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Molecular-sized outward-swinging gate: Experiment and theoretical analysis of a locally nonchaotic barrier

Physical Review E 2021年第6期104卷 064133-064133页

作者： Yu Qiao Zhaoru Shang Rui Kou Program of Materials Science and Engineering University of California – San Diego La Jolla California 92093 USA Department of Structural Engineering University of California – San Diego La Jolla California 92093-0085 USA

We investigate the concept of molecular-sized outward-swinging gate, which allows for entropy decrease in an isolated system. The theoretical analysis, the Monte Carlo simulation, and the direct solution of governing equations all suggest that under the condition of local nonchaoticity, the probability of particle crossing is asymmetric. It is demonstrated by an experiment on a nanoporous membrane one-sidedly surface-grafted with bendable organic chains. Remarkably, through the membrane, gas spontaneously and repeatedly flows from the low-pressure side to the high-pressure side. While this phenomenon seems counterintuitive, it is compatible with the principle of maximum entropy. The locally nonchaotic gate interrupts the probability distribution of the local microstates, and imposes additional constraints on the global microstates, so that entropy reaches a nonequilibrium maximum. Such a mechanism is fundamentally different from Maxwell's demon and Feynman's ratchet, and is consistent with microscopic reversibility. It implies that useful work may be produced in a cycle from a single thermal reservoir. A generalized form of the second law of thermodynamics is proposed.

关键词： Classical statistical mechanics Nonequilibrium statistical mechanics Thermodynamics Nonequilibrium systems

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Scientific Machine Learning Framework to Understand Flash Graphene Synthesis

arXiv

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arXiv 2023年

作者： Sattari, Kianoosh Eddy, Lucas Beckham, Jacob L. Wyss, Kevin M. Byfield, Richard Qian, Long Tour, James M. Lin, Jian Department of Mechanical and Aerospace Engineering University of Missouri ColumbiaMO65211 United States Department of Chemistry 6100 Main Street HoustonTX77005 United States Applied Physics Program Smalley-Curl Institute 6100 Main Street HoustonTX77005 United States Department of Materials Science and NanoEngineering 6100 Main Street HoustonTX77005 United States Department of Computer Science and Engineering NanoCarbon Center The Welch Institute for Advanced Materials Rice University 6100 Main Street HoustonTX77005 United States

Flash Joule heating (FJH) is a far-from-equilibrium (FFE) processing method for converting low-value carbon-based materials to flash graphene (FG). Despite its promise in scalability and performance, attempts to explore the reaction mechanism have been limited due to complexity involved in the FFE process. Data-driven machine learning (ML) models effectively account for this complexity, but the model training requires considerable amount of experimental data. To tackle this challenge, we constructed a scientific ML (SML) framework trained by using both direct processing variables and indirect, physics-informed variables to predict the FG yield. The indirect variables include current-derived features (final current, maximum current, and charge density) predicted from the proxy ML models and reaction temperatures simulated from multi-physics modeling. With the combined indirect features, the final ML model achieves an average R2 score of 0.81 ± 0.05 and an average RMSE of 12.1% ± 2.0% in predicting the FG yield, which is significantly higher than the model trained without them (R2 of 0.73 ± 0.05 and an RMSE of 14.3% ± 2.0%). Feature importance analysis validates the key roles of these indirect features in determining the reaction outcome. These results illustrate the promise of this SML to elucidate FFE material synthesis outcomes, thus paving a new avenue to processing other datasets from the materials systems involving the same or different FFE processes. Copyright © 2023, The Authors. All rights reserved.

关键词： Graphene

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Identifying the minimal sets of distance restraints for FRET-assisted protein structural modeling

arXiv

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arXiv 2024年

作者： Liu, Zhuoyi Grigas, Alex T. Sumner, Jacob Knab, Edward Davis, Caitlin M. O’Hern, Corey S. Department of Mechanical Engineering and Materials Science Yale University New HavenCT06520 United States Integrated Graduate Program in Physical and Engineering Biology Yale University New HavenCT06520 United States Graduate Program in Computational Biology and Bioinformatics Yale University New HavenCT06520 United States Department of Chemistry Yale University New HavenCT06520 United States Department of Physics Yale University New HavenCT06520 United States Department of Applied Physics Yale University New HavenCT06520 United States

