7 resultados para Valparaíso and Viña del Mar

em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"


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A new species of electric ray of the family Narcinidae, Discopyge castelloi, is described from the southwestern Atlantic off Argentina. Distinctive characters of the new species are the form of the body, the posterior position of pelvic fins and the manner as pelvic fins join the caudal peduncle, the morphology of the nasal curtain and the presence of small but apparently functional eyes. Discopyge castelloi is the fourth torpediniform species reported from the area. It appears to be very rare on the shelf, though the type locality is separated from that of the paratypes by seven latitude degrees. As in the case of Torpedo puelcha, it is probable that the new species has a normal habitat deeper than that of the available specimens.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Zinc oxide (ZnO) is an electroluminescent (EL) material that can emit light in different regions of electromagnetic spectrum when electrically excited. Since ZnO is chemically stable, inexpensive and environmentally friendly material, its EL property can be useful to construct solid-state lamps for illumination or as UV emitter. We present here two wet chemical methods to prepare ZnO thin-films: the Pechini method and the sol-gel method, with both methods resulting in crystalline and transparent films with transmittance > 85% at 550 nm. These films were used to make thin-film electroluminescent devices (TFELD) using two different insulator layers: lithium fluoride (LiF) or silica (SiO2). All the devices exhibit at least two wide emission bands in the visible range centered at 420 nm and at 380 nm attributed to the electronic defects in the ZnO optical band gap. Besides these two bands, the device using SiO2 and ZnO film obtained via sol-gel exhibits an additional band in the UV range centered at 350 nm which can be attributed to excitonic emission. These emission bands of ZnO can transfer their energy when a proper dopant is present. For the devices produced the voltage-current characteristics were measured in a specific range of applied voltage. (C) 2007 Elsevier B.V. All rights reserved.

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The two fundamental approaches to fission-track dating involve either an explicit determination of the thermal neutron fluence (φ-method) or a calibration against age standards (ζ-method). The neutron fluence measurements are carried out with metal-activation monitors or with uranium-fission monitors, co-irradiated with the samples. Uranium-fission monitors consist of either a thin mono-atomic) film, or a thick fission source (standard uranium glass) irradiated against a muscovite external track detector. In this work, different techniques for performing neutron-fluence measurements were compared: based on thin-film calibration, based on thick-source calibration, and based on gamma spectrometry of co-irradiated metal monitors (Au, Co). The results suggest that more experiments are needed to make all calibrations consistent, including new measurements of the length of etched induced tracks in mica. Also the standard glass calibration carried out with thin films should be confirmed with a greater number of calibrating irradiations. © 2013 Elsevier Ltd. All rights reserved.

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The objective of the present study was to analyze the meat yield for both sexes of the crab Callinectes bocourti in the region of Iguape, Brazil. The carapace width for males was 78.1-114.0 mm (96.7 ± 9.5 mm) and for females 76.0-106.3 mm (93.0 ± 7.8 mm). In males, the total wet weight ranged from 65.53 to 224.36 g (134.04 ± 40.77 g) and for females from 56.66 to 164.74 g (105.93 ± 26.88 g). A comparison of morphological structures revealed that the greatest meat yield was in the carapace (55.1%), followed by the right chela (16.9%), the left chela (15.9%), and the legs (12.1%). The total yield from the males (28.5%) was slightly higher than that from the females (22.1%). In general, portunids yield more meat than other crab species. The results of this study will allow the optimization of meat production for this crab species. Manual meat removal makes the process more expensive. This activity could offer an alternative to the fishing communities that live exclusively from this fishery resource. © 2007 Escuela de Ciencias del Mar Pontificia Universidad Católica de Valparaíso.

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The ambivalent image of the sea is recurrent in Bojunga Nunes’s work. It receives a lot of symbolic meanings in her production, being sometimes a positive and sometimes a negative element. Thus, the sea is used in a utopic way, as a place for pleasure and leisure, and in a dystopic way, as scenery of a rite of passage, which includes the pain and suffering, part of the rite of passage that characterizes the bildungsromans. So, if in some texts the sea assumes a utopic character, being a place of snuggle, security, the ideal to reach, in others it is represented as dystopic, a place of distress, asphyxia and death. In this text we will study the hypothesis that, even in its dark symbolic meaning, in the author’s work the sea is an element of reflection and revelation. Thereby, it assumes metaphorically a sense of magnification of the reader’s expectative, being an element of emancipation. The objective of this text is to present a reflection on the sea’s symbolism on the mentioned texts and its importance for the reader’s formation.