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Reversible Actuation of α-Borophene Nanoscrolls

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arXiv

arXiv 2023年

作者： Fabris, Guilherme S.L. Galvão, D.S. Paupitz, Ricardo Postgraduate Program in Materials Science and Engineering Federal University of Pelotas RS Pelotas96010-610 Brazil Applied Physics Department State University of Campinas SP Campinas13083-970 Brazil Sao Paulo State University - Unesp Physics Department SP Rio ClaroCEP-13506-900 Brazil

In this work, we proposed and investigated the structural and electronic properties of boron-based nanoscrolls (armchair and zigzag) using the DFTB+ method. We also investigated the electroactuation process (injecting and removing charges). A giant electroactuation was observed, but the results show relevant differences between the borophene and carbon nanoscrolls. The molecular dynamics simulations showed that the scrolls are thermally and structurally stable for a large range of temperatures (up to 600K) and the electroactuation process can be easily tuned and can be entirely reversible for some configurations. © 2023, CC BY.

关键词： Molecular dynamics

Modelling and Application of Jutes Fiber Reinforced Epoxy Composite in the Development of Wind Blade for Low Intensity Winds

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SSRN 2023年

作者： Junio, Raí Felipe Pereira Cardoso, Robson Luis B. Ramos, Roberto Paulo B. Leão Filha, Elza M. Ribeiro, Mauricio M. Candido, Verônica S. Rodrigues, Jean da S. Silva, Douglas Santos Monteiro, Sergio N. Fujiyama, Roberto T. Federal University of Pará—UFPA Engineering of Natural Resources of the Amazon Program Rua Augusto Corrêa 01 PA BelémCEP 66075-110 Brazil Federal Institute of Education Science and Technology of Pará – IFPA Materials Engineering Program Avenida Almirante Barroso 1155 Marco PA BelémCEP 66093-020 Brazil Federal University of Pará - UFPA Postgraduate Program in Industrial Engineering Rua Augusto Corrêa 01 PA BelémCEP 66075-110 Brazil Federal Institute of Education Science and Technology of Pará – IFPA Estrada do Icuí Guajará PA AnanindeuaCEP 67125-000 Brazil Military Institute of Engineering – IME Department of Materials Science Praça General Tibúrcio 80 Praia Vermelha Urca RJ Rio de JaneiroCEP 22290-270 Brazil

Natural fibres show an increasing potential as reinforcement of polymeric composites, representing a promising concurrent to glass and carbon fibres extensively used in the construction of wind turbine blades synthetic fibres recyclability/disposability and high production energy cost have already been discussed in the main turbine producing centres. In particular, the development of wind turbines for low wind speed areas can increase the energy generation potential of regions not originally eligible for the installation of large turbines. This study proposes the evaluation of the use of jute fibre (Corchorus capsularis) reinforced epoxy composite in the construction of S1210 airfoil profile, of a small-scale wind turbine for low wind speed regions, considering the structural parameters, developed incorporating the Classical Laminate Theory (CLT) and Extended Bredt-Batho Shear Flow Theory (EBSFT).In order to raise the elastic properties and enable the use of the failure criteria, the composite blades were characterized according to ASTM standards. The mechanical properties surveyed, together with the elastic parameters of the cross section, torsional stiffness, axial stiffness and flexural rigidity, demonstrated the feasibility of using the jute fiber reinforced epoxy composite in the blade construction, evaluated according to the maximum tension failure criterion. © 2023, The Authors. All rights reserved.

关键词： Laminated composites

Theoretical insights into the chemical bonding, electronic structure, and spectroscopic properties of the lanarkite Pb2SO5 structure

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arXiv

arXiv 2023年

作者： Fabris, Guilherme S.L. Ferrer, Mateus M. Sambrano, Julio R. Almeida, Cláudio R.R. Paskocimas, Carlos A. La Porta, Felipe A. Graduate Program in Materials Science and Engineering Technological Development Center Universidade Federal de Pelotas RS Pelotas96010-610 Brazil Modeling and Molecular Simulation Group São Paulo State University Bauru São Paulo17033-360 Brazil Department of Materials Engineering Federal University of Rio Grande do Norte RN Natal59078-970 Brazil Postgraduate Program in Science and Engineering of Materials Federal University of Rio Grande do Norte RN Natal59078-970 Brazil Federal University of Technology - Paraná Nanotechnology and Computational Chemistry Laboratory Avenida dos Pioneiros 3131 CEP PR Londrina86036-370 Brazil State University of Londrina Post-Graduation Program in Chemistry Rodovia Celso Garcia Cid 445 km 380 CEP PR Londrina86057-970 Brazil

