检索结果-内蒙古大学图书馆

Improving wear and corrosion resistances of Mg_(2)Si/AZ91 composites via tailoring microstructure and intrinsic properties of Mg_(2)Si induced by Sb modification

引用

Journal of Magnesium and Alloys 2024年第11期12卷 4493-4508页

作者： Peng Xiao Yimin Gao Yupeng Sheng Cuicui Yang Zhiwei Liu Yanliang Yi Wenyu Wu Qiqiang Zhao Manoj Gupta State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong UniversityNo.28Xianning West RoadXi'anShaanxi Province 710049PR China Xi'an Modern Chemistry Research Institute Xi'an 710065Shaanxi ProvincePR China Institute of Advance Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhouGuangdong 510632PR China Department of Mechanical Engineering National University of Singapore9 Engineering Drive 1Singapore 117576Singapore

To achieve simultaneous improvement in wear resistance and corrosion resistance,we propose a novel strategy to successfully develop Mg matrix composites containing blocky primary Mg_(2)Si with small size instead of undesirable dendrite shape and large *** tribological and corrosion behavior of Mg_(2)Si/AZ91 unmodified and modified with 2.0wt.%Sb was subsequently and systematically *** results show that Sb addition can significantly modify the morphology of primary Mg_(2)Si to blocky polygon with smaller size of 12-25μm,but has less effect onα-Mg grain *** with unmodified composite,Sb modified Mg_(2)Si/AZ91 composite has higher Brinell hardness and nearly unchanged microhardness of the *** modified composite exhibits a 26%lower wear loss than unmodified composite suggesting the greatly improved wear *** analyses indicate that the main wear mechanism of composites is dominated by abrasive wear,and Sb addition can decrease the width and depth of grooves,resulting in a weakened abrasive wear *** microcracks initiation on Sb modified Mg_(2)Si particles can be restricted during the sliding friction process because of higher toughness and blocky polygonal shape induced by Sb doping,which is responsible for the improved wear ***,Sb modified Mg_(2)Si/AZ91composite also demonstrates a superior corrosion resistance than unmodified composite due to the decrease of calculated corrosion rate from1.57 mm/y to 0.74 mm/y,reduced by 52.8%.Such improvement is closely related to the reduced susceptibility to micro-galvanic corrosion,which is attributed to the reduced volta potential difference of Mg_(2)Si relative to the Mg matrix,from 365 mV to 210 mV.

关键词： Mg matrix composites Morphological regulation Wear resistance Corrosion resistance Sb modification

来源：评论

学校读者我要写书评

暂无评论

Polaron interfacial entropy as a route to high thermoelectric performance in DAE-doped PEDOT:PSS films

引用

National science Review 2024年第3期11卷 259-270页

作者： Jiajia Zhang Caichao Ye Genwang Wei Liang Guo Yuhang Cai Zhi Li Xinzhi Wu Fangyi Sun Qikai Li Yupeng Wang Huan Li Yuchen Li Shuaihua Wang Wei Xu Xuefeng Guo Wenqing Zhang Weishu Liu Department of Materials Science and Engineering Southern University of Science and Technology Academy for Advanced Interdisciplinary Studies and Guangdong Provincial Key Laboratory of Computational Science and Material Design Southern University of Science and Technology Department of Mechanical and Energy Engineering Southern University of Science and Technology Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences College of Chemistry and Molecular Engineering National Biomedical Imaging Centre Peking University Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices Southern University of Science and Technology

Enhancing the thermoelectric transport properties of conductive polymer materials has been a long-term challenge, in spite of the success seen with molecular doping strategies. However, the strong coupling between the thermopower and the electrical conductivity limits thermoelectric performance. Here, we use polaron interfacial occupied entropy engineering to break through this intercoupling for a PEDOT:PSS(poly（3,4-ethylenedioxythiophene）-poly（4-styrenesulfonate）) thin film by using photochromic diarylethene（DAE） dopants coupled with UV-light modulation. With a 10-fold enhancement of the thermopower from 13.5 μV K-1to 135.4 μV K-1and almost unchanged electrical conductivity, the DAE-doped PEDOT:PSS thin film achieved an extremely high power factor of 521.28 μW m-1K-2from an original value of 6.78 μW m-1K-2. The thermopower was positively correlated with the UV-light intensity but decreased with increasing temperature, indicating resonant coupling between the planar closed DAE molecule and PEDOT. Both the experiments and theoretical calculations consistently confirmed the formation of an interface state due to this resonant coupling. Interfacial entropy engineering of polarons could play a critical role in enhancing the thermoelectric performance of the organic film.

