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  • 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.
41

The Red Sea – Dead Sea Water Conveyance project and human security in Jordan and Israel

Österman, Lilja Emilia January 2019 (has links)
The main purpose of this research is to investigate Jordan and Israel's participation in the Red Sea – Dead Sea Water Convenience project from human security point of view. The Red Sea – Dead Sea Water Conveyance project is planned to desalinate water from Red Sea to the Dead Sea and provide fresh water to Jordan, Israel and possibly Palestine. I use a human security approach in this investigation because it has a broader people-centered security perspective. This approach guides the research to consider water related issues and challenges in Jordan and Israel to which the project can be a possible solution. I use qualitative content analysis to investigate the issues identified by Jordan and Israel, and how the project is estimated to address these challenges. I argue that the estimated benefits that the implementation of the project provides for human well-being in Jordan and Israel makes them to participate in this project.
42

Characterisation and desalination of typical South African abalone farm effluent sea water

Steynberg, Leander Duvan 12 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Nearly all South African abalone farms function on an intensive pump-ashore, flow-through system. Large volumes of sea water that are pumped ashore flow through abalone or kelp harvesting tanks and finally gravitate back to the ocean. If the effluent from an abalone farm can be desalinated without permanent membrane fouling, then sea water reverse osmosis (SWRO) technology can be integrated effectively with established abalone farms without having to increase the farms’ intake system capacities. Without the need to construct and maintain an intake system, the overall cost of desalination can be reduced. Therefore, the aim of this study was to determine the feasibility and viability of integrating a SWRO desalination plant with a typical South African abalone farm. The project focused on four areas of concern, namely: - characterisation of typical South African abalone farm water - SWRO desalination plant pilot study and membrane fouling behaviour - general operation of a typical abalone farm and its implications for desalination - cost estimates and implications for the integration of an SWRO desalination plant with an abalone farm During a nine-month on-site investigation, sea water turbidity was reduced by up to 43% from a mean value of 0.82 NTU in the influent stream to 0.47 NTU in the combined effluent stream from the abalone tanks. Even with spikes in the influent turbidity, the turbidity of the combined effluent from all abalone tanks (excluding tank flush water) remained below 1 NTU. Dissolved organic carbon (DOC) in both the influent and combined effluent remained below 1 mg/litre. Ultrafiltration (UF) was selected as pre-treatment to the reverse osmosis (RO) in order to minimise potential fouling of the RO membranes. Membrane compaction of both the UF and RO membranes contributed significantly to initial flux losses – as much as 18% for the polyethersulfone (PESM) UF membranes and 20% for the thin film composite (TFC) polyamide RO membrane. However, this is comfortably in line with typical compaction values quoted in the literature. Without pre-flocculation, the UF was able to operate at a specific flux between 45 and 55 litre/m2/h (LMH) and recoveries ranging between 60 and 75%. Corresponding trans-membrane pressure (TMP) ranged between 0.59 and 0.76 bar. With ferric chloride pre-flocculation at a concentration of 3 mg/litre (as Fe3+) the UF could be operated at notably lower TMP values between 0.11 and 0.36 bar. These results indicate that provision should definitely be made for pre-flocculation when using UF as pre-treatment, despite the fact that the DOC concentrations and turbidity of the abalone farm effluent are quite low (DOC <1 mg/litre, NTU <1). It furthermore highlights the inability of DOC and turbidity alone to predict the membrane fouling potential of water. A better indicator of membrane fouling potential, albeit not perfect, is the modified fouling index (MFI0.45). This index follows a linear trend with foulant concentration and serves as a good indicator of the filterability of water. On-site measurements showed an increase in mean MFI0.45 values from 29 s/litre2 for the influent to 48 s/litre2 for the effluent from the abalone tanks, thereby confirming the need for pre-flocculation as part of UF pre-treatment. Chemically enhanced backwashing (CEB) of the UF membrane at least every 24 hours was found to be essential for its stable operation. Therefore, UF with pre-flocculation (3 mg/litre Fe3+) and regular CEB can be used effectively as pre-treatment method for the desalination of abalone farm effluent water. An RO ‘feed-and-bleed’ system was used to simulate the typical performance of the last membrane in a full-scale RO membrane bank. This RO membrane performed well with no signs of extreme fouling. The membrane produced a good quality permeate – for