Lanarkite is a mineral formed by a combination of lead, sulphur, and oxygen atoms arranged in the general chemical formula Pb2SO5 (PSO) that crystallises with monoclinic symmetry (belonging to the C2/m space group, No. 12). This mineral was first discovered in Lanarkshire, Scotland and was named after its location. PSO has a unique structure comprising alternating penta-coordinated lead [PbO5] and tetra-coordinated sulphur [SO4] clusters. This lanarkite-type structure has recently attracted significant scientific interest and has been the focus of the superconducting material research community. However, its chemistry needs to be explored further. This article presents a comprehensive investigation on the chemical bonding, electronic structure, and spectroscopic properties of the lanarkite-type PSO structure from a computational perspective. Thus, different functionals in the DFT (e.g., PBE, PBE0, PBESOL, PBESOL0, BLYP, WC1LYP37, and B3LYP) were assessed to accurately predict their fundamental properties. All the DFT calculations were performed using a triple-zeta valence plus polarisation basis set. Among all the DFT functionals tested in this study, PBE showed the best agreement with the experimental data available in the literature. Our results also reveal that the [PbO5] clusters are formed with three Pb–O bond lengths, with values of about 2.32, 2.59, and 2.84 Å, respectively, while the [SO4] clusters have the same S–O bond length of 1.57 Å. We performed a complete topological analysis of this system to comprehend these structural differences. Additionally, the PSO structure has an indirect band gap energy of 2.9 eV and an effective mass ratio (mℎ∗ /me∗) of about 0.415 (using PBE calculations) which may, in principle, indicate a low recombination of electron-hole pairs in the lanarkite structure. Therefore, we believe that a detailed understanding of their electronic structures, spectroscopic properties as well as their chemical bonding is critically important

关键词： Lead compounds

Flash Sintering with Concurrent Crystallization of Li 1.5Al 0.5Ge 1.5(PO 4) 3 Glass

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SSRN 2022年

作者： Campos, João V. Lavagnini, Isabela Reis Zallocco, Vinicius Martins Ferreira, Eduardo B. de Jesus Agnolon Pallone, Eliria Maria Rodrigues, Ana Candida Martins Graduate Program in Materials Science and Engineering Federal University of São Carlos SP São Carlos13635-905 Brazil Department of Materials Engineering Federal University of São Carlos SP São Carlos13635-905 Brazil Center for Research Technology and Education of Vitreous Materials CeRTEV FAPESP LaMaV DEMa/UFSCar SP São Carlos13635-905 Brazil Department of Biosystem Engineering University of São Paulo USP Av. Duque de Caxias Norte 225 SP Pirassununga13635-900 Brazil Postgraduate Programme in Materials Science and Engineering University of São Paulo USP FZEA Av. Duque de Caxias Norte 225 Pirassununga13635-900 Brazil Department of Materials Engineering São Carlos School of Engineering University of São Paulo USP SP São Carlos13566-590 Brazil

Single-phased Li1.5Al0.5Ge1.5(PO4)3NaSICON (Na superionic conductor) glass-ceramic is obtained via a new route using flash-sinter crystallization . Green pellets of glass powder are sinter-crystallized in a few seconds. Our results suggest that controlling the current rise during the flash event is needed to avoid overheating that could cause the melting of the samples. A processing map for the flash sinter-crystallization of Li1.5Al0.5Ge1.5(PO4)3 is developed and presented based on the current density and holding time at the steady-state. The samples fabricated by flash sinter-crystallization are compared with conventionally heated ones. Using this novel technique, single-phase glass-ceramics were obtained with total ionic conductivity at room temperature surpassing those prepared by conventional heating (2.26 10-4S cm-1 and 1.36 10-4S cm-1, respectively). © 2022, The Authors. All rights reserved.

