This thesis describes studies directed to the ring opening metathesis polymerisation of macromonomers and mesogenic monomers to produce graft copolymers and side chain liquid crystalline polymers respectively. The necessary background information relevant to the work described in this thesis is presented in chapter-1 and consists of four sections; namely, descriptions of metathesis polymerisation, anionic polymerisation, synthesis of graft copolymers and synthesis of side chain liquid crystalline polymers. The synthesis of the end capping reagent exo-5-norbomene-2- carbonyl chloride is described in chapter-2. The synthesis and characterisation of exo- 5-norbomene-2-poly(styrylcarboxylate) macromonomers by living anionic polymerisation is discussed in chapter-3. Chapter-4 reports the synthesis, characterisation and properties of graft copolymers prepared by ring opening metathesis polymerisation of exo-5-norbomene-2-poly(styrylcarboxylate) macromonomers. Chapters-5 describes the synthesis of the mesogenic monomer; (5)- (-)-2-methylbutyl-4-(4-(l 0-(3-cyclopentenylmethoxy) decyloxy) phenylcarbonyloxy) benzoate, suitable for ring opening metathesis polymerisation to produce side chain liquid crystalline polymer. The attempted synthesis of side chain liquid crystalline polymer by ring opening metathesis polymerisation of the mesogenic monomer; (5)-(- )-2-methylbutyl-4-(4-( 10-(3 -cyclopentenylmethoxy) decyloxy) phenylcarbonyloxy) benzoate is reported in chapter-6. Finally chapter-7 summarises the conclusions and makes some suggestions for future work.

This thesis describes experiments carried out on two novel strongly correlated electron systems. The first, FeCrAs, is a new material that has not been studied before, while the second, Sr3Ru2O7, has been previously shown to have a very novel so-called ‘nematic’ phase around the metamagnetic quantum critical end point (QCEP). For these studies, a new variation on an established method for measuring the field dependence of susceptibility in a BeCu clamp cell has been developed, and is described, as is a relaxation heat capacity cell that works from 4 K down to 300 mK. A method of growing stoichiometric crystals of the hexagonal iron-pnictide FeCrAs has been developed, and transport and thermodynamic measurements carried out. The in-plane resistivity shows an unusual “non-metallic” dependence on temperature T, rising continuously with decreasing T from ∼800 K to below 100 mK. The c-axis resistivity is similar, except for a sharp drop upon entry into an antiferromagnetic state at T_N ∼ 125 K. Below 10 K the resistivity follows a non-Fermi-liquid power law, ρ(T) = ρ_0 − AT^x with x < 1, while the specific heat shows Fermi liquid behaviour with a large Sommerfeld coefficient, γ ∼ 30 mJ/molK^2. The high temperature properties are reminiscent of those of the parent compounds of the new layered iron-pnictide superconductors, however the T → 0 K properties suggest a new class of non-Fermi liquid. The metamagnetic critical end point temperature T^∗ in Sr3Ru2O7 as a function of hydrostatic pressure with H//ab has been studied using the ac susceptibility. It is found that T^∗ falls monotonically with increasing pressure, going to zero at Pc = 14±0.3 kbar. One sign of the nematic phase observed in the field-angle tuning, i.e. T^∗ rises as the novel phase emerges, has not been seen in our study. However, we see a slope change in T^∗ vs P at ∼12.8 kbar, and a shoulder at the upper field side of the peak in χ′ from ∼12.8 kbar to ∼16.7 kbar. These new features indicate that some new physics sets in near the pressure-tuned QCEP.

No description available.

