检索结果-内蒙古大学图书馆

Influence of Al-5.0Nb-0.5B inoculant on the microstructure and mechanical properties of AA 2017 alloy fabricated using laser-based powder bed fusion

引用

Journal of Alloys and Compounds 2025年 1032卷

作者： dos Santos Bomfim, Pamela Karina Batistão, Bruna Fernanda de Araújo, Aylanna Priscila Marques Pereira, Leandro Henrique Buzolin, Ricardo Henrique Amancio-Filho, Sergio T. Afonso, Conrado Ramos Moreira Bolfarini, Claudemiro Kiminami, Claudio Shyinti Coury, Francisco Gil Gargarella, Piter Graduate Program in Materials Science and Engineering Federal University of São Carlos Rod.Washington Luis Km 235 SP São Carlos13565-905 Brazil High Performance and Lightweight Materials Group kopernikusgasse 24 Graz8010 Austria BMK Endowed Professorship for Aviation Kopernikusgasse 24 Graz8010 Austria Institute of Materials Science Joining and Forming Graz University of Technology Kopernikugasse 24/l Graz80210 Austria Rod. Washington Luiz km 235 São Carlos13565-905 Brazil Center of Characterization and Development of Materials Federal University of São Carlos Rod. Washington Luiz km 235 SP-310 SP São Carlos13565-905 Brazil

This study investigated the influence of the inoculant Al-5.0Nb-0.5B on the microstructure and mechanical properties of the AA 2017 alloy fabricated using laser-based powder bed fusion (L-PBF). The AA 2017 alloy powder was obtained through gas atomization and then mixed with 2 wt% of Al-5.0Nb-0.5B powder (20–53 µm) and synthesized using the L-PBF technique. The small addition of the Al-5.0Nb-0.5B, coupled with specific processing parameters, led to a reduction in the fraction of cracks and transformed the solidification structure from cellular to equiaxial. Additionally, it resulted in a grain size reduction down to 4.0 ± 2.9 µm and a low fiber texture. Due to the refined grains, the AA 2017 samples with 2 wt% Al-5.0Nb-0.5B exhibited a high yield strength of 215 ± 33 MPa and ultimate compressive strength of 602 ± 47 MPa, compared to the AA 2017 alloy samples, which exhibited yield strength of 171 ± 8 MPa and ultimate compressive strength of 427 ± 46 MPa. The addition of a small fraction of Al-5.0Nb-0.5B to the AA 2017 alloy, produced by L-PBF, is a promising alternative for manufacturing lightweight parts with a lower amount of hot cracks and equiaxial microstructure. The results show that the use of inoculant with the micrometric size is an effective alternative to the use of nanoparticles, which has a higher safety risk, is usually difficult to homogenize and may promote agglomeration. © 2025 Elsevier B.V.

关键词： Compressive strength

来源：评论

学校读者我要写书评

暂无评论

Picosecond optical-to-x-ray (Cd,Mg)Te radiation detectors

Picosecond optical-to-x-ray (Cd,Mg)Te radiation detectors

引用

Conference on Lasers and Electro-Optics (CLEO)

作者： J. Cheng I. Komissarov G. Chen D. Chakraborty S. Kutcher H. Chen S. Trivedi Roman Sobolewski Materials Science Graduate Program University of Rochester Rochester New York USA Laboratory for Laser Energetics University of Rochester Rochester New York USA Department of Electrical and Computer Engineering University of Rochester Rochester New York USA Brimrose Technology Corp Sparks Maryland USA

We developed a dual optical/x-ray ultrafast photodetector based on in-house grown Cd 0.97 Mg 0.03 Te single crystals. The detector is characterized by ~200 ps full-width-at-half-maximum, readout-electronics limited p... 详细信息

ISBN: (纸本)9781957171258

关键词： Femtosecond lasers Photodetectors Photon counting Pump probe spectroscopy Radiation detectors Ti:sapphire lasers

来源：评论

学校读者我要写书评

暂无评论

Microwave Synthesis of Nanostructured High Entropy Spinel

SSRN

引用

SSRN 2022年

作者： Gunnewiek, Rodolfo Foster Klein Cardoso, André L.F. Perdomo, Claudia P.F. Foschiani, Beatriz G. Xaraba, Julia A. Zabotto, Fabio L. Federal University of Sao Carlos Graduate Program in Materials Science and Engineering SP Sao Carlos Brazil Federal University of Sao Carlos Department of Materials Engineering SP São Carlos Brazil Federal University of Sao Carlos Department of Physics SP São Carlos Brazil

A single-phase cubic high entropy spinel (HES) (CoCrFeMnNi)3O4 was microwave synthesized by a polymer-based method. The complete microwave-synthesis took no longer than 2 hours. The HEŚs were characterized by X-ray diffractometry (XRD), transmission electron microscopy (TEM) and diffuse reflectance spectroscopy (DRS). After calcination of 800 and 900 °C, the powders showed nanostructured cubic single-phases. The band gap energy (Eg) of the microwave irradiated HES was 2.2 eV compared to the 2.45 eV of the conventionally calcined. These Eg values indicate application possibilities in the field of catalytic reforming of carbon dioxide as a promising catalyst with tunable properties. © 2022, The Authors. All rights reserved.

