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The effect of hydration state, Fe, and spin state of Fe on the elasticity of mantle minerals at high pressure
No full textFinally, I addressed the cause of discrepancies in current studies of the effect of water on elastic properties of wadsleyite. To rule out the systematic errors in the determination of water content measured by different methods, I measured water content of wadsleyite using the Fourier Transform Infrared method. The results show that water content of wadsleyite is nearly half of that using Secondary Ion Mass spectroscope. This difference can explain current discrepancies in the reported effects of hydrogen content on the elasticity of wadsleyite.Made available in DSpace on 2015-09-28T15:12:33Z (GMT). No. of bitstreams: 2
license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5)
3347557.pdf: 6226728 bytes, checksum: 9e3045bd09149f1ce42e5ef3116e7575 (MD5)
Previous issue date: 2008Embargo set by: Seth Robbins for item 87821
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 Only132 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2008
Controls on Heavy Metal Mobility at the Pecos Mine Operable Unit, New Mexico
No full textA process model of this drainage shows the main controls on the pH are reaction with local bedrock, limestone conglomerate, and concurrent mixing with tributary streams draining unmined regions. Models that account for both calcite dissolution and mixing of up to three kilograms background water per kilogram of mine drainage water ratio reproduce the observed decrease in aqueous metal concentrations with increasing pH. Contaminant concentrations attenuate via three different pathways: zinc, magnesium, manganese, and sulfate concentrations decrease primarily through dilution; aluminum, copper, and iron precipitate directly from solution as oxide and hydroxide phases; lead adsorbs to precipitating hydroxide surfaces.Made available in DSpace on 2015-09-28T15:12:36Z (GMT). No. of bitstreams: 2
license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5)
9944795.pdf: 2841090 bytes, checksum: a22ea04e74bda0997d0f352426e86fda (MD5)
Previous issue date: 1999Embargo set by: Seth Robbins for item 87833
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 Only114 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1999
The Direct and Indirect Effects of Insectivory by Birds in Two Neotropical Forests
No full textMost forest birds include herbivorous arthropods in their diet. Experimental tests of whether bird predation can affect arthropod abundance and plant damage are few, however, and restricted to saplings in relatively low diversity systems. In two lowland tropical forests, I tested whether birds indirectly defend canopy and understory plant foliage from arthropod herbivores. The two forest sites differed in age, tree species diversity and rainfall seasonality. Birds significantly reduced local arthropod densities in the canopy of a seasonally dry forest. Moreover, the taxonomic composition of arthropods changed in the absence of bird predation, with greater densities of chewing arthropods where foliage was inaccessible to birds. Consequentially, leaf damage increased by 86% where foliage was inaccessible to bird foraging. In contrast, effects of bird predation were not observed on understory saplings, where leaf production and turnover rates were lower. Furthermore, I observed little evidence of strong predator effects in either stratum within the more mature, wetter forest. Densities of birds were greater in the seasonally dry forest relative to the wetter site. Attack rates by birds were similar in the two forests, but capture rates were greater in the seasonally dry forest. Overall, cascading effects of bird predation were observed when and where resource availability for arthropods was greatest. These results imply that birds are an important element of some Neotropical communities via their indirect defense of canopy trees. Such conditional results, however, suggest that broad generalizations about the outcome of multitrophic interactions are inappropriate for tropical forests, where environmental heterogeneity is great.Made available in DSpace on 2015-09-28T15:22:05Z (GMT). No. of bitstreams: 2
license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5)
3086206.pdf: 4925273 bytes, checksum: a502deb95095cac3f62efe8ef5132348 (MD5)
Previous issue date: 2003Embargo set by: Seth Robbins for item 88292
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 Only115 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2003
Metalorganic chemical vapor deposition, ion beam mixing, and selective epitaxy of III-V semiconductors
No full textMetalorganic Chemical Vapor Deposition (MOCVD) is a versatile growth technique commonly used to grow III-V compound semiconductor materials. A review of many seminal studies investigating the growth mechanisms of GaAs epitaxial growth is presented. Carbon is an intrinsic impurity in GaAs and AlGaAs grown by MOCVD and a number of growth variables can be modified to minimize impurity levels. Results will be presented illustrating a new dependence of background carbon levels on growth temperature in AlGaAs. These data are discussed qualitatively in terms of existing models for GaAs growth and carbon incorporation.Ion beam mixing in III-V semiconductor matrices has also been investigated. It is observed that mixing in semiconductor materials is much greater than metal systems. In addition, the amount of mixing is dependent upon the crystal structure of the matrix, decreasing sharply at an irradiation temperature where the matrix remains crystalline during the irradiation.Selective epitaxy of GaAs and InGaAs has been investigated using MOCVD. Several aspects of the growth process are discussed and results are presented for the successful operation of semiconductor lasers fabricated by a three-step growth technique utilizing selective area epitaxy to achieve lateral band-gap tailoring.Made available in DSpace on 2011-05-07T13:48:40Z (GMT). No. of bitstreams: 2
license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5)
9543587.pdf: 3178849 bytes, checksum: f901f4ead6a60930ea4bf04630e2a40c (MD5)
Previous issue date: 1995Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding ([email protected]) on 2011-05-07T14:59:26Z
Item is restricted indefinitely.Restriction data tranferred 2014-07-01T11:28:02-05:00
Original Data
Group with Access UIUC Users [automated]
Release Date: none
Reason: ETDs are only available to UIUC Users without author permissionETDs are only available to UIUC Users without author permissionU of I Onl
Molecular genetic characterization of essential conjugal transfer determinants on the nopaline-type Ti plasmid from Agrobacterium tumefaciens strain C58
No full textTi plasmids of Agrobacterium tumefaciens encode a conjugal transfer system. I characterized a region, called tra, that is necessary for transfer of the nopaline-type Ti plasmid, pTiC58. tra contains the origin of conjugal transfer (oriT) and a cluster of genes the products of which are predicted to function as DNA processing and transfer components. The oriT is contained within a 260-bp intergenic region flanked by transfer genes. Analysis of Tn3HoHo1-generated mutations that abolish transfer of the Ti plasmid defined an essential region of approximately six kilobases surrounding the oriT site. Expression from lacZ fusions in the tra region indicated that there is divergent transcriptional activity on both sides of the oriT site. I determined the nucleotide sequence of 8755-bp that spans this region on pTiC58. Eight ORFs, traA-D, traF, traG, and orfX, were predicted from the sequence. Directed expression of gene products from traA, traC, traD, and traG in E. coli, confirmed that these ORFs encode proteins of the predicted sizes. Deduced amino acid sequences from tra genes showed that proteins encoded by tra are similar to other transfer proteins. I also examined the regulation of gene expression within the tra locus and found that in addition to the transcriptional activator, TraR and its coinducer, the N-acyl homoserine lactone molecule, AAI, control of gene activation in tra requires two other determinants. One regulatory determinant is the cis-acting promoter sequence, called the tra box, found in the intergenic region. This DNA sequence is required for expression of the divergent tra operons that is mediated by TraR and AAI. The second regulatory determinant is the product of the traM gene which modulates activation of tra genes mediated by TraR and AAI. Studies on activation of expression of tra genes led to the localization of the gene, traI, which is responsible for production of AAI in Agrobacterium. Finally, I used the information gathered from the characterization of the tra locus and its regulation to reconstitute the transfer regions from pTiC58 on two independently replicating plasmids as a binary conjugal transfer system.Made available in DSpace on 2011-05-07T13:03:09Z (GMT). No. of bitstreams: 2
license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5)
9625125.pdf: 11925886 bytes, checksum: 09b5016206d48f891713d2768d545ea3 (MD5)
