THE INFLUENCE OF THE ELECTROCHEMICAL TREATMENT ON CU-AL-AG ALLOYS IN DEAERATED 0.5M NAOH

The effect of consecutive cyclic polarization in de-aerated 0.5 M NaOH solutions on the surface microstructure of mechanically polished Cu-Al-Ag alloys of different compositions and heat treatments has been studied using optical microscopy, SEM and EDS. The current peaks of the cyclic polarization curves do not depend on the alloy composition in the composition range studied. The repetitive potential scans between H2 and O2 evolution in alkaline media lead to preferential dissolution of aluminium, the roughness and phase composition of the surface of the alloys changing significantly. The quasistationary I-E curves of the different Cu-Al-Ag alloys studied consist in the superposition of the quasistationary I-E curves of high-purity Cu and Ag, the EDS microanalysis showing that aluminium is not present on the surface of the alloy in these conditions.

Improvement of the ferroelectric properties of ABO(3) (A= Pb, Ca, Ba; B=Ti, Zr) films

High-quality ABO(3)/LaNiO3 (A = Ph, Ca, Ba; B = Ti, Zr) hetero structures have been grown on LaAlO3 (1 0 0) substrate by the chemical solution deposition method and crystallized by a microwave oven technique. The structural, morphological and electric properties were characterized by means of X-ray diffraction (XRD), atomic force microscope (AFM), and dielectric and ferroelectric measurements. XRD patterns revealed single-phase polycrystalline and oriented thin films whose feature depends on the composition of the films. The AFM surface morphologies showed a smooth and crack-free surface with the average grain size ranging from 116 to 300 nm for both LaNiO3 electrode and the ferroelectric films. Dielectric measurements on these samples revealed dielectric constants as high as 1800 at frequency of 100 KHz. Such results showed that the combination of the chemical solution method with the microwave process provides a promising technique to grow high-quality thin films with good dielectric and ferroelectric properties. (c) 2005 Elsevier Ltd. All rights reserved.

Study of the effects of exposure to ionizing irradiation on the materials used for dental restoration

A quantitative study was made about the effects caused by ionizing irradiation on materials used for dental restoration (amalgams, compound resins and compomere), aiming to alleviate in bearers of head and neck cancer, the possible harmful effects of radiotherapy perceived when the repaired teething is within the radiation field. Research also encourages further studies for new alternative materials to be used in dental repair of patients submitted to radiotherapy for head and neck cancer. Test samples were submitted to a gamma radiation beam coming from a cobalt-therapy source and analyzed according to the X-ray fluorescence technique, comparing the chemical composition of the samples before and after irradiation. Radiation detectors such as an ionization chamber and a Geiger-Muller were used to measure the rate of residual dose. Gamma spectrometry with Nal detectors was also performed on the same samples. Results showed that there was no significant change in the chemical composition and that at post-irradiation, samples did not exhibit radiation emission, that is to say they had not become radioactive.

Seasonal morphology of the domestic quail (Coturnix coturnix japonica) testis

A histological study was conducted on the testes of adult domestic quails (Coturnix coturnix japonica) over a year. The results revealed a clear variation of testicular weight, seminiferous tubule diameter, and the thickness and composition of the germinal epithelium over the year. The highest testicular weights were detected at the end of the autumn and during the winter (short-day period), reaching a maximum, together with spermatogenic activity, in September (long-day period in the southern hemisphere). In contrast, both testicular weight and spermatogenic activity were markedly decreased at the end of spring and during summer (long-day periods in the southern hemisphere).

Ultrastructure and histochemistry of the mineral concretions in the midgut of bees (Hymenoptera: Apidae)

Mineral concretions in the digestive cells of bees were examined under transmission electron microscope and histochemically. Ultrastructure shows two types of mineral deposits: 1) mineral concretions which are organized in granules with a striking concentrically layered organization of opaque and clear zones and 2) electron dense granules which appear inside small vacuoles (0.4-0.7 mu m). These two structures are present in the apex of the digestive cells of the posterior midgut. Histochemical data reveal that mineral concretions are composed of calcium, iron and uric acid or its salts while calcium determination gives a positive reaction for electron dense granules. Morphological and chemical similarities between the mineral concretions of bees and those described for other insects suggest that they have an important physiological role regulating the composition of the internal environment and to avoid intoxication. Since concretions and granules are structurally distinct, it is suggested that they are functionally different.

