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High Pressure Nuclear Magnetic Resonance Studies of Homogeneous Catalysts
No full textThe design and testing of a nuclear magnetic resonance probe for studying homogeneous catalysts from -40\sp\circC to 100\sp\circC and pressures up to 4000 psi is described. Its significant features are a built-in stirring mechanism to mix the sample under study with reactive gases, and resolution and sensitivity comparable to that obtained in ambient-pressure probes without sample spinning. Well-known organometallic reactions are used to demonstrate the probe's capabilities.A rhodium catalyst for converting syngas to oxygenated organic compounds is examined in two solvent systems, sulfolane/4-methylmorpholine and 1-methyl-2-pyrrolidinone, leading to identification of rhodium carbonyl anionic clusters present at ambient and extreme conditions. Clusters fragmented much more easily in the former solvent, leading to a smaller distribution of clusters and more pronounced changes in the clusters present with temperature and pressure changes. Hydrido carbonyl anions, expected to be catalytically important as the source of activated hydrogen, were completely absent except for a trace of H\sb2Rh\sb (CO)\sb{24}\sp{3-}.Proton relaxation and site exchange processes in the metal clusters (-H)\sb3M\sb3(CO)\sb9(\mu\sb3-CH)(M = Os,Ru) and (-H)\sb2Os\sb3(CO)\sb (\mu-CH\sb2)/(\mu-H)Os\sb3(CO)\sb (\mu-CH\sb3) are also studied. From relaxation rates, nuclear Overhauser enhancements, and spin saturation transfer, the exchange rates, activation parameters, and interproton distances are calculated for these clusters; the latter are compared with neutron diffraction measurements in the first two compounds. For the methyl compound, whose structure has not been solved by diffraction methods, the NMR data support a structure very similar to that of the methylene.Made available in DSpace on 2014-12-15T23:19:09Z (GMT). No. of bitstreams: 1
8803226.pdf: 3335575 bytes, checksum: a7db251eb5b7a0a3d9f466ddc24bb278 (MD5)
Previous issue date: 1987Embargo set by: Seth Robbins for item 70562
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Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only94 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1987
Electronic light scattering in the layered cuprates
No full textLight scattering studies of copper oxide superconductors and the parent insulator materials were performed. Dynamics of the copper oxygen planes were probed with plane-polarized photons, whereas plane-plane coupling was probed with the photons polarized perpendicular to the layers. In both cases the analysis and proposed
phenomenological models involved an xamination of the inelastic ackground continuum. The room temperature investigations of the dynamics of the copper
oxygen planes revealed strong anisotropy of the electronic scattering and established copper oxygen planes and chains as origins of an intense frequency independent continuum, which dominates light scattering spectra of copper oxide superconductors. Systematic comparison of the Raman intensities at different doping levels established stringent constraints on the theoretical models of the continuum. A detailed study of the temperature dependence of electronic scattering at different doping levels, exposed its highly unconventional properties m the normal as well as m the
superconducting state. Examination of the coupling between the copper oxygen layers with c-axis-polarized photons revealed a resonance enhanced electronic Raman continuum in YBa2Cu307. Its lineshape is consistent with weak inerlayer coupling which rapidly disappears as the oxygen content is reduced. Microscopic origin of the resonance is discussed in detail.Submitted by Carolyn Rauber ([email protected]) on 2012-01-24T20:37:37Z
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1993_reznik.pdf: 3431343 bytes, checksum: f11a2e46e33d992e6562f308d69df6dd (MD5)Made available in DSpace on 2012-01-24T20:37:37Z (GMT). No. of bitstreams: 1
1993_reznik.pdf: 3431343 bytes, checksum: f11a2e46e33d992e6562f308d69df6dd (MD5)
Previous issue date: 1993Restriction data tranferred 2014-07-01T11:09:59-05:00
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Group with Access UIUC Users [automated]
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Reason: dissertationItem marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Carolyn Rauber ([email protected]) on 2012-01-24T20:37:38Z
Item is restricted indefinitely.dissertationU of I Onl
John Dewey on Theory of Learning and Inquiry: The Scientific Method and Subject Matter
No full textThe dissertation concludes by showing that, educationally, Dewey's ideas of the scientific method have different meanings in different context. It analyzes the scientific method as empirical method, critical thinking, cooperative learning, and creative thinking, and shows the place of subject matter in each of them.Made available in DSpace on 2015-09-25T19:54:36Z (GMT). No. of bitstreams: 2
license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5)
3242815.pdf: 4587972 bytes, checksum: dfe7df45a3d9678bb922e45e707edb2e (MD5)
Previous issue date: 2006Embargo set by: Seth Robbins for item 81214
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Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only195 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006
'Truth Is Stranger Than Fiction': Black Women in American Literature of the *South
