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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.
1

Properties of Semigroups

Donnell, William Anthony 06 1900 (has links)
This paper is an introductory, algebraic study of semigroups.
2

The relation between tensile strength and density of pariffin wax at various temperatures

Inouye, Kuramitsu January 1934 (has links)
[No abstract available] / Science, Faculty of / Chemistry, Department of / Graduate
3

Studies on thermal stabilities of transparent dielectrics/ZnO heterostructures. / 透明电解质/氧化锌异质结热稳定性的研究 / Studies on thermal stabilities of transparent dielectrics/ZnO heterostructures. / Tou ming dian jie zhi/yang hua xin yi zhi jie re wen ding xing de yan jiu

January 2007 (has links)
Wang, Ranshi = 透明电解质/氧化锌异质结热稳定性的研究 / 王然石. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 130-134). / Abstracts in English and Chinese. / Wang, Ranshi = Tou ming dian jie zhi/yang hua xin yi zhi jie re wen ding xing de yan jiu / Wang Ranshi. / Chapter I. --- Abstract / Chapter II. --- Acknowledgement / Chapter III. --- Table of contents / Chapter IV. --- List of figures / Chapter V. --- List of tables / Chapter 1 --- Introduction / Chapter 1.1 --- Motivations / Chapter 1.2 --- Outline of thesis / Chapter 2 --- Experimental Conditions and Techniques Used / Chapter 2.1 --- Sample preparation / Chapter 2.1.1 --- Radio frequency magnetic sputtering / Chapter 2.1.2 --- ITO glass / Chapter 2.1.3 --- Thermal evaporation / Chapter 2.1.4 --- Thermal annealing / Chapter 2.2 --- Optical characterization of ZnO / Chapter 2.2.1 --- Photoluminescence (PL) measurement / Chapter 2.2.2 --- SEM and cathodoluminescence spectroscopy / Chapter 2.3 --- Time-of-FIight Secondary Ion Mass Spectroscopy (TOF-SIMS ) / Chapter 2.4 --- Electrical measurements / Chapter 3 --- Calibrations / Chapter 3.1 --- Sample Thickness / Chapter 3.2 --- Calibrations of cathodeluminescence measurements / Chapter 3.2.1 --- Probe current and specimen current / Chapter 3.2.2 --- Sample uniformity in CL measurement / Chapter 3.2.3 --- Mirror position / Chapter 3.2.4 --- Non-linear relation between CL emission and current / Chapter 3.2.5 --- CL band-edge emission stability / Chapter 3.2.6 --- Effect of magnification / Chapter 3.2.7 --- Effect of electron beam shift / Chapter 3.2.8 --- Conclusions / Chapter 3.3 --- C-V measurement / Chapter 4 --- Experimental Results and Data Analysis / Chapter 4.1 --- Optical properties / Chapter 4.1.1 --- Luminescence of ZnO / Chapter 4.1.2 --- Light emitting thermal stability of A10x (MgO) capped ZnO film / Chapter 4.1.2.1 --- Emission degradations in annealing treatment by PL / Chapter 4.1.2.2 --- Evidence about the interface degradation / Chapter 4.1.2.3 --- CL studies of the emission from sample surface / Chapter 4.2 --- Secondary Ion Mass Spectroscopy (SIMS) studies of AIOx-capped ZnO / Chapter 4.2.1 --- Data processing / Chapter 4.2.2 --- Diffusion width / Chapter 4.3 --- Simulation of Zn out diffusion to the dielectric layer / Chapter 4.3.1 --- Structure and assumptions / Chapter 4.3.2 --- Calculations of diffusion by Fick's Law / Chapter 4.3.3 --- Simulation of PL reduction from diffusion / Chapter 4.3.4 --- Short-time PL / Chapter 4.4 --- Simulation of defects generation in emission reduction process / Chapter 4.4.1 --- Some calculations of continuity equation / Chapter 4.4.2 --- First order equation for defect generation / Chapter 4.5 --- Electrical measurements / Chapter 4.5.1 --- Theory of C-V measurement for MOS structure / Chapter 4.5.1.1 --- MOS Structure / Chapter 4.5.1.2 --- Discussions about surface charge and energy level in C-V experiments of MOS / Chapter 4.5.1.3 --- Useful formulations / Chapter 4.5.2 --- Experimental results of C-V and parameter extraction / Chapter 4.5.2.1 --- Effect of series resistance correction / Chapter 4.5.2.2 --- Effect of thermal annealing to C-V curves on dielectric/ZnO/ITO / Chapter 4.5.2.3 --- Doping concentration (ND) / Chapter 4.5.2.4 --- Discussion about the fixed and mobile charge / Chapter 4.5.3 --- Simulation of C-V relation in dielectric/ZnO / Chapter 4.5.4 --- Current-voltage (I-V) measurements / Chapter 4.5.5 --- Conductance-voltage measurements (G-V) and interface trap density / Chapter 4.5.6 --- DLTS measurements for extracting interface trap density / Chapter 5 --- Discussions and Conclusion / Chapter 5.1 --- Mechanism / Chapter 5.2 --- Conclusions / Chapter 5.3 --- Future plan / Chapter 6 --- References
4

Magneto-optical properties of superparamagnetic spinel ferrite nanoparticles

Anderson, Richard M. 08 1900 (has links)
No description available.
5

Lightweight foamed concrete (LFC) thermal and mechanical properties at elevated temperatures and its application to composite walling system

Othuman Mydin, Md Azree January 2010 (has links)
LFC is cementatious material integrated with mechanically entrained foam in the mortar slurry which can produce a variety of densities ranging from 400 to 1600 kg/m3. The application of LFC has been primarily as a filler material in civil engineering works. This research explores the potential of using LFC in building construction, as non-load-bearing partitions of lightweight load-bearing structural members. Experimental and analytical studies will be undertaken to develop quantification models to obtain thermal and mechanical properties of LFC at ambient and elevated temperatures. In order to develop thermal property model, LFC is treated as a porous material and the effects of radiant heat transfer within the pores are included. The thermal conductivity model results are in very good agreement with the experimental results obtained from the guarded hot plate tests and with inverse analysis of LFC slabs heated from one side. Extensive compression and bending tests at elevated temperatures were performed for LFC densities of 650 and 1000 kg/m3 to obtain the mechanical properties of unstressed LFC. The test results indicate that the porosity of LFC is mainly a function of density and changes little at different temperatures. The reduction in strength and stiffness of LFC at high temperatures can be predicted using the mechanical property models for normal weight concrete provided that the LFC is based on ordinary Portland cement. Although LFC mechanical properties are low in comparison to normal weight concrete, LFC may be used as partition or light load-bearing walls in a low rise residential construction. To confirm this, structural tests were performed on a composite walling system consisting of two outer skins of profiled thin-walled steel sheeting with LFC core under axial compression, for steel sheeting thicknesses of 0.4mm and 0.8mm correspondingly. Using these test results, analytical models are developed to calculate the maximum load-bearing capacity of the composite walling, taking into consideration the local buckling effect of the steel sheeting and profiled shape of the LFC core. The results of a preliminary feasibility study indicate that LFC can achieve very good thermal insulation performance for fire resistance. A single layer of 650 kg/m3 density LFC panel of about 21 mm would be able to attain 30 minutes of standard fire resistance rating, which is comparable to gypsum plasterboard. The results of a feasibility study on structural performance of a composite walling system indicates that the proposed panel system, using 100mm LFC core and 0.4mm steel sheeting, has sufficient load carrying capacity to be used in low-rise residential construction up to four-storeys.
6

Inter-band magneto-optical studies of III-V semiconductors

Priest, Andrew Nicholas January 1998 (has links)
No description available.
7

Evaluation of Brassica fibre for textile and spinning properties

Khan, Md Rabiul Islam 13 September 2016 (has links)
Brassica napus L., which is commonly known as canola, is the largest sources of edible oil in Canada. The remaining plant material, such as the stem, remains unused for any immediate application and is returned to the soil for decomposition. An investigation has been conducted to extract, characterize and modify the fibre materials from B. napus stems for textile and apparel applications. In order to find the optimum retting conditions for retting time, four different retting parameters were evaluated including, retting temperature, material liquor ratio, water exchange and the reuse of retted water. It was discovered that the virgin-retted fibres from Brassica plants exhibit most of the required textile properties including dye absorbency, strength, and thermal behaviour. However, the virgin-retted fibres do not exhibit the required spinning (yarn transformation) properties (softness, flexibility and individual fibre entity). In order to modify the Brassica fibres for spinnability, three treatment methods were applied: 1) alkali, acid and softener treatment; 2) pectinase enzyme treatment; and 3) enhanced enzyme treatment. According to Method 5 of the American Association of Textile Chemists and Colorists (AATCC), Brassica fibers obtained from treatments 2 and 3 showed similar spinning properties, and demonstrated superior spinning properties to Brassica fibres obtained from treatment one. To determine the variability of the cultivars upon textile and spinning properties, seeds from twenty different Brassica cultivars consisting of three different species, B. napus, B. juncea L. and B. rapa L., were collected, planted, and harvested upon reaching physiological maturity. The virgin water-retted fibre samples were then treated with pectinase enzyme, and different spinning properties (stiffness, softness, individual fibre entity) and textile properties (fibre decomposition temperature, tenacity and dye absorbency) of enzyme-treated samples were evaluated. The current research suggests that producing fibers from canola stubble and stems could be an additional income source for canola growers. / October 2016
8

Thermophysical and Mechanical Properties of Polymer Liquid Crystals and Their Blends