关键词： Entropy

来源：评论

学校读者我要写书评

暂无评论

Coherent Acoustic Phonons in Bi2Se3 Ultrathin Films Probed by Femtosecond, Optical Pump-Probe Spectroscopy

Coherent Acoustic Phonons in Bi2Se3 Ultrathin Films Probed b...

引用

CLEO: Fundamental science, CLEO:FS 2024 - Part of Conference on Lasers and Electro-Optics, CLEO 2024

作者： Cheng, Jing Niherysh, Kiryl A. Francis, Peter Chakraborty, Debamitra Lombardi, Floriana Erts, Donats Prischepa, Serghej L. Laszcz, Adam Komissarov, Ivan V. Sobolewski, Roman Materials Science Graduate Program University of Rochester RochesterNY14627 United States Laboratory for Laser Energetics University of Rochester RochesterNY14623-1299 United States Department of Microtechnology and Nanoscience Chalmers University of Technology Gothenburg Sweden Institute of Chemical Physics University of Latvia Riga Latvia Department of Electrical and Computer Engineering University of Rochester RochesterNY14627 United States Dipartimento di Fisica "E.R. Caianiello" Università degli Studi di Salerno Sa FiscianoI-84084 Italy Lukasiewicz Research Network Institute of Microelectronics and Photonics WarszawaPL-02668 Poland

ISBN: (纸本)9781957171395

The dynamics of coherent acoustic phonons in the Bi2Se3 layered crystal system are investigated. The findings reveal that the frequency evolution of breathing modes with the number of the material quintuple layers and the dispersion relation both can be explained by a modified chain model with a nonuniform coupling force. © Optica Publishing Group 2024, © 2024 The Author(s)

关键词： Ultrathin films

来源：评论

学校读者我要写书评

暂无评论

Machine-learned molecular surface and its application to implicit solvent simulations

arXiv

引用

arXiv 2021年

作者： Wei, Haixin Zhao, Zekai Luo, Ray Departments of Materials Science and Engineering Molecular Biology and Biochemistry Chemical and Biomolecular Engineering and Biomedical Engineering Graduate Program in Chemical and Materials Physics University of California IrvineCA92697 United States

Implicit solvent models, such as Poisson-Boltzmann models, play important roles in computational studies of biomolecules. A vital step in almost all implicit solvent models is to determine the solvent-solute interface, and the solvent excluded surface (SES) is the most widely used interface definition in these models. However, classical algorithms used for computing SES are geometry-based, thus neither suitable for parallel implementations nor convenient for obtaining surface derivatives. To address the limitations, we explored a machine learning strategy to obtain a level-set formulation for the SES. The training process was conducted in three steps, eventually leading to a model with over 95% agreement with the classical SES. Visualization of tested molecular surfaces shows that the machine-learned SES overlaps with the classical SES on almost all situations. We also implemented the machine-learned SES into the Amber/PBSA program to study its performance on reaction field energy calculation. The analysis shows that the two sets of reaction field energies are highly consistent with 1% deviation on average. Given its level-set formulation, we expect the machine-learned SES to be applied in molecular simulations that require either surface derivatives or high efficiency on parallel computing platforms. © 2021, CC BY.

关键词： Solvents

来源：评论

学校读者我要写书评

暂无评论

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

arXiv

引用

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

来源：评论

学校读者我要写书评

暂无评论

Interaction between Nanofibrillated Cellulose (Nfc) and Portland Cement Mortars Subjected to Alkali-Aggregate Reaction (Aar)

SSRN

引用

SSRN 2024年

作者： Farias, Marcelo Miranda Pereira, Eduardo de Melo Carvalho, Benjamim Goncalves, Jose de Medeiros, Marcelo Henrique Farias Graduate Program in Materials Science and Engineering State University of Ponta Grossa Avenida Carlos Cavalcanti 4748 Uvaranas Ponta GrossaCEP: 84030-900 Brazil Department of Civil and Environmental Engineering The University of Alberta EdmontonABT6G 1H9 Canada Department of Civil Construction – Polytechnical Center Paraná CuritibaCEP: 81.530-000 Brazil

HIGHLIGHTS• NFC can increase the compressive strength of cement pastes by up to 59%.• NFC degrades in the pore solution of mortars after 60 days of curing;• NFC degradation reduces the tensile strength of cement pastes and mortars;• NFC can mitigate the effects of alkali-aggregate reaction in mortars;• NFC fibers act as a "stress reserve" in expansive mechanisms caused by AAR. © 2024, The Authors. All rights reserved.

