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Journal of Magnesium and Alloys 2024年第5期12卷 1931-1943页

作者： Farid Bahari-Sambran Fernando Carre?o C.M.Cepeda-Jiménez Alberto Orozco-Caballero Physical Metallurgy department CENIM-CSIC department of Mechanical Engineering Chemistry and Industrial Design Polytechnic University of Madrid

The aim of this work is to predict, for the first time, the high temperature flow stress dependency with the grain size and the underlaid deformation mechanism using two machine learning models, random forest（RF） and artificial neural network（ANN）. With that purpose, a ZK30 magnesium alloy was friction stir processed（FSP） using three different severe conditions to obtain fine grain microstructures（with average grain sizes between 2 and 3 μm） prone to extensive superplastic response. The three friction stir processed samples clearly deformed by grain boundary sliding（GBS） deformation mechanism at high temperatures. The maximum elongations to failure, well over 400% at high strain rate of 10-2s-1, were reached at 400 ℃ in the material with coarsest grain size of 2.8 μm, and at 300 ℃ for the finest grain size of 2 μm. Nevertheless, the superplastic response decreased at 350 ℃ and 400 ℃ due to thermal instabilities and grain coarsening, which makes it difficult to assess the operative deformation mechanism at such temperatures. This work highlights that the machine learning models considered, especially the ANN model with higher accuracy in predicting flow stress values, allow determining adequately the superplastic creep behavior including other possible grain size scenarios.

关键词： Machine learning Artificial intelligence Magnesium alloys Superplasticity Friction stir processing Grain coarsening

In Situ Analysis of Tobacco Leaves Based on Microwave Plasma Torch Desorption Ionization Mass Spectrometry

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Journal of Analysis and Testing 2024年第1期8卷 9-15页

作者： He Tang Yonggang Zhang Zhiguang Reng Junchen Zhu Yue Xie Xiaobin Zhang Hongru Feng Kailong Yuan Yuanjiang Pan department of chemistry Zhejiang UniversityHangzhou 310027China Zhejiang China Tobacco industrial Co. Ltd.Hangzhou310008China

Tobacco is an important economic crop *** leaves contain a large number of natural ***,the analysis of tobacco composition is crucial for the control of tobacco safety and quality *** plasma torch desorption ionization mass spectrometry(MPT-MS) is an emerging ambient mass spectrometry(AMS) technique that can be used for rapid real-time analysis of s amples without *** work focuses on the chemical composition analysis of tobacco using MPT-MS,and 14 compounds were detected in green flue-cured tobacco leaves,while 30 compounds were detected in cured flue-cured tobacco leaves,which confirms that curing can enhance the flavor of ***,we successfully in situ identified characteristic fragment ions of α/β-CBD(α/β-cembranoids),an important aroma compound in tobacco by *** results demonstrate the capability of MPT-MS for in situ analysis of tobacco components and its potential for evaluating tobacco quality.

关键词： Microwave plasma torch Ambient mass spectrometry Tobacco α/β-Cembranoids

Electrochemical reduction of carbon dioxide to produce formic acid coupled with oxidative conversion of biomass

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Journal of Energy chemistry 2024年第5期92卷 705-729页

作者： Xi Liu Yifan Wang Zhiwei Dai Daihong Gao Xuebing Zhao Key Laboratory of industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Institute of Applied chemistry Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Electrochemical reduction of CO_(2)(CO_(2)RR)has become a research hot spot in recent years in the context of carbon *** is one of the most promising products obtained by electrochemical reduction of CO_(2) due to its high energy value as estimated by market price per energy unit and wide application in chemical *** is the most abundant renewable resource in the natural *** biomass oxidative conversion with CO_(2)RR driven by renewable electricity would well achieve carbon *** this work,we comprehensively reviewed the current research progress on CO_(2)RR to produce HCOOH and coupled system for conversion of biomass and its derivatives to produce value-added ***-and Bi-based electrocatalysts are discussed for CO_(2)RR with regards to the structure of the catalyst and reaction ***-oxidation reactions of biomass derived sugars,alcohols,furan aldehydes and even polymeric components of lignocellulose were reviewed as alternatives to replace oxygen evolution reaction(OER)in the conventional electrolysis *** was recommended that to further improve the efficiency of the coupled system,future work should be focused on the development of more efficient and stable catalysts,careful design of the electrolytic cells for improving the mass transfer and development of environment-friendly processes for recovering the formed formate and biomass oxidation products.

