Over the past decades, since the discovery of a single–site silica-supported catalyst for the alkane metathesis reaction by our group, we have been extensively working on the development of supported catalytic systems for the improved alkane metathesis reaction. During these developments, we understand the reaction mechanism and reached a new perspective for the synthesis of various supported bimetallic systems via the surface organometallic chemistry (SOMC) approach. Recently, with this bi-metallic system, we got a very high TON (10000) in propane metathesis reaction. As these catalysts are very efficient for linear alkanes we thought to apply it for cyclo-alkanes specifically, for cyclo-octane metathesis expecting better activity. Besides, the value of the ring alkanes are higher than the linear alkanes. The current work demonstrates a combination of [(ΞSi−O−)W(Me)5] and [(ΞSi− O−)Ti(Np)3 pre-catalyst with several supports (SiO2-700, SBA-15 and MCM-41) for metathesis of cyclooctane. The catalysts have been synthesized and fully characterized by elemental analysis (EA), FT-IR and NMR spectroscopies. After fully characterization the bi-metallic catalyst was tested for metathesis of cyclooctane with highest ever TON 2500 as compared to that of mono-metallic catalyst where we got 430 TON. Which again corroborates our prediction that bimetallic catalysts are better catalysts than monometallic catalysts.

Chau, Chun Pong. / "August 2010." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 67-71). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Motivation --- p.1 / Chapter 1.2 --- Objectives --- p.4 / Chapter 1.3 --- Contribution --- p.4 / Chapter 1.4 --- Thesis Organization --- p.5 / Chapter 2 --- Background and Review --- p.6 / Chapter 2.1 --- Introduction --- p.6 / Chapter 2.2 --- Logic Cell Style and Mask Programmability --- p.6 / Chapter 2.3 --- CAD Tools Compatibility --- p.8 / Chapter 2.4 --- Summary --- p.9 / Chapter 3 --- Architectural Design --- p.11 / Chapter 3.1 --- Overview --- p.11 / Chapter 3.2 --- Programmable Layers --- p.12 / Chapter 3.3 --- Combinational Logics --- p.12 / Chapter 3.4 --- Sequential Logics --- p.19 / Chapter 3.5 --- Inter-cell Connections --- p.21 / Chapter 3.6 --- Hard Macros --- p.22 / Chapter 3.7 --- Summary --- p.22 / Chapter 4 --- Design Flow --- p.23 / Chapter 4.1 --- Overview --- p.23 / Chapter 4.2 --- Library Creation --- p.24 / Chapter 4.3 --- Synthesis --- p.30 / Chapter 4.4 --- Placement and Routing --- p.30 / Chapter 4.5 --- Static Timing Analysis --- p.34 / Chapter 4.6 --- Summary --- p.35 / Chapter 5 --- Experimental Results --- p.36 / Chapter 5.1 --- Benchmark Circuits Description --- p.36 / Chapter 5.2 --- Experiment Settings --- p.37 / Chapter 5.3 --- Ratio of Dedicated Elements --- p.42 / Chapter 5.4 --- Delay and Area Comparison --- p.49 / Chapter 5.5 --- Distributed Memories --- p.53 / Chapter 5.6 --- Summary --- p.54 / Chapter 6 --- Prototypes and Applications --- p.55 / Chapter 6.1 --- Overview --- p.55 / Chapter 6.2 --- First Prototype --- p.55 / Chapter 6.3 --- Second Prototype --- p.63 / Chapter 7 --- Conclusion --- p.65 / Chapter 7.1 --- Future Work --- p.66 / Chapter 7.2 --- Concluding Remark --- p.67

Ho, Yuk Ting. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references. / Abstracts in English and Chinese. / Acknowledgement --- p.i / Abstract --- p.vi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Composite Materials --- p.1 / Chapter 1.2 --- General Properties of Composite Materials --- p.2 / Chapter 1.3 --- Fabrication of Composite Materials --- p.3 / Chapter 1.3.1 --- Liquid State Sintering --- p.4 / Chapter 1.3.2 --- Casting --- p.6 / Chapter 1.3.3 --- Other Fabrication Techniques --- p.7 / Chapter 1.4 --- Phase Transformation --- p.8 / Chapter 1.5 --- Nucleation and Growth --- p.10 / Chapter 1.5.1 --- Homogeneous nucleation --- p.10 / Chapter 1.5.2 --- Heterogeneous nucleation --- p.10 / Chapter 1.5.3 --- Growth --- p.11 / Chapter 1.6 --- Phase Separation by Spinodal Decomposition --- p.11 / Chapter 1.6.1 --- The Initiation of Spinodal Decomposition --- p.12 / Chapter 1.6.2 --- Dynamics of Spinodal Decomposition --- p.12 / Chapter 1.6.3 --- Difference between Coherent Spinodal and Nucleation and Growth --- p.17 / Chapter 1.7 --- Methods in Obtaining Large Under-cooling --- p.19 / References --- p.20 / Figures --- p.23 / Chapter Chapter 2 --- Experiment --- p.29 / Chapter 2.1 --- Introduction --- p.29 / Chapter 2.2 --- Preparation of Fused Silica Tubes --- p.29 / Chapter 2.3 --- Sample Preparation --- p.30 / Chapter 2.3.1 --- Alloying --- p.30 / Chapter 2.3.2 --- Fluxing --- p.30 / Chapter 2.3.3 --- Under-cooling --- p.31 / Chapter 2.4 --- Microstructure Analysis --- p.32 / Chapter 2.4.1 --- Sample Surface Analysis --- p.32 / Chapter 2.4.2 --- Scanning Electron Microscopy (SEM) --- p.32 / Chapter 2.5 --- Transmission Electron Microscopy (TEM) --- p.32 / Chapter 2.5.1 --- Specimen Requirement --- p.33 / Chapter 2.5.2 --- "Cutting, Grinding, Polishing and Pouching" --- p.33 / Chapter 2.5.3 --- Dimpling --- p.34 / Chapter 2.5.4 --- Ion Milling --- p.34 / Chapter 2.5.5 --- Microstructure Characterization by TEM --- p.35 / Chapter 2.6 --- Mechanical Properties --- p.37 / Chapter 2.6.1 --- Hardness Testing --- p.37 / Chapter 2.6.2 --- Compression Testing --- p.37 / Chapter 2.7 --- Characterizations of Untreated Samples --- p.38 / References --- p.39 / Figures --- p.40 / Chapter Chapter 3 --- Formation and Properties of Co-Si-B Metal Matrix Composites --- p.44 / Abstract --- p.44 / Introduction --- p.45 / Experimental --- p.46 / Results --- p.47 / Chapter A. --- Microstructures --- p.48 / Eutectic Co75Si15B10 --- p.48 / Network Co75Si15B10 --- p.48 / Chapter B. --- Mechanical Behavior --- p.50 / Eutectic Co75Si15B10 --- p.50 / Network CO75Si15B10 --- p.51 / Discussions --- p.53 / Conclusion --- p.53 / Acknowledgement --- p.54 / References --- p.55 / Figures --- p.56 / Chapter Chapter 4 --- On the Network Morphology of Co75Si15B10 Alloys --- p.68 / Abstract --- p.68 / Introduction --- p.69 / Experimental --- p.69 / Results --- p.69 / Discussions --- p.74 / Acknowledgement --- p.77 / References --- p.78 / Figures --- p.79 / Chapter Chapter 5 --- Conclusion --- p.100