the last membrane in a membrane bank – reducing the TDS of the RO feed from 33 493 mg/litre to 969 mg/litre. These results compared well with simulated values by Reverse Osmosis System Analysis (ROSA; an RO simulator by DOW), indicating a TDS reduction from 33 271 mg/litre to 1 409 mg/litre at a feed pressure of 56 bar, and overall recovery of 44%. A steady performance of the RO membrane during the pilot study indicated that it is possible to desalinate abalone effluent water without notable permanent membrane fouling. A stable normalised flux rate of 8 LMH was achieved and RO membrane integrity remained intact with a salt rejection that ranged from 98.0 to 98.5%. No sudden reduction in permeate flux was observed as a result of fouling by unknown constituents present in the UF permeate. DBNPA (a non-oxidising disinfectant) was dosed once per week at a concentration of 10 – 30 mg/litre for 30 minutes. Scaling was controlled effectively by means of an antiscalant dosed at a concentration of 11 – 12 mg/litre in the feed stream. The CIP frequency was not optimised but a CIP frequency of once every 6 – 8 weeks appeared to be more than adequate to prevent permanent membrane fouling Advantages of integrating an SWRO desalination plant with a South African abalone farm include: - no lengthy and costly environmental impact assessment (EIA) is required to build a new intake system - shared capital and operational cost of intake system - dual incentive to keep constant good quality water flowing through the farm - early warnings regarding occurrences such as algal bloom and red bait - shared operational and management cost to keep pipelines clean - electricity saved (pumps for intake system) Disadvantages of integrating an SWRO desalination plant with a South African abalone farm include: - will require diverting of the abalone tank wash water from regular effluent - possible water ‘down-times’ due to maintenance operations on abalone farm Based on information from the literature the fixed capital cost depreciation rate (FCCDR) typically contributes approximately 40% and the operation and maintenance (O&M) cost typically contributes 60% to the unit production cost (UPC) of desalinated water. Furthermore, a SWRO desalination plant’s intake system can contribute between 5% and 33% to the FCCDR, depending on the nature and design of the plant. Consequently, the intake system can contribute between 2% and 13% of the UPC of desalinated sea water. This implies possible cost savings of between R0.15/m3 and R2.37/m3 for the production of fresh water (depending on site-specific design factors) when desalinating sea water effluent from on-shore abalone tanks. Integration of an SWRO desalination plant with a South African abalone farm is feasible and viable, provided that the necessary steps and precautions are taken to ensure a smooth and stable operation of the SWRO desalination plant. Cost savings on the part of all the stakeholders are possible if the correct contract can be negotiated. / AFRIKAANSE OPSOMMING: Byna alle Suid Afrikaanse perlemoenplase funksioneer op ‘n seewater deurvloeistelsel. Groot volumes seewater word aan wal gepomp en vloei deur die perlemoen of kelp-oes tenks. Hierdie water vloei dan uiteindelik terug na die oseaan as gevolg van swaartekrag. Indien die afvalwater van die perlemoenplase ontsout kan word sonder permanente membraanbevuiling kan seewater tru-osmose (SWTO)-tegnologie effektief met gevestigde perlemoenplase geïntegreer word sonder om die plase se water inname-stelsels se kapasiteite te vergroot. Sonder die behoefte aan uitbreiding en instandhouding van ‘n water inname-stelsel by so ‘n plaas behoort die totale koste van ontsouting aansienlik minder te wees. Die doel van hierdie studie was dus om die uitvoerbaarheid en lewensvatbaarheid van ‘n integrasie van ‘n SWTO ontsoutingsaanleg met ‘n tipiese Suid Afrikaanse perlemoenplaas te ondersoek. Ten einde dit te doen, het die projek op vier areas van belang gefokus, naamlik: - karakterisering van tipiese Suid-Afrikaanse perlemoenplaas water - SWTO ontsoutingsaanleg loodsstudie en membraan bevuilingsgedrag - algemene bedryf van ‘n tipiese perlemoenplaas en die implikasies vir ontsouting - kosteberamings en koste-implikasies met betrekking tot die integrasie van ‘n SWTO ontsoutingsaanleg met ‘n perlemoenplaas Gedurende ‘n nege maande op-perseel ondersoek is seewater troebelheid verminder met tot 43% van 'n gemiddelde waarde van 0.82 NTU in die invloeistroom tot 0.47 NTU in die gekombineerde afvalwaterstroom wat die tenks verlaat. Selfs met skerp wisseling in die invloeistroom troebelheid, bly afvalwaterstroom troebelheid deurgaans onder 1 NTU met die uitsondering van tenk spoelwater. Opgeloste organiese koolstof (OOK) in beide die invloeistroom en die gekombineerde afvalwaterstroom het deurgaans onder 1 mg/liter gebly. Ultrafiltrasie (UF) is gebruik as voorbehandeling vir die tru-osmose (TO) om sodoende potensiële bevuiling van TO membrane te minimaliseer. Membraan kompaksie van beide die UF en TO het merkbaar bygedra tot aanvanlike deurvloeiverliese – so veel as 18% vir die poli-etersulfoon (PESM) UF membrane en 20% vir die dun film saamgestelde (DFS) poli-amied TO membraan. Hierdie is egter gerieflik binne die tipiese kompaksiewaardes soos aangehaal in die literatuur. Sonder flokkulasie was die UF in staat tot temperatuur aangepaste deurvloeitempo van tussen 45 en 55 liter/m2/h (LMH) teen herwinningstempo’s tussen 60 en 75%. Ooreenstemmende trans-membraandrukkings (TMD) het gewissel tussen 0.59 en 0.76 bar. Met ysterchloried voor-flokkulasie teen 'n konsentrasie van 3 mg/liter (as Fe3+) kon die UF teen merkbaar laer TMD waardes bedryf word – tussen 0.11 en 0.36 bar. Hierdie resultate dui daarop dat daar beslis voorsiening vir pre-flokkulasie gemaak moet word wanneer UF as voorbehandeling gebruik word, ten spyte van die feit dat die OOK konsentrasie en troebelheid van die afvalwater van die perlemoenplaas redelik laag is (OOK <1 mg / liter, troebelheid <1 NTU). Verder lig dit die onvermoë uit om OOK en troebelheid alleen te gebruik om membraanbevuilingspotensiaal van water te voorspel. ‘n Beter aanwyser van membraanbevuilingspotensiaal, alhoewel nie perfek nie, is die aangepaste bevuilingsindeks (MFI0.45). Hierdie bevuilingsindeks volg ‘n lineêre neiging met die konsentrasie van onsuiwerhede en dien as ‘n goeie aanwyser van die filtreerbaarheid van water. Op-perseel metings het getoon dat ‘n toename in gemiddelde MFI0.45 waardes van 29 s/litre2 vir die invloeistroom tot 48 s/litre2 vir die afvalstroom van die perlemoentenks die behoefte vir voor-flokkulasie as deel van UF voorbehandeling bevestig. Chemies versterkte terugspoeling (CVT) van die UF membrane ten minste elke 24 uur is noodsaaklik gevind ten einde bestendige werking te verseker. Dus kan UF met voor-flokkulasie (3 mg/liter Fe3 +) en gereelde CVT effektief as voorbehandeling metode vir die ontsouting van perlemoenplaas afvalwater gebruik word. ‘n TO ‘voer-en-bloeistelsel’ is gebruik om die tipiese prestasie van die laaste membraan in ‘n volskaalse TO membraanbank te simuleer. Hierdie TO membraan het goed presteer sonder tekens van buitensporige membraanbevuiling. Vir die laaste membraan in ‘n membraanbank het die membraan goeie gehalte finale water gelewer – ‘n vermindering van die totaal opgeloste stowwe (TOS) van die TO voerwater van 33 493 mg/liter tot 969 mg/liter is behaal. Hierdie resultate het goed vergelyk met gesimuleerde waardes deur Reverse Osmosis Analysis System (ROSA, ‘n TO simulator deur DOW) wat ‘n TOS vermindering van 33 271 mg/liter tot 1 409 mg/liter by ‘n voerdruk van 56 bar en ‘n algehele herwinningstempo van 44% aandui. ‘n Bestendige werking van die TO membraan tydens die loodsstudie het getoon dat dit moontlik is om perlemoenplaas afvalwater te ontsout sonder merkwaardige permanente membraanbevuiling. 'n Stabiele genormaliseerde deurvloeitempo van 8 LMH is bereik en TO membraan integriteit het ongeskonde gebly met 'n sout verwerping wat gewissel het van 98.0 tot 98.5%. Geen skielike afname in finale water deurvloeitempo is waargeneem as gevolg van bevuiling deur onbekende onsuiwerhede in die UF finale water nie. DBNPA (‘n nie-oksiderende ontsmettingsmiddel) is een keer per week teen ‘n ‘n konsentrasie van 10 – 30 mg / liter vir 30 minute gedoseer. Mineraal skaalvorming is effektief beheer deur die dosering van ‘n anti-skaalmiddel teen 11 – 12 mg/liter in die TO voerstroom. Die skoonmaak-in-plek (SIP) frekwensie is nie ge-optimeer nie, maar ‘n SIP een keer elke 6 – 8 weke is meer as voldoende gevind om mikrobiese bevuiling te voorkom. Voordele van die integrasie van 'n SWTO ontsoutingsaanleg met 'n Suid-Afrikaanse perlemoenplaas sluit die volgende in: - geen lang en duur omgewings impak ontleding (OIO) is nodig vir die bou van ‘n nuwe inname-stelsel nie - gedeelde kapitaal en operasionele koste van inname-stelsel - tweeledige aansporing om konstant goeie gehalte watervloei deur die plaas te verseker - vroegtydige waarskuwings ten opsigte van gebeurtenisse soos rooigety - gedeelde bedryfs- en bestuurskoste om voerpype skoon te hou Nadele van die integrasie van 'n SWTO ontsoutingsaanleg met 'n Suid-Afrikaanse perlemoenplaas sluit die volgende in: - vereis herleiding van perlemoentenk spoelwater weg van gereelde afvalwater - moontlike watervloei-aftye weens instandhoudingsbedrywighede op die perlemoenplaas Gebaseer op inligting uit die literatuur dra die vaste kapitaal koste waardeverminderings-koers (VKKWK) gewoonlik ongeveer 40% en die bedryfs- en instandhoudingskoste (B&I) ongeveer 60% by tot die produksiekoste per eenheid (PKE) van ontsoute water.Verder kan ’n SWTO ontsoutingsaanleg se inname-stelsel tussen 5% en 33% tot die VKKWK bydra afhangende van die aard en ontwerp van die aanleg. Gevolglik kan die inname-stelsel tussen 2% en 13% tot die PKE van ontsoute seewater bydra. Dit impliseer ‘n moontlike kostebesparing van tussen R0.15/m3 en R2.37/m3 vir die produksie van vars water wanneer die afvalwater van perlemoentenks ontsout word. Integrasie van 'n SWTO ontsoutingsaanleg met 'n Suid-Afrikaanse perlemoenplaas is uitvoerbaar en lewensvatbaar indien die nodige stappe en voorsorgmaatreëls geneem is om ‘n vlot en bestendige werking van die SWTO ontsoutingsaanleg te verseker. Kostebesparings vir alle belanghebbendes (beleggers) is moontlik indien daar oor die korrekte kontrak onderhandel kan word.
43

