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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.
21

Adsorption of nitric oxide on highly dispersed magnetite

Schorfheide, James John. January 1977 (has links)
Thesis--Wisconsin. / Includes bibliographical references (leaf 59).
22

The activity of zinc oxide in multicomponent slags

Davenport, William George January 1960 (has links)
The activity of zinc oxide in multicomponent slags has been investigated. Activities were determined experimentally Toy equilibrating iron saturated brasses with slags containing iron oxide. Required activities in the Zn-Cu-Fe system were obtained from experimental iron saturation data and available information on the Zn-Cu and Cu-Fe systems. Where measurement was not possible, thermodynamic analyses of slag systems were carried out. Rigid activity patterns in the ZnO-SiO₂, ZnO-FeO-SiO₂, ZnO-CaO-SiO₂ and ZnO-FeO-CaO-SiO₂ systems have been developed from experimental and analytical data. Agreement with the activity data of Bell, Turner and Peters on ZnO-FeO-CaO-SiO₂ and Okunev and Bovykin on ZnO-FeO-SiO₂ type slags indicates that the present measurement technique provides a good basis for industrial slag investigations. / Applied Science, Faculty of / Mining Engineering, Keevil Institute of / Graduate
23

Some properties of aluminum oxide in electrolytic solutions

Urquhart, Helen Mary Ann January 1949 (has links)
By anodic oxidation, an aluminum plate can be covered with an amorphous or crystalline oxide layer, depending on the electrolyte used. The amorphous layer, obtained in a solution of oxalic or sulphuric acid, has a porous structure. However, the pores do not go right down to the aluminum as has been shown by many investigators, but end in a solic insulating layer, the thickness of which may be determined by capacity measurements. Corresponding to a given temperature and solic concentration of the electrolytic solution and a given formation current density, there is only one final capacity obtainable. Increasing the concentration, or temperature, or decreasing the current density, increases the final capacity obtainable. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
24

Particle growth characteristics of MgO

Aihara, Kunio January 1973 (has links)
The particle growth characteristics of active MgO in the size range 70-400 Å have been studied by the x-ray line broadening technique. The starting material was a synthetic magnesium hydroxide, which was decomposed and then heat treated under isothermal conditions in the temperature range 400-900° C in vacuum and in H₂O vapor. The particle growth rate was very much higher in vapor than that in vacuum. The results were analysed by the conventional grain growth equation, Dn=Kt and newly developed models. In these models, surface diffusion, bulk diffusion and evaporation-condensation have been considered for mass transport mechanisms. The activation energy for the particle growth process of MgO in H₂O vapor was calculated to be about 31 Kcal/mole. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate
25

Activity of ZnO in the ternary system ZnO-CaO-SiO2

Fairweather, Michael John January 1967 (has links)
The activity of ZnO in ternary Zno-CaO-SiO₂ slags has been measured at 1300 C by equilibration with copper rich brass and low oxygen potential gas utilizing the following reversible galvanic cell: Pt I H₂,H₂O |0.85Zr0₂-0.15CaO | 0₂(Air)|Pt Thermodynamic data on the component binaries was employed to calculate the excess free energy of the ternary system and the isoactivity patterns of the three components at 1600 C with respect to the metastable pure liquid standard states. An estimate of 6 E.U. was made for the entropy of fusion of ZnO. The measured activities are in good agreement with the calculated values. The proposed excess free energy contours in the Zno-CaO-SiO₂ ternary are similar in shape to those calculated in a similar manner for the FeO-CaO-SiO₂ system. Also the calculated zinc oxide isoactivity figure resembles the ferrous oxide isoactivity diagram. This zinc oxide isoactivity pattern projects towards the lime orthosilicate composition. This shape is characteristic of FeO, but in the case of ZnO the projection is less pronounced. Both these observations are in keeping with the slightly more basic behaviour of zinc oxide. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate
26

