Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-11-12T10:02:52Z No. of bitstreams: 0 / Made available in DSpace on 2015-11-12T10:02:52Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-11-12T10:02:52Z No. of bitstreams: 0 / Made available in DSpace on 2015-11-12T10:02:52Z (GMT). No. of bitstreams: 0 / No mundo de hoje, onde o uso da radiação de diversas naturezas está generalizado, a quantificação da energia depositada por essas diferentes radiações se tornou uma atividade de grande importância, principalmente quando a faixa de energia é considerada elevada, estas altas energias de radiação estão presentes, geralmente, em aceleradores de partículas, reatores nucleares e em irradiadores industriais, por exemplo. Este trabalho tem como objetivo medir altas doses de radiação de raios gama, feixes de elétrons e feixes de prótons utilizando duas variedades de um silicato natural (água-marinha e goshenita) e medir altas doses de nêutrons epitérmicos de alta fluência utilizando dosímetros de Fluoreto de Lítio dopados com Mg, Cu e P (MCP). A técnica utilizada para medir a dose absorvida por esses materiais foi a termoluminescência. As irradiações com raios- γ provenientes de fontes de 60Co foram de 100 kGy a 2000 kGy para a água-marinha e de 600 kGy a 2000 kGy para a goshenita, os resultados de intensidade TL vs Dose mostram que a partir de certa dose - 250 kGy e 1234,8 kGy para água-marinha e goshenita, respectivamente - o sinal TL começa a decrescer. Foi observado neste trabalho que, estes materiais quando irradiados com tais doses e posteriormente irradiados com doses baixas de alguns Gys até cerca de 400-500 Gy, o sinal TL decresce regularmente, podendo ser utilizado na dosimetria das radiações nessa faixa de dose. Para a irradiação de feixe de prótons e de feixe de elétrons foram utilizados dosímetros em placa de goshenita e dosímetros de pastilhas de água-marinha, a carga do feixe de prótons vai de 20 a 216 μC e a dose do feixe de elétrons vai de 10 kGy a 70 kGy. As irradiações com nêutrons epitérmicos utilizando LiF: Mg, Cu, P foram realizadas no reator IEA-R1/IPEN com fluências de 1014 a 1017 n/cm² e a quantificação das doses absorvidas foram realizadas utilizando o método UHTR (Ultra High Temperature Ratio). / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

It is well established that converting wastewater, a point-source of pollution, into reclaimed water makes management of nutrients more difficult. Not all service lines measure the volume of reclaimed water used by a customer, and frequently there are no restrictions on the amount of reclaimed water that is used. Nutrients applied in excess have the potential to runoff or leach through soils and contaminate surface and groundwater resources. This research attempted to determine if corresponding surface water quality monitoring sites in reclaimed service areas reflect elevated total nitrogen (TN) and total phosphorous (TP) concentrations. The Joe’s Creek Watershed in Pinellas County, FL is a highly urbanized watershed with one wastewater plant providing tertiary treatment for reclaimed water (Pinellas County Utilities Dept.) and another wastewater plant providing secondary treatment (City of St. Petersburg Water Resources Dept.). This research reviewed concentrations of TN and TP in the reclaimed water effluent for each wastewater treatment plant and at four tributary sites in the Joe’s Creek Watershed. One tributary site, Bonn Creek, is in the tertiary treated service area, another tributary site, Miles Creek, is in the secondary treated service area, and a third tributary, Joe’s Creek, provides two control sites which are both outside of reclaimed service areas. Based on the results of comparisons and statistical analyses of the 6-year period, the TN and TP concentrations of reclaimed water from the City of St. Pete Wastewater Treatment Plant (WWTP) far exceed those of the Pinellas County WWTP. The TN concentration in the reclaimed effluent from St. Pete was nine times higher than that of Pinellas County. The TP concentration was almost five times higher at St. Pete than Pinellas County. The sites within reclaimed service areas had higher concentrations of TN and TP when compared to the control sites for the same period. Miles Creek recorded the highest mean concentrations of TN and TP of the four monitoring sites. Bonn Creek recorded the second highest mean concentrations of TN and TP. Rainfall data were reviewed and results show that several monitoring dates for Miles Creek and Bonn Creek had elevated TN and TP concentrations which coincided with periods of rainfall deficit. These and other results of this research indicate a need to reconsider minimum wastewater treatment levels in urban environments in an effort to reduce nutrient pollution, as well as a need to expand watering restrictions and enforcement, and expand education of consumers about reclaimed water.

