han Long Kong Xi’an Institute of Flexible Electronics(IFE) Northwestern Polytechnical UniversityXi’an 710129ShaanxiChina Institute of Advanced Materials Nanjing Tech UniversityNanjing 211816JiangsuChina Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Department of Mechanical and Aerospace Engineering School of Engineering and Digital SciencesNazarbayev UniversityKabanbay Batyr Ave.53Astana 010000Kazakhstan

Expediting redox kinetics of sulfur species on conductive scaffolds with limited charge accessible surface is considered as an imperative approach to realize energy-dense and power-intensive lithium-sulfur(Li-S)*** this work,the concept of concurrent hetero-/homo-geneous electrocatalysts is proposed to simultaneously mediate liquid-solid conversion of lithium polysulfides(LiPSs)and solid lithium disulfide/sulfide(Li_(2)S_(2)/Li_(2)S)propagation,the latter of which suffers from sluggish reduction kinetics due to buried conductive scaffold surface by extensive deposition of Li_(2)S_(2)/Li_(2)*** selected model material to verify this concept is a two-in-one catalyst:carbon nanotube(CNT)scaffold supported iron-cobalt(Fe-Co)alloy nanoparticles and partially carbonized selenium(C-Se)*** Fe-Co alloy serves as a heterogeneous electrocatalyst to seed Li_(2)S_(2)/Li_(2)S through sulphifilic active sites,while the C-Se sustainably releases soluble lithium polyselenides and functions as a homogeneous electrocatalyst to propagate Li_(2)S_(2)/Li_(2)S via solution *** bi-phasic mediation of the sulfur species benefits reduction kinetics of LiPS conversion,especially for the massive Li_(2)S_(2)/Li_(2)S growth scenario by affording an additional solution directed route in case of conductive surface being largely *** strategy endows the Li-S batteries with improved cycling stability(836 mA h g^(-1)after 180 cycles),rate capability(547 mA h g^(-1)at 4 C)and high sulfur loading superiority(2.96 mA h cm^(-2)at 2.4 mg cm^(-2)).This work hopes to enlighten the employment of bi-phasic electrocatalysts to dictate liquid-solid transformation of intermediates for conversion chemistry batteries.

关键词： Lithium-sulfur batteries Electrocatalysis Lithium polysulfides Sulfur cathode Energy density

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