Tesi: "Green water"

1

Han, Juchull. "Impact of green water on FPSOs". Thesis, University of Newcastle Upon Tyne, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275418.

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2

Greco, Marilena. "A Two-Dimensional Study of Green-Water Loading". Doctoral thesis, Norwegian University of Science and Technology, Faculty of Engineering Science and Technology, 2001. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-524.

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Large relative motions between the ship and the water may cause water shipping on the main deck. In this thesis, the fundamental features of water-on-deck phenomena are in vestigated, together with the "green" water loading on a deck house in the bow region. The studies are relevant for a stationary ship like a FPSO in head sea waves.

Potential flow theory is used to study numerically a nonlinear two-dimensional problem in a plane containing the ship's centerplane. The developed model is verified by various test cases, and validated by published as well as new experimental data.

The influence of wave parameters, ship motions and hull geometry is investigated. Relevance of three-dimensional effects is discussed.

Dedicated two-dimensional model tests have been performed, both to elucidate the fluid mechanics involved in the water shipping and to validate the numerical method. It is found that the water shipping starts in the form of a plunging wave hitting the deck. This could cause structural damages. Most often, the plunging is localized in the bow region and do not affect the main flow at a later stage. In a few cases, larger masses of water bluntly impacting with the deck have been observed. The latter is consistent with seldom observations reported in 3-D experiments, with large and steep waves plunging directly onto the deck. More often the water flow along the deck resembles the one subsequent to a dam breaking. Both types of events are investigated numerically. The impact pressures on a vertical wall in the bow area are measured and compare well with the boundary element method.

The reliability of a dam-breaking model and shallow-water approximation to study the propagation of water on the deck is examined. The former can only qualitatively describe the flow evolution.The latter can in principle be used but needs information from the exterior flow and, thus, the solution of the complete ship-waveinteraction problem.

Water impacts with a deck house in the bow area are studied in details. Use of a similarity solution for a water wedge hitting a rigid wall at 90º is compared with the fully numerical solution. The method predicts correctly the first stages of the impact with a smaller computational effort. Inuence of local flow conditions and wall slope on hydrodynamic loads is discussed. Importance of hydroelasticity is investigated in case of realistic structural parameters for the deck house. This shows a limited role of structural deformations in determining the maximum loads.

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3

Pham, Xuan Phuc. "Green water and loading on high speed containerships". Thesis, Connect to e-thesis, 2008. http://theses.gla.ac.uk/249/.

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Thesis (Ph.D.) - University of Glasgow, 2008.
Ph.D. thesis submitted to the Department of Naval Architecture and Marine Engineering, Faculty of Engineering, University of Glasgow, 2008. Includes bibliographical references. Print copy also available.

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4

Abel, Heiko. "Frigate defense effectiveness in asymmetrical green water engagements". Thesis, Monterey, California : Naval Postgraduate School, 2009. http://handle.dtic.mil/100.2/ADA508855.

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Thesis (M.S. in Modeling, Virtual Environments and Simulation (MOVES))--Naval Postgraduate School, September 2009.
Thesis Advisor(s): Sanchez, Paul J. ; Second Reader: Kline, Jeffrey E. "September 2009." Author(s) subject terms: Agent Based Simulation, Asymmetric Warfare, Data Farming, Design of Experiments, Evolving Design, MANA, Modeling and Simulation, Naval Swarm Defense, Robust Design, Regression Analysis, Simulation Experiments and Efficient Design Center, Taguchi Method Description based on title screen as viewed on November 03, 2009. DTIC Descriptor (s): Frigates, Theater Level Operations, Defense Systems, Experimental Design, Confined Environments, Asymmetry, Statistical Analysis, Sea Water, Small Ships, Threats, Survivability, Weapons, Theses DTIC Identifier (s): SSTR (Stability Security Transition and Reconstruction), Asymmetric Warfare, Mana Includes bibliographical references (p. 125-132). Also available in print.

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5

Joustra, Caryssa. "An Integrated Building Water Management Model for Green Building". Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3654.

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The U.S. Green Building Council (USGBC) is the developer of the Leadership in Energy and Environmental Design (LEED™) green building scoring system. On first inspection of LEED points, few address water efficiency. However, water management encompasses other points beyond the Water Efficiency (WE) category. In general, the industry is apt to take a somewhat compartmentalized approach to water management. The use of alternative water sources or the reuse of wastewater significantly complicates the water budget picture. A total water management systems approach, taking into consideration water from various sources, both inside and outside the building, should be implemented in order to devise a strategy for optimal reduction of potable water consumption and wastewater generation. Using the STELLA software to create an integrated building water management (IBWM) model provides stakeholders with a tool to evaluate potential water savings under dynamic conditions for a specific project site. Data collection for IBWM model calibration also shows that water consumption trends are unique to each project, and using LEED assumptions about water usage can overestimate or underestimate potential water savings.

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6

Schuchman, Rachel. "Storm Water Retention of Native and Sedum Green Roofs". Thesis, Southern Illinois University at Edwardsville, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10111534.

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Green roofs are an established best management practice (BMP) for storm water mitigation because of their ability to retain precipitation runoff. The purpose of this study was to quantify storm water retention of Sedum and native plant green roof systems at three substrate depths (10, 15, 20 cm). Survival of plants on green roof systems is dependent on how quickly they can establish themselves. This study also determined native and Sedum plant roof surface coverage at three green roof growth media depths (10, 15, 20 cm). A mixture of six Sedum species (S. spurium, S. sexangulare, S. album, S. Immergrunchen, S. kamtschaticum, and S. reflexum) and four native species (Sporolus cryplandrus, Boutelous curtipendula, B. gracilis , and Penstamen pallidus) were planted into the built-in-place systems (BIPs) on June 20, 2014.

There were 137 precipitation events totaling to 158.2 cm during the entire (June 20, 2014-June 30, 2015) study period and there were 87 precipitation events with a total precipitation of 108.1 cm during storm water collection (Oct. 31, 2015 until June 30, 2015). During the study period, mean storm water retention of green roof systems planted with native (>58%) and Sedum (>53%) species were identical regardless of growth media depth. Mean storm water retention in green roof systems planted with native and Sedum species in all growth media depths were greater than mean storm water retention of non-vegetated roof models (32%).

Green roof plant surface coverage plays an important role in water retention of storm water runoff. During the dormant period (January 23, 2015), roof coverage by Sedum plants was greater than roof coverage by native plants. In addition, green roof surface coverage by Sedum plants was the same regardless of depth (>89%). Green roof surface coverage of native plants in 10 cm depth achieved less coverage than native plants in 15 and 20 cm depths. These results differ from the plant-growing season (June 30, 2015). Green roof surface coverage by native plants in green roof systems with 15 and 20 cm growth media depth were identical to the roof coverage by Sedum plants in green roof systems with 10, 15, or 20 growth media depth. Green roof surface coverage by native plants in green roof systems with 10 cm growth media depth was less than the roof coverage in all green roof systems in this study.

Analysis of covariance was used to determine if green roof surface coverage by native and Sedum plants affected mean storm water retention. During the study period green roof surface coverage by native and Sedum plants did not affect storm water retention regardless of growth media depth.

This green roof research demonstrates that green roof systems planted with native plant species are effective tools for retaining storm water in the mid-western region of the United States. After 9 months, there was no difference in storm water retention between native and Sedum species planted in 10, 15, and 20 cm growth media depth. Each green roof module retained more storm water than the traditional, non-vegetated roof model. Both native and Sedum species planted on green roofs in 10, 15, and 20 cm media depth achieved more than 69 percent green roof surface coverage after nine months.

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7

Eriksson, Anders Olof. "Water Runoff Properties for Expanded Clay LWA in Green Roofs". Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bygg, anlegg og transport, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-23326.

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A lightweight aggregate (LWA) is a material that has a lower density than rock aggregates. There are many civil engineering application possibilities for LWA. A potential field of application for expanded clay LWA is as a storm water retaining layer in green roofs. In order to design reliable structures of green roofs, more knowledge about the characteristics of the material is needed. The purpose of this master thesis was to test if the software SEEP/W is an appropriate tool for simulation of water runoff from a green roof, designed with expanded clay LWA. The numerical modeling was not performed for all types of expanded clay LWA, but on crushed Leca® 4-10mm and round 10-20mm alone. To test if SEEP/W is advisable tool for simulating water flow in expanded clay LWA, a back calculation of a laboratory experiment was done. The purpose of back calculating the experiment is to calibrate a numerical model and then use it for a full scale ideal roof. Thereafter a sensitivity analysis of the SEEP/W input parameters was performed. It was possible to back calculate the laboratory experiment, meaning obtaining the same relation between water going in and water going out of the tested Leca® material. However, a lot of numerical problems occurred in the simulations. Unrealistic results were displayed, especially for Leca® 10-20mmR. In order to improve the performance of the material, and thereby obtain better water retaining characteristic, a suggestion is to increase the porosity and lower the saturated hydraulic conductivity for the expanded clay LWA materials in order to obtain a higher attenuation.

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8

Beauchamp, Pierre. "Water-centric approach to developing green infrastructure (framework and cost)". Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123225.

