Photo-induced transformations in chalcogenide composite layers

Investigations of photo-induced structural transformations (PST) and related changes of optical parameters in the light-sensitive amorphous chalcogenides were extended to composite layers, which consist of a wide band-gap material and an active material, Se60Te40 with a smaller band gap. Photo-stimulated interdiffusion and/or crystallization in layered Se0.6Tc0.4/As0.6Se0.94 and Se0.6Te0.4/SiOx were investigated with respect to their dependence on the compositional modulation of the multilayer at scale-dimensions (similar to3-10nm). It was established that PST due to the interdiffusion and crystallization can be efficiently operated by the composition of the adjacent layers of the multilayer which results in the change of the transformation rate and of the optical relief type (positive or negative). The comparison with a single Se0.6Te0.4 layer and with the known data for amorphous-Se/As2S3 multilayers supports the advantages of composite layers for amplitude-phase optical recording. (C) 2004 Published by Elsevier B.V.

Effects of Self-Etching Adhesive Systems Used in the Dental Modelling Technique on the Cohesive Strength of Composite Resin

This study evaluated the cohesive strength of composite using self-etching adhesive systems (SE) in the lubrication of instruments between layers of composite. The specimens were made by using a Teflon (R) device. SE were used at the interface to lubricate the instruments: Group 1(G1) - control group, no lubricant was used; Group 2(G2) -Futurabond (R) M; Group 3(G3) - Optibond (R) All-In-One; Group 4(G4) - Clearfil (R) SE Bond; Group 5(G5) - Futurabond (R) NR; Group 6(G6) - Adper (R) SE Plus; Group 7(G7) - One Up Bond (R) F. Specimens were submitted to the tensile test to evaluate the cohesive strength. Data were submitted to the ANOVA and Tukey tests. ANOVA showed a value of p = 0.00. The average means (SD): G2 = 11.33(+/-3.44) a, G3 = 15.36(+/-4.06) ab, G4 = 18.9(+/-4.72) bc, G7 = 19.62(+/-4.46) bc, G5 = 21.02(+/-5.09) bc, G6 = 23.39(+/-4.17) cd, and G1 = 28.49(+/-2.89) d. All SE decreased the cohesive strength of the composite, except for Adper (R) SE Plus.

Density functional theory study on the structural and electronic properties of low index rutile surfaces for TiO2/SnO2/TiO2 and SnO2/TiO2/SnO2 composite systems

The present study is concerned with the structural and electronic properties of the TiO2/SnO2/TiO2 and SnO2/TiO2/SnO2 composite systems. Periodic quantum mechanical method with density functional theory at the B3LYP level has been carried out. Relaxed surface energies, structural characteristics and electronic properties of the (I 10), (0 10), (10 1) and (00) low-index rutile surfaces for TiO2/SnO2/TiO2 and SnO2/TiO2/SnO2 models are studied. For, comparison purposes, the bare rutile TiO2 and SnO2 structures are also analyzed and compared with previous theoretical and experimental data. The calculated surface energy for both rutile TiO2 and SnO2 surfaces follows the sequence (110) < (010) < (101) < (001) and the energy increases as (010) < (101) < (110) < (001) and (010) approximate to (110) < (101) < (001) for SnO2/TiO2/SnO2 and TiO2/SnO2/TiO2 composite systems, respectively. SnO2/TiO2/SnO2 presents larger values of surface energy than the individual SnO2 and TiO2 metal oxides and the TiO2/SnO2/TiO2 system renders surface energy values of the same order that the TiO2 and lower than the SnO2. An analysis of the electronic structure of the TiO2/SnO2/TiO2 and SnO2/TiO2/SnO2 systems shows that the main characteristics of the upper part of the valence bands for all the studied surfaces are dominated by the external layers, i.e., by the TiO2 and the SnO2, respectively, and the topology of the lower part of the conduction bands looks like the core layers. There is an energy stabilization of both valence band top and conduction band bottom for (110) and (010) surfaces of the SnO2/TiO2/SnO2 composite system in relation to their core TiO2, whereas an opposite trend is found for the same surfaces of the TiO2/SnO2/TiO2 composite system in relation to the bare SnO2. The present theoretical results may explain the growth of TiO2@SnO2 bimorph composite nanotape.

Properties of individual YBCO layers in a two-layered design for energy-efficient digital data cables

We are developing two-layered Yttrium Barium Copper Oxide (YBCO) thin film structures for energy efficient data links for superconducting electronics and present the results of their property measurements. High temperature superconductors (HTS) are advantageous for the implementation of energy-efficient cables interconnecting low temperature superconductor-based circuits and other cryogenic electronics circuits at higher temperature stages. The advantages of the HTS cables come from their low loss and low dispersion properties, allowing ballistic transfer of low power signals with very high bandwidth, low heat conduction and negligible inter-line crosstalk. The microstrip line cable geometry for typical materials is a two-layered film, in which the two superconducting layers are separated by an insulation layer with a minimized permittivity. We have made a proof of concept design of two YBCO films grown by pulsed laser deposition and then assembled into a sandwich with uniform insulating interlayer of tens of micrometers thick. We report on results obtained from such systems assembled in different ways. Structural and electromagnetic properties have been examined on individual films and on the corresponding sandwich composite. © 2013 IEEE.

