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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.
51

Catalytic Oxidation of Toluene in an Air Stream over granular Catalysts

Hsu, Chao-hsiang 18 July 2007 (has links)
Abstract Aluminum oxide was utilized as a carrier of active metals copper and manganese. Catalysts with various metal ratios and weight loadings were produced by incipient impregnation to treattoluene. From the 24 catalysts we prepared, this investigation selected the most effective catalyst, based on the conversion rate of toluene and CO2 yield. The influence of operating parameters of toluene oxidization on the conversion rate and long-term variations in catalytic activity were investigated, and the physical properties of catalysts were determined by SEM and XRD. The conversion rate for toluene and CO2 yield reached 95% when the Cu/Mn catalyst was used with a metal ratio of 1:1 and 20% loading at 350¢XC, an influent toluene concentration of 1000ppm, oxygen concentration of 21%, a space velocity of 12000 hr-1, and relative humidity of 26%. The toluene conversion rate increased as reaction temperature and influent concentration of oxygen increased, but decreased as the initial toluene concentration and space velocity increased. The long-term test proceeded for seven days at a constant influent toluene concentration of 1000ppm, constant oxygen concentration of 21%, constant space velocity of 12000hr-1 and constant relative humidity of 26%. The stability of the Cu/Mn catalyst structure was assessed. Differences between fresh and aged catalysts were analyzed using analytical instruments such as SEM, and XRD. No obvious deactivation of the catalytic surface was detected. Keywords aluminum oxide, Cu/Mn catalyst, toluene, and operational parameters
52

Optical Application of Anodic Aluminum Oxide

Chien, Wei-han 29 July 2008 (has links)
Abstract The AAO membrane with nanopore arrays were fabricated by anodizing highly pure aluminum foils (99.9995%) in electrolyte under steady voltage. Pore diameter can be controlled by different anodic voltage(from 30 to 50 V) and electrolyte, on the other hand, thickness is proportioned to anodizing time , and interpore could follow this rule(a = 15.4+2.63¡Ñv) , and minimum radius of pore could reach 15nm . The XRD spectra of AAO without and with annealing, both showed the diffraction peaks of (311)¡B(400)¡B(440), corresponding to the £^-Al2O3 phase . Before fabricating AAO, we would polish under low temperature and then clean alumina foil in order to reduce surface roughness that is good for better order and regular. Through the use of porous anodic alumina masks, Au nanodot arrays deposited on Si by E-gun with AAO mask. Subsequently, the AAO mask was removed by H3PO4. Under the same procedure, we can fabricate 80nm of the diameter of pore and apply this mask on wafer of laser constructure . Because of regular hexagonal pore array, we may get the photonic crystal effect. During PL experiment, we got the result that AAO could increase light extraction of quantum dot from C237 wafer and controlled emission peak from C238 and C196 wafer and position of peak could shift to 1140nm. We hope nanodot array on wafer of laser structure could control emission peak.
53

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 online.
54

Part I. Surface-enhanced Raman scattering (SERS) methodology and applications to small organic molecules ; Part. II. Luminescence in the Raman spectra of aluminum oxide /

Zuo, Chen, January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains xiii, 139 p. : ill. Vita. Includes abstract. Includes bibliographical references.
55

Growth of thin film water on [alpha]-Al₂O₃ (0001) and its implications for ice nucleation /

Thomas, Alyssa C. January 2009 (has links)
Thesis (Ph.D.)--Ohio University, June, 2009. / Release of full electronic text on OhioLINK has been delayed until June 1, 2010. Includes bibliographical references (leave 107)
56

Growth of thin film water on [alpha]-Al₂O₃ (0001) and its implications for ice nucleation

Thomas, Alyssa C. January 2009 (has links)
Thesis (Ph.D.)--Ohio University, June, 2009. / Title from PDF t.p. Release of full electronic text on OhioLINK has been delayed until June 1, 2010. Includes bibliographical references (leave 107)
57

Modeling of an aluminum reduction cell for the development of a state estimator

Biedler, Philip. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xi, 172 p. : ill. (some col.). Includes abstract. Includes bibliographical references.
58

The production of high alumina refractories bonded with Lumnite refractory cement

Hoffman, Joseph Lewis. January 1940 (has links) (PDF)
Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1940. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed February 22, 2010) Includes bibliographical references (p. 24) and index (p. 25).
59

RADIATION AND TEMPERATURE INFLUENCES ON THE ELECTRICAL CONDUCTIVITY OF ALUMINA

Dau, Gray John, 1938- January 1965 (has links)
No description available.
60

Development of a calcia-alumina-zirconia castable

Smith, Lindsey Keller January 1978 (has links)
No description available.

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