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Electronic Components and Technology Conference (ECTC)

作者： Dylan J. Richmond Emuobosan Enakerakpo Mohammed Alhendi Peter McClure Mark D. Poliks Materials Science &#x0026 Engineering Program Binghamton University Binghamton NY Department of Systems Science Industrial Engineering Binghamton University Binghamton NY Universal Instruments Corporation Conklin NY

Damage and defects that occur in printed circuit board assembly (PCBA) often lead to the disposal of expensive components. In cases where laminate and circuitry have been removed, traditional repairs in the manufacturing process have not been able to return devices into service. This study examines the use of aerosol jet printing (AJP) and traditional engineering fluid dispensing (EFD) as methods to service repairs of damaged *** mount component failures on PCBAs may occur as a result of a bad solder joint or problems with the component. In order to salvage such a PCBA, the component must be physically removed from the board and a new be attached. During the removal of PCBA components, pad cratering may occur, where the pad and laminate are damaged/removed along with the component. This leaves behind a crater in place of the pad, rendering the board unrepairable and thus, unusable. Trace damage is another common failure in PCBs. A repair to either sort of damage often requires reconnections of intricate circuitry to be made. Trace repair has traditionally been serviced by soldering a wire between the undamaged regions, rerouting the connection. In the case of fine conductive traces, as seen in devices which are becoming smaller as heterogeneous packaging innovations continue to progress, traditional methods will not be able to service this sort of *** jet printing, a direct-write additive manufacturing process commonly used in flexible hybrid electronics, could save expensive PCBs by repairing cratered pads and damaged traces. The use of AJP has been successful in repairing damaged modules, however the process has not been optimized for general repairs on FR4. The use of AJP and EFD to repair damaged circuitry on FR4 laminate and to fill pad craters with copper nanoparticle ink is demonstrated. Copper ink structures are uniformly sintered to achieve a solderable surface and good adhesion to the exposed laminate and remaining copper on the PCB. P

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Experimental evidence of crystal-field, Zeeman-splitting, and spin-phonon excitations in the quantum supersolid Na2BaCo(PO4)2

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Physical Review B 2025年第15期111卷 155129-155129页

作者： Ghulam Hussain Jianbo Zhang Man Zhang Lalit Yadav Yang Ding Changcheng Zheng Sara Haravifard Xiawa Wang Division of Natural and Applied Sciences Duke Kunshan University Kunshan Jiangsu 215316 China Center for High-Pressure Science and Technology Advanced Research Beijing 100094 China Department of Physics Duke University Durham North Carolina 27708 USA Department of Mechanical Engineering and Materials Science Duke University Durham North Carolina 27708 USA

Drawing inspiration from the recent breakthroughs in the Na2BaCo(PO4)2 quantum magnet, renowned for its spin supersolidity phase and its potential for solid-state cooling applications, our study delves into the interplay among lattice, spin, and orbital degrees of freedom within this compound. Using temperature-, field-, and pressure-dependent Raman scattering techniques, we present experimental evidence revealing crystal-electric-field (CEF) excitations, alongside the interplay of CEF-phonon interactions. We performed density functional theory calculations for the phonon frequencies and compared them with the experimentally observed modes. In addition, our experiments elucidated electronic transitions from j1/2 to j3/2 and from j1/2 to j5/2, with energy levels closely aligned with theoretical predictions based on point-charge models. Moreover, the application of a magnetic field and pressure revealed Zeeman splittings characterized by Landé-g factors as well as the CEF-phonon resonances. The anomalous shift in the coupled peak at low temperatures originated from the hybridization of CEF and phonon excitations due to their close energy proximity and shared symmetry. These findings constitute a significant step towards unraveling the fundamental properties of this exotic quantum material for future research in fundamental physics or engineering application.

关键词： Degrees of freedom (mechanics)

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Second law of thermodynamics: Spontaneous cold-to-hot heat transfer in a nonchaotic medium

arXiv

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arXiv 2023年

作者： Qiao, Yu Shang, Zhaoru Program of Materials Science and Engineering University of California La Jolla San DiegoCA92093 United States Department of Structural Engineering University of California La Jolla San DiegoCA92093-0085 United States

It has long been known that, fundamentally different from a large body of rarefied gas, when a Knudsen gas is immersed in a thermal bath, it may never reach thermal equilibrium. The root cause is nonchaoticity: as the particle-particle collisions are sparse, the particle trajectories tend to be independent of each other. Usually, this counterintuitive phenomenon is studied through kinetic theory and is not considered a thermodynamic problem. In current research, we show that if incorporated in a compound setup, such an intrinsically nonequilibrium behavior has nontrivial consequences and cannot circumvent thermodynamics: cold-to-hot heat transfer may happen spontaneously, either continuously (with an energy barrier) or cyclically (with time-dependent entropy barriers). It allows for production of useful work by absorbing heat from a single thermal reservoir without any other effect. As the system obeys the first law of thermodynamics, it breaks the boundaries of the second law of thermodynamics. © 2023, CC BY.

关键词： Energy barriers

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Hydrogen Powered Fuel Cell Systems - A Review

Hydrogen Powered Fuel Cell Systems - A Review

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IEEE International Conference on Emerging & Sustainable Technologies for Power & ICT in a Developing Society (NIGERCON)

作者： Sunday A. Afolalu Temitayo S. Ogedengbe Moses E. Emetere Stella I. Monye Monye N. Snow Dept. of Mechanical and Mechatronics Engineering Department Afe Babalola University Ado-Ekiti Nigeria Dept. of Mechanical Science University Johannesburg South Africa Dept. of Mechanical Engineering Department Nile University of Nigeria Abuja Dept. of Physics Program. Bowen University Iwo Osun State Nigeria Dept. of Information Communication Technology University of Delta Agbor Delta State Nigeria

ISBN: (数字)9798331542559

ISBN: (纸本)9798331542566

The urgent need for sustainable energy sources has fuelled research into alternative power generation technologies. Among these, hydrogen fuel cells have emerged as promising candidates due to their high energy efficiency and zero-emission profile. This study presents a review on hydrogen energy and fuel cell. The design principles for fuel cells, hydrogen production methods, hydrogen storage technologies and the integration of fuel cells into power systems have been discussed. The review concludes with a discussion on technological advances in fuel cell materials and environmental impacts/sustainability of hydrogen fuel cells.

关键词： Renewable energy sources Humanities Hydrogen storage Reviews Hydrogen Fuel cells Production Power systems Sustainable development Power generation

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Nanoarchitectonics of europium vanadate nanoparticles decorated carbon nanofibers for electrochemical detection of fungicide in fruits

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Journal of the Taiwan Institute of Chemical Engineers 2024年 161卷

作者： Huang, Song-Jeng Gokulkumar, Kumar Govindasamy, Mani Albaqami, Munirah D. Wabaidur, Saikh Mohammad Department of Mechanical Engineering National Taiwan University of Science and Technology Taipei City106335 Taiwan Department of Research and Innovation Saveetha School of Engineering SIMATS Chennai602105 India International Ph.D. Program in Innovative Technology of Biomedical Engineering and Medical Devices Ming Chi University of Technology New Taipei City243303 Taiwan Department of Chemistry College of Science King Saud University Riyadh11451 Saudi Arabia

Background: Fungicides, like carbendazim, have effects on male fertility. There have been sufficient studies conducted on certain chemical compounds to indicate a selective action at the epididymis level. To prevent contamination of food products with fungicides, most of the governments have established rules for the use of fungicides. However, even though this type of fungicide is primarily used in agriculture. More probably, it's contaminated with fruits and vegetables. In particular, carbendazim is one of the major fungicides in the agricultural usage Methods: This research work developed a europium vanadate (EuVO4) nanoparticle decorated carbon nanofiber (CNF) composites by hydrothermal-sonochemical approach. Based on this composite, Carbendazim sensing is developed through electrochemical oxidation based on EuVO4/f-CNF modified Glassy Carbon Electrode (GCE). By combining EuVO4 and f-CNF with the GCE, carbendazim detection can be highly effective. GCEs are rigid, making them ideal for depositing EuVO4/f-CNF, while their expansive surface area makes it possible to immobilize a greater amount of EuVO4/f-CNF, which could increase the Carbendazim sensing ability of the resulting modified GCEs with EuVO4/f-CNF. Main Findings: : The carbendazim sensing was actualized by the electrocatalytic oxidation of carbendazim on the composite modified electrode, and it is demonstrating a linear range of 0.125 to 23.875 – 33.81 to 131.375 µM with a remarkably limit of detection of 0.00612 µM. The EuVO4/f-CNF /GCE also showcased an excellent degree of stability, retaining 96.5 % of its initial activity even after 30 days. This research highlights the potential of EuVO4/f-CNF modified GCEs as robust, and efficient platform for the carbendazim detection under electrochemical approach. © 2024 Taiwan Institute of Chemical Engineers

关键词： Carbon nanofibers

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Nanoindentation creep of supercrystalline nanocomposites

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materials and Design 2023年第1期231卷

