• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • Tagged with
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

On the application of detached eddy simulation turbulence modelling to hydrocyclonic separators for shipboard ballast water treatment

McCluskey, D. K. January 2009 (has links)
There is significant worldwide environmental concern related to the transportation of Invasive Aquatic Species (IAS) by ships ballast water into non-native environments. This has given rise to the development of a vast array of technological ballast water treatment systems. The complex environmental challenges and tight operational characteristics of marine vessels limits the scope of the technologies used for Ballast Water Treatment (BWT). As a result few technologies have progressed beyond the research and development stage; however one of the most promising technologies for ship board use is the cyclonic separator, or hydrocyclone. Despite the use of hydrocyclones in a wide variety of engineering applications they have yet to be successfully adapted towards the removal of suspended sediment and marine organisms from large volumes of ballast water. The following primary objectives of this study have been met: • Via critical review identify the technological solutions for treating ballast water best suited to onboard use. • Define the critical flow regimes evident within hydrocyclonic separators. • Establish a series of Computational Fluid Dynamics (CFD) simulations, evaluating standard turbulence models in order to determine the capacity for commercial CFD to model hydrocyclonic flow. This study has detailed the operational characteristics of ballast water hydrocyclones with the aim of enabling hydrocyclones to be optimised for individual ship configurations. Flow simulations have been conducted using CFD, and in particular the Detached Eddy Simulation (DES) turbulence model. Finally the DES model is shown to be a legitimate turbulence model for hydrocyclonic flow regimes, validated against empirical and experimental data.
2

Caracterização de Vibrio cholerae, V. parahaemolyticus e V. vulnificus em amostras da região costeira do estado de São Paulo, de regiões portuárias brasileiras e de tanques de lastro de navios. / Characterization of Vibrio cholerae, V. parahaemolyticus and V. vulnificus in samples from the coastal region of São Paulo state, Brazilian ports and ship ballast tanks.

Markman, Caroline Viana 12 February 2009 (has links)
A poluição, alteração física do habitat e a introdução de espécies invasoras via água de lastro, representam os maiores impactos antropogênicos para os ambientes costeiros. Foram pesquisadas em amostras da região costeira de S. Paulo, regiões portuárias brasileiras e de tanques de lastro de navios, bactérias das espécies Vibrio cholerae (Vc), V. parahaemolyticus (Vp) e V. vulnificus (Vv) que são as que têm maior implicação na saúde pública. As amostras foram avaliadas levando-se em conta parâmetros físico-químicos e microbiológicos e suas relações com a presença de Vc, Vp e Vv. As relações clonais foram verificadas através das técnicas de ERIC, BOX e REP-PCR. Foram identificadas 90 cepas de Vp e 11 de Vc. Foram observadas correlações entre alguns parâmetros microbiológicos e a presença de vibrios. A análise clonal permitiu verificar a alta diversidade das cepas. Concluiu-se que Vc e Vp são autóctones do ambiente costeiro brasileiro e podem ser tornar reservatórios para determinados fatores associados à virulência, gerando cepas com potencial epidêmico. / Pollution, physical alteration of habitat and the introduction of alien species through ballast water constitute the biggest anthropogenic impacts on coastal environments. We examined samples taken from the coastal region of S. Paulo state, Brazilian ports and ship ballast tanks, for bacteria of the species Vibrio cholerae (Vc), V. parahaemolyticus (Vp) and V. vulnificus (Vv) which have the most significant implication for public health. The samples were evaluated for microbiological and physical-chemical parameters as well as the presence of Vc, Vp and Vv. Clonal relationships of bacterial isolates were determined through ERIC, BOX and REP-PCR. A total of 90 strains of Vp and 11 of Vc were identified. Correlations between some microbiological parameters and the presence of vibrios were observed. The clonal analysis revealed extensive strain diversity. We concluded that Vc and Vp are autochthonous bacteria of the Brazilian coastal environment that can become reservoirs for factors associated with virulence, and are capable of generating strains with epidemic potential.
3

Caracterização de Vibrio cholerae, V. parahaemolyticus e V. vulnificus em amostras da região costeira do estado de São Paulo, de regiões portuárias brasileiras e de tanques de lastro de navios. / Characterization of Vibrio cholerae, V. parahaemolyticus and V. vulnificus in samples from the coastal region of São Paulo state, Brazilian ports and ship ballast tanks.

Caroline Viana Markman 12 February 2009 (has links)
A poluição, alteração física do habitat e a introdução de espécies invasoras via água de lastro, representam os maiores impactos antropogênicos para os ambientes costeiros. Foram pesquisadas em amostras da região costeira de S. Paulo, regiões portuárias brasileiras e de tanques de lastro de navios, bactérias das espécies Vibrio cholerae (Vc), V. parahaemolyticus (Vp) e V. vulnificus (Vv) que são as que têm maior implicação na saúde pública. As amostras foram avaliadas levando-se em conta parâmetros físico-químicos e microbiológicos e suas relações com a presença de Vc, Vp e Vv. As relações clonais foram verificadas através das técnicas de ERIC, BOX e REP-PCR. Foram identificadas 90 cepas de Vp e 11 de Vc. Foram observadas correlações entre alguns parâmetros microbiológicos e a presença de vibrios. A análise clonal permitiu verificar a alta diversidade das cepas. Concluiu-se que Vc e Vp são autóctones do ambiente costeiro brasileiro e podem ser tornar reservatórios para determinados fatores associados à virulência, gerando cepas com potencial epidêmico. / Pollution, physical alteration of habitat and the introduction of alien species through ballast water constitute the biggest anthropogenic impacts on coastal environments. We examined samples taken from the coastal region of S. Paulo state, Brazilian ports and ship ballast tanks, for bacteria of the species Vibrio cholerae (Vc), V. parahaemolyticus (Vp) and V. vulnificus (Vv) which have the most significant implication for public health. The samples were evaluated for microbiological and physical-chemical parameters as well as the presence of Vc, Vp and Vv. Clonal relationships of bacterial isolates were determined through ERIC, BOX and REP-PCR. A total of 90 strains of Vp and 11 of Vc were identified. Correlations between some microbiological parameters and the presence of vibrios were observed. The clonal analysis revealed extensive strain diversity. We concluded that Vc and Vp are autochthonous bacteria of the Brazilian coastal environment that can become reservoirs for factors associated with virulence, and are capable of generating strains with epidemic potential.

Page generated in 0.0714 seconds