Formation of MgO nanorods by displacement reactions between Mg and ZnO. / 鎂和氧化鋅反應製備氧化鎂納米棒 / Formation of MgO nanorods by displacement reactions between Mg and ZnO. / Mei he yang hua xin fan ying zhi bei yang hua mei na mi bang

January 2004 (has links)
Yau Man Yan Eric = 鎂和氧化鋅反應製備氧化鎂納米棒 / 游文仁. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / Yau Man Yan Eric = Mei he yang hua xin fan ying zhi bei yang hua mei na mi bang / You Wenren. / Acknowledgement --- p.i / Abstract --- p.ii / 摘要 --- p.iii / Table of contents --- p.iv / List of tables --- p.viii / List of figures --- p.ix / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Nanostructured materials --- p.1-1 / Chapter 1.2 --- Application of nano-materials --- p.1-1 / Chapter 1.3 --- Current development of nano-materials --- p.1-2 / Chapter 1.4 --- Synthesis of nano-materials --- p.1-2 / Chapter 1.4.1 --- Physical methods --- p.1-3 / Chapter 1.4.1.1 --- Physical vapor deposition --- p.1-3 / Chapter 1.4.1.2 --- Arc-discharge process --- p.1-3 / Chapter 1.4.1.3 --- Laser ablation --- p.1-4 / Chapter 1.4.2 --- Chemical methods --- p.1-4 / Chapter 1.4.2.1 --- Chemical vapor deposition --- p.1-4 / Chapter 1.4.2.2 --- Metal-organic chemical vapor deposition (MOCVD) --- p.1-4 / Chapter 1.4.2.3 --- Solgel method --- p.1-5 / Chapter 1.5 --- Study on growth mechanism of nano-materials --- p.1-5 / Chapter 1.5.1 --- Vapor-liquid-solid (VLS) mechanism --- p.1-5 / Chapter 1.5.2 --- Vapor-solid (VS) mechanism --- p.1-6 / Chapter 1.6 --- Applications of Magnesium Oxide (MgO) materials --- p.1-7 / Chapter 1.7 --- Previous works on MgO nanostructures --- p.1-8 / Chapter 1.7.1 --- Network like MgO nanobelts --- p.1-8 / Chapter 1.7.2 --- Decorated MgO crystalline fibers --- p.1-9 / Chapter 1.7.3 --- Mg2Zn11 - MgO belt-like nanocables --- p.1-9 / Chapter 1.7.4 --- MgO nanowires with uniform diameter distribution --- p.1-10 / Chapter 1.7.5 --- Aligned MgO nanorods on MgO (100) substrates --- p.1-11 / Chapter 1.8 --- Objectives and approaches of this project --- p.1-12 / Chapter 1.8.1 --- Addition of sodium chloride (NaCl) --- p.1-13 / Chapter 1.9 --- Thesis Layout --- p.1-13 / Chapter 1.10 --- References --- p.1-15 / Chapter Chapter 2 --- Methodology and Instrumentation / Chapter 2.1 --- Introduction --- p.2-1 / Chapter 2.2 --- Powder Metallurgy --- p.2-1 / Chapter 2.3 --- Sample fabrication --- p.2-1 / Chapter 2.3.1 --- Starting materials --- p.2-1 / Chapter 2.3.2 --- Cold pressing --- p.2-2 / Chapter 2.3.2.1 --- Single pellet method --- p.2-2 / Chapter 2.3.2.2 --- Double pellet method --- p.2-3 / Chapter 2.3.3 --- Argon tube furnace sintering --- p.2-3 / Chapter 2.4 --- Study of fabrication parameters --- p.2-4 / Chapter 2.4.1 --- Heat treatment temperature --- p.2-4 / Chapter 2.4.2 --- NaCl content in sample --- p.2-4 / Chapter 2.4.3 --- Duration of heat treatment --- p.2-5 / Chapter 2.5 --- Control Experiments --- p.2-5 / Chapter 2.5.1 --- Effect of addition of NaCl --- p.2-5 / Chapter 2.5.2 --- Effect of residual oxygen --- p.2-5 / Chapter 2.5.3 --- Geometrical effect of experimental setup --- p.2-6 / Chapter 2.5.3.1 --- Compressed double pellet method --- p.2-6 / Chapter 