关键词： Electrochemical reduction of CO_(2) Formic acid Oxidative conversion of biomass Lignocellulose Coupled system

Evaluating innovation ecosystem resiliency using agent-based modeling and systems dynamics

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Journal of Safety Science and Resilience 2024年第2期5卷 204-221页

作者： Soheila Abdi Mehdi Yazdani Esmaeil Najafi department of industrial Engineering Science and Research BranchIslamic Azad UniversityTehranIran department of industrial Engineering Qazvin BranchIslamic Azad UniversityQazvinIran

Evaluating the resilience of the innovation ecosystem to maintain its performance,in the sense of resistance to disruption and recovery after it,has recently received more *** studies have been conducted to model different ecosystems and evaluate their ***,modeling the innovation ecosystem from a holistic perspective and performing a quantitative assessment of its resilience have received less *** paper models the innovation ecosystem holistically and evaluates its resilience index using a quantitative approach through five main *** the first step,a case study related to the innovation ecosystem of Iran's Ministry of Energy,called the Power Innovation Ecosystem,is modeled by combining system dynamics and agent-based *** validating the model in the second step,the disruption of the loss of experts is investigated in the third step,and all possible actions to recover each actor are *** the fourth step,the performance of the ecosystem is simulated before and after the disruption using the data gathered in the previous ***,resilience is calculated in two different ways in the fifth *** improvement solutions are also suggested when considering that the resilience index of the innovation ecosystem is at a medium *** research may assist policymakers in observing the resilience level of the innovation ecosystem based on the proposed *** applying strategic changes to this model,they can determine the effects of their policies and make the most appropriate decisions to increase the resilience of the innovation ecosystem.

关键词： Resilience index innovation ecosystem System dynamics Agent-based modeling

Porous garnet as filler of solid polymer electrolytes to enhance the performance of solid-state lithium batteries

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Nano Research 2024年第4期17卷 2663-2670页

作者： Yang Zhang Lei Zhang Peng Guo Chaoyan Zhang Xiaochuan Ren Zhen Jiang Jianjun Song Chuan Shi College of Physics Qingdao UniversityQingdao 266071China industrial Research Institute of Nonwovens and Technical Textiles College of Textiles and ClothingQingdao UniversityQingdao 266071China department of chemistry University of PennsylvaniaPhiladelphiaPA 19104USA

In order to enhance the ionic conductivity of solid polymer electrolytes(SPEs)and their structural rigidity against lithium dendrite during lithium-ion battery(LIB)cycling,we propose porous garnet Li6.4La3Zr2Al0.2O12(LLZO),as the filler to *** porous LLZO with interlinked grains was synthesized via a resol-assisted cationic coordinative co-assembly *** porous structure of LLZO with high specific surface area facilitates the interaction between polymer and filler and provides sufficient entrance for Li^(+)migration into the LLZO ***,the interconnection of LLZO grains forms continuous inorganic pathways for fast Li^(+)migration,which avoid the multiple diffusion for Li^(+)in *** a result,the SPEs with porous LLZO(SPE-PL)show a high ionic conductive of 0.73 mS·cm^(-1) at 30℃ and lithium-ion transference number of *** porous LLZO with uniformly dispersed pores also acts as an ion distributor to regulate ionic *** lithium-symmetrical batteries assembled with SPE-PL show a highly stable Li plating/stripping cycling for nearly 3000 h at 0.1 mA·cm^(-2).The corresponding Li/LiFePO_(4) batteries also exhibit excellent cyclic performance with capacity retention of 75%after nearly 500 *** work brings new insights into the design of conductive fillers and the optimization of SPEs.

关键词： solid polymer electrolytes lithium metal battery porous conductive filler solid state battery

Tribological behavior of shape-specific microplate-enriched synovial fluids on a linear two-axis tribometer

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Friction 2024年第3期12卷 539-553页

作者： Agnese FRAGASSI Antonietta GRECO Martina DI FRANCESCO Luca CESERACCIU Aiman ABU AMMAR Israel DVIR Thomas Lee MOORE Haytam KASEM Paolo DECUZZI Laboratory of Nanotechnology for Precision Medicine Fondazione Istituto Italiano di TecnologiaGenova 16163Italy department of chemistry and industrial chemistry University of GenovaGenoa 16146Italy Materials Characterization Facility Istituto Italiano di TecnologiaGenova 16163Italy department of Pharmaceutical Engineering Azrieli College of Engineering JerusalemJerusalem 9103501Israel department of Mechanical Engineering Azrieli College of Engineering JerusalemJerusalem 9103501Israel