关键词： Solid electrolytes

Eco-Friendly High Entropy Oxide Rock-Salt Type Structure for Oxygen Evolution Reaction Obtained by Green Synthesis Using Red Seaweed (Rhodophyta)

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SSRN 2024年

作者： Santos, Jakeline RAIANE DORA DOS Raimundo, Rafael A. de Oliveira, João F.G.A. Hortencio, Johnnys da S. Loureiro, Francisco J.A. Macedo, Daniel A. Morales, Marco A. Gualandi, Isacco Tonelli, Domenica Gomes, Uílame U. Materials Science and Engineering Postgraduate Program UFRN Natal59078-970 Brazil Department of Industrial Chemistry "Toso Montanari" Industrial Chemistry UNIBO V.le Risorgimento 4 Bologna40136 Italy Department of Theoretical and Experimental Physics Federal University of Rio Grande do Norte UFRN Natal59078-970 Brazil Gleb Wataghin Institute of Physics - R. Sérgio Buarque de Holanda 777 - Cidade Universitária Campinas13083-859 Brazil Department of Chemistry Federal University of Paraíba UFPB João Pessoa58.051-900 Brazil TEMA - Centre for Mechanical Technology and Automation Mechanical Engineering Department University of Aveiro 3810-193 Portugal LASI - Intelligent Systems Associate Laboratory Portugal Materials Science and Engineering Postgraduate Program Federal University of Paraíba UFPB João Pessoa58051-900 Brazil

Global energy consumption increases year after year, causing the depletion of non-renewable sources. According to the International Energy Agency (IEA), global demand for electrical energy is expected to increase by 3.3% in 2024. Therefore, developing new renewable sources is urgent, including new devices for energy storage and conversion, particularly those governed by electrochemical reactions. Water splitting is a clean and sustainable technology capable of facing this issue by producing oxygen and hydrogen from water and electricity. However, a problem related to this technology is the slow kinetics, making it necessary to develop new electrocatalysts with high electrochemical performance. To meet this requirement, this work deals with for the first time a high entropy oxide with rock-salt structure synthesized by a green solgel synthesis using red seaweed (Rhodophyta) as polymerizing agent. Solgel synthesis allows the large-scale production of nanomaterials with high uniformity and dispersion of the chemical elements involved. The literature, which discussed the production of these oxides, reveals that agents harmful to the environment are applied during the synthesis steps, including sodium hydroxide, acetic acid, hexadecyltrimethylammonium bromide, urea, and ammonia. The composition of the high entropy oxide is (Mg0.2 Ni0.2 Co0.2 Cu0.2 Zn0.2 )O, it displays a low overpotential (336 mV vs. RHE at 10 mA cm-2 ), Tafel slope of 68 mV dec-1 , and excellent durability. The electrochemical performance of the high entropy oxide prepared in this work is superior to other electrocatalysts of the same class that were produced using transition metal-based precursors. © 2024, The Authors. All rights reserved.

关键词： Entropy

Estimation of the main air pollutants from different biomasses under combustion atmospheres by artificial neural networks

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Chemosphere 2024年 352卷 141484页

作者： Monteiro, Thalyssa Oliveira Alves, Pedro Augusto Araújo da Silva de Almeida Nava Barradas Filho, Alex Oliveira Villa-Vélez, Harvey Alexander Cruz, Glauber Postgraduate Program in Mechanical Engineering (PPGMEC) Department of Mechanics and Materials Federal Institute of Education Science and Technology of Maranhão (IFMA) Maranhão São Luís Brazil Postgraduate Program in Computer Science and Computational Mathematics (PPG-CCMC) Department of Computer Science University of São Paulo (USP) São Carlos São Paulo Brazil Data Analysis and Artificial Intelligence Laboratory (DARTi) Department of Computational Engineering Federal University of Maranhão (UFMA) Maranhão São Luís Brazil Department of Chemical Engineering Federal University of Maranhão (UFMA) Maranhão São Luís Brazil Processes and Thermal Systems Laboratory (LPSisTer) Department of Mechanical Engineering Federal University of Maranhão (UFMA) Maranhão São Luís Brazil