Adhesive bonding of resin composite to various titanium surfaces using diferente metal conditioners and a surface modification system

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

Esthetic and function improvement by direct composite resins and biomimetic concept

Aim: This case report describe a resin layering restorative technique based on biomimetic concept to improve esthetics in a patient with dental defects that affected both enamel and dentin in anterior teeth. Background: Severe structural defect in anterior teeth compromises esthetics and it is a high challenge to become the defect imperceptible after the restoration. Case description: A clinical sequence of applying different composite resin layers allowed the reproduction of the interaction between hard dental tissues and the restorative material. Conclusion: This technique achieved a satisfactory final esthetic outcome, preserving sound teeth structure and at same time, improved the quality of life of the young patient. Clinical significance: The utilization of the biomimetic concept to increase a disharmonic smile with dental defects is based in a conservative approach, which reached a satisfactory and esthetic outcome.

Ascorbate electro-oxidation by modified electrodes: Polypyrrole and polypyrrole/Ni(OH)(2) composite thin films

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Breeding potential of maize composite Isanao VF1 in small spacing in the second growing season

The purpose of this study was to verify the breeding potential of the maize composite Isanao VF1 in the second growing season. One hundred and fifty half-sib progenies were evaluated of spacing of 0.45 m, densities of 57,778 and 80,000 plants ha(-1), in a randomized block design with three replications. Gains of 16.0 and 19.2% were estimated for grain Yield, H. I and 10.5% for prolificacy and 12.3 and 12.9% for ear height, respectively, at 57,778 and 80,000 plants ha(-1). The heritabilities for plant height, ear height and grain yield were 65.2 and 61.3%, 64.3 and 66.9% and 53.5 and 63.3%, respectively, confirming the potential for breeding at both densities. The absence of progeny by density interaction indicates that no further selection programs are necessary. The occurrence of segregation for modifier genes for height suggests stabilizing selection based on ear height.

Whole-genome analysis for backfat thickness in a tropically adapted, composite cattle breed from Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Limestone and oyster shell for brown layers in their second egg production cycle

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

Influence of different fat sources on the performance, egg quality, and lipid profile of egg yolks of commercial layers in the second laying cycle

This study was designed to evaluate the effects of different fat sources on the performance, egg quality, and lipid profile of the egg yolks of layers in their second production cycle. The fat sources were cottonseed oil, soybean oil, lard, sunflower oil, or canola oil. Experimental diets were fed to postmolt ISA Brown layers at 70 wk of age and the experimental period was 74 to 86 wk of age. The different fat sources did not influence performance or eggshell quality, but lipid profile of the egg yolk changed as a function of dietary fat sources. In general, the best changes, such as lower level of saturated fatty acids, higher levels of alpha-linolenic acid and DHA, and lower linoleic acid levels, were promoted by the addition of canola oil, but it did not promote enrichment of the eggs with polyunsaturated fatty acids.

Performance of layers submitted to different forced-molting methods and different temperatures

This study was carried out to evaluate the performance and egg quality of laying hens, in their second laying cycle submitted to different forced-molting methods and three environmental temperatures. Six hundred layers were distributed in a completely randomized experimental design with 15 treatments with five replicates of eight birds each, according to 5x3 factorial arrangement (molting methods vs. temperatures). The following forced-molting methods were applied: 90%, 70%, 50% dietary alfalfa inclusion, addition of 2,800 ppm zinc, and feed fasting. Temperatures were: 20 ºC, 27 ºC and 35 ºC. At the end of each period of the second laying cycle, bird performance and egg quality were evaluated. Data were submitted to analysis of variance and means were compared by orthogonal and polynomial contrasts. The highest alfalfa inclusion level (90% alfalfa and 10% basal diet) proved to be efficient as compared to the other methods, independently of temperature.

Genotype by environment interaction for birth and weaning weights of composite beef cattle in different regions of Brazil

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

Modelling the effect of the physical and chemical characteristics of the materials used as casing layers on the production parameters of Agaricus bisporus

The aim of this research was to show the mathematical data obtained through the correlations found between the physical and chemical characteristics of casing layers and the final mushrooms' properties. For this purpose, 8 casing layers were used: soil, soil + peat moss, soil + black peat, soil + composted pine bark, soil + coconut fibre pith, soil + wood fibre, soil + composted vine shoots and, finally, the casing of La Rioja subjected to the ruffling practice. The conclusion that interplays in the fructification process with only the physical and chemical characteristics of casing are complicated was drawn. The mathematical data obtained in earliness could be explained in non-ruffled cultivation. The variability observed for the mushroom weight and the mushroom diameter variables could be explained in both ruffled and non-ruffled cultivations. Finally, the properties of the final quality of mushrooms were established by regression analysis.

Production of Agaricus blazei ss. Heinemann (A. brasiliensis) on different casing layers and environments

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)