10 resultados para Spin multiplicity
em Deakin Research Online - Australia
Resumo:
The ability to image electrochemical processes in situ using nuclear magnetic resonance imaging (MRI) offers exciting possibilities for understanding and optimizing materials in batteries, fuel cells and supercapacitors. In these applications, however, the quality of the MRI measurement is inherently limited by the presence of conductive elements in the cell or device. To overcome related difficulties, optimal methodologies have to be employed. We show that time-efficient three dimensional (3D) imaging of liquid and solid lithium battery components can be performed by Sectoral Fast Spin Echo and Single Point Imaging with T1 Enhancement (SPRITE), respectively. The former method is based on the generalized phase encoding concept employed in clinical MRI, which we have adapted and optimized for materials science and electrochemistry applications. Hard radio frequency pulses, short echo spacing and centrically ordered sectoral phase encoding ensure accurate and time-efficient full volume imaging. Mapping of density, diffusivity and relaxation time constants in metal-containing liquid electrolytes is demonstrated. 1, 2 and 3D SPRITE approaches show strong potential for rapid high resolution (7)Li MRI of lithium electrode components.
Resumo:
This work comprehensively explores the implications of multiplicty of international judicial bodies on the coherent application of public international law. It carried out an in-depth analysis of the underlying reasons for the multiplicity, a thorough discussion of the benefits and the challenges presented by this development, its theoretical dimensions and solutions suggested to mitigate the challenges. The work locates the root causes of these challenges in the normative and institutional expansions of international law without a corresponding coordination of the activities of the ¿proliferating¿ judicial bodies. The challanges are systemic in nature. Clearly, because of their systemic nature, the impacts of these challenges are not limited to the specific courts, cases and parties implicated, but have a ripple effect that reverberates throughout the system. Therefore, the mitigation of the impacts of these challenges is of a paramount importance for the credibility, predictability, legitimacy and overall integrity of the international legal system and the eventual augmentation of the ¿compliance pull¿ garnered as a result.
Resumo:
Three new cobalt(ii) complexes, [Co(L12)2](BF4)2 (1), [Co(L14)2](BF4)2·H2O (2) and [Co(L16)2](BF4)2·H2O (3), where L12-16 are N3-Schiff bases appended with linear C12-16 carbon chains at the nitrogen atoms, were obtained in good yields by facile one-pot reactions. The single crystal X-ray structure of complex 1 shows a tetragonally compressed CoN6 coordination geometry. The melting temperatures of 1-3 were lower than 373 K, while their decomposition temperatures were above 473 K. All complexes have high-spin Co(ii) centres at 300 K and exhibit a columnar mesophase above 383 K. Complexes 1 and 3 showed normal thermal spin-crossover behaviour with weak hysteresis loops at about 320 K. Hence, these complexes showed uncoupled phase transitions (class iiia). The values for the Seebeck coefficient (Se) of the cobalt redox couples formed from 1 and 2 were 1.89 ± 0.02 mV K-1 and 1.92 ± 0.08 mV K-1, respectively, identifying them as potential thermoelectrochemical materials.