Hydro(radio)chemical relationships in the giant Guarani aquifer, Brazil

This investigation was carried out within the Parana sedimentary basin and involved the sampling of 78 pumped tubular wells for evaluating the hydrochemistry and radioactivity due to the nuclides (238)U, (234)U, (222)Ra, (226)Ra, and (228)Ra in the Brazilian part of Guarani aquifer. Several significant correlations were found involving the geostatic pressure, for instance, specific flow rate, CO(3)(2-), SO(4)(2-) temperature, dissolved O(2), free CO(2), pH, redox potential Eh, conductivity, Na, HCO(3)-, CO(3)(2-) , SI(calcite), Cl(-), F(-), SO(4)(2-), and B. Carbonates precipitation was evidenced by inverse correlation between CO(3)(2-) and Ca, Mg, Sr, and Ba, whereas Na exhibited an opposite trend, dissolving rather than precipitating with increasing CO(3)(2-) concentration. An inverse correlation between 3 and K was found, possibly related to the increasing tendency of K to recombine with the thickness of the clayey layers. HCO(3)-played an important role on Na, Ca, Mg, and Sr dissolution. The dissolved U content and (234)U/(238)U activity ratio data were plotted on a two-dimensional diagram that was successfully utilized on identifying an unreported zone of U accumulation, though not necessarily of economic size and grade. The variability in chemical and radionuclides data indicated an important influence of the underlying Paleozoic sediments in the composition of waters from Guarani aquifer. The available data allowed estimate the groundwater residence time by two U-isotopes disequilibrium methods. Values of 45-61 ka were initially calculated, depending on the adopted porosity (15-20%), but a longer residence time (- 640 ka) was also estimated, which is more compatible with the hydraulic conductivity data in Guarani aquifer and groundwater flow velocity occurring at Milk River aquifer, Alberta, Canada. Such time range agrees with previously reported (14)C ages exceeding 30 ka BP at the more central parts of the Parana sedimentary basin. (c) 2005 Elsevier B.V. All rights reserved.

Um sistema de previsão de tempo e de ondas oceânicas para o Atlântico Sul

Um sistema de previsão numérica de tempo e de ondas oceânicas (SPTO) que possa ser operacionalizado no Atlântico Sul é proposto. O SPTO é composto por um modelo atmosférico de área limitada (MAL) e um modelo de ondas de superfície do oceano geradas pelo vento, aplicado em duas versões: uma de malha grossa (MPOMG) e outra de malha fina (MPOMF). O MPOMG abrange uma área de 10(6) km², e tem como finalidade gerar e propagar ondas em regiões remotas à costa brasileira. O MPOMF é aplicado em um domínio 10(4) km² com alta resolução, incorporando irregularidades batimétricas e com as condições iniciais e de fronteiras fomecidas pelo MPOMG. Os modelos utilizam dados de vento à 10 m acima da superfície do oceano. Os arquivos de vento, contendo a evolução espacial e temporais são gerados pelo MAL. Um exemplo de um evento real ocorrido no período de 9 a 11 de agosto de 1988 é apresentado utilizando o acoplamento proposto.

Radio luminescence properties of decaoctahedral BaZrO3

Radioluminescence (RL) emissions were obtained for the BaZrO3 self-assembled nanocrystals under decaoctahedral shape, if produced via microwave-assisted hydrothermal method. Trapped F centers created within the band gap are the result of order-disorder effects, which act as key factors supporting significant RL emission through a detrapping process. The influences of size and morphology on RL properties are take into account. No radiation damage or loss of emission intensity was observed. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Determinação espectrofotométrica de hexametilenotetramina (HMT) em medicamentos, utilizando ácido cromotrópico e forno de micro-ondas

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

Uma discussão sobre as densidades de energia em ondas mecânicas unidimensionais

Estudam-se as médias temporais das densidades das energias cinética e potencial em ondas mecânicas unidimensionais. Demonstra-se que o movimento harmônico simples dos elementos do meio não é condição suficiente nem necessária para que aquelas médias sejam iguais. Isso contradiz as abordagens em textos de Halliday et al. e Nussenzveig.

Síntese hidrotermal assistida por micro-ondas como metodologia sintética eficiente para obtenção da rede metalorgânica [ZN(BDC)(H2O)2]n

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Medição de viscosidade de líquidos pelo método de múltiplas reflexões acústicas com conversão de modo

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

Influência de diferentes tipos de estacas e substratos na propagação assexuada de hortênsia [Hydrangea macrophylla (Thunb.) Ser.]

