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A comparison of the white and the colored schools of Texas

Description: The purpose of this study is to determine the status of the educational opportunities of the white and the colored child in the State of Texas during the year of 1935-36 and to locate the inequalities with reference to: building equipment, transportation, library facilities, teachers, average daily attendance of pupils, teacher-pupil ratio, per pupil cost of instruction, age-grade distribution, and age of pupils when graduated.
Date: August 1938
Creator: Kattner, Bruno A.
Partner: UNT Libraries

A Place to Call Home: A Study of the Self-Segregated Community of Tatums, Oklahoma, 1894-1970

Description: This study examines Tatums, Oklahoma, under the assumption that the historically black towns (HBT) developed as a response to conditions in the South. This community provides a rich example of the apparent anomalies that the environment of self-segregation created. Despite the widespread violence of the Klan, the residents of the HBTs were not the targets of lynching or mob violence. During the years after World War II, Tatums residents enjoyed the greatest prosperity. The final chapter looks at the battle Tatums' residents fought to keep their school from being closed after the state of Oklahoma began to enforce the Brown v. Board of Education decisions in the 1960s. Their solidarity during the desegregation transition remained powerful enough for them to negotiate compromises regarding the fair treatment of their children in a world that was integrating around them.
Date: August 2005
Creator: Ragsdale, Rhonda M.
Partner: UNT Libraries

Racial Segregation in Dallas Public Housing: 1970-1976

Description: Racial residential segregation in Dallas public housing projects is analyzed before and after the implementation of the "central tenant assignment plan," adopted in May of 1975, Among the socioeconomically segregated population served by public housing, the effects of race and the nondiscrimination policy are investigated using project occupancy data. Indexes of dissimilarity are used to measure racial segregation, and the racial compositions of the communities in which the projects are located are described using 1970 U.S. census and 1976 Dallas City Profile Survey data. The findings indicate that the nondiscrimination policy was not effective in reducing the high levels of racial segregation. A small decline in segregation was noted after a change in project administrative personnel late in 1974.
Date: December 1978
Creator: Weatherby, Norman L.
Partner: UNT Libraries

Study by atomistic theory and high-resolution electron microscopies of Cu atoms at an Al grain boundary

Description: New insight into the atomic segregation of copper to an aluminum grain boundary has been obtained using atomic resolution electron microscopy techniques coupled with ab-initio electronic structure calculations. We find the copper segregation to be site specific, changing the structure of the boundary by unexpectedly occupying interstitial sites. The calculated energy for segregation was found to be sufficient for essentially all of the interstitial sites to be filled. Minor elemental constituents in materials can have profound effects on their engineering performance, often through segregation to grain boundaries in the host material. One important example is the great resistance to electromigration damage in microelectronics imparted by small additions of copper to aluminum interconnects.
Date: February 2, 2003
Creator: Plitzko, Jurgen M.; Campbell, Geoffrey H.; King, Wayne E.; Foiles, Stephen M.; Kisielowski, Christian & Duscher, Gerd
Partner: UNT Libraries Government Documents Department

Copper segregation to the Sigma5 (310)/[001] symmetric tilt grain boundary in aluminum

Description: New insight into the atomic segregation of copper to an aluminum grain boundary has been obtained using multiple, complementary atomic resolution electron microscopy techniques coupled with ab-initio electronic structure calculations. The copper segregation is site specific and changes the structure of the boundary by occupying interstitial sites. Minor elemental constituents in materials can have profound effects on their engineering performance. This change in structure can be associated with these strong effects. The observed structural change will alter the mass transport behavior of the boundary and has implications for the understanding of electromigration mechanisms.
Date: January 1, 2003
Creator: Campbell, Geoffrey H.; Plitzko, Jurgen M.; King, Wayne E.; Foiles, Stephen M.; Kisielowski, Christian & Duscher, Gerd J.M.
Partner: UNT Libraries Government Documents Department

CLASSIC MANY BODY POTENTIAL FOR CONCENTRATED ALLOYS, AND THE INVERSION OF ORDER IN FE-CR

Description: Atomistic simulations of alloys at the classic--or empirical--level face the challenge to correctly model basic thermodynamic properties. In this work we propose a methodology to generalize many-body classic potentials to incorporate complex formation energy curves. Application to Fe-Cr allows us to correctly predict the order vs segregation tendency in this alloy, as observed experimentally and calculated with ab initio techniques, providing in this way a potential suitable for radiation damage studies.
Date: April 14, 2005
Creator: Caro, A; Crowson, D A & Caro, M
Partner: UNT Libraries Government Documents Department

Atomistic Simulations of Grain Boundary Pinning in CuFe Alloys

Description: The authors apply a hybrid Monte Carlo-molecular dynamics code to the study of grain boundary motion upon annealing of pure Cu and Cu with low concentrations of Fe. The hybrid simulations account for segregation and precipitation of the low solubility Fe, together with curvature driven grain boundary motion. Grain boundaries in two different systems, a {Sigma}7+U-shaped half-loop grain and a nanocrystalline sample, were found to be pinned in the presence of Fe concentrations exceeding 3%.
Date: May 22, 2005
Creator: Zepeda-Ruiz, L A; Gilmer, G H; Sadigh, B; Caro, J A & Oppelstrup, T
Partner: UNT Libraries Government Documents Department

