Patterning and Characterization of Carbon Nanotubes Grown in a Microwave Plasma Enhanced Chemical Vapor Deposition Chamber

This research studies the growth of carbon nanotubes (CNT) from a nickel catalyst to be used on a field emission device. This thesis can be divided into three sections: the construction of a vacuum chamber for field emission testing, the design and fabrication of a triode structure to enable improved electron emission, and the pretreatment and growth of CNTs. To experimentally test the field emission of CNTs, a vacuum chamber must attain a vacuum of at least 10-5 torr. Our vacuum chamber designed and built achieved a maximum, final pressure of 10-8 torr. A triode structure was designed to pattern the CNTs to improve electron emission. A silicon wafer is used to fabricate the cathode and gate of the device while a quartz wafer is used as the anode. Through photolithography patterning of the gate, CNT growth occurs only in the defined locations. To better understand CNT growth, a study was performed using a hydrogen pretreatment on sputtered and electroplated nickel catalyst on silicon at various thickness in a microwave plasma enhanced chemical vapor deposition to determine the effects of this pretreatment. Nickel catalyst of 50, 100, and 200 ºA were treated with hydrogen and the formation of nano islands was achieved when using sputtered films. As the nickel catalyst thickness increases, the pretreatment time must also be increased to get favorable granule sizes and densities necessary for CNT growth. The 50 and 100 ºA nickel samples granulated to 25 and 58 nm showed high growth densities while the 200 ºA samples granulated to 180 nm showed marginal CNT growth. We also established the diameter of the multi walled CNTs grown correlated well to the size of the catalyst granules. The CNTs to be used in the triode design needed to be between 1.5 and 1.8 µm to avoid shorts between the gate and the CNTs. To achieve this, CNTs with a length of 1.5 µm were successfully grown by flowing methane for exactly two minutes

A Study of Professional Burnout in Bay Area Mental Health Agencies

This study broadened the focus of staff burnout research by analyzing organizational perspectives to augment the staff perspectives presented in current research. Managers of mental health organizations in the Bay Area were surveyed for their perceptions of stress in their agencies, for their perceptions of the acceptable level of burnout among staff, and for their reports on the status of actual working conditions and benefits. Using discriminant function analysis, this study showed a statistically significant difference for two agency characteristics-annual budget level and turnover rate-when analyzed in conjunction with managers\u27 perceptions of the acceptable level of burnout. This study found that managers at mental health organizations perceived stress in their agencies as relating to organizational and external environment factors, such as uncertainty of funding, lack of leadership, and poor job design. Managers were aware of the impact that management and outside resources have on the levels of stress experienced in their agencies. This study also found that the majority of managers were interested in reducing burnout at their agencies. This study was unable to discover any distinction between existing agency coping mechanisms and managers\u27 perceptions of the acceptable level of burnout in their agencies. Based on these findings, implications for organizational response to staff burnout and suggestions for future research are discussed

The concept of civil society and the process of nation-building in African states

Paper presented at the Wits History Workshop: Democracy, Popular Precedents, Practice and Culture, 13-15 July, 199

The Late Weichselian to Holocene succession of the Niedersee (Rügen, Baltic Sea) – new results based on multi-proxy studies

Eine klassische weichselspätglaziale Lokalität ist die kleine Toteishohlform des Niedersees, welche direkt an der südöstlichen Küste der Halbinsel Jasmund (Rügen, Ostsee) aufgeschlossen ist. Neue Studien wurden durchgeführt, bei denen sich die sedimentäre Abfolge des Niedersees als ein hervorragendes Archiv für paläoökologische/-klimatische Rekonstruktionen erwies, wodurch detaillierte Aussagen zur regionalen Vegetationsgeschichte sowie zum regionalen Klima und Milieu während des Weichselspätglazials und auch teilweise für das Holozäns möglich sind. Mit Hilfe der Pollenstratigraphie, AMS 14C-Datierungen und dem Nachweis der Laacher See Tephra konnte die sedimentäre Abfolge in die bestehende Quartärstratigraphie eingehängt werden; als Besonderheit ist hier das quasi gesamte Weichselspätglazial vollständig aufgeschlossen. Die Sedimentation beginnt schon im ausgehenden Weichselhochglazial und dauert zunächst bis zum Präboreal an (~15.000–~10.000 Jahre v. H.) und ist vor allem durch Ablagerungen eines kleinen, flachen Sees charakterisiert. Änderungen im Wasserhaushalt führten letztendlich während des Präboreals zu einem Hiatus. Eine letztmalige Vernässung des Standorts führte im Atlantikum zur Entwicklung eines kalkigen Niedermoors. Die sich ergänzenden Analysen der verschiedenen und vielfältigen Organismenreste des Niedersees (z. B. Pollen, Ostracoden, Mollusken, Makroreste von Pflanzen etc.), erlaubten in sehr detaillierter Weise Änderungen im Klima und deren Auswirkungen auf das Habitat zu erfassen.researc