关键词： thermoelectric PEDOT: PSS interfacial occupied entropy resonant coupling UV-light modulation

来源：评论

学校读者我要写书评

暂无评论

Wireless, Multifunctional System-Integrated programmable Soft Robot

引用

Nano-Micro Letters 2025年第7期17卷 20-33页

作者： Sungkeun Han Jeong-Woong Shin Joong Hoon Lee Bowen Li Gwan-Jin Ko Tae-Min Jang Ankan Dutta Won Bae Han Seung Min Yang Dong-Je Kim Heeseok Kang Jun Hyeon Lim Chan-Hwi Eom So Jeong Choi Huanyu Cheng Suk-Won Hwang KU-KIST Graduate School of Converging Science and Technology Korea University Semiconductor R&D Center Samsung Electronics Co.Ltd. SK Hynix Department of Engineering Science and Mechanics The Pennsylvania State UniversityUniversity Park Center for Neural Engineering The Pennsylvania State UniversityState CollegeUniversity Park Department of Integrative Energy Engineering Korea University Hanwha Systems Co. Ltd. Department of Materials Science and Engineering The Pennsylvania State UniversityState CollegeUniversity Park Materials Research Institute The Pennsylvania State UniversityState CollegeUniversity Park Center for Biomaterials Biomedical Research InstituteKorea Institute of Science and Technology (KIST) Department of Mechanical Engineering The Pennsylvania State UniversityUniversity Park

Soft robots have partially or entirely provided versatile opportunities for issues or roles that cannot be addressed by conventional machine robots, although most studies are limited to designs, controls, or physical/mechanical motions. Here, we present a transformable, reconfigurable robotic platform created by the integration of magnetically responsive soft composite matrices with deformable multifunctional electronics. Magnetic compounds engineered to undergo phase transition at a low temperature can readily achieve reversible magnetization and conduct various changes of motions and shapes. Thin and flexible electronic system designed with mechanical dynamics does not interfere with movements of the soft electronic robot, and the performances of wireless circuit, sensors, and devices are independent of a variety of activities, all of which are verified by theoretical studies. Demonstration of navigations and electronic operations in an artificial track highlights the potential of the integrated soft robot for on-demand, environments-responsive movements/metamorphoses, and optoelectrical detection and stimulation. Further improvements to a miniaturized, sophisticated system with material options enable in situ monitoring and treatment in envisioned areas such as biomedical implants.

关键词： Reprogrammable magnetic soft robot Soft electronics Soft robotics Untethered multimodal locomotion Wireless

来源：评论

学校读者我要写书评

暂无评论

Dual-single-atoms of Pt-Co boost sulfur redox kinetics for ultrafast Li-S batteries

引用

Carbon Energy 2024年第3期6卷 53-63页

作者： Hanyan Wu Xuejie Gao Xinyang Chen Weihan Li Junjie Li Lei Zhang Yang Zhao Ming Jiang Runcang Sun Xueliang Sun Center for Lignocellulosic Chemistry and Biomaterials College of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalianChina Department of Mechanical and Materials Engineering University of Western OntarioLondonOntarioCanada Institute of Physical Science and Information Technology Anhui UniversityHefeiChina

Applications of lithium-sulfur(Li-S)batteries are still limited by the sluggish conversion kinetics from polysulfide to Li_(2)*** various single-atom catalysts are available for improving the conversion kinetics,the sulfur redox kinetics for Li-S batteries is still not ***,in this work,a catalyst with dual-single-atom Pt-Co embedded in N-doped carbon nanotubes(Pt&Co@NCNT)was proposed by the atomic layer deposition method to suppress the shuttle effect and synergistically improve the interconversion kinetics from polysulfides to Li_(2)*** X-ray absorption near edge curves indicated the reversible conversion of Li_(2)Sx on the S/Pt&Co@NCNT ***,density functional theory demonstrated that the Pt&Co@NCNT promoted the free energy of the phase transition of sulfur species and reduced the oxidative decomposition energy of Li_(2)*** a result,the batteries assembled with S/Pt&Co@NCNT electrodes exhibited a high capacity retention of 80%at 100 cycles at a current density of 1.3 mA cm^(−2)(S loading:2.5 mg cm^(−2)).More importantly,an excellent rate performance was achieved with a high capacity of 822.1 mAh g^(−1) at a high current density of 12.7 mA cm^(−2).This work opens a new direction to boost the sulfur redox kinetics for ultrafast Li-S batteries.