No full text"Although the South has been an enduring site of criticism in American Studies and in American literary history, my dissertation argues that it is impossible to consider what the ""South"" and what ""southernness"" mean as cultural references without looking at how black women have contributed to and contested any unified definition of that region. I focus on the late nineteenth century, a period of intense regional conflict when southern blacks witnessed the reassertion of white hegemony. Hence, the idea of the South and southern identity become synonymous with ""whiteness"" as it solidifies in literary and political narratives. The scope of my dissertation examines the relationship between Southern literature and the South's social history. Specifically, I look at that relationship by focusing on black women, fictional and historical, arguing that they are unacknowledged agents of cultural change. Though black women were integral to southern society, they are often invisible in historical accounts of regional politics and culture, especially as southern black women. Black women, likewise, are a largely under-critiqued presence in the regional fiction of the period. My dissertation reconsiders the South and explains how black women contributed to its literary and cultural history."Made available in DSpace on 2015-09-25T20:15:13Z (GMT). No. of bitstreams: 2
license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5)
3182291.pdf: 9618024 bytes, checksum: 37a6ae77cd58c66036f4ca8c5d2d4a1d (MD5)
Previous issue date: 2005Embargo set by: Seth Robbins for item 82692
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Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only175 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2005
Exploiting System Diversity in Peer-to-Peer Publish -Subscribe Systems
No full textFourthly, the systems described in this thesis have been comprehensively evaluated via both PlanetLab deployment and simulation. Our deployments used up to 400 PlanetLab servers world-wide. Our largest simulations model 10, 000 nodes. Our experimental methodology is constructed using an extensive amount of real-world traces. For instance, to evaluate Rappel using realistic user subscriptions, we gathered the subscription profiles of 1.8 million LiveJournal users over six months. The evaluation presented in this thesis also makes use of the following previously collected traces: Internet topology, end-to-end latency fluctuations between PlanetLab nodes, bandwidth availability between PlanetLab nodes, and end user churn observed in peer-to-peer file sharing applications.Made available in DSpace on 2015-09-25T20:20:42Z (GMT). No. of bitstreams: 2
license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5)
3363052.pdf: 1854644 bytes, checksum: fc719ccbdb41af83b093a77e0d75d5e8 (MD5)
Previous issue date: 2009Embargo set by: Seth Robbins for item 83135
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only111 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2009
Chicana /O Murals of California: Indigenist Aesthetics and the Politics of Space, 1970--2000
No full textBy depicting images of indigenous culture and history from the Americas, these artists embraced an aesthetic that rewrote their place in U.S. history and society. Indigenism, as an ideology and aesthetic, emerged during the early decades of the twentieth century in various parts of Latin America, but Mexico in particular. Unlike in Mexico, however, for Chicanas/os, Indigenism was not an institution supported and endorsed officially, but rather a discourse occurring at the margins of U.S. dominant culture. Chicanana/o murals, for the most part, did not grace the walls of major public and government buildings; rather, they decorated the walls along the streets of the barrios and urban neighborhoods through out the country.Made available in DSpace on 2015-09-28T15:52:57Z (GMT). No. of bitstreams: 2
license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5)
3086109.pdf: 11817781 bytes, checksum: 8f1356e8271905158858fbbc85770589 (MD5)
Previous issue date: 2003Embargo set by: Seth Robbins for item 88649
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Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only287 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2003
Rewetting Temperature During Top and Bottom Reflood
No full textMade available in DSpace on 2017-07-06T18:56:22Z (GMT). No. of bitstreams: 2
Siegel_Alan_D_MS.pdf: 51485799 bytes, checksum: f0352a352d8b1c48211ca671f4c53089 (MD5)
license.txt: 4813 bytes, checksum: 715c4321821a960fa1a1e91d2ac7ebce (MD5)
Previous issue date: 1979Embargo set by: Seth Robbins for item 99682
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Reason: Restricted to UIUC communityRestricted to UIUC communityU of I Onl
Development and Evaluation of a Modified VFR Lighted Flyway Marker
No full textIn air-to-ground visual search, size and color are the most important factors during daytime observations. Several testing schemes were developed to evaluate the effects of colors, color combinations, marking patterns, and size on the perceptibility of an object. Based upon these results, a commercially available structure manufactured by Sprung Instant Structure was obtained and modified to serve as a prototype marker. Flight evaluations of the prototype marker were conducted at the University of Illinois ATREL facility and Schaumburg Regional Airport. Based upon the results obtained in this study, the recommended size for the marker was a fourteen-panel structure with a 60-foot diameter and 26 feet in height. The colors and marking that were most conspicuous were tangerine orange and yellow, in an alternating, solid-colored pattern. For nighttime detection, computer simulation was utilized to determine the most conspicuous flashing pattern for a MVLFM beacon. According to the computer test results, the flashing characteristics of the Morse code letter 'S' resulted in the quickest detection, as confirmed by flight observations. Based upon findings in the literature and flight observations, the MVLFM beacon should be green in color. The results of this study indicate that the prototype could be implemented as a visual marker along the VFR flyway in the Chicago area. Further investigations will be necessary to fully understand the capability of the MVLFM as well as its impact on aviation around the Chicago area.Made available in DSpace on 2015-09-25T21:05:18Z (GMT). No. of bitstreams: 2
