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Stacked commercial second generation (2G) high temperature superconducting (HTS) tapes has been demonstrated to have great field trapping ability, with superior mechanical, thermal properties and crossed-field performance to HTS bulks. HTS stacks are considered as a very promising candidate for superconducting permanent magnets, which can be used for many applications like superconducting machines and levitation devices. However, the current magnetization methods for HTS stacks are the conventional magnetization methods developed for HTS bulks decades ago, which have various limitations. On the other hand, the recent progress on HTS flux pumping technology enables HTS coils to be successfully magnetized in an effective and efficient way. In this thesis, these two concepts were combined for the first time. Flux pumping for HTS stacks was proposed and developed as a new magnetization technique. I employed two types of flux pumps, the rotating magnet flux pump and the rectifier type flux pump, to magnetize the modified HTS stacks. The design of the flux pumps, the experimental results and the analysis of the observed behaviours are presented in the thesis. This research provides a new direction in the magnetization of HTS permanent magnets, which has the potential to make HTS permanent magnets more practical with lighter, more compact and efficient magnetization setups.

Allergy is an IgE-mediated hypersensitivity that is triggered by allergens, leading to various physical symptoms including eczema, asthma, diarrhoea and cardiac arrest. The molecular mechanism for allergenicity elicitation with critical disease symptoms is yet beyond understanding, despite the development in knowledge of crystallographic structures of various protein allergens, and the identification of immunoglobin-binding protein fragments, which are usually called epitopes. We also lack a robust prediction methodology for a new protein's potential to trigger allergic reactions, which leads to an equally important question of differentiating structurally similar proteins and identify their own capability to trigger allergic reaction. It is clear that we are in need of efficient multi-scale methods for understanding the dynamical properties of allergen proteins in a whole at the molecular level, but traditional computational methods are restricted not only by the coupling of protein dynamics across time scales, but also their demanding cost to extract multi-scale information if an efficient new representation of the same protein system cannot be established. We try to solve these problems by taking a graph-theoretical approach. By representing the atomic level description of an allergen structure using a mathematical abstraction called graph, we extract the physical-chemical details and map them into a weighted graph which then is explored by Markov random explorers. Three graph-based methods, namely, Markov Stability, Markov Transient and the bond-bond Propensity have been proposed and applied in our cases, to extract dynamical information for understanding the allergenicity problem. These methods are linear or sub-linear with respect to the number of nodes in a protein graph, so they are far more efficient than the previous methods. Two allergen protein families have been studied in this thesis: the bi-cupin super-family proteins, exemplified by the peanut allergen proteins Ara h 1, 2 and 6; and the PR-10 super-family including the pollen allergens Bet v 1 and 2. The hierarchical structural properties as well as their inherent correlation between the immunoglobulin-binding sites and the the active sites are studied and compared. Also the difference between allergens and their negative controls are discussed. In parallel, theoretical mutagenesis is taken to identify hot spots which contribute to the changes in the physical-chemical properties of an allergen protein. Through these attempts, we are able to find a series of amino acid residues that can be potential targets for designing targeted-drugs, as well as full comprehension of the allergenicity problem. Since the protein-protein interaction of an allergen and the immunoglobulin has not been looked at, and that we are in lack of full, feasible crystal structures to critically study the effects of an allergen before and after binding to an immunoglobulin such as type E, we study human cell-cycle cyclin-dependent kinase 2 (Cdk2) and its various structures along with binding counter-parties using our graph-theoretical suite. Our results indicate that hidden information propagation pathway between the kinase and its binding parties can be exposed, and the identified amino acid residues are being considered as possible targets for further research.

Synthetic polymers intended for use in biomedical applications require the additional criteria of biocompatibility and sometimes biodegradability included within the design parameters along with mechanical properties, manufacturability, and other properties depending on the specific application in mind. The composition of the monomer and the type of linker within the main chain polymer as well as the chemical reactivity of these chemical entities will define the degradation rates and the conditions under which degradation will or will not occur. However, biocompatibility is usually a built-in characteristic related to the polymer (and monomer) composition and is not easily engineered into an existing polymer by conversion from a non-biocompatible to a biocompatible polymer. Consequently, a majority of the biocompatible polymers used in medical devices or evaluated for biomedical uses are composed of substances that are natural metabolites or known to be biocompatible and nontoxic. Using this design principle, a number of successful examples of biocompatible polymers have been reported such as poly(lactic acid), poly(glycolic acid), and their copolymers, and today, all of these polymers are used in US and EU approved devices. For similar reasons, glycerol-based polymers are attracting increasingly more attention for both fundamental studies and practical applications. Various glycerol polymer architectures from linear to dendritic have been reported for pure polyglycerol ethers and carbonates as well as copolymers with hydroxyacids, for example, to give polyether esters or polycarbonate esters. Herein, the design and synthesis of glycerol-based polycarbonates via copolymerization of epoxide and carbon dioxide is described. The underlying chemistry that affords these glycerol-based polycarbonates will be discussed. Their structural characteristics, their chemical, physical, and rheological properties, and as well as their applications with a focus on drug carrier will also be covered.

Salt crystal whiskers were grown from salt solution saturated nanoporous silica coatings. Coated substrates were partially immersed into an aqueous potassium chloride solution and then kept in a controlled relative humidity chamber for whisker growth. The salt solution was first wicked into the coating by capillary action, and then evaporation ensued and a supersaturated condition was reached. Crystals grew from the surface by a base growth mechanism in which salt ions were added to the surface of the crystal that was in contact with the nanoporous coating. Optical microscopy and SEM results demonstrated this mechanism. Crystals with whisker morphologies, typically 2 - 50 µm in lateral dimension and up to ~1 cm in length, emerged from the coating surface at a position above the original liquid level. Sheet-like crystals also formed from whiskers that had fallen flat onto the porous coating surface. Inspired by the sheet formation mechanism and liquid transportation phenomenon, a seeding technique was developed to reduce whisker width. Attritor ground salt particles were placed on the nanoporous coating surface to initiate simultaneous whiskers growth and salt nano-whiskers with lateral dimension as small as 50 nm were obtained on the surface of the coating. This crystal growth method can be applied to different materials, namely water soluble materials, and creates whisker crystals with controllable size and location on the nanoporous coating. Open celled foam is a three dimensional structure. In some applications, other materials are coated on internal surface of the foam to provide desired final product functionality. Because of their complicated 3D structures, coating onto foam is challenging. A new coating process that combines dip coating and spin coating was developed. Dip coating step was used to load the solution into the foam and a spin treatment step was added to remove the trapped liquid and redistribute the liquid to obtain uniform coating. The dip and spin process was also used to create -alumina and zeolite coatings, which are of interest for catalysis applications.