关键词： DFT calculation dual-single-atoms of Pt-Co fast Li-sulfur batteries sulfur redox kinetics XANES analysis

来源：评论

学校读者我要写书评

暂无评论

Elastic microphase separation produces robust bicontinuous materials

引用

Nature materials 2024年第1期23卷 124-130页

作者： Fernández-Rico, Carla Schreiber, Sanjay Oudich, Hamza Lorenz, Charlotta Sicher, Alba Sai, Tianqi Bauernfeind, Viola Heyden, Stefanie Carrara, Pietro Lorenzis, Laura De Style, Robert W. Dufresne, Eric R. Department of Materials ETH Zürich Zürich Switzerland Department of Mechanical and Process Engineering ETH Zürich Zürich Switzerland Adolphe Merkle Institute University of Fribourg Fribourg Switzerland Department of Materials Science and Engineering Department of Physics Cornell University IthacaNY United States

Bicontinuous microstructures are essential to the function of diverse natural and synthetic systems. Their synthesis has been based on two approaches: arrested phase separation or self-assembly of block copolymers. The former is attractive for its chemical simplicity and the latter, for its thermodynamic robustness. Here we introduce elastic microphase separation (EMPS) as an alternative approach to make bicontinuous microstructures. Conceptually, EMPS balances the molecular-scale forces that drive demixing with large-scale elasticity to encode a thermodynamic length scale. This process features a continuous phase transition, reversible without hysteresis. Practically, EMPS is triggered by simply supersaturating an elastomeric matrix with a liquid, resulting in uniform bicontinuous materials with a well-defined microscopic length scale tuned by the matrix stiffness. The versatility of EMPS is further demonstrated by fabricating bicontinuous materials with superior mechanical properties and controlled anisotropy and microstructural gradients. Overall, EMPS presents a robust alternative for the bulk fabrication of homogeneous bicontinuous materials. © 2023, The Author(s), under exclusive licence to Springer Nature Limited.

关键词： Microphase separation

来源：评论

学校读者我要写书评

暂无评论

Improving the strength and surface properties of TNTZ alloy through a combination of high-pressure torsion and laser surface treatment

引用

International Journal of Advanced Manufacturing Technology 2024年第5-6期134卷 2693-2704页

作者： Lin, Hsuan-Kai Hsieh, Tsai-Hsuan Cheng, Yi-Hong Bazarnik, Piotr Wang, Chuan Ting Huang, Yi Ye, Jing Abdelkader, Amor Langdon, Terence G. Department of Materials Engineering National Pingtung University of Science and Technology Pingtung912 Taiwan Faculty of Materials Science and Engineering Warsaw University of Technology Woloska141 02-507 Poland School of Mechanical Engineering Nanjing University of Science and Technology Jiangsu Nanjing210094 China Department of Design and Engineering Faculty of Science and Technology Bournemouth University Dorset PooleBH12 5BB United Kingdom Materials Research Group Department of Mechanical Engineering University of Southampton SouthamptonSO17 1BJ United Kingdom