Proteins naturally occur in crowded cellular environments and interact with other proteins, nucleic acids, and organelles. Since most previous experimental protein structure determination techniques require that proteins occur in idealized, non-physiological environments, the effects of realistic cellular environments on protein structure are largely unexplored. Recently, Förster resonance energy transfer (FRET) has been shown to be an effective experimental method for investigating protein structure in vivo. Inter-residue distances measured in vivo can be incorporated as restraints in molecular dynamics (MD) simulations to model protein structural dynamics in vivo. Since most FRET studies only obtain inter-residue separations for a small number of amino acid pairs, it is important to determine the minimum number of restraints in the MD simulations that are required to achieve a given root-mean-square deviation (RMSD) from the experimental structural ensemble. Further, what is the optimal method for selecting these inter-residue restraints? Here, we implement several methods for selecting the most important FRET pairs and determine the number of pairs Nr that are needed to induce conformational changes in proteins between two experimentally determined structures. We find that enforcing only a small fraction of restraints, Nr/N 0.08, where N is the number of amino acids, can induce the conformational changes. These results establish the efficacy of FRET-assisted MD simulations for atomic scale structural modeling of proteins in vivo. © 2024, CC BY.

关键词： Conformations

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Influence of the Cooling Rate on the Solidification Path and Microstructure of a Alcocrfeni2.1

SSRN

引用

SSRN 2023年

作者： Oliveira, Pedro Henrique Fernandes Mancilha, Pedro Henrique Siqueira Reyes, Rodrigo André Valenzuela de Gouveia, Guilherme Lisboa Bolfarini, Claudemiro Spinelli, José Eduardo Coury, Francisco Gil Department of Materials Engineering Federal University of São Carlos Rod. Washington Luís Km 235 SP São CarlosCEP 13565-905 Brazil Federal University of São Carlos Graduate Program in Materials Science and Engineering Rod. Washington Luís Km 235 SP São CarlosCEP 13565-905 Brazil

The AlCoCrFeNi2.1 alloy is a promising eutectic high entropy alloy which may act as an in-situ composite, showing a trade-off between mechanical properties and ductility. Controlling the microstructure formation is crucial for achieving the best balance since it is closely related to the cooling rates during solidification. Hence, the present study determined the relationship between different cooling rates and the formed microstructures. As such, the AlCoCrFeNi2.1 alloy was subjected to a directional solidification process so that samples solidified at different cooling rates could be generated. The examined samples corresponded to a range from 1 to 6 °C/s, which resulted in microstructures composed of primary dendrites and uncoupled eutectic, with varying secondary dendritic spacings from 18 to 54 mm and eutectic spacings from 4.5 to 10 mm. . The use of CALPHAD, XRD, SEM-EDS, and EBSD phase mapping enabled to determine that the primary FCC dendrites formed in all samples enveloped by the FCC+B2 eutectic. Moreover, the solidification cooling rate affected both dendritic (primary phase) and eutectic length-scales. Finally, the solidification sequence path was able to be changed, and the primary FCC dendrites were also able to form, due to the non-equilibrium nature of the solidification process, which imposed particular segregation and growth conditions. © 2023, The Authors. All rights reserved.

关键词： Solidification

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Crystal structure-controlled synthesis of NiMoO4/NiO hierarchical microspheres for high-performance supercapacitors and photocatalysts

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Journal of Energy Storage 2024年 97卷

作者： Lee, Kuen-Chan Huang, Jen-Hsien Wu, Yen-Ju Wang, Kuan-Syun Cho, Er-Chieh Hsu, Shih-Chieh Liu, Ting-Yu Department of Science Education National Taipei University of Education No. 134 Sec. 2 Heping E. Road Da-an District Taipei City106 Taiwan Ph.D. Program in Medical Neuroscience College of Medical Science and Technology Taipei Medical University 250 Wuxing Street Taipei City110 Taiwan Department of Green Material Technology Green Technology Research Institute CPC Corporation No.2 Zuonan Rd. Nanzi District Kaohsiung City81126 Taiwan 1-2-1 Sengen Tsukuba Ibaraki305-0047 Japan Department of Materials Engineering Ming Chi University of Technology New Taipei City243303 Taiwan School of Pharmacy College of Pharmacy Taipei Medical University 250 Wuxing Street Taipei City110 Taiwan Department of Chemical and Materials Engineering Tamkang University No. 151 Yingzhuan Road Tamsui District New Taipei City25137 Taiwan Department of Chemical Engineering and Materials Science Yuan Ze University Taoyuan City32003 Taiwan College of Engineering & Center for Sustainability and Energy Technologies Chang Gung University Taoyuan33302 Taiwan