objective of this thesis is to contribute to the understanding of the behavior of the liquid metal eutectic gallium/indium (EGaIn) in composite systems and provide a platform for the development of functional hybrid nanocomposites. Contributions are regarding (i) the investigation of the electromechanical coupling performance of EGaIn as electrodes in a soft electrostatic transducer and (ii) the effectiveness of organic surfactants to stabilize EGaIn nanoparticles in organic solvents. For the first portion, a completely soft dielectric elastomer actuator (DEA) using EGaIn electrodes was fabricated and evaluated. Experimental actuation of the DEA showed high agreement with a generalized NeoHookean constitutive law, assuming uniaxial pre-stretch and considering the device saddle deformation. The expected conductive behavior of the liquid alloy was confirmed, and further efforts have focused on the development and stabilization of EGaIn nanodroplets, which do not exhibit the problems associated with larger pools of EGaIn (such as leakage) and can be applied to soft multifunctional materials. A computational procedure was developed for calculating suspended EGaIn nanoparticle mass in order to determine reaction yields using applied Mie theory and optical characterization techniques (dynamic light scattering and UV/Vis spectrophotometry). This method calculated total mass to within 20% when applied to a known system. A systematic study evaluating particle yield as a function of aliphatic surfactant composition and concentration (and solvent type) revealed a pronounced dependence of nanodroplet formation on the solvent type as well as surfactant structure. Ethanol (EtOH) was found to be the most effective solvent for the formation and stabilization of EGaIn nanodroplets, in which only thiol-based surfactants were found to improve nanodroplet yield. Results suggest a stabilization mechanism other than the expected self-assembled monolayer (SAM) formation. The research has been extended to alternative (e.g. plant based) surfactant systems.

M.Phil. (Energy Studies) / Liquid fuels provide in a large percentage of South Africa's energy requirements. Because of the vastness of the country no other means of propelling transport could take the place of liquid fuel. South Africa who has for a substantial period found herself being officially cut-off from international crude oil (embargo) and other commodities such as capital, had up to ± 1991 survive this onslaught. Alternatives for the substitution of crude oil derived products (mostly liquid fuels) has been under investigation for many years, internationally as well as locally~ Because of the recent change in the situation, the approach to new investment in this field will now only be effected should it be economically more attractive than investment in the traditional crude oil processes. This study was specifically aimed at, from a South African viewpoint, summarizing various applicable liquid fuel manufacturing processes and related raw material resources, and comparing these processes both from an economic and technological angle with that of crude oil refining. The following resources were investigated: Coal, torbanite, sugar (from sugar cane), natural gas and sunflower seeds. Processes such as coal to fuels (Fischer-Tropsch, coal hydrogenation, solvent extraction), metanol to fuels (MTG-process), metanol ex natural gas (Mobil-M), methanol ex coal, ethanol ex sugar, natural gas to fuels (Fischer-Tropsch, Shell-SMOS), esters (diesel) ex sunflower seeds, fuels ex torbanite via retorting were researched. Aspects covering the availability of resources, degree of commercialisation of processes, product quality and fuel/engine compatibility and general economic and technological guidelines were covered in the study.

Thesis advisor: Kevin S. Bedell / In 1956, Lev Davidovich Landau put forth his theory on systems of interacting fermions, or fermi liquids. A year later, Viktor Pavlovich Silin described spin waves that such a system of fermions would support. The treatment of the contribution of the molecular field to the spin wave dispersion was a novel aspect of these spin waves. Silin predicted that there would exist a hierarchy of spin waves in a fermi liquid, one for each component of the spherical harmonic expansion of the fermi surface. In 1968, Anthony J. Leggett and Michael J. Rice derived from fermi liquid theory how the behavior of the spin diffusion coefficient of a fermi liquid could be directly experimentally observable via the spin echo effect. Their prediction, that the diffusion coefficient of a fermi liquid would not decay exponentially with temperature, but rather would have a maximum at some non-zero temperature, was a direct consequence of the fermi liquid molecular field and spin wave phenomena, and this was corroborated by experiment in 1971 by Corruccini, et al. A parallel advancement in the theory of fermi liquid spin waves came with the extension of the theory to describe weak ferromagnetic metals. In 1959, Alexei Abrikosov and I. E. Dzyaloshiski put forth a theoretical description of a ferromagnetic fermi liquid. In 2001, Kevin Bedell and Krastan Blagoev showed that a non-trivial contribution to the dispersion of the ferromagnetic current spin wave arises from the necessary consideration of higher harmonic moments in the distortion of the fermi surface from its ground state. In the chapters to follow, the author presents new results for transverse spin waves in a fermi liquid, which arise from a novel ground state of a fermi liquid--one in which an l=1 harmonic distortion exists in the ground state polarization. It is shown that such an instability can lead to spin waves with dispersions that are characterized by a linear dependence on the wave number at long wavelengths, or can lead to spin waves that are characterized by a square root dependence on the wave number at long wavelength. The author also presents new results for spin waves in a fermi liquid that has a spin density wave in its ground state. A spin density wave is characterized by a spiral magnetization in the ground state, and is observed to occur in materials such as MnSi. / Thesis (PhD) — Boston College, 2009. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Physics.

