Structural Gradient
Mostrando 1-12 de 330 artigos, teses e dissertações.
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1. Finite element evaluation of the effects of curvature in Lamb waves for composites structural health monitoring
Abstract This work presents the effect of the high curvature to thickness ratio on the characteristics of Lamb Waves propagating over the skins of composite structures. It is accessed how the curvature on composite skins affects the group velocity of the symmetrical (S0) and asymmetrical (A0) wave modes. It is also accessed the gradient of curvature effect,
Lat. Am. j. solids struct.. Publicado em: 11/10/2018
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2. Propiedades físicas y cristalinas del Cd1-xZnxTe (0 ≤ x ≤ 1)
ABSTRACT Cd1-xZnxTe (0 ≤ x ≤ 1) and ZnTe are II-VI semiconductors, which are used in single crystalline structure to improve their crystalline and electrical properties. The CZT and ZnTe must possess high crystalline and electrical quality to be used, the first in x or γ-ray detectors, and as substrates for suitable epitaxial films for detecting IR radi
Matéria (Rio J.). Publicado em: 19/07/2018
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3. Estructuras de titanio con gradiente de porosidad – fabricación por el método de partículas espaciadoras y caracterización
ABSTRACT It has proposed the use of porous titanium to reduce the problem of mechanical incompatibility, which occurs between such material used in implants and bone. The pores introduction in titanium decreases its elastic modulus by bringing it closer to that of both cortical and trabecular bones. This paper describes titanium fabrication by powder metallu
Matéria (Rio J.). Publicado em: 19/07/2018
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4. Estudio Ab-initio de propiedades estructurales, elásticas y electrónicas de nanohilos core/shell
ABSTRACT This Zinc oxide (ZnO) is widely used in different electronic devices due to its thermal, electronic, and piro-piezoelectric properties. Some of these properties are noticeable improvement at the nanoscale, specially when ZnO together with other material create heterostructures. Recently, core/shell nanowires have been synthesized in order to raise t
Matéria (Rio J.). Publicado em: 19/07/2018
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5. Fish habitat associations along a longitudinal gradient in a preserved coastal Atlantic stream, Brazil
ABSTRACT Habitat conditions at multiple scales are one of the major factors structuring ichthyofauna. Thus, we analyzed the fish habitat associations along the headwater-mouth gradient of a coastal Atlantic stream. We categorized the sampling sites into habitat units, so that in the middle reach these categories were statistically differentiated into riffles
Zoologia (Curitiba). Publicado em: 01/02/2018
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6. Bird diversity along a gradient of fragmented habitats of the Cerrado
ABSTRACT Understanding the factors that affect biodiversity is of central interest to ecology, and essential to species conservation and ecosystems management. We sampled bird communities in 17 forest fragments in the Cerrado biome, the Central-West region of Brazil. We aimed to know the communities structure pattern and the influence of geographical distanc
An. Acad. Bras. Ciênc.. Publicado em: 11/12/2017
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7. Improved Electronic Structure and Optical Performance of Bi2Te3-xSex From First-principle Calculations Within TB-mBJ Exchange Potential
Using the first-principle calculations of density functional theory within the (FP-LAPW) method, we have investigated the structural, electronic and optical properties of Bi2Te3-xSex alloys with compositions x = 0, 1, 2 and 3 of Se. The generalized gradient approximation functional of Wu and Cohen (GGA-PBE) is used to calculate ground state structural parame
Mat. Res.. Publicado em: 17/11/2017
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8. Floristic-functional variation of tree component along an altitudinal gradient in araucaria forest areas, in Southern Brazil
ABSTRACT We aimed to investigate the taxonomic and functional variations of tree component of Araucaria Forest (AF) areas located along an altitudinal gradient (700, 900 and 1,600 m asl), in the southern region of Brazil. The functional traits determined were leaf area, specific leaf area, wood density, maximum potential height and dispersal syndromes and de
An. Acad. Bras. Ciênc.. Publicado em: 24/07/2017
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9. The HPLC Fingerprint Analysis of Selected Cirsium Species with Aid of Chemometrics
Twelve Cirsium sp. methanolic extracts were analyzed using high-performance liquid chromatography gradient elution method with run time of 45 min. Four Kinetex (150 × 4.6 mm) chromatographic columns (C18 5 µm, C18 2.6 µm, pentafluorophenyl 5 µm, phenyl-hexyl 5 µm) and mobile phase consisting of methanol/water/formic acid 1% were used. Eight standards (n
J. Braz. Chem. Soc.. Publicado em: 2016-10
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10. Development and Applications of Highly Functional Al-based Materials by Use of Metastable Phases
This paper reviews the features of alloy components, structure and mechanical properties, physical and chemical properties of metastable Al-based alloys developed by use of various liquid or vapor quenching-induced phases such as amorphous, quasicrystalline, nanocrystalline, nanocomposite, supersaturated solid solution and structure gradient phases. As advan
Mat. Res.. Publicado em: 04/12/2015
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11. Application of the Complex Variable Semi-analytical Method for Improved Displacement Sensitivity Evaluation in Geometrically Nonlinear Truss Problems
AbstractThe application of gradient-based methods to structural optimization problems usually requires the determination of displacement sensitivities with respect to design variables. In this regard, it is important to have at hand comprehensive methods for sensitivity analysis, which show stability, efficiency and accuracy. Particularly, application of the
Lat. Am. j. solids struct.. Publicado em: 2015-05
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12. Poaceae communities in the savannas of the Amazon Estuary in Brazil
We sought to identify the major environmental factors that affect the diversity and distribution of Poaceae in the savannas of the Amazon Estuary. The study was conducted across seven areas of savanna in the Amazon Estuary, within which 160 subplots of 1 m² each were established within four 10 × 100 m plots. Soil samples were collected at a depth of 0-20 c
Acta Bot. Bras.. Publicado em: 2014-12