Tangent Surface
Mostrando 1-9 de 9 artigos, teses e dissertações.
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1. Dielectric Behavior of α-Ag2WO4 and its Huge Dielectric Loss Tangent
The microwave-assisted hydrothermal method was used to obtain α-Ag2WO4. Rietveld refinement confirmed that α-Ag2WO4 is stable in the orthorhombic phase, without secondary phase. However, field-effect scanning electron microscope analysis showed that α-Ag2WO4 nanorods surfaces contain silver nanoparticles, confirmed by the X-ray photoelectron spectroscopy
Mat. Res.. Publicado em: 02/09/2019
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2. Dumbbell Shaped Microstrip Broadband Antenna
Abstract In this article, a dumbbell shaped microstrip broadband microstrip antenna with partial ground plane is presented, The overall dimension of the proposed antenna is 20 × 15 × 1.5 mm3 and is fabricated on FR4 substrate which has electrical permittivity of 4.3 and loss tangent of 0.025. FR4 is a low cost and easily available. The thickness of the sub
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2019-03
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3. 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
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4. Chemical modifications in lignocellulosic fibers to obtain and use in biosensor array phenolic derivative of LCC and the biosorption of metals / Modificações químicas em fibras lignocelulósicas para obtenção e aplicação em biocompósitos de matriz fenólica derivada de LCC e na biossorção de metais
In this work, lignocellulosic fibers from two sources (sisal and banana pseudo stem) were used as reinforcing agents in the preparation of phenolic matrix composites derived from cashew nut shell liquid (CNSL) and as material to adsorb toxic metals (Pb+2, Ni+2, Cd+2, Zn+2 and Cu+2). Surface changes were induced in the sisal fibers by immersion in alkali solu
Publicado em: 2008
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5. Avaliação da contaminação por metais solúveis e metais pesados de uma área de disposição de resíduos sólidos urbanos com o acompanhamento da pluma de contaminação sob a influência das estações de chuvas
The present study has the goal of mechanisins that guide the metals behavior in the subterranean water and in the groud, scouring from a controlled scree. The quality of the groundwater in the scree controlled by the district of Londrina was evaluated using phisic and chemist parameters, soluble metals, heavy metals, nitrate, biochemistry demand of oxygen (D
Publicado em: 2007
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6. Singularities of Ruled Surface in R3 / Singularidades das Superfícies Regradas em R3
Estudaremos as singularidades genéricas de superfécies regradas em R3. O objetivo do trabalho é mostrar que as singularidades genéricas que ocorrem no conjunto das superfícies regradas são as mesmas que ocorrem no conjunto das aplicações diferenciáveis de R2 em R3, enquanto que as singularidades genéricas das superfícies desenvolvíveis, que forma
Publicado em: 2004
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7. Estudo de diferentes processos de torração de café por metodo convencional e microondas
The objective of this study was to contribute a greater knowledge about different coffee roasting processes by both conventional and microwave methods, comparing the effects on different qualities of arabica coffee (hard to better, soft and very soft). Thus experimental coffee roasting conditions were developed [domestic and rapid (industrial) at 210°C and
Publicado em: 2001
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8. Analise do contato roda-trilho e sua influencia na vida em serviço de rodas ferroviarias
The objective of this work is to analyze the stresses in the wheel-rail contact and to compare them with the contact strength for wheel and rail steels, aiming to estimate the service life for wheels. Those stresses are fundamental to study the shelling in wheels of high load freight railroad cars. The stresses were calculated using Hertz s theory and the Fi
Publicado em: 2000
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9. Electric field-induced reorganization of two-component supported bilayer membranes
Application of electric fields tangent to the plane of a confined patch of fluid bilayer membrane can create lateral concentration gradients of the lipids. A thermodynamic model of this steady-state behavior is developed for binary systems and tested with experiments in supported lipid bilayers. The model uses Flory’s approximation for the entropy of
The National Academy of Sciences of the USA.