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WATER-CENTRIC APPROACH TO DEVELOPING GREEN INFRASTRUCTURE: Framework and CostPierre Beauchamp, P. Eng., 15 avril 2014AbstractGreen infrastructure (GI) has emerged as an active term of reference in project development planning. However, elaboration and discussion of integrated frameworks to assist engineering organizations in planning the start-up of new projects are largely absent from GI research literature, particularly in the context of greening and sustainability. The present study attempts to bridge this gap by developing and proposing an integrated framework focused on the start-up development of green projects relating to storm water, water supply, and wastewater.The present study's first objective was to explore the use of fully integrated GI in the engineering design of a biophilic development incorporating sustainability principles. To achieve the desired teamwork, a clear sequence of tasks to define the workflow was required. A review of the literature led to the identification of several different approaches, from which I selected four, improved, and then employed them to build a ready-to-use framework of sequenced tasks. These tasks included all components of water management (precipitation and drainage, water supply and wastewater). A case study in China employed in testing this framework demonstrated that all GI components could be integrated into one approach. While the structuring of an integrated water-centric development (IWCD) approach was found to be applicable to a wide range of projects, appropriate capacity building was critical to its success.In support of the study's second objective, the newly proposed framework was implemented to compare, in the form of a feasibility study, the economic benefits of investment and overall cost of designing green with those of designing conventionally in the case of a new institutional pole for the city of Vaudreuil-Dorion, Quebec, Canada. While the study showed increases in the value of GI projects to mirror the construction costs of such projects, it also found that implementing GI (vs. conventional) infrastructure can result in savings in both construction and life cycle costs. Therefore, GI can provide significant economic benefits to cities.The study showed that a GI project including components from water source to wastewater disposal would cost 15 percent more, at the level of each housing unit, than a conventional infrastructure design. However, the study also demonstrated that the value of each housing unit would be 15 to 27 percent greater in a green neighborhood than in a conventionally designed neighborhood. This would provide an equivalent increase in tax revenues for the municipality. Although many frameworks have been proposed for stimulating a green urban agenda, few have offered a start-up methodology for incorporating biophilia within the engineer's design. This study served to develop a new integrated framework for storm water, wastewater, water supply, and street layout for GI projects.
WATER-CENTRIC APPROACH TO DEVELOPING GREEN INFRASTRUCTURE: Framework and CostPierre Beauchamp, ing. 15 avril 2014RésuméLe thème des infrastructures vertes (GI) est devenu un terme de référence dans la planification du développement des projets. Toutefois, les approches intégrées pour aider les organisations d'ingénierie dans la planification de la mise en place de nouveaux projets verts sont largement absents de la littérature, en particulier dans le contexte du développement durable. La présente étude vise à combler cette lacune en développant et en proposant une approche axée sur le développement d'une structure de démarrage des projets verts, et en tenant compte du drainage, de l'approvisionnement en eau et du traitement des eaux-usées.Le premier objectif de la présente étude est d'explorer l'utilisation des infrastructures vertes pleinement intégrées dans la conception technique d'un développement durable et dans le contexte d'un développement biophile d'une ville. Pour supporter un travail d'équipe, l'élaboration d'une séquence claire des tâches à exécuter a été nécessaire. Une revue de la littérature a conduit à l'identification de plusieurs approches différentes, à partir de laquelle quatre propositions ont été retenues. De là une approche améliorée, a été conçue pour définir les tâches séquentielles permettant de démarrer un projet vert. Ces tâches comprennent toutes les composantes de la gestion de l'eau (drainage, approvisionnement en eau et eaux-usées). Une étude de cas en Chine a permis de vérifier l'acuité de cette approche. Cette étude a permis de démontrer que toutes les composantes de l'infrastructure verte pourraient être intégrées dans un nouveau projet de développement. Cette approche est nettement centrée sur l'eau.Pour satisfaire un deuxième objectif de l'étude, la nouvelle approche proposée a été utilisée pour comparer, dans le cadre d'une étude de faisabilité, les avantages économiques d'un investissement vert avec celle d'une conception classique, pour l'élaboration du concept d'un nouveau pôle institutionnel de la ville de Vaudreuil- Dorion PQ, Canada. Bien que l'étude ait montré que le coût de construction des projets verts était plus élevé, il a été constaté que sur un cycle de vie les infrastructures vertes peuvent entrainer des économies d'entretien. Les infrastructures vertes peuvent apporter des avantages économiques importants pour les villes.L'étude a démontré que les coûts d'immobilisation des infrastructures vertes étaient de 15% supérieures à comparer à des infrastructures conventionnelles sur la base d'une unité de logement. Par contre, l'étude a également démontré que la valeur de chaque unité d'habitation serait de 15 à 27 pour cent plus élevée dans un quartier vert plutôt que dans un quartier de conception conventionnelle. Cela permet une augmentation équivalente des recettes fiscales pour une municipalité.Bien que de nombreuses approches ont été identifiées, peu d'entre elles permettre de démarrer un projet d'ingénierie biophile. Cette étude a permis d'élaborer une nouvelle approche intégrée pour la mise en place d'infrastructures vertes qui tient compte de la place de l'eau dans le développement.

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9

Yu, Kai. "Level-set RANS method for sloshing and green water simulations". [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2097.

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10

Waern, Sandra. "Microalgae : A Green Purification of Reject Water for Biogas Production". Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-135549.

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Microalgae are a diverse group of unicellular microorganisms found in various environments, ranging from small garden ponds to lakes with extreme salinity. Common for all microalgae is their ability to convert solar energy and carbon dioxide into chemical energy via photosynthesis. Additionally, they are capable of assimilating large amounts of nitrogen and phosphorus to produce proteins and lipids. These abilities have made microalgae an interesting candidate for next generation wastewater treatment coupled with production of biogas, a renewable energy source in advancement. At the Nykvarn wastewater treatment plant in Linköping, Sweden, 15,400,000 m3 of wastewater are treated annually to remove nitrogen and phosphorus that otherwise would risk to cause eutrophication in surrounding lakes and rivers. Moreover, the treatment plant manages large amounts of sewage sludge that is anaerobically digested to produce biogas and simultaneously reduce the sludge volumes. At the Nykvarn wastewater treatment plant, dewatering of the digested sludge results in a sludge fraction of about 30 % dry content and reject water, which is very nutrient-rich and therefore requires treatment in a SHARON process before it is reintroduced to the main stream of the wastewater treatment plant. In this thesis, the potential of microalgae for nutrient assimilation was studied by monitoring the nutrient removal efficiency of a mixed culture of microalgae when fed with 1) 100 % incoming wastewater, 2) 80 % incoming wastewater + 20 % reject water and 3) 60 % incoming wastewater + 40 % reject water. Furthermore, the effect of a process additive on the nutrient removal efficiency was evaluated. The results showed that microalgae are capable of removing 100 % of ingoing ammonium nitrogen and phosphate phosphorus when fed with incoming wastewater. At transition to 20 % and 40 % reject water, the culture was light-limited with a resulting ammonium reduction of 60 % and a phosphate reduction of around 30 %. The process additive slightly improved the ammonium reduction, however, mainly by formation of nitrite and nitrate by nitrifying bacteria. Moreover, a bio-methane potential test compared the methane potential of the microalgal biomass and the biomass from the SHARON process. The test resulted in an accumulated methane production around 70 mL g-1 VS-1 for the microalgal biomass and 35 mL g-1 VS-1 for the biomass from the SHARON process. That is, the mixed microalgal culture used in this experiment has a methane potential twice that of the biomass from the SHARON process. Finally, an economic analysis of a microalgae based process for purification of reject water showed that the operating costs exceed those of the SHARON process due to high energy consumption. It is thus necessary to choose a cultivation system that effectively utilize the solar energy, as well as maximize the biogas yield from anaerobic digestion of microalgal biomass.

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Rujner, Hendrik. "Green Urban Drainage Infrastructure : Hydrology and Modelling of Grass Swales". Licentiate thesis, Luleå tekniska universitet, Arkitektur och vatten, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-67325.

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The management of urban runoff has evolved along with the advancement of understanding of runoff environmental impacts. Besides the impacts on water quality in the receiving waters, the impacts on the urban hydrologic regime include reduced infiltration by the sealing of pervious land, reduced evapotranspiration by removal of vegetation, and the resulting increase of stormwater runoff peaks and volumes causing flooding, and ultimately degradation of receiving waters. In such considerations, urban stormwater management benefits from the implementation of Green Infrastructure which includes decentralized vegetative controls that capture and infiltrates rain where it falls and thus reduces and improves stormwater runoff. An example of small scale elements of Green Infrastructure are traditional grass swales. Through shallow depressions with mild side slopes grass swales collect and infiltrate stormwater from parking lots and roads, while runoff flows are attenuated and further conveyed depending on the hydraulic loading. Grass swales usually operate reliably and their maintenance needs are well understood. Their hydrological performance is, beside their dimensions and the contributing area, determined mainly by hydraulic and soil-related hydrological parameters that change with the intensity of the storm. Yet, because swales discharge to downstream drainage elements, either to the conventional sewer system or to other stormwater management facilities, the knowledge of the underlying inter-related processes and influential factors that govern the hydraulic and hydrological performance of grass swales is required. Against this background, this thesis is devoted to such questions as (i) what are the differences in the hydraulic and hydrological performance of the studied swales, (ii) how do soil characteristics, including the antecedent soil moisture, influence the swale water balance for various hydraulic loadings; and (iii) how can the related hydrological processes be simulated in high-resolution and reliably predicted using a grid-based, distributed model. For this purpose, full-scale studies were performed in three 30-m grass swale sections in Luleå, Northern Sweden, by collecting hydraulic and hydrological data based on routine storm events mimicking block-rainfall storm events of 2 months and 3 years recurrence. The resulting runoff and soil moisture data were used to calculate the swale water balance, to derive event hydrographs and to obtain calibration and validation data for model simulations. The experimental results showed that the relative swale flow volume reduction decreased with an increasing soil moisture and indicated the transition in dominating swale functions: at low initial SWC, runoff was highly attenuated (up to 74%), but for high SWC, the conveyance function dominated (with attenuation as low as 17%). Runoff flow peaks were reduced, proportionally to the volume reductions. Swale outflow hydrograph lag times varied between 5 to 15 minutes and decreased with increasing soil moisture. The swale wetness affected runoff formation, attenuation and subsequent outlet discharge and, for the short-duration events tested, only the top soil layer contributed to these findings. In the three swales tested, soils, initial soil water content, saturated hydraulic conductivity and topography varied spatially significantly. Double-ring infiltrometer measurements resulted in values of 1.78, 4.04 and 9.41 cm/hr (n=9) in the three swales tested and deviated from estimates from averages of spatially integrated infiltration rates. However, with regard to spatial variability, only the topography, described as irregularities in the swale bottom slopes affected the swale runoff dissipation and conveyance in the early phase of the events. Together with estimates of the water stored in the top soil layer, 4-32% of runoff volumes from the mimicked 2-month storm were temporarily stored. The distributed model Mike SHE was found capable of simulating swale drainage processes, when properly calibrated. Close agreement (NSE>0.8) was found not only for the measured and simulated swale outlet hydrographs, but also for the changes of the soil moisture in the top soil layer, which shows rapid increase up to the saturated soil water content, but minor or no progression in depths of 0.2 m. The model output was little sensitive to the initial soil water content, especially for low inflow which resulted in larger residuals in simulated runoff peak flows and volumes. As in field measurements, spatial variability of the initial soil water content had no effect on the swale outflow, but the accuracy of the topographical representation. The thesis findings include several implications regarding effects of the assessed parameters in the application of the model for swale flow simulation and eventually the design of grass swales.
Urban dagvattenhantering har utvecklats parallellt med en ökad förståelse för dagvattnets allmänna miljöpåverkan. Utöver ytvattenkvalitén i recipientvatten påverkas även den hydrologiska regimen genom reducerad infiltrationsförmåga i mark orsakad av allt tätare ytskikt samt reducerad evapotranspiration orsakad av minskad vegetationsutbredning. Detta ger både förhöjda toppflöden och avrinningsvolymer, vilket kan resultera i översvämning och slutligen en försämrad ytvattenkvalité i recipienterna. Dagens urbana dagvattensystem förändras mot en högre grad av grön infrastruktur som en central systemkomponent. Decentraliserad omhändertagning av dagvatten såsom svackdiken utjämnar och för bort dagvattensflöden, samtidigt som de fungerar tillförlitligt och deras underhållsåtgärder är välkända. Uppbyggda med små svackor och låglutande slänter samlar svackdiken in och infiltrerar dagvatten från parkeringsytor och vägar. Dessa svackdikens hydrologiska funktion bestäms av en rad faktorer, utöver teknisk dimensionering och avrinningsområdets storlek och hydrologi, även av hydraulik och jordartsrelaterad hydrologi som förändras beroende på respektive nederbördstillfälles intensitet och varaktighet. Eftersom svackdikens utflöde passerar nedströms liggande dagvattentekniker/anordningar, antingen konventionella ledningssystem eller andra teknologier, krävs full förståelse och kunskap om de faktorer som styr svackdikens hydraulik och hydrologi. Mot denna bakgrund fokuserar avhandlingen på frågorna (i) vilka skillnader finns med avseende på hydraulisk och hydrologisk prestanda för de studerade svackdiken, (ii) i vilken mån påverkar markartsförhållanden, inklusive ingående markfuktighet, svackdikens vattenbalans vid varierande hydraulisk belastning; samt (iii) hur och i vilken mån kan ovanstående simuleras högupplöst och förutsägbart, via den rutnätsbaserade distribuerade modellen Mike SHE. Därför har fullskaliga studier bedrivits i två 30 m långa svackdiken i Luleå kommuns södra stadsområde, där hydrauliska och hydrologiska data insamlats baserat på standardiserade nederbördsförlopp, återskapande blockregn med 2 månaders och 3 års återkomsttid. Data för avrinning och markfukthalter användes för att beräkna svackdikenas vattenbalans, nederbördförloppens hydrografer samt erhålla kalibrering- och valideringsdata för modellsimuleringar. Resultaten från experimenten visade att den volymetriska flödesreduktionen minskade relativt sett med ökande markfukthalt, indikerande en övergång för svackdikets dominerande funktionalitet: vid låga initiala SWC var avrinningen tydligt dämpad (upp till 74%), medan för höga SWC innebar att transportfunktionen dominerade (med dämpningsgrad ner mot 17%). Avrinnande momentana toppflöden reducerades proportionellt mot volymreduktionen. Laggtiden för svackdikets utflödeshydrograf varierade mellan 5 och 15 minuter och reducerades med ökande markfukthalt. Fuktförhållandena i svackdiket påverkade avrinningsförloppet, flödesdämpning och efterföljande utsläpp, och enbart svackdikets översta markskikt berördes under de kortvariga bevattningscyklerna. I de tre testade svackdikena varierade jordart, initial markfukthalt, mättad hydraulisk konduktivitet och topografi signifikant. Mätningar med dubbelrings infiltrometrar gav följande resultat, 1.78, 4.04 samt 9.41 cm/h (n=9), vilket avvek från medelvärdesbaserat estimat från spatialt integrerade infiltrationshastigheter. Med avseende på spatial variabilitet påverkade endast svackdikenas topografi, i form av ojämnheter i och nära dikesbotten, avrinningsförloppen och bortledning under den inledande fasen av regnhändelsen. Sammantaget med uppskattningar av den lagrat vatten i marklagrets toppskikt, bedöms 4-32% av svackdikets ytavrinning från ett simulerade nederbördtillfälle med 2 månaders återkomststid kunna lagras tillfälligt. Mike SHE befanns kapabel att med god noggrannhet kunna reproducera naturbundna dräneringsförlopp och flöden i svackdiken, förutsatt tillbörlig kalibrering. God överensstämmelse (NSE>0.8) framkom inte bara mellan uppmätta och simulerade utgående hydrografer, utan också beträffande ändring av markfukthalt i ytligt marklager med snabb höjning av fukthalt upp emot full vattenmättnad. Däremot framkom endast mindre (eller total frånvaro av) överensstämmelse vad gäller markdjup av 0.2 m. Modellens output uppvisade låg känslighet för ursprunglig markfukthalt, speciellt gällande lågt flöde vilket resulterade i större residualer för simulerade toppflöden och avrinningsvolymer. För fältförsöken framkom att den initiala markfukthaltens spatiala variabilitet inte påverkade utflödet från svackdiket – i motsats till noggrannheten i dikets topografiska representation. Denna uppsats belyser samband och följdverkningar beträffande påverkan från undersökta parametrar på en modell för flödes- och vattenföring i ett svackdike och framledes framtida design av svackdiken.