Global environmental challenges and energy crises have driven researchers to develop multifunctional and highly efficient nanomaterials. This study presents dual-functional NiMoO4 (NMO)/NiO hierarchical microspheres that can serve as supercapacitors and photocatalysts prepared using a microwave-assisted hydrothermal method. The α- and β-phase contents of NMO can be regulated by controlling the post-annealing temperature and pH value of the precursor solution. The as-prepared NMO/NiO nanocomposites exhibited dual Faradaic redox reactions attributed to NMO and NiO, leading to remarkable supercapacitor performance. In addition, the constructed heterojunction between NMO and NiO also improved charge separation, leading to excellent photocatalytic capability. Based on the results, NMO with a higher β-phase content showed better supercapacitive and photocatalytic performance owing to its higher conductivity. The optimal NMO/NiO composite displayed a specific capacitance of 943 F g−1 at 1 A/g and excellent cycling stability, with 83.1 % retention at 5 A/g after 4000 cycles. Additionally, it demonstrated an outstanding photocatalytic capability for the degradation of methylene blue (MB), achieving a rate constant of (0.0113 min−1). © 2024 Elsevier Ltd

关键词： Supercapacitor

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Terahertz Magnetospectroscopy of Gadolinium Gallium Garnet in Fields up to 25 T

Terahertz Magnetospectroscopy of Gadolinium Gallium Garnet i...

引用

JSAP-OSA Joint Symposia, JSAP 2021

作者： Bao, J. Peraca, N. Marquez Tay, F. Kritzell, T.E. Li, X. Noe, G.T. Katayama, I. Takeda, J. Nojiri, H. Yamahara, H. Tabata, H. Baydin, A. Kono, J. Department of Physics and Astronomy Rice University HoustonTX United States Department of Electrical and Computer Engineering Rice University HoustonTX United States Applied Physics Graduate Program Smalley-Curl Institute Rice University HoustonTX United States Department of Physics Graduate School of Engineering Science Yokohama National University Yokohama Japan Institute for Materials Research Tohoku University Sendai Japan Department of Electrical Engineering and Information Systems Graduate School of Engineering University of Tokyo Japan Smalley-Curl Institute Rice University HoustonTX United States Department of Materials Science and NanoEngineering Rice University HoustonTX United States

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Suppressing Chemical Corrosions of Lithium Metal Anodes

arXiv

引用

arXiv 2022年

作者： Lu, Bingyu Li, Weikang Cheng, Diyi Ceja, Miguel Bao, Wurigumula Fang, Chengcheng Meng, Ying Shirley Department of NanoEngineering University of California La Jolla San DiegoCA92093 United States Materials Science and Engineering Program University of California La Jolla San DiegoCA92093 United States Department of Chemical Engineering and Materials Science Michigan State University East LansingMI48824 United States Pritzker School of Molecular Engineering University of Chicago ChicagoIL60637 United States

The lithium (Li) metal anode is essential for next generation high energy density rechargeable Li metal batteries. Although extensive studies have been performed to prolong the cycle life of Li metal batteries, the calendar life, which associates with chemical corrosion of Li metal in liquid electrolytes, has not been quantitatively understood. Here, by combing the Titration Gas Chromatography (TGC) method and Cryogenic Focused Ion Beam (Cryo-FIB), we established a quantitative relationship between the chemical corrosion rate and electrochemically deposited Li morphology in various liquid electrolyte systems. We identified that the corrosion rate is dominated by the porosity of the deposited Li. The larger the porosity of deposited Li has, the faster the corrosion rate will be. We further proposed strategies to mitigate the chemical corrosion on Li thus to extend the calendar life of Li metal batteries. By strictly controlling the stacking pressure during Li plating, Li deposits with ultra-low porosity can be achieved, suppressing the corrosion rate to 0.08 ± 0.16%/day compared with 1.71 ± 0.19%/day of the high-porosity Li. Copyright © 2022, The Authors. All rights reserved.