López, Betty Lucy 05 1900 (has links)
Tensile properties, namely the elastic modulus, tensile strength, percent of elongation at yield and at the break were determined for the pure components and blends. The results are connected to the respective phase diagrams and demonstrate that blending makes property manipulation possible. Blends for which the mechanical properties are better than those of pure EPs can be obtained.
9

Thermal properties of nanostructured Pd₈₂Si₁₈ alloy. / 納米鈀硅合金的熱性質 / Thermal properties of nanostructured Pd₈₂Si₁₈ alloy. / Na mi ba gui he jin de re xing zhi

January 2000 (has links)
Chan Chun Wai = 納米鈀硅合金的熱性質 / 陳進偉. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 18-20). / Text in English; abstracts in English and Chinese. / Chan Chun Wai = Na mi ba gui he jin de re xing zhi / Chen Jinwei. / Acknowledgements --- p.III / Abstract --- p.IV / 摘要 --- p.V / Chapter Chapter One ´ؤ --- Introduction / Chapter 1.1 --- Novel materials in the 21st century --- p.1 / Chapter 1.2 --- What are Nanocrystalline Materials? --- p.1 / Chapter 1.3 --- The superior properties of Nanocrystalline Materials --- p.2 / Chapter 1.4 --- Fabrication of Nanocrystalline Materials --- p.3 / Chapter 1.5 --- Flaws of the as-produced Nanophase Materials --- p.4 / Chapter 1.6 --- Theory of Phase Separation --- p.4 / Chapter 1.7 --- Nucleation and Growth --- p.6 / Chapter 1.7.1 --- Homogeneous nucleation / Chapter 1.7.2 --- Heterogeneous nucleation / Chapter 1.8 --- Spinodal Decomposition / Chapter 1.8.1 --- How SD differs from the classical diffusion process? / Chapter 1.8.2 --- Dynamics of SD / Chapter 1.8.3 --- How can we distinguish SD from Nucleation and Growth? / Chapter 1.8.4 --- Pore-free nanophase materials produced by Liquid Phase SD / Chapter 1.9 --- Thermal properties of the pore-free nanostructured Pd82Si18 Alloy --- p.12 / Chapter 1.9.1 --- A review of grain growth in nanophase materials / Chapter 1.9.2 --- Grain growth study on LSD Pd82Si18 alloy 一 aim and prospect / References --- p.18 / Figures --- p.21 / Chapter Chapter Two 一 --- Experimental / Chapter 2.1 --- Introduction --- p.28 / Chapter 2.2 --- From preparation of samples to microstructure analysis --- p.28 / Chapter 2.2.1 --- Alloying / Chapter 2.2.2 --- Fluxing / Chapter 2.2.3 --- Rapid Solification / Chapter 2.2.4 --- Annealing / Chapter 2.2.5 --- Microstructure analysis / Figures --- p.31 / Chapter Chapter Three ´ؤ --- Results and discussions / Thermal stability of bulk nanostructured alloys prepared by liquid phase spinodal decomposition --- p.34 / References --- p.40 / Table --- p.43 / Figures --- p.44 / Chapter Chapter Four ´ؤ --- Conclusions --- p.61
10

Mechanical properties of nanostructured Pd₈₂Si₁₈ alloy. / 納米鈀硅合金之機械特性 / Mechanical properties of nanostructured Pd₈₂Si₁₈ alloy. / Na mi ba gui he jin zhi ji xie te xing

January 2001 (has links)
by Ng Kwok Leung = 納米鈀硅合金之機械特性 / 吳國良. / Thesis submitted in 2000. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / by Ng Kwok Leung = Na mi ba gui he jin zhi ji xie te xing / Wu Guoliang. / Acknowledgements --- p.ii / Abstract --- p.iii / 摘要 --- p.iv / Chapter Chapter 0 --- Prelude- A brief history of materials --- p.1 / Chapter Chapter 1 --- Introduction --- p.4 / Chapter 1.1 --- Introduction --- p.4 / Chapter 1.2 --- How are nanostructured materials produced? --- p.5 / Chapter 1.3 --- General properties of nanostructured materials --- p.7 / Chapter 1.4 --- Mechanical behaviour of nanostructured materials --- p.8 / Chapter 1.5 --- The solution --- p.12 / References --- p.20 / Figures --- p.22 / Chapter Chapter 2 --- Experimental --- p.30 / Chapter 2.1 --- Specimen preparation --- p.30 / Chapter 2.2 --- Means of analysis --- p.32 / Figures --- p.36 / Chapter Chapter 3 --- Synthesis of large nanostructured Pd82Si18 alloy --- p.39 / Abstract --- p.39 / References --- p.44 / Table and Figures --- p.45 / Chapter Chapter 4 --- Tensile behaviour of nanocrystalline Pd82Si18 alloy --- p.54 / Introduction --- p.54 / Experimental --- p.55 / Results --- p.57 / Discussions --- p.58 / References --- p.59 / Table and Figures --- p.60

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