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12

Ellenberger, Christine Spada. "Water Quality Impacts of Pure Chlorine Dioxide Pretreatment at the Roanoke County (Virginia) Water Treatment Plant". Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/30807.

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Chlorine dioxide (ClO₂) was included in the Spring Hollow Water Treatment Plant (Roanoke County, Virginia) to oxidize manganese and iron, prevent tastes and odors, and avoid the formation of excessive halogenated disinfection by-products. A state-of-the-art, gas:solid ClO₂ generation system manufactured by CDG Technology, Inc. was installed at the plant and is the first full-scale use of this technology in the world. The ClO₂ generator produces a feed stream free of chlorine, chlorite ion (ClO₂⁻), and chlorate ion (ClO₃⁻), resulting in lower by-product concentrations in the treatment system The objectives of this project were to study ClO₂ persistence and by-product concentrations throughout the treatment plant and distribution system and to evaluate granular activated carbon (GAC) columns for removing ClO₂⁻ from the finished water. The ClO₂ dosages applied during this study were relatively low (<0.75 mg/L), and, as a result, ClO₂⁻ concentrations never approached the maximum contaminant level (MCL) (1.0 mg/L). Likewise, the plant effluent ClO₂ concentration never approached the maximum residual disinfectant level (MRDL) (0.80 mg/L), but concentrations as high as 0.15 mg/L reformed in the distribution system by ClO₂⁻ reaction with chlorine. Chlorate ion was monitored despite the fact that no ClO₃⁻ MCL has been proposed, and concentrations were quite low (never greater than 0.10 mg/L) throughout the treatment plant and in the distribution system. The reasons for the low concentrations are that ClO₃⁻ is not produced by the gas-solid generator used at the facility and ClO₂⁻ concentrations in the clearwell prior to chlorination were uniformly low. The average ClO₂⁻ reduction upon passage of treated water through the GAC contactor was approximately 64 percent, but the GAC effectiveness was declining over the six-month study period. Apparently, GAC effectiveness, as shown by others, is short-lived, and if higher ClO₂ dosages are ever applied at the Roanoke County facility, the ClO₂⁻ concentrations will have to be reduced by either ferrous coagulants or reduced-sulfur compounds. Regenerated ClO₂ concentrations in the distribution system were below 0.2 mg/L, but concentrations as low as 0.03 mg/L were found at homes of customers who complained of odors. During this study, twelve complaints were received from eight customers, and each complainant had recently installed new carpeting, which has been shown to contribute volatile organics that react with ClO₂ to produce odors similar to kerosene and cat urine. While meeting the Cl₂ MCL likely will be no problem if the ClO₂ dose at the plant remains below 1.0 mg/L, the problem of offensive odors in the distribution system will likely continue as long as any ClO₂ is in the finished water when chlorine is present.
Master of Science

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13

Jacobson, Aaron. "Diffusion of Chemicals into Green Wood". Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/10516.

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Mass transport of chemicals into wood is important in kraft pulping. This thesis models small wood particles as cylinders and monitors how tritiated water and sulfide diffuse into the water-filled pores. Tritiated water diffusion is Fickian and diffuses completely into the water contained in the wood. Tortuosity values of the aspen and pine are tabulated. As particle size decreases, the tortuosity of the particles increases. As sulfide diffuses into wood, it is occluded from some water filled areas. Charge exclusion is a possible explanation for this. Sulfide and hydroxide transport into wood chips was displayed using indicators for each component. Pictures show sulfide ingress into the chip core faster, thus confirming the diffusion results. Fractionated sawdust was pulped to determine particle size effect on cooking and pulp properties.

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14

Lathuillière, Michael Jacques. "Land use effects on green water fluxes in Mato Grosso, Brazil". Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36950.

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The blue water - green water paradigm has been increasingly used to describe water resources. Blue water represents liquid flows in rivers or aquifers, while green water (GW) represents vapour exchanges with the atmosphere either as evaporation from soil or as transpiration from plants. This study assesses the impacts of land use change on GW fluxes in the Brazilian state of Mato Grosso, an ideal candidate for the study of GW in light of recent deforestation for pasture and soybean expansion, and the near complete reliance of its agricultural land base on precipitation as the GW source. Fluxes were estimated for 2000-2009 by combining the MODerate Resolution Imaging Spectroradiometer (MODIS) evapotranspiration product with forest cover change from Brazil’s National Institute of Space Research (INPE), as well as guidelines from the Food and Agriculture Organization (FAO) to model soybean, maize, sugar cane, cotton and pasture GW. In 2000, forest cover represented one third of the state’s land base and returned half of the state’s water vapour to the atmosphere. Annual total GW volumes decreased by 10 % between 2000 and 2009 at a rate of 16.2 km³y⁻¹ per year. Deforestation explained up to 27 % of variance in annual total volumes while agricultural expansion, as cropland and pasture, explained up to 20 %. Cropland GW doubled within the study time period, 75 % to 83 % of which constituted soybean GW. Pasture GW was 5 times larger than soybean GW and offset the increase in cropland GW. The greatest uncertainty lies in the role played by residual land use GW fluxes which were attributed to Brazilian savanna (cerrado), the Pantanal wetland, as well as unaccounted agricultural land left as fallow.

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15

Bolt, Matthew David. "Estimating green roofing and storm water regulation in an urban environment". Thesis, Boston University, 2012. https://hdl.handle.net/2144/12290.

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Thesis (M.A.)--Boston University
The City of Boston land use has altered the surrounding watersheds through creation of infrastructure, damming, landfill, and expansion of impervious surfaces. The continued growth of the City has historically outstripped the capacity of its combined storm and sanitary sewer system, necessitating discharges into area water bodies. In light of model forecasts by the Intergovernmental Panel on Climate Change predicting precipitation increases it is likely the already strained system will need additional capacity. Boston's tradition of expanding artificial capacity is compared to the City of Curitiba's enhanced natural capacity stormwater management plan. Limitations in both are discussed and the author concludes the City of Boston would benefit from increasing decentralized natural capacity through green rooftechnology. To investigate this claim remote sensing data was analyzed over three neighborhoods. The resulting available green roofing area was then combined with historical climate data to create a retention response model. The extrapolated city-wide model predicted retention of 19%-27% of total building received rainfall from 1983-2009. This model was then correlated with Combined Sewer Overflow (CSO) discharge National Pollutant Discharge Elimination System report data. The retention volume was found to accommodate most discharges in the FY2009 as well. Thus, extensive green roof technology presents a supplemental capacity building strategy for the City of Boston to avoid increases in future CSOs.

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16

Scholles, Carlos Eduardo Meneghetti. "Discursive and mediatic battles in Thomas King's Green Grass, Running Water". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/28206.

