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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.
121

Studies toward the synthesis of photolabile HNO donors – an exploration of selectivity for HNO generation

Fejedelem, Zachary Alan 25 August 2015 (has links)
No description available.
122

An Intervention Informed by the Principles of Motivational Interviewing to Enhance Intent to Donate Blood among Prior Blood Donors

Fox, Kristen R. January 2015 (has links)
No description available.
123

Nitric oxide donors and superoxide probes: synthesis and properties

Lu, Dongning 27 August 2009 (has links)
No description available.
124

Cypriot Donor Portraiture: Constructing the Ideal Family

McNulty, Barbara R. January 2010 (has links)
This study focuses primarily on donor portraits of families found in Cypriot wall paintings and icons created during the Lusignan and Venetian periods. Although donor portraiture is a mode of expression that dates to antiquity, in the medieval period an increasingly prosperous upper middle class used this genre more frequently. My concern is with the addition of children to these portraits and the ways in which this affects the family portrayal on Cyprus. These portraits are intriguing because they provide a rare glimpse into the culture and people of this island as constructed within the medium of portraiture. They provide visual evidence of the donors' ideals of family in these lasting monuments to their memory. There are noticeable changes in these portraits through time that indicate the shifting foreign rulership faced by the population. Part of the Byzantine Empire until captured by Richard the Lionheart in 1191, Cyprus came under Frankish domain when it was transferred in 1192 to Guy de Lusignan, the dispossessed King of Jerusalem. For years Cyprus had been a stopping place for pilgrims and, later, crusaders on their way to the Holy Land. By the time Cyprus came under Venetian rule, it had grown as a stopping place for merchants as part of their trade route to the East. This exposure to cross cultural trade, migrations, and differing reigning powers makes Cyprus a complex study in social history. These layers of mixed social identities across ethnic, religious and political boundaries are documented in the island's donor portraits. Part of this analysis is an attempt to discern in these constructed identities what is indigenous, what is foreign and what is part of the changing times. A close examination of these images uncovers this mingling of identities and certain conventions in the way these donor portraits become expressions of the family. The strategy used to examine these donor portraits is to look at them by employing some of the characteristic functions of portraiture, in this case as outlined by Shearer West in her introduction to portraiture. After an introductory chapter that details some background on donor portraiture and the art of Cyprus, each of the following chapters uses two main images for comparison to explore the ways in which they might reveal aspects of the family. This comparative method is used in the successive chapters with the one constant image of the Zacharia family, painted during the Venetian occupation, as a basis for comparison. Chapter two takes this portrait and compares it to the portrait of Neophytos, a twelfth-century hermit monk who also used the Deësis scene as the setting for his portrait. By looking at these particular scenes as works of art, this chapter introduces ideas to consider throughout the dissertation on the ways these constructions reveal wishes of the donors, such as strategies of hierarchy, of veneration and viewer's access. Chapter three explores how the family group portrait serves as a document for the biography of the family. Chapter four deals with the important social practice of the dowry and my idea that some of the later portraits, which include daughters, may be displaying dowry wealth. Chapter five looks at family commemorative portraiture found particularly in icons, beginning the fourteenth century, where deceased family members are portrayed alongside, seemingly, living family members. Finally, in chapter six, I examine the ways in which these family portraits may indicate political changes on the island, especially as Cyprus moves from a feudal society to a commercial one in the Venetian period. In order to facilitate discoveries that might be made by organizing the material in a systematic manner, I have assembled a catalogue of Cypriot family donor portraits and a chart indicating the numbers of men, women and children included in family groups, in the appendices. It is my hope that this dissertation will create more discussion about family groups and will, hopefully, uncover other portraits that may be added to this list, making it a more complete picture of the surviving record. / Art History
125

Cross-Conjugation Effects on Fused β, β'–π–Extended Porphyrins

Washburn, Spenser L. 12 1900 (has links)
Cross-conjugation in molecules has been seen in nature for many years but was not pursued due to the difficulty of their synthesis and their lack of stability. Recently, it has become more interesting due to the rise of molecular electronics. Linear conjugation serves well as the wires to conduct electrons, but molecular electronics are made up of more than just wires. Molecules are needed that possess an on/off switch that can allow or deter conduction. Cross-conjugated systems show promise in their ability to be turned on or off from external stimuli. Pentacene quinone is a well-known cross-conjugated molecule that already shows promise in the field of molecular semiconductors. By synthetically fusing the pentacene quinone to the β, β' positions of a porphyrin, it has been shown that both the solubility and stability have been greatly improved. This has allowed us to pursue functionalization of the quinone moiety. Several new cross-conjugated pentacene quinone fused porphyrin systems were synthesized and studied. It was found that cross-conjugated platinum porphyrins show enhanced fluorescence, and phosphorescence that shifts toward the Near IR. Additionally, strong electron withdrawing groups show potential in charge transfer, and a lower HOMO to LUMO gap, while mildly withdrawing groups have a higher HOMO to LUMO gap. Furthermore, a new method to introduce halogenated methine bridges at the pentacene quinone core was developed, thus opening the doors to new polycyclic aromatic hydrocarbons to be synthesized and studied.
126

An Evaluation of Donor Agencies’ Policies on Participatory Development: the case of Ghana

Danquah, Joseph K., Analoui, Farhad, Koomson, Yvonne E.D. 02 February 2017 (has links)
Yes / This paper critically evaluates guidelines concerning participatory development by the World Bank and USAID. It focuses on the different conceptual frameworks adopted in order to examine the differing ways of adopting participation in their development agenda. A literature-based method was adopted and the analysis included evaluation of five documented experiences including the Ghana Secondary Education Improvement Project and Ghana Water Sanitation and Hygiene Project from both the World Bank and USAID. Baum project cycle stages have been taken as activities for project participation. The findings are; the need for better planning; ensuring sustainability; and involving beneficiaries.
127