by Wai Ming Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 71-74). / ACKNOWLEDGEMENTS --- p.i / CONTENTS --- p.ii / ABSTRACT --- p.iv / Chapter I. --- INTRODUCTION --- p.1 / Chapter I-1. --- Liquid Crystal Mesophases --- p.1 / Chapter I-1-1. --- Mesophases --- p.1 / Chapter I-1 -2. --- Classification of liquid crystals according to molecular order --- p.1 / Chapter I-2. --- Ferroelectric Liquid Crystals --- p.6 / Chapter I-3. --- "The Relationship Among Spontaneous Polarization, Tilted Angle and Response Time" --- p.7 / Chapter I-4. --- Applications of Liquid Crystals --- p.8 / Chapter I-5. --- An Ideal Ferroelectric Liquid Crystal --- p.9 / Chapter I-6. --- Recent Development in Chiral Liquid Crystals --- p.10 / Chapter I-7. --- Aim of The Present Research: Chiral Liquid Crystals from Carbohydrates --- p.15 / Chapter II. --- RESULTS AND DISCUSSION --- p.17 / Chapter II-1. --- "Synthesis of 4',4""-Heptoxybiphenyl (methyl 2-O-n- butyl-3,4-dideoxy-a-D-glucopyranosid) uronate (12) and 4',4""-Cyanobiphenyl (methyl 2-O-n-butyl -3,4-dideoxy-a-D-glucopyranosid) uronate (13)" --- p.17 / Chapter II-2. --- "Synthesis of 4',4''-Heptoxybiphenyl (methyl 2-O-n- butyl-3,4-di-O-methyl-a-D-glucopyranosid) uronate (14) and 4' ,4""-Cyanobiphenyl (methyl 2-O-n-butyl -3,4-di-O-methyl-α-D-glucopyranosid) uronate (15)" --- p.33 / Chapter II-3. --- Mesomorphic Phases and Transition Temperatures of Chiral Liquid Crystalline Compounds 12 and 13 --- p.42 / Chapter III. --- CONCLUSION --- p.47 / Chapter IV. --- EXPERIMENTAL SECTION --- p.48 / Chapter V. --- REFERENCES --- p.71 / List of Spectra --- p.75 / Spectra --- p.76

by Qian Wang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 107-111). / Acknowledgements --- p.i / Contents --- p.ii / Abstract --- p.iv / Chapter I. --- Introduction --- p.1 / Chapter II. --- Results and Discussion --- p.23 / Chapter II-1. --- "Stereoselective Synthesis of Chiral Liquid Crystalline Compounds Containing a 1,4-Disubstituted Cyclohexene Ring" --- p.23 / Chapter II-1-1. --- "Synthesis of (S)-(-)- and (R)-(+)-4'-(4""-Cyanobiphenyl) 4-Pentyl-3-cyclohexene-1-carboxylate (1 and 3) and (S)-(-)-4'-(4""-Octoxybiphenyl) 4-Pentyl-3-cyclohexene-1-carboxylate (2)" --- p.23 / Chapter II-1-2. --- "Synthesis of (S)-(-)-4'-(4""-Cyanobiphenyl) 4-Butoxymethyl-3-cyclohexene-1-carboxylate (4)" --- p.35 / Chapter II-1-3. --- "Synthesis of (S)-(-)- and (R)-(+)-4'-(4""-Heptoxybiphenyl) 4-(2-Propenyl)-1-cyclohexene-1-carboxylate (5 and 7) and (S)-(-)- and (R)-(+)-4'-(4""-Octoxybiphenyl) 4-(2-Propenyl)-1-cyclohexene-1-carboxylate (6 and 8)" --- p.37 / Chapter II-2. --- "Synthesis of Chiral Liquid Crystalline Compound Containing a trans-2,5-Disusbstituted Cyclohexanone Ring´ؤ(1S,4S)-4'-(4""-Heptoxybiphenyl) 4-Penyl-3-cyclohexanone-1-carboxylate (9)" --- p.42 / Chapter II-3. --- "Determination of Enantiomeric Purities of (S)-(-)- and (R)-(+)-Perillalcohols (17 and 28), (S)-(-)- and (R)-(+)-1-Pentyl-4-hydroxymethyl-l-cyclohexenes(35 and 36), and (2S,5S)-2-Pentyl-5-hydroxymethyl-l-cyclohexanone (64)" --- p.58 / Chapter II-3-1. --- Determination of Enantiomeric Purities of (S)-(-)- and (R)-(+)-Perillalcohols (17 and 28) --- p.58 / Chapter II-3-2. --- Determination of Enantiomeric Purities of (S)-(-)- and (R)-(+)-1-Pentyl-4-hydroxymethyl-1-cyclohexenes (35 and36) --- p.64 / Chapter II-3-3. --- "Determination of Enantiomeric Purity of (2S,5S)-2-Pentyl-5-hydroxymethyl-1 -cyclohexanone (64)." --- p.67 / Chapter II-4. --- "Mesomorphic Phases and Transition Temperatures of Chiral Liquid Crystalline Compounds 2, 3, 5, 6, 7, 8 and 9" --- p.72 / Chapter III. --- Conclusion --- p.77 / Chapter IV. --- Experimental --- p.78 / Chapter V. --- References --- p.107 / List of Spectra --- p.112 / Spectra --- p.116

