Thesis advisor: David A. Broido / Using density functional perturbation theory and a full solution of the linearized phonon Boltzmann transport equation (BTE), a parameter-free theory of semiconductor thermal properties is developed. The approximations and shortcomings of previous approaches to thermal conductivity calculations are investigated. The use of empirical interatomic potentials in the BTE approach is shown to give poor agreement with measured values of thermal conductivity. By using the adiabatic bond charge model, the importance of accurate descriptions of phonon dispersions is highlighted. The extremely limited capacity of previous theoretical techniques in the realm of thermal conductivity prediction is highlighted; this is due to a dependence on adjustable parameters. Density functional perturbation theory is coupled with an iterative solution to the full Boltzmann transport equation creating a theoretical construct where thermal conductivity prediction becomes possible. Validation of the approach is demonstrated through the calculation of a range of thermal properties for a set of polar and non-polar semiconductors which are compared with measured values. The agreement between theory and measurement is very good, confirming the promise of the theoretical approach. Due to the significant computational effort required by the parameter-free calculations, new forms for room temperature relaxation time approximations are derived. The resulting forms produce thermal conductivity values in very good agreement with the ab initio data across a wide temperature range. It is therefore shown that accurate relaxation time approximations can be developed, fixing the adjustable parameters to the ab initio theory avoiding any comparison with measured data. This approach improves the accuracy of phonon relaxation times compared with previous models. / Thesis (PhD) — Boston College, 2009. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Physics.

Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2012. / Crystal engineering is the synthesis of new crystalline materials with specific chemical and physical properties which allows the comprehensive understanding of the non covalent interactions that occur between molecules in the crystalline state. This has lead to extensive work being done in terms of host design. The study of non-covalent interactions formed by these materials is crucial to understanding many biological processes. This study focuses on the inclusion compounds of 1, 4-bis (diphenylhydroxymethyl) benzene H, a host compound engineered by EWeber, that conforms to Weber's rules for host design as it is bulky, rigid, and has hydroxyl moieties that act as hydrogen-bonding donors. A Cambridge Structural Database (CSDversion 5.33) search has revealed that no research has been conducted on this host compound. Characterization of the compounds were conducted using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC}, hot stage microscopy (HS), gas chromatography (GC}, powder X-ray diffraction(PXRD} and single X -ray diffraction. Host: guest ratios determined from TG analysis were correlated with structural analysis results.

by Wong Sai-peng. / Bibliography: leaves 116-119 / Thesis (Ph.D)--Chinese University of Hong Kong, 1984

Thesis (M.Phil.)--Chinese University of Hong Kong. / Bibliography: leaves 85-86.

Lai Kai-wing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1978. / Bibliography: leaves 127-130.