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O objetivo desta dissertação é o de investigar as disputas pelo poder subjacentes no texto literário do autor cherokee/canadense Thomas King, mais especificamente em seu romance publicado em 1993 intitulado Green Grass, Running Water. Serão destacadas as estratégias performáticas empregadas na desconstrução de representações opressivas de nativo-americanos por discursos ocidentais que compõem um complexo campo de batalha onde vozes em conflito disputam por direitos discursivos nas relações de poder. Se por um lado temos a tradição epistemológica positivista/cartesiana que trabalha há cinco séculos no sentido de exercer controle sobre as representações simbólicas dos nativo-americanos, a fim de que poder executivo e discursivo possa ser exercido sobre eles, por outro lado temos que Thomas King proporciona ao leitor o acesso a uma estrutura cíclica, não hierarquizada da narrativa e do epistêmio nativo-americanos. Esta investigação irá apontar os momentos de conflito entre essas vozes e analisará uma potencial interpretação democrática, de terceira via para esses encontros aparentemente binários. Espera-se ser possível indicar que Green Grass, Running Water propicia um privilegiado campo simbólico para que conflitos culturais e epistemológicos possam ocorrer e ser resolvidos com alguma espécie de resolução positiva em relação ao aspecto frequentemente belicoso dos engajamentos nativos e ocidentais. Para tanto, investigaremos a tradição bíblica e judaico-cristã de hierarquização e como o processo de nomeação de indivíduos e categorias permite que ocorra uma relação de dominação. Discutiremos a estrutura organizacional das comunidades, baseando-nos nas proposições de Zygmunt Bauman, com o intuito de averiguar de que forma o texto literário lida com questões como o pertencimento a grupos que possuem critérios subjetivos de aceitação, permitindo-nos responder se tais critérios permitem uma opção de filiação ou se representam uma demanda coletiva opressiva sobre o indivíduo. Uma análise dos discursos científicos de verdade também será feita, contrastando-os com a construção mítica coletiva das narrativas nativo-americanas como construções alternativas de verdade. Finalmente, teremos um capítulo sobre o poder narrativo da fotografia (mídia presente no romance em diversos momentos), no qual os usos da câmera serão descritos e analisados em seus potenciais de malícia e de narração distorcida.
The aim of this paper is to investigate the power struggles underlying the literary text of Canadian/Cherokee author Thomas King in the novel Green Grass, Running Water, published in 1993. We will highlight the performative strategies employed in the deconstruction of oppressive representations of the Native American by Western discursive and mediatic voices. The novel offers an interweaved narrative of Native and Western cultural materials that, together, will compose a complex battlefield of contentious voices that, ultimately, weigh on the balance of power relations to claim discursive rights. On the one hand, we have the epistemological tradition of a Positivist/Cartesian logic that has been working for five centuries to hold sway over the symbolic representations of the Native Americans in order to exert executive and discursive power over them; on the other hand, Thomas King provides the reader a glimpse of the cyclical, non-hierarchized structure of Native narrative and episteme. This investigation will point out the moments of conflict between these two voices and attempt to elaborate on the potential democratic/third-way interpretation of these seemingly binary encounters. We hope to be able to indicate that Green Grass, Running Water provides a privileged symbolic battleground for cultural and epistemological clashes to occur and be settled with some sort of positive resolution to the long-lasting contentious nature of Native and Western engagements. In order to accomplish that, we will delve into the biblical and Judeo-Christian tradition of hierachization and how the process of naming of individuals and categories allows for domination to occur. We will elaborate on the structural organization of communities, based on the propositions of Zygmunt Bauman, in order to assess how the literary text handles issues such as belonging to groups that have subjective criteria for acceptance, aiming at answering whether these criteria allow for an option of membership or if they pose as oppressive collective demands over the individual. An analysis of the scientific discourses of truth will also be provided, contrasting them with the collective mythmaking of Native American narratives as alternative constructors of truths. Finally, we will have a chapter on the narrative power of photography (a medium present in the novel at various moments), in which the uses of the camera are described and analyzed in their guileful and (mis)narrating potentials.

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17

Bedell, Willie B. "CAPITALIZATION OF GREEN SPACE AND WATER QUALITY INTO RESIDENTIAL HOUSING VALUES". UKnowledge, 2018. https://uknowledge.uky.edu/agecon_etds/63.

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This thesis investigates how proximity to parks, historic district designations, and water quality are valued at residential housing prices. The first essay argues that the negative influences of parks and historic districts, if not noticed, could promote negative externalities and unincentivized investments. I find a negative impact on housing values for a close proximity to a park, suggesting disamenities in park features. When the boundary discontinuity and park amenities are considered, I find a positive valuation for a park. Overall, these results imply a mixed influence of parks on homeowners. From the historic district standpoint, I find a positive valuation of the local historic districts over the surrounding neighborhoods. The latter findings indicate that the benefits of locally designated areas outweigh the negative impacts. The second essay researches a probable lead risk in the water supply on the residential market. I argue strongly for the possibility of hidden-type information relative to lead in water supplies. I find that the influence of lead risk in their water supply is not statistically significant. The test for asymmetric information validates the expectation that homes in the relatively high lead-risk neighborhoods might not be informed of the level of lead-risk in their water supply.

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18

De, Almeida Palmira Ndeshihala. "Green infrastructure: urban water management framework for Paarden Eiland, Cape Town". Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/18200.

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Includes bibliographical references
Cities in South Africa are currently experiencing rapid urbanisation, especially Cape Town. Infrastructure development has long been a critical component with a large amount of money invested in the development of hard infrastructure. However, in light of excessive stormwater runoff, the increased deterioration of surface water resources, degraded water quality, and the rapid progression of climate change around the global, many cities including Cape Town have progressed towards more sustainable forms of infrastructure development. Discourse surrounding sustainable development often encourages the improvement of the quality of urban areas without compromising the carrying capacity of ecosystems. This is a fairly new model in South Africa, which challenges the underlying principles of conventional infrastructural design and management. There is particularly an enthusiastic interest in the promotion of green infrastructure as a water sensitive design strategy in the management of stormwater and surface water. Presently, drainage systems for urban areas in Cape Town are constructed using principles of hard infrastructure, which often consist of complex man-made networks of underground tunnels and pipes that gather and direct stormwater runoff towards a surface waterbody. However, the extensive development of drainage infrastructure has led to increased stormwater runoff volumes, flooding, and flows. Urban stormwater runoff is known to be one of main sources of pollution and degradation of waterbodies, which has in turn resulted in the degradation of other environmental assets. Therefore, the planning, design, and implementation of infrastructural solutions there is a need to move towards a more sustainable and water sensitive model, in order to remediate these problems. Green infrastructure in this respect offers an opportunity to better manage both stormwater and surface water in a more holistic, cost-effective, efficient and ecological sound manner. The main objective of green infrastructure urban water management is to mimicking the natural hydrological cycle through various stormwater management interventions, in order to achieve what conventional drainage systems currently do and beyond their existing capacity. This dissertation uses Paarden Eiland as a case study and experimental project site in order to assess and investigate how green infrastructure can be utilised to effectively manage stormwater runoff and surface water within a heavily developed urban area. It explores the potential benefits this method of management provides in comparison to a conventional infrastructural approach of management. This study also highlights some of the critical issues and barriers that urban practitioners need to take into account when implementing such systems. A green infrastructure urban water management framework and conceptual layout are presented in order to demonstrate potential green infrastructure tools and strategies that may be used in retrofitting heavily developed areas, as well as provide guidance on how spatial planning can be utilised as a tool in the planning, design, and implementation of green infrastructure as well as in overcoming identified financial, technical, and institutional barriers.

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19

Broussard, Randal J. "An Analysis of the Green Knoll Salt Dome, located in the Southeast Green Canyon, Deep Water Gulf of Mexico". ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1858.

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The western portion of the Mississippi/Atwater fold belt in the Gulf of Mexico contains what is known as The Green Knoll Salt Dome. The creation and growth of this salt diapir is punctuated by salt deposition, salt migration, sediment loading, and is linked to the “Frampton” fold belt. An indicator of these growth periods is exhibited in an angular unconformity (halo-kinetic sequence boundary) that flanks the diapir. This unconformity developed during the Miocene-Pliocene chronostratigraphic boundary. The “Redwood” (Green Canyon 1001) prospect was drilled after the discovery of middle Miocene sands containing hydrocarbons in the Mad Dog field (GC 826). The objective Miocene sand in the “Redwood” borehole was thin due to this angular unconformity causing the sand to pinch out. An evaluation of seismic and well log data provided by Bureau of Ocean Energy Management indicated that the unconformity might not provide the seal needed to trap hydrocarbons on the flank of the salt dome, or it did not allow enough sand to be deposited. A palinspastic structural restoration of the Green Knoll Salt Dome revealed that the growth of the Green Knoll and Frampton are connected. It is still possible that if a well were to be drilled further down dip from where The “Redwood” prospect was drilled, one may find a potential hydrocarbon reservoir.

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20

Singh, Rohit. "Integrating the planning of green spaces and sustainable drainage systems". Thesis, Abertay University, 2012. https://rke.abertay.ac.uk/en/studentTheses/0a86d97d-4a27-429a-8dae-6afa03659ca9.

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In recent times urban flooding has become more frequent and more complex due to the effects of increasing urban areas and climate change. In some established urban areas the existing drainage infrastructure is unable to cope with the volume of surface runoff and flooding events are more frequent, therefore new approaches to create more space for water within developments are required. This research was conceived in that context. It aims to investigate the potential for integrating green space planning with water planning and to develop a framework for the same in order to reduce the risk of flooding. An extensive literature review was carried out in the areas of urban planning, water planning, planning legislations, and issues related to integrating green space and water planning. The review identified the need for an inclusive framework which could integrate aspects of green space and storm water planning more holistically to achieve greater spatial planning efficiency. To satisfy this need, a conceptual framework was developed which took into consideration the opinions of various stakeholders. The conceptual framework included green spaced planning for SUDS, recreational and storm water indicators and a mechanism for integrated evaluation of SUDS for recreation and storm water management. The conceptual framework provided a joint approach where both engineers and planners will need to work together for the development of integrated storm water and green space plans. The framework showed processes for both disciplines and also indicates how spatial planning and water planning interfaced so that there was clarity of roles. In order to evaluate integrated plans, an ‘integrated evaluation tool’ was developed which uses indicators from both the areas of green space planning and water planning. The evaluation tool also contained a scoring system which can be used to select storm water management options with more recreational potential. The tool provides a mechanism to balance the requirements of recreation and storm water management so that more holistic solutions can be developed by teams of engineers and planners. The conceptual framework and the integrated evaluation tool were applied to two case study catchments. Results from the case studies showed the relationship of spatial planning and flooding. It further tested whether recreational aspects could be integrated into storm water planning. A number of drainage options were tested to show the application of the evaluation tool under various scenarios. This results of the research showed that the conceptual framework was appropriate in both case study areas even though the areas had different patterns of development. It is therefore proposed that the approach has potential for wider application in other geographical areas. Results from the two areas also showed that the integrated approach established in this research could enhance the recreational aspects associated with urban storm water management. The framework presented in this thesis will potentially be of use to a wide range of stakeholders such policy makers, local authorities, water companies, consultants and researchers. It could also be useful in informing the evolution of planning policies and technical guidance associated with water and green space planning.

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21

Scott, Caroline Daphne. "The role of blue-green algae as marine fouling organisms". Thesis, University of Portsmouth, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282555.

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22

Alsup, Sarah Elizabeth. "EVALUATION OF METAL LEACHABILITY FROM GREEN ROOF SYSTEMS AND COMPONENTS". OpenSIUC, 2008. https://opensiuc.lib.siu.edu/theses/506.