"Composites of nanoparticles with complex fluids represent a unique physical system where thermal physical properties of the components partially or fully mix and new behavior can emerge. Traditional composites are relatively well understood as the superposition, weighted by volume or mass, of the components properties and the interfacial interactions play the role of holding the composite together. As the filler component, nanoparticle, decreases in size, the surface area begins to dominate, leading to unique behavior of the nanocomposites. The richness of the nanocomposites that can be designed by coupling various nanoparticles and complex fluid materials opens a wide field of active research. This dissertation presents a series of experimental studies on various nanocomposites using modulated differential scanning calorimetry, spectroscopic ellipsometry, dielectric spectroscopy, polarizing microscopy, and conductivity measurements of nanoparticles such as multi-wall carbon nanotubes and quantum dots on the phase transitions of several liquid crystals and polymers. The liquid crystals (LCs) and liquid crystalline polymer (LCP) of interest are: negative dielectric anisotropy alkoxyphenylbenzoate (9OO4), octylcyanobiphenyl (8CB), decylcyanobiphenyl (10CB), and isotactic polypropylene (iPP) which can form smectic liquid crystal (LC) phase. Studies have been carried out as a function of concentration and temperature spanning through various ordered phases. The results indicate a mixture of ordering and disordering effects of the nanoparticles on the phases of the complex fluids. In 9OO4/CNT system, dipole moment of liquid crystal and graphene like surface can allow a random dispersion of CNT to promote both orientational and positional order. For nCB/CNT, nCB/Quantum dot (QD) systems, nanoparticles induce net disordering effect in LC media. The effect of QDs on LC depends on the anchoring conditions and the QDs size. The results clearly demonstrate that the nematic phase imposes self-assembly on QDs to form one dimensional arrays. This leads to net disordering effect. The thermal/electrical conductivity changes in thin films of iPP/CNT sheared/un-sheared samples and it also varies with temperature for the purpose of inducing anisotropy of those properties in parallel and perpendicular to average orientation. The percolation threshold is clearly pronounced in both conductivities due to pressing and shearing treatment of the films. This will further our abilities to nano-engineer material for many important applications."

"Liquid piston gas compression utilizes a liquid to directly compress gas. The benefit of this approach is that liquid can conform to irregular compression chamber volume. The compression chamber is divided into many small little bores in order to increases the surface area to volume ratio. The heat transfer rate increases with increasing surface area to volume ratio. However, as the bore diameter becomes smaller, the viscous force increases. In order to maximize the heat transfer rate and to minimize the viscous force, computational fluid dynamics is used. ANSYS Fluent is used to simulate the liquid piston gas compression cycle. Having created the model in Fluent, different factors, including diameter, length, liquid temperature, and the acceleration are varied in order to understand how each factor affects the heat transfer and viscous energy loss. The results show that both viscous force and heat transfer rate increase as the diameter decreases. The viscous force increases and the heat transfer decreases as the length increases. Both the viscous force and heat transfer increase as the acceleration increases. The viscous force decreases as the liquid temperature increases. Results show that the highest compression efficiency of 86.4% is found with a 3mm bore radius and a short cylinder. The piston acceleration is advised to be below 0.5g in order to avoid surface instability problem."