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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.
61

Processing and characterization of microstructurally biased two-phase titanium diboride/alumina ceramica (TiB₂+Al₂O₃)

Ferranti, Louis, Jr. 12 1900 (has links)
No description available.
62

An investigation of the deformation of anodic aluminium oxide nano-honeycomb during nanoindentation

Ng, King-yeung. January 2009 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 138-139). Also available in print.
63

Preparation, characterization, and activity of mono-dispersed supported catalylsts [sic]

Hicks, Tanya Temaca. January 2004 (has links) (PDF)
Thesis (M.S.)--Chemical Engineering, Georgia Institute of Technology, 2005. / Agrawal, Pradeep K., Committee Chair ; Bommarius, Andreas S., Committee Member ; Schork, F. Joseph, Committee Member. Includes bibliographical references.
64

A phase rule study of the system lime-potash-alumina

Brownmiller, Lorrin Thomas, January 1935 (has links)
Thesis (Ph. D.)--Columbia University, 1935. / Vita. Bibliography: p. 27.
65

Experimental and numerical study of crack bridging in polycrystalline ceramics at room and elevated temperatures /

Tran, Duc Khanh. January 1999 (has links)
Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 127-140).
66

Geological setting and genesis of the Eastern Avalon High Alumina Belt /

Hayes, John P. January 1996 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 1997. / Bibliography: leaves 171-189. Also available online.
67

The use of activated alumina for reclaiming and reconditioning turbine, transformer and circuit breaker oils

English, Thomas Odie. January 1935 (has links) (PDF)
Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1935. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed July 15, 2010) Includes index (p. 23-24).
68

Diagnostic tools for HVOF process optimization /

Turunen, Erja. January 1900 (has links) (PDF)
Thesis (doctoral)--Helsinki University of Technology, 2005. / Includes bibliographical references. Also available on the World Wide Web. Myös verkkojulkaisuna.
69

Phosphorus in alum amended poultry litter systems distribution, speciation, and interactions with aluminum oxides /

Staats, Kristin Estelle. January 2005 (has links)
Thesis (M.S.)--University of Delaware, 2005. / Principal faculty advisor: Donald L. Sparks, Dept. of Plant & Soil Sciences. Includes bibliographical references.
70

Desenvolvimento e caracterização de cerâmicas coloridas para uso ortodôntico à base de alumina associada ao feldspato / Development and characterization of colored alumina-based ceramic associated with feldspar for orthodontic use

Macedo, Érika de Oliveira Dias de January 2013 (has links)
Esta tese teve como objetivo desenvolver e caracterizar peças cerâmicas obtidas a partir de pós de alumina nas cores rosa e azul, produzidos por processo experimental. O desenvolvimento deste novo processo de produção gerou a necessidade de proteção realizada por meio de pedido de depósito de patente. Os pós produzidos foram caracterizados quanto à distribuição granulométrica e conformados por prensagem uniaxial em discos com 12 (±0,2)mm de diâmetro e 1,2 (±0,2)mm de espessura e os protocolos de sinterização foram definidos em função da cor e da concentração do aditivo utilizado. O feldspato foi escolhido como aditivo de sinterização para que a mesma ocorresse via fase líquida. Ele foi adicionado nas concentrações de 10, 15 e 20% tanto para os grupos de cor rosa (grupos R10, R15 e R20) quanto para os de cor azul (grupos A10, A15 e A20). Após a sinterização as peças foram analisadas quanto ao módulo de elasticidade, microdureza Vickers, rugosidade de superfície e tenacidade à fratura. O módulo de elasticidade variou de 183,2 a 157 GPa, nos grupos de cor rosa, e nos grupos de cor azul os valores variaram de 101,1 a 176,6 GPa. A rugosidade apresentou valores entre 0, 43 e 0,72 μm para os grupos de cor rosa e 0,39 e 0,6 μm para os grupos de cor azul. A dureza Vickers variou de 418,7 a 623,1 para a cor rosa e de 366,9 a 632 para cor azul. A tenacidade média para os grupos de cor rosa variou de 0,72 a 1,97 MPa.m1/2 e de 0,82 a 1,9 MPa.m1/2 para os grupos de cor azul. O grupo R10 apresentou valores médios de rugosidade significativamente maiores tanto em relação ao grupo R20 quanto ao grupo A10. As demais concentrações não apresentaram diferença significativa em relação às cores. A média dos valores de dureza do grupo A10 foi significativamente maior em relação às demais concentrações na mesma cor, no entanto não houve diferença quando comparado ao grupo R10. Os valores médios do módulo de elasticidade foram significativamente maiores nos grupos de cor rosa em relação aos grupos de cor azul para as mesmas concentrações com exceção do grupo R20 que apresentou valores menores, porém sem significância estatística. A tenacidade à fratura apresentou diferença estatística significativa apenas na comparação entre os grupos R10 e R20. Os valores de tenacidade mais próximos ao relatado pela literatura foram apresentados pelos grupos R20 e A20, porém há diferenças nos métodos de análise da tenacidade entre os estudos. As peças de cor azul com 10% de feldspato apresentaram os resultados mais favoráveis tanto em comparação com as diferentes concentrações na mesma cor quanto entre as diferentes cores. / The aim of this thesis was to develop and characterize ceramic pieces obtained from alumina powders in pink and blue colors produced by experimental procedure. The development of this new production process led to the need for protection of the knowledge generated thus an application for patent was done. The powders produced were characterized for particle size distribution and uniaxial pressed into discs with 12 (± 0.2) mm in diameter and 1.2 (± 0.2) mm thick. The sintering protocols were defined according to the color and concentration of the additive used. For sintering to happen into liquid fase the feldspar was chosen as a sintering additive. It was added at concentrations of 10, 15 and 20% for both pink (R10, R15 e R20) and blue (A10, A15 e A20) groups. After the sintering process an analysis of the elastic modulus, the Vickers hardness, surface roughness and fracture toughness of the samples were performed. The elastic modulus values ranged from 183.2 to 157 GPa in pink groups and 101.1 to 176.6 GPa in blue groups. The roughness mean varied between 0,43 and 0,72 μm in pink groups and between 0.39 and 0.6 μm in blue groups. The Vickers hardness number ranged from 418.7 to 623.1 in pink groups and from 366,9 a 632 in blue groups. The fracture toughness mean to pink groups ranged from 0.72 a 1.97 MPa.m1/2 and from 0.82 a 1.9 MPa.m1/2 to blue groups. The R10 group had significantly higher roughness mean values when compared to the groups R20 and A10. No significant difference was found on the others groups. The hardness average values of the A10 group were significantly higher when compared to other concentrations on the same color, however there was no difference when compared to the R10 group. The average values of the elastic modulus were significantly higher in pink groups when compared to blue groups for the same concentrations except the R20 group that showed lower values, but without statistical significance. The fracture toughness results showed a statistically significant difference when R10 and R20 groups were compared. The toughness values closer to those reported in the literature were presented by R20 and A20 groups, but there are differences in the methods of analysis of toughness between studies. The blue pieces with 10% of feldspar showed the most favorable results compared both between different concentrations of the same color as between different colors at the same concentration.

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