32 resultados para Hecla (Ship)
em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"
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The numerical model FUNWAVE was adapted in order to simulate the generation and propagation of ship waves to shore, including phenomena such as refraction, diffraction, currents and breaking of waves. Results are shown for Froude numbers equal to 0.8, 1.0 and 1.1, in order to verify the refraction of the wave pattern, identify breaking conditions and to investigate the wave generation scheme as a moving pressure at the free surface. © 2009 World Scientific Publishing Co. Pte. Ltd.
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Tributyltin exposure is the primary cause of imposex development in gastropods, making them excellent bioindicators. The present research represents the first examination of butyltin (BT) contamination in surface sediments associated with imposex in Leucozonia nassa and L. ocellata in a harbour complex area in Espirito Santo, southeastern Brazil. The objectives of this study were to evaluate the organotin pollution in the area and to assess the sensitivity of both species to BT pollution through imposex development. Specimens were collected between 2007 and 2010 and the sediments were sampled in 2007. Imposex intensity was evaluated based on the percentage of imposexed females, the relative penis length index (RPLI) and the average value of the vas deferens sequence index (VDSI). BTs were analysed using gas chromatography equipped with a pulsed flame photometric detector (PFPD). The results demonstrated the occurrence of elevated concentrations of BTs in the sediment ranging from 383.7 to 7172.9 ng Sn g(-1), indicating a severe contamination of the area, which was confirmed by the biological monitoring results. Our findings also indicated that L. ocellata is a less sensitive species than L. nassa and that this differential sensitivity plays a key role in the distributions of the populations of both species in the studied area.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Tubos de aço são transportados diariamente em todo o mundo, por caminhão, trem ou navio. Conseqüentemente, danos de transporte, podem ocorrer com freqüência e regularidade. O tipo de dano particular selecionado para este estudo foi o de trinca por fadiga, o qual é considerado como um dos mais críticos. Neste trabalho foram estudados tubos de aço fabricados de acordo com os requisitos da norma API 5L [1]. Foram efetuadas caracterizações químicas, mecânicas e metalográficas de um tubo com diâmetro 609,6 mm e espessura 15,87 mm grau X-65. A simulação do transporte por navio de tubos de aço foi feita submetendo-se seções de tubo com comprimento igual a 0,1 metro, a ciclos de fadiga por meio de máquina servo-hidráulica. Foi possível concluir que em tubos soldados, a região adjacente ao cordão de solda é a mais crítica, e que quando o posicionamento do tubo na carga é efetuado de maneira que a solda fique apoiada sobre alguma superfície rígida, a ocorrência de trinca por fadiga torna-se possível principalmente se os procedimentos de manuseio, carregamento e transporte não forem executados da maneira como recomendada pelos fabricantes de tubos e pela norma API [2].
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Since the nineteenth century ships have been using ballast water (BW) for safety, stability, propulsion and maneuverability, as well as to redress loss of fuel weight and water consumption, and to maintain structural stress at acceptable levels. Ballast water has been spreading many non-native species around the globe, but little is known about the extent and potential significance of ship-mediated transfer of microorganisms. The global movements of ballast water by ships create a long-distance dispersal mechanism for human pathogens that may be important in the worldwide distribution of microorganisms, as well as for the epidemiology of waterborne diseases. Only a few studies have been carried out on this subject, most of them involving ballast water containing crustacean larvae and phytoplankton. Specialized microbiological studies on these waters are necessary to avoid a repeat of what happened in 1991, when epidemic cholera was reported in Peru and rapidly spread through Latin America and Mexico. In July of 1992, Vibrio cholerae was found in the USA and the Food and Drug Administration (FDA) determined that it came from ballast water of ships whose last port of call was in South America. In Brazil, just a few studies about the subject have been performed. An exploratory study by the Brazilian National Health Surveillance Agency (Agencia Nacional de Vigilancia Sanitaria - ANVISA) found in ballast water different microorganisms, such as fecal coliforms, Escherichia coli, Enterococcus faecalis, Clostridium perfringens, coliphages, Vibrio cholerae O1 and Vibrio cholerae non-O1. Until now, Brazil has been focusing only on organisms transported to its territory from other countries by ballast water, to avoid their establishment and dissemination in Brazilian areas. Studies that can assess the probability that water ballast carries pathogenic microorganisms are extremely important, as is the examination of ships that arrive in the country. Treatment of the human infections caused by BW exists but none is completely safe and efficient.
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Marine biological invasions have been regarded as one of the major causes of native biodiversity loss, with shipping and aquaculture being the leading contributors for the introductions of alien species in aquatic ecosystems. In the present study, five aquatic alien species (one mollusk, three crustaceans and one fish species) were detected during dives, shore searches and from the fisheries on the coast of the Delta do Parnaiba Environmental Protection Area, in the States of Piaui and Maranhao, Northeastern Brazil. The species were the bicolor purse-oyster Isognomon bicolor, the whiteleg shrimp Litopenaeus vannamei, the giant river prawn Macrobrachium rosenbergii, the Indo-Pacific swimming crab Charybdis hellerii and, the muzzled blenny Omobranchus punctatus. Ballast water (I. bicolor, C. hellerii, and O. punctatus) and aquaculture activities (L. vannamei and M. rosenbergii) in adjacent areas are the most likely vectors of introduction. All exotic species found have potential impact risks to the environment because they are able to compete against native species for resources (food and habitat). Isognomon bicolor share the same habitat and food items with the native bivalve species of mussels and barnacles. Litopenaeus vannamei share the same habitat and food items with the native penaeids such as the pinkspot shrimp Farfantepenaeus brasiliensis, the Southern brown shrimp Farfantepenaeus subtilis, and the Southern white shrimp Litopenaeus schmitti, and in the past few years L. vannamei was responsible for a viral epidemics in the cultivation tanks that could be transmitted to native penaeid shrimps. Charybdis hellerii is also able to cause impacts on the local fisheries as the species can decrease the populations of native portunid crabs which are commercialized in the studied region. Macrobrachium rosenbergii may be sharing natural resources with the Amazon River prawn Macrobrachium amazonicum. Omobranchus punctatus shares habit with the native redlip blenny Ophioblennius atlanticus and other fishes, such as the frillfin goby Bathigobius soporator. Some immediate remedial measures to prevent further introductions from ballast water and shrimp farm ponds should be: (i) to prevent the release of ballast water by ship/vessels in the region; (ii) to reroute all effluent waters from shrimp rearing facilities through an underground or above-ground dry well; (iii) to install adequate sand and gravel filter which will allow passage of water but not livestock; (iv) outdoor shrimp pounds located on floodable land should be diked, and; (v) to promote environmental awareness of those directly involved with ballast water (crews of ship/vessels) and shrimp farms in the region. Rev. Biol. Trop. 58 (3): 909-923. Epub 2010 September 01.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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A ocorrência uma dermatite pápulo-pruriginosa em toda a tripulação de um navio comercial filipino em Salvador, BA, foi associada ao contato com mariposas do gênero Hylesia. Esta enfermidade insólita é causada por cerdas corporais das mariposas (flechettes). O relato dos casos serve como alerta para possíveis situações semelhantes.
Resumo:
Occurrence and the effects of butyltin compounds (BTs) have been studied for some years, mainly in countries of the Northern Hemisphere. Due to widespread use of tributyltin compounds (TBTs) and considering their deleterious effects, it is necessary to conduct studies on its occurrence, especially in the marine environment because of its excessive use in coatings of ship hulls to prevent fouling. Moreover, it was important to extend the evaluation to areas where there is no current information about their occurrence. The present work reports the occurrence of BTs in marine sediments of São Paulo state, Brazil. Commercial and leisure harbor sampling sites were selected because these areas are potentially exposed to BTs from antifouling paints used on ship hulls. Analytical conditions for organotin analysis in marine sediments were optimized for GC with pulsed flame photometric detection. Detection limits ranged from 8.4 to 66.3 ng g(-1) using a 610-nm filter, and the linearity range was 20-500 ng g(-1). Concentration levels of BTs were highest in Santos harbor (360 ng g(-1) TBT in average) and Guaruja marina (670 ng g(-1) TBT in average), which seems to be related to intensive boat traffic. Lower levels of BTs were observed in Cananeia, where only fishing boats are present (50 ng g(-1) TBT in average). (C) 2002 Elsevier B.V. B.V. All rights reserved.