Chung, Kam Chuen = 鐵基/鐵三鋁基/鋁基金屬基複合材料的合成和表徵 / 鍾錦銓. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / Chung, Kam Chuen = Tie ji/tie san lü ji/lü ji jin shu ji fu he cai liao de he cheng he biao zheng / Zhong Jinquan. / Abstract --- p.i / 摘要 --- p.iii / Acknowledgement --- p.v / Table of contents --- p.vi / List of tables --- p.x / List of figures --- p.xi / Chapter Chapter 1 --- Introduction --- p.1-1 / Chapter 1.1. --- Metal matrix composites (MMCs) --- p.1-1 / Chapter 1.1.1. --- Introduction --- p.1-1 / Chapter 1.1.2. --- Matrix materials --- p.1-1 / Chapter 1.1.3. --- Reinforcements --- p.1-2 / Chapter 1.1.4. --- Fabrication techniques --- p.1-3 / Chapter 1.1.5. --- Applications --- p.1-7 / Chapter 1.2. --- MMCs in this work --- p.1-9 / Chapter 1.2.1. --- Metal matrices --- p.1-9 / Chapter 1.2.2. --- Reinforcements --- p.1-11 / Chapter 1.3. --- Previous works --- p.1-13 / Chapter 1.4. --- Objectives and current works --- p.1-15 / Chapter 1.5. --- Thesis layout --- p.1-16 / References --- p.1-18 / Chapter Chapter 2 --- Methodology and Instrumentation --- p.2-1 / Chapter 2.1. --- Powder metallurgy (PM) --- p.2-1 / Chapter 2.1.1. --- Mixing --- p.2-1 / Chapter 2.1.2. --- Compacting --- p.2-1 / Chapter 2.1.3. --- Sintering --- p.2-2 / Chapter 2.2. --- Sample preparation --- p.2-3 / Chapter 2.2.1. --- Mixing and compacting --- p.2-3 / Chapter 2.2.2. --- Tube furnace sintering --- p.2-3 / Chapter 2.2.3. --- Arc melting --- p.2-4 / Chapter 2.3. --- Sample characterization --- p.2-4 / Chapter 2.3.1. --- DTA and DSC --- p.2-5 / Chapter 2.3.2. --- XRD --- p.2-6 / Chapter 2.3.3. --- SEM --- p.2-6 / Chapter 2.3.4. --- TEM --- p.2-6 / Chapter 2.3.5. --- Microhardness test --- p.2-7 / Chapter 2.3.6. --- VSM --- p.2-7 / References --- p.2-9 / Chapter Chapter 3 --- Synthesis of magnetic hercynite in Fe-based MMC --- p.3-1 / Chapter 3.1. --- Introduction --- p.3-1 / Chapter 3.2. --- Experiments --- p.3-2 / Chapter 3.3. --- Results and discussion --- p.3-2 / Chapter 3.3.1. --- DTA and XRD results --- p.3-2 / Chapter 3.2.2. --- SEM and EDS results --- p.3-3 / Chapter 3.3.3. --- Reaction mechanisms --- p.3-5 / Chapter 3.3.4. --- Thermodynamic model for the reactions --- p.3-8 / Chapter 3.3.5. --- Saturation magnetization --- p.3-9 / Chapter 3.3.6. --- Microhardness --- p.3-11 / Chapter 3.4. --- Conclusions --- p.3-11 / References --- p.3-13 / Chapter Chapter 4 --- Synthesis of reinforced Fe3Al-based MMC --- p.4-1 / Chapter 4.1. --- Introduction --- p.4-1 / Chapter 4.2. --- Experiments --- p.4-2 / Chapter 4.3. --- Results and discussion --- p.4-4 / Chapter 4.3.1. --- AI2O3-reinforced samples --- p.4-4 / Chapter 4.3.2. --- MgO-reinforced samples --- p.4-8 / Chapter 4.3.3. --- MgAl204-reinforced samples --- p.4-11 / Chapter 4.3.4. --- Microhardness and densities --- p.4-14 / Chapter 4.4. --- Conclusions --- p.4-16 / References --- p.4-18 / Chapter Chapter 5 --- Formation of Al-Fe intermetallics in Al-based MMC…… --- p.5-1 / Chapter 5.1. --- Introduction --- p.5-1 / Chapter 5.2. --- Experiments --- p.5-2 / Chapter 5.3. --- Results and discussion --- p.5-3 / Chapter 5.3.1. --- DTA and XRD results --- p.5-3 / Chapter 5.2.2. --- "SEM, TEM and EDS results" --- p.5-4 / Chapter 5.3.3. --- Reaction mechanisms --- p.5-9 / Chapter 5.3.4. --- Phase transformation in solidification --- p.5-11 / Chapter 5.3.5. --- Microhardness --- p.5-13 / Chapter 5.4. --- Conclusions --- p.5-14 / References --- p.5-15 / Chapter Chapter 6 --- Conclusions and future work --- p.6-1 / Chapter 6.1. --- Conclusions --- p.6-1 / Chapter 6.2. --- Future work --- p.6-3

