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

Motive importance based on trip outcome, experience level and group type related to whitewater paddling on the Nantahala River

Collins, Kimberly Anne. January 2007 (has links)
Thesis (M.S.)--Indiana University, 2007. / Includes bibliographical references (leaves 79-81).
2

An economic analysis of whitewater recreation on the upper Klamath River /

Moore, Eric M. January 1989 (has links)
Thesis (M.S.)--Oregon State University, 1990. / Typescript (photocopy). Includes bibliographical references (leaves 97-108). Also available on the World Wide Web.
3

Perceptions of ecotourism a case study of whitewater guides in the rural highlands of Fiji /

Beeftink, Karen. Unknown Date (has links)
Thesis (M. S.)--West Virginia University, 2004. / Includes bibliographical references (p. 215-223).
4

An investigation of flow and IZOF utilization of FSS-2

McCune, Joel D. January 2006 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (February 9, 2007) Includes bibliographical references.
5

“A promising little society”: Kinship and Community Among the White Water Shakers 1824-1850

Cummings, Lindy 09 August 2010 (has links)
No description available.
6

T-RFLP analyses of biocides influence on white water micro-organisms – planktonic and in biofilm

Bodin, Rebecka Unknown Date (has links)
<p>When paper is manufactured, deposits often form in the machines. These deposits are slimelike and can interfere with the papermaking process. The slimelike deposits are aggregates of micro-organisms, also known as biofilm. One single type of micro-organism can form a biofilm, but most biofilms consists of a mixture of several different kinds of micro-organisms and can form on about any conceivable surface. To control the aggregates of micro-organisms a slimecide is added, a so-called biocide. To examine what kind of bacteria that is included in the biofilm and also which bacteria that is killed or not killed by the biocide, Terminal Restriction Fragment Length Polymorphism analysis (T-RFLP) can be used.</p><p> </p><p>In this report we examine biocides impact on biofilm produced in the laboratory.The biocides were first tested for possible interference with the PCR-step of the T-RFLP analysis. None of the tested ten biocides inhibited the PCR process the biofilm was formed on metal plates when these were lowered in a beaker with white water. Three different beakers were set up, one with addition of a biocide with active component 4,5-DICHLORO-1,2-DITHIOLONE from the start, one with the addition of the same biocide after three days and one with no addition at all of biocide. Samples were taken from the beakers and analyzed with T-RFLP.</p><p> </p><p>In this report, we show that biocides affect planktonic and biofilm micro-organisms differently. There are however some micro-organisms in the biofilm that does not get affected by the biocide.</p><p> </p><p>The experimental in this report is a good way of investigate the influence that biocides have on planktonic and biofilm micro-organisms, but to get even greater result the experiment should be done over a longer period of time and repeatedly.</p>
7

The Influences on the Optical Properties of Paperboard Due to Dye Additives / Påverkan på de optiska egenskaperna hos kartong till följd av tillsats av färgämne