The Ti–29Nb–13Ta–4.6Zr alloy (TNTZ) is a β-Ti alloy that has a potential for use in biomedical applications as an alternative to the less-compatible Ti64 alloys. Enhancing the strength and the surface finish of TNTZ is essential for biomedical applications. In this research, a combination of high-pressure torsion (HPT) and laser treatment was used to improve the TNTZ properties. The HPT-treated samples showed significantly enhanced mechanical properties when compared with the traditional solution-treated TNTZ. A laser surface treatment immediately forms a hydrophilic surface that transforms into a steady hydrophobic state after 14 days in air and the surface roughness increases with an increase in laser power and a slower scanning rate. The corrosion resistance of TNTZ improves significantly after laser treatment, with the corrosion current dropping from 1 × 10−8 to 1.2 × 10−9 A and the corrosion potential peak shifting to a more positive value from − 0.349 to − 0.158 V. The friction coefficient after laser treatment decreased from 0.134 to 0.093 and then further reduced to 0.082 after 14 days in air thereby suggesting an enhancement in the tribological properties. Overall, the results show that HPT processing combined with a post-HPT laser treatment is beneficial for enhancing the mechanical properties and the corrosion and wear performance of the TNTZ alloy. © The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature 2024.

关键词： Corrosion resistance

来源：评论

学校读者我要写书评

暂无评论

Micromechanical origin of heat transfer to granular flow

引用

Physical Review E 2024年第4期109卷 L042902-L042902页

作者： Xintong Zhang Sarath Adapa Tianshi Feng Jian Zeng Ka Man Chung Clifford Ho Kevin Albrecht Renkun Chen Department of Mechanical and Aerospace Engineering University of California San Diego La Jolla California 92093 USA Program in Materials Science and Engineering University of California San Diego La Jolla California 92093 USA Concentrating Solar Technologies Department Sandia National Laboratories 1515 Eubank Boulevard SE Albuquerque New Mexico 87123 USA

Heat transfer across a granular flow is comprised of two resistances in series : near the wall and within the bulk particle bed, neither of which is well understood due to the lack of experimental probes to separate their respective contribution. Here, we use a frequency modulated photothermal technique to separately quantify the thermal resistances in the near-wall and the bulk bed regions of particles in flowing states. Compared to the stationary state, the flowing leads to a higher near-wall resistance and a lower thermal conductivity of bulk beds. Coupled with discrete element method simulation, we show that the near-wall resistance can be explained by particle diffusion in granular flows.

关键词： Fluidized beds Granular flows Granular materials Granular packing Interparticle interactions

来源：评论

学校读者我要写书评

暂无评论

Challenges and risks of using renewable energy sources 5

Challenges and risks of using renewable energy sources

引用

5th International Conference on Green Energy, Environment, and Sustainable Development, GEESD 2024

作者： Viktoriia, Kozechko Valentyn, Kozechko Department of Mechanical Engineering Technology and Materials Science Dnipro University of Technology Dnipro49000 Ukraine

ISBN: (纸本)9781510683006

The article provides a comprehensive analysis of the transition from traditional energy sources to renewable energy. The article begins by addressing the necessity for stable and cost-effective energy generation while mitigating environmental impacts. Despite the advantages, renewable energy sources often present accessibility and cost challenges compared to fossil fuels, primarily due to lower energy returns and high capital investments. The classification of renewable energy sources into five main types: wind, solar, hydro, bioenergy, and geothermal energy, highlighting their respective advantages and operational limitations. For instance, wind energy is effective in coastal regions but has high initial costs and transmission challenges, while solar energy’s efficiency is weather-dependent. The article delves into barriers to green energy adoption, such as high capital expenditures, decentralized location requirements, transmission costs, grid integration complexities, and the intermittency of renewable sources. It emphasizes the need for significant energy storage solutions to ensure a stable energy supply. Furthermore, the discussion extends to the economic, logistical, and regulatory challenges of decentralized renewable energy systems. The complexities of production, recycling, and disposal of renewable energy components are highlighted, stressing the environmental and economic costs. Also it examines the Energy Return on Investment (EROI) for both traditional and renewable energy sources. Traditional sources like coal, natural gas, hydropower, and nuclear energy exhibit high EROI values, making them more efficient compared to renewable sources, which often have lower EROI due to the energy-intensive processes involved in their production and maintenance. In conclusion, while renewable energy offers significant long-term benefits, the article underscores the need for overcoming initial financial, logistical, and technical challenges to achieve a sustainable en

关键词： Clean energy

来源：评论

学校读者我要写书评

暂无评论

Circular Economy in Healthcare Sector: Cloud-based HST with GT to Minimize Healthcare-associated Infections

Circular Economy in Healthcare Sector: Cloud-based HST with ...