No presente trabalho foram realizados estudos da atividade biológica de complexos imínicos de Cu(II) e Zn(II) derivados da isatina, principalmente frente a células tumorais HeLa. Sabe-se que estes complexos se ligam ao DNA, podendo causar clivagens simples e duplas na sua estrutura, em presença de peróxido de hidrogênio, através de um mecanismo predominantemente oxidativo. Os complexos de Cu(II) geram espécies reativas de oxigênio (EROs) e, além disto, atuam sobre a mitocôndria como agentes desacopladores. Sabe-se ainda que esses compostos interagem com proteínas específicas, como por exemplo a topoisomerase humana IB e as quinases dependentes de ciclinas (CDKs), inibindo significativamente sua atividade, ou a proteassoma, frente à qual apenas uma inibição moderada foi observada. Os ensaios in vitro desenvolvidos nesta tese, permitiram evidenciar a capacidade de os complexos de intercalar no DNA e RNA, além de clivar o primeiro biopolímero. Os resultados obtidos in celullo, evidenciaram a dependência do cobre para a citotoxicidade dos complexos sendo estes compostos capazes de estimular a necrose das células HeLa. Além disso, os resultados demonstraram que estes compostos são capazes de interferir no ciclo celular, interrompendo-o em fase G2/M e de desencadear um desequilíbrio oxidativo. Os principais alvos intracelulares dos complexos, em células HeLa, são a Mitocôndria, pois interferem em seu funcionamento diminuindo o seu potencial de membrana, e o DNA clivando-o. Ademais, pretendeu-se, através de um estudo sistemático por microscopia Raman confocal, identificar danos celulares provocados pelos complexos, especialmente uma grande alteração no núcleo celular de células HeLa após o tratamento com o complexo [Cu(isaepy)]+. Através de ensaios de viabilidade, também foi possível demonstrar que a superexpressão de glicoproteína-P para linhagem MES-AS/Dx5 não resulta na resistência dessas células frente aos compostos testados, e que os complexos não interferem no funcionamento desta glicoproteína. Também foi observado, através dos experimentos com células HaCaT, que o complexo [Zn(isaepy)]2+ é capaz de interferir no ciclo autofágico celular. / In the present work, the synthesis and characterization of oxindolimine complexes of Cu(II) and Zn(II) were carried out. R is known that these complexes bind to DNA and can cause single and double cleavages in their structure, in the presence or absence of hydrogen peroxide, through a predominantly oxidative mechanism. Cu(II) complexes generate reactive oxygen species (ROS) and, in addition, act on mitochondria as decoupling agents. These compounds are also known to interact with specific proteins, such as human topoisomerase IB and cyclin-dependent kinases (CDKs), inhibiting significantly their activity, or the proteasome, against which only moderate inhibition has been observed. The in vitro assays developed in this thesis have demonstrated the ability of these complexes in intercalating at DNA and RNA, in addition to cleaving the first biopolymer. The results in cellulo evidenced the dependence on the copper for the cytotoxicity of the complexes, that can stimulate the necrosis in HeLa cells. In addition, the results demonstrated that these compounds are capable of interfering in the cell cycle, stopping it at G2/M phase and triggering an oxidative imbalance. The main intracellular targets of the complexes, in HeLa cells, are the Mitochondria, where they interfere in its function, diminishing its membrane potential, and the DNA, causing its cleavage. Further, it was intended, through a systematic study by confocal Raman microscopy, to identify cellular damage triggered by the complexes. Particularly, a large change in the cell nucleus of HeLa cells was demonstrated after treatment with the \'[Cu(isaepy)] POT.+\' complex. Through viability assays, it was also demonstrated that overexpression of P-glycoprotein in MES-SA/Dx5 lineage does not result in the resistance of these cells to the tested compounds, and that the complexes do not interfere in the functioning of this glycoprotein. Finally, it was observed, in experiments with HaCaT cells, that \'[Zn(isaepy)] POT.2+\' complex can interfere in the autophagic cell cycle.

Metallic glass matrix composites have enormous potential stemming from the interplay between crystalline and amorphous phases. This work models such a composite using shear transformation zone dynamics (a modified kinetic Monte Carlo method) for the amorphous phase, and a local Taylor dislocation model for the crystalline phase. An N-factorial experiment using the model is presented examining the effects of crystalline volume fraction, microstructure length scale, and yield stress of the crystalline phase. Each replicate is analyzed for maximum stress, maximum strain, strain energy dissipation, strain localization, and strain partitioning between phases. Regression analysis is used to identify statistically-significant trends in the data. The experiment shows that strain delocalization and the consequent ductility are facilitated by a crystalline phase with a substantially lower yield stress than that of the amorphous matrix. It also shows that increasing crystalline volume fraction alone is insufficient to promote strain delocalization in the case of a crystalline phase with high relative yield stress, and that a lower yield stress for the crystalline phase implies lower maximum stresses supported by the composite. Therefore designers must balance the need for ductility and delocalization against the composite yield stress by finding an optimal combination of volume fraction and crystalline mechanical properties. This work provides continuous functional forms for the relationships between these properties to aid in that optimization process.

La motivation principale de cette thèse est d’être capable de prédire précisément la rupture d’une tôle d’aluminium anisotrope avec un chemin de déformation linéaire et non-linéaire. Dans le cas présent, le matériau utilisé est l’AA6016 et le chemin de déformation considéré est traction uniaxiale suivie de pliage jusqu’à rupture. Deux approches sont appliquées et comparées, l’une utilise la plasticité associée (AFR) et l’autre la plasticité non-associée (NAFR). Dans le but d’obtenir une bonne représentation de l’anisotropie en AFR, un critère de plasticité très flexible est utilisé : Yld2004-18p. L’identification des paramètres est faite avec une approche inverse qui consiste à minimiser itérativement l’écart entre les résultats numériques et expérimentaux. Une fois que l’écart arrête d’évoluer (minimum local) ou atteint une valeur prédéterminé e assez faible, l’optimisation s’arrête et les derniers paramètres mis à jour sont enregistrés. En corrélation avec des travaux de recherche plus récents, un modèle NAFR est utilisé pour modéliser l’anisotropie du matériau. Il combine deux critères de plasticité qui sont utilisés pour la surface d’écrouissage et le potentiel plastique. Leurs paramètres sont identifiés grâce aux ratios de contraintes et aux valeurs r obtenues expérimentalement. Concernant la rupture, des modèles découplés macroscopiques sont étudiés : un critère Hosford-Coulomb modifié et un critère basé sur DF2014. Ces deux critères prennent en compte les trois invariants du tenseur des contraintes pour prédire la déformation équivalente à rupture mais sont identifiés avec différentes méthodes pour prendre en compte l’anisotropie de la rupture. Enfin, des résultats sur des instabilités plastiques obtenus avec un modèle NAFR sont présentés dans le but de prouver les possibilités de cette approche comparée à une approche AFR. / The main motivation of this thesis is to be able to predict accurately the fracture of an anisotropic aluminium alloy thin sheet under linear and non-linear strain paths. In the studied case, the material used is the AA6016 and the non-linear strain path considered is uniaxial tension followed by free bending until fracture. Two approaches are considered and compared which respectively use the associated flow rule (AFR) and the non-associated flow rule (NAFR). In order to obtain a good representation of the high anisotropy of the material in AFR, a very flexible yield criterion is used: Yld2004-18p. The identification of its parameters is done with an inverse approach consisting of iteratively minimizing the gap between numerical and experimental results. Once this gap stops evolving (local minimum) or reaches a low enough pre-determined value, the optimization stops and the last updated parameters are saved. In correlation with more recent research work, a NAFR model is used to model the anisotropy of the material. It combines two different yield functions that are used for the yield surface and the plastic potential. Their parameters are identified by using stress ratios and rvalues measured experimentally. Concerning the fracture, uncoupled macroscopic models are studied: a modified Hosford-Coulomb and a DF2014 based criteria. Both these criteria take into account the three invariants of the stress tensor to predict the equivalent strain to fracture but their parameters are identified with different methods to take into account the anisotropy of the fracture. Finally, results on plastic instabilities obtained with a NAFR model are presented in order to prove the possibilities of this approach compared to AFR.

<p>The main part of this work has been a literature survey, reviewing scientifical reports forinformation on how steel cleanness is evaluated today, and also how the steel cleanness is related tothe fatigue performance of clean steels.</p>

A high temperature high vacuum rheometer has been designed, fabricated, and tested for the study of the steady shear viscosity for multicomponent bulk metallic glass forming alloys. This rheometer has an operating range up to 1525 K, rotational frequencies of 9.4*10⁻³-3.7*10¹ radians/s, and a calibrated viscosity range of 9.6*10⁻³ and 1.2*10² Pa*s while maintaining absolute pressures pressure < 1*10⁻⁶ mbar. Zr[subscript 41.2]Ti[subscript 13.8]Cu[subscript 10.0]Ni[subscript 12.5]Be[subscript 22.5] (Vitreloy 1) is reported. The unexpected findings of non-Newtonian behavior above the liquidus temperature were observed. Observations of shear thinning, thixotropic, and viscoelastic behaviors have been made. Our results show that Vitreloy 1 can be modeled as a power law fluid, with a power law exponent of approximately -0.5 for high shear rates. We attribute the non-Newtonian behavior to structural ordering within the melt. The technological and scientific implications for non-Newtonian behavior are discussed. / Graduation date: 2005

The microstructure, and phase selections of La₆₆Al₁₄(Cu, Ni)₂₀ alloy were studied by Bridgman solidifications, and composite materials of dendrites in amorphous matrix or micro- and nano- sized eutectic matrix were formed with different cooling rates. The volume fraction of the dendrite phase reaches a maximum at the cooling rate of about 15 K/s, the secondary dendrite arm spacing λ₂ decreases from 4.3 µm to 0.6 µm with the increasing of cooling rate R, and obeys the equation of λ₂R⁰.⁵&#x2077=1.74µm(K/s)R⁰.⁵&#x2077. The compression strength, as well as the elastic strain limit of the dendrite/amorphous matrix composite are 600 MPa, and 2.3%, respectively. Improved ductility was observed for the dendrite amorphous matrix composites with more dendrite phase by slow cooling rate. / Singapore-MIT Alliance (SMA)