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A highly sensitive amperometric biosensor for determination of carbamate pesticides directly in water, fruit and vegetable samples has been evaluated, electrochemically characterized and optimized. The biosensor strip was fabricated in screen printed technique on a ceramic support using silver-based paste for reference electrode, and platinum-based paste for working and auxiliary electrodes. The working electrode was modified by a layer of carbon paste mixed with cobalt(II) phthalocyanine and acetylcellulose. Cholinesterase (ChE) enzymes with low enzymatic charge were immobilized on this layer. The operational simplicity of the biosensor consists in that a small drop (similar to 50 mu l) of substrate or sample is deposited on a horizontally positioned biosensor strip representing the microelectrochemical cell. The working potential of the biosensor was 370 mV versus Ag/AgI on a ship reference electrode preventing the interference of electroactive species which are oxidable at more positive potentials. The biosensor was applied to investigate the degradation of two reference ChE inhibitors in freeze dried water under different storage conditions and for direct determination of some N-methylcarbamates (NMCs) in fruit and vegetable samples at ppb concentration levels without any sample pretreatment. A comparison of the obtained results for the total carbamate concentration was done against those obtained using HPLC measurements. (C) 1999 Elsevier B.V. B.V. All rights reserved.
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The transfer formulas are used to compute hourly values of sensible and latent heat exchanges for the period July 29 to July 31, 1974. Also, values of eddy shearing stress at the sea surface, Bowen's ratio and dissipation of kinetic energy are computed. The data used cover part of the GATE period for station 20 occupied by the Brazilian Naval Ship R/V Sirius in the Equatorial Atlantic (0730 N 4000 W). The variations in the computed values are studied in relation to rainfall and the synoptic situation. © 1980 D. Reidel Publishing Co.
Resumo:
The numerical model FUNWAVE+Ship simulates the generation and propagation of ship waves to shore, including phenomena such as refraction, diffraction, currents and breaking of waves. The interaction of two wave trains, generated by ships moving either in the same direction at different speeds or in opposite directions, is studied. Focus is given to the wave orbital velocities and to the free surface pattern.
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We are investigating the combination of wavelets and decision trees to detect ships and other maritime surveillance targets from medium resolution SAR images. Wavelets have inherent advantages to extract image descriptors while decision trees are able to handle different data sources. In addition, our work aims to consider oceanic features such as ship wakes and ocean spills. In this incipient work, Haar and Cohen-Daubechies-Feauveau 9/7 wavelets obtain detailed descriptors from targets and ocean features and are inserted with other statistical parameters and wavelets into an oblique decision tree. © 2011 Springer-Verlag.
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To properly describe the interactions between the ocean and atmosphere, it is necessary to assess a variety of time and spatial scales phenomena. Here, high resolution oceanographic and meteorological data collected during an observational campaign carried out aboard a ship in the tropical Atlantic Ocean, on May 15-24, 2002, is used to describe the radiation balance at the ocean interface. Data collected by two PIRATA buoys, along the equator at 23°W and 35°W and satellite and climate data are compared with the data obtained during the observational campaign. Comparison indicates remarkable similarity for daily and hourly values of radiation fluxes components as consequence of the temporal and spatial consistence presented by the air and water temperatures measured in situ and estimated from large scale information. The discrepancy, mainly in the Sao Pedro and Sao Paulo Archipelago area, seems to be associated to the local upwelling of cold water, which is not detected in all other estimates investigated here. More in situ data are necessary to clarify whether this upwelling flow has a larger scale effect and what are the meteorological and oceanographic implications of the local upwelling area on the tropical waters at the Brazilian coast.
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Torsional vibration predictions and measurements of a marine propulsion system, which has both damping and a highly flexible coupling, are presented in this paper. Using the conventional approach to stress prediction in the shafting system, the numerical predictions and the experimental torsional vibration stress curves in some parts of the shafting system are found to be quite different. The free torsional vibration characteristics and forced torsional vibration response of the system are analyzed in detail to investigate this phenomenon. It is found that the second to fourth natural modes of the shafting system have significant local deformation. This results in large torsional resonant responses in different sections of the system corresponding to different engine speeds. The results show that when there is significant local deformation in the shafting system for different modes, then multi-point measurements should be made, rather than the conventional method of using a single measurement at the free end of the shaft, to obtain the full torsional vibration characteristics of the shafting system.