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This thesis reports the synthesis and characterisation of several layered pnictides, chalcogenides, and oxychalcogenides, with an emphasis on materials that exhibit high temperature superconductivity. High and low temperature techniques have been used to synthesise new materials and modify their properties. The majority of this work has been focused on the synthesis of superconducting materials with the general formula Ax(NH3)y(NH2)zFeSe, where A is an alkali metal. These materials are formed from a co-intercalation of alkali metals, ammonia, and alkali metal amides into the interlamellar space of pre-formed tetragonal FeSe. There is a remarkable increase in Tc associated with this intercalation, from 8 K in FeSe to a maximum of 46 K in the products. A range of characterisation techniques including neutron and X-ray diffraction, EXAFS, and SQUID magnetometry have been used to identify a variety of crystal structures, compositions, and properties adopted by these materials. The synthesis procedure of these materials where, A = Na and K, has been studied in-situ via powder X-ray diffraction at world-class central facilities, revealing new phases, intermediates, and activation energies. The Kx(NH3)y(NH2)zFeSe phases are found to undergo a topotactic decomposition step to become Kx'Fe2-y'Se2 phases on annealing, which has also been studied by in-situ powder X-ray diffraction. Additional studies on Na1-xFe2-yAs2 and CaFeSeO have been performed. Na1-xFe2-yAs2 is the product of a room temperature deintercalation of sodium and iron from NaFeAs, which changes the superconducting properties of the material. XAFS measurements have been used to characterise the local structure of the materials, which supports the conclusion that iron is deintercalated from the parent material and gives new insight into the effect of the iron vacancies on the local structure. CaFeSeO is a newly discovered material that adopts a never-before-seen crystal structure, which has been solved from powder X-ray diffraction data. Intricate vacancy ordering exists in the material, which contributes to a peculiar mixture of magnetic behaviours including signatures of a spin glass, ordered antiferromagnet, and an ordered ferromagnetic component. All of these behaviours however, can be rationalised by the nuclear and magnetic structure of the material that have been refined using powder neutron diffraction.

The thesis comprises a collection of ten published works in the field of individual differences and student learning in a, mainly, higher education context involving undergraduate student participants. The works revolve primarily around three principal conceptual areas, identified within the field on the grounds of being recognized mediators of learning and achievement - namely, learning style, academic control beliefs and student self-evaluation. Students' perceptions of themselves as learners, and their use of various processes to regulate their learning, have been identified as critical factors in the analyses of academic development and achievement. On the basis of this, the thesis presents a programme of work concerned with establishing a clearer understanding of the conceptualisation, measurement and pedagogical utility of learning style, academic control beliefs, student peer assessment and student self-assessment. It is argued that each of these constructs plays a major role in the development and practice of student self-regulated learning (SRL). SRL theory therefore provides the theoretical context which unifies and integrates the principal research areas addressed in the thesis. Accordingly, learning style, academic control beliefs and student self-evaluation are suggested as key component processes of SRL. The study of SRL is increasingly being identified as highly relevant to both research and practice-based pedagogy (e.g. Baumert et al., 2000; Zimmerman & Schunk, 2001). It is therefore further suggested that the existing conceptual bases of SRL may represent the foundations for the development of a composite theory capable of characterising, and facilitating, translational modelling of much of the work involving individual differences in learning.