Previous issue date: 1996Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding ([email protected]) on 2011-05-07T14:49:32Z
Item is restricted indefinitely.Restriction data tranferred 2014-07-01T11:22:32-05:00
Original Data
Group with Access UIUC Users [automated]
Release Date: none
Reason: ETDs are only available to UIUC Users without author permissionETDs are only available to UIUC Users without author permissionU of I Onl
Nanosoldering Single-Walled Carbon Nanotubes by Using Hafnium Diboride
No full textBecause of their extraordinary electrical and mechanical properties, single-walled carbon nanotubes (SWNTs) have been considered not only as replacements for current silicon-based microelectronics, but as building blocks for a variety of electrical devices. Indeed, most major universities and industrial laboratories, such as IBM, now have at least one group studying these materials for a variety of electronic applications. While for the individual semiconducting tube, the resistance of the off state can be more than a million times greater than that of the on state, the on-off ratio of a real-world SWNT thin film transistor (TFT) is only hundreds to several thousands depending on the device, and its mobility is much lower than expected. The core of a CNT-TFT is the thin SWNT network film, which is flexible and transparent. One reason for SWNT TFTs' low on-off ratio and mobility is the high resistance of crossed nanotube junctions in the SWNT network films. To increase the conductivity of the SWNT networks without losing optical transparency, we deposit HfB2, an electrically conductive and ultra-hard metallic ceramic compatible with carbon nanotubes. In this work, we attempt to deposit HfB2 selectively to the tube junctions. This process enhances the electrical conductivity and is expected to enhance on-off ratio and mobility when applied to CNT-TFTs.not peer reviewedSubmitted by Janice Progen ([email protected]) on 2014-01-22T16:21:53Z
No. of bitstreams: 1
ECE499-Sp2010-zhou.pdf: 884924 bytes, checksum: 9b2304d14c9fa7398afe7282089541f3 (MD5)Approved for entry into archive by James Hutchinson([email protected]) on 2014-01-22T17:05:58Z (GMT) No. of bitstreams: 1
ECE499-Sp2010-zhou.pdf: 884924 bytes, checksum: 9b2304d14c9fa7398afe7282089541f3 (MD5)Made available in DSpace on 2014-01-22T17:05:58Z (GMT). No. of bitstreams: 1
ECE499-Sp2010-zhou.pdf: 884924 bytes, checksum: 9b2304d14c9fa7398afe7282089541f3 (MD5)
Previous issue date: 2010-05Restriction data tranferred 2014-07-01T11:34:24-05:00
Original Data
Group with Access UIUC Users [automated]
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Reason: Undergraduate senior thesis not recommended for open accessItem marked as restricted to the 'UIUC Users [automated]' Group (id=2) by James Hutchinson ([email protected]) on 2014-01-22T17:05:58Z
Item is restricted indefinitely.Undergraduate senior thesis not recommended for open accessunpublishedU of I Onl
Adiabatic Fast Passage Relaxation Studies in Liquids
No full textMade available in DSpace on 2014-12-10T23:01:19Z (GMT). No. of bitstreams: 1
7212327.pdf: 4371613 bytes, checksum: 5a8e17dd97f1b5820dc525c2bbe1c53c (MD5)
Previous issue date: 1971Embargo set by: Seth Robbins for item 64092
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 Only142 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1971
Organizational Climate as a Moderator Variable in the Job Satisfaction/job Performance Relationship
No full textMade available in DSpace on 2014-12-10T23:08:59Z (GMT). No. of bitstreams: 1
7405641.pdf: 6469592 bytes, checksum: 24f7773907ff734e95476df2a1e93210 (MD5)
Previous issue date: 1973Embargo set by: Seth Robbins for item 64276
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 Only171 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1973
Geology and Geochemistry of the Sheep Rock Mineralized Norite, Albany County, Wyoming
No full textMade available in DSpace on 2014-12-11T18:10:05Z (GMT). No. of bitstreams: 1
7405700.pdf: 4724512 bytes, checksum: 8639601df2ead7f3e22cf3c36b7bbe1e (MD5)
Previous issue date: 1973Embargo set by: Seth Robbins for item 64909
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 Only151 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1973
Transient Speed Response of Two-Phase Servo Motors in Suppressed-Carrier Systems
No full textMade available in DSpace on 2014-12-04T21:02:48Z (GMT). No. of bitstreams: 1
0013499.pdf: 3392123 bytes, checksum: bb0c745bce2549f483b006f627622329 (MD5)
Previous issue date: 1955Embargo set by: Seth Robbins for item 57126
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 Only86 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1955