关键词： Mortar

来源：评论

学校读者我要写书评

暂无评论

Effect of Fe on the Photo/Piezocatalytic Activity of Bazr1-2xfe2xo3-Δ Ceramics

SSRN

引用

SSRN 2023年

作者： Fernandes, Daiane Hernandes, Paola Gay Moreira, Mario Lucio Raubach, Cristiane Wienke Jardim, Pedro Lovato Gomes Ferrer, Mateus Meneghetti Moreira, Eduardo Ceretta Mastelaro, Valmor Roberto Cava, Sergio da S. Post-Graduate Program in Materials Science and Engineering Federal University of Pelotas RS Pelotas96010-610 Brazil Post-Graduate Program in Physics Federal University of Pelotas RS Capão do Leão96160-000 Brazil Spectroscopy Laboratory Federal University of Pampa RS Bagé96413-172 Brazil Physics Institute São Paulo University SP São Carlos13560-970 Brazil

BaZr1-2xFe2xO3-δ (x=0.00, 0.02, 0.04 and 0.08) samples were prepared by microwave-assisted hydrothermal method quickly and at low-temperature. Furthermore, we explored for the first time the effect of iron (Fe) in the barium zirconate (BZO) lattice on photocatalytic and piezocatalytic activity to degrade organic dye. Fe insertion reduced the band gap, altered the electronic structure and induced luminescence quenching. The catalytic activity of the samples was analyzed through the degradation of the rhodamine B (RhB) dye. The photocatalytic experiment was performed under UVC light and the piezocatalytic experiment under ultrasonic vibration. The pure sample of BZO showed better photocatalytic performance, while the insertion of Fe was unfavorable to degrade RhB. In contrast, pure BZO has negligible piezocatalytic activity, but a low Fe content is highly beneficial for promoting piezocatalysis. Based on the findings, this study provides important information for obtaining effective photocatalysts and piezocatalysts to be used in environmental remediation. © 2023, The Authors. All rights reserved.

关键词： Iron

来源：评论

学校读者我要写书评

暂无评论

Transferable screened range-separated hybrid functionals for electronic and optical properties of van der Waals materials

arXiv

引用

arXiv 2023年

作者： Camarasa-Gómez, María Ramasubramaniam, Ashwin Neaton, Jeffrey B. Kronik, Leeor Department of Molecular Chemistry and Materials Science Weizmann Institute of Science Rehovoth7610001 Israel Department of Mechanical and Industrial Engineering University of Massachusetts Amherst AmherstMA01003 United States Materials Science and Engineering Graduate Program University of Massachusetts Amherst AmherstMA01003 United States Department of Physics University of California BerkeleyCA94720 United States Materials Sciences Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Kavli Energy NanoSciences Institute at Berkeley University of California BerkeleyCA94720 United States

The accurate description of electronic properties and optical absorption spectra is a long-standing challenge for density functional theory. Recently, the introduction of screened range-separated hybrid (SRSH) functionals for solid-state materials has allowed for the calculation of fundamental band gaps and optical absorption spectra that are in very good agreement with many-body perturbation theory. However, since solid-state SRSH functionals are typically tuned to reproduce the properties of bulk phases, their transferability to low-dimensional structures, which experience substantially different screening than in the bulk, remains an open question. In this work, we explore the transferability of SRSH functionals to several prototypical van der Waals materials, including transition-metal sulfides and selenides, indium selenide, black phosphorus, and hexagonal boron nitride. Considering the bulk and a monolayer of these materials as limiting cases, we show that the parameters of the SRSH functional can be determined systematically, using only the band-edge quasiparticle energies of these extremal structural phases as fitting targets. The resulting SRSH functionals can describe both electronic bandstructures and optical absorption spectra with accuracy comparable to more demanding ab initio many-body perturbation theory (GW and Bethe-Salpeter equation) approaches. Selected examples also demonstrate that the SRSH parameters, obtained from the bulk and monolayer reference structures, display good accuracy for bandstructures and optical spectra of bilayers, indicating a degree of transferability that is independent of the fitting procedure. Copyright © 2023, The Authors. All rights reserved.

关键词： Transition metals

来源：评论

学校读者我要写书评

暂无评论

Effect of Fe on the Photo/Piezocatalytic Activity of Bazr1-2xfe2xo3-Δ Ceramics

SSRN

引用

SSRN 2023年

作者： Fernandes, Daiane Hernandes, Paola Gay Moreira, Mario Lucio Raubach, Cristiane Wienke Gomes Jardim, Pedro Lovato Ferrer, Mateus Meneghetti Moreira, Eduardo Ceretta Mastelaro, Valmor Roberto Cava, Sergio da S. Post-Graduate Program in Materials Science and Engineering Federal University of Pelotas RS Pelotas96010-610 Brazil Post-Graduate Program in Physics Federal University of Pelotas RS Capão do Leão96160-000 Brazil Spectroscopy Laboratory Federal University of Pampa RS Bagé96413-172 Brazil Physics Institute São Paulo University SP São Carlos13560-970 Brazil

关键词： Temperature

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：