Synthetic Routes to 3-Fold Symmetric Tridentate Oxygen Donor Ligands

Clevenger, Margo 08 August 1997 (has links)
The class of ligands represented by [CpCo(P(O)(OR)2)3]-, L- , were first synthesized by W. Kläui in 1977. These ligands have been found to coordinate to a variety of low and high oxidation state metals through the use of its three P=O oxygen atoms as donors. The ligands act as mono-anionic six electron donors which make them similar to the more widely known cyclopentadienyl ligands, (C5H5-xRx)-, but have electronic properties like those of fluoride or oxide. Also, it has been found that the coordination chemistry of L- resembles the unsubstituted tris(pryrazolyl)hydroborato six electron ligand, (RB(pz)3)-. All three of these ligands can be modified by changing the substituent R. The Kläui ligand offers a good opportunity to synthesize a chiral derivative. In the process to obtain the chiral version, (cyclopentadienyl)tris(biphenyl-phosphito-P)cobaltate(1-), 18, was synthesized from 2,2'-biphenol. This was characterized through NMR, mass spectroscopy, and XPS. Next, a racemic version, (cyclopentadienyl)tris(biphenylphosphito-P)cobaltate(1-), 17, was synthesized from (±)1,1′-bi-2-naphthol. A one-pot synthesis for the rac-binaphthyl phosphite derivative was developed with an increased yield from the previously published synthesis. The racemic version of the ligand was characterized by NMR and mass spectroscopy. The chiral version has not yet been synthesized, however, by following the developed procedure for the non-chiral version, the ligand could be synthesized from optically active 1,1'-bi-2-naphthol. / Master of Science
128

A New Approach to the Allocation of Aid Among Developing Countries: Is the USA Different from the Rest?

Harrigan, J., Wang, Chengang January 2011 (has links)
No / This paper attempts to explain the factors that determine the geographical allocation of foreign aid. Its novelty is that it develops a rigorous theoretical model and conducts the corresponding empirical investigations based on a large panel dataset. We run regressions for different major donors (United States, Canada, France, Italy, Japan, United Kingdom, and multilateral organizations). with the explicit objective of establishing whether the United States, in light of its geopolitical hegemony, behaves differently from others. We find that all the donors respond to recipient need in their allocation of aid, but that the United States puts less emphasis on this than the other donors with the exception of Japan. We also find that the United States puts more emphasis on donor¿recipient linkages than do the other donors suggesting that the United States attaches greater importance to issues of donor interest, for example, geopolitical, commercial, and other links with specific recipients.
129

The Use of a Solid Hydrocarbon as a Graphite Substitute for Astaloy CrM Sintered Steel

Pieczonka, T., Georgiev, J., Stoytchev, M., Mitchell, Stephen C., Teodosiev, D., Gyurov, S. January 2004 (has links)
Yes / Abstract Höganäs Astaloy CrM powder was used to prepare mixtures with 0.3-1.6 % carbon contents, both with and without 1 wt.% manganese additions. The carbon was added in three ways: as a graphite powder, as a solid CnHm hydrocarbon powder, and as a mixture of both. Green compacts were pressed at 300 - 800 MPa and sintered isothermally at temperatures in the range 1170 - 1295°C under flowing high purity nitrogen or nitrogen/hydrogen (9:1) atmosphere. Compressibility of the powder mixtures was investigated. Carbon loss occurring during sintering was carefully monitored. Sintering behaviour of numerous combinations of carbon content was investigated by dilatometry. For high carbon contents and high sintering temperatures, densification resulted from controlled generation of a liquid phase. Advantages of using solid hydrocarbon as a carbon donor and of Mn addition in powder metallurgy processing of steels are indicated.
130

Spectral, Electrochemical, Electron Transfer, and Photoelectrochemical Studies of Tetrapyrrole Derived Supramolecular Systems

Webre, Whitney Ann 12 1900 (has links)
Energy- and electron-transfer processes in molecular and supramolecular donor-acceptor systems are of current interest in order to develop light-energy harvesting systems through designing covalently linked donor-acceptor systems or utilizing self-assembled donor-acceptor systems. The research presented in this dissertation deals with the electrochemical, anion binding, and photochemical studies of various oxoporphyrinogen (OxPs), porphyrin, corrole, and phenothiazine systems. The first chapter provides a brief introduction to the material discussed in the subsequent chapters. The second chapter discusses the bromination of meso-tetraarylporphyrings and how that affects their electrochemical, catalytic, and other properties. Bromination of these porphyrins and oxoporphyrinogens allow the HOMO-LUMO gap to increase revealing blue-shifted absorption. Brominated OxPs and bis-crown ether OxP self-assembled with anions depending on strength of the anion and size of the binding site. The addition of crown ethers allows a cation binding site which makes a self-assembled donor-acceptor supramolecular system.Chapters 5 and 6 discuss a series of donor-acceptor conjugates based on zinc porphyrin as the electron donor and copper(III) corrole as the electron acceptor. These studies illustrate the importance of copper(III) corrole as a potent electron acceptor for the construction of energy harvesting model compounds, and constitute the first definitive proof of charge separation in ZnP-CuIIIC systems.Chapter 7 summarizes several interesting observations made in the present study on DSSCs built on two types of phenothiazine dyes having one or two cyanocinnamic acid groups.

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