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A history of Raiwai Fijian settlement.McGrath, Frances Mary. January 1970 (has links) (PDF)
Thesis (B.A.Hons. 1970) from the Dept. of History, University of Adelaide.
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Pluralism and social change in Suva City, FijiMamak, Alexander January 1974 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1974. / Bibliography: leaves 344-350. / xiii, 350 leaves ill., maps
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BIOLOGICAL CONTROL OF UV ATTENUATION: NATURAL SUNSCREEN IN A CHANGING WORLDJordan, Kristen 01 August 2014 (has links)
Chromophoric Dissolved Organic Matter (CDOM) is a substance produced by the planktonic community that naturally blocks biologically damaging, ultraviolet radiation (UV; wavelengths = 280 to 400 nm). While a variety of planktonic species produce CDOM, investigations into the quality and quantity of their CDOM production are few. The purpose of this study was to investigate the properties of CDOM produced by phytoplankton versus zooplankton. Typically, UV radiation breaks down CDOM. However, marine organisms sometimes produce CDOM that, when exposed to sunlight, increases its absorbance of UV radiation. The reasons for this anomaly and the source of this unusual CDOM are unclear. To test for distinctions among sources, filtered water samples from cultures of two marine phytoplankton, Gymnodinium sp. and Dunaliella sp., and a marine copepod, Tigriopus californicus were exposed to sunlight for intervals of 0, 0.5, 1, 2, and 4 hours. The maximal UVB radiation (wavelengths; λ = 280 to 320 nm) was 0.1699 J cm-2. Before and after sunlight exposures, CDOM sources were assessed by comparing absorbance spectra from 184 to 730 nm with detailed comparisons at wavelengths of 254, 305, 320, and 350 nm. Results are expressed as "absorption", which is the raw absorbance converted to the natural log. Before exposure to sunlight, CDOM from algal species had 5- to 8-times higher average absorption values across UV wavelengths than CDOM produced by Tigriopus. CDOM samples produced by phytoplankton were more susceptible to photochemical change than CDOM from Tigriopus. In response to sunlight, CDOM from Gymnodinium varied greatly, increasing in UV absorption in 2 out of 5 replicates but decreasing in absorption in the other replicates. In contrast, peak absorption at λ = 260 nm of CDOM from Dunaliella decreased directionally by an average of 76% in absorption and 75% in specific absorption, and this decrease in absorption was significant (p = 0.03). CDOM from Tigriopus significantly decreased in both absorption (all UV wavelengths, p < 0.01) and "specific absorption", which is absorption standardized per mg of dissolved organic carbon (λ = 320 nm; p < 0.03), but the magnitude of change was only 17%. Thus, photochemical responses of CDOM from the three planktonic sources demonstrated more, consistently less, and unchanged UV absorption. Phytoplankton biomass, which is greater than that of copepods at the next trophic level, likely produce more CDOM but because of greater variability in CDOM absorbance of UV both within and between algal sources, copepods may offer a more stable source of UV protection depending on sunlight exposure and their relative abundance. Definitive conclusions depend on future laboratory studies expanded to more planktonic organisms as well as in situ studies during oceanographic cruises to test the relative contributions of planktonic species.
