Polarization Characteristics
Mostrando 1-12 de 70 artigos, teses e dissertações.
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1. A New Miniaturized Low-Profile and Stable Dual-Band FSS with 2.5D Structure for ISM Bands
Abstract Based on 2.5-Dimensional (2.5D) frequency selective surface (FSS) structures, a new miniaturized frequency selective surface structure is proposed in this work to operate as a bandreject filter in the 2.4 GHz (2400 to 2483.5 MHz) and 5 GHz (5150 to 5350 MHz and 5470 to 5725 MHz) ISM (Industrial, Scientific, and Medical) bands. The FSS has the metall
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2022
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2. A Compact, Wideband, Dual Polarized CPW-Fed Asymmetric Slot Antenna for Wireless Systems
Abstract Wideband, dual sense circularly polarized (CP), asymmetric circular slot fed by coplanar waveguide is proposed and designed. Dual polarizations are obtained by using a horizontal stub to the feed line and embedding the L-shaped strip onto the slotted ground plane. The simulated result of impedance bandwidth shows wideband performance is produced by
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-09
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3. Investigation of Physicochemical Characteristics of Heavy, Medium and Blend Crude Petroleum on Corrosion Resistance of AISI 1020 Carbon Steel
This work investigates the influence of the physicochemical characteristics of heavy (17.5 °API), medium (28.3 °API) and blend (50% heavy + 50% medium) crude petroleum on corrosion of AISI 1020 carbon steel at 25.0 ± 1.0°C. The corrosion resistance of steel was analyzed by electrochemical impedance spectroscopy, potentiodynamic polarization, and scanning
Mat. Res.. Publicado em: 05/12/2019
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4. Concentration of skim milk by reverse osmosis: characterization and flow decline modelling
Resumo Neste trabalho, as características físico-químicas e o declínio de fluxo durante o processo de osmose inversa foram analisados. O declínio de fluxo foi avaliado utilizando-se resistências em série, os modelos de bloqueio de poro e um segundo modelo conjugado, que consiste na combinação de resistências decorrentes dos bloqueios de poro e do d
Braz. J. Food Technol.. Publicado em: 25/11/2019
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5. Produção e caracterização de revestimentos de ligas metálicas Cu-Sn em banho eletrolítico contendo glicina: ensaios preliminares
RESUMO Os problemas relacionados à corrosão são frequentes, podendo ocorrer nas mais variadas áreas, tais como, nas indústrias química, petroquímica, naval, de construção civil e automobilística, dentre outros setores produtivos. Portanto, métodos para prevenir a corrosão devem ser empregados para evitar a perda de materiais e o uso de revestimen
Matéria (Rio J.). Publicado em: 16/09/2019
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6. A 50Ω Microstrip Line Fed Shorted Hexagonal Microstrip Antennas with Reduced Cross-Polarization
Abstract A Hexagonal Microstrip Antenna (HMSA) is an approximation to a Circular MSA (CMSA), which is not symmetrical over two principal planes, unlike a CMSA. Consequently, two types of feed positions are feasible for each X and Y-axes. When a quarter-wave transformer or inset feed is used to match the edge impedance of the HMSA, it becomes asymmetrical ove
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 19/06/2019
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7. Os protestos no Brasil em tempos de crise (2011-2016)
Este artigo se propõe a analisar as características dos protestos no Brasil entre 2011 e 2016, um contexto socioeconômico e político marcado pelas contradições e pelo ocaso dos governos petistas. A análise está baseada em um banco de dados de protesto constituído a partir do jornal Folha de S. Paulo. Sustentamos que os protestos antecedem a eclosão
Opin. Publica. Publicado em: 16/05/2019
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8. Avaliação Microestrutural e Resistência à Corrosão de uma Junta Dissimilar entre um Aço de Alta Resistência e Baixa Liga e Aço um Inoxidável Duplex
Resumo A união entre materiais dissimilares tem sido amplamente aplicada na indústria de petróleo e gás. Em geral, este tipo de soldagem é mais sensível às diferenças de composição química existente entre os metais envolvidos. Diante dessa perspectiva, este trabalho tem por objetivo avaliar, por união autógena, a microestrutura de uma junta sold
Soldag. insp.. Publicado em: 16/05/2019
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9. Efectos del uso de electrolitos soportes en ensayos electroquímicos de la aleación Al-4%Mg expuesta a bioetanol combustible
ABSTRACT The growth of world energy demand directly affects the consumption of petroleum-based fuels, increasing the negative impact of the use of these fuels and the decrease of crude oil reserves. This creates an opportunity for the use of fuels that are more efficient, of low environmental impact and, above all, of a renewable nature. Bioethanol is a biof
Matéria (Rio J.). Publicado em: 19/07/2018
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10. Obtención y caracterización de recubrimientos de biovidrio sobre la aleación de Mg AZ31
ABSTRACT The ideal material for a metal bone prosthesis must undergo a gradual corrosion in vivo, without releasing toxic components, while acting as a support and facilitating the growth of bone tissue, until a replacement is completed by the regenerated bone. . Biodegradable magnesium alloys have been studied because of their excellent mechanical propertie
Matéria (Rio J.). Publicado em: 19/07/2018
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11. Anatomical characterization of ultra-structures, biominerals and histolocalization of metabolites in leaves of Genipa americana
Abstract Inserted in one of the largest families among the Angiosperms, Genipa americana L., Rubiaceae, can be found in all Brazilian territory, presenting great medicinal importance, where several uses have been attributed. In view of this, this work has the purpose of analyzing the ultrastructural, biomineral, phytochemical and histochemical characteristic
Rev. bras. farmacogn.. Publicado em: 2017-10
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12. Effect of Activated Carbons on the Dielectric and Microwave Properties of Natural Rubber Based Composites
The effect of six different types of activated carbons has been studied in view of their applicability as functional fillers upon the dielectric and microwave properties of natural rubber based composites. It is found that the textural characteristics of the studied active carbons exert influence both on the real part of dielectric permittivity and dielectri
Mat. Res.. Publicado em: 06/07/2017