作者： Yan, Cong Bor, Büsra Plunkett, Alexander Domènech, Berta Maier-Kiener, Verena Giuntini, Diletta Department of Mechanical Engineering Eindhoven University of Technology Netherlands Institute of Advanced Ceramics Hamburg University of Technology Germany ams-OSRAM International GmbH ams OSRAM Group Germany Department of Materials Science Montanuniversität Leoben Austria

Supercrystalline nanocomposites (SCNCs) are inorganic-organic hybrid materials with a unique periodic nanostructure, and thus they have been gaining growing attention for their intriguing functional properties and parallelisms with hierarchical biomaterials. Their mechanical behavior remains, however, poorly understood, even though its understanding and control are important to allow SCNCs’ implementation into devices. An important aspect that has not been tackled yet is their time-dependent deformation behavior, which is nevertheless expected to play an important role in materials containing such a distribution of organic phase. Hereby, we report on the creep of ceramic-organic SCNCs with varying degrees of organic crosslinking, as assessed via nanoindentation. Creep strains and their partial recoverability are observed, hinting at the co-presence of viscoelasticity and viscoplasticity, and a clear effect of crosslinking in decreasing the overall material deformability emerges. We rationalize our experimental observations with the analysis of stress exponent and activation volume, resulting in a power-law breakdown behavior and governing deformation mechanisms occurring at the organic sub-nm interfaces scale, as rearrangement of organic ligands. The set of results is reinforced by the evaluation of the strain rate sensitivity via strain rate jump tests, and the assessment of the effect of oscillations during continuous stiffness measurement mode. © 2023 The Author(s)

关键词： Nanocomposites

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Electro osmotically flow of fourth-grade fluid in complex channel with porous medium and lubricated walls: applications in petroleum industry

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Waves in Random and Complex Media 2023年

作者： Nazeer, Mubbashar Pasha, Amjad Ali Hussain, Farooq Adil, Mohammad Mechanical Engineering Program Physical Science and Engineering Division King Abdullah University of Science and Technology Thuwal Saudi Arabia BUITEMS Quetta Pakistan KAUST Clean Combustion Research Center King Abdullah University of Science and Technology Thuwal Saudi Arabia Department of Mathematics Institute of Arts and Sciences Government College University Faisalabad Chiniot Campus Pakistan Aerospace Engineering Department King Abdulaziz University Jeddah Saudi Arabia

This article offers a distinct survey of a multiphase flow through a uniform channel. The electro-osmotic phenomenon is the main source of the flow. Fourth-grade fluid model is used as the base liquid which is suspended with metallic particles to form a bi-phase viscous suspension. Skin friction effects are tackled by employing lubrication effects on the opposite walls of the channel. Porous media is governed by the modified Darcy’s law and the Poisson differential equation is considered for electric double-layer effects. An approximate solution is achieved for the nonlinear fluid flow. The obtained findings are also compared with the existing literature for the limiting case. It is inferred that the shear thickness effects cause the momentum of the bi-phase flow to decline, gradually. However, the motion of the metallic particles is supported by the lubrication effects on the walls of the channel. © 2023 Informa UK Limited, trading as Taylor & Francis Group.

关键词： Porous materials

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First-Principles and Cluster Expansion Study of the Effect of Magnetism on Short-Range Order in Fe-Ni-Cr Austenitic Stainless Steels

SSRN

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SSRN 2024年

作者： Su, Tianyu Blankenau, Brian J. Kim, Namhoon Krogstad, Jessica A. Ertekin, Elif Department of Materials Science and Engineering University of Illinois at Urbana-Champaign 1304 W. Green Street UrbanaIL61801 United States Department of Mechanical Science and Engineering University of Illinois at Urbana-Champaign 1206 W. Green Street UrbanaIL61801 United States Materials Research Laboratory University of Illinois at Urbana-Champaign 104 South Goodwin Avenue UrbanaIL61801 United States Frederick Seitz Materials Research Laboratory

Short-range order (SRO) alters the mechanical properties of technologically relevant structuralmaterials such as medium/high entropy alloys and austenitic stainless steels. In thisstudy, we present a generalized spin cluster expansion (CE) model and show that magnetism is a primary factor influencing the level of SRO present in austenitic Fe-Ni-Cr alloys. The spin CE consists of a chemical cluster expansion combined with an Ising model for Fe-Ni-Cr alloys. It explicitly accounts for local magnetic exchange interactions, thereby capturing the effects of finite temperature magnetism on SRO. Model parameters are obtained by fitting to a first-principles data set comprising both chemically and magnetically diverse FCC configurations. The magnitude of the magnetic exchange interactions are found to be comparable to the chemical interactions. Compared to a conventional implicit magnetism CE built from only magnetic ground state configurations, the spin CE shows improved performance on several experimental benchmarks over a broad spectrum of compositions, particularly at higher temperatures due to the explicit treatment of magnetic disorder. We find that SRO is strongly influenced by alloy Cr content, since Cr atoms prefer to align antiferromagnetically with nearest neighbors but become magnetically frustrated with increasing Cr concentration. We predict that increasing the Cr concentration in typical austenitic stainless steels promotes the formation of SRO and increases order-disorder transition temperatures. This study underscores the significance of considering magnetic interactions explicitly when exploring the thermodynamic properties of complex transition metal alloys. It also highlights guidelines for customizing SRO through adjustments of alloy composition. © 2024, The Authors. All rights reserved.

