975 resultados para Di(tert-butyl)amido


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Miller traces The Roots of the Acehnese conflict to Indonesian repressive policies, specifically: exploitation of Aceh's natural resources; violence against Acehnese Civilians by Indonesian security forces; and Jakarta's failure to honor commitments to Aceh's autonomy. This contradicts the prevailing Acehnese perception of the war as a liberation struggle against colonial domination. This contradicts the prevailing Acehnese perception of the war as a Liberation struggle against colonial domination. Regional discontent in Aceh grew into separatist insurgency in the 1970s. Regional Discontent in Aceh grew into separatist insurgency in the 1970s. This provoked an increasingly martial response from the government, which involved widespread violations of Acehnese human rights. This Provoked an increasingly martial response from the government, which involved widespread violations of Acehnese human rights. East Timor's successful bid for independence in the 1990s simultaneously strengthened both Acehnese' aspirations of self-determination, and nationalists' belief in preserving Indonesia's territorial integrity. East Timor's successful bid for independence in the 1990s simultaneously strengthened both Acehnese 'aspirations of self-determination, and nationalists' belief in preserving Indonesia's territorial integrity.

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Above 110 °C the symmetric di-methyl-pyrrolidinium iodide salt forms a plastic crystal phase of interest in the area of new electrolyte materials. In this study ab initio calculations of this material has been conducted in order to assign the vibrational spectra. Raman spectroscopy measurements on the solid salt as well as on the salt dissolved in different solvents has been performed and these have been compared to the theoretical spectra. Furthermore, Raman spectra as a function of temperature have been recorded to investigate possible changes in inter-ionic interaction and/or structure through the phase transition. 1H NMR linewidth measurements as a function of temperature showed a large decrease in linewidth above 100 °C, attributed here to an increase in mobility in agreement with a previously reported phase transition at ~110 °C.

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Aluminium speciation: Aluminium speciation in NTf2 ionic liquids has a strong influence on its electrodeposition from the liquid mixture. This work probed the nature of these species and proposes that the electroactive species involved are either [AlCl3(NTf2)] or [AlCl2(NTf2)2] (e.g., see figure).


Electrodeposition of aluminium is possible from solutions of AlCl3 dissolved in the 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide (C4mpyrNTf2) ionic liquid. However, electrodeposition is dependant on the AlCl3 concentration as it only occurs at concentrations >1.6 mol L−1. At these relatively high AlCl3 concentrations the C4mpyrNTf2/AlCl3 mixtures exhibit biphasic behaviour. Notably, at 1.6 mol L−1 AlCl3, aluminium can only be electrodeposited from the upper phase. Conversely, we found that at 3.3 mol L−1 aluminium electrodeposition can only occur from the lower phase. The complex chemistry of the C4mpyrNTf2/AlCl3 system is described and implications of aluminium speciation in several C4mpyrNTf2/AlCl3 mixtures, as deduced from Raman and 27Al NMR spectroscopic data, are discussed. The 27Al NMR spectra of the C4mpyrNTf2/AlCl3 mixtures revealed the presence of both tetrahedrally and octahedrally coordinated aluminium species. Raman spectroscopy revealed that the level of uncoordinated NTf2 anions decreased with increasing AlCl3 concentration. Quantum chemical calculations using density functional and ab initio theory were employed to identify plausible aluminium-containing species and to calculate their vibrational frequencies, which in turn assisted the assignment of the observed Raman bands. The data indicate that the electroactive species involved are likely to be either [AlCl3(NTf2)] or [AlCl2(NTf2)2].

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Light scattering from small spherical particles has applications in a vast number of disciplines including astrophysics, meteorology optics and particle sizing. Mie theory provides an exact analytical characterization of plane wave scattering from spherical dielectric objects. There exist many variants of the Mie theory where fundamental assumptions of the theory has been relaxed to make generalizations. Notable such extensions are generalized Mie theory where plane waves are replaced by optical beams, scattering from lossy particles, scattering from layered particles or shells and scattering of partially coherent (non-classical) light. However, no work has yet been reported in the literature on modifications required to account for scattering when the particle or the source is in motion relative to each other. This is an important problem where many applications can be found in disciplines involving moving particle size characterization. In this paper we propose a novel approach, using special relativity, to address this problem by extending the standard Mie theory for scattering by a particle in motion with a constant speed, which may be very low, moderate or comparable to the speed of light. The proposed technique involves transforming the scattering problem to a reference frame co-moving with the particle, then applying the Mie theory in that frame and transforming the scattered field back to the reference frame of the observer.

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