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Green roof technology is becoming increasingly more popular in the U.S. as it provides several economical, sociological, and ecological benefits to urban environments. One specific advantage a vegetated rooftop is known to provide is its ability to retain water and release it at reduced rates. However, with increased interest in these systems, concerns regarding their influence on water quality have been raised. Green roofs can be complex systems and the degree to which water quality might be affected may be related to green roof construction and components within. To answer questions regarding green roof influence on metal contaminants in storm water runoff, a field study and a related laboratory study were designed to investigate potential impacts these systems may have on water quality with respect to heavy metals and some micronutrients. Overall, results obtained for Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn content observed in leachate collected from the constructs and media treatments from a green roof field study do not indicate that green roofs are a significant source of heavy metal and micronutrient contaminants in urban stormwater runoff and that planted Green Roof BlocksTM release less or the same metal content as planted built-in-place models. Elemental concentrations determined in effluent collected from treatments in the field study were collected for four rain events (June 28, 2007, October 18, 2007, February 4, 2008, and April 11, 2008) and compared to IEPA effluent standards to assess whether or not there were any negative impacts on water quality. Treatments for this portion of the investigation were empty built-in-place models (controls), planted and non-planted Arkalyte media at depths of 5 cm, 10 cm, 15 cm, and 20 cm in built-in place models, planted and non-planted commercial and potential green roof media in Green Roof BlocksTM. With the exception of excess Zn levels in collected effluent from the planted 10 cm treatments in October and the planted 5 cm treatments in February as well as the elevated Fe content in leachate obtained from planted glass media in October, metal concentration in effluent acquired from planted treatments were below effluent standards. Also determined to be above IEPA standards in October were Cu, Fe, and Pb measured in effluent obtained from non-planted glass media. The laboratory portion of this investigation evaluated several commercially-available substrates, bottom ash, lava rock, and composted pine bark to determine the total acid extractable and plant exchangeable content of eight elements (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn). In addition to this, effluent collected from planted and non-planted treatments using these substrates incorporated with 20% composted pine bark were examined over a course of three leaching events. While all elements examined were observed to be within levels normally found in soils, results from the total acid extractable experiments demonstrate large variation in metal concentration with each substrate and composted pine bark. With the exception of total extractable Cd, there were differences in concentrations for the remaining total acid extractable metals between the substrates and amendment tested. An artificial leaching study was conducted in the phytotron at Southern Illinois University Carbondale and consisted of eight repetitions of planted in addition to eight repetitions of non-planted pots containing known volumes of 20 % composted pine bark blended with Arkalyte, Haydite, Lassenite, Axis, bottom ash, Axis + bottom ash, and lava which were subsequently leached over three separate leaching events. Collected effluent was evaluated for Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn content as well as volume of water displaced as a function of planting treatment, number of times leached, and substrate type. Metal content in the leachates were typically an order of magnitude lower than values obtained from the batch studies, and the planting, substrate, and leaching interactions varied for each metal with Pb being the most complex. The volume of water displaced upon leachate collection increased across all substrates as a function of leaching event.

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23

Postillion, Frank G., Michael W. Block e August Merz. "Effects of the Green Valley Wastewater Treatment Facility Upon Groundwater Quality". Arizona-Nevada Academy of Science, 1986. http://hdl.handle.net/10150/296389.

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From the Proceedings of the 1986 Meetings of the Arizona Section - American Water Resources Association, Hydrology Section - Arizona-Nevada Academy of Science and the Arizona Hydrological Society - April 19, 1986, Glendale Community College, Glendale, Arizona
The Green Valley Wastewater Treatment Facility (GVWWTF) is about 20 miles south of Tucson, Arizona. Locally, the aquifer consists of interbedded sands, silts and gravels. Depth to water near the facility is about 160 feet with transmissivity ranging from 32,000 to 48,000 gpd /ft. Ground water quality has historically been poor near the facility due to deep percolation of irrigation return flow. With the retirement of farm land, however, ground water quality has improved considerably. The only problem with well water downgradient of GVWWTF has been with total coliform where several samples exceeded public drinking water standards. Current inflow of about 1.1 mgd will increase to 4.5 mgd by 2005. Flow net and mass balance analyses indicate effluent recharge by percolation beds will increase from 1060 AF /year to 4130 AF /year during this period. A mass balance model predicts TDS will increase from about 585 to 615 mg/l, nitrate-N will increase from 9.2 to 9.9 mg/l, chloride will increase from 50 to 75 mg/1, and sulfate will decrease by 25 mg/l to 115 mg/l. Further study of pond disinfection for prevention of microbiological contamination is suggested. Additionally, effluent reuse and an enhanced monitoring program including upgradient and downgradient wells are encouraged.

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24

Yukruk, Funda. "Water Soluble Green Perylenediimide (pdi) Dyes As Potential Sensitizers For Photodynamic Therapy". Phd thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/3/12605693/index.pdf.

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Photodynamic therapy has been established as one of the approaches for the treatment of various malignant tumors. While most of the reagents used for this purpose are porphyrin derivatives, there is a strong motivation for finding novel and better sensitizers. Perylenediimides are known for their photo- and chemical stability, but they do not have absorptions in the red end of the visible spectrum. However, recently reported green perylenediimides which have dialkylamino substituents on the perylene core, provide an alternative. To that end, we have designed and synthesized novel green perylenediimides with remarkable water solubility at neutral pH and absorption peaks beyond 650 nm. We demonstrated that on red-light excitation, singlet oxygen trap 1,3-diphenyl-iso-benzofuran is rapidly degraded. We also carried out cell culture experiments
an important parameter to be optimized for practical application as a novel photodynamic therapy agent was the excited dye toxicity to dark toxicity. Our results confirmed that these novel perylenediimides acted as sensitizers generating singlet oxygen and the initial in vitro biological experiments demonstrated their potential utility in photodynamic therapy.

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25

Allen, Andrew J. (Andrew John) 1978. "Green chemistry : dense carbon dioxide and water as environmentally benign reaction media". Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28656.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2004.
Includes bibliographical references.
(cont.) was investigated in scCO₂, and the cycloaddition between cyclopentadiene and methyl vinyl ketone (MVK) was studied in an scCO₂/liquid water environment. Nitrogen chemistry, specifically the synthesis of nitrogen heterocycles from amines, was also studied in scCO₂ and scCO₂/liquid water systems. The objective of studying the Diels-Alder cycloaddition of 9-hydroxymethylanthracene with N-ethylmaleimide in scCO₂ was to demonstrate the ability of scCO₂ to dramatically accelerate the rate of this reaction when compared to conventional solvents. Using spectroscopy to track the disappearance of the 9-hydroxymethylanthracene peak, it was found that this reaction proceeds at rates in scCO₂ that are significantly faster than in traditional organic solvents. It was also observed that the reaction rate constant increased with decreasing density, opposite the trend normally observed for most reactions conducted in scCO₂. On the basis of the low solubility of 9-hydroxymethylanthracene in scCO₂ and similar results observed in fluorocarbon solvents (fluorocarbons and scCO₂ are known to behave similarly as solvents), a solvophobic mechanism was inferred as the cause of the rate acceleration observed for this particular reaction in scCO₂. In order to utilize the complementary solvation powers of scCO₂ and water, a second Diels-Alder reaction, cyclopentadiene with MVK, was studied in an scCO₂/liquid water mixture. Specifically, the effect of MVK concentration on the selectivity and conversion was studied under both silent and sonicated conditions ...
With an ever increasing focus on reducing the environmental impact of solvent releases on human health and the environment, the replacement of conventional, organic solvents with alternative compounds that are inherently benign has attracted much attention in both industry and academia. Supercritical carbon dioxide (scCO₂) and water are two alternative compounds that are of particular interest because they are non-toxic, non-flammable, readily available, and cheap. Although scCO₂ has been successfully used in industry as a solvent for selective extraction (e.g. extraction of caffeine from coffee beans), development of scCO₂ as a reaction solvent has been less successful due to its limited solvation power for many organic reagents of interest. In addition scCO₂ has generally been shown to reduce both the reaction rate and selectivity of many reactions when compared to conventional solvents. Unlike scCO₂, water is known to significantly accelerate reaction rates and improve selectivities over that obtainable in conventional solvents. However, most organic compounds are insoluble in water which has limited its use as a reaction solvent for industrial-scale processes. In order to replace conventional solvents with scCO₂ and/or water, significant technological advantages resulting from the use of these compounds will have to be demonstrated. This research attempts to demonstrate some potential advantages of using scCO₂ and scCO₂/water as reaction media for several synthetic transformations of interest. The Diels-Alder cycloaddition of 9-hydroxymethylanthracene and N-ethylmaleimide
by Andrew J. Allen.
S.M.

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26

Sande, Leif Andrew. "Experimental Studies on Infiltration/Soil-Water Movement Processes and Green-AMPT Modeling". Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/29329.

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Experimental studies on infiltration/soil-water movement processes are vital to better understanding movement of soil-water in the vadose zone. The objective of this experimental research was to investigate infiltration/soil-water movement processes utilizing laboratory experiments and computer modeling. Small scale laboratory soil box infiltration experiments were conducted and utilized for the improved parameterization of the Green-Ampt (GA) saturated moisture content parameter to produce an effective moisture content parameter (Be) for utilization in a modified GA model. By incorporating ?e values into GA modeling, modeling results showed greatly improved wetting front prediction across different soil conditions. A new soil packing method was proposed for replicating complex microtopographical surfaces with uniform bulk densities in laboratory soil box experiments which proved efficient and effective at accomplishing both objectives. A rainfall simulator and an instantaneous-profile laser scanner were used to simulate rainfall and quantify surface microtopography for experiments. The results clearly show the effect of microtopography on infiltration and soil-water movement characteristics. This offers valuable insight into infiltration/soil-water movement processes as affected by different soil and surface microtopographic conditions.
National Science Foundation (Grant No. EAR-0907588)

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27

Chambers, Benjamin Daniel. "Understanding the Selection and Use of Water Related Innovations in Green Buildings". Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/25298.

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This manuscript provides an understanding of water conservation related innovations in green buildings, both in terms of what is being selected in design phase and how professionals perceive their experiences with these innovations. The innovations examined include toilets, showers, sinks, plumbing, water heating, appliances, alternative water sources, landscaping, performance monitoring, and user education. It contains a literature review of unanticipated consequences associated with these innovations, and creates a framework for categorizing these based on a synthesis of the literature of unanticipated consequences. A review of certification documents from the Leadership in Energy and Environmental Design (LEED) rating system identifies what landscaping, toilet, and shower innovations are most commonly designed for in LEED certified buildings. These data are also used to identify differences in innovation selection across climate regimes. An internet survey of green building professionals provides a picture of satisfaction with these innovations in practice. It also gives examples of these experiences so that future users can take advantage or take caution as necessary.
Master of Science

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28

Qiao, Qiquan. "Green Organic Solar Cells from a Water Soluble Polymer and Nancrystalline TiO2". VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/1078.

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The cost of the present generation of inorganic silicon solar cells is very high and further breakthroughs in cost and efficiency using traditional materials are becoming less and less likely after over 50 years of development. Next generation organic solar cells offer a solution to the limitations of silicon through the vision of low-cost, liquid-based, large area fabrication technology based on polymer and nanomaterials at room temperature. However, most polymers used in solar cells are dissolved in organic solvents such as xylene, toluene, chloroform, and chlorobenzene. Such solvents are harmful to people and environments, leading to higher costs due to complicated waste disposal processing. This is in conflict with the low cost, green, and renewable energy for which we are aiming. To realize a green organic solar cell, a novel solar cell has been created using an environmentally friendly water-soluble thiophene polymer [(Sodium poly[2-(3-thienyl)-ethoxy-4-butylsulfonate])] (PTEBS) and nanocrystalline TiO2. This novel system has shown great potential in photovoltaics the work has garnered the attention of the international community.In our innovative solar cells, the water-soluble polythiophene (PTEBS) is used as electron donor. Nanoparticle TiO2 acts as electron acceptor. PTEBS/TiO2 solar cells with various structures including bilayer heterojunctions, bulk heterojunctions and a hybrid of bilayer and bulk heterojunctions have been developed and explored. These results are comparable to the best polymer/metal-oxide solar cells reported by other groups using organic solvents.In summary, this is the first time that green solar cells have been fabricated from environmentally friendly water-soluble polymers. By using water as the solvent and utilizing liquid-based processing, the cost of the energy generated by this type of solar cell will be further lowered. In addition, the flexible polymer offers the ease of fabrication and integration into different devices.