Nano-and micro-particles are being increasingly used to tune interfacial frictional properties in diverse applications,from friction modifiers in industrial lubrication to enhanced biological fluids in human osteoarthritic ***,we assessed the tribological properties of a simulated synovial fluid enriched with non-spherical,poly lactic-co-glycolic acid(PLGA)microparticles(μPL)that have been previously demonstrated for the pharmacological management of osteoarthritis(OA).Three different μPL configurations were fabricated presenting a 20μm×20μm square base and a thickness of 5μm(thin,5H μPL),10μm(10H μPL),and 20μm(cubical,20H μPL).After extensive morphological and physicochemical characterizations,the apparent Young’s modulus of the μPL was quantified under compressive loading returning an average value of~6 kPa,independently of the particle ***,using a linear two-axis tribometer,the static(μ_(s))and dynamic(μ_(d))friction coefficients of the μPL-enriched simulated synovial fluid were determined in terms of particle configuration and concentration,varying from 0(fluid only)to 6×10^(5) μPL/*** particle morphology had a modest influence on friction,possibly because the μPL were fully squeezed between two mating surfaces by a 5.8 N normal load realizing boundary-like lubrication ***,friction was observed to depend on the dimensionless parameterW,defined as the ratio between the total volume of the μPL enriching the simulated synovial fluid and the volume of the fluid *** coefficients of friction were documented to grow withWreaching a plateau of μ_(s)~0.4 and μ_(d)~0.15,already at Ω~2×10^(-3).Future investigations will have to systematically analyze the effect of sliding velocity,normal load,and rigidity of the mating surfaces to elucidate in full the tribological behavior of μPL in the context of osteoarthritis.

关键词： osteoarthritis microparticles tribology synovial fluid pin on plate

A Multi-Objective Optimization for Locating Maintenance Stations and Operator Dispatching of Corrective Maintenance

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Computers, Materials & Continua 2024年第6期79卷 3519-3547页

作者： Chao-Lung Yang Melkamu Mengistnew Teshome Yu-Zhen Yeh Tamrat Yifter Meles department of industrial Management National Taiwan University of Science and TechnologyTaipie106Taiwan department of industrial Engineering University of Gondar Institute of TechnologyGondar196Ethiopia

In this study,we introduce a novel multi-objective optimization model tailored for modern manufacturing,aiming to mitigate the cost impacts of operational disruptions through optimized corrective *** to our approach is the strategic placement of maintenance stations and the efficient allocation of personnel,addressing a crucial gap in the integration of maintenance personnel dispatching and station *** model uniquely combines the spatial distribution of machinery with the expertise of operators to achieve a harmonious balance between maintenance efficiency and *** core of our methodology is the NSGA Ⅲ+Dispatch,an advanced adaptation of the Non-Dominated Sorting Genetic Algorithm Ⅲ(NSGA-Ⅲ),meticulously designed for the selection of maintenance stations and effective operator *** method integrates a comprehensive coding process,crossover operator,and mutation operator to efficiently manage multiple *** empirical testing,including a detailed analysis from a taiwan region electronic equipment manufacturer,validated the effectiveness of our approach across various scenarios of machine failure frequencies and operator *** findings reveal that the proposed model significantly outperforms current practices by reducing response times by up to 23%in low-frequency and 28.23%in high-frequency machine failure scenarios,leading to notable improvements in efficiency and cost ***,it demonstrates significant improvements in oper-ational efficiency,particularly in selective high-frequency failure contexts,while ensuring substantial manpower cost savings without compromising on operational *** research significantly advances maintenance strategies in production environments,providing the manufacturing industry with practical,optimized solutions for diverse machine malfunction ***,the methodologies and principles developed in this study have pote

关键词： Corrective maintenance multi-objective optimization non-dominated sorting genetic algorithmⅢ operator allocation maintenance station location

On dry machining of AZ31B magnesium alloy using textured cutting tool inserts

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Journal of Magnesium and Alloys 2024年第4期12卷 1608-1618页

作者： Shailendra Pawanr Kapil Gupta department of Mechanical and industrial Engineering Technology University of JohannesburgDoornfontein CampusJohannesburg 2028 South Africa

Magnesium alloys have many advantages as lightweight materials for engineering applications,especially in the fields of automotive and *** undergo extensive cutting or machining while making products out of *** cutting,a sustainable machining method,causes more friction and adhesion at the tool-chip *** of the promising solutions to this problem is cutting tool surface texturing,which can reduce tool wear and friction in dry cutting and improve machining *** paper aims to investigate the impact of dimple textures(made on the flank face of cutting inserts)on tool wear and chip morphology in the dry machining of AZ31B magnesium *** results show that the cutting speed was the most significant factor affecting tool flank wear,followed by feed rate and cutting *** tool wear mechanism was examined using scanning electron microscope(SEM)images and energy dispersive X-ray spectroscopy(EDS)analysis reports,which showed that at low cutting speed,the main wear mechanism was abrasion,while at high speed,it was *** chips are discontinuous at low cutting speeds,while continuous at high cutting *** dimple textured flank face cutting tools facilitate the dry machining of AZ31B magnesium alloy and contribute to ecological benefits.