The production of biofuels to be used as bioenergy under combustion processes generates some gaseous emissions (CO, CO2, NOx, SOx, and other pollutants), affecting living organisms and requiring careful assessments. H... 详细信息

The production of biofuels to be used as bioenergy under combustion processes generates some gaseous emissions (CO, CO₂, NO_x, SO_x, and other pollutants), affecting living organisms and requiring careful assessments. However, obtaining such information experimentally for data evaluation is costly and time-consuming and its in situ obtaining for regional biomasses (e.g., those from Northeast Brazil (NEB) is still a major challenge. This paper reports on the application of artificial neural networks (ANNs) for the prediction of the main air pollutants (CO, CO₂, NO, and SO₂) produced during the direct biomass combustion (N₂/O₂:80/20%) with the use of ultimate analysis (carbon, hydrogen, nitrogen, sulfur, and oxygen). 116 worldwide biomasses were used as input data, which is a relevant alternative to overcome the lack of experimental resources in NEB and obtain such information. Cross-validation was conducted with k-fold to optimize the ANNs and performance was analyzed with the use of statistical errors for accuracy assessments. The results showed an acceptable statistical performance for all architectures of ANNs, with 0.001–12.41% MAPE, 0.001–5.82 mg Nm⁻³ MAE, and 0.03–52.30 mg Nm⁻³ RMSE, highlighting the high precision of the emissions studied. On average, the differences between predicted and real values for CO, CO₂, NO, and SO₂ emissions from NEB biomasses were approximately 0.01%, 10⁻⁶%, 0.14%, and 0.05%, respectively. Pearson coefficient provided consistent results of concentration of the ultimate analysis in relation to the emissions studied and effectiveness of the test set in the developed models. © 2024 Elsevier Ltd

关键词： Brazilian northeastern Environmental statistics Evaluation metrics Gaseous emissions Predictive models Thermoconversion

X-Ray Induced Degradation During Xps Analysis of Dicarboxylic Acid Powders

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SSRN 2023年

作者： Ferreira, José Mario Trindade, Gustavo F. Simonelli, George de Moraes Pires, Carlos Augusto Da Silva, Ana Cristina Morais Rossi, Jesualdo Luiz dos Santos, Luiz Carlos Lobato Johnson, Patrick Alfred Department of Materials Science and Engineering Iowa State University AmesIA50011 United States Faculty of Engineering and Physical Sciences University of Surrey SurreyGU2 7XH United Kingdom National Physical Laboratory Middlesex TeddingtonTW11 0LW United Kingdom Chemical Engineering Postgraduate Program Federal University of Bahia 40210-630 Brazil Nuclear and Energy Research Institute - IPEN São Paulo05508-000 Brazil University of Wyoming United States

It is widely recognized that exposure to X-rays during XPS analysis can decompose different materials, resulting in mass loss and changes in chemical composition. These effects are evident in the near-edge X-ray absorption structure spectra of dicarboxylic acid powders, posing a fundamental limit to sensitivity for surface chemical analysis. Understanding the chemistry and kinetics of radiation decomposition is necessary for the accuracy and validation of XPS analysis on dicarboxylic acids. Here we evaluate the impact of X-ray exposure on characterizing chemical changes in three different dicarboxylic acids with varying aliphatic carbon chain lengths. From this investigation we propose straightforward correlations relating the tendency for radiation-induced decomposition based on the chemical structure of the acids. We employed two types of spectra, those acquired with minimal interaction (snapshot) and high-resolution spectra obtained over an extended period, to show that normal analysis conditions are likely to degrade these type of materials. © 2023, The Authors. All rights reserved.