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Reducering av DOC beroende av karaktär med fyra dricksvattenberedningstekniker : Jämförelse mellan fällning (FeCl3 och Al2(SO4)3), membranfiltrering och jonbyte med MIEX®Nilsson, Sarah, Wängdahl, Sofia January 2014 (has links)
Halten löst organiskt material (DOC) har under de senaste 20 åren ökat i våra sjöar. Det har också skett förändringar i karaktären. DOC ställer till problem för vattenverk som använder ytvatten som dricksvattenkälla genom att det kan ge lukt, smak och färg till vattnet. Det ger också ett ökat behov av fällningskemikalier, större slambildning och större bildning av potentiellt skadliga desinfektionsprodukter. I och med förändringarna i halt och karaktär av DOC behöver nuvarande reningstekniker förbättras och nya tekniker utvecklas. I den här studien undersöktes två konventionella reningstekniker; fällning med järnklorid och fällning med aluminiumsulfat, samt två modernare tekniker; jonbyte med MIEX® och membranteknik. Sex olika vatten med extrema typer av DOC användes, såsom algogent vatten, avloppsvatten och myrvatten, för att få en stor spridning i SUVA (specifik UV254-absorbans). SUVA är kvoten mellan absorbansen vid 254 nm och DOC-halten och ger en indikation på fördelningen mellan alloktont och autoktont material. Analys av DOC, absorbans, fluorescensparametrar, anjoner och järn utfördes för att få en uppfattning av hur mycket och vilken typ av DOC som renades för respektive teknik. Membrantekniken hade generellt högre reducering av DOC än övriga reningstekniker. Genomgående renades alloktont material i högre utsträckning än autoktont material. Vatten med högt SUVA-värde (>3), alltså större andel alloktont material, var mer lättbehandlat än ett med lågt värde, men sambandet var inte linjärt. Algogent vatten renades dåligt med MIEX® och fällning men bättre med membran. Det fanns ett tydligt samband mellan absorbans (245 nm) och DOC-halt som gör det möjligt att med online-mätning av absorbans få fram tillräckligt noggranna värden på DOC-halter. / The amount of dissolved organic carbon (DOC) has risen in our lakes during the past 20 years and it has also changed in character. DOC causes problems for water treatment plants that are using surface water as a drinking water source. It gives the water odour, taste and colour. It also leads to a higher need of precipitation chemicals, more sludging, and larger formation of potentially harmful disinfection products. With the changes in both amount and character in DOC, current water treatment techniques need to be improved and new techniques developed. In this study, two conventional water treatment techniques; precipitation with iron chloride and precipitation with aluminium sulphate, and two more modern techniques; ion exchange with MIEX® and membrane filtration, were examined. Six waters with extreme types of DOC were used, including algogenic water, wastewater, and water from mire, in order to have a wide range of SUVA-values (specific UV254-absorbance). SUVA is the ratio between absorbance at 254 nm and the content of DOC. SUVA gives an indication about the distribution of allochthonous and autochthonous matter. In each water treatment technique analysis of DOC, absorbance, fluorescence parameters, anions, and iron were performed to gather information regarding how much and which type of DOC were reduced, in each water treatment technique. Membrane filtration had generally higher reduction of DOC compared to the other techniques. Allochthonous matter was reduced to a higher extent than autochthonous matter. Waters with a high value of SUVA (>3), which means a larger proportion of allochthonous matter, was more easily treated than water with lower values, but the relation was not linear. DOC in algogenic water was poorly reduced with MIEX® and the precipitation techniques, but better reduced with the membrane filtration. There was a correlation between absorbance (254 nm) and the amount of DOC, which makes it possible to do online reading of absorbance and translate the values into amount of DOC.
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Dynamika rozpustné půdní organické hmoty v závislosti na činnosti mravenců v jehličnatém lese mírného pásma / Dynamics of dissolved organic matter depending on the activity of ants in coniferous temperate forestVacířová, Anna January 2018 (has links)
5 Abstrakt Soil organic matter is the largest reservoir of carbon in terrestrial ecosystems, and its functionally important component is dissolved organic matter. Its composition and changes in this composition during the vegetation season affect the vegetation, the activity of the organisms in the soil and the formation of soil organic matter. Local bio-hotspots such as anthills create spatial heterogeneity of the soil solution composition. In my work I analyzed cold water (CWE) and hot water (HWE) soil extracts, which I took in different distances from the anthill, in three soil horizons (O, A, B) three times during one vegetation season. I measured contents of carbon (C), nitrogen (N), C: N ratio and the parameter SUVA254 and SUVA280. The labile C and N content varied with the distance from the anthill. The C and N content with the distance from the anthill at O horizon increases, decreases in A and B. C: N ratio was the highest in the A horizon, but during the season the differences were not so significant. The smallest content of C and N was in April, the highest in July. The SUVA parameter in O and B decreases with distance from anthill, in A on the other hand it has risen. Ants have an effect not only on the quantity but also on the quality of the DOM, at the same time creating heterogeneity of DOM...
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Methods for reduction of trihalomethanes in the rural municipality of Macdonald potable water supply systemCho, Steven Y. F. 13 January 2010 (has links)
Monitoring data for potable water in the R.M. of Macdonald regional water system indicates elevated levels of chlorine disinfection by-products (DBPs), trihalomethanes (THMs). Dissolved Organic Carbon (DOC) and chlorine dose are the key precursors for the formation of THMs. Currently, the DOC is not removed efficiently at the Sanford water treatment plant, which supplies the R.M.’s potable water distribution system. The raw water DOC concentration incoming to the plant varied from 8.9mg/L to 31.8mg/L during this study. Sanford treated water effluent contained an average DOC of 6.5mg/L and the THM levels ranged from 86.6ppb to 175.7ppb.
One of the objectives of this study was to conduct jar tests to optimize Sanford’s water treatment process to improve removal of DOC. Optimization of the coagulation process successfully reduced the DOC level in the plant effluent by 51% during the summer and 34% in the winter. The DOC reduction resulted in a THM reduction of 73.5ppb in the summer and 59.9ppb during the winter. Results showed that removal of 1mg/L of DOC eliminates 26.8ppb of THMs in summer and 11.9ppb during the winter.
Another goal of this project was to investigate the relationship between THMs and their precursors, which includes: water DOC, free chlorine residual, and the chlorine contact time. Water samples were strategically collected throughout the Sanford regional water distribution system; the samples were tested for DOC, UV254, SUVA, chlorine residual, and contact time. A linear relationship between THM formation and chlorine contact time (R2 of 0.92) was found. This indicates that the content of THMs can be decreased by reducing the amount of time the water stays in the distribution system.
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Methods for reduction of trihalomethanes in the rural municipality of Macdonald potable water supply systemCho, Steven Y. F. 13 January 2010 (has links)
Monitoring data for potable water in the R.M. of Macdonald regional water system indicates elevated levels of chlorine disinfection by-products (DBPs), trihalomethanes (THMs). Dissolved Organic Carbon (DOC) and chlorine dose are the key precursors for the formation of THMs. Currently, the DOC is not removed efficiently at the Sanford water treatment plant, which supplies the R.M.’s potable water distribution system. The raw water DOC concentration incoming to the plant varied from 8.9mg/L to 31.8mg/L during this study. Sanford treated water effluent contained an average DOC of 6.5mg/L and the THM levels ranged from 86.6ppb to 175.7ppb.
One of the objectives of this study was to conduct jar tests to optimize Sanford’s water treatment process to improve removal of DOC. Optimization of the coagulation process successfully reduced the DOC level in the plant effluent by 51% during the summer and 34% in the winter. The DOC reduction resulted in a THM reduction of 73.5ppb in the summer and 59.9ppb during the winter. Results showed that removal of 1mg/L of DOC eliminates 26.8ppb of THMs in summer and 11.9ppb during the winter.
Another goal of this project was to investigate the relationship between THMs and their precursors, which includes: water DOC, free chlorine residual, and the chlorine contact time. Water samples were strategically collected throughout the Sanford regional water distribution system; the samples were tested for DOC, UV254, SUVA, chlorine residual, and contact time. A linear relationship between THM formation and chlorine contact time (R2 of 0.92) was found. This indicates that the content of THMs can be decreased by reducing the amount of time the water stays in the distribution system.
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Disinfection By-products Formation In Low - Bromide And Low - Suva WatersAtes, Nuray 01 May 2008 (has links) (PDF)
The main objective of this study was to conduct a systematic investigation of the disinfection by-products (DBPs) formation in low-bromide and low- specific ultraviolet absorbance (SUVA) waters and the control of DBP precursors by nanofiltration (NF) and ultrafiltration (UF) processes in such waters. To this end, firstly, the effect of bromide ion on the formation and speciation of DBPs was investigated. In fractionated Alibeykö / y source water, increasing bromide concentrations in NOM fractions increased concentrations of trihalomethanes (THMs), haloacetic acids (HAAs) and adsorbable organic halides (AOX) and resulted in a shift toward the formation of brominated species. Secondly, the impacts of SUVA and differential UV spectroscopy (& / #916 / UV), which has been shown to correlate well with DBP formation has been elucidated in terms of DBP formation and speciation. Alibeykö / y and Karacaö / ren waters were fractionated employing various separation methods and it has been shown that SUVA did not correlate well with the formation and speciation of THMs and HAAs in tested low-SUVA waters. Similarly, no correlations were found among THMs/HAAs formations and & / #916 / UV. Finally, the NOM rejection performances of NF and UF membranes were investigated. NF and UF membranes (< / 2000 dalton) was found to be suitable for the removal NOM from surface waters having low SUVA and low bromide contents. While higher molecular weight (HMW) fraction was successfully rejected (> / 90%) by all membrane types, lower molecular weight (LMW) fraction could be removed with ranging efficiencies from 1.5 to 30%. NF membranes provided DOC, UV254 absorbance, THM, and HAA reductions up to 90%.
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Uticaj različitih tehnoloških parametara na formiranje boje tradicionalne fermentisane kobasice (Petrovačka kobasica) tokom standardizacije bezbednosti i kvaliteta / The influence of different technological parameters during standardization of safety and quality on the color formation of traditional fermented sausage (Petrovačka kobasica)Škaljac Snežana 22 December 2014 (has links)
<p>Zadatak ove doktorske disertacije je bio da se utvrdi uticaj različitih tehnoloških parametara na formiranje boje Petrovačke kobasice, kao i da se modelovanjem tradicionalne tehnologije utvrdi zavisnost između brojnih tehnoloških parametara i optimalnog kvaliteta boje ovog tradicionalnog proizvoda, radi standardizacije kvaliteta i bezbednosti, a u cilju dobijanja prepoznatljivog proizvoda vrhunskog kvaliteta koji bi se kontinuirano proizvodio.<br />U cilju realizacije postavljenih zadataka tokom tri proizvodne sezone je izrađeno 13 modela Petrovačke kobasice kako bi se ispitao uticaj sledećih varijabilnih tehnoloških parametara: proizvodne sezone, vremena otkoštavanja mesa post mortem, vrste upotrebljenog omotača (prirodni i veštački), ručnog i mašinskog mešanja, dimljenja u tradicionalnim i kontrolisanim uslovima, sušenja i zrenja u tradicionalnim i kontrolisanim uslovima, dodatka izolovane autohtone starter kulture, vremena skladištenja i načina pakovanja (neupakovane, pakovane u vakuumu i modifikovanoj atmosferi) na proces formiranja boje.<br />Formiranje boje Petrovačke kobasice tokom procesa dimljenja, sušenja i skladištenja praćeno je određivanjem instrumentalnih pokazatelja boje (L*, a*, b*, h, C*, R, BI i ΔE) na površini i preseku Petrovačkih kobasica. Utvrđeni su brojni tehnološki parametri (vrednost pH, sadržaj vlage, sadržaj ukupnih masti, sadržaj ukupnog pepela i sadržaj hlorida), pokazatelji senzornog kvaliteta (spoljašnji izgled i stanje omotača, boja i održivost boje na preseku, ukupan senzorni kvalitet) i kvalitet ljute začinske paprike. Analizom rezultata dobijenih u ovim ispitivanjima zaključeno je da su kobasice izrađene od ohlađenog mesa dimljene i sušene u tradicionalnim uslovima (B1 i B2 grupe) imale optimalan kvalitet boje i bile vrhunskog (zaštićenog) senzornog kvaliteta. Niže temperature (8,30°C-10,7°C) tokom procesa dimljenja i sušenja, sporiji pad vrednosti pH, od 5,69 (nadev) do ~5,4 (na kraju procesa fermentacije) i sadržaj hlorida ~ 3% u gotovom proizvodu, uz dodatak kvalitetne ljute začinske paprike omogućili su formiranje optimalne boje ove grupe kobasica. Optimalnu boju preseka kobasica karakterišu numerički manje vrednosti instrumentalnih pokazatelja boje (L*, a*, b*, h, C* i BI) u odnosu na kobasice sa nižim senzornim ocenama za boju. Tokom skladištenja (od kraja sušenja do 270. dana proizvodnje) utvrđene su manje promene instrumentalnih pokazatelja boje na površini i preseku Petrovačkih kobasica kada su skladištene upakovane (vakuum i modifikovana atmosfera) u poređenju sa neupakovanim. Pakovanje u vakuumu i modifikovanoj atmosferi je dobro rešenje za očuvanje optimalnih karakteristika boje kobasica, jer su upakovane kobasice B1 i B2 grupe skladištene 4 meseca od završetka procesa sušenja (od 90. do 210. dana od dana proizvodnje) bez promena senzornog kvaliteta boje, a zatim su do kraja perioda skladištenja (270. dana proizvodnje) promene bile neznatne.<br />Uzimajuću u obzir da su ova istraživanja deo šire koncipitranih istraživanja razvoja tradicionalne tehnologije proizvodnje Petrovačke kobasice i standardizacije kvaliteta i bezbednosti, ispitan je uticaj varijabilnih tehnoloških parametara i na formiranje policikličnih aromatičnih ugljovodonika u Petrovačkoj kobasici, kao veoma važnih pokazatelja zdravstvene bezbednosti kobasica.<br />Jedan od najznačajnijih rezultata u ovim istraživanjima je da benzo[a]piren nije detektovan ni u jednom uzorku Petrovačke kobasice. Takođe je zaključeno da je Petrovačka kobasica dimljena na tradicionalan način, kao i u industrijskim uslovima bezbedna za potrošače sa aspekta sadržaja policikličnih aromatičnih ugljovodonika, jer su svi ispitani uzorci kobasica ispunjavali uslove propisane domaćim i evropskim propisima.</p> / <p>The aim of this Ph.D. dissertation was to determine the influence of various technological parameters on the colour formation of Petrovačka kobasica, as well as to define correlation between number of technological parameters and optimal colour quality of traditional product (by modelling traditional technology), in order to standardize quality and safety, and consequently with the main goal to obtain a recognizable high quality product that could be continuously produced throughout the whole year period.<br />To achieve the defined tasks in three production season 13 models of Petrovačka kobasica were produced in order to examine the effect of the following variable technological parameters: production season, post mortem time of meat deboning, type of the casing (natural and artificial), manual or mechanical mixing, smoking in traditional and controlled conditions, drying and ripening in traditional and controlled conditions, the addition of isolated indigenous starter culture, and storage time and packaging (unwrapped, packed in vacuum and modified atmosphere) in the process of colour formation.<br />Colour formation of Petrovačka kobasica during smoking and drying processes and storage was followed by determination of instrumental colour parameters (L*, a*, b*, h, C*, R, BI and ΔE) on the surface and cut cross section of Petrovačka kobasica. The number of technological parameters (pH, content of moisture, total fat, total ash and chloride), indicators of sensory quality (sausage appearance and condition of casing, colour and colour stability at the cut cross section, the overall sensory quality) and quality of red hot paprika powder were determined. Analysing the results obtained in these studies it was concluded that sausages produced from chilled meat and smoked in traditional conditions (sausages of B1 and B2 groups) had the optimal colour quality and superior (protected) sensory quality. Lower temperatures (8.30°C-10.7°C) during smoking and drying processes, slower decrease of pH value from 5.69 (raw sausage after stuffing) to ~ 5.4 (at the end of the fermentation process) and the chloride content ~ 3% in the final product, with the addition of high quality red hot paprika powder enable the formation of the optimal colour of these groups of sausages. Optimal colour of cut cross section of sausages was characterized with numerically smaller values of instrumental colour parameters (L*, a*, b*, h, C* and BI) in relation to sausages with lower scores for sensory evaluated colour. During storage (from the end of drying process up to 270 days of production), minor changes of instrumental colour characteristics on the surface and cut cross section of Petrovačka kobasica were noted when sausages were stored packed in vacuum or modified atmosphere, compared with unpackaged ones. Packing in vacuum and modified atmosphere is a good solution for the preservation of optimal colour characteristics, as packaged sausages of B1 and B2 groups stored for 4 months from the end of the drying process (from 90 to 210 days from the date of production) had no changes in sensory evaluated colour quality. Further, until the end of storage (270 days of production) just minor changes of this sensory parameter were noticed.<br />Considering that these investigations are a part of wider conceived researches of development of traditional technology of Petrovačka kobasica and standardization of quality and safety, the influence of variable technological parameters on the formation of polycyclic aromatic hydrocarbons in Petrovačka kobasica, as a very important indicator of health safety of sausage, were also studied.<br />One of the most important results of these researches is that benzo[a]pyrene was not detected in any sample of Petrovačka kobasica. It was also concluded that Petrovačka kobasica smoked in traditional way, as well as in industrial conditions was safe for consumers in the terms of the content of polycyclic aromatic hydrocarbons, as all samples of analysed sausages meet the requirements defined by national and European regulations.</p>
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Spectroscopic characterisation of dissolved organic matter changes in drinking water treatment: From PARAFAC analysis to online monitoring wavelengthsShutova, Y., Baker, A., Bridgeman, John, Henderson, R.K. 07 February 2014 (has links)
No / Organic matter (OM) causes many problems in drinking water treatment. It is difficult to monitor OM concentrations and character during treatment processes due to its complexity. Fluorescence spectroscopy is a promising tool for online monitoring. In this study, a unique dataset of fluorescence excitation emission matrixes (EEMs) (n = 867) was collected from all treatment stages of five drinking water treatment plants (WTPs) situated in diverse locations from subtropical to temperate climate. The WTPs incorporated various water sources, treatment processes and OM removal efficiencies (DOC removal 0%–68%). Despite these differences, four common fluorescence PARAFAC components were identified for characterisation of OM concentration and treatability. Moreover, fluorescence component ratios showed site-specific statistically significant correlations with OM removal, which contrasted with correlations between specific UV absorbance at 254 nm (SUVA) and OM removal that were not statistically significant. This indicates that use of fluorescence spectroscopy may be a more robust alternative for predicting DOC removal than UV spectroscopy. Based on the identified fluorescence components, four optical locations were selected in order to move towards single wavelength online OM monitoring.
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