license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5)
9971098.pdf: 17346308 bytes, checksum: a19d2a909bf5d1341e67bc941906b3ca (MD5)
Previous issue date: 2000Embargo set by: Seth Robbins for item 84785
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Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only362 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2000
Molecular and Biochemical Analyses of a Three-Subunit Euryarchaeal Clamp Loader Complex
No full textDNA polymerase requires two processing factors, sliding clamp and clamp loader, to direct rapid and accurate DNA replication. In eukaryotes, the ring-shaped sliding clamp, proliferating cell nuclear antigen (PCNA), encircles double-stranded DNA within its central hole and tethers the DNA polymerases onto DNA. A spiral-shaped pentameric protein, replication factor C (RFC), functions as the clamp loader, which installs the sliding clamp onto primer-template junction of DNA in an ATP-dependent manner. The critical clamp loader acts as molecular switch from distributive to processive DNA synthesis. Here, we describe a novel form of clamp loader from the euryarchaeon Methanosarcina acetivorans (Mac). The M. acetivorans clamp loader comprises two similar small subunits (MacRFCS1 and MacRFCS2) and one large subunit (MacRFCL). Since the simplest RFC is made up of two different subunits and the most complex form is made up of five different subunits, the MacRFC may represent a critical link in the evolution of complex clamp loaders from simple forms in the archaeal/eukaryotic sister lineage. MacRFCS1 was found to form oligomers in solution but not MacRFCS2. The clamp loader complex stimulated PCNA-dependent DNA elongation by a cognate DNA polymerase. The site-directed mutagenesis in the Walker A and SRC motifs indicated that both motifs in MacRFCS1 are essential for clamp loading. A densitometric method suggested that the spatial distribution of MacRFC complex is similar to that of the E. coli clamp loader which has the same 3:1:1 ratio and is made of three gamma subunits (motor), a delta' subunit (stator) and a delta subunit (wrench). Furthermore, our studies on this archaeal three-subunits clamp loader have provided important biochemical, molecular, and evolutionary insights into the function of RFC, an indispensable molecular switch in archaeal/eukaryotic DNA replication.Made available in DSpace on 2015-09-25T21:08:26Z (GMT). No. of bitstreams: 2
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3337731.pdf: 2425515 bytes, checksum: bc6017b480c9e3bffeaa460c01175475 (MD5)
Previous issue date: 2008Embargo set by: Seth Robbins for item 84894
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Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only125 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2008
Households and Hegemony: An Analysis of Historic Creek Culture Change
No full textCulture change in the post-contact Southeast is often defined through the analysis of large socio-political movements and unique historical events, without an appreciation for the role of smaller social groups and individual social actors. This dissertation assesses Creek culture change through the analysis of Atasi Phase (A.D. 1600-1715) and Tallapoosa Phase (A.D. 1715-1836) households in central Alabama. Research reveals alterations in the material, social, and behavioral composition of Creek households, as well as changes in the nature of Creek social relationships. Increases in the size and number of household food storage facilities, greater access to Euroamerican trade goods, a decrease in domestic structure size, and changes in settlement structure are shown to represent the desire of individual households to garner increased social and economic independence for themselves at the expense of existing cultural institutions. Such changes represented significant challenges to the power of social elites and the principle of hereditary social inequality, threatening the basis of traditional chiefly authority. Escalating reliance upon strategies designed to advance the economic status of households is shown to be a powerful explanatory model for the cultural changes experienced by the historic Creek. Ultimately, historic Creek culture change is demonstrated to be have been shaped by the choices made by individuals and small-scale social units rather than merely the result of larger social and political events.Made available in DSpace on 2015-09-25T22:41:03Z (GMT). No. of bitstreams: 2
license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5)
9737286.pdf: 10809885 bytes, checksum: 647f707b1507c392948536f6595b3c16 (MD5)
Previous issue date: 1997Embargo set by: Seth Robbins for item 86588
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only224 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1997