MINERAL COMPOSITION of RAW MATERIAL, SUBSTRATE and FRUITING BODIES of Pleurotus ostreatus IN CULTURE

In a culture of a Pleurotus ostreatus (oyster mushroom) strain, macro and micronutrients of the raw material and the initial and spent substrates were evaluated. Substrates were formulated with sawdust from Simarouba amara Aubl. and Ochroma piramidale Cav. ex. Lam., crushed Bactris gasipaes Kunth and crushed Saccharum officinarum (sugar cane). Samples were solubilized by means of acid digestion (nitric-peridrol). Ca, Mg, Fe, Cu, Zn and Mn were determined by atomic absorption spectrophotometry, Na and K by atomic emission, and P by colorimetry. The mineral composition of the fruiting body varied with the substrates, which made possible the production of a fruiting body rich in K, P Mg and Fe. Potassium was the mineral with the highest content in the fruiting body in all substrates tested (36.83-42.18g.kg(-1)). There was an increase of protein and mineral content in the spent substrate in relation to the initial one.

Denudation history of the Bocaina Plateau, Serra do Mar, southeastern Brazil: Relationships to Gondwana breakup and passive margin development

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

Exploitation of floral resources on Sparattosperma leucanthum (Bignoniaceae): foraging activity of the pollinators and the nectar and pollen thieves

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influence of the cultivation system in the aroma of the volatile compounds and total antioxidant activity of passion fruit

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A description of the growth of the major body components of 2 broiler chicken strains

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

Othonella araguaiana (Bivalvia, Megadesmidae) from the Corumbatai Formation (Midlle [Middle] Permian), Eastern Margin of the Parana Basin: systematic, evolutionary and biostratigraphic significances.

In this study, the occurrence of Othonella araguaiana Mendes, a rare bivalve species is reported for the first time in the Pinzonella illusa biozone, Middle Permian Corumbatai Formation, in the State of São Paulo. This species was originally described in coeval rocks of the Estrada Nova Formation (= Corumbatai) from the Alto Araguaia and Alto Garcas regions, State of Mato Grosso. The specimens of O. araguaiana were found in the base of a bioclastic sandstone bed, a proximal tempestite, in the middle of the Corumbatai Formation, in the city of Rio Claro, São Paulo State. The silicified shells and internal molds are well preserved, showing impressions of muscle scars and other internal anatomic characters (e.g., hinge), never illustrated by previous authors. In his original description, Mendes (1963) called attention to the similarity between O. araguaiana and Terraia aequilateralis, a common veneroid of the Corumbatai Formation. Conversely, Runnegar and Newell (1971) suggested that O. araguaiana belongs to Megadesmidae, being a junior synonym of Plesiocyprinella carinata (the commonest megadesmid of the Passa Dois Group). Our study indicates that O. araguaiana is indeed a megadesmid, but is distinct from the P. carinata. The new occurrence of O. araguaiana demonstrates that a) the paleobiogeographic distribution of this species is wider than previously thought (that it was restricted to the northern part of Parana Basin, Mato Grosso State); b) the molluscan fauna of the Corumbatai Formation (P. illusa biozone) in the State of São Paulo is more diverse and dominated by megadesmids; and c) the composition of the molluscan fauna of the Corumbatai Formation in Alto GarYas, State of Mato Grosso, is essentially the same as that of the P. illusa biozone of the eastern margin of the Parana Basin.

Faunal analysis of the species Anastrepha in the fruit growing complex Gaviao River, Bahia, Brazil

