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This thesis compares Chinese law with sophisticated modern models in the form of the Arbitration Act 1996 in England, and the UNCITRAL Model Law on International Commercial Arbitration, which has been adopted in Scotland. Comparison of the role of the court under these three systems shows that Chinese law fails to offer proper support and supervision in certain areas, while unduly restricting the arbitral autonomy in others. The Arbitration Act 1996 and the UNCITRAL Model Law are excellent models pointing up the directions in which Chinese arbitration law might be reformed. The thesis suggests a number of reforms which might achieve an appropriate balance between the autonomy of the arbitral process and the legitimate interests of the Chinese legal system, allowing China to become a modern, attractive arbitral forum, to the benefit of its developing trade relations.

Transition metal oxide NaxCoO2 is one of the best p-type high-temperature thermoelements for power-generation applications due to its superior thermoelectric (TE) properties and stability at high temperature. Nevertheless, efficiency is still the major limiting factor for its common use. Understanding the mechanisms associated with carrier and phonon transports is an essential step towards further enhancing the TE properties of this material. In this dissertation, the correlation of TE properties with intrinsic and extrinsic defects in NaxCoO2-δ system was investigated. It was found that resistivity ρ and thermopower S augment simultaneously with increasing concentration of oxygen vacancies δ due to the recombination of electrons and holes and average Co valence state. The total thermal conductivity κ can be reduced by minimizing δ, which is against the common understanding that oxygen vacancies usually lead to lower κ. Lattice dynamical study reveals that such anomalous κ-δ relation could be attributed to the texturing of Na+ ions stabilized by oxygen vacancies, giving rise to higher κ with δ. The dimensionless figure of merit was strongly affected by δ at lower operating temperature. The experimental results provide guideline for the variation in performance of this material system under different processing and operating environments. Divalent Zn2+ and Mg2+ impurities with closed-shell electronic configuration have been incorporated into the system and its dependence of TE properties was systematically studied. Experimental results show that doping Zn2+ within the solubility limit leads to simultaneous reduction in ρ and enhancement of S, consequently resulting in a ~ 20% enhancement in power factor. The incorporation of Mg2+, on the other hand, raises ρ and S, yet the ρ begins to decrease above a critical doping level. At certain fraction of Mg2+ doping, a remarkable ~ 50% improvement in power factor at near ambient temperature was achieved. A detailed examination between the two cases reveals that introduction of divalent impurities, which causes a reduction in Co-O-Co angle, with electronically closed-shell nature may be the decisive ingredients for enhancing the TE performance of sodium cobaltates.

Since the beginning of the industrial revolution in the late 18th century, there's an abrupt increase in need for energy and resources. Despite of advantages it offers, waste heat or energy generated by machines or vehicles exhaust is evolved into the surrounding atmosphere, resulting in the evolution of the Greenhouse effect. With rampant global warming, thermoelectricity - an environmentally benign technology that recovers waste heat and converts it directly into useful electricity or vice versa - has gradually become an interesting topic for researchers. Regardless, it has yet to be widely commercialised mainly due to its inferior energy conversion efficiency to the conventional power generators and cooling devices. The aim of this project was to explore ways of enhancing the efficiency of thermoelectric materials. NaC0204 is one of the state-of-the-art p-type thermoelectric materials to date due to its superior thermoelectric properties and stability at elevated temperatures. As a result of its layered structure, NaC0204 is highly anisotropic in thermoelectric properties. Literatures revealed that the thermoelectric properties along the in-plane direction are superior to that along the out-of-plane direction, which emphasise the significance of texture. In this work, the texturing mechanisms and the texturing process as a function of sintering duration were studied in detail and the synthesis procedure of highly textured NaC0204-; materials was optimized. The results indicate that the extent of texture increased with increasing process duration and then reached the maximum when the materials were sintered at 900°C for 12 hrs. The texturing kinetics obeys an exponential relationship, suggesting that the texturing processing is dominated by self-diffusion mechanism. The experimental evidence also shows that the extent of texture decreased when the annealing time exceeded 12 hrs. The mechanisms of such deterioration were highly due to the nature of grain growth in ceramics. Given that the Co ions in NaxC020 4-; have different valence between 3+ and 3.48+ depending on the Na content and have spins, it is expected that oxygen vacancies formed in the lattice would cause charge-spin interaction, which would have a profound effect on the thermoelectric properties. As part of current study, the oxygenation kinetics and possible mechanisms were investigated. Room temperature X-ray diffraction study shows a decrease in FWHM and a certain left shift of spectra for the oxygenated samples, suggesting an increase in d-spacing and lattice distortion as a result of oxygen deficiency. The extent of oxygen saturation increased with decreasing annealing temperature. The high oxygenation flux in the first three hours of annealing was possibly due to lower energy requirement for oxygen to occupy its vacant sites than that to interstitially occupy a site. These experimental results could be used to further study the oxygen dependence of thermoelectric performance. Moreover, the investigation of temperature effects on lattice structure of NaC02O4-; with/without oxygenation was carried out to understand oxygen contribution to the lattice structure and also thermal expansion behaviours. Refined high temperature XRD results revealed that lattice parameter a decreased and c increased over the temperature range investigated after oxygenation due to Coulomb interaction between the constituent ions. Linear thermal expansion coefficient along the a- b-axis direction is circa 1.105 x 10-5K-1 for the sample before oxygenation and 1.06 x 10-5K-1 after oxygenation. An almost three-fold increase was observed for the thermal expansion coefficient along the c-axis direction for the samples before and after oxygenation, suggesting that higher oxygen concentration suppresses the thermal expansion coefficient in all directions.