Les cellules LGBC (Laser Grooves Buried Contact) ont été inventées et développées par M. GRENN au sein de l'UNSW. Elles présentent des contacts métal/silicium enterrés permettant d'optimiser le contact métal/silicium sans augmenter le taux d'ombrage de la cellule. Dans ce manuscrit nous étudierons toutes les étapes clefs nécessaires à la réalisation de ce type de cellules de façon à les rendre industrialisables. Dans un premier temps nous étudierons la réalisation de tranchées dans le silicium via deux lasers (vert & IR). Les paramètres de ces tranchées seront comparées pour sélectionner les plus adaptées à notre technologie en nous assurant qu'il est possible de réaliser une diffusion thermique dans ces tranchées. Nous développerons ensuite deux techniques pour réaliser des émetteurs sélectifs, par double diffusion et par diffusion à travers une couche de nitrure de silicium. Enfin nous étudierons deux méthodes de dépôt de nickel par voie chimique une électrolytique et un electroless. / LGBC (Laser Grooved Buried Contact) solar cells was invented and developed by M.GREEN at UNSW. Grooved contact allow to reach a good serial resistivity without incresing the shadowing of the solar cell. In this report we will study the different step necessarry to build this kind of photovoltaic cells. Fisrt we will see the impact of laser effects on silicon and the different parameters to adapte red and green laser for grooved contct. The we will study to way to create selective emitter, on by two diffusion and the second one by diffusion throught a silicon nitride layer. Then we will develope two nickel metallisation one electrolytique and one electroless.

Freshwater bodies have been long observed to become browner within the northern hemisphere. This brownification, has made drinking water production difficult, since increased organic content in freshwaters requires higher dosages of chemicals during water treatment.  Changes in land use through increased industrial forestry, decreased sulphur deposition from reduced industrial emissions, changing patterns of hydrological and meteorological parameters resulting from climate change, including recently highlighted increase in iron concentrations have been proposed to explain brownification. Drained peat bogs are man-made source of brownifying substances, capable of causing brownification in the rivers and lakes where the water ends up. This research is aimed at investigating dissolved organic matter, total organic carbon, iron, phosphorous, nitrogen and colour in bog ditches draining into the Storån River and Lake Bolmen in southern Sweden, in order to answer these research questions: (1) What are the differences in the level of water quality parameters, pH, conductivity, temperature, DOM, TOC, total phosphorous, total nitrogen, Fe and colour, between bog ditches and Storån River? And what could be the outcome of Colour absorbance comparison, between bog ditches, Storån and lake Bolmen as a single control sample? (2) Is there any association among the different water quality parameters, pH, conductivity, temperature, DOM, TOC, total phosphorous, total nitrogen, Fe and colour within the bog ditch water? Water samples from bog ditches and their corresponding Storån River locations, were used in the analysis. DOM and flow showed significant differences, after statistical test for difference. Conductivity, DOM, total nitrogen and total phosphorous exhibited significant correlations with pH.  TOC also had a correlation with DOM., while colour correlated and depended strongly on Fe, within the bog ditches. Therefore, the bog ditch has behaved to contribute some amount of the brownification, found in Southern Swedish Lakes and Rivers. This knowledge might be useful in future, for more studies and control of Swedish fresh water brownification.

No description available.

Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii), a keystone species in western Washington, faces threats on plantations across this region from the invasive species Scotch broom (Cytisus scoparius (L.) Link), whose invasions on recently established stands can lead to mortality of Douglas-fir through overtopping. The susceptibility of sites to Scotch broom achieving dominance over Douglas-fir has been demonstrated as highly site dependent, however the site conditions that cause this have not yet been identified. Scotch broom has a demonstrated average maximum height of 3m, thus, after Douglas-fir exceeds this height, its risk of being overtopped is significantly reduced. This thesis strives to identify sites that were at the greatest risk Douglas-fir being overtopped by Scotch broom by first, identifying what factors improved growth of Douglas-fir during the period when they are at the greatest risk, and second, identifying factors that led to Douglas-fir outcompeting Scotch broom on sites they cohabitated. In Chapter 1, we utilized LiDAR scans, Soil Survey Geographic Database characteristics, and management histories to identify conditions that improved growth for Douglas-fir in ages 3-8. Individual tree detection was used to measure Douglas-fir heights, and a correction algorithm for LiDAR measured young Douglas-fir heights was established from field validation data. We identified that young Douglas-fir had improved growth on sites with lower elevation, flatter slopes, and finer textured soils. The factors identified were then transformed into four potential site index models based on mean stand elevation class, Mean stand elevation class and clay class, textural class and slope class, and textural class and Mean stand elevation class. In Chapter 2, we used paired field plots to examine Douglas-fir and Scotch broom competition on 19 sites across western Washington. Each site had 2 plots with only Douglas-fir and 2 plots with Douglas-fir and Scotch broom. Elevation, soil texture, and soil nutrient composition for carbon, nitrogen and available phosphorous were examined for influence on height and growth rate of both species. We identified that Scotch broom presence was negatively related to Douglas-fir height growth and that sites with either higher percentages of silt, lower concentrations of phosphorous, or higher percentages of Carbon were more likely to have growth patterns close to or exceeding Scotch broom. / Master of Science / Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) is a valuable timber species across western Washington that is commonly grown in plantations. In western Washington when Douglas-fir are planted on a site they often face competition from the invasive shrub Scotch broom (Cytisus scoparius (L.) Link). When Scotch broom invasions occur on a recently planted Douglas-fir stands, they can cause death of the trees if Scotch broom plants grow taller than the young Douglas-fir and obstruct their access to light, a process called overtopping. The risk of Douglas-fir being overtopped has been shown to be dependent on location, however what causes a location to be at risk of overtopping is yet unknown. Scotch broom has a demonstrated average maximum height of 3m, thus, after Douglas-fir exceeds this height, its risk of being overtopped is significantly reduced. This study aims to identify sites that were at the greatest risk Douglas-fir being overtopped by Scotch broom by first, identifying what sites generate the best Douglas-fir growth when they are young and at risk of being overtopped, and second, identifying site characteristics led to Scotch broom growing faster than Douglas-fir on sites they both occur on. To identify sites that produced greater young Douglas-fir height growth we used publicly available soil data from the Soil Survey Geographic Database and company management histories to predict tree heights measured through aerial laser scanning (LiDAR). We found that sites with soil textures that had higher percentages of smaller particles, were on lower elevations, and had gentler hillslopes could all produce greater Douglas-fir height growth. When attempting to identify what causes Douglas-fir to be at risk of being overtopped by Scotch broom we used plots with and without Scotch broom on a variety of field sites. This allowed us to not only identify which characteristics of sites where Douglas-fir was being outgrown by Scotch broom, but also identify if Scotch broom was changing how Douglas-fir grew. We found that reductions in Douglas-fir growth were related to Scotch broom being present and that increases in soil silt percentages, decreases in soil phosphorus concentrations, and increases in soil carbon percentages were related to Douglas-fir having height growth closer to or exceeding that of scotch broom.

