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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.
351

Balthasar Hubmaier's Sword: A Circumstantial Development

Wiens, Rudolph Henry January 2010 (has links)
The sixteenth century Bavarian Anabaptist, Balthasar Hubmaier (ca. 1480-1528), has had a disputed role in Anabaptist historiography ever since his martyrdom in March, 1528. On the one hand he is known as the most erudite and prolific writer of the early Anabaptists, and on the other he has been separated from the original Zurich Brethren by his rejection of two major principles, total separation from the world and absolute non-resistance, that were supposedly held unanimously by the Zurich Brethren. Today Hubmaier’s reputation for militancy has been endorsed by most writers, but this militancy is not expressed in any of his writings except On the Sword, the last tract written before his death. Using the well-documented biography of Hubmaier by Bergsten and his own writings collected and translated by Pipkin and Yoder, the thesis explores the question of the extent to which Hubmaier was willing to advocate the use of lethal force by government or against government. It is found that only one source, Johann Faber, accused Hubmaier of inciting peasant revolt , and that witness would seem dubious by any modern standard. Arguments that Hubmaier was ostracized by the Zurich Brethren are found to be conjectural and dependent upon anachronism. Thus in the critical years 1524-26, Hubmaier was a veritable Swiss Brethren. On the Sword indicates a major change in Hubmaier’s thinking, and the reasons for that change are explored.
352

Euskadi Ta Askatasuna : - Reasons for Existence. A Case Study in the Basque Country

Avazpour, Kimia Raha January 2009 (has links)
In this case study I explore why the conflict of the Basque country which involves Euskadi Ta Askatasuna (ETA) persists. The purpose is to gain an understanding of the existence of ETA. Working somewhat  as an ethnographer the method has been to observe Basque society and through semi- structured interviews gain an understanding of ETAs existence. As exemplified with the hermeneutic circle, this case study starts out with a preunderstanding of the reasons for the existence of ETA, a preunderstanding which alters many times during my visit to the Basque country. Keys to understanding the continued existence of ETA is that historical “injustices” are perceived to still exist in the Basque country. Perceptions which question the legitimacy of the Spanish state in the Basque country. Further the social base of ETA, as exemplified in election support for Herri Batasuna (HB), still remains rather strong despite the party‟s illegalization and finally, the perceived lack of a functioning democracy in Spain and the lack of legitimacy of the Spanish state in the Basque country are among the reasons for the continued existence of ETA.
353

Synthesis, characterization, anion complexation and electrochemistry of cationic Lewis acids

Chiu, Ching-Wen 15 May 2009 (has links)
Owing to the favored Coulombic attraction between the ammonium group and anion which stabilizes the B-F/B-CN bond against heterolysis, cationic borane [25]+ has great affinity toward anions than its neutral analog, and is capable of capturing fluoride or cyanide from water under bi-phasic conditions. By placing the fluorophilic silyl group adjacent to an electrophilic carbocation, a novel fluoride sensor [45]+ was obtained. Sensing occurs via a fluoride induced methyl migration from the silicon to adjacent electrophilic methylium center which is unprecedented. As a result of its strong fluoride affinity, [45]+ is able to react with KF in aqueous media at pH 7.0. The electrochemistry study of these cationic Lewis boranes reveals that the cationic character of these boranes serves to decrease their reduction potential and increase the stability of the resulting radicals. In this part of the research, we have prepared a cationic borane [27]+, which features two reversible reduction waves at -0.86 and -1.56 (vs. Fc/Fc+) corresponding to the formation of stable neutral and anionic derivatives. The one-electron reduction of [27]+ leads to the formation of a boron containing neutral radical featuring an unusual boron-carbon one-electron π bond. Further reduction of 27• results in the formation of the borataalkene derivative [27]-, which features a formal B=C double bond. The structural changes accompanying the stepwise population of the B-C π-bond are also determined, and this sequential population of B-C π-bonding orbital is also supported by theoretical computations. In order to understand the impact of the cationic nature of these boranes on their oxidative power, three novel cationic boranes ([34]+, [35]2+, and [36]3+) have been synthesized and their oxidative power were examined via cyclic voltammetry. The CV data of these compounds shows that the reduction potential of these triarylboranes is linearly proportional to the number of the pendant cationic substituents. Substitution of a mesityl group by an ArN+ group leads to an increase of the reduction potential by 260 mV.
354