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29

Rivera, Brian. "Analysis of the Florida's Showcase Green Envirohome Water/Wastewater Systems and Development of a Cost-Benefit Green Roof Optimization Model". Master's thesis, University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2580.

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The Florida Showcase Green Envirohome (FSGE) incorporates many green technologies. FSGE is built to meet or exceed 12 green building guidelines and obtain 8 green building certificates. The two-story 3292 ft2 home is a "Near Zero-Loss Home", "Near Zero-Energy Home", "Near Zero-Runoff Home", and "Near Zero-Maintenance Home". It is spawned from the consumer-driven necessity to build a home resistant to hurricanes, tornadoes, floods, fire, mold, termites, impacts, and even earthquakes given up to 500% increase in insurance premiums in natural disaster zones, the dwindling flexibility and coverage of insurance policies, and rising energy, water and maintenance costs (FSGE 2008). The FSGE captures its stormwater runoff from the green roof, metal roof and wood decking area and routes it to the sustainable water cistern. Graywater from the home (after being disinfected using ozone) is also routed to the sustainable water cistern. This water stored in the sustainable water cistern is used for irrigation of the green roof, ground level landscape, and for toilet flushing water. This study was done in two phases. During phase one, only stormwater runoff from the green roof, metal roof and wood decking area is routed to the sustainable water cistern. Then, during phase two, the water from the graywater system is added to the sustainable water cistern. The sustainable water cistern quality is analyzed during both phases to determine if the water is acceptable for irrigation and also if it is suitable for use as toilet flushing water. The water quality of the sustainable cistern is acceptable for irrigation. The intent of the home is to not pollute the environment, so as much nutrients as possible should be removed from the wastewater before it is discharged into the groundwater. Thus, the FSGE design is to evaluate a new on-site sewage treatment and disposal (OSTD) system which consists of a sorption media labeled as Bold and GoldTM filtration media. The Bold and GoldTM filtration media is a mixture of tire crumb and other materials. This new OSTD system has sampling ports through the system to monitor the wastewater quality as it passes through. Also, the effluent wastewater quality is compared to that of a conventional system on the campus of the University of Central Florida. The cost-benefit optimization model focused on designing a residential home which incorporated a green roof, cistern and graywater systems. This model had two forms, the base model and the grey linear model. The base model used current average cost of construction of materials and installation. The grey model used an interval for the cost of construction materials and green roof energy savings. Both models included a probabilistic term to describe the rainfall amount. The cost and energy operation of a typical Florida home was used as a case study for these models. Also, some of the parameters of the model were varied to determine their effect on the results. The modeling showed that the FSGE 4500 gallon cistern design was cost effective in providing irrigation water. Also, the green roof area could have been smaller to be cost effective, because the green roof cost is relatively much higher than the cost of a regular roof.
M.S.Env.E.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Environmental Engr MSEnvE

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30

Pricope, Narcisa. "Modeling Soil Erosion in the Upper Green River, KY". TopSCHOLAR®, 2006. http://digitalcommons.wku.edu/theses/258.

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Off-site soil erosion has tremendous impacts on the present state of most river systems throughout the United States, contributing sediments to channels mainly as nonpoint pollution resulting from land-use and agricultural practices and leading to sedimentation downstream and downwind, a decrease in the transport capacity of streams, increase in the risk of flooding, filling reservoirs, and eutrophication. A primary focus in examining the problems associated with soil erosion arid ultimately in proposing control measures should be on identifying the sources of the sediment. Therefore, a model that would be able to assess soil erosion needs to start by identifying the sediment sources and delivery paths to channels, link these sediment supply processes to in-channel sediment transport and storage and ultimately to basin sediment yield. This study focuses on the Upper Green River Basin in Kentucky and is concerned with analyzing hillslope erosion rates using The Unit Stream Power Erosion and Deposition soil erosion model (Mitas and Mitasova, 1996) and GIS, and thereby estimating patterns of sediment supply to rivers in order to predict which portions of the channel network are more likely to store large amounts of fine sediments. Results indicate that much of the eroded sediments are redistributed within the hillslope system, but also that a large proportion is delivered to the channel. These predictions have been tested by sampling the fine sediment content of the streambed at key locations along the channel network and comparing the observed patterns to those predicted by the soil erosion model. By linking topographic and soil characteristics with land cover data, it has been concluded that high intensity erosion tends to occur at contact between different vegetation covers, on barren lands and croplands, and 15-25% slopes poorly protected by vegetation. Erosion ""hot spots"" have been identified in the Pitman Creek HUC 05110001-90-130 and 05110001-90-050, both part of the Big Pitman Creek sub-basin, as well as in Mill and Falling Timber Creeks with lower intensity.

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31

Busch, Sarah Elizabeth. "Impact of Flow Rate and Water Age on Opportunistic Pathogen Growth: Implications for Water Conservation, Fixture Design, and Policy". Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/104182.

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Water conservation efforts have led to a decrease of flow rates in buildings, increasing water retention time (WRT) and sometimes opportunistic pathogens (OPs) growth. A novel experiment with replicated distal pipes operated at commonly used flow rates was designed to evaluate the effects of water age, flush frequency, flow rate, pipe diameter, water temperature, disinfectant residual presence, and microbial regrowth in hot and cold pipes. In cold water, total bacterial regrowth was a function of water age, plateauing after approximately 6 days at cell counts 20 times higher than influent water with minimal disinfectants. In warm (40 °C) water, most regrowth occurred in the heater tank, reducing the relative growth in the pipes. When cold water with ~1 mg/L chloramine was present, cold-water total bacteria regrowth plateaued after about 2 days WRT with cell counts 14 times higher than influent water, but regrowth still occurred in the heater tank. With 1 mg/L chloramine and elevated heater temperature (60 °C), regrowth in the tank was suppressed and cell counts in the pipes increased 82 times above cold-water influent levels at 7.5 days WRT. Legionella spp. and Mycobacterium spp. demonstrated opposite responses to flow rate with chloramine minimization. The highest levels of Legionella spp. (1.7 log higher than influent) were present when flow velocity was >2 feet per second (fps), but the highest levels of Mycobacterium spp. (1.5 log higher than influent) were observed at the lowest flow velocity (0.33 fps). This study highlights the tradeoffs between water conservation and water quality.
Master of Science
Regulations that decrease flow rates of faucets and showers have driven water conservation in buildings, increasing the time water sits in pipes and tanks (i.e., water retention time or WRT) elevating the likelihood of harmful bacterial growth. A novel faucet rig was designed to carry out a comprehensive experiment revealing the combined effects of WRT, flush frequency, flow rate, pipe diameter, water temperature, and disinfectant residual presence on water quality at the tap. In water without disinfectant, growth in cold water pipes increased with WRT, but in hot water the growth of bacteria occurred mostly in the warm water tank at 40 °C, which is a temperature known to leave a system vulnerable to bacterial growth. Cold pipes with a disinfectant residual saw a decrease in bacterial regrowth in comparison to cold pipes without disinfectant. However, if there was a disinfectant residual and an elevated water heater temperature set point in the tank, regrowth occurred when water was in the pipes at room temperature and there were lower disinfectant residuals. Potentially harmful bacteria, like Legionella spp. and Mycobacterium spp., which cause Legionnaires' disease and nontuberculous Mycobacteria (NTM) infections, grew more readily at higher flow rates, whereas others grew less readily, but all harmful bacteria were reduced by lowering WRT to less than ≈ 2 days and maintaining the water at 60 °C with a disinfectant. This study has important implications for regulations requiring minimum disinfectant levels to buildings, faucet flow rates regulations, and design and operation of building plumbing systems.

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32

Coyle, Sadie Marie. "Investigations of microcystins (cyanobacterial peptide toxins) : detection, purification and analysis". Thesis, Robert Gordon University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360091.

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33

Allread, Tyler M. "Channel Narrowing of the Green River near Green River, Utah: History, Rates, and Processes of Narrowing". DigitalCommons@USU, 1997. https://digitalcommons.usu.edu/etd/6525.

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Abstract (sommario):

Previous scientific research has documented channel narrowing on the Green River near Green River, Utah, but the exact timing, rates, and causal mechanisms of that narrowing have been the source of disagreement in the scientific literature. This thesis demonstrates that the Green River has narrowed in two separate periods during the last 100 years. The narrowing is driven primarily by changes in the hydrologic regime and not by the invasion of saltcedar. The channel narrowed between 1930 and 1938, when a shift from wetter than normal conditions to a period of draught led to a reduction in river discharge. Channel width then remained relatively stable until construction of Flaming Gorge Dam in 1962, despite the presence of saltcedar. Narrowing has occurred since dam construction. Detailed analysis of the formation of an inset floodplain deposit indicates that it formed by a process of vertical accretion, during incremental events. Inset bank deposits within the study area are composed primarily of particles smaller than 0.125 mm. Measurement of suspended sand distribution within the water column shows that particles of this size are carried in suspension by the 2-yr flood. Continued vertical accretion over time elevated the floodplain surface until inundation rarely occurs.

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34

Bürgow, Grit [Verfasser]. "Urban Aquaculture : Water-sensitive transformation of cityscapes via blue-green infrastructures / Grit Bürgow". Aachen : Shaker, 2014. http://d-nb.info/1066197199/34.

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35

Dabbaghian, Mohammadreza. "Water quality and lifecycle assessment of green roof systems in semi-arid climate". Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46609.

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Abstract (sommario):

Non-point source pollution contributes significantly to stormwater contamination in urban areas. Low impact development (LID) techniques and technologies are developed as a response to these challenges. Green buildings incorporate environmentally responsible and resource-efficient technologies to reduce environmental impacts over their life cycle. Green roof systems are broadly recognized as LID practices that may improve urban environmental quality by reducing stormwater runoffs. Potential impact of green roofs on the quality of runoff may be a deterrent to wider application of green roof systems. Organic and inorganic fertilizers in growing media, for example, may contaminate runoff and generate non-point source pollution. Recently, various environmental assessment methods have been developed to assess the environmental performance of green building technologies. Methods developed to date, however, are insufficient for accurate quantitative estimation and evaluation of triple-bottom-line (TBL) sustainability performance objectives (i.e. economic, environmental, and social) in the context of green building technologies. This study has two main objectives. First, it aims to investigate the performance of green roofs in the context of runoff water quality in the semi-arid environment of Kelowna, British Columbia, Canada. An experimental investigation has been conducted to enhance green roof performance by addition of a supplemental filtration layer. Runoff and precipitation samples were analyzed for water quality parameters including pH, nitrate and ammonia. In the next step, a quantitative sustainability evaluation framework for green building technologies was developed. The proposed framework integrates fuzzy-analytical hierarchy process (FAHP) integrated with a ‘cradle-to-grave’ life cycle assessment to address interactions and influence of various TBL criteria. The experiment results showed that the generic green roofs runoff is acceptable for domestic reclaimed water used under Cnadaian guidelines for domestic reclaimed water. The analysis shows that green roofs are able to reduce non-point source nitrate and ammonia concentrations. The installation of extensive green roofs could decrease a large amount of non-point source nitrate and ammonia emissions in an urban area during their lifespan. The utility of the FAHP approach is demonstrated by comparing sustainability performance of two generic green roof systems with a conventional roof. The results show that an ‘extensive’ green roof system is a more desirable option in terms of long-term sustainability performance criteria.

