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Zinc-Doping-Induced Electronic States Modulation of Molybdenum Carbide: Expediting Rate-Determining Steps of Sulfur Conversion in Lithium-Sulfur Batteries

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Advanced science 2025年第0期 e2417126页

作者： Qin, Bin Li, Yanmei Wang, Qun Zhang, Si Zhang, Jinglin Wang, Bin Wang, Peijia Chen, Yuhan Yao, Weiqi Wang, Fang Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education & School of Chemistry and Materials Science Shanxi Normal University Taiyuan030001 China Shanxi Key Laboratory of Advanced Magnetic Materials and Devices & Research Institute of Materials Science of Shanxi Normal University Taiyuan030001 China Basic Department Shanxi Agricultural University Jinzhong030801 China School of Materials Science and Engineering Harbin Institute of Technology Harbin150001 China Department of Mechanical Engineering City University of Hong Kong 999077 Hong Kong Materials Science and Engineering Program & Texas Materials Institute The University of Texas at Austin AustinTX78712 United States

Enhancing Li2S deposition and oxidation kinetics in lithium-sulfur batteries, especially the potential-limiting step under lean electrolyte, can be effectively achieved by developing conductive catalysts. In this study, by using ZnMoO4 as precursors, Zn-doped molybdenum carbide microflowers (Zn-Mo2C) composed of speared porous sheets are fabricated with a hierarchically ordered structure. Density functional theory calculations indicate that Zn doping shifts the d-band center on Mo atoms in Mo2C upward, promotes the elevation of certain antibonding orbitals in Mo─S bonds above the Fermi level, enhances d-p interaction between lithium polysulfides (LiPSs) and catalysts, weakens both S─S and Li─S bonds of LiPSs. Incorporating Zn significantly reduces the Gibbs free energy barrier for the rate-limiting step of the Li2S2 → Li2S conversion, from 0.52 eV for Mo2C to just 0.05 eV for Zn-doped Mo2C. Thus, the synthesized Zn-Mo2C demonstrates impressive bifunctional electrocatalytic performance, significantly advancing sulfur reduction and Li2S decomposition. Moreover, this modification enhances charge transfer within the Zn-Mo2C/LiPSs system, synergistically accelerating the kinetics of Li2S4 to Li2S reduction and Li2S oxidation. The Zn-Mo2C/S cathode demonstrates impressive electrochemical performance, achieves remarkable cycling stability with a minimal capacity decay of 0.021% per cycle over 1000 cycles at 5 C, underscoring its potential for high-energy applications. © 2025 The Author(s). Advanced science published by Wiley-VCH GmbH.

关键词： Gibbs free energy

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Thermo-economic and environmental evaluation of thin film evaporation using novel metal-organic frameworks to enhance solar desalination performance

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Process Safety and Environmental Protection 2025年 199卷

作者： Sharshir, Swellam W. Abdo, Mohamed R. Yusuf, Kareem El-Naggar, Ahmed A. Joseph, Abanob Ismail, M. Elsaid, Ashraf Mimi El-Samadony, M.O.A. Abdelfatah, Mahmoud El-Shaer, Abdelhamid Yuan, Zhanhui College of Materials Engineering Fujian Agriculture and Forestry University Fuzhou350002 China Mechanical Engineering Department Faculty of Engineering Kafrelsheikh University Kafrelsheikh33516 Egypt Department of Physics and Engineering Mathematics Faculty of Engineering University of Kafrelsheikh Kafrelsheikh Egypt Department of Chemistry College of Science King Saud University Riyadh11451 Saudi Arabia Physics Department Faculty of Science Kafrelsheikh University Kafrelsheikh33516 Egypt Nano Science and Technology Program Faculty of Science Kafrelsheikh University Kafrelsheikh33516 Egypt Department of Mechanical Engineering Faculty of Engineering Suez University SuezP.O. Box 43221 Egypt Refrigeration and Air Conditioning Technology Department Faculty of Technology and Education Helwan University CairoP.O. Box 11282 Egypt Mechanical Power Engineering Department Faculty of Engineering Tanta University Tanta City Egypt

The growing shortage of freshwater resources has spurred the development of innovative and sustainable desalination technologies. This study presents a thermo-economic analysis of an innovative hemispherical solar still (HSS) enhanced with a novel Metal-Organic Framework (MOF), specifically Iron-Aluminum Benzene Tricarboxylate. The MOF was characterized through structural, morphological, and optical investigations and integrated into the HSS using two enhancement methods: (I) as a nanofluid (MOF-NF) at a 1 wt% concentration in the feedwater, and (II) as a heat localization material (MOF-HL) by dispersing it on a black cotton wick that spans the basin surface. An external condenser (EC) was added to further enhance condensation in a subsequent configuration. Three identical HSS systems were used for comparative performance evaluation: a baseline unit (CHSS) and two modified systems, one with a condenser and one without. The results indicated that both MOF-based approaches significantly improved the thermal performance and freshwater yield of the HSS. Notably, the MOF-HL configuration outperformed the MOF-NF configuration across all performance metrics. The configuration designated as MOF-HL-EC achieved the highest rate of freshwater production, with a 96.16 % increase in distillate productivity compared to the CHSS. Additionally, this configuration exhibited exergy and energy efficiencies of 3.18 % and 61.1 %, respectively—improvements of 80.85 % and 95.72 % over the traditional system. Economically, the MOF-HL-EC configuration reduced the production cost of distilled water to 0.0115$ per liter, marking a reduction of 25.29 %. © 2025 The Institution of Chemical Engineers

关键词： Iron analysis

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Influence of submerged arc welding slag content variation on cementitious materials: A sustainable alternative

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Construction and Building Materials 2025年 483卷

作者： Castro-Lopes, S. Rodrigues, V.D. Marden, Sandro Peña-Garcia, R. Padrón-Hernández, E. Berenguer, Romildo Federal Institute of Education Science and Technology of Pará PA Altamira Brazil Laboratory of Composite Materials and Structural Integrity Corrosion and Biocorrosion - CompoLab/LBC Federal University of Pernambuco PE Recife Brazil Federal University of Paraiba Department of Mechanical Engineering PB Joao Pessoa Brazil Federal Rural University of Pernambuco Postgraduate Program in Physics Engineering Academic Unit of Cabo de Santo Agostinho Cabo de Santo PE Agostinho Brazil Federal University of Pernambuco Department of Physics PE Recife Brazil Polytechnic School University of Pernambuco PE Recife Brazil Federal University of Pernambuco Department of Mechanical Engineering PE Recife Brazil

This study evaluates the effects of submerged arc welding (SAW) slag as a partial replacement for Portland cement in cementitious materials. Cement pastes with 5 %, 10 %, 15 %, 20 %, 25 %, and 30 % SAW slag were tested for compressive strength, tensile strength, carbonation resistance, phase formation, and environmental impact. The results revealed that up to 10 % SAW slag significantly enhanced compressive strength, with the 5 % replacement showing a 20.10 % increase in strength at 28 days compared to the control. The mechanical improvement was attributed to the formation of the CSH phase, which was confirmed by X-ray diffraction (XRD) and thermogravimetric analysis (TGA). Carbonation tests indicated that the 5 % SAW samples reduced carbonation by 5 % compared to the control, while the 10 % SAW samples showed a 1 % reduction. This suggests that SAW slag enhances the resistance of cementitious materials to CO2 attack, improving long-term durability. XRD analysis also identified an increase in amorphous phases in the SAW samples, particularly in the 5 % addition, further supporting the pozzolanic activity of SAW slag. Pozzolanic effectiveness coefficient analysis revealed synergistic effects for SAW slag blends, with optimal performance observed at 5 % replacement, in line with microstructural evidence of enhanced CSH gel formation. Environmental analysis demonstrated that replacing 10 % of Portland cement with SAW slag could reduce CO2 emissions by approximately 4564 kg annually, while a 15 % replacement could lead to a reduction of 6846 kg of CO2. These results underscore the potential of SAW slag as a sustainable and performance-enhancing alternative to conventional cement in concrete production. © 2025 Elsevier Ltd

关键词： Compressive strength

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Comparison of CMAS corrosion and sintering induced microstructural characteristics of APS thermal barrier coatings

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Journal of Materials science & technology 2019年第3期35卷 440-447页

作者： Yiyou Wu Hua Luo Canying Cai Yanguo Wang Yichun Zhou Li Yang Guangwen Zhou School of Materials Science and Engineering Xiangtan University Key Laboratory of Low Dimensional Materials & Application Technology of Ministry of Education Xiangtan University Department of Mechanical Engineering & Materials Science and Engineering Program State University of New York at Binghamton

The microstructural features of high-temperature sintered and CaO-MgO-Al_2O_3-SiO_2(CMAS) corroded air plasma sprayed Y_2O_3 stabilized ZrO_2(YSZ) thermal barrier coatings(TBCs) under the thermal gradient condition were comparatively studied. As-sprayed YSZ has a lamellar structure and the lamellae are composed of closely aligned columnar crystals. The sintered and the CMAS corroded YSZ coatings maintain the t'-ZrO_2 phase as the as-sprayed YSZ coating. The sintered YSZ remains the lamellar structure with reduced interlamellar gaps and grains coarsening. After the CMAS corrosion, the top layer of the YSZ coating keeps its lamellar structure consisting of some columnar grains with the CMAS infiltration into the intergrain gaps and the formation of striped Zr_2Y_2 O_7. The typical lamellar structure transforms into more equiaxed grains in the middle and bottom layers of the ceramic coating along with significant infiltration of amorphous CMAS and anorthite formation in the bottom layer owing to the high contents of Ca and Al.

关键词： YSZ thermal barrier coating APS CMAS corrosion Anorthite

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Outcomes of a systems engineering project for K-12 teachers 122

Outcomes of a systems engineering project for K-12 teachers

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2015 122nd ASEE Annual Conference and Exposition

作者： Bartus, Greg Fisher, Frank T. Stevens Institute of Technology Center for Innovation in Engineering and Science Education United States Department of Mechanical Engineering United States Nanotechnology Graduate Program Stevens United States

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Tribology Performance of Silica Nanoparticles as Lubricant Additives in a Reciprocating Four-Stroke Engine Motorcycle

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International Journal of Automotive technology 2023年第2期24卷 435-444页

作者： Lue, Yeou-Feng Hsiao, Wei-Liang Chen, Yi-Shun Undergraduate Program of Vehicle and Energy Engineering National Taiwan Normal University Taipei10610 Taiwan Department of Industrial Education National Taiwan Normal University Taipei10610 Taiwan Department of Mechanical Engineering Asia Eastern University of Science and Technology Taipei22061 Taiwan

Lubricants, such as any types of greases and oils, are usually used to reduce the effect of friction. However, they also have multifunctions that increase the overall performance and application life. To clarify how lubricants decrease friction and reduce friction-related issues, this study evaluated the performance of specific fuel consumption and exhaust emissions (such as hydrocarbon, carbon monoxide, and particulate matter) of motorcycle with nanosilica (nano-SiO2) added to the original lubricant. Lubricants with 0.5, 1.5, 2.5, 3.5, and 4.5 wt.% nano-SiO2 were evaluated after testing their basic properties and conducting tribology tests. The lubricant with 3.5 wt.% nano-SiO2 was the best candidate for the four-stroke engine motorcycle experiments. The results of the tribology experiment with nano-SiO2 lubricant showed that the abrasion loss corresponding to the 3.5 wt.% nano-SiO2 lubricant decreased by an average of 42.43 %. Overall, the 3.5 wt.% nano-SiO2 lubricant improved the effect of lubrication. The primary focus of the current study was the development of nano-SiO2 lubricant technology for applications in industry environments. © 2023, The Korean Society of Automotive Engineers.

关键词： Tribology

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On the Robustness of the xy-Zebra-Gauss-Seidel Smoother on an Anisotropic Diffusion Problem

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Computer Modeling in Engineering & sciences 2018年第11期117卷 251-270页

作者： Michely Laís de Oliveira Marcio Augusto Villela Pinto Simone de Fátima Tomazzoni Goncalves Grazielli Vassoler Rutz Graduate Program in Numerical Methods in Engineering Federal University of Paraná81531-980Curitiba-PRBrazil Department of Mechanical Engineering Federal University of Paraná81531-980Curitiba-PRBrazil Federal Institute of Education Science and Technology of Santa Catarina89813-000Chapecó-SCBrazil.