Wallmon, Tanya January 2019 (has links)
In the paper industry the appearance and optical performance of coated and uncoated paperboard is important, therefore colour dyes are widely used to enhance the paperboard. In order to enhance the appearance of paper products, the dyes are added directly into the pulp and/or in the coating. This addition can lead to dye buildup in the white water system. The white water system recirculates back to the pulp and contains both chemicals, dye and fibers. A general assumption is, when the concentration of dyes builds up in the system, it can lead to changes of the optical properties. Previously studies have been conducted to investigate the white water system at Iggesund Paperboard Workington Ltd. mill. Suspicion of a potential dye buildup in the white water system arose because of notable changes in the optical properties of the collected samples. An assumption was, when the concentration of dye increases in the white water system, it led to changes of the optical properties. The purpose of this project was therefore to investigate if/how potential dye buildup occurred in the white water system at Iggesund paperboard Workington Ltd. Mill. The system will be analyzed for dye buildup and to see if it influences the optical properties of the coated paperboard as a final product as well as how quickly it builds up in the system. This report contains a theoretical background for relevant knowledge about the white water system and optical properties of paperboard. The methodology for this project was to collect samples from the boardmachines’ white water system and analyze them through laboratory trials. Collected data is presented in the form of diagrams, trends have been investigated to validate assumptions. The dye dosage point was also analyzed through laboratory trials, to confirm or deny whether it is possible to achieve an optimal dosage point. The analysis showed that there were changes in the optical properties in the white water over time, as a result of dye buildup. Due to the complex system and different parameters that may affect the system, the sample collection needs to be extended further for a more precise conclusion. Such as how the dye responds to longer shuts and addition of polymers. Apart from what influenced the optical changes in the white water system and may have affected the paperboard, when the top coating from the production is applied, no changes or variations cannot be seen. Therefore giving the conclusion, that the changes of the optical properties do not influence the paperboard as a final product. / Kartong är bland de vanligaste materialen att använda vid paketering. Den optiska egenskapen hos kartong är viktig för att den ska se tilltalande ut, samt vara mottaglig för tryck. Användning av färg är vanligt förekommande inom pappersindustrin för att förbättra de optiska egenskaperna i obelagt papper och belagt papper. Färgen tillsätts vanligen direkt i pappersmassan och vid bestrykning av beläggningen. Dock kan det leda till övermättnad i bakvattnet när man tillsätter färgen direkt i massan, vilket i sin tur kan påverka och även förändra de optiska egenskaperna. Bakvattnet recirkuleras i processen tillbaka till massaflödet då vattnet fortfarande innehåller användbara kemikalier, färg och fibrer som kan ansluta sig till massaflödet igen. Skulle det ske förändringar av de optiska egenskaperna behöver doseringen av färgen förändras vid beläggningen, vilket i sin tur kan leda till överdosering av färgen. Tidigare studier gällande bakvattensystemet vid Iggesund Paperboard Workington Ltd. mill har gjorts. Förändringar i de optiska egenskaperna från samlade prover från bakvattnet resulterade i misstankar av en potentiell ökning av färg i systemet. Detta utmynnade i antagandet att den ökande koncentrationen av färg i bakvattensystemet, i slutändan orsakar optiska förändringar. Syftet med detta projekt var därför att undersöka denna potentiella färgökning i bakvattensystemet vid Iggesund paperboard Workington Ltd. Mill. Bakvattensystemet har analyserats för att se en ökad färgkoncentration och om dessa optiska förändringar påverkar slutprodukten, samt hur snabbt färgens koncentration ökar. Denna rapport innehåller en teoretisk bakgrund för bland annat bakvattensystemet samt de optiska egenskaperna hos kartong. Metodiken för projektet var att samla prover från kartongmaskinens bakvattensystem och att analysera dessa prover. Insamlad data presenteras i diagram och trender undersöktes, för att validera antaganden modellerades trender. Doseringen av färgen undersöktes genom försök, för att kunna bekräfta om det är möjligt att upptäcka en optimal doseringspunkt. Analyserna visar att det sker förändringar i dem optiska egenskaperna över tid, som ett resultat av en ökad koncentration av färg. Då systemet är komplext och olika parametrar kan ha påverkat, behöver denna undersökning förlängas för en säkrare slutsats. Till exempel hur långa stop och hur addition av polymerer påverkar processen. Bortsett från vad som påverkar de optiska förändringarna i bakvattnet och kan påverka slutprodukten, när kartongen bestryks med beläggning, kan inga förändringar/variationer ses. Därför ges slutsatsen, att förändringar i de optiska egenskaperna i bakvattnet inte påverkar kartongen som slutprodukt.
8

Simulating the effects of dam releases on Grand Canyon river trips

Borkan, Ronald E., January 1986 (has links) (PDF)
Thesis (M.S. - Renewable Natural Resources)--University of Arizona, 1986. / Includes bibliographical references (leaves 78-80).
9

Material aderido à macrófitas aquáticas submersas enraizadas com arquiteturas de ramo distintas e em diferentes tipos de água / Attached material on rooted submerged aquatic macrophytes with distinct branch architectures and in different types of water