Variations in past and present ocean circulation assessed with U-series nuclides

Thomas, Alexander Llewellyn January 2006 (has links)
This thesis considers the use of two U-series nuclides – 231 Pa and 230 Th – as proxies for studying ocean circulation. A total of six water-column profiles of 231 Pa, 230 Th, and 232 Th have been measured from two regions of the southwestern Indian Ocean: the Madagascar and Mascarene Basins; and the southeastern continental margin of South Africa. Measurement by MC-ICP-MS of 10 litre water samples is possible for samples with as little as 4 and 2 fg of 231 Pa and 230 Th and yields typical uncertainties of 6% and 14% respectively. These profiles show that the scavenging and advection histories of water masses can affect their 231 Pa concentration, with distinct variations superimposed on a general increase in concentration with depth due to reversible scavenging. A 1D particle scavenging model is used to show that sedimentary (231 Paxs /230 Thxs )0 is most representative of the (231 Pa/230 Th) of the bottom most water mass at any one locality, although in turn this water mass (231 Pa/230 Th) will be dependent not only on its advection and scavenging history but also the 231 Pa and 230 Th concentrations of the overlying water masses during advection. Acknowledgment that sedimentary (231 Paxs /230 Thxs )0 is “set” by the bottommost water mass is important for interpretation of scenarios where changes in depth of circulation, as well as circulation strength, may have occurred. A record of sedimentary (231 Paxs /230 Thxs )0 has been recovered from a 6 m Kasten core from the Mascarene Basin covering the past 140 ka, in order to reconstruct flow of AABW into the basin. The (231 Paxs /230 Thxs )0 measured is below the production ration of 0.093 and shows no significant variation. This indicates that (231 Paxs /230 Thxs )0 is sensitive to changes in particle productivity and circulation at this location and that there has been little or no change in either environmental variable over the last full interglacial-glacial cycle. This finding is in contrast to other ocean basins, particularly the North Atlantic, where large changes in circulation are observed.
44

Estudo da alteração na absorção da luz monocromática (transmitância) como parâmetro de contaminação do mar por hidrocarbonetos

Sieczka Junior, Edson Luiz 27 June 2013 (has links)
CAPES / O monitoramento em tempo real da água do mar em ambientes críticos, como na entrada de portos e de canais de navegação, é necessário para evitar grandes contaminações do meio ambiente marinho, principalmente em regiões costeiras. A contaminação mais recorrente é por derramamento de hidrocarbonetos. Um indicativo de contaminação por óleo, em tempo real, viabiliza a atuação imediata dos setores responsáveis. Tal medida pode evitar que as impurezas se espalhem por uma área maior, o que torna o processo de limpeza e descontaminação mais rápido e eficaz. Este estudo visa detectar alterações no comportamento físico da água do mar quando existir contaminação por hidrocarbonetos. O parâmetro físico a ser estudado é a variação na curva de transmitância da água do mar, com específicos comprimentos de onda, quando existir contaminação na amostra. A variação da absorção da onda eletromagnética detectada pelo foto sensor pode indicar que a amostra de água esteja contaminada por hidrocarbonetos. O equipamento base para a tomada de dados das curvas de transmitância é o espectrofotômetro, que tem como característica a capacidade de realizar uma varredura em uma faixa de comprimento de onda eletromagnética compreendida entre 190 nm a 1100 nm. A avaliação dos resultados é feita utilizando uma placa de aquisição do espectro de um LED de 400 nm. Dois métodos foram realizados utilizando a mesma fonte de radiação, o primeiro com incidência horizontal da luz na amostra de água (próximo à superfície) e o segundo com incidência vertical, submetendo a radiação à absorção causada pela coluna de água e contaminante (gasolina e querosene). Os resultados obtidos neste trabalho apresentam uma queda bem significativa da transmitância em função do aumento da concentração de poluente (hidrocarbonetos) na água, nas faixas mais pertinentes de cada substância, com suas diferentes estruturas moleculares. O ponto do espectro de maior sensibilidade para este hidrocarboneto na medição da transmitância está em 360 nm. Utilizando a lei de Lambert-Beer, foi calculada a correlação exponencial dos pontos obtidos com um determinado comprimento de onda, em 360 nm esta correlação é superior a 99%. O método utilizado e os resultados levantados possibilitam o desenvolvimento e aplicação de um sensor óptico para sensoriamento da água do mar baseado na variação da absorção da luz em função do aumento da concentração de contaminantes (hidrocarbonetos), e a utilização da lei de Lambert-Beer para estimar a concentração deste produto na água. / The real time monitoring of seawater in critical environments such as ports entrances and navigation channels is needed in order to avoid major contaminations of the marine environment especially in coastal regions. The most recurrent contamination is hydrocarbon spills. A real time contamination indicator enables immediate action from the responsible sectors. Such measurement might prevent impurities from spreading into a greater area, resulting in faster and more effective cleaning and decontamination process. This study aims to detect changes in the physical behavior of the sea water when hydrocarbon contamination exists. The physical parameter under study is the variation in the transmittance curve of seawater, with specific wavelengths, when there is contamination in the sample. The absorption variation of the electromagnetic wave detected by the photo sensor can indicate that the water sample is contaminated by hydrocarbons. The base equipment for collecting data from the transmittance curves is the spectrophotometer, which is able to perform a scan on an electromagnetic wavelength range between 190 nm to 1100 nm. Two methods were performed using the same radiation source, the first one with horizontal light incidence into the water sample (near-surface) and the second one with vertical incidence, subjecting radiation to absorption caused by the water column and contaminant (gasoline and kerosene). The results obtained in this study show a significant decrease of transmittance in function of the increase in concentration of pollutant (hydrocarbon) in the water, in the more relevant ranges of each substance, with their different molecular structures. The hydrocarbon used in the evaluation of both methods validation was gasoline. The spectrum point of greater sensitivity in measuring the hydrocarbon transmittance is in 360 nm. Using the Lambert-Beer law it was calculated exponential correlation of points obtained with a specific wavelength, in 360 nm this correlation is greater than 99%. The method and results raised enabled the development and application of an optical sensor for sensing seawater according to the variation of light absorption in function of the increasing contaminants concentration (hydrocarbons), and using the Lambert-Beer law to estimating the concentration of product in water.
45

Estudo da alteração na absorção da luz monocromática (transmitância) como parâmetro de contaminação do mar por hidrocarbonetos

Sieczka Junior, Edson Luiz 27 June 2013 (has links)
CAPES / O monitoramento em tempo real da água do mar em ambientes críticos, como na entrada de portos e de canais de navegação, é necessário para evitar grandes contaminações do meio ambiente marinho, principalmente em regiões costeiras. A contaminação mais recorrente é por derramamento de hidrocarbonetos. Um indicativo de contaminação por óleo, em tempo real, viabiliza a atuação imediata dos setores responsáveis. Tal medida pode evitar que as impurezas se espalhem por uma área maior, o que torna o processo de limpeza e descontaminação mais rápido e eficaz. Este estudo visa detectar alterações no comportamento físico da água do mar quando existir contaminação por hidrocarbonetos. O parâmetro físico a ser estudado é a variação na curva de transmitância da água do mar, com específicos comprimentos de onda, quando existir contaminação na amostra. A variação da absorção da onda eletromagnética detectada pelo foto sensor pode indicar que a amostra de água esteja contaminada por hidrocarbonetos. O equipamento base para a tomada de dados das curvas de transmitância é o espectrofotômetro, que tem como característica a capacidade de realizar uma varredura em uma faixa de comprimento de onda eletromagnética compreendida entre 190 nm a 1100 nm. A avaliação dos resultados é feita utilizando uma placa de aquisição do espectro de um LED de 400 nm. Dois métodos foram realizados utilizando a mesma fonte de radiação, o primeiro com incidência horizontal da luz na amostra de água (próximo à superfície) e o segundo com incidência vertical, submetendo a radiação à absorção causada pela coluna de água e contaminante (gasolina e querosene). Os resultados obtidos neste trabalho apresentam uma queda bem significativa da transmitância em função do aumento da concentração de poluente (hidrocarbonetos) na água, nas faixas mais pertinentes de cada substância, com suas diferentes estruturas moleculares. O ponto do espectro de maior sensibilidade para este hidrocarboneto na medição da transmitância está em 360 nm. Utilizando a lei de Lambert-Beer, foi calculada a correlação exponencial dos pontos obtidos com um determinado comprimento de onda, em 360 nm esta correlação é superior a 99%. O método utilizado e os resultados levantados possibilitam o desenvolvimento e aplicação de um sensor óptico para sensoriamento da água do mar baseado na variação da absorção da luz em função do aumento da concentração de contaminantes (hidrocarbonetos), e a utilização da lei de Lambert-Beer para estimar a concentração deste produto na água. / The real time monitoring of seawater in critical environments such as ports entrances and navigation channels is needed in order to avoid major contaminations of the marine environment especially in coastal regions. The most recurrent contamination is hydrocarbon spills. A real time contamination indicator enables immediate action from the responsible sectors. Such measurement might prevent impurities from spreading into a greater area, resulting in faster and more effective cleaning and decontamination process. This study aims to detect changes in the physical behavior of the sea water when hydrocarbon contamination exists. The physical parameter under study is the variation in the transmittance curve of seawater, with specific wavelengths, when there is contamination in the sample. The absorption variation of the electromagnetic wave detected by the photo sensor can indicate that the water sample is contaminated by hydrocarbons. The base equipment for collecting data from the transmittance curves is the spectrophotometer, which is able to perform a scan on an electromagnetic wavelength range between 190 nm to 1100 nm. Two methods were performed using the same radiation source, the first one with horizontal light incidence into the water sample (near-surface) and the second one with vertical incidence, subjecting radiation to absorption caused by the water column and contaminant (gasoline and kerosene). The results obtained in this study show a significant decrease of transmittance in function of the increase in concentration of pollutant (hydrocarbon) in the water, in the more relevant ranges of each substance, with their different molecular structures. The hydrocarbon used in the evaluation of both methods validation was gasoline. The spectrum point of greater sensitivity in measuring the hydrocarbon transmittance is in 360 nm. Using the Lambert-Beer law it was calculated exponential correlation of points obtained with a specific wavelength, in 360 nm this correlation is greater than 99%. The method and results raised enabled the development and application of an optical sensor for sensing seawater according to the variation of light absorption in function of the increasing contaminants concentration (hydrocarbons), and using the Lambert-Beer law to estimating the concentration of product in water.
46

Avaliação de impactos ambientais causados por metais traço em água, sedimento e material biológico na Baia de São Marcos, São Luís - Maranhão / Assessment of Environmental Impacts caused by trace in water, sediments and b in a São Marcos Bay, São Luís Maranhão.

Sousa, Janyeid Karla Castro 16 July 2009 (has links)
Made available in DSpace on 2015-05-14T13:21:24Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1778944 bytes, checksum: c42dcebf9f7394f2955a83c25a92b1b5 (MD5) Previous issue date: 2009-07-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The present work shows an assessment of the environmental conditions of São Marcos Bay in the trace metal (Cu, Pb, Zn, Cd, Ni, Fe, Al and Mn) levels in water, sediment and fish. For this evaluation three points of collections were selected in the proximities of the Itaqui port, considering the drought and rain periods and the tide conditions. Physico-chemical parameters of the water were evaluated, such as: pH, temperature, salinity and conductivity. The results for these analyses showed that just the salinity (30 ) presented a value below the minimum indicated to characterize as saline water. The other parameters are in agreement with the expected for this type of water. The ecotoxicity test in the water of the Bay demonstrated poisonous effects in all sampling points, therefore confirmed the presence of substances that influence on the system in São Marcos Bay. The quantification of Cu, Pb, Zn, Cd, Ni, Fe, Al and Mn metals was carried out with Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) thecnique while Anodic Stripping Voltammetry with mercury film electrode was used to determine the other metals that were not quantified by ICP-OES in water samples. Fe and Al concentrations were the most abundant elements in water and sediment with 5,41 and 7,82 mg L-1 average in water for Fe and Al, respectively and 3427 and 4200 mg L-1 maximum for Fe and Al in sediments. For the fish samples only the Pb, Cd and Ni metals were not detected. The CONAMA 357/05 resolution was used for water results discussion and ANVISA 685/08 for the fish results discussion. / O presente trabalho apresenta uma avaliação das condições ambientais da Baía de São Marcos com relação aos níveis de metais-traço Cu, Pb, Zn, Cd, Ni, Fe, Al e Mn em água, sedimento e peixes. Para esta avaliação foram selecionados três pontos de coletas nas proximidades da região portuária do Itaqui, considerando os períodos de seca e chuva e as condições da maré (vazante e enchente). Parâmetros físico-químicos da água como: pH, temperatura, salinidade e condutividade foram avaliados. Os resultados para estas análises mostraram que apenas a salinidade apresentou-se abaixo de 30 que é o valor mínimo para caracterizar uma água como salina. Os demais parâmetros estão de acordo com o esperado para este tipo de água. O teste de ecotoxicidade realizado na água da Baía demonstrou efeitos tóxicos em todos os pontos de amostragem, confirmando-se que na Baía de São Marcos há a presença de substâncias que influenciam sobre o sistema de ensaio. A quantificação dos metais Cu, Pb, Zn, Cd, Ni, Fe, Al e Mn foi realizada por Espectroscopia de emissão ótica com plasma indutivamente acoplado (ICP-OES) e por voltametria de redissolução anódica com eletrodo de filme de mercúrio os metais que não foram quantificados por ICP-OES em amostras de água. Concentrações de Fe, Al foram as mais abundantes em água e sedimento de fundo com média de 5,41 e 7,82 mg L-1 em água para Fe e Al, respectivamente e máxima de 3427 e 4200 mg L-1 para Fe e Al em sedimentos. Para as amostras de peixes apenas os metais Pb, Cd e Ni não foram detectados. Os resultados foram discutidos com base na Resolução 357/05 CONAMA e Portaria 685/08 da ANVISA para água e peixe, respectivamente.
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ComparaÃÃo da qualidade bacteriolÃgica da Ãgua marinha e da areia seca e molhada de duas praias do litoral leste do Cearà / Comparison of the bacteriological quality of the sea water and the dry and wet sand to two beaches of the east coast of CearÃ

Denise Terezinha Lippmann Monteiro 24 June 2013 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / A qualidade microbiolÃgica das Ãguas e areias das praias, principalmente das localizadas em Ãreas de grande desenvolvimento econÃmico social e turÃstico, caso de Aquiraz, deveria ser uma preocupaÃÃo constante dos ÃrgÃos pÃblicos, uma vez que muitas doenÃas sÃo veiculadas por esses microcosmos, sobretudo Ãs pessoas com deficiÃncia no sistema imunolÃgico, caso dos idosos e crianÃas. No perÃodo de Fevereiro a Maio/2012, semanalmente, foi realizado o monitoramento das Ãguas e das areias (seca e molhada) das praias do Iguape e do PresÃdio, ambas em Aquiraz, CearÃ. Os objetivos da pesquisa foram comparar quantitativamente a microbiota bacteriana presente nas Ãguas do mar e na areia dessas duas praias. Foram avaliados para a Ãgua e areia: o NMP de Coliformes Termotolerantes (CT), de Escherichia coli (E.coli), de Enterococcus spp. (ENT) e a contagem de leveduras (somente no sedimento). A tÃcnica usada para estimar a populaÃÃo de CT, E.coli e Enterococcus spp., tanto nas Ãguas como nas areias (seca e molhada) foi a dos tubos mÃltiplos e o mÃtodo de Contagem PadrÃo em Placas (CPP) utilizado para estimar a populaÃÃo das leveduras. Os resultados obtidos para as amostras de Ãgua do mar foram comparados com a ResoluÃÃo do Conselho Nacional do Meio Ambiente n 274/2000. Os dados obtidos para areia seca e molhada foram comparados à LegislaÃÃo de Portugal devido à ausÃncia de legislaÃÃo no Brasil. De acordo com os resultados obtidos, a Ãgua da praia do Iguape apresentou uma situaÃÃo de risco maior do que a praia do PresÃdio. As areias secas e molhadas apresentaram uma maior contaminaÃÃo na praia do Iguape. As amostras de areia seca do Iguape e do PresÃdio apresentaram uma contaminaÃÃo superior Ãs de areia molhada. Foi observada uma maior contaminaÃÃo de levedura na praia do Iguape. A areia seca do Iguape està mais contaminada com Enterococcus e leveduras do que a areia seca da Praia do Presidio. Recomenda-se uma aÃÃo eficaz de monitoramento pelas autoridades sanitÃrias no sentido de eliminar as fontes de contaminaÃÃo por bactÃrias patogÃnicas ao homem. / The microbiological quality of the water and sand on sea shores, especially in the vicinity of urbanized areas and tourist facilities, requires careful and permanent monitoring. An array of diseases may be transmitted by pathogenic microorganisms in aquatic environments to which children, the elderly and the immuno deficient tend to be particularly susceptible. The present study is a quantitative evaluation of the bacterial microbiota of sea water and wet and dry sand collected at two points (Iguape and Presidio) along the coast of CearÃ, Northeastern Brazil, once a week between February and May 2012. The study parameters included MPN of thermotolerant coliforms (CT), Escherichia coli (EC) and Enterococcus spp. (ENT) (sand and water), and yeast count (YC) (sand only). The first four parameters ( CT, EC and ENT) were quantified with the multiple tube method, while YC was determined with standard plate count. The results obtained for sea water samples were compared with the maximum contaminant levels (MCLs) specified in Resolution #274/2000 issued by CONAMA [Brazilian Council for the Environment], while the results obtained for dry and wet sand were compared with the MCLs specified in the Portuguese legislation (in the absence of equivalent Brazilian regulations). Both sea water and dry and wet sand were found to be more contaminated at Iguape than at Presidio. At both locations, dry sand was more contaminated than wet sand. Yeast counts were also higher in samples from Iguape. Dry sand from Iguape yielded higher ENT and YC values than dry sand from Presidio. The local health authorities are advised to improve the monitoring of the microbiological quality of the water and sand at these locations and identify possible sources of contamination.
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Biodegradação de querosene por Candida lipolytica em água do mar

Silva, Jupiranan Ferreira da 13 May 2015 (has links)
Made available in DSpace on 2017-06-01T18:20:46Z (GMT). No. of bitstreams: 1 jupiranan_ferreira_silva.pdf: 1162753 bytes, checksum: 18468826771d0c312bc9106cfad94a8f (MD5) Previous issue date: 2015-05-13 / Spills of oil and oil products, such as kerosene and diesel in seawater are cause for concern worldwide due to serious effects caused to the marine and coastal environment. The rate of biodegradation of hydrocarbons in sea water is affected by many physical, chemical and biological parameters, including the number and diversity of endogenous microorganism, the conditions for microbial degradation activity (presence of nutrients, oxygen and favorable conditions pH and temperature), the quantity, quality and bioavailability of contaminants and characteristics of sea water. In this work, two 24 full factorial designs were carried out to analyze the influence of pH (6, 10 and 14) and concentrations of kerosene and nutrients (ammonium sulfate and potassium phosphate monobasic) on degradation of kerosene and production bioemulsifiers/biosurfactants by Candida lipolytica UCP 0988 in seawater. The seawater used in the tests was collected near the beach in Suape Harbor, Pernambuco, Brazil. The biodegradation tests were performed at the temperature of 28 ° C, on a rotatory shaker at 200 rpm, for 5 days. The yeast C. lipolytica UCP 0988 was able to use kerosene (10%, 20% or 30% v / v) and grows in seawater, supplemented with ammonium sulfate and potassium phosphate monobasic, producing biosurfactants with high emulsification activity. The phytotoxicity of biodegradated samples collected with 5 days was evaluated using seed germination and root elongation techniques with Makassar beans (Vigna ungiculata (L.) Walp.). / Derramamentos de petróleo e derivados, como querosene e diesel, em água do mar são motivos de preocupação mundial devido aos sérios efeitos causados ao meio ambiente marinho e costeiro. A taxa de biodegradação de hidrocarbonetos em água do mar é afetada por inúmeros parâmetros físico-químicos e biológicos, incluindo o número e a diversidade de micro-organismos endógenos, as condições para a atividade de degradação microbiana (presença de nutrientes, oxigênio favorável e condições de pH e temperatura), a quantidade, a qualidade e a biodisponibilidade dos contaminantes e características da água do mar. Neste trabalho, dois planejamentos fatoriais completos 24 foram realizados para analisar a influencia do pH (6; 10 e 14) e das concentrações de querosene e nutrientes (sulfato de amônio e fosfato monobásico de potássio) sobre degradação de querosene e produção de bioemulsificantes/biossurfactantes por Candida lipolytica UCP 0988 em água do mar. A água do mar usada nos ensaios foi coletada em praia próxima ao Porto de Suape, Pernambuco, Brasil. Os ensaios de biodegradação foram realizados à temperatura de 28ºC, em um agitador rotatório a 200rpm, durante 5 dias. A levedura C. lipolytica UCP 0988 foi capaz de utilizar querosene (10%, 20% ou 30% v/v) e crescer em água do mar, suplementada com sulfato de amônio e fosfato monobásico de potássio, produzindo biossurfactantes com altas atividades de emulsificação. A fitotoxicidade de amostras biodegradadas coletadas com 5 dias foi avaliada usando técnicas de germinação e crescimento radicular de feijões-macáçar (Vigna ungiculata (L.) WALP.)
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Fylogeografie a populační struktura dvou druhů mřenkovitých ryb (Teleostei: Nemacheilidae) z jihovýchodní Asie / Phylogeography and population structure of two loach species (Teleostei: Nemacheilidae) in Southeast Asia

Dvořák, Tomáš January 2018 (has links)
The freshwater fish species Schistura robertsi and Paracanthocobitis zonalternans belong to the family Nemacheilidae, which is distributed across whole Eurasia and with one species in northeast Africa. P. zonalternans occurs in lowland habitats through western Southeast Asia from Central Myanmar until northern Malaysia. The distribution area is of biogeographic interest, because it crosses several known biogeographic barriers, namely the border between Indian and Indochinese freshwater fauna along the Salween River, the Isthmus of Kra, the Krabi - Surat Thani line and the Kangar - Pattani line. In the present study, around 250 specimens of P. zonalternans from 62 localities across the whole distribution area were investigated using genetic (nuclear and mitochondrial sequences), morphologic and geologic data. The genetic data reveal the existence of seven major clades within the analysed material, each of them with a distinct geographic distribution area and only few cases of overlap, but with occurrence of some cases of secondary contact. Divergence time estimations suggested that P. zonalternans is about 18 my old, and a biogeographic analysis located the region of origin in the Tenasserim region (nowadays southern Myanmar). The global sea level fluctuations seem to have had a strong impact on the...
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A técnica de Blue rayon in situ associada ao teste Salmonella/microssoma como estratégia para o monitoramento de águas estuarinas quanto à presença de compostos policíclicos genotóxicos / The Blue rayon technique in situ associated with the Salmonella / microsome test as a strategy for monitoring estuarine waters for the presence of genotoxic polycyclic compounds

Kummrow, Fábio 07 March 2006 (has links)
O estuário de Santos abriga o maior porto da América Latina e um dos maiores complexos industriais do Brasil. Na década de 1970 foi considerado um dos maiores exemplos de degradação ambiental em ambientes costeiros, e apesar da melhora na qualidade ambiental observada nos últimos anos algumas áreas deste estuário apresentam sedimentos ainda altamente contaminados com compostos tóxicos e genotóxicos, especialmente os Hidrocarbonetos Policíclicos Aromáticos (HPA). Operações de dragagem para manutenção das atividades portuárias são necessárias e consequentemente durante este processo pode ocorrer a ressuspensão de contaminantes presentes nesses sedimentos, tornando-os disponíveis novamente na coluna d\'água. Desta forma é interessante ter uma estratégia eficiente e aplicável no monitoramento da qualidade dessas águas. O Blue rayon (BR) é um adsorvente seletivo para compostos policíclicos com três ou mais anéis fundidos em sua molécula e tem sido utilizado com sucesso no monitoramento de HPA e atividade mutagênica em ambientes aquáticos. Este trabalho teve como objetivo padronizar o uso da técnica de Blue rayon in situ ancorado, onde as fibras são fixas a uma distância padronizada dos sedimentos, associada ao teste de Salmonella/microssoma em microssuspensão a ser aplicada no monitoramento das águas desse estuário. Foram selecionados três pontos de amostragem com diferentes características e sedimentos com variados níveis de contaminação. As duas campanhas iniciais foram realizadas com o objetivo de avaliar a eficiência do BR e de escolher a linhagem de Salmonella mais sensível aos compostos mutagênicos possivelmente presentes nos extratos obtidos bem como verificar a presença de HPA. As cinco campanhas posteriores foram realizadas para verificar o comportamento e a eficiência da estratégia previamente definida no monitoramento das águas desse estuário utilizando experimentos de dose resposta. Os resultados obtidos nas duas primeiras campanhas mostraram que as águas do ponto 1, que contém os sedimentos mais contaminados e recebe os efluentes da COSIPA, apresentam maior contaminação por HPA e atividade genotóxica mais elevada que o ponto 2. Também foi possível determinar que a linhagem de Salmonella YG1041 foi a mais sensível para detectar atividade mutagênica tanto no ponto 1 quanto no ponto 2. Nas cinco campanhas subsequentes as maiores potências mutagênicas foram também observadas no ponto 1 com valores máximos de 5.100 e 36.000 revertentes/g de BR para a linhagem YG1041 na ausência e na presença de ativação metabólica (S9) respectivamente. Nos pontos 2 e 3 as potências observadas foram similares entre si, com valores em torno de 1.000 revertentes/g de BR. Com base nos resultados obtidos nas duas etapas deste trabalho pode-se concluir que a o Blue rayon utilizado in situ a uma distância padronizada dos sedimento associado ao teste de Salmonella/microssoma em microssuspensão com a linhagem YG1041 na presença e na ausência de ativação metabólica (S9) é uma ferramenta que pode ser aplicada no monitoramento da qualidade do estuário de Santos. / Santos estuary is the major Latin American harbor and one of the largest industrial complex of Brazil. In the 1970s, it was considered one of the major examples of coastal degradation. Due to enforcement actions the quality of the environment has improved in the last years in relation to the chemical parameters and toxicity but unfortunately the sediment is still contaminated with toxic and genotoxic compounds especially Polycyclic Aromatic Hydrocarbons (PAHs). For the maintenance of the port activities sediment dredging is needed and during this process contaminants resuspension can occur, leading to the contamination of the water column. Therefore it is interesting to have an efficient strategy that can be used for the water quality monitoring of this area. The Blue rayon is a selective adsorbent to polycyclic compounds containing three or more fused rings and has been successfully used in the monitoring of PAHs and mutagenic activity in aquatic environments. The objective of this work was to evaluate a modified blue rayon hanging technique, denominated in this work \"Blue rayon anchored technique\", where the fibers are placed at a fixed distance from the sediment, associated with the Salmonella/microsome microsuspension assay in order to monitor the water quality of Santos estuary. Three sites with different sources and sediment contamination levels were selected in this study. Two initial samplings were performed in order to evaluate the efficiency of the BR modified technique and find the most sensitive strain of Salmonella typhimurium to the mutagens possibly present in the those waters as well as verify the presence of PAHs. Five subsequent samplings were performed to verify the performance and efficiency of the defined strategy in the estuary water quality monitoring using dose response experiments. In the two initial samplings, the water from the site containing the most contaminated sediment and under influence of COSIPA (site 1) presented higher mutagenic activity and higher levels of PAHs. It was also possible to verify the highest sensitivity of the YG1041 strain in the detection of the mutagenic activity in both sites analyzed. In the subsequent five samplings, higher mutagenic potencies were again observed for site 1, reaching 5,100 and 36,000 revertants per gram of BR for the YG1 041 strain in the absence and presence of S9 respectively. Sites 2 and: presented similar potencies, around 1000 revertants per gram of BR. Based on the obtained results we can conclude that the Blue rayon anchored technique associated with the Salmonella/microsome microsuspension assay with the YG1041 strain in the presence and absence of S9 is an suitable tool to monito Santos estuarine waters.

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