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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.
141

Improved ground-gas risk prediction using in-borehole gas monitoring

Nwachukwu, Arthur Nwachukwu January 2014 (has links)
Elevated concentrations of ground-gases (CH4 and CO2) and VOCs in contaminated soil and water around the world pose significant risk both to human health and the environment. There is, therefore, a requirement to monitor them for effective risk assessment and remediation. Current ground-gas monitoring is often ineffective for determining their representative concentrations and fluxes – the two most important parameters necessary for ground-gas risk assessment. These failures of current monitoring may arise from its low temporal resolution. The recent ability to monitor at high temporal resolution – using Gasclam - makes it possible to determine whether this is the case and whether high resolution monitoring can be more effective. CH4 and CO2 were monitored at several sites using Gasclam. This showed that in many cases concentrations were sufficiently variable that current sampling practices would be ineffective at detecting worst case concentrations. Furthermore, the time-series data produced by Gasclam allowed the predictive power of the established relationships between atmospheric pressure and gas concentration to be improved. The failures in the relationship could also be understood as hysteresis which gave an index of ground permeability and/or gas generation. These improvements in understanding could be used to improve the conceptual site models on which risk assessments are based. Similarly, high temporal resolution VOC measurement demonstrated the need for such measurement. The factors controlling VOC concentration were shown to be same to those controlling ground-gases; again this understanding of process would also improve the conceptual site model. A monitoring method that incorporated parallel non-specific real time measurement with a time integrated VOC measurement that identified specific VOC’s was tested. The method was an improvement on the separate methods as it could be used to reasonably infer the concentrations of specific VOC’s at high temporal resolution. The ability to monitor gas concentrations at high temporal resolution gave the potential for the rate of gas concentration recovery subsequent to purging of the borehole to be used as an index of gas flux. These tests proved to be practical, generally taking less than the time of a site visit, and reproducible. Variability in these recovery profiles was assessed at different sites, times and for different gases.
142

The propagation and culture of Mitchella repens L.

Snow, Samuel Peaslee 01 January 1950 (has links) (PDF)
No description available.
143

Radiohm mapping of permafrost

Powell, Brian W. January 1978 (has links)
No description available.
144

Playable Ground

Weaver, MaryKate Olson 06 July 2015 (has links)
Playing outside is of vital importance to children's mental and physical health; play is a biological necessity that teaches children the skills they will need in order to survive as adults. Yet the colorful and ubiquitous playground structures found in most parks often fall short of their full potential. These plastic playgrounds, which should serve as catalysts for creative thought and action in children, are limited in their sameness. Furthermore, the playground structures, which are manufactured in bulk and then bolted onto the ground at their final destinations, have little connection to their sites. I propose to investigate the characteristics of playgrounds in Washington, DC, and to use this investigation as a catalyst in the creation of a different type of grounds for play. I will create a playable ground which utilizes the specific qualities of site to engage children to move their bodies and their minds in imaginative ways. / Master of Landscape Architecture
145

Caracterização física, química, mineralógica e morfológica de uma sequência de solos em Lins/SP. / Physical, chemical, mineralogical and morphological characterization of a soil series in Lins/sp.