Besides being considered the greatest pests of fruit growing, fruit flies constitute a large obstacle to the growth of the exportation of fresh fruit. Knowledge of the structure of fruit fly communities is of great importance to the bioecological studies of these insects, but there is a lack of information about the faunistic composition of fruit flies in Brazil. The objective of this work was to analysis the composition of the species of Anastrepha, in eleven mango orchards of the fruit growing complex Gaviao River, Bahia, Brazil. These studies were done in 2004 and 2005, in Anage, Caraibas and Belo Campo town, 23 McPhail traps, which collected 798 female fruit flies from the genus Anastrepha. The structure of these communities was evaluated in each orchard by means of faunistic indexes frequency, constancy, dominance, diversity and similarity. The number of species varied from four to eight in each orchard; and the following species was recorded: Anastrepha fraterculus (Wiedemann), Anastrepha obliqua (Macquart), Anastrepha dissimilis Stone, Anastrepha amita Zucchi, Anastrepha distincta Greene, Anastrepha pickeli Lima. Anastrepha sororcula Zucchi and Anastrepha zenildae Zucchi. The most frequent and dominant species were A. fraterculus and A. obliqua. The indexes of diversity varied from 1.01 to 1.62. In general, the similarity between orchards was high (above 55.0%). We observed the formation of groups, one constituted by Frutvale, Carlan, Santa Clara and Panorama orchards; another composed of Cofet, Campo Gaviao and Ouro Verde and a third group formed by Boa Vista orchard. Barra da Onca and Arruda are distinguished from other orchards.

Effect of the fluorination of DLC film on the corrosion protection of aluminum alloy (AA 5052)

It is presented a study conducted on the physical and electrochemical properties of fluorinated a-C:H films deposited onto a commercial aluminum alloy (AA 5052). The coatings were deposited from mixtures of 91% of acetylene and 9% of argon by plasma immersion ion implantation and deposition technique, PIIID. Total gas pressure was 44 Pa and deposition time (t(dep)) was varied from 300 to 1200 s. The depositing plasmas were generated by the application of radiofrequency power (13.56 MHz, 100W) to the upper electrode and high voltage negative pulses (2400 V. 300 Hz) to the sample holder. Fluorine was incorporated in a post-deposition plasma treatment (13.56 MHz, 70W, 13 Pa) generated from sulfur hexafluoride atmosphere. Chemical structure and composition of the films were investigated using infrared reflectance/absorbance spectroscopy and X-ray photoelectron spectroscopy. The corrosion resistance of the layers was determined by electrochemical impedance spectroscopy (EIS) in a 3.5% NaCl solution, at room temperature. Films presented good adhesion to the substrates and are classified as hydrogenated amorphous carbon (a-C:H) with oxygen traces. Fluorine was detected in all the samples after the post-deposition treatment being its proportion independent on the deposition time. Film thickness presented different tendencies with t(dep), revealing the variation of the deposition rate as a function of the deposition time. Such fluorinated a-C:H films improved the corrosion resistance of the aluminum surface. In a general way the corrosion resistance was higher for films prepared with lower deposition times. The variation of sample temperature with t(dep) was found to be decisive for the concentration of defects in the films and, consequently, for the performance of the samples in electrochemical tests. Results are interpreted in terms of the energy delivered to the growing layer by ionic bombardment. (C) 2010 Elsevier B.V. All rights reserved.

An overview of the HIBISCUS campaign

The EU HIBISCUS project consisted of a series of field campaigns during the intense convective summers in 2001, 2003 and 2004 in the State of São Paulo in Brazil. Its objective was to investigate the impact of deep convection on the Tropical Tropopause Layer (TTL) and the lower stratosphere by providing a new set of observational data on meteorology, tracers of horizontal and vertical transport, water vapour, clouds, and chemistry in the tropical Upper Troposphere/Lower Stratosphere (UT/LS). This was achieved using short duration research balloons to study local phenomena associated with convection over land, and long-duration balloons circumnavigating the globe to study the contrast between land and oceans.Analyses of observations of short-lived tracers, ozone and ice particles show strong episodic local updraughts of cold air across the lapse rate tropopause up to 18 or 19 km (420-440 K) in the lower stratosphere by overshooting towers. The long duration balloon and satellite measurements reveal a contrast between the composition of the lower stratosphere over land and oceanic areas, suggesting significant global impact of such events. The overshoots are shown to be well captured by non-hydrostatic meso-scale Cloud Resolving Models indicating vertical velocities of 50-60 m s(-1) at the top of the Neutral Buoyancy Level (NBL) at around 14 km, but, in contrast, are poorly represented by global Chemistry-Transport Models (CTM) forced by Numerical Weather Forecast Models (NWP) underestimating the overshooting process. Finally, the data collected by the HIBISCUS balloons have allowed a thorough evaluation of temperature NWP analyses and reanalyses, as well as satellite ozone, nitrogen oxide, water vapour and bromine oxide measurements in the tropics.

Quality traits and lipid composition of meat from Nellore young bulls fed with different oils either protected or unprotected from rumen degradation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)