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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.
81

"Halfway Between Nobody Knows Where and Somebody's Starting Point". A History of the West End of Motrose County, Colorado

Hardcastle, John A. 01 May 1998 (has links)
The thesis contains interesting and relevant information concerning the impact of the mining and milling industry on communities located within a geographically, socially, politically, and economically defined area in southwestern Colorado. This area supplied a tremendous amount of radium, vanadium, and uranlum In successlve eras. The author focuses primarily on Uravan, and examines the town's role in the uranium procurement program during World War II. The study of Uravan also provides information on the social structure of a company-owned community. Also examined are the ways in which government policies affected these small communities, and the impacts of the mining and milling industry upon the environment and human health.
82

Debris-Flow Activity in Canyon of Lodore, Colorado: Implications for Debris-Fan Formation and Evolution

Martin, Jennifer A. 01 May 2000 (has links)
Large-scale characteristics of Ladore Canyon debris fans are dependent upon the bedrock and lithology of the mainstem and tributary canyons. The largest fans occur in the widest section of the mainstem canyon, which typically correlates with the location of large faults. The steepest fans are found at the mouths of tributaries where cliffs are formed by resistant lithologies. Smaller-scale fan characteristics are dependent upon the magnitude and frequency of events from the respective drainage basin, which is controlled primarily by climate. Three distinct deposit ages ( oldest, intermediate, youngest) were distinguished on individual fans and were tentatively correlated throughout the canyon based on observations of boulder weathering, boulder concentration, soil development, vegetation, and topography. During fall 1997 and late spring 1998, four debris flows aggraded fans in Ladore Canyon. The largest of the four events, Wild Mountain, deposited a 3,800-m2 fan in the mainstem canyon, significantly constricting the Green River. Three of the four debris flows occurred in drainages that had been burned by forest fires during summer 1996. The debris flows were initiated during rainfall events with precipitation totaling more than 3 cm. Events of this magnitude have rarely been recorded in the region during the period of record. Measurements from the Wild Mountain debris fan indicate that under current operating conditions of Flaming Gorge Dam, the Green River has a limited capacity to mobilize newly deposited debris-flow material; therefore, particles eroded from the fan face cannot replenish downstream gravel bars. High release discharges equivalent to the 1997 high releases from Flaming Gorge Dam have a greater potential to rework newly deposited debris fans. (155 pages)
83

Mining the Colorado Plateau: the Story of Calamity Mesa 1910-19

Godfrey, Lisa Pitcher 01 May 1991 (has links)
This thesis was written to outline the history of five stone houses, which have survived almost a century of mining activity. The houses are located on a barren mesa, called Calamity, in southwestern Colorado. This work was funded by the Bureau of Land Management, Department of the Interior, in order to explore the possibility of designating this site as a National Historic Site. Men and women lived and worked on this and the surrounding mesas for most of the twentieth century. The lives of the families, the men, women, and children who lived and worked on Calamity Mesa, provided the context for the entire period. These people formed nebulous communities on what could only be called a twentieth-century frontier. I used several methods for this study, including oral interviews with surviving miners and their families, company and government officials, mining engineers, and medical personnel involved in studies concerning the effects of radiation exposure. Government publications, local newspapers, and personal papers of several individuals were also researched. Through the use of these methods I further developed the history of the period, by focusing on Calamity Camp and the lives of the men and women who lived and worked there. The miners who came to Calamity Mesa extracted the carnotite ore from sandstone beds. Originally, miners searched for radium, desired for its illusory cure for cancer. Then they sought vanadium, which was used as a strengthening agent for steel during both world wars . Finally, their goal was uranium, a key component for the production of nuclear weapons and energy. The search for these minerals brought, many working class men and women to the Colorado Plateau. They brought their families to Calamity Mesa and lived in whatever shelter they could find. The stone houses, lived in by generation after generation of miners and their families, who came searching for carnotite, provided a permanence to Calamity Mesa throughout this period.
84

"Evaluación hidroquímica y desarrollo de sistemas embebidos para la determinación de contaminantes en aguas naturales de la zona del valle inferior del río Colorado"