Ibrahim, Liliane 08 March 2002 (has links)
Este trabalho tem como objetivo a caracterização de um sistema de solos, evidenciando os parâmetros que possam esclarecer sua dinâmica e contribuir para a definição de critérios que possam determinar a aptidão destes solos como receptores de efluentes. Trata-se de uma área experimental de estudos, contígua à Estação de Tratamento de Esgoto do município de Lins (SP), onde efluentes são gerados a partir do tratamento de esgoto por sistema de lagoas de estabilização. Nesta área, vem sendo aplicada a técnica de irrigação com efluentes (fertirrigação). Os solos, situados ao longo de uma vertente com ligeira inclinação, foram caracterizados através de análises morfológicas, granulométricas, químicas, mineralógicas e micromorfológicas, realizadas em amostras coletadas em seis trincheiras abertas ao longo de duas topossequências, dispostas segundo o eixo de maior declive da vertente. Os solos são desenvolvidos a partir dos sedimentos arenosos da Formação Adamantina (Grupo Bauru) e constituem um sistema Latossolo - Argissolo, onde a transição Bw - Bt ocorre lateralmente do topo para a base da vertente. Foram identificadas quatro fases pedogenéticas nesta associação de solos. As duas primeiras, argiluviação e adensamento de partículas, responsáveis pela formação dos horizontes texturais, foram superpostas pelos processos de latossolização e hidromorfismo, atuantes na dinâmica atual destes solos. Análises micromorfológicas mostraram tratar-se de solos com intensa porosidade, caracterizada pelo empilhamento dos grãos do esqueleto quartzoso, amplamente predominante, e pelo arranjo entre os microagregados granulares. A permeabilidade é ainda favorecida pela intensa ação da mesofauna. Os solos são distróficos, com alta saturação por alumínio e compostos por caolinita e óxidos de ferro. Por se constituirem num sistema frágil, a disposição de quaisquer tipos de resíduos nestes solos, requer o monitoramento constante de suas propriedades, tanto para a manutenção, quanto para a recuperação da qualidade desta cobertura pedológica. / The purpose of this study is to characterize a soil system, identifying the properties which can elucidate its dynamics and to define criterions for the ability of these soils to constitute an effluent disposal land. The experimental area is located nearby the Sewage Treatment Station (STS), in Lins (SP) and the effluent is proceeded for secundary treatment. In this area, is being applied the technique of fertirrigation. The soils are situated on a downslope and were characterized beside morphological, particle size, chemicals, mineralogicals and micromorphologicals analyses on samples collected in six profiles along two toposequences, across the axis of maximun gradient on downslope. These soils are expanded from sandstones of Adamantina Formation (Bauru Group) and compose an Oxisol-Ultisol system. The Bw-Bt transition accurs laterally, from the upper to the lowest part of downslope. It was recognized four pedogenetic phasis. Both first, argilluviation and compressed layer, explain the formation of argillic horizons and were superimposed from latossolization and hydromorphism, both last actuating on the actual dynamics of these soils. Micromorphological analysis showed that these soils are too porous, characterized for packing of skeletic grains and between granular aggregates. The permeability is increased by the activity of mesofaunal. These soils are dystrophics, have high aluminium saturation and are composed for kaolinite and iron oxides. This system is fragile, thus, the deposal of any kind of residues on these soils, needs the constant warning of all of their properties, so to the maintenance and also the recover of the quality of this pedologic cover.
146

Caracterização física, química, mineralógica e morfológica de uma sequência de solos em Lins/SP. / Physical, chemical, mineralogical and morphological characterization of a soil series in Lins/sp.

Liliane Ibrahim 08 March 2002 (has links)
Este trabalho tem como objetivo a caracterização de um sistema de solos, evidenciando os parâmetros que possam esclarecer sua dinâmica e contribuir para a definição de critérios que possam determinar a aptidão destes solos como receptores de efluentes. Trata-se de uma área experimental de estudos, contígua à Estação de Tratamento de Esgoto do município de Lins (SP), onde efluentes são gerados a partir do tratamento de esgoto por sistema de lagoas de estabilização. Nesta área, vem sendo aplicada a técnica de irrigação com efluentes (fertirrigação). Os solos, situados ao longo de uma vertente com ligeira inclinação, foram caracterizados através de análises morfológicas, granulométricas, químicas, mineralógicas e micromorfológicas, realizadas em amostras coletadas em seis trincheiras abertas ao longo de duas topossequências, dispostas segundo o eixo de maior declive da vertente. Os solos são desenvolvidos a partir dos sedimentos arenosos da Formação Adamantina (Grupo Bauru) e constituem um sistema Latossolo – Argissolo, onde a transição Bw – Bt ocorre lateralmente do topo para a base da vertente. Foram identificadas quatro fases pedogenéticas nesta associação de solos. As duas primeiras, argiluviação e adensamento de partículas, responsáveis pela formação dos horizontes texturais, foram superpostas pelos processos de latossolização e hidromorfismo, atuantes na dinâmica atual destes solos. Análises micromorfológicas mostraram tratar-se de solos com intensa porosidade, caracterizada pelo empilhamento dos grãos do esqueleto quartzoso, amplamente predominante, e pelo arranjo entre os microagregados granulares. A permeabilidade é ainda favorecida pela intensa ação da mesofauna. Os solos são distróficos, com alta saturação por alumínio e compostos por caolinita e óxidos de ferro. Por se constituirem num sistema frágil, a disposição de quaisquer tipos de resíduos nestes solos, requer o monitoramento constante de suas propriedades, tanto para a manutenção, quanto para a recuperação da qualidade desta cobertura pedológica. / The purpose of this study is to characterize a soil system, identifying the properties which can elucidate its dynamics and to define criterions for the ability of these soils to constitute an effluent disposal land. The experimental area is located nearby the Sewage Treatment Station (STS), in Lins (SP) and the effluent is proceeded for secundary treatment. In this area, is being applied the technique of fertirrigation. The soils are situated on a downslope and were characterized beside morphological, particle size, chemicals, mineralogicals and micromorphologicals analyses on samples collected in six profiles along two toposequences, across the axis of maximun gradient on downslope. These soils are expanded from sandstones of Adamantina Formation (Bauru Group) and compose an Oxisol-Ultisol system. The Bw-Bt transition accurs laterally, from the upper to the lowest part of downslope. It was recognized four pedogenetic phasis. Both first, argilluviation and compressed layer, explain the formation of argillic horizons and were superimposed from latossolization and hydromorphism, both last actuating on the actual dynamics of these soils. Micromorphological analysis showed that these soils are too porous, characterized for packing of skeletic grains and between granular aggregates. The permeability is increased by the activity of mesofaunal. These soils are dystrophics, have high aluminium saturation and are composed for kaolinite and iron oxides. This system is fragile, thus, the deposal of any kind of residues on these soils, needs the constant warning of all of their properties, so to the maintenance and also the recover of the quality of this pedologic cover.
147