引用

2024 IEEE International Conference on Industrial engineering and engineering Management, IEEM 2024

作者： Alfina, Kartika Nur Chandima Ratnayake, R.M. Bandung Indonesia Department of Mechanical and Structural Engineering and Materials Science University of Stavanger Stavanger Norway

ISBN: (纸本)9798350386097

Healthcare-associated infections (HAIs) pose a significant challenge to the quality of care, leading to patient complications, extended hospital stays, and high consumable costs. Cloud-based technologies have become essential for overcoming barriers to circularity in healthcare, offering transformative opportunities for healthcare systems. Measuring the impact of linear consumption is crucial for circularity, however the healthcare industry lacks focus on measuring the impact of HAIs, particularly related to hand hygiene. Integrating cloud-based hand sanitizer and group technology offers potential to prevent the spread of HAIs and minimize linear consumption, aligning with Circular Economy Goals (CEGs). This study examines the potential of integrating cloud-based HST with group technology (GT) to minimize the impact of HAIs caused by poor hand hygiene. Using the Opitz Code classification system, a coding system is created to measure the impact of poor hand hygiene, serving as a control and improvement tool aligned with CEGs. This article presents an illustrative case to demonstrate the HST coding classification to facilitate predictive analysis for HAIs prevention and control. These findings contribute to reducing HAIs by improving hand hygiene performance in healthcare facilities. Furthermore, by aligning technological advances with CEGs, this study offers a proactive strategy to mitigate environmental degradation by reducing carbon dioxide (CO2) emissions and strengthening the resilience of healthcare systems. © 2024 IEEE.

关键词： Circular economy

来源：评论

学校读者我要写书评

暂无评论

High-speed grinding:from mechanism to machine tool

引用

Advances in Manufacturing 2025年第1期13卷 105-154页

作者： Yu-Long Wang Yan-Bin Zhang Xin Cui Xiao-Liang Liang Run-Ze Li Ruo-Xin Wang Shubham Sharma Ming-Zheng Liu Teng Gao Zong-Ming Zhou Xiao-Ming Wang Yusuf Suleiman Dambatta Chang-He Li School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao266520ShandongPeople’s Republic of China Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE School of Mechanical EngineeringShandong UniversityJinan250061People’s Republic of China Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMAUSA State Key Laboratory of Ultra-precision Machining Technology Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic UniversityHong KongPeople’s Republic of China Department of Mechanical Engineering and Advanced Materials Science Council of Scientific and Industrial Research(CSIR)-Central Leather Research Institute(CLRI)Regional Center for Extension and DevelopmentJalandhar144021India Hanergy(Qingdao)Lubrication Technology Co. Ltd.Qingdao266200ShandongPeople’s Republic of China Department of Mechanical Engineering Ahmadu Bello UniversityZariaNigeria

High-speed grinding(HSG)is an advanced technology for precision machining of difficult-to-cut materials in aerospace and other fields,which could solve surface burns,defects and improve surface integrity by increasing the linear speed of the grinding *** advantages of HSG have been preliminarily confirmed and the equipment has been built for experimental research,which can achieve a high grinding speed of more than 300 m/***,it is not yet widely used in manufacturing due to the insufficient understanding on material removal mechanism and characteristics of HSG machine *** fill this gap,this paper provides a comprehensive overview of HSG technologies.A new direction for adding auxiliary process in HSG is ***,the combined influence law of strain hardening,strain rate intensification,and thermal softening effects on material removal mechanism was revealed,and models of material removal strain rate,grinding force and grinding temperature were ***,the constitutive models under high strain rate boundaries were summarized by considering various properties of material and grinding ***,the change law of material removal mechanism of HSG was revealed when the thermodynamic boundary conditions changed,by introducing lubrication conditions such as minimum quantity lubrication(MQL),nano-lubricant minimum quantity lubrication(NMQL)and cryogenic air(CA).Finally,the mechanical and dynamic characteristics of the key components of HSG machine tool were summarized,including main body,grinding wheel,spindle and dynamic balance *** on the content summarized in this paper,the prospect of HSG is put *** study establishes a solid foundation for future developments in the field and points to promising directions for further exploration.

关键词： High speed grinding(HSG) Material removal mechanism Typical material Lubrication methods Machine tool

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：