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36

Broekhuizen, Ico. "Uncertainties in rainfall-runoff modelling of green urban drainage systems : Measurements, data selection and model structure". Licentiate thesis, Luleå tekniska universitet, Arkitektur och vatten, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-73367.

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Abstract (sommario):

Green urban drainage systems are used to avoid flooding and damages to people and property, while limiting the downstream flooding and water quality problems caused by pipe-based drainage systems. Computer models are used to analyse and predict the performance of such systems for design and operation purposes. Such models are simplifications of reality and based on uncertain measured data, so uncertainties will be involved in the modelling process and its outcomes, which can affect the design and operation of these systems. These uncertainties have been investigated extensively for traditional pipe-based urban drainage systems, but not yet for green alternatives. Therefore, the overall objective of this thesis is to contribute to improved applicability and reliability of computer models of green urban drainage systems. Specifically, the thesis aims to (1) improve understanding of the uncertainties arising from (a) model structure and (b) calibration data selection, (2) evaluate two alternative calibration methods for green urban drainage models, (3) discuss desirable structural features in urban drainage models, and (4) evaluate several sensors for hydrometeorological measurements in urban catchments. The effects of model structure uncertainty were investigated using long-term simulations of synthetic catchments with varying soil types and depths for three different models. First, it was found that surface runoff could be a significant part of the annual water balance in all three models, depending on the soil type and depth considered. Second, differences were found in how sensitive the different models were to changes in soil type and depth. Third, the variation between different models was often large compared to the variation between different soil types. Fourth, the magnitude of inter-annual and inter-event variation varied between the models. Overall, the findings indicate that significant differences may occur in urban drainage modelling studies, depending on which model is used, and this may affect the design or operation of such systems. The uncertainty from calibration data selection was investigated primarily by calibrating both a low- and high-resolution stormwater model using different sets of events. These event sets used different rainfall-runoff statistics to rank all observed events before selecting the top six for use in calibration. In addition, they varied by either calibrating all parameters simultaneously, or by calibrating parameters for impervious and pervious surfaces separately. This last approach sped up the calibration process. In the validation period the high-resolution models performed better than their low-resolution counterparts and the two-stage calibrations matched runoff volume and peak flows better than single-stage calibrations. Overall, the way in which the calibration events are selected was shown to have a major impact on the performance of the calibrated model. Calibration data selection was also investigated by examining different ways of including soil water content (SWC) observations in the calibration process of a model of a swale. Some model parameters could be identified from SWC, but not from outflow observations. Including SWC in the model evaluation affected the precision of swale outflow predictions. Different ways of setting initial conditions in the model (observations or an equilibrium condition) affected both of these findings. The precipitation sensors used in this thesis showed generally satisfactory performance in field calibration checks. Different types of precipitation sensors were associated with different requirements for maintenance and data acquisition. Sensors for sewer pipe flow rates showed good agreement with a reference instrument in the laboratory, as long as installation conditions were good. Higher pipe slopes and upstream obstacles lead to larger measurement errors, but this last effect was reduced by increasing water levels in the pipe. Sensor fouling was a source of errors and gaps in field measurements, showing that regular maintenance is required. The findings show that the evaluated flow sensors can perform satisfactorily, if measurement sites are carefully selected.
Reliable modeling of green infrastructure in green urban catchments
Assessment and modeling of green infrastructure for urban catchments

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Manamathela, Sibongile Amelia. "The water footprint of selected crops within the Olifants/Doorn Catchment, South Africa". University of the Western Cape, 2014. http://hdl.handle.net/11394/4751.

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>Magister Scientiae - MSc
Rapidly increasing global population is adding more pressure to the agricultural sector to produce more food to meet growing demands. However the sector is already faced with a challenge to reduce freshwater utilisation as this sector is currently using approximately 70% of global water freshwater resources. In South Africa, the agriculture sector utilizes approximately 62% of freshwater resources and contributes directly about5% to the Gross Domestic Product. South Africa is a water scarce country receiving less than 500mm/year of precipitation in most parts of the country, and consequently approximately 90% of the crops are grown under irrigation. Studies have evaluated irrigation practices and crop water use in the country. However information is lacking on the full impact of South African horticultural products on freshwater resources. The water footprint concept can be used to indicate the total and source (blue/green) of water used to produce the crops. Information about water footprint (WF) can be used for identifying opportunities to reduce the water consumption associated with production of vegetables and fruits at the field to farm- gate levels, including the more effective use of rainfall (green water) as opposed to water abstracted from rivers and groundwater (Blue water). It can also be used to understand water related risks associated with the production of crops and facilitate water allocation and management at catchment/water management scale. While the potential value of water footprint information is well recognized there is still inadequate knowledge on how best to determine the water footprints of various crops within a local context. The aim of this study was to determine the water footprint and the crop water productivity of navel oranges, pink lady apples and potatoes produced with the Olifant/Doorn water management area in South Africa.The water footprint of the navel oranges, pink lady apples and potatoes assessed following the water footprint network method was 125 litres/ kg, 108 litres/kg and 65 litres/ kg respectively. The study concluded that water footprint studies should be carried out on the whole catchment instead of one farm in order to assess the sustainability of the process.

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Post, Donald F., Jamie P. Dubay e Allan D. Matthias. "The Effects of Rock and Green Waste Mulches on Soil Moisture and Soil Temperature". Arizona-Nevada Academy of Science, 2000. http://hdl.handle.net/10150/296563.

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39

Rönneke, Johanna. "Water as a common resource - Whose responsibility? : A Study on the Efficiency of Community Involvement in Water Management in India". Thesis, University of Kalmar, University of Kalmar, School of Pure and Applied Natural Sciences, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hik:diva-2076.

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Abstract (sommario):

The aim of this study was to evaluate the impact of community involvement on management of water tanks in the Arkavathi sub-basin in the state of Karnataka, South India. Water management was analysed from a socio-environmental perspective, with emphasis on village-level stakeholders’ roles and perceived responsibility. The efficiency of community participation was investigated by comparing two villages having undergone the same World Bank launched program to restore water bodies traditionally used to sustain the livelihood of the rural population. In one village there was a resistance towards how the implementation of the tank rejuvenation project had been performed, in the other there was no local involvement.

A minor field study was conducted by visiting the two villages. Qualitative interviews were held with village-level stakeholders of three age groups, to analyse changes over time in knowledge and attitudes. Additionally, ocular observation and photo documentation were made of the study areas. Some informal interviews were carried out with members of an external non-governmental organisation and locals in the study villages. The collected data were analysed by comparing the results for the two villages, as well as the results of the different age groups and genders.

There were significant differences in awareness and sense of responsibility, but not knowledge, between the two villages. In the village with a community involvement resisting the governmental scheme for tank renovation, this involvement had proved to be of some advantage to the local community. Contrary to the guidelines, the governmental implementation of the water management strategy did not include local stakeholders’ participation, nor were the tanks restored. Overall, the villagers considered the tank management to be the responsibility of external authorities. There were generally no significant differences between the age groups or men and women, though there were indications of a lower level of knowledge and awareness in women. Absence of effective institutions for water management on all levels as well as difficulties in mainatining efficient village level leadership for community participation are factors causing a major gap between planning and implementation.

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Van, Der Walt Johannes Tinus. "Development of a sustainability index for South African dwellings incorporating green roofs, rainwater harvesting and greywater re-use". Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20138.

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Abstract (sommario):

Thesis (MScEng)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: South African water service providers experience major problems with providing adequate water services to consumers. Water service providers in South African urban areas rely on traditional centralised infrastructure, such as bulk supply networks, to provide water services. Alternative supply and stormwater drainage methods should be encouraged to help mitigate these problems. The researcher thus aims to quantify the potential impact that three alternative methods may have on a given dwelling in terms of its dependence on traditional bulk water services. The three alternatives considered in this thesis are the construction of green roofs, rainwater harvesting and greywater re-use. An efficiency of dwelling water use index (EDWI) was developed during this research project. It was designed in such a way as to show what portion of municipal water services could be replaced within the given dwelling by using the proposed techniques. The final EDWI-rating is obtained by using the EDWI-software tool developed as a part of this research. The derived EDWI-rating ranges from 0 to 100, with a rating of 100 indicating a dwelling requiring only the removal of a portion of sewage by a municipality, but no external water supply. Such a dwelling would also not require any water from a municipal network to meet domestic demand and all stormwater from its roof would be utilised within the plot boundaries. Results presented in this thesis illustrate how different geographical regions require different system specifications to obtain optimal EDWI-ratings, thereby lowering their dependence on the respective municipal water services. Validation of the EDWI-system proved difficult as no similar index could be found during the literature review. It was therefore decided to benchmark the EDWI-system using three model dwellings with nine configurations producing a total of 27 analyses. The EDWI-system provides a conceptual foundation for sustainable water services to South African households in serviced urban areas. Future work could further improve the EDWI-system by testing its practical application so that it may be extended to act as a national barometer, used to compare decentralised water services in terms of sustainability.
AFRIKAANSE OPSOMMING:Suid-Afrikaanse waterdiensverskaffers ondervind groot probleme met die voorsiening van voldoende waterdienste aan verbruikers. Waterdiensverskaffers in Suid-Afrikaanse stedelike gebiede maak staat op tradisionele gesentraliseerde infrastruktuur, soos grootmaatvoorsienings netwerke, om waterdienste te verskaf. Alternatiewe voorsienings- en stormwater dreineringsmetodes moet aangemoedig word om hierdie probleme aan te spreek. Die studie poog dus om die potensiële impak wat drie alternatiewe moontlikhede kan hê op 'n gegewe woning in terme van sy afhanklikheid van die tradisionele waterdienste te kwantifiseer. Die drie alternatiewe moontlikhede wat in hierdie studie ingesluit word is die konstruksie van groendakke, reënwater oes en grys water hergebruik. 'n Huishoudelike water gebruik doeltreffendheids indeks (EDWI) is ontwikkel gedurende hierdie navorsingsprojek. Die indeks is ontwerp om aan te dui watter gedeelte van munisipale waterdienste deur die voorgestelde tegnieke vervang kan word. Die finale EDWI-gradering is verkry deur gebruik te maak van die EDWI-programmatuur wat ontwikkel is gedurende die navorsing. Die afgeleide EDWI- gradering wissel tussen 0 en 100, met 'n telling van 100 wat ‘n woning voorstel wat slegs die verwydering van 'n gedeelte van die riool deur die munisipaliteit vereis, maar wat geen eksterne watervoorsiening benodig nie. So 'n woning vereis dus geen water van ‗n munisipale netwerk nie, en alle stormwater van die dak word binne die erf gebruik. Resultate wat in hierdie studie voorgelê word illustreer hoe verskillende geografiese streke ander stelsel spesifikasies vereis om optimale EDWI-gradering te verkry. Die navorser kon geen indeks kry wat soortgelyk is aan die EDWI-stelsel om dit mee te vergelyk nie. Dit was gevolglik besluit om die indeks te standardiseer deur gebruik te maak van drie model huise met nege samestellings van alternatiewe, waardeur 27 ontledings ontwikkel was. Die EDWI-stelsel bied 'n konseptuele grondslag vir volhoubare waterdienste vir Suid-Afrikaanse huishoudings in gedienste stedelike gebiede. Toekomstige navorsing kan die EDWI-stelsel verder verbeter deur die praktiese toepassing te toets. Die stelsel kan uitgebrei word om ‗n nationale barometer vorm wat gebruik kan word om desentralisasie van waterdienste te meet in konteks van volhoubaarheid.