Above and Below Ground Assessment of Pinus radiate

McQuillan, Shane January 2013 (has links)
A comparison of above ground forest metrics with below ground soil CO₂ respiration was carried out in an attempt to reveal if any correlations exist. Above ground measurements of 2720 clonally propagated trees were taken assessing the silvicultural treatments of stocking, herbicide and fertiliser. These were compared to 480 below ground soil CO₂ respiration measurements. Using measurements of mean height, mean dbh and basal area the data was analysed and returned significant results for mean dbh and the interactions of herbicide and clones, and stocking and herbicide. Mean height returned a significant result for the interaction of stocking and herbicide. Below ground measurements showed an interaction between ripping and stocking; however these results were not ratified by the above ground results. Overall the results were encouraging and should aid in future experiments that seek to understand what effect above ground treatments have on below ground CO₂ activity.
148

An Experimental Analysis of the Alarm Calls of Captive Uinta Ground Squirrels (Spermophilus armatus)

Cherry, Marion Barch 01 May 1979 (has links)
This study investigated alarm calls given by Uinta ground squirrels (Spermophilus armatus) in the presence of a ground predator. I observed predator responses of 18 groups of three to four squirrels each for an average of three trials apiece. r~y objectives were: (1) to describe prey-predator interactions resulting in alarm calls, and (2) to test the following hypotheses: 1. Each Uinta ground squirrel (by sex and age) has an equal probability of giving an alarm call at any time of the season. 2. All Uinta ground squirrels are equally likely to call regardless of their distance to a burrow, closest conspecific, and the predator. 3. Alarm calls are as likely to occur in the search stage of predation as in the pursuit stage. 4. Callers and noncallers are equally vulnerable to predation. I found that: ( 1) each Uinta ground squirrel (by sex and age) in the experimental population had an equal probability of giving an alarm call in the presence of a predator through the season, (2) callers and noncallers were equally close to burrows at the time of the call, (3) the caller was typically located farther away from its closest conspecific than noncallers at the time of the cal l, (4) the caller was significantly closer to the predator than were noncallers at the time of the call, (5) alarm calls occurred significantly more often in the pursuit stage of predation than in the search stage, and (6) noncallers suffered significantly more predation than did callers. There appeared to be little risk and energetic cost associated with calling. Squirrels that called usually were being pursued by the predator and were very close to a burrow when they called. The callers had little to lose and could increase their inclusive fitness by warning relatives of the presence of danger. This study dealt only with responses to ground predators. Squirrels are likely to respond differently to avian predators. It is suggested that responses of animals to avian and terrestrial predators should vary with the potential threat that the predator poses. The apparent inhibition of secondary calls is discussed. Once animals are aware of the presence of danger, there is no need for another animal to repeat the message and reveal its location to the predator.
149

Experimental studies of electromagnetic signals to enhance radio imaging method (RIM)

Monaghan, William D. January 2007 (has links)
Thesis (M.S)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains xi, 104 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 69-70).
150

Improving success of translocating southern Idaho ground squirrels (Spermophilus endemicus) /

Busscher, Katie Lea. January 2009 (has links)
Thesis (M.S.)--Boise State University, 2009. / Includes abstract. Includes bibliographical references (leaves 41-45).

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