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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.
51

The sinking rate and transparent exopolymer particle (TEP) production of Hemiaulus hauckii

Hoppe, Kellie Sue 08 November 2013 (has links)
Diatom-diazotroph associations contribute extensively to vertical flux in the modern ocean, and are linked to extensive sedimentary layers in the paleo-record formed either by rapidly sinking aggregates or more slowly sinking cells and chains. Although diatom sinking rates have been extensively studied, the sinking rates of these diatom symbioses are poorly documented. The effect of silicate and phosphate limitation on the sinking rate of Hemiaulus hauckii and its symbiont Richelia intracellularis were determined in semi-continuous cultures using a SETCOL. TEP (transparent exopolymer particle) was measured concurrently for linkages to aggregate formation. Although cells occurred in chains of 1-20 cells long, aggregate formation did not occur in semi-continuous cultures. There was no significant effect of P or Si limitation on sinking rates compared to controls. Although H. hauckii possess a symbiont that lacks gas vesicles, sinking rates (0.04-0.72 m/day) were within the range predicted by size-rate relationships. A portion of each H. hauckii experimental measurement ascended as well with significant differences found between the lowered P 80% exchange and the lowered Si with 80% exchange (p=0.05) and between the lowered Si with 80% exchange and the Si control batch culture (p=0.039). TEP production did not change significantly between treatments. However, a fraction of TEP in each population was positively buoyant as well, with ascent rates between 0.32-0.49 m/day. This study confirms an earlier report of positive buoyancy in TEP as well as noting that a significant fraction of the Hemiaulus symbiosis can be ascending within the population. / text
52

HPLC separation of amines with a zirconia-based column coupled to a gas- phase chemiluminescence nitrogen specific detector (CLND)

Salinas, Silvia Adriana 30 September 2004 (has links)
Gas phase chemiluminescence nitrogen specific detector (CLND)is used for the direct analysis of underivatized nitrogen-containing components such as alkylamines that can not be detected by the so called universal HPLC detector, the UV detector. However, alkali metal hydroxides can not be used as mobile phase constituents with the CLND because they form non volatile particulate combustion products that foul the detector. Therefore, trimethylsulfonium hydroxide (TMSOH) has been selected as a strong base for use with the CLND, because its combustion products, CO2, H2O and SxOy are volatile. An alkali-stable zirconia-based column was used and coupled to the CLND. Zirconia-based columns are mechanically and hydrolytically more stable than silica-based columns, which have a working pH range from 3 to 8 only. Zirconia-based columns can be used at a pH from 1 to 14 and can be used at temperatures up to 200˚C. The separation of amines was carried out at high pH values where the amino groups were deprotonated. Primary, secondary, tertiary and quaternary amines were separated using a pH=13.7 mobile phase that contained only TMSOH, methanol and water. Good peak shapes were observed for all, except n-alkylamines and samples that contained both amino groups and alcohol groups.
53

Design and use of surface modifiers as tools for understanding and controlling interfaces in organic electronics

Smith, O'neil Lohanica 22 May 2014 (has links)
This thesis focuses on the use of surface modifiers as tools for probing and/or controlling interfaces. Surface modification of transparent conducting oxides (TCOs) with organic and organometallic modifiers can be used as a tool for mediating interfacial energetics as well as probing the kinetics of charge-transfer at the metal oxide/organic interface. The synthetic tunability of these modifiers allows us to design molecules based on various parameters, which include the nature of the binding, spacer, and terminal groups. Based on this framework, several modifiers were synthesized and used to investigate surface energy tuning as well as charge injection kinetics as a function of molecular structure. More specifically, we use XPS/UPS to examine the evolution of the chemical structure and frontier orbital levels of the TCO/organic interface as a function of the chosen surface modifier. In addition, we investigate the impact that various molecular binding groups have on mediating the kinetics of charge-transfer. In the last section of this body of work we examine the development of dielectric nanocomposite films for capacitor applications. More specifically, we examine the use of phosphonic acid modifiers to functionalize barium titanate nanoparticles in order to provide miscibility with a suitable polymer host. The effect of various modifiers on the dielectric properties not nanocomposite thin films was examined.
54

A color blending model and a color correction algorithm for additive optical see-through displays

Kirshnamachari Sridharan, Srikanth 06 October 2013 (has links)
Optical see-through display (OSTD) is a transparent digital display which simultaneously gives access to the digital contents and the real world objects behind it. Additive optical see-though display is a hardware subtype of OSTD which has its own light source to create the digital contents. In Additive OSTD, light coming from background objects mixes with the light originating from the display causing what is known as the color blending problem. The work in this thesis provides a solution to the color blending problem. In order to understand the problem, this thesis first presents a new color blending model for additive OSTD based on two display induced distortions: the Render distortion and the Material distortion. A new method called Binned Profile (BP) method which accounts for the render distortion is developed to predict the blended color, when applied on the color blending model. BP method is validated with other known methods and is shown to be the most accurate in predicting the color blends with 9 just noticeable differences (JND) in worst case. Based on the BP method, a new color correction algorithm called BP color correction is created to solve the color blending problem. BP-color correction finds the alternative digital color to counter balance the blending. The correction capacity of various digital colors were analysed using the BP color correction approach. BP color correction is also compared and proven to be better than the existing solution. A quicker version of the correction called quick correction is also explored. The thesis concludes with an exploration of the material distortion, explains the limitations of BP-correction, provides design recommendations .
55

A color blending model and a color correction algorithm for additive optical see-through displays

Kirshnamachari Sridharan, Srikanth 06 October 2013 (has links)
Optical see-through display (OSTD) is a transparent digital display which simultaneously gives access to the digital contents and the real world objects behind it. Additive optical see-though display is a hardware subtype of OSTD which has its own light source to create the digital contents. In Additive OSTD, light coming from background objects mixes with the light originating from the display causing what is known as the color blending problem. The work in this thesis provides a solution to the color blending problem. In order to understand the problem, this thesis first presents a new color blending model for additive OSTD based on two display induced distortions: the Render distortion and the Material distortion. A new method called Binned Profile (BP) method which accounts for the render distortion is developed to predict the blended color, when applied on the color blending model. BP method is validated with other known methods and is shown to be the most accurate in predicting the color blends with 9 just noticeable differences (JND) in worst case. Based on the BP method, a new color correction algorithm called BP color correction is created to solve the color blending problem. BP-color correction finds the alternative digital color to counter balance the blending. The correction capacity of various digital colors were analysed using the BP color correction approach. BP color correction is also compared and proven to be better than the existing solution. A quicker version of the correction called quick correction is also explored. The thesis concludes with an exploration of the material distortion, explains the limitations of BP-correction, provides design recommendations .
56

Transparente Elektronik für Aktiv-Matrix-Displays

Görrn, Patrick January 2008 (has links)
Zugl.: Braunschweig, Techn. Univ., Diss., 2008
57

Pulsed laser deposition and thin film properties of p-type BaCuSF, BaCuSeF, BaCuTeF and n-type Zn₂In₂O₅ wide band-gap semiconductors /

Kykyneshi, Robert. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.
58

Optical low coherence reflectometry for process analysis /

Shelley, Paul H. January 1996 (has links)
Thesis (Ph. D.)--University of Washington, 1996. / Vita. Includes bibliographical references (leaves [197]-201).
59

Magnetronsputtern von hochleitfähigen ZnO:Al-Schichten für die Photovoltaik

Ruske, Florian January 2009 (has links)
Zugl.: Giessen, Univ., Diss., 2009
60

The clarification and analysis of transparency and reflection as an artistic concept

Patten, Benton Penrod. Gregor, Harold, January 1974 (has links) (PDF)
Thesis (Ed. D.)--Illinois State University, 1974. / Title from title page screen, viewed Oct. 13, 2004. Dissertation Committee: Harold Gregor (chair), Jack Hobbs, Kenneth Holder, Harold Boyd. Includes bibliographical references (leaves 139-141) and abstract. Also available in print.

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