Medical Sequencing at the extremes of Human Body Mass

Description: Body weight is a quantitative trait with significantheritability in humans. To identify potential genetic contributors tothis phenotype, we resequenced the coding exons and splice junctions of58 genes in 379 obese and 378 lean individuals. Our 96Mb survey included21 genes associated with monogenic forms of obesity in humans or mice, aswell as 37 genes that function in body weight-related pathways. We foundthat the monogenic obesity-associated gene group was enriched for rarenonsynonymous variants unique to the obese (n=46) versus lean (n=26)populations. Computational analysis further predicted a significantlygreater fraction of deleterious variants within the obese cohort.Consistent with the complex inheritance of body weight, we did notobserve obvious familial segregation in the majority of the 28 availablekindreds. Taken together, these data suggest that multiple rare alleleswith variable penetrance contribute to obesity in the population andprovide a deep medical sequencing based approach to detectthem.
Date: September 1, 2006
Creator: Ahituv, Nadav; Kavaslar, Nihan; Schackwitz, Wendy; Ustaszewski,Anna; Martin, Joes; Hebert, Sybil et al.
Partner: UNT Libraries Government Documents Department

A Family of Zinc Finger Proteins Is Required forChromosome-specific Pairing and Synapsis during Meiosis in C.elegans

Description: Homologous chromosome pairing and synapsis are prerequisitefor accurate chromosome segregation during meiosis. Here, we show that afamily of four related C2H2 zinc-finger proteins plays a central role inthese events in C. elegans. These proteins are encoded within a tandemgene cluster. In addition to the X-specific HIM-8 protein, threeadditional paralogs collectively mediate the behavior of the fiveautosomes. Each chromosome relies on a specific member of the family topair and synapse with its homolog. These "ZIM" proteins concentrate atspecial regions called meiotic pairing centers on the correspondingchromosomes. These sites are dispersed along the nuclear envelope duringearly meiotic prophase, suggesting a role analogous to thetelomere-mediated meiotic bouquet in other organisms. To gain insightinto the evolution of these components, wecharacterized homologs in C.briggsae and C. remanei, which revealed changes in copy number of thisgene family within the nematode lineage.
Date: June 7, 2006
Creator: Phillips, Carolyn M. & Dernburg, Abby F.
Partner: UNT Libraries Government Documents Department

Atomistic studies of grain boundaries and heterophase interfaces in alloys and compounds. Final report, July 1987-August 1998

Description: The overarching goal of the research supported by this grant was investigation of the structure and properties of interfaces in multicomponent systems by atomistic modeling. Initially, the research was devoted to studies of segregation to grain boundaries in binary disordered alloys. The next step was then studies of the structure and properties of grain boundaries in ordered compounds, specifically Ni3Al and NiAl, and grain boundary segregation in these compounds in the case of off-stoichiometry. Finally, the structure of Nb/sapphire interfaces, in particular the core configurations of the misfit dislocations, was studied.
Date: August 1, 1998
Creator: Vitek, Vaclav
Partner: UNT Libraries Government Documents Department

Interface Reactions and Electrical Characteristics of Au/GaSb Contacts

Description: The reaction of Au with GaSb occurs at a relatively low temperature (100 C). Upon annealing, a AuSb{sub 2} compound and several Au-Ga phases are produced. Phase transitions occur toward higher Ga concentration with increasing annealing temperatures. Furthermore, the depth of the contact also increases with increased annealing temperature. They found that the AuSb{sub 2} compound forms on the GaSb surface, with the compound crystal partially ordered with respect to the substrate. The transition of Schottky- to ohmic-contact behavior in Au/n-type GaSb occurs simultaneously with the formation of the AuGa compound at about a 250 C annealing temperature. This ohmic contact forms without the segregation of dopants at the metallic compound/GaSb interface. Therefore it is postulated that transition from Schottky- to ohmic-contact behavior is obtained through a series of tunneling transitions of electrons through defects in the depletion region in the Au/n-type GaSb contacts. Contact resistivities of 6-7 x 10{sup -6} {Omega}-cm{sup 2} were obtained with the annealing temperature between 300 and 350 C for 30 seconds. In Au/p-type GaSb contacts, the resistivity was independent of the annealing temperature. This suggested that the carrier transport in p-type contact dominated by thermionic emission.
Date: July 7, 2000
Creator: Ehsani, H.; Gutmann, R.J. & Charache, G.W.
Partner: UNT Libraries Government Documents Department

Modeling the segregation of hydrogen to lattice defects in nickel

Description: In order to better understand the effect of hydrogen on the fracture behavior of nickel, this study uses the embedded atom method (EAM) to model the segregation of hydrogen to lattice defects in nickel. The dislocations modeled include an edge, a screw, and a Lomer dislocation in the locked configuration, i.e. the Lomer-Cottrell Cock (LCL). Several coincident site lattice boundaries are also investigated, these being the {Sigma}3(112) and {Sigma}11(113) tilt boundaries. It will be shown that the trap site energies in the vicinity of both the edge and screw dislocations is only about 0.1 eV while for the LCL and all of the grain boundaries the maximum trap site energy in the vicinity of the defect is on order 0.3 eV. Using a Monte-Carlo method to a impose a hydrogen environment produces much stronger segregation of hydrogen to the deeper traps. When compared to recent experimental studies showing that a binding energy between 0.3-0.4 eV is required for trap site controlled fracture in IN903, it can be concluded that the embrittlement process is most probably associated with trapping of hydrogen to the Lomer-Cottrell Locks.
Date: May 1, 1995
Creator: Angelo, J.E.; Moody, N.R. & Baskes, M.I.
Partner: UNT Libraries Government Documents Department

[News Script: School integraters]

Description: Script from the WBAP-TV/NBC station in Fort Worth, Texas, covering a news story about the Carrollton school district outlining their plans for integration.
Date: January 16, 1963
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections