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171.
172.
Greaves TL Weerawardena A Fong C Krodkiewska I Drummond CJ 《The journal of physical chemistry. B》2006,110(45):22479-22487
The phase behavior, including glass, devitrification, solid crystal melting, and liquid boiling transitions, and physicochemical properties, including density, refractive index, viscosity, conductivity, and air-liquid surface tension, of a series of 25 protic ionic liquids and protic fused salts are presented along with structure-property comparisons. The protic fused salts were mostly liquid at room temperature, and many exhibited a glass transition occurring at low temperatures between -114 and -44 degrees C, and high fragility, with many having low viscosities, down to as low as 17 mPa.s at 25 degrees C, and ionic conductivities up to 43.8 S/cm at 25 degrees C. These protic solvents are easily prepared through the stoichiometric combination of a primary amine and Br?nsted acid. They have poor ionic behavior when compared to the far more studied aprotic ionic liquids. However, some of the other physicochemical properties possessed by these solvents are highly promising and it is anticipated that these, or analogous protic solvents, will find applications beyond those already identified for aprotic ionic liquids. This series of protic fused salts was employed to determine the effect of structural changes on the physicochemical properties, including the effect of hydroxyl groups, increasing alkyl chain lengths, branching, and the differences between inorganic and organic anions. It was found that simple structural modifications provide a mechanism to manipulate, over a wide range, the temperature at which phase transitions occur and to specifically tailor physicochemical properties for potential end-use applications. 相似文献
173.
Punn R Feteira AM Sinclair DC Greaves C 《Journal of the American Chemical Society》2006,128(48):15386-15387
The substitution of Re into Bi2O3 allows stabilization of the delta-Bi2O3 structure by additional substitution of any lanthanide ion to give, for example, phases of composition Bi12.5La1.5ReO24.5. Some of these phases have been found to show exceptionally high oxide ion conductivity at low temperatures, ca 10-3 S cm-1 at 300 degrees C. The phases show a significant structural difference from other delta-Bi2O3 phases previously reported, with interstitial anion sites displaced further from the ideal fluorite position, (1/4,1/4,1/4). 相似文献
174.
Bayliss RD Berry FJ de Laune BP Greaves C Helgason O Marco JF Thomas MF Vergara L Whitaker MJ 《J Phys Condens Matter》2012,24(27):276001
Ferrous antimonite, FeSb(2)O(4), which is isostructural with Pb(3)O(4), and some lead-?and cobalt-doped variants of composition FeSb(1.5)Pb(0.5)O(4) and Co(0.5)Fe(0.5)Sb(1.5)Pb(0.5)O(4) have been examined by (57)Fe and (121)Sb?M?ssbauer spectroscopy. Antimony is present as Sb(3+). The presence of Pb(2+) on the antimony site induces partial oxidation of Fe(2+) to Fe(3+). There is no Verwey-type transition in which electrons are shared between iron in different oxidation states. The quasi-one-dimensional magnetic structure gives rise to situations in which weakly coupled Fe(2+) ions can coexist in a non-magnetic state alongside Fe(3+) ions in a magnetically ordered state. 相似文献