Nighttime Measurements of Dinitrogen Pentoxide and the Nitrate Radical via Cavity Ring-Down Spectroscopy

Perkins, Katie C. 2009 August 1900 (has links)
Development of effective pollution control strategies for urban areas requires accurate predictive models. The ability of models to correctly characterize the atmospheric chemistry, meteorology, and deposition rely on accurate data measurements, both as input and verification of output. Therefore, the measurement techniques must be sensitive, accurate, and capable of resolving the spatial and temporal variations of key chemical species. The application of a sensitive in situ optical absorption technique, known as cavity ring-down spectroscopy, will be introduced for simultaneously measuring the nitrate radical and dinitrogen pentoxide. The cavity ring-down spectrometer was initially designed and constructed based on the experiments by Steven Brown and Akkihebal Ravishankara at the National Oceanic and Atmospheric Administration. The instrument design has since undergone many revisions before attaining the current instrumentation system. Laboratory observations provide verification of accurate N2O5 and NO3 detection with measurements of the nitrate radical absorption spectrum centered at 662 nm, effective chemical zeroing with nitric oxide, and efficient thermal decomposition of N2O5. Field observations at a local park provided further confirmation of the instruments capability in measuring N2O5 and NO3. However, detection limits were too high to detect ambient NO3. Effective and frequent zeroing can easily improve upon the sensitivity of the instrument. Determination of the source of the polluted air masses detected during these studies was unknown since the typical southerly winds from Houston were not observed. Since deployment in the field, instrumentation modifications and laboratory measurements are underway for preparation of the SOOT campaign in Houston, Texas starting April 15, 2009. Current modifications include automation of the titration with a solenoid valve and an automated filter changer. Wall losses and filter transmission for NO3 and N2O5 will be determined through laboratory measurements in coincidence with and ion-drift chemical ionization mass spectrometer prior to the SOOT project. Potential modifications to improve upon the instrument are suggested for future endeavors.
355

Inhibition of endotoxin-induced plasma leakage and edema in rat trachea and esophagus by urethan anesthesia and dimethylthiourea

Kuo, Shan-tsu 06 June 2006 (has links)
Endotoxin (lipopolysaccharide, LPS) a chemical component of cell wall of gram-negative bacteria, is an important mediator in pathogenesis of sepsis and acute respiratory distress syndrome. It causes production and release of a wide array of mediators including cytokines, chemokines, oxygen free radicals and nitric oxide from neutrophils, macrophages, endothelial cells and epithelial cells through the NF-£eB pathway. LPS increases the permeability of microcirculation, and causes the acute formation of numerous endothelial gaps among venular endothelial cells, resulting in extensive plasma leakage in the inflammatory tissue. Urethan is commonly used as an animal anesthetic for nonrecovery laboratory surgery. It is aslo an £\2-adrenoreceptor antagonist, which can suppress the activation of the cardiovascular system and reduce the angiotensin which increases the blood pressure. Urethan or its metabolites protect animals against LPS, in part, by reducing TNF-£\ release. The aims of the present study to investigate the time-course of vascular permeability in microcirculation of rat trachea, bronchus and esophagus after intravenous application of a high dose of LPS (15 mg/kg), and to reveal the role of urethan (1 g/¢V) and dimethylthiourea (DMTU, 0.375 g/¢V) in inhibition of LPS-induced plasma leakage and edema. India ink was used as a tracer dye to mark leaky microvessels after LPS application. Endothelial gaps were made visible for light microscopy by staining the borders of endothelial cells with silver nitrate. Tracheal sections were stained with toluidine blue to show the subendothelial edema formation. A high dose of LPS was administered intravenously to induce serious plasma leakage and edema and a large number of endothelial gaps formed in postcapillary and collecting venules in the rat trachea and esophagus. The peak values of plasma leakage and edema occurred 5 min after LPS (P<0.01). Urethan anesthesia significantly inhibited LPS-induced plasma leakage by 95 ¡Ó 1.7% in various parts of the respiratory tracts and inhibited edema ratio in the trachea by 57%. Urethan was also found to reduce leukocyte infiltration and the number of endothelial gaps by 46.8 ¡Ó 4.6%. DMTU pretreatment significantly inhibited plasma leakage by 88.5 ¡Ó 2.5% in the respiratory tract and inhibited edema ratio in the trachea by 89% at 5 min after LPS. It is concluded that LPS-induced increase in plasma leakage and edema correlated with the formation of endothelial gaps, and association with activation of alpha 2-adrenergic receptors and hydroxyl free radical production.
356

