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associates. Good peak symmetry and system efficiency for analysis of basic compounds are also achieved by use of mobile phases containing organic amines as silanol blockers. To suppress free silanol groups, an addition of ionic liquids (ILs) to mobile

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in aqueous solutions of non-ionic surfactants [ 22 ]. Recently, the use of room temperature ionic liquids (ILs) as alternatives to surfactants or organic solvents has been reported in CPE [ 23 ] methods. ILs are less toxic than organic

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Abstract  

A brown and transparent ionic liquid (IL), [C4mim][FeCl4], was prepared by mixing anhydrous FeCl3 with 1-butyl-3-methylimidazolium chloride ([C4mim][Cl]), with molar ratio 1/1 under stirring in a glove box filled with dry argon. The molar enthalpies of solution, Δs H m, of [C4mim][FeCl4], in water with various molalities were determined by a solution-reaction isoperibol calorimeter at 298.15 K. Considering the hydrolyzation of anion [FeCl4] in dissolution process of the IL, a new method of determining the standard molar enthalpy of solution, Δs H m 0, was put forward on the bases of Pitzer solution theory of mixed electrolytes. The values of Δs H m 0 and the sum of Pitzer parameters:
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$(4\beta _{Fe,Cl}^{(0)L} + 4\beta _{C_4 mim,Cl}^{(0)L} + \Phi _{Fe,C_4 mim}^L )$$ \end{document}
and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$(\beta _{Fe,Cl}^{(1)L} + \beta _{C_4 mim,Cl}^{(1)L} )$$ \end{document}
were obtained, respectively. In terms of thermodynamic cycle and the lattice energy of IL calculated by Glasser’s lattice energy theory of ILs, the dissociation enthalpy of anion [FeCl4], ΔH dis≈5650 kJ mol−1, for the reaction: [FeCl4](g)→Fe3+(g)+4Cl(g), was estimated. It is shown that large hydration enthalpies of ions have been compensated by large the dissociation enthalpy of [FeCl4] anion, Δd H m, in dissolution process of the IL.
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Transformed from heterogeneous to homogeneous state, an ionic liquid (IL)-based Suzuki coupling reaction was successfully implemented in a continuous microflow system. Triethylamine (Et3N) was introduced as the base, and N-methylpyrrolidinone (NMP) was used as the solvent of boronic acid, which brought about the first improvement on the reaction performance. Then, the implementation of this reaction in a continuous microflow system brought about further improvement on the reaction yield and selectivity due to better mixing condition. The combination of IL as the reaction medium and the continuous microflow system as the reactor in this work exhibited great potential for efficient Suzuki coupling reactions.

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Abstract  

We investigated the features of the glass transition relaxation of two room temperature ionic liquids using DSC. An important observation was that the heat capacity jump, that is the signature of the glass transition relaxation, shows a particularly strong value in this type of new and promising materials, candidates for a range of applications. This suggests a high degree of molecular mobility in the supercooled liquid state. The study of the influence of the heating rate on the temperature location of the glass transition signal, allowed the determination of the activation energy at the glass transition temperature, and the calculation of the fragility index of these two ionic glass-formers. It was concluded that this kind of materials belong to the class of relatively strong glass-forming systems.

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Introduction Ionic liquids have received considerable attention recently for their wide range of applications, which are invariably possible due to attractive physical and chemical properties of these materials [ 1 – 5 ]. These

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Introduction As green solvents, ionic liquids especially air and water stable ionic liquids have gained great attention [ 1 – 3 ]. In recent decades, the study of ionic liquids is focused on the chemical reaction and separation

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alternative solvents for separations, chemical synthesis, electrochemistry and catalysis. Generally, they are nonvolatile, non-explosive, recyclable, easy to handle and thermally robust. The work on deep desulfurization by ionic liquids was well summarized in

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Introduction Ionic liquids (ILs) have a widespread use in many areas of chemistry due to features of first-rate chemical and thermal stabilities, good electronic and ionic conductivities and ability to dissolve a great variety

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and 43% ee% for α-methylstyrene. It would be of interest if we could shorten the reaction time and improve the enantioselectivity of the asymmetric reaction without the use of volatile organic solvent. Room temperature ionic liquids (RTILs) are

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