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چکیده
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In this work we prepared three new amino acid based ionic liquids (AAILs), 1-decyl-3-methylimidazolium glycinat ([C10mim]Gly), 1-decyl-3-methylimidazolium alaninat ([C10mim]Ala) and 1-decyl-3-methylimidazolium valinate ([C10mim]Val) using 1-decyl-3-methylimidazolium bromide ([C10mim]Br) and glycine, alanine and valine. Some thermodynamic properties such as of density, speed of sound, molar volume, standard entropy, crystal energy, thermal expansion coefficients and isentropic compressibility of investigated AAILs were measured at 293.15-333.15 K. Our results show that the density of pure AAILS decrease by increase the size of counter-ion: [C10mim]Gly > [C10mim]Ala > [C10mim]Val. According to this trend, the increase in anionic amino acid size cause to decrease in densty. In other word, the larger size in anionic amino acids lead to more compact structur of these AAILs; The obtained data for molar volume confirm these results. The order of increase in molar volume is: [C10mim]Gly < [C10mim]Ala < [C10mim]Val. In the other part of this work, the thermodynamic properties of aqueous solution of investigated AAILs such as isentropic compressibility, apparent molar volume, apparent molar isentropic compressibility, change in apparent molar volume from micellization at 288.15-313.15K and standard Gibbs free energy from micalization at 298.15K were calculated, and the resultant data compared to obtained data for [C10mim]Br. The resultant data for compressibility show the following order: [C10mim]Br > [C10mim]Gly ≈ [C10mim]Ala > [C10mim]Val. Higher degree of binding of Br- to the surface of [C10mim]Br cause to liberation of some water moleculs and decrease in elctrostriction. This cause to higher compressibility of aqueous solution of [C10mim]Br. In the next part of the projct, the thermodynamic properties of aqueous solution of [C10mim]Br, 1-dodecyl-3-methylimidazolium bromide ([C12mim]Br), sodium dodecyl sulfate (SDS) in 0.7 mol/kg of aqueous solution of glycine, alanine an
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