关键词： Magnesium alloy Dry machining Textured tools Flank wear Sustainability

Design of a large-scale model for wind tunnel test of a multiadaptive flap concept

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Chinese Journal of Aeronautics 2024年第2期37卷 58-80页

作者： Mürüvvet Sinem SICIM DEMIRCI Rosario PECORA Metin Orhan KAYA Aeronautical Engineering department Istanbul Technical UniversityIstanbulTurkey industrial Engineering department University of Naples Federico IINapoliItaly

The design and application of morphing systems are ongoing issues compelling the aviation *** Clean Sky-program represents the most significant aeronautical research ever launched in Europe on advanced technologies for greening next-generation *** primary purpose of the program is to develop new concepts aimed at decreasing the effects of aviation on the environment,increasing reliability,and promoting eco-friendly *** ambitions are pursued through research on enabling technologies fostering noise and gas emissions reduction,mainly by improving aircraft aerodynamic *** the Clean Sky framework,a multimodal morphing flap device was designed based on tight industrial requirements and tailored for large civil aircraft *** flap is deployed in one unique setting,and its cross section is morphed differently in take-off and landing to get the necessary extra lift for the specific flight ***,during the cruise,the tip of the flap is deflected for load control and induced drag *** manufacturing the first flap prototype,a high-speed(Ma=0.3),large-scale test campaign(geometric scale factor 1:3)was deemed necessary to validate the performance improvements brought by this novel system at the aircraft *** the other hand,the geometrical scaling of the flap prototype was considered impracticable due to the unscalability of the embedded mechanisms and actuators for shape ***,a new architecture was conceived for the flap model to comply with the scaled dimensions requirements,withstand the relevant loads expected during the wind tunnel tests and emulate the shape transition capabilities of the true-scale *** strategies were developed to effectively morph the model during wind tunnel tests while ensuring the robustness of each morphed configuration and maintaining adequate stiffness levels to prevent undesirable deviations from the intended aerodynamic ***,

关键词： Morphing structures Smart aircraft Morphing flap Adaptive systems Finger-like ribs Wind tunnel tests Large-scale morphing archi-tectures Variable camber airfoil

Analysis of Supply Chain Sustainability Drivers in the Oil and Gas Industry under Covid-19 Pandemic

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Journal of Systems Science and Systems Engineering 2024年第2期33卷 131-161页

作者： Sujan Piya department of industrial Engineering and Engineering Management University of SharjahSharjahUnited Arab Emirates

The supply chain of many industries,including Oil and Gas,was significantly affected by the disruption caused by the Covid ***,in turn,had a knock-on effect on other industries around the *** the impact of the disruption posed a major challenge for the *** study contributes to the existing literature by identifying and analyzing the most significant drivers that affected the sustainability of the Oil and Gas supply chain during the Covid *** drivers were identified based on an extensive literature review and a survey conducted with experts working in the Oil and Gas ***-criteria decision-making methodologies were used to analyze these *** analysis from the fuzzy analytical hierarchy process found that the most important drivers for the sustainability of the Oil and gas supply chain during the pandemic were"Risk management capacity","Government regulation"and"Health and safety of employees".On the other hand,the driver"Community Pressure"was found to be of the least ***,the study integrated the results of the fuzzy analytical hierarchy process with the fuzzy technique for order of preference by similarity to ideal solution to calculate the supply chain sustainability index.A case example was demonstrated to rank the industries based on such *** study can support the governmental institutions in benchmarking the Oil and Gas industry based on its sustainability ***,the outcomes of the study will help industrial decision makers prioritize the drivers the company should focus and devise strategies based on the priority to improve the sustainability of their supply chain during severe *** will be crucial as the World health organization has cautioned that the world may encounter another pandemic in the near future.

关键词： Supply chain sustainability drivers Oil and gas supply chain Fuzzy analytical hierarchy process Fuzzy technique for order of preference by similarity to ideal solution Covid-19