A hortênsia (Hydrangea macrophylla) é um arbusto semilenhoso de 1,0 a 2,5 m de altura, de folhagem e florescimento decorativos, muito utilizados como flor de vaso e planta para paisagismo. Conduziu-se este trabalho com o objetivo de estudar o enraizamento de estacas de três partes da planta: apical, mediana e basal; em três tipos de substratos: terra, areia e vermiculita, para a formação de mudas. As estacas foram retiradas das plantas matrizes e divididas em segmentos apical, mediano e basal, os quais foram colocados para enraizar em bandejas de isopor, nos substratos areia, terra e vermiculita, em estufa com nebulização. As estacas que apresentaram melhor qualidade de raízes foram as originadas da parte basal do ramo, sendo que o melhor enraizamento foi observado nas estacas colocadas em areia. As estacas obtidas de diferentes partes da planta não se diferenciaram quanto à porcentagem de enraizamento e quanto ao número de brotos formados. Já os substratos que proporcionaram o maior número de brotações foram a areia e a terra. Algumas estacas apresentaram formação de flores, ocorrendo com maior freqüência nas estacas apicais, sem efeito dos substratos. A areia foi o substrato que proporcionou os melhores resultados quanto à qualidade das raízes e porcentagem de enraizamento. O substrato terra foi superior apenas para o número de brotos por estaca, porém não diferenciou estatisticamente da areia. Mudas formadas de estaca da parte basal da planta se mostraram com qualidade superior.

Perfil hormonal de Progesterona durante o ciclo Estral em novilhas Nelore confinadas com Diferentes Ondas de Crescimento Folicular

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Tensile strength of radio frequency cold plasma treated PET fibers - Part 1: Influence of environment and treatment time

This article reports on a series of experiments with polyethylene terepthalate (PET) treated in a radio frequency plasma reactor using argon and oxygen as a gas fuel, for treatment times equal to 5 s, 20 s, 30 s, and 100 s. The mechanical strength modification of PET fibers, evaluated by tensile tests on monofilaments, showed that oxygen and argon plasma treatment resulted in a decrease in the average tensile strength compared with the untreated fibers. This reduction in tensile strength is more significant for argon plasma and is very sensitive to the treatment time for oxygen plasma. Scanning electron microscopy (SEM) used to analyze the effects of cold plasma treatment on fiber surfaces indicates differences in roughness profiles depending on the type of treatments, which were associated with variations in mechanical strength. Differences in the roughness profile, surveyed through an image analysis method, provided the distance of roughness interval, D-ri. This parameter represents the number of peaks contained in a unit length and was introduced to correlate fiber surface condition, before and after cold plasma treatments, and average tensile strength. Statistical analysis of experimental data, using Weibull cumulative distribution and linear representation, was performed to explain influences of treatment time and environmental effects on mechanical properties. The shape parameter, alpha, and density parameter, beta, from the Weibull distribution function were used to indicate the experimental data range and to confirm the mechanical performance obtained experimentally.

Propagação de sapotizeiro (Manilkara zapota L.) por estaquia

Two sapoti tree accesses (Manilkara zapota), native plants of south of Mexico and of America Central, belonging to the Collection of Fruitful Native and Exotic of UNESP/FCAV, Jaboticabal Campus, was studied with relationship to the cutting propagation. The first test consisted of fast immersion of cutting base semi-herbaceous foliage of selected accesses FCAV-III and FCAV-VII. The ttreatments were alcoholic solution (50%) of indolbutiric acid (IBA) in concentrations of 0, 1,000, 3,000, 5,000 and 7,000 mgL(-1). and the cuttings preparing with and without latex exudate washing for a period of 14 hours in recipient with pure water. This trial was set in 5 x 2 x 2 factorial scheme (IBA concentrations x accesses x cutting preparation) The second test consisted the herbaceous foliage immersion of FCAV-III access in IBA concentrations above. Both experiments were distributed in randomized design with four replications and 10 cuttings each. All cuttings were collected in spring and prepared with about 12 cm of length, planted in medium texture vermiculite and carried under conditions intermittent mist spray flashing in chamber with 50% light. The two accesses tested not rooted and treatments were not able to induce the roots emission.

Selection of radio transmitter and attachment method for post-release monitoring of captive-bred reintroduced Red-billed Curassow Crax blumenbachii, Brazil

Long-term monitoring of reintroduced individuals is a central component of many endangered species reintroduction programs. Radio-telemetry techniques are rarely used to monitor reintroduced captive-bred Cracids and few data exist regarding possible adverse effects of radio-tagging Cracids. In this study, we identify an appropriate radio transmitter design and develop a suitable attachment method that minimizes anthropogenic influence and enables long-term, post-release monitoring (2-3 years) of reintroduced captive-bred Red-billed Curassows in the Brazilian Atlantic Rainforest. We also review studies about the effects of different VHF radio transmitter models on survival, reproduction, behavior, and physiology of Galliformes.

Effects of thermal annealing on the semi-insulating properties of radio frequency magnetron sputtering-produced germanate thin films

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Predição de propagação de fissuras através de modelos constitutivos locais e técnica de construção progressiva da trajetória de descontinuidade

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)