@article {2460,
	title = {Hydrophobicity/Hydrophilicity of 1-Butyl-2,3-dimethyl and 1-Ethyl-3-methylimodazolium Ions: Toward Characterization of Room Temperature Ionic Liquids},
	journal = {Journal of Physical Chemistry B},
	volume = {113},
	number = {44},
	year = {2009},
	note = {ISI Document Delivery No.: 510QMTimes Cited: 2Cited Reference Count: 52Kato, Hitoshi Miki, Kumiko Mukai, Tomohiro Nishikawa, Keiko Koga, Yoshikata},
	month = {Nov},
	pages = {14754-14760},
	type = {Article},
	abstract = {We continue to experimentally characterize the constituent ions of room temperature ionic liquids in terms of their interactions with H2O. By using the so-called 1-propanol probing methodology, we experimentally index the relative hydrophobicity/hydrophilicity of a test ion. In this paper, we examine 1-butyl-2,3 dimethylimidazolium (abbreviated as [C(4)C(1)mim](+)) and 1-ethyl-3-methylimidazolium ([C(2)mim](+)). We found that [C(4)C(1)mim](+) dissociates completely in dilute aqueous solution less than 0.006 mol fraction, and hence, its hydrophobicity/hydrophilicity could be determined. The results indicate that [C(4)C(1)mim](+) is highly amphiphilic with much stronger hydrophobicity and hydrophilicity than normal ions. Our earlier similar studies indicated the same conclusion for such typical constituent ions as 1-butyl-3-methylimidazolium ([C(4)mim](+)) PF6-, CF3SO3-, and N(SO2CF3)(2)(-). Hence, we suggest that the constituent ions of room temperature ionic liquids that we have studied so far are all amphiphiles with much stronger hydrophobicity and hydrophilicity than normal ions. We found, furthermore, that the hydrophobicity and hydrophilicity of [C(4)C(1)mim](+) are stronger than those for [C(4)mim](+). A possible reason for higher hydrpohilicity is discussed in terms of strong acidic character of H on the C(2) of the imidazolium ring, which tends to attract the delocalized positive charge toward itself oil forming a hydrogen bond to H2O. On replacing it with CH3 in [C(4)C(1)mim](+), the lack of acidic H enhances the positive charge in the vicinity of N-C-N in the ring that interacts with the surrounding H2O strongly to an induced dipole of O of the H2O. For [C(2)mim](+), we found it does not dissociate completely, even in dilute aqueous solution, and hence, we could not characterize it within the present methodology.},
	keywords = {1-BUTYL-3-METHYLIMIDAZOLIUM BROMIDE, AGGREGATION BEHAVIOR, ALKYL CHAIN-LENGTH, APPROACH, AQUEOUS-SOLUTIONS, HOFMEISTER SERIES, MIXING SCHEMES, MOLECULAR-ORGANIZATION, partial molar enthalpy, PHYSICOCHEMICAL PROPERTIES, THERMODYNAMIC},
	isbn = {1520-6106},
	url = {<Go to ISI>://000271105600027},
	author = {Kato, H. and Miki, K. and Mukai, T. and Nishikawa, K. and Koga,Yoshikata}
}
@article {1627,
	title = {Toward understanding the Hofmeister series. 3. Effects of sodium halides on the molecular organization of H2O as probed by 1-propanol},
	journal = {Journal of Physical Chemistry A},
	volume = {110},
	number = {5},
	year = {2006},
	note = {ISI Document Delivery No.: 011VUTimes Cited: 15Cited Reference Count: 42},
	month = {Feb},
	pages = {2072-2078},
	type = {Article},
	abstract = {We investigated the effects of NaF, NaCl, NaBr, and NaI on the molecular organization of H2O by a calorimetric methodology developed by us earlier. We use the third derivative quantities of G pertaining to I-propanol (1P) in ternary 1P-asalt-H2O as a probe to elucidate the effects of a salt on H2O. We found that NaF and NaCl worked as hydration centers. The hydration numbers were 19 +/- 2 for NaF and 7.5 +/- 0.6 for NaCl. Furthermore, the bulk H2O away from the hydration shell was found unaffected by the presence of Na+, F-, and Cl-. For NaBr and NaI, in addition to the hydration to Na+, Br- and I- acted like a hydrophilic moiety such as urea. Namely, they formed a hydrogen bond to the existing H2O network and retarded the fluctuation nature of H2O. These findings were discussed with respect to the Hofmeister ranking. We suggested that more chaotropic anions Br- and I- are characterized as hydrophiles, whereas kosmotropes, F- and Cl-, are hydration centers.},