Utsläpp av orenat spillvatten till de naturliga vattendragen kan ge stora negativa effekter på det akvatiska ekosystemet och på människans hälsa genom exempelvis övergödning, toxisk påverkan på vattenlevande organismer, sjukdomsspridning och antibiotikaresistens. Reningsverk i större tätorter är idag anpassade för att rena spillvatten från kväve och fosfor, men de flesta reningsverk i Sverige saknar kväverening och är i låg grad anpassade för att rena avloppsvattnet från organiska mikroföroreningar. För att minska belastningen på recipienten krävs extra rening, och ett alternativ till mer traditionella reningstekniker är genom system som våtmarker för spillvattenrening, så kallade spillvattenvåtmarker.  Syftet med denna studie är att undersöka reningsfunktionen i spillvattenvåtmarker för att höja kunskapen kring spillvattenvåtmarkers funktion för avskiljning av kväve, fosfor och läkemedelsrester. Genom en datainsamling från befintliga provtagningar, beräknades avskiljningseffektiviten för kväve och fosfor i sju våtmarker och för läkemedel i fem våtmarker. Även ingående och utgående halter av föroreningar analyserades. Efter analys och jämförelse av reningsresultat, togs parametrar som påverkar avskiljningseffektiviten inom och emellan olika våtmarker fram baserat på hur anläggningen och driften ser ut för respektive våtmark. Även en regressionsanalys gjordes.  I spillvattenvåtmarker kan en kväveavskiljning i medeltal mellan 500 och 1600 kg/(ha·år) motsvarande 14 till 64 % och fosforavskiljning mellan 14 och 68 kg/(ha·år) motsvarande mellan 44 och 85 % väntas. I medeltal har kvävehalterna minskat från 20 mg/l till 13 mg/l, och fosforhalter från 0,27 mg/l till 0,13 mg/l. Resultatet av läkemedelsavskiljning delades in i säsonger, där halterna sommartid minskat från 1500 ng/l till 390 ng/l motsvarande 80 %, och vintertid från 500 ng/l till 315 ng/l motsvarande 21 %. Några läkemedelssubstanser med stor avskiljning var Diklofenak, Furosemid, Ibuprofen och Naproxen. Avskiljningen påverkas till stor del av belastning, som varierar mellan våtmarker och tider på året. Andra parametrar som kunde visas påverka avskiljningen är temperatur och syresättning för kväveavskiljning och mängden fosforsläpp, som i sin tur kan undvikas genom en jämn belastning och torrlagda våtmarkssystem, för fosforavskiljning. Kväve- och fosforavskiljning påverkas dessutom av växtlighet. Läkemedelsavskiljnigen gynnas främst av hög temperatur, solinstrålning och växtlighet. Slutligen kunde konstateras att goda förutsättningar finns för vattenrening i våtmarker, under förutsättning att våtmarken planeras och drivs utifrån en processidé om vad man vill att våtmarken ska åstadkomma. / Discharges of pollutants through wastewater into natural waterways may cause major negative effects on the aquatic ecosystem and human health, where nitrogen, phosphorus and pharmaceutical residues are some of the pollutants found in wastewater. Treatment plants in larger urban areas are today built to reduce nitrogen and phosphorus, but most treatment plants in Sweden lack nitrogen removal and are to a low degree adapted to remove organic micro pollutions. To reduce the load on the recipient, additional treatment is required, and an alternative to more traditional treatment techniques is through systems such as constructed wetlands for wastewater treatment.  The purpose of this study is to investigate the function of constructed wetlands for water treatment to increase knowledge about the function of reducing nitrogen, phosphorus and pharmaceutical residues. Through existing monitoring data, the treatment efficiency of nitrogen and phosphorus from seven wetlands and of pharmaceuticals from five wetlands were calculated. Also, incoming and outgoing concentrations of the pollutants were analyzed. After analysis and comparison of treatment results, parameters that affects removal efficiency within and between different wetlands were obtained based on the facility and operation for each wetland. Also, a regression analysis was made.  In a wetland for wastewater treatment, a nitrogen removal between 500 to 1600 kg/(ha·year) (14 to 64 %) and a phosphorus removal between 14 to 68 kg/(ha·year) (44 to 88 %) can be expected. On average, nitrogen concentrations have decreased from 20 mg/l to 13 mg/l, and phosphorus concentrations from 0,27 mg/l to 0,13 mg/l. The result of pharmaceutical removal was divided into seasons, where the concentrations in summer decreased from 1500 ng/l to 390 ng/l corresponding to 80%, and in winter from 500 ng/l to 315 ng/l corresponding to 21%. Pharmaceuticals with greater removal efficiencies were Diclofenac, Furosemide, Ibuprofen and Naproxen. Conclusions that were drawn is that removal is largely influenced by load, which varies between wetlands and seasons. Other parameters that could be proved is temperature and oxygenation for nitrogen removal and the amount of phosphorous released from the sediment, which for example could be avoided through a constant load, for phosphorous removal. Removal of nitrogen and phosphorus is also affected by vegetation. Removal of pharmaceuticals is mainly benefited by high temperature, solar radiation, and vegetation. / <p>Rättelse angående Tot-N Alhagen våtmark finns i bifogad fil.</p>

In waste water, phosphorous (P) can exist in inorganic or organic forms. Depending on the concentration, P can cause eutrophication and severe environmental pollution. Microorganisms have the ability to use and accumulate P, so microorganisms are studied to treat P in waste water in general and wastewater from cassava starch processing plants in particular. Research results show that in the 20 samples of waste water and sludge of the plant has selected three strains of bacteria that can accumulate P in the form of granules in the cell. Among them, SHV22 has the highest P accumulation capacity, reaching 3.05x10-11 mg/cell, P removal efficiency in wastewater from cassava starch processing factory is 82.1%. The strain was identified as Bacillus amyloliquefaciens. / Trong nước thải P có thể tồn tại dưới dạng vô cơ hoặc hữu cơ. Tùy thuộc vào nồng độ, P có thể gây phú dưỡng và ô nhiễm môi trường nghiêm trọng. Vi sinh vật có khả năng sử dụng và tích lũy P, do đó vi sinh vật là đối tượng được nghiên cứu để xử lý P trong nước thải nói chung và nước thải của nhà máy chế biến tinh bột sắn nói riêng. Kết quả nghiên cứu cho thấy, trong 20 mẫu nước và bùn thải của nhà máy đã chọn lựa được 3 chủng vi khuẩn có khả năng tích lũy P dưới dạng hạt trong tế bào. Trong số đó, chủng SHV22 có khả năng tích lũy P cao nhất, đạt tới 3,05x10-11 mg/tế bào, hiệu quả loại bỏ P trong nước thải của nhà máy chế biến tinh bột sắn đạt 82,1%. Chủng đã được định danh là Bacillus amyloliquefaciens.

Microbes, living on the boundary between the sediment and the water-column in lakes, can play a pivotal role in governing the magnitude and frequency of nutrient cycling. The purpose of this research was to focus on the role of benthic microalgae in regulating such processes and to identify spatial and temporal characteristics in their function. Approaches included the quantification of sediment nutrient concentrations (particularly P fractionation), estimates of equilibrium phosphate concentrations (EPC0) (resuspended and undisturbed sediment estimates), and assessment of the benthic microalgal community composition, biostabilisation capacity, and its ability to regulate diffusive-nutrient flux. This thesis highlighted the importance of biological regulation of benthic/pelagic nutrient cycling, especially the role of benthic microautotrophs. Release sensitive sediment-P fractions were observed to be highly variable (both with depth and season) and correlated well with indicators of benthic photosynthesis (e.g. DO, chlorophyll, pH). Understanding the seasonality of whole-system P partitioning can enhance future lake management programmes. EPC0 estimates were significantly higher during undisturbed as opposed to disturbed sediment conditions. Epipelon constituted < 17 % of the total sediment chlorophyll signal and was highest in the clearer winter months and at intermediate depths at which a trade off between wind-induced habitat disturbance and light limitation existed. In intact core experiments, the benthic microalgal community significantly reduced the diffusive nutrient (especially PO₄-P and SiO₂) flux. NH₄ -N release was highest under light conditions at high temperatures. The mechanisms for regulation included direct uptake, photosynthetic oxygenation of the sediment surface, and regulation of nitrification/denitrification processes. Sediment stability increased with colloidal carbohydrate concentration (extruded by benthic microbes) at 4.1 m water-depth but not at 2.1 m overlying water depth, probably indicating the role of habitat disturbance in shallow areas acting to reduce epipelic production. Additionally, in an ecosystem comparison, the nature and extent of the biotic mediation of sediment stability varied between freshwater and estuarine ecosystems.