Bison conservation ranching on Blue Valley Ranch

Presented at the 8th international congress for wildlife and livelihoods on private and communal lands: livestock, tourism, and spirit, that was held on September 7-12, 2014 in Estes Park, Colorado.Video presenter: Perry Handyside.For 20 years, Blue Valley Ranch has been practicing conservation ranching in the Rocky Mountains of north-central Colorado with a focus on wildlife and agricultural production. An integrated resource management approach to land stewardship guides its planning process, and an adaptive management philosophy helps to make management decisions based on science and monitoring feedback. The ranch's vision of conserving wildlife habitat, building ecosystem resiliency, and producing quality livestock and forage crops is exemplified in the inclusion of the American bison (Bison bison) in its operation. As a native grazer, bison are a natural choice for raising a healthy food product on native ranges while practicing good land stewardship. Though hunted to near extinction in the late 19th century, bison have made a comeback in recent decades, due in large part to conservation-minded ranchers and private landowners. A clear understanding of their behavior and grazing ecology takes advantage of the bison's evolutionary history with the grasslands and shrublands of the western United States, and makes them a perfect fit for private lands conservation interested in supporting agriculture and healthy ecosystems

Der evolutionsgedanke in schellings naturphilosophie

[Resumen] En esta contribución se defiende la tesis de que la filosofía de la naturaleza de F. W. J. Schelling puede ser interpretada como un intento, anterior al de Darwin, de fundar filosóficamente una teoría científica de la evolución. Partiendo del problema del azar y de la finalidad en la naturaleza se muestra el desarrollo de la idea básica de evolución en Schelling desde Kant. La aproximación contenida en esa idea a una ontología procesual es de interés incluso para las discusiones actuales sobre la teoría de la evolución, aun cuando cabe considerar como superada la forma concreta de la filosofía de la naturaleza del idealista alemán.[Sommaire] Dans cette contribution est défendue la thèse dont la philosophie de la nature de F. W. J. Schelling peut être interprétée comme une tentative, antérieure à celle de Darwin, de fonder philosophiquement une théorie scientifique de l‘évolution. En partant du problème du hasard et de la finalité dans la nature on montre le développement de l‘idée basique de l’évolution chez Schelling depuis Kant. L‘approche à une ontologie processuelle contenue dans cette idée est d‘un intérêt pour les actuelles discussions sur la théorie de l‘évolution, même s‘il faut considérer comme étant dépassée la forme concrète de la philosophie de la nature de l‘idéaliste allemand.[Abstract] In this paper I try to show that the philosophy of nature of F. W. J. Schelling can be considered to be an attempt to substantiate a scientific theory of evolution before Darwin. Starting from the problem of accident and suitability in nature the basic idea of evolution in Schelling is developed going back to Kant. The examination shows that the approach of an ontology that is based on processes is contained within this idea. This may still be of interest in actual debates on the theory of evolution, even if the definite form of Schellsophy oing’s philof nature is to be regarded as outdated

A única intuição – o único pensamento: Sobre a questão do sistema em Fichte e em Schopenhauer

No artigo que se segue, iremos relacionar o tema „intuição“ e „pensamento“ao problema, virulento no idealismo alemão, da sistemática filosófica. Depois que aconcepção kantiana de sistema assente na “Arquitetônica da razão” foi criticada comoformalista e que, ao mesmo tempo, se propagou no século XVIII a crítica aos sistemasracionalistas, exercida antes pelo empirismo, irrompeu no final desse século uma crisena filosofia, expressa talvez de modo mais marcante em um “fragmento” de FriedrichSchlegel: "É igualmente mortal ao espírito ter um sistema e não ter nenhum". Fichte eSchopenhauer tratam da questão do sistema reportando-a à relação entre intuição epensamento