关键词： X ray photoelectron spectroscopy

Phase and crystallite size analysis of (Ti1-xMox)C-(Ni,Cr) cermet obtained by mechanical alloying

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AIP Conference Proceedings 2018年第1期1945卷

作者： Suryana Muhammad Anis Azwar Manaf 1Materials Science Postgraduate Program Physics Department Universitas Indonesia Jl. Salemba Raya No.4 Jakarta 10430 Indonesia 2Department of Metallurgy and Materials Engineering Universitas Indonesia Depok 16424 Indonesia

In this paper, we report the phase and crystallite size analysis of (Ti1-xMox)C-(Ni,Cr) with x = 0-0.5 cermet obtained by mechanical alloying of Ti, Mo, Ni, Cr and C elemental powders using a high-energy shaker ball mill under wet condition for 10 hours. The process used toluene as process control agent and the ball to mass ratio was 10:1. The mechanically milled powder was then consolidated and subsequently heated at a temperature 850°C for 2 hours under an argon flow to prevent oxidation. The product was characterized by X-ray diffraction (XRD) and scanning electron microscope equipped with energy dispersive analyzer. Results shown that, by the selection of appropriate condition during the mechanical alloying process, a metastable Ti-Ni-Cr-C powders could be obtained. The powder then allowed the in situ synthesis of TiC-(Ni,Cr) cermet which took place during exposure time at a high temperature that applied in reactive sintering step. Addition to molybdenum has caused shifting the TiC XRD peaks to a slightly higher angle which indicated that molybdenum dissolved in TiC phase. The crystallite size distribution of TiC is discussed in the report, which showing that the mean size decreased with the addition of molybdenum.

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Investigation of a novel biocide material for biocorrosion in simulated seawater: A case study on Tinospora cordifolia extract

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Case Studies in Chemical and Environmental engineering 2024年 10卷

作者： Royani, Ahmad Hanafi, Muhammad Aigbodion, Victor Sunday Prastya, Muhammad Eka Verma, Chandrabhan Mubarak, Nabisab Mujawar Alfantazi, Akram Manaf, Azwar Research Center for Metallurgy National Research and Innovation Agency – BRIN Kawasan Puspiptek Banten Tangerang Selatan 15314 Indonesia Postgraduate Program of Materials Science Study Department of Physics Faculty of Mathematics and Natural Sciences Universitas Indonesia Depok 16424 Indonesia Research Center for Pharmaceutical Ingredients and Traditional Medicine National Research and Innovation Agency – BRIN Kawasan Puspiptek Banten Tangerang Selatan 15314 Indonesia Department of Metallurgical and Materials Engineering University of Nigeria Nsukka 410001 Nigeria Department of Chemical and Petroleum Engineering Khalifa University of Science and Technology P.O. Box 127788 Abu Dhabi United Arab Emirates Petroleum and Chemical Engineering Faculty of Engineering Universiti Teknologi Brunei Bandar Seri Begawan BE1410 Brunei Darussalam Department of Biosciences Saveetha School of Engineering Saveetha Institute of Medical and Technical Sciences Chennai India

This case report investigates the preventive effect of Tinospora cordifolia extract on biocorrosion induced by Pseudomonas aeruginosa on mild steel API 5L in the simulated seawater medium. Electrochemical techniques, spectroscopic techniques, and surface analysis were employed to investigate biocide performance and corrosion behavior. P. aeruginosa has been shown to enhance iron dissolution in seawater medium. These findings point to the role of P. aeruginosa bacteria in forming differential oxygen, which causes corrosion. Morphology results from atomic Fourier microscopy (AFM) highlight the presence of P. aeruginosa in biotic environments, where the surface is rougher than in abiotic conditions. On the other hand, adding T. cordifolia to the biotic medium resulted in a smoother and more homogeneous surface without any significant deterioration. Electrochemical findings reveal that adding 300 mg L⁻¹ of T. cordifolia extract prevents the microbiologically influenced corrosion (MIC) of steel API 5L, with an optimum effectiveness value of 74.50 % after 21 days of incubation. This protective effect is caused by forming a more compact iron oxide surface layer and the adsorption of phenolic active compounds such as Moupinamide and others on the surface of mild steel API 5L, as detected by liquid chromatography-mass/spectrometry-mass spectrometry (LCMS-MS), Fourier-transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FE-SEM) techniques. © 2024 The Authors

关键词： Bio-corrosion Biofilm Green biocide Plant extract Pseudomonas aeruginosa Tinospora cordifolia