Vallese, Federico Danilo 08 July 2022 (has links)
La contaminación ambiental es una problemática a nivel mundial, particularmente la contaminación del agua que provoca el deterioro del ecosistema acuático. El estudio de los recursos hídricos es uno de los temas más relevantes dentro de la agenda ambiental de todos los países. La perturbación en el ciclo hidrológico y la contaminación incontrolada de los cuerpos de agua superficiales, provoca la atención de diversos organismos nacionales e internacionales para que destinen gran parte de su presupuesto al estudio de los recursos hídricos. Argentina no es ajena a esta problemática mundial y en su territorio existen cuencas hidrográficas con graves problemas de contaminación y escasez hídrica. La cuenca del río Colorado es la primera y única interprovincial de la Argentina que cuenta con un acuerdo de distribución de caudales, altamente significativo. El río Colorado atraviesa cinco provincias, siendo la zona de la cuenca inferior la correspondiente a la provincia de Buenos Aires. Debido a la naturaleza árida de los territorios que recorre, representa un recurso muy valioso para el desarrollo económico y social de la región, sirviendo en muchas ocasiones como única fuente de agua disponible para consumo humano, aseo, riego e industrias. Por ello, este trabajo de Tesis Doctoral está orientado al estudio de las características hidroquímicas y al desarrollo de sistemas embebidos para la determinación de contaminantes, en aguas naturales de la zona del Valle Inferior del río Colorado. La presente Tesis es un trabajo que se encuadra dentro de un Convenio Marco de carácter interdisciplinario (UNS, INTA, CIC-Buenos Aires y CORFO), enfocado a promover el desarrollo de la investigación y llevar a cabo estudios tendientes a mejorar la eficiencia del aprovechamiento del agua y preservación del recurso hídrico en el Valle Bonaerense del río Colorado. En tal sentido, los trabajos se desarrollan teniendo en cuenta los lineamientos de dicho Convenio: ✓ Caracterización y evaluación hidroquímica en la zona del Valle Bonaerense del río Colorado, con la finalidad de realizar una evaluación estadística hidrológica temporal que permita establecer las características actuales del sistema. ✓ Desarrollo de nuevas metodologías analíticas basadas en adquisición de datos de segundo orden provenientes del empleo de imágenes digitales, para la determinación de arsénico en muestras de aguas del Valle Bonaerense del río Colorado. ✓ Estudio de bioacumulación de cadmio y plomo en peces Cyprinus carpio, especie predominante en la región, que actúan como bioindicadores de contaminación. Las determinaciones de estos metales se realizan empleando un sistema automático Flow-batch y voltamperometría de redisolución anódica de onda cuadrada con un electrodo de film de bismuto como técnica de detección
85

Coleomegilla maculata (DeGeer) predation on eggs of Colorado potato beetle, Leptinotarsa decemlineata (Say).

Hazzard, Ruth V. 01 January 1989 (has links) (PDF)
No description available.
86

Biochemical factors of resistance and management of Colorado potato beetle, Leptinotarsa decemlineata (Say), (Coleoptera: Chrysomelidae).

Gouamene Lamine, Christiane N. 01 January 1994 (has links) (PDF)
No description available.
87

Evolutionary Aspects of Huerfano Butte Colorado

Durant, Dolores G. 04 1900 (has links)
<p> Gabbroic dyke and syenitic plug intrusives have been sampled and studied across Huerfano Butte. Petrography and geochemical analyses were performed on selected specimens; from these analyses chemical variation diagrams have been prepared. Crystal Size Distribution analyses have been done on magnetites and olivines to determine crystal nucleation and growth rate in the dyke. These data have been used to infer aspects of the evolution of Huerfano Butte.</p> / Thesis / Bachelor of Science (BSc)
88

The relationship of free amino acids of some solanaceous plants to growth and development of Leptinotarsa decemlineata (Say) /

Cibula, Adam B. January 1965 (has links)
No description available.
89

Efectos de la represa Casa de Piedra en la variación témporo espacial de las características hidrológicas y del diseño de drenaje del Río Colorado

