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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.
121

The kinetics of hydrodemetallation of metalloporphyrins.

Hung, Chi-Wen January 1979 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Bibliography: leaves 252-265. / Ph.D.
122

Formation and crystallization kinetics of Fe-B network alloy. / 鐵硼網狀合金的形成和結晶動力學 / Formation and crystallization kinetics of Fe-B network alloy. / Tie peng wang zhuang he jin de xing cheng he jie jing dong li xue

January 2012 (has links)
Fe-B熔體可鑄造成網絡狀合金的微觀結構。研究顯示,熔融狀態的Fe₈₄B₁₆在275 K 過冷時將發生形態轉變。實驗結果指出熔融狀態的Fe-B合金存在一亞穏液態互溶區。該互溶區範圍為Fe₈₄B₁₄.到Fe₈₂B₁₈.。Fe-B網絡狀合金的微觀結構,由一個易碎的Fe₃B子網絡和一個具延展性的αFe子網絡組成。因此Fe-B網絡狀合金擁有具吸引性的物理性能。 / 由於Fe₈₄B₁₆網絡狀合金並不存在任何微孔,因此我們可推斷合金在結晶的過程中,兩個子網絡的固體/液體界面將一起生長。而且,在固體/液體界面前並不具有硼原子的濃度梯度。因此我們提出了一個生長模型來分析Fe-B網絡狀合金來自掃瞄電子顯微鏡和透射電子顯微鏡的檢測結果。Fe-B網絡狀合金的結晶動力學和微觀結構均得到解釋。研究顯示,合金中的兩個子網絡均擁有特定的生長方向,並且以樹枝晶的方式來生長。 / Molten Fe₁₀₀-{U+2093}B{U+2093} melts, where x = 14 to 18, can be cast into ingots of network morphology. It was found that there is a morphological transition in molten Fe₈₄B₁₆.with undercooling of 275 K. The experimental results indicate that there is a metastable liquid miscibility gap in undercooled Fe-B melts. The network morphology consists of two interconnected subnetworks, which are αFe subnetwork and Fe₃B subnetwork respectively. The Fe-B network alloys have attractive mechanical properties. / As micropore does not exist in the Fe₈₄B₁₆ network ingot, it is proposed that the solid/liquid interfaces of the two subnetworks advance together during solidification. In addition, there is no composition gradient of boron atoms at the growth front. A growth model is proposed to explain the results by scanning electron microscopy and transmission electron microscopy. It was found that there is special crystallinity in Fe₈₄B₁₆ network ingots. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Wong, Tak Cheung = 鐵硼網狀合金的形成和結晶動力學 / 黃德彰. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references. / Abstracts also in Chinese. / Wong, Tak Cheung = Tie peng wang zhuang he jin de xing cheng he jie jing dong li xue / Huang Dezhang. / Abstract --- p.ii / Acknowledge --- p.iv / List of Table --- p.vii / List of Figures --- p.viii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Phase diagram --- p.1 / Chapter 1.1.1 --- Undercooling --- p.1 / Chapter 1.2 --- Nucleation and Growth --- p.2 / Chapter 1.2.1 --- Homogeneous Nucleation --- p.3 / Chapter 1.2.2 --- Heterogeneous Nucleation --- p.3 / Chapter 1.2.3 --- Growth --- p.6 / Chapter 1.2.3.1 --- Growth of Pure Metal --- p.6 / Chapter 1.2.3.2 --- Solid/Liquid interface stability --- p.7 / Chapter 1.2.3.3 --- Solidification of Single Phase Binary Alloys --- p.8 / Chapter 1.2.3.3.1 --- Equilibrium Solidification --- p.8 / Chapter 1.2.3.3.2 --- Non-Equilibrium Solidification --- p.8 / Chapter 1.2.3.3.3 --- Morphology Change --- p.9 / Chapter 1.2.3.4 --- Solidification of the Binary Eutectic Alloy --- p.10 / Chapter 1.2.3.4.1 --- Growth of Lamellar Eutectics --- p.10 / Chapter 1.2.3.4.2 --- Off-Eutectic Alloys --- p.11 / Chapter 1.3 --- Binary Systems with a Solid Miscibility Gap --- p.11 / Chapter 1.4 --- Phase Separation Mechanisms in a Solid Miscibility Gap --- p.12 / Chapter 1.4.1 --- Nucleation and Growth --- p.12 / Chapter 1.4.2 --- Spinodal Decomposition --- p.13 / Chapter 1.4.4.1 --- The initiation of Spinodal Decomposition --- p.13 / Chapter 1.4.4.2 --- Diffusion Equation of Spinodal Decomposition --- p.14 / Chapter 1.4.4.3 --- Solution to the Modified Diffusion Equation --- p.17 / Figures --- p.18 / References / Chapter Chapter 2 --- Experimental --- p.29 / Chapter 2.1 --- Preparation of fused silica tube --- p.29 / Chapter 2.2 --- Alloying and fluxing --- p.29 / Chapter 2.3 --- Undercooling --- p.30 / Chapter 2.4 --- Sample Preparation --- p.31 / Chapter 2.4.1 --- Cutting, Grinding and Polishing --- p.31 / Chapter 2.4.2 --- Sample preparation for Scanning Electron Microscopy (SEM) --- p.32 / Chapter 2.4.3 --- Sample preparation for Transmission Electron Microscopy (TEM) --- p.32 / Chapter 2.5 --- Microhardness Test --- p.33 / Chapter 2.6 --- Compression Test --- p.33 / Chapter 2.7 --- Microstructure Analysis --- p.34 / Chapter 2.7.1 --- Scanning Electron Microscopy Analysis --- p.34 / Chapter 2.7.2 --- Transmission Electron Microscopy Analysis --- p.34 / Chapter 2.7.3 --- Indexing Diffraction Patterns --- p.34 / Figures --- p.36 / Chapter Chapter 3 --- Formation of Fe-B network alloys --- p.38 / Chapter 3.1 --- Abstract --- p.38 / Chapter 3.2 --- Introduction --- p.39 / Chapter 3.3 --- Experimental --- p.40 / Chapter 3.4 --- Results --- p.42 / Chapter 3.5 --- Discussion --- p.47 / Chapter 3.6 --- Conclusions --- p.48 / Figures --- p.50 / References --- p.69 / Chapter Chapter 4 --- SEM and TEM studies of Fe84B16 70 alloys of network morphology --- p.70 / Chapter 4.1 --- Abstract --- p.70 / Chapter 4.2 --- Introduction --- p.71 / Chapter 4.3 --- Background --- p.71 / Chapter 4.4 --- Experimental --- p.73 / Chapter 4.5 --- Results --- p.74 / Chapter 4.6 --- Discussions --- p.81 / Chapter 4.7 --- Conclusions --- p.85 / Figures --- p.87 / References --- p.106
123

Crystallization kinetics in Fe-C-Si =: 鑄鐵的結晶動力學. / 鑄鐵的結晶動力學 / Crystallization kinetics in Fe-C-Si =: Zhu tie de jie jing dong li xue. / Zhu tie de jie jing dong li xue

January 2009 (has links)
Cheng, Lai Fung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaf 79). / Abstracts in English and Chinese. / Cheng, Lai Fung. / Chapter Chapter1 --- Introduction --- p.1 / Chapter 1.1 --- Phase diagram determination --- p.1 / Chapter 1.2 --- Formation of a hump in the free energy curve of L in a eutectic alloy --- p.2 / Chapter 1.3 --- Spinodal decomposition --- p.2 / Chapter 1.4 --- Early experience --- p.3 / Chapter 1.5 --- Bulk metallic glasses (BMG) --- p.5 / Chapter 1.6 --- Metal matrix composites (MMC) --- p.6 / Chapter 1.7 --- Liquid state phase separation and the formation of metal matrix comosites by fluxing --- p.6 / Chapter Chapter2 --- Experimental --- p.15 / Chapter 2.1 --- Introduction --- p.15 / Chapter 2.2 --- Preparation of fused silica tube --- p.15 / Chapter 2.3 --- Sample Preparation --- p.16 / Chapter 2.3.1 --- Alloying --- p.16 / Chapter 2.3.2 --- Fluxing --- p.16 / Chapter 2.4 --- Liquidus of Fe-C-Si specimens --- p.16 / Chapter 2.5 --- Microstructure Analysis --- p.17 / Chapter 2.6 --- Mechanical properties --- p.18 / Chapter 2.6.1 --- Hardness test --- p.18 / Chapter 2.6.2 --- Compressive strength --- p.18 / Chapter Chapter3 --- Formation and mechanical properties of Fe86Si14 network alloys --- p.23 / Chapter 3.1 --- Abstract --- p.23 / Chapter 3.2 --- Introduction --- p.24 / Chapter 3.3 --- Experimental --- p.25 / Chapter 3.4 --- Results --- p.27 / Chapter 3.5 --- Discussion --- p.33 / Chapter Chapter4 --- Dependence of mechanical behavior on C concentration in Fe-C-Si network alloys --- p.63 / Chapter 4.1 --- Abstract --- p.63 / Chapter 4.2 --- Introduction --- p.64 / Chapter 4.3 --- Experimental --- p.66 / Chapter 4.4 --- Results --- p.68 / Chapter 4.5 --- Discussions --- p.76
124

Mechanism of the reaction catalyzed by the oxalate decarboxylase from Bacillus subtilis

Svedružić, Draženka. January 2005 (has links)
Thesis (Ph.D.)--University of Florida, 2005. / Title from title page of source document. Document formatted into pages; contains 122 pages. Includes vita. Includes bibliographical references.
125

Formation and dissociation reaction rates and relevant kinetic behavior of propane gas hydrate (PGH)

Song, Feng. January 2001 (has links)
Thesis (M.S.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains xi, 59 p. : ill. Includes abstract. Includes bibliographical references (p. 57-59).
126

The Rate inhibiting effect of water as a product on reactions catalysed by cation exchange resins formation of mesityl oxide from acetone as a case study /

Du Toit, Elizabeth Louisa. January 2003 (has links)
Thesis (M. Sc.)(Chemical Eng.)--University of Pretoria, 2003. / Bibliography included.
127

Influence of the nephelauxetic effect on the kinetic and thermodynamic stability of cobalt (III) complexes of the tetramine type.

Tong, Ha-wai. January 1973 (has links)
Thesis Ph. D., University of Hong Kong. / Includes reprints of 2 papers entitled Structural and mechanistic studies of co-ordination compounds. Part II ... by C.K. Poon and H.W. Tong, from the Journal of the Chemical Society (A), 1971, and Structural and mechanistic studies of co-ordination compounds. Part V ... by K.S. Mok and others, from the Journal of the Chemical Society (Dalton), 1972.
128

Spectral and kinetic studies of some octahedral cobalt (III) complexes.

Lee, Chi-kin. January 1973 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1973. / Typewritten.
129

The kinetics and mechanism of substitution in some cobalt (III) complexes.

Leung, Ping-yuen. January 1969 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1970. / Typewritten.
130

Substitutions of four-coordinated complexes.

Wong, Fai-tai. January 1969 (has links)
Thesis (Ph. D.)--University of Hong Kong. / Typewritten.

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