关键词： Ground state

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Sensing property of Ga2O3-based extended-gate field-effect transistors for a living cell viability sensor

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Sensors and Actuators A: Physical 2023年 349卷

作者： Chou, Hsin-Yu Chiang, Jung-Lung Yu, Chang-Tze Ricky Chen, Jo-Mei Maureen Wuu, Dong-Sing Department of Materials Science and Engineering National Chung Hsing University Taichung40227 Taiwan Ph.D. Program Prospective Technology of Electrical Engineering and Computer Science National Chin-Yi University of Technology Taichung411030 Taiwan Department of Applied Chemistry National Chi-Nan University Nantou54561 Taiwan Department of Applied Materials and Optoelectronic Engineering National Chi Nan University Nantou54561 Taiwan

In this study, gallium oxide (Ga2O3) nanorods were deposited onto an indium tin oxide (ITO) glass substrate to develop a real-time living cell viability sensor. Ga2O3 nanorods had characteristics of cell population sensing based on cellular metabolism to detect cell viability. The pH sensing characteristics of Ga2O3-based extended-gate field-effect transistors (EGFETs) with and without the annealing process were measured from pH 1–11. Three different sensor heads, ITO/glass, GaOOH/ITO/glass, and Ga2O3/ITO/glass, were produced as EGFETs and immersed into a pH standard buffer and high-glucose Dulbecco's modified Eagle's medium (DMEM) to investigate hydrogen ion sensing. Results showed that the Ga2O3/ITO/glass probe had the best hydrogen ion sensing sensitivity and stability in different sample buffers. In contrast, GaOOH/ITO/glass had instability and lower sensitivity due to interference with other components in the medium. The drift characteristic of sensors was analyzed to detect long-term stability. The Ga2O3/ITO/glass probe showed lower drift properties, which can potentially monitor the DMEM situation in real-time for a long-term period. During in vitro detection, the Ga2O3/ITO/glass probe revealed a 70 μA/cells change in IDS-VDS analysis and a 10 μV/cells change in IDS-VGS analysis, which was superior linearly dependent within 10,000 cells. The biocompatibility of the Ga2O3/ITO/glass probe was also detected by 3-(4,5-dimethylthiazol-2-yl)− 2,5-diphenyltetrazolium bromide assay and showed no cytotoxicity. Overall, the Ga2O3/ITO/glass EGFET sensor has potential applications as a living cell viability device in microenvironmental studies in the future. © 2022 Elsevier B.V.

关键词： Nanorods

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Gradient Design with Low-Tortuosity Overcoming Kinetic Limitations in High-Loading Solid-State Cathodes

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Angewandte Chemie 2025年

作者： Guangzeng Cheng Jinping Yu Yonghui Wang Zhengyu Ju Yue Zhu Weiqian Tian Jingwei Chen Huanlei Wang Jingyi Wu Guihua Yu School of Materials Science and Engineering Ocean University of China Qingdao 266404 China Materials Science and Engineering Program and Walker Department of Mechanical Engineering The University of Texas at Austin Austin Texas 78712 USA

The extensive commercialization of practical solid-state batteries (SSBs) necessitates the development of high-loading solid-state cathodes with fast charging capability. However, electrochemical kinetics are severely delayed in thick cathodes due to tortuous ion transport pathways and slow solid-solid ion diffusion, which limit the achievable capacity of SSBs at high current densities. In this work, we propose a conductivity gradient cathode with low-tortuosity to enable facile ion transport and counterbalance ion concentration gradient, thereby overcoming the kinetic limitations and achieving fast charging capabilities in thick cathodes. The LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathodes deliver a room-temperature (RT) capacities of 147 and 110 mAh g −1 at 5 C and 10 C, respectively, and meanwhile achieve a RT areal capacity of 3.3 mAh cm −2 at 3 C, enabling SSBs simultaneously high energy and power densities. The universality of this strategy is demonstrated in LiFePO 4 cathodes, providing a novel solution for fast charging and large-scale application of high-loading SSBs.

关键词： solid-state battery composite cathode high-loading gradient low-tortuosity

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