Cazenave, Héctor Walter 12 December 2011 (has links)
El río Colorado se ubica en la parte Norte de la Patagonia argentina y atraviesa con dirección Oestenoroeste - Sur-sureste un sector del país de condición árida y semiárida ubicado entre la Cordillera de los Andes y el océano Atlántico, con un recorrido cercano a los 1.000 km. Esta tesis doctoral aborda el estudio de las características hidrológicas y el estudio específico de las variaciones en el diseño de drenaje de un tramo testigo ubicado en un área predeterminada por su cartografía secuencial y fiable en relación con las posibles variaciones hidrogeomorfológicas. Dentro de la problemática general que presenta el río Colorado, se tuvo en cuenta la función del río Curacó, último tramo de la gran cuenca Desa-guadero Salado Chadileuvú, a la que le da carácter de exorreica. Las periódicas activaciones del Curacó crean serios problemas de salinidad en las cuencas media y baja del Colora-do, parcialmente mitigados en la actualidad por la represa Casa de Piedra. El levantamiento del dique Casa de Piedra, sobre la parte final del alto valle, alteró drásticamente el comportamiento del río en cuanto al arrastre de sólidos. Por acción de su gran embalse se produce la deposición del mate-rial trasportado en suspensión, dándole una nueva condición física -y en parte también química- a las aguas emergentes del dique, que han dejado en el lago las arcillas y el limo que trasportaban. Esos materiales, antes de existir el dique, se depositaban aguas abajo e impermeabilizaban naturalmente los canales en las áreas de regadío de los valles medio e infe-rior. El agua que vierte Casa de Piedra, casi carente de sedi-mento, tiene una capacidad erosiva mayor que la que fluye antes del embalse; esa condición permite reducir el tiempo de formación de meandros con respecto a sectores de aguas arriba de la presa. Esas condiciones han generado también el fenómeno conocido como aguas claras. El estudio ordena en el tiempo y el espacio las variaciones de curvas y meandros del tramo testigo, cuantificándolas. Aunque también se han visto alteradas las curvas de caudal y salinidad es en el gasto sólido donde el dique Casa de Piedra ha provocado los cambios más visibles y fundamentales en el ser y quehacer del río. La curva resultante de los nuevos valores refleja la situa-ción con respecto a la anterior y marca una fuerte disminu-ción en el acarreo. Esta tesis es además un aporte a poste-riores investigaciones interdisciplinarias, especialmente en el campo de la hidráulica y la geomorfología fluvial, dos disci-plinas bajo las cuales el río Colorado ofrece un amplio campo de estudios. El trabajo detecta, determina y cuantifica los cambios físicos y humanos generados por la presencia del dique, algunos ya evidentes y otros en trance de serlo. / The construction of Casa de Piedra dam, in the final stretch of Colorado river high valley, radically modified down waters the hydrologic river course, specially as regards sediment transport, the majority of which settles in the lake. Conse-quently, waters the dam distributes, contain a remarkable erosive capacity, and accelerate down waters hydrographic processes, increasing river meandering and bringing about what is known as the clear waters phenomenon causing adverse effects on watering zones. With the purpose of checking the fact in a quantitative way, cartographies from a certain stretch were taken, being this stretch considered a witness one in periods around 25 years, assessing meanders appearance and disappearance, and comparing these quantities with the variation -in the same sense-, that took place since Casa de Piedra start up. The quantities were sig-nificant considering the relatively short time gone by. The fact was checked in a new aero - photographic flight, according to which, in a shorter lapse, meanders number increased again in the witness stretch.
90

Path Dependence in Colorado's Renewable Portfolio Standards

Rivera, Alex M. 03 June 2022 (has links)
Renewable Portfolio Standards (RPS) have been a staple energy policy in the state of Colorado since 2004. While there has been a steady increase to the RPS percentages over the years, there have been several points where this policy has been significantly contested. This paper explores the political decision making of the two largest electricity producers in the state, Xcel Energy and Tri-State Generation and Transmission Association, to determine at what points that the costs of legislation exceeded the costs of opposition for those two organizations. Using this information, the paper explores the implications these political battles have on characterizing Colorado as a state with renewable path dependency and renewable policy feedback. / Master of Arts / Since 2004, Colorado has enacted several successful laws to increase renewable energy use within the state. However, in recent years these laws have failed to achieve their goals. By analyzing the two largest producers of electricity in the state, Xcel Energy and Tri-State Generation and Transmission Association, this paper tries to answer what parts of the policies were too costly for the organizations to accept. Using this information, this project concludes that the current renewable energy policies are unlikely to be repealed in the future, but there is some evidence to suggest that the rate of renewable energy policy enactment may decrease.

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