关键词： Electrolytes

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Evidence for Two-Stage Hardening in an Al-Zn-Mg-Cu Alloy Processed by High-Pressure Torsion

SSRN

引用

SSRN 2022年

作者： dos Santos, Igor Cuzzuol Mazzer, Eric M. Figueiredo, Roberto B. Langdon, Terence G. Rodrigues Pereira, Pedro Henrique Graduate Program in Metallurgical Materials and Mining Engineering Universidade Federal de Minas Gerais MG Belo Horizonte31270-901 Brazil Department of Materials Science and Engineering Universidade Federal de São Carlos SP São Carlos13565-905 Brazil Department of Metallurgical and Materials Engineering Universidade Federal de Minas Gerais MG Belo Horizonte31270-901 Brazil Materials Research Group Department of Mechanical Engineering University of Southampton SouthamptonSO17 1BJ United Kingdom

Experiments were conducted to assess the effect of torsional straining on the microstructural evolution of an Al-5.7Zn-1.8Mg-2.1Cu alloy containing dispersed second phase particles prior to deformation. The results show that the material exhibits two distinct and consecutive hardening stages when processed through 1/8, 1, 5, 30, 50 and 100 turns in high-pressure torsion (HPT). There is an initial increase in the Vickers hardness from ~120 Hv in the unprocessed state to ~240 Hv after 1 turn. In this first stage, hardening occurs primarily through the accumulation and rearrangement of dislocations into fine cells/subgrains. A quasi-stationary condition is achieved with further straining where the microhardness remains nearly constant and the grain size is ~140 nm up to 30 revolutions. Thereafter, the microstructure consists of ultrafine and slightly elongated grains but the second phases are continuously fragmented. This fragmentation produces a new hardening stage and the development of a uniform array of highly elongated grains with an average size of ~93 nm after 100 HPT turns. It is shown that this two-stage hardening is consistent with conventional Hall-Petch strengthening and the development of the second stage is attributed to a reduction in grain boundary mobility due to the segregation of solutes. © 2022, The Authors. All rights reserved.

关键词： Aluminum alloys

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An Investigation of Cu/Ni/Ga Interfacial Reaction with Different Ni/Ga Ratio

An Investigation of Cu/Ni/Ga Interfacial Reaction with Diffe...

引用

International Conference on Electronics Packaging (ICEP)

作者： Tzu-hsuan Huang Jian-wei Huang Zhih-feng Lin Shih-kang Lin Program on Semiconductor Packaging and Testing Academy of Innovative Semiconductor and Sustainable Manufacturing National Cheng Kung University Tainan Taiwan Department of Materials Science and Engineering National Cheng Kung University Tainan Taiwan Hierarchical Green-Energy Materials (Hi-GEM) Research Center National Cheng Kung University Tainan Taiwan Program on Smart and Sustainable Manufacturing Academy of Innovative Semiconductor and Sustainable Manufacturing National Cheng Kung University Tainan Taiwan

ISBN: (数字)9784991191176

ISBN: (纸本)9798350385908

In this article, we utilized electroplating method forming Cu/Ni/Ga structure. Interfacial reaction was investigated with different ratio of Ni: Ga 7:3 and 1:20. The result showed that Ga reacted with the substrates immediately as plated forming NiGas and CuGa2 compound respectively in different ratio of Ni: Ga. IMCs transformed into Ni 2 Ga 3 and Cu 31.3 Ga 16.3 respectively after 300°C heat treatment. This research explored a new optimizing idea in developing Ga TLP bonding technology.

关键词： Electrochemical deposition Gallium Heat treatment Plating Nickel Compounds Bonding

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Mathematical modelling and optimization of parameters for Al-Si-Fe aluminum alloy reinforced by Al 2 O 3 and graphite particles using Taguchi method

引用

materials Today: Proceedings 2021年 44卷 979-986页

作者： Robale Dinsa Daba Devendra Kumar Sinha Habtamu Beri Satyam Shivam Gautam Gulam Mohammed Sayeed Ahmed Ram Sewak Singh Program of Mechanical Design and Manufacturing Engineering School of Mechanical Chemical and Materials Engineering ASTU ADAMA Ethiopia Department of Mechanical Engineering North Eastern Regional Institute of Science and Technology Itanagar India Department of Electronics and Communication School of Electrical Engineering and Computing ASTU ADAMA Ethiopia

In the present scenario the aluminum and its alloys are preferred due to requirement of lightweight high strength material. The present research article interrogates experimentally the study of actual density and porosity using powder metallurgy method. The experimental design is done using Taguchi L 16 orthogonal array. Actual density and porosity has been analyzed based on ‘smaller is best’ basis. Actual density and porosity are calculated using Archimedes principle. The leverage of four levels and five process parameters such as weight percentage of Al 2 O 3 , weight percentage of graphite, compaction pressure, compaction time and milling time are considered. Results reveal that Al 2 O 3 weight percentage has the highest leverage on density followed by compaction time and graphite weight percentage.

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