Part I¡GApplication of Electroorganic Chemistry toward the Synthesis of Tropane Alkaloids Part II¡GSyntheses of Aporphine Alkaloids via Radical Cyclization Reactions

Chou, Wu-Sen 07 July 2000 (has links)
Part I: Pyrrolidine derivatives were attached a methoxy group on a-C position of pyrrolidine-ring via anodic oxidation. Followed with alkylation and series of transformation under Lewis acids to obtain tropane alkaloids. Part II: Application of intramolecular radical cyclization toward the synthesis of aporphine alkaloids. Tributyltinhydride and AIBN were used to generate aryl radicals. Trapping of aryl radicals with unsaturated alkenes led to products.
357

On the importance of radical formation in ozone bleaching

Ragnar, Martin January 2000 (has links)
No description available.
358

The oxidation of glucose in aqueous solution by oxygen

Olson, Richard E., January 1967 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1967. / Includes bibliographical references (leaves 83-87).
359

Development of a computational framework for quantitative vibronic coupling and its application to the NO₃ radical

Simmons, Christopher Scott 06 July 2012 (has links)
The Born-Oppenheimer approximation is a mainstay in molecular physics and chemistry and can be considered a two step process. The first step is to solve the electronic problem with nuclei fixed in space while the second step is to then determine the nuclear dynamics on a given electronic potential energy surface. This first-step calculation of the wavefunction and electronic energies for fixed nuclei has been at the center of modern quantum chemistry for decades. While the majority of chemical processes can be investigated by considering these single electronic surface dynamics, there exist problems in which the dynamics are not constrained to a single electronic surface. One such problem that justifies going beyond the typical adiabatic approximation is the determination of energy levels in systems with strongly coupled electronic states. While some work has been done using diabatic or quasidiabatic Hamiltonians to describe such systems, the work has historically been of qualitative accuracy. Model Hamiltonians have been constructed using experimental data to help calibrate the model parameters aided by the use of lower level adiabatic calculations to help inform the model. It is only within the last few years that theorists have been able to attempt parameterization of such models using only ab initio methods. The goal of this work is to develop a computational framework for the parameterization of quantitatively accurate quasidiabatic Hamiltonians based purely on ab initio information and apply it to a notoriously difficult problem that has plagued the theoretical community for decades -- high accuracy treatment of the energy levels of the NO₃ radical. In this dissertation, high-level ab initio calculations that employ the equation-of-motion coupled-cluster method in the single, doubles and triples (EOMIP-CCSDT) have been used in conjunction with a quasidiabatic ab initio approximation to construct a vibronic Hamiltonian for the strongly coupled X²A'₂ and B²E' states of the NO₃ radical. A quartic vibronic coupling model potential of the form advocated by Köppel et al. has been used to determine the energy levels of this system to quantitative accuracy when compared to experimental data. In order to obtain sufficiently accurate potential energy surfaces necessary to parameterize a quantitatively accurate model Hamiltonian, thousands of large calculations had to be run that do not fit in memory on even the largest HPC systems. The resulting large, out-of-core solves do not map to traditional systems in a way to enable any reasonable parallelization. As a result, a new MPI-based utility has been developed to support out-of-core methods on distributed memory systems. This and other advances in scientific computing form the basis of the developed computational framework. / text
360

The Sweden Democrats : An analysis of the ideology of a radical right-wing populist party over time

Johansson, Martin, Zarpan, Hooda January 2015 (has links)
This thesis analyses the ideology of the Radical right-wing Populist Party, Sweden Democrats. The aim of the study is to see if and how the ideology of the Sweden Democrats has changed through its years of activity, by comparing the party in three periods. The focus in the analysis is put on the party's view on the Swedish national identity and on multiculturalism. The reason for analyzing the party's view on these two concepts is due to the fact that they can be seen as corner stones in a racist ideology. An explanation of the concepts will be presented in the theory chapter, which is later used in the analysis of the party. The study shows that the ideology of the Sweden Democrats has changed very little throughout its years of activity in terms of their view on the national identity and the multicultural idea. This as a result has led to a similar amount of change in the arguments that can be seen as racist, by the party.

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