Silveira, Aline Flores [UNESP] 15 February 2018 (has links)
Submitted by Aline Flores Silveira null (fsaline@hotmail.com) on 2018-02-28T17:46:28Z No. of bitstreams: 1 Versão final_Aline Flores _Silveira_Mestrado.pdf: 1033383 bytes, checksum: 0348b6e859d4559a1fc2c3b3d311cc7c (MD5) / Approved for entry into archive by Ana Paula Santulo Custódio de Medeiros null (asantulo@rc.unesp.br) on 2018-03-01T11:49:57Z (GMT) No. of bitstreams: 1 silveira_af_me_rcla.pdf: 1031556 bytes, checksum: 27cd24178827289f17b4d42db2e285d4 (MD5) / Made available in DSpace on 2018-03-01T11:49:57Z (GMT). No. of bitstreams: 1 silveira_af_me_rcla.pdf: 1031556 bytes, checksum: 27cd24178827289f17b4d42db2e285d4 (MD5) Previous issue date: 2018-02-15 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Uma forma de compreender e caracterizar a importância ecológica das macrófitas aquáticas é através do delineamento das diferenças morfológicas das plantas e da quantificação de sua complexidade. As macrófitas podem atuar como estruturas retentoras de partículas em suspensão controlando a quantidade de material em suspensão na água, além de servirem como substrato para a colonização e crescimento do perifíton. Neste estudo foram utilizadas duas macrófitas aquáticas: Cabomba furcata Schult. & Schult. e Egeria densa Planch, encontradas na Bacia Hidrográfica do Rio Itanhaém. O objetivo geral foi avaliar se a capacidade de retenção de material varia entre macrófitas aquáticas com arquitetura de ramo distintas e se há variação na capacidade de retenção de material de C. furcata em rios com características limnológicas distintas. A coleta foi realizada em duas áreas no Rio Branco (A e B) e uma área no Rio Preto (C). Amostras de água e sedimento foram coletadas para análises limnológicas. Ramos de C. furcata e E.densa no Rio Branco e ramos de C. furcata no rio Preto foram coletados para a descrição de sua arquitetura e para a quantificação do material aderido. Em laboratório foram realizadas análises das variáveis limnológicas e do conteúdo de nitrogênio e fósforo total na biomassa das macrófitas e no material aderido. Para a caracterização ambiental das áreas de coleta, foram comparados os resultados das variáveis limnológicas medidas em cada área estudada. Para testar a diferença significativa entre as áreas A e C, foi aplicado o teste-t (p<0,05) às variáveis limnológicas. O teste Mann-Whitney foi aplicado às variáveis de C. furcata, E. densa e às variáveis do material aderido coletadas no Rio Branco. O mesmo teste foi utilizado para a comparação entre C. furcata e material aderido em rios distintos. Os valores das variáveis limnológicas do Rio Branco foram similares nas áreas A e B. A quantidade de material em suspensão na água foi maior (p<0,001) no Rio Branco quando comparado ao Rio Preto. Porém, a matéria orgânica contida no sedimento do Rio Branco foi menor (p: 0,005) do que a contida no sedimento do Rio Preto. Por outro lado, os teores de nitrogênio e fósforo total da água e do sedimento não apresentaram diferença significativa. C. furcata e E.densa apresentaram diferenças na arquitetura do ramo (p<0,05), indicando uma maior complexidade do ramo para C. furcata. C. furcata de rios distintos apresentou pequenas variações na sua morfologia. Apesar da C. furcata apresentar maior área total do ramo do que E. densa, a quantidade de material aderido por ramo de C. furcata foi menor (p: 0,001). A quantidade de material aderido à C. furcata no Rio Branco foi menor (p:0,0251) do que à C. furcata no Rio Preto. De modo geral, a quantidade de material aderido às macrófitas em ambientes lóticos pode ser positiva, negativa ou neutra às macrófitas e pode estar associada à complexidade da arquitetura do ramo desses organismos. Todavia, neste estudo a relação entre as espécies de macrófitas aquáticas avaliadas e o material aderido é neutra. Desta maneira, essas espécies podem ser consideradas apenas como um substrato para o acúmulo de material aderido, pois não foram encontradas relações positivas ou negativas com esse material. / One way to understand and characterize the ecological importance of aquatic macrophytes is to delineate the morphological differences of plants and quantify its complexity. Aquatic macrophytes can act as suspended particulate retentive structures by controlling the amount of suspended material on the water and serve as a substrate for the colonization and growth of the periphyton. Two aquatic macrophytes were used in this study: Cabomba furcata Schult. & Schult. and Egeria densa Planch, bouth are found in the Itanhaém River Basin. The aim of this research was to evaluate if the retention capacity of material varies between aquatic macrophytes with different branch architecture and if there is variation in the material retention capacity of Cabomba furcata in rivers with different limnological characteristics. The sample were collected in two areas in Branco River (A and B) and one area in Preto River (C). Water and sediment samples were collected for limnological analysis. C. furcata and E. densa branches were collected in Branco River for the description of the branch architecture and for the quantification of the attached material. In the same way, branches of C. furcata were collected in Preto River for the same purpose. In laboratory, analyzes of the limnological variables, the nitrogen and total phosphorus content in the macrophytes biomass and the attached material were performed. For the environmental characterization of the study areas, the results of the limnological variables measured in each studied area were compared. To test the significant difference between areas A and C, the t-test (p <0.05) was applied to the limnological variables. The Mann-Witney test was used for the variables of C. furcata, E. densa and attached material collected in Rio Branco. The same test was applied for the comparison between C. furcata and attached material from different rivers. The values of the limnological variables of Branco River were similar in areas A and B. The amount of suspended material in water was higher (p <0.001) in Branco River when compared to Preto River. However, the organic matter contained in Branco River sediment was lower (p: 0.005) than the one contained in Preto River sediment. On the other hand, nitrogen and total phosphorus contents of water and sediment did not present a significant difference. C. furcata and E. densa presented differences in the branch architecture (p <0.05), indicating a greater branch complexity for C. furcata. C. furcata of distinct rivers showed small variations in its morphology. Although C. furcata had a larger branch total area than E. densa, the amount of attached material per branch of C. furcata was lower (p: 0.001). The amount of attached material to C. furcata in Branco River was lower. In general, the amount of attached material on the macrophytes in lotic environments may be positive, negative or neutral to the macrophytes and may be associated with the complexity of the macrophytes architecture. However, in this study, the relationship between the species of aquatic macrophytes evaluated and the attached material is neutral, so that these species can only be considered as a substrate for the accumulation of attached material, not having a positive or negative relation with this material. / CNPq: 130835/2016-1
10

T-RFLP analyses of biocides influence on white water micro-organisms – planktonic and in biofilm

Bodin, Rebecka Unknown Date (has links)
When paper is manufactured, deposits often form in the machines. These deposits are slimelike and can interfere with the papermaking process. The slimelike deposits are aggregates of micro-organisms, also known as biofilm. One single type of micro-organism can form a biofilm, but most biofilms consists of a mixture of several different kinds of micro-organisms and can form on about any conceivable surface. To control the aggregates of micro-organisms a slimecide is added, a so-called biocide. To examine what kind of bacteria that is included in the biofilm and also which bacteria that is killed or not killed by the biocide, Terminal Restriction Fragment Length Polymorphism analysis (T-RFLP) can be used.   In this report we examine biocides impact on biofilm produced in the laboratory.The biocides were first tested for possible interference with the PCR-step of the T-RFLP analysis. None of the tested ten biocides inhibited the PCR process the biofilm was formed on metal plates when these were lowered in a beaker with white water. Three different beakers were set up, one with addition of a biocide with active component 4,5-DICHLORO-1,2-DITHIOLONE from the start, one with the addition of the same biocide after three days and one with no addition at all of biocide. Samples were taken from the beakers and analyzed with T-RFLP.   In this report, we show that biocides affect planktonic and biofilm micro-organisms differently. There are however some micro-organisms in the biofilm that does not get affected by the biocide.   The experimental in this report is a good way of investigate the influence that biocides have on planktonic and biofilm micro-organisms, but to get even greater result the experiment should be done over a longer period of time and repeatedly.

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