Navegação Ciências Exatas e da Terra por Título
Resultados 3428-3447 de 5964
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Nacoes, nacionalidades e a questao federativa : o debate teorico nos campos do liberalismo e do marxismo
(1994) [Artigo de periódico] -
Nanobeams and AFM subject to piezoelectric and surface scale effects
(2018) [Artigo de periódico]Vibration dynamics of elastic beams that are used in nanotechnology, such as atomic force microscope modeling and carbon nanotubes, are considered in terms of a fundamental response within a matrix framework. Te modeling ... -
Nanoemulsion improves the antifungal activity of allylic thiocyanates against yeasts and filamentous pathogenic fungi
(2018) [Artigo de periódico]We report the antifungal and antichemotactic activities of a series of allylic thiocyanates with low toxicity. We also show improved antifungal activity of the most promising compound when used in a nanoemulsion (NE). The ... -
Nano-microstructured, superhydrophobic, and infrared transparent polytetrafluoroethylene/diamond films
(2013) [Artigo de periódico]A self-assembled polytetrafluoroethylene (PTFE) nanostructure is deposited on microcrystalline diamond (MCD) films, by use of physical and chemical vapor deposition in a two-step process, to produce (fully) superhydrophobic ... -
Nanoparticle-coated organic-inorganic microparticles : experimental design and gastrointestinal tolerance evaluation
(2006) [Artigo de periódico]The influences of the spray-drying parameters and the type of nanoparticles (nanocapsules or nanospheres) on the characteristics of nanoparticle-coated diclofenac-loaded microparticles were investigated by using a factorial ... -
Nano-porosity in GaSb induced by swift heavy ion irradiation
(2014) [Artigo de periódico]Nano-porous structures form in GaSb after ion irradiation with 185 MeV Au ions. The porous layer formation is governed by the dominant electronic energy loss at this energy regime. The porous layer morphology differs ... -
Nanoscale density fluctuations in swift heavy ion irradiated amorphous SiO2
(2011) [Artigo de periódico]We report on the observation of nanoscale density fluctuations in 2 μm thick amorphous SiO2 layers irradiated with 185 MeV Au ions. At high fluences, in excess of approximately 5 1012 ions=cm², where the surface is completely ... -
Nanoscale sliding friction versus commensuration ratio : molecular dynamics simulations
(2006) [Artigo de periódico]The pioneer work of Krim and Widom [Phys. Rev. B 38, 12184 (1988)] unveiled the origin of the viscous nature of friction at the atomic scale. This generated extensive experimental and theoretical activity. However, fundamental ... -
Nanostructure-coated diclofenac-loaded microparticles: preparation, morphological characterization, in vitro release and in vivo gastrointestinal tolerance
(2005) [Artigo de periódico]Micropartículas com revestimento nanoestruturado, contendo diclofenaco, foram preparadas e caracterizadas apresentando um rendimento de 80% e taxa de encapsulação de 83%. A análise morfológica (MEV) permitiu a visualização ... -
Nanostructured systems containing an essential oil : protection against volatilization
(2011) [Artigo de periódico]The goal of this study was to evaluate the feasibility of preparing nanocapsules and nanoemulsions using tea tree oil as oily phase aiming to protect its volatilization. The nanostructures presented nanometric mean size ... -
A nanotecnologia como estratégia para o desenvolvimento de cosméticos
(2013) [Artigo de periódico] -
Nanotubos de TiO2 dopados com nitrogênio : comparação das atividades fotocatalíticas de materiais obtidos através de diferentes técnicas
(2012) [Artigo de periódico]TiO2 nanotubes were synthesized by hydrothermal method and doped with three nitrogen compounds to enhance photocatalytic activity under visible light. Catalysts were characterized by X-ray diffraction (XRD), transmission ... -
A não-modernidade de Bruno Latour e suas implicações para a Educação em Ciências
(2018) [Artigo de periódico]Neste trabalho, propomos a visão não-moderna de Bruno Latour como referencial teórico para fundamentar a Educação em Ciências. Apresentamos os conceitos basilares de sua teoria, partindo da Antropologia Simétrica e suas ... -
Natural green coating inhibits adhesion of clinically important bacteria
(2015) [Artigo de periódico]Despite many advances, biomaterial-associated infections continue to be a major clinical problem. In order to minimize bacterial adhesion, material surface modifications are currently being investigated and natural products ... -
Natural language syntax learning and syntactic guided spelling repair
(1991) [Artigo de periódico]It is impossible to define a priori a set of rules to describe alI syntacti cally valid sentences and a dictionary having ali the words a user may write for consul tirig a Natural Language Interface (NLI) for a given ... -
Nature of insoluble material found in the bottom of soybean biodiesel storage tank : chemical and microbiological approach
(2018) [Artigo de periódico]During biodiesel storage, chemical reactions may occur, producing sludges. The aim of this study was to characterize the chemical and microbial composition of the sludge found in a biodiesel storage tank. The material was ... -
Nature of insulating state in the three-band hubbard model : a tight-binding approach
(1995) [Artigo de periódico]We study the three-band Hubbard model, commonly used to describe the copper-oxygen planes of high-Tc superconductors, from the point of view of electronic properties. Utilizing perturbation theory around the atomic limit ... -
Nature of long-range order in stripe-forming systems with long-range repulsive interactions
(2015) [Artigo de periódico]We study two dimensional stripe forming systems with competing repulsive interactions decaying as r−α.We derive an effective Hamiltonian with a short-range part and a generalized dipolar interaction which depends on the ... -
Navigation and interaction in graph visualizations
(2008) [Artigo de periódico]Grafos são bastante utilizados em muitas áreas e diversas aplicações requerem sua visualização. A visualização de grafos é baseada em técnicas para desenho de grafos, interação e navegação, de forma que se auxilie o usuário ... -
Nearest neighbor : the low-mass Milky Way satellite Tucana III
(2017) [Artigo de periódico]We present Magellan/IMACS spectroscopy of the recently discovered Milky Way satellite TucanaIII (Tuc III). We identify 26 member stars in TucIII from which we measure a mean radial velocity of vhel=−102.3±0.4 (stat.)±2.0(sys.) ...