Studies of problems involving physical anisotropy are applied in sciences and engineering,for instance,when the thermal conductivity depends on the *** this study,the multigrid method was used in order to accelerate the convergence of the iterative methods used to solve this type of *** asymptotic convergence factor of the multigrid was determined empirically(computer aided)and also by employing local Fourier analysis(LFA).The mathematical model studied was the 2D anisotropic diffusion equation,in whichε>0 was the coefficient of a *** equation was discretized by the Finite Difference Method(FDM)and Central Differencing Scheme(CDS).Correction Scheme(CS),pointwise Gauss-Seidel smoothers(Lexicographic and Red-Black ordering),and line Gauss-Seidel smoothers(Lexicographic and Zebra ordering)in x and y directions were used for building the *** best asymptotic convergence factor was obtained by the Gauss-Seidel method in the direction x for 0<ε<<1 and in the direction y forε>>*** this sense,an xy-zebra-GS smoother was proposed,which proved to be efficient and robust for the different anisotropy ***,the convergence factors calculated empirically and by LFA are in agreement.

关键词： Physical anisotropy diffusion problem finite difference method multigrid,local Fourier analysis Gauss-Seidel zebra

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Transient heat transfer in a packed-bed elliptic cylindrical reactor: A finite-volume approach

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Defect and Diffusion Forum 2017年第1期380卷 79-85页

作者： Moura da Silva, R. Barbosa de Lima, A.G. Gomes de Oliveira, L. Vasconcellos Araújo, M. Sousa Santos, R. Federal University of Campina Grande Center of Science and Technology Process Engineering Postgraduate Program Campina Grande Paraíba58429-900 Brazil Federal Institute of Education Science and Technology of Paraíba Princesa Isabel Paraíba58755-000 Brazil Federal University of Campina Grande Center of Science and Technology Mechanical Engineering Department Campina Grande Paraíba58429-900 Brazil Federal University of Campina Grande Center of Science and Technology Chemical Engineering Department Campina Grande Paraíba58429-900 Brazil

This work aims to develop a transient three-dimensional mathematical model using the elliptic cylindrical coordinate system, to predict heat transfer in a elliptic cylindrical packed fixed bed reactor. The model considers variable thermo physical properties and a parabolic temperature profile at the fluid inlet. The governing equation is solved using the finite volume method. Results of temperature profile along the reactor are presented and discussed at different *** was verified that the maximum heat transfer rate inside the reactor occurs near the extreme region close to minor semi-axis of the ellipse;the higher temperatures at the reactor surface are also in this region, along the entire height of the bed;the steady-state regime is reached at t = 4.5 s of process, presenting after this time interval,small axial temperature gradients and high radial gradients along of the reactor bed;the parabolic temperature profile give to the bed a predominance of radial temperature gradients, and the radial porosity profile favours a higher heat transfer rate at reactor surface. © 2017 Trans Tech Publications, Switzerland

关键词： Heat transfer

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Heat transfer analysis for a free boundary problem arising in n-diffusion equation

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Propulsion and Power Research 2016年第4期5卷 261-266页

作者： Ulrich Olivier Dangui-Mbani Jize Sui Chunying Ming Liancun Zheng Goong Chen School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Department of Mathematics and Institute for Quantum Science and Engineermg Texas A&M UniversityCollege StationTX 77843USA Science Program Texas A&M University at QatarEducation CityDohaQatar

This paper presents research on a free boundary value problem arising in a nonlinear n-diffiision equation by using a homotopy analysis method(HAM).Approximate analytical solutions are obtained for special nonlinear diffusion functional coefficient(variable thermal conduction)k(s)=s{i}for i=1,3,5 and convection functional coefficient h(s)=s{j}for j=1,4 and power law parameter of n=0.2,0.5,1.0,*** and efficiency of the approximate solutions are verified by numerical ones showing good *** effects of the power law exponent,the nonlinear diffusion or convection functional coefficients,and the free boundary'parameter on the flux transport characteristics are presented graphically and analyzed in *** mathematical techniques employed in this paper have the significance in studying some other problems of engineering.

关键词： n-Diffusion equation Free boundary Homotopy analysis method Non-linear problem Approximate solution

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Using technology-mediated collaboration in the teaching of ethics & globalization

Using technology-mediated collaboration in the teaching of e...

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2010 ASEE Annual Conference and Exposition

作者： Chinn, Gary Raman, Veena Walton, Steve A. Litzinger, Thomas College of Engineering Pennsylvania State University United States Departments of Communication Arts and Sciences and Science Technology and Society Pennsylvania State University United States Science Technology and Society Program Pennsylvania State University United States Departments of Mechanical Engineering Center for the Enhancement of Engineering Education Pennsylvania State University United States

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