Raman phonon modes of zinc blende InxGa1-xN alloy epitaxial layers

Transverse-optical (TO) and longitudinal-optical (LO) phonons of zinc blende InxGa1-xN (0 less than or equal to x less than or equal to 0.31) layers are observed through first-order micro-Raman scattering experiments. The samples are grown by molecular-beam epitaxy on GaAs (001) substrates, and x-ray diffraction measurements are performed to determine the epilayer alloy composition. Both the TO and LO phonons exhibit a one-mode-type behavior, and their frequencies display a linear dependence on the composition. The Raman data reported here are used to predict the A(1) (TO) and E-1 (TO) phonon frequencies of the hexagonal InxGa1-xN alloy. (C) 1999 American Institute of Physics. [S0003-6951(99)01234-6].

Food and dietary fiber intake by children with or without constipation. Assessment according to the food guide pyramid and the American Health Foundation (AHF)

We studied the ingestion of 54 children with functional constipation (CC) and 41 without (Control), according to the Food Pyramid. A food frequency questionnaire was used, analyzing fruits with or without peel/bagasse, grains whole or refined, and beans separately. Total subjects and 2-6y CC ingested less DF (g/day) than Control (p < 0.05). The majority had high n degrees of dairy and of the meat group servings, but most groups/subgroups did not meet recommendation for fruit and vegetable. A greater proportion of fruit with peel/bagasse in Control than in CC was almost the only difference for 6-12y. There was a discrepancy between the high percentage of children with DF above AHF recommendation and the high percentage of children who did not meet Pyramid recommendations.

Raman spectroscopy analysis of structural photoinduced changes in GeS2 + Ga2O3 thin films

Photoexpansion and photobleaching effects have been observed in amorphous GeS2 + Ga2O3 (GGSO) thin films, when their surfaces were exposed to UV light. The photoinduced changes on the surface of the samples are indications that the structure has been changed as a result of photoexcitation. In this paper, micro-Raman, energy dispersive X-ray analysis (EDX) and backscattering electrons (BSE) microscopy were the techniques used to identify the origin of these effects. Raman spectra revealed that these phenomena are a consequence of the Ge-S bonds' breakdown and the formation of new Ge-O bonds, with an increase of the modes associated with Ge-O-Ge bonds and mixed oxysulphide tetrahedral units (S-Ge-O). The chemical composition measured by EDX and BSE microscopy images indicated that the irradiated area is oxygen rich. So, the present paper provides fundamental insights into the influence of the oxygen within the glass matrix on the considered photoinduced effects. (C) 2010 Elsevier B.V. All rights reserved.

Influence of Environmental Conditioning on the Shear Behavior of Poly(phenylene sulfide)/Glass Fiber Composites

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The effect of the ocean water immersion and UV ageing on the dynamic mechanical properties of the PPS/glass fiber composites

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Employing 2D Projections for Fast Visual Exploration of Large Fiber Tracking Data

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

An In Vitro Comparison of Different Cementation Strategies on the Pull-out Strength of a Glass Fiber Post

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of creatine supplementation on bone quality in the ovariectomized rat model: an FT-Raman spectroscopy study

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A disposable chitosan-modified carbon fiber electrode for dengue virus envelope protein detection

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of surface treatment on fatigue behavior of metal/carbon fiber laminates

The tension-tension fatigue behavior of metal/fiber laminates (MFLs) has been investigated. These MFLs were produced with carbon fiber and by treating the aluminum foil to promote adhesion bonding by two methods: sulfuric-boric-oxalic acid anodization (SBOA) and chromic acid anodization (CAA). The surface treatments were evaluated by scanning electron microscopy (SEM) techniques and roughness measurements. It was observed that MFL specimens produced with SBOA treatments presents comparable mechanical results when compared with MFLs produced with CAA treatment. Microstructural observations of the fracture surfaces by SEM show hackle formation is the predominant damage mechanism.

Metal-Organic Semiconductor Nanostructures for Surface-Enhanced Raman Scattering

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The Effect of Water Immersion and UV Radiation Aging on the Shear Behavior of Woven Continuous Fiber/PEI Laminates

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)