2.5.3.2 --- Powder on Magnesium pellet method --- p.2-6 / Chapter 2.5.3.3 --- Single pellet method --- p.2-7 / Chapter 2.6 --- Characterization Methods --- p.2-7 / Chapter 2.6.1 --- Thermal analysis - Differential thermal analyzer (DTA) --- p.2-7 / Chapter 2.6.2 --- Structural analysis --- p.2-7 / Chapter 2.6.2.1 --- Scanning electron microscopy (SEM) --- p.2-7 / Chapter 2.6.2.2 --- Transmission electron microscopy (TEM) --- p.2-8 / Chapter 2.6.3 --- Phases determination - X-ray powder diffractometry (XRD) --- p.2-8 / Chapter 2.7 --- References --- p.2-9 / Chapter Chapter 3 --- Results of Mg-ZnO-NaCl System / Chapter 3.1 --- Introduction --- p.3-1 / Chapter 3.2 --- Results of thermal analysis --- p.3-1 / Chapter 3.2.1 --- Chemical reactions --- p.3-1 / Chapter 3.2.2 --- DTA results --- p.3-2 / Chapter 3.3 --- Variation of heat treatment temperature --- p.3-3 / Chapter 3.3.1 --- XRD pattern --- p.3-3 / Chapter 3.3.2 --- SEM images --- p.3-4 / Chapter 3.4 --- Variation of NaCl content --- p.3-5 / Chapter 3.4.1 --- TEM analysis --- p.3-5 / Chapter 3.5 --- Variation of duration of heat treatment --- p.3-6 / Chapter 3.6 --- Additional findings --- p.3-7 / Chapter 3.7 --- Discussions --- p.3-7 / Chapter 3.8 --- References --- p.3-10 / Chapter Chapter 4 --- Results of Control Experiments / Chapter 4.1 --- Introduction --- p.4-1 / Chapter 4.2 --- The study of Mg-ZnO system --- p.4-1 / Chapter 4.3 --- The study of residual oxygen effect --- p.4-2 / Chapter 4.4 --- The study of geometrical effect of experiment setup --- p.4-2 / Chapter 4.5 --- Discussions --- p.4-3 / Chapter 4.5.1 --- Effect of addition of NaCl --- p.4-3 / Chapter 4.5.2 --- Effect of residual oxygen --- p.4-3 / Chapter 4.5.3 --- Role of ZnO --- p.4-4 / Chapter 4.5.4 --- Growth model --- p.4-4 / Chapter 4.6 --- References --- p.4-7 / Chapter Chapter 5 --- Conclusions and Further Studies / Chapter 5.1 --- Conclusion --- p.5-1 / Chapter 5.2 --- Further studies --- p.5-2 / Chapter 5.3 --- References --- p.5-3
27

Effects of aluminum and zirconia contents on the reaction bonded aluminum oxide process /

Sheedy, Paul Martin, January 2002 (has links)
Thesis (Ph. D.)--Lehigh University, 2003. / Includes vita. Includes bibliographical references (leaves 165-174).
28

Laboratory studies of potentially important atmospheric processes involving oxides of nitrogen

Estupiñán, Edgar G. 08 1900 (has links)
No description available.
29

Capacitance-voltage spectroscopy in metal-tantalum pentoxide (Ta-O)-silicon mos capacitors/

Özdağ, Pınar. Güneş, Mehmet January 2005 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology, İzmir, 2005 / Keywords: Capacitance-voltage spectroscopy, high dielectric constant insulators, tantalum pentoxide. Includes bibliographical references (leaves 92-97)
30

Regulation of the human neuronal nitric oxide synthase gene via alternate promoters

Hartt, Gregory Thomas, January 2003 (has links)
Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xii, 152 p.; also includes graphics (some col.). Includes bibliographical references (p. 137-150). Available online via OhioLINK's ETD Center

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