by Choy Juliet. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 142-144). / Text in English; abstract also in Chinese. / by Choy Juliet. / List Of Figures --- p.iii / List of Tables --- p.xxii / Abstract --- p.xxiii / Acknowledgments --- p.xxvi / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Review On Free Bose Gases --- p.6 / Chapter 2.1 --- 3D Free Bose Gas --- p.6 / Chapter 2.2 --- Bose-Einstein Condensation in Three Dimensions --- p.9 / Chapter 2.3 --- Ideal Bose Gas in Two Dimensions [15] --- p.12 / Chapter 3 --- Bose-Einstein Condensation in a 3D cubic box --- p.15 / Chapter 3.1 --- Effects of boundaries on Bose-Einstein Condensation --- p.15 / Chapter 3.2 --- Bose-Einstein condensation in a 3D cubic box --- p.17 / Chapter 3.3 --- Numerical results for bosons in a 3D cubic box --- p.20 / Chapter 4 --- Bosons in harmonic potentials --- p.25 / Chapter 4.1 --- 3D Isotropic harmonic potential --- p.26 / Chapter 4.2 --- 3D Anisotropic harmonic potentials --- p.32 / Chapter 4.3 --- 2D Harmonic potential --- p.37 / Chapter 4.4 --- ID Harmonic potential --- p.42 / Chapter 5 --- Bosons trapped in highly anisotropic harmonic potentials --- p.47 / Chapter 5.1 --- Two-step Condensation in highly anisotropic harmonic traps --- p.48 / Chapter 5.2 --- The freezing out of the degrees of freedom --- p.51 / Chapter 6 --- Bosons in q-deformed potentials --- p.56 / Chapter 6.1 --- The q-deformed harmonic oscillator --- p.57 / Chapter 6.2 --- Condensation of a Bose gas with the q-deformed harmonic oscillator energy spectrum --- p.60 / Chapter 7 --- Rotational and density related properties of trapped bosons: the formalism --- p.77 / Chapter 7.1 --- Rotational properties of trapped bosons --- p.77 / Chapter 7.2 --- Density related properties of trapped bosons --- p.82 / Chapter 8 --- Rotational and density related properties of trapped bosons: results for harmonic and q-deformed oscillators --- p.88 / Chapter 8.1 --- Rotational property of bosons in harmonic andq-deformed potentials --- p.88 / Chapter 8.2 --- Density related properties of bosons in harmonic and q-deformed potentials --- p.103 / Chapter 9 --- Thermal properties of bosons in the field of a superposition of double-well potentials --- p.121 / Chapter 9.1 --- Numerical study of bosons in the field of a superposition of double- well potentials --- p.121 / Chapter 9.2 --- Low temperature thermodynamics of bosons in a double well po- tential --- p.129 / Chapter 10 --- Conclusion --- p.139

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Natural-synthetic hydrid biomaterials have been isolated from the growth of Alcaligenes latus and Pseudomonas oleovorans in the presence of diethylene glycol (DEG). A. latus could cometabolise DEG with 10 g/L glucose, while DEG was consumed by P. oleovorans with 20 mM sodium octanoate or octanoic acid. The presence of DEG in bioprocessing systems for the production of short chain length (scl-) and medium chain length (mcl-) PHAs consequently lowered cell viability and PHA yield. Cell morphology was slightly changed, but the PHA inclusion bodies apparently were not. DEG affected the composition of the mclPHA which was confirmed to be polyhydroxyoctanoate (PHO) with a significant increase in the C8 component. Gas chromatography-mass spectrometry (GC-MS) was used to quantitatively monitor DEG in the system and revealed its cellular adsorption. Intracellularly, the DEG significantly decreased the molar weight of the mclPHA and sclPHA. P1PH NMR, 2-D COSY and HSQC spectra confirmed that the polymer samples consisted of PHA chains terminated by DEG. Similar to the cultivation of P. oleovorans with DEG, the presence of PEG200 and PEG400 also had an effect on cell growth, PHO yield and cell viability. Furthermore, a hybrid copolymer of PHO-PEG200 was synthesised. The synthesis of these natural-synthetic hybrid copolymers could lead the way for a wide variety of PHA-PEG copolymers with a range of bioactive properties. All thermal properties of PHB were higher than those of PHB-DEG. This may be due to a combination of lower PHB molecular weight and termination of the chains by DEG, i.e. ???DEGylation???. However, PHB-DEG was more elastomeric when compared to PHB, showing properties similar to its copolymer with 20 mol% 3-hydroxyvalerate. Contact angles revealed that the PHB-DEG film was slightly more hydrophilic than PHB. Despite the large difference in their respective proportions, the comparatively small DEG component exerted an influence on chain confirmation, such that solvent casting under humid conditions apparently induced self-assembly and formed a disordered microporous film. DEGylation of PHO also had noticeable effects on the physiochemical properties of the biopolymer. A major decrease in molecular weight, together with the termination of hydrophobic PHO chains with hydrophilic end-groups resulted in changes to its thermal properties when compared to PHO. In comparison to PHO, solvent cast films of PHO-DEG were apparently less flexible, but more hydrophilic.