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Mancipe, Muñoz Nestor Alonso. "Detention-based Green/Gray Infrastructure Framework to Control Combined Sewer Overflows". University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439307033.

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42

Brook, J. G. "Relationships between Cladophora glomerata and aquatic macrophytes". Thesis, University of Liverpool, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377118.

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43

Rossi, Gianmarco. "modeling of proton exchange membrane water electrolyzer for green hydrogen production from solar energy". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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Abstract (sommario):

Hydrogen is considered one of the means by which to store energy coming from renewable and intermittent power sources. With the growing capacity of renewable energy sources, a storage system is required to not waste energy. PEM electrolysis provides a sustainable solution for the production of hydrogen and is well suited to couple with energy sources such as solar and wind. This work reports the development of simulation software to estimate the performance of a proton exchange membrane electrolyzer working at atmospheric or low pressure conditions connected to a solar energy source. The electrolyzer is defined from a validated reference semi-empirical model, which allows for simulating the electrochemical, thermal and H2 output flow behaviours with enough precision for engineering applications. An algorithm for a fitting procedure to characterize commercial products, and functions for power modulation have been implemented. A series of simulations have been carried on, starting from real photovoltaic data of input power, and the output values have been discussed, with particular attention to output flow rate, thermal behaviour and the cooling demand in order to preserve the operation of the electrolyzer.

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Boening, Kathryn Margaret. "Impacts of Green Infrastructure Practices and Rainfall Characteristics on Sewershed Hydrology and Water Quality". The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595352797878418.

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45

Lenton, Timothy Michael. "Redfields green ocean : a geophysical model of marine nitrate, phosphate and atmospheric oxygen regulation". Thesis, University of East Anglia, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389395.

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46

Sjöholm, Pia. "Water strategies for Swedish sustainable urban planning : A comparison between certification systems and urban water research". Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-213400.

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Abstract (sommario):

Sustainable development is gaining more focus than ever, and sustainable urban water management is increasingly being incorporated in urban planning worldwide. Internationally, certification systems for sustainable urban planning have gained popularity, and a Swedish version of the British certification system BREEAM Communities is on its way. In this degree project the technical water related aspects of the certification system BREEAMCommunities are analyzed and compared with the corresponding aspects of the American certification system LEED for Neighborhood Development. Water related aspects of both systems are discussed on basis of research in sustainable urban water management. Difficult questions raised in managing the urban water of the future are e.g. climate changes and new technical solutions for storm water management.

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47

Strand, Anders. "Urban Rain Water Harvesting and Water Management in Sri Lanka". Thesis, Malmö högskola, Fakulteten för teknik och samhälle (TS), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-20589.

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Denna fältstudie kommer att undersöka betydelsen av regnvattenanvändning som vattenförsörjnings alternativ. Hur kan hållbara innovativa lösningar tas fram för att lösa vattenförsörjningen på Sri Lanka? Efter lidandet av mer än 30 års inbördeskrig och efter de omfattande skadorna från tsunamin 2004, står nu Sri Lanka inför många utmaningar rörande landets återuppbyggnad. Tillgången till vatten är den viktigaste grundläggande förutsättningen för ett fungerande samhälle. I landets torra zon är det långa perioder av torka då vattenkällor sinar och inget naturligt vatten finns att tillgå. Detta trots att det under monsunen kommer tillräckligt med regn för att täcka vattenbehovet om det skulle samlas på ett optimalt sätt. Avrinningskoefficienten är här mer än 60% outnyttjat regnvatten. I ett flertal lyckade projekt har man samlat regnvatten i RWH system för senare användning. Människor i dessa områden saknar kranvatten eftersom detta område ej är täckt av vattenförsörjningsnätet. Detta gör att dessa människor har en positiv inställning till att ha RWH system..I den våta zonen, och då speciellt i Colombos stadsmiljö som denna studie handlar om, är situationen annorlunda. Här har de flesta invånare kranvatten. Det kommunala kranvattnet är högt subventionerat av regeringen vilket gör att kostnaden är låg för användarna samt ökar vattenkonsumtionen. Invånarna känner inget ansvar för vattenresurserna eftersom den gemena uppfattningen är att det är en evig källa. Majoriteten av hushållen ser inget skäl till att installera RWH på grund av den låga lönsamheten. Trots att det finns ett förordnande att det ska ingå ett RWH system, så följs inte detta. Saknande av uppföljningsplikt anges som orsak av vatten styrelsen. Kostnaden för att behandla och leverera vatten till invånarna är väldigt hög och är mycket energi krävande. Det finns ett behov av enorma investeringar för att rusta upp och bygga ut både vattenverken och vattennätet för att klara av att möta det växande invånarantalet i Colombo området. Ett annat problem är att 40% av hushållen i Colombo saknar avloppsanslutning. De leder sitt avloppsvatten direkt eller efter en septi-tank ut i jorden eller havet.Om medvetenheten kring dessa frågor ökar, samt att förhållandet mellan kranvattnets kostnad och RWH justeras med ändringar i subventionerna, kunde en hållbar lösning på vattensituationen med såväl ekonomiska som miljövinster ske.Resultatet av denna studie är att RWH får ses som ett komplement när det gäller vattenförsörjningen för hushållens del. Fokus bör istället ligga på industrier, sjukhus, skolor, kommunala byggnader och andra byggnader med stora vattenbehov och med de största möjligheterna att uppnå optimalt resultat.Studien visar också på en hållbar lösning på avloppshanteringen. Den visar DWWT och dess fördelar.
The field study will investigate the importance of Rain Water Harvesting (RWH) as a water supply option. How can sustainable innovative solutions be developed to solve the water problem of Sri Lanka? Suffering from more than 30 years of civil war and damages after being struck by the tsunami 2004, Sri Lanka faces many challenges to recover and rebuilt the country. The access to water is the most important need for a civilization´s existence. In the dry zones of the island people suffer from long drought periods with dried up wells and no natural sources for water. However the rainfall during the monsoon, even in these areas, is more than enough to provide the water needs if properly collected, thus the run-off coefficient is more than 60%. Several projects with rain water harvesting in so called RWH systems have been implemented with success. Because these areas are not covered by the water supply net and therefore have no tap water, the people are very positive to having the RWH system. In the wet zones and especially in the urban environment of Colombo the situation is different. Here most of the people have treated pipe-borne tap water. The metered tap water is highly subsidized by the government which makes the cost low for the users and increases the water consumption. The citizens do not feel a responsibility to be careful with resources since the common opinion is that water is a never ending source. The majority of the households find no reasons for installing a RWH system because it´s low economic profits. Even if there is a legislation that demands all new buildings should have a RWH system not many households have installed these systems. However the cost to deliver and treat this water is very expensive for the government and demands a lot of energy. Huge investments need to be done in both the treatment plants and the pipe-line net to meet the growing population in Colombo area. Another problem is that 40% of the households today in Colombo have no sewage connection but lead their wastewater directly or after a septic tank into the ground or the sea. If the awareness regarding these concerns could be improved and the conditions between tap water costs and RWH be adjusted with changes in the subsidized system, a sustainable solution to the water situation in Colombo with both economic and environmental benefits could be found. The result from the case study is a recommendation about installing RWH as a complimentary source of water for the households. And investments in RWH systems should be focused to industries, hospitals, schools, municipal buildings and other public buildings with a high water demand and with the best possibilities for optimal results. Further the case study treats a sustainable solution to the sewage situation. It shows the Decentralized waste water treatment plant (DWWT) and its advantages.

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48

Horton, Justin. "The Flow of the Water: Contemporary American Realisms". Digital Archive @ GSU, 2011. http://digitalarchive.gsu.edu/communication_theses/67.

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"Realism" is one of the enduring theoretical problems of the cinema. This study aims to broaden the parameters of the term by focusing on an often overlooked strain of thought that flows throughout the work of a number of prominent and seemingly incongruous thinkers such as Bazin, Kracauer, Benjamin, Barthes, Buñuel, and others. Realism, I contend, is undergirded by something far more elusive and irrational than verisimilitude or social commentary. To demonstrate, I will examine a body of contemporary American films that I will cast—perhaps provocatively—as realist. I rely heavily upon Deleuze to discuss how free indirect discourse and the disjunction of sound and image open realism to an oneiric and/or intersubjective realm.

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49

Baddam, Rakhi Reddy. "Anaerobic Fermentation of Hemicellulose Present in Green Liquor and Hot Water Extracts to Carboxylic Acids". Fogler Library, University of Maine, 2010. http://www.library.umaine.edu/theses/pdf/BaddamRR2010.pdf.

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50

Tanwar, Vikas. "Bridging water demand-supply gap : through rainwater harvesting in public green spaces in Delhi, India". Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/32269.

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"Water is likely to become one of the limiting resources of the next century, as well as one with multiple often conflicting uses." UNCEO NY1994 Presently, at least 1.1 billion of the world's people - about one in five - do not have access to safe water. City of Delhi in India is facing acute water crisis with a current demand supply gap of 236 million gallon per day (MGD) which is expected to widen to 564 MGD by the year 2021.ln view of the growing water crisis, the main objective of the thesis is to look into ways of mitigating the water crises in Delhi by bridging the water demand supply gap using environmental friendly and sustainable methods such as rainwater harvesting in the public green spaces of the region. The thesis begins with a thorough investigation of the Hydrological cycle (natural and urban), contemporary and traditional methods of rainwater harvesting, methods of recharge, and geological, hydro-geological and meteorological data of Delhi region. The regional data is overlaid and analyzed to define priority action areas and a conceptual action plan is recommended for each area. To demonstrate its feasibility, specific study areas are identified in the most stressed zone and investigated across four different scenarios ranging from neighbourhood to regional scale and from minimum to maximum intervention. It is learned through this investigation that public green spaces of Delhi hold great potential in bridging the water demand-supply gap. There are a range of modern and traditional methods available to successfully implement rainwater harvesting projects in these areas. They are technically and financially feasible and can be adopted at various levels depending on the availability of resources. It is found that public green spaces of Delhi which account for about 19% of the total urban area can bridge the water demand-supply gap by a maximum of 12.5%. Cost of the interventions can be amortized within 3 years and there are direct financial and environmental benefits to the local residents. The harvested rainwater can also be successfully used to meet the irrigation demand of the public green spaces partially, resulting in further cost savings to the government.
Applied Science, Faculty of
Architecture and Landscape Architecture (SALA), School of
Graduate

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Tesi sul tema "Green water"

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