Structural Coupling
Mostrando 1-12 de 290 artigos, teses e dissertações.
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1. Finite element computational development for thermo-mechanical analysis of plane steel structures exposed to fire
Abstract This article presents a numerical formulation based on finite element procedures for application in nonlinear thermo-mechanical analyses of steel planar structures under fire condition. The mechanical properties of structural elements degrade when subjected to high temperatures, resulting in significant reductions in strength and stiffness. Under th
REM - International Engineering Journal. Publicado em: 2022
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2. PMMA-SiO2 Organic-Inorganic Hybrid Coating Application to Ti-6Al-4V Alloy Prepared through the Sol-Gel Method
Siloxane-poly(methyl methacrylate) (PMMA) hybrid was synthesized based on the sol-gel method and applied to Ti-6Al-4V through dip-coating. The structural feature of the hybrid was subjected to Fourier-transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TG); its morphological properties were analyzed through scanning electron microscope (SE
J. Braz. Chem. Soc.. Publicado em: 2020-02
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3. Modular modeling approach for FDM printed structures and piezo disks for metamaterial design
Abstract Research in metamaterials has recently gained interest in the field of noise and vibration control. The ability of creating band gap zones with minimum added mass is the main feature behind its success. In addition, the use of 3D printed parts, particularly the Fused Deposition Modeling (FDM), offers a practical solution for manufacturing parts with
Lat. Am. j. solids struct.. Publicado em: 12/08/2019
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4. Structural, Morphological and Magnetic Properties of FeCo-(Fe,Co)3O4 Nanocomposite Synthesized by Proteic Sol-Gel Method Using a Rotary Oven
FeCo nanoparticles coated with (Fe,Co)3O4 (magnetite doped with cobalt) were synthesized by the proteic sol-gel chemical route. The synthesized materials were characterized by Thermogravimetry (TG), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), vibrating-sample magnetometer (VSM) and Mössbauer spectrosc
Mat. Res.. Publicado em: 18/03/2019
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5. Neolignans isolated from twigs of Nectandra leucantha Ness & Mart (Lauraceae) displayed in vitro antileishmanial activity
Abstract Background: The therapeutic arsenal for the treatment of Leishmaniasis is limited and includes toxic compounds (antimonials, amphotericin B, pentamidine and miltefosine). Given these aspects, the search for new compounds based on floristic biodiversity is crucial. In the present work, we report the isolation, characterization and antileishmanial ac
J. Venom. Anim. Toxins incl. Trop. Dis. Publicado em: 18/10/2018
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6. Computer-Guided Total Synthesis of Natural Products. Recent Examples and Future Perspectives
Quantum chemical calculations of nuclear magnetic resonance (NMR) shifts and coupling constants have been extensively employed in recent years mainly to facilitate structural elucidation of organic molecules. When the results of such calculations are used to determine the most likely structure of a natural product in advance, guiding the subsequent synthetic
J. Braz. Chem. Soc.. Publicado em: 2018-05
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7. Gamma radiation effect on sisal / polyurethane composites without coupling agents
Abstract Natural fibers and polyurethane based composites may present chemical bonding between the components of the polymer and the lignin of the fiber. The incidence of radiation can cause degradation of the polymeric material and alter its mechanical properties. The objective of this study was to obtain and characterize cold pressed composites from polyur
Polímeros. Publicado em: 29/06/2017
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8. Thermal Distortion Analysis of Inflatable Antenna Structures Considering Inflation Gas
ABSTRACT This paper addresses the static distortion and stress analysis of inflatable antenna structures subjected to a thermal load, which is a very important type of load experienced by such structures during service in orbit. Non-linear finite element analysis methods for inflatable structures were formulized, and the thermal stress of thin films was cons
J. Aerosp. Technol. Manag.. Publicado em: 2016-12
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9. Synthesis and applications of polystyrene-block-poly(N-vinyl-2-pyrrolidone) copolymers
Abstract This work describes the synthesis and applications of amphiphilic polystyrene-block-poly(N-vinyl-2-pyrrolidone) (PS-b-PVP) copolymers as a silver and silica nanoparticle surface modification agent. The synthesis of PS-b-PVP was carried out using controlled/living radical polymerization techniques. The synthesis of the block copolymers was confirmed
Polímeros. Publicado em: 15/03/2016
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10. Effect of Tetraethoxy-silane (TEOS) Amounts on the Corrosion Prevention Properties of Siloxane-PMMA Hybrid Coatings on Galvanized Steel Substrates
Siloxane-poly(methyl methacrylate) (PMMA) organic-inorganic hybrid coatings were deposited on galvanized steel by the dip-coating sol-gel technique. Anticorrosion properties, as well as the morphological, surface and structural features were studied. Hybrid coatings were synthesized from tetraethoxy-silane (TEOS) and methyl methacrylate (MMA) as inorganic an
Mat. Res.. Publicado em: 04/12/2015
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11. SÍNTESE E DETERMINAÇÃO DA ESTEREOQUÍMICA RELATIVA DE UM NOVO EPÓXIDO ALDEÍDO CICLOPENTANO MONOTERPENÓIDE
In this study, we report the preparation of a new tetra-substituted epoxide aldehyde cyclopentane, which acts as a starting material for the synthesis of plinol, from (R)-(+)-epoxy-limonene. The synthesis was performed in three steps and resulted in a good yield. The structural determination was performed by 1H and 13C NMR, and the relative stereochemistry w
Quím. Nova. Publicado em: 2015-12
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12. Piperamides from Piper ottonoides by NMR and GC-MS Based Mixture Analysis
The species Piper ottonoides Yuncker (Piperaceae), known as “joão-brandim”, is a shrub that occurs in the Brazilian Amazon rainforest. Its roots and leaves are used in traditional medicine as local anesthetic to treat toothache and sore throat. In this study, the structural characterization in mixture of isobutyl amides present in semi-purified fraction
J. Braz. Chem. Soc.. Publicado em: 2015-11