	keywords = {25-DEGREES-C, AQUEOUS-SOLUTIONS, CHEMICAL-POTENTIALS, DIELECTRIC-SPECTROSCOPY, INTERMOLECULAR INTERACTIONS, LIQUID WATER, MIXING SCHEMES, NONELECTROLYTES, partial molar enthalpy, TERT-BUTYL ALCOHOL},
	isbn = {1089-5639},
	url = {<Go to ISI>://000235297400050},
	author = {Westh, P. and Kato, H. and Nishikawa, K. and Koga,Yoshikata}
}
@article {717,
	title = {Non-ideality of methanol solution{\textquoteright}s of artificial serum in the mole fraction range from 5 x 10(-4) to 5 x 10(-3) at 25 degrees C},
	journal = {Fluid Phase Equilibria},
	volume = {207},
	number = {1-2},
	year = {2003},
	note = {ISI Document Delivery No.: 683WUTimes Cited: 0Cited Reference Count: 20},
	month = {May},
	pages = {301-317},
	type = {Article},
	abstract = {Vapour pressure and excess partial molar enthalpy were measured at 25 degreesC for solutions of methanol in H2O and artificial serum solutions. The mole fraction range studied was from 5 x 10(-4) to 5 x 10(-3). From the vapour pressure data, the partial pressures were determined by the Barker{\textquoteright}s and Boissonnas{\textquoteright} methods. Various thermodynamic functions were then calculated from them. The curve-fitting (Barker{\textquoteright}s method) gave the osmotic coefficients very close to unity in all the cases, including serum solutions. The purely numerical method without resorting to any fitting function (Boissonnas{\textquoteright} method), on the other hand, produced the osmotic coefficient significantly larger than unity in serum solutions studied. This is consistent with the findings by the earlier freezing point depression study on ethanol in human blood serum solutions. The partial molar enthalpy data indicated highly non-ideal behaviours also, particularly in serum solutions. The detailed mechanism causing non-ideality even at this dilute concentration range is yet to be elucidated. (C) 2003 Elsevier Science B.V. All rights reserved.},
	keywords = {ALBUMIN, AQUEOUS-SOLUTIONS, Barker{\textquoteright}s and Boissonnas methods, BINDING, chemical potential, data analysis by, DILUTE, LAW REGION, methanol in H2O and serum with bovine serum, osmotic coefficient, partial molar enthalpy, VAPOR-PRESSURES, WATER},
	isbn = {0378-3812},
	url = {<Go to ISI>://000183174700020},
	author = {Ralloff, K. P. G. and Westh, P. and Purssell, R. A. and Pudek, M. and Koga,Yoshikata}
}
@article {4958,
	title = {Interactions in D-fructose-1-propanol-H2O: the effect of D-fructose on the molecular organization of liquid H2O},
	journal = {Fluid Phase Equilibria},
	volume = {171},
	number = {1-2},
	year = {2000},
	note = {ISI Document Delivery No.: 349EQTimes Cited: 5Cited Reference Count: 27},
	month = {May},
	pages = {151-164},
	type = {Article},
	abstract = {Densities of binary aqueous solutions of D-fructose (abbreviated as FR hereinafter) were determined in a much wider mole fraction range than available in literature. In contrast to hydrophobic solutes, the partial molar volume of FR, V-FR, does not show an initial decrease on increasing the mole fraction of FR, x(FR). In order to learn more about the effect of FR on the molecular organization of liquid H2O, the excess chemical potentials and partial molar enthalpy of 1-propanol (1P) were determined in ternary 1P-FR-H2O system. Namely, the detailed thermodynamic behaviour of 1P in the ternary system was used as a probe to elucidate the effect of FR on liquid H2O. In comparison with earlier results of the temperature dependence of tert-butanol (TBA)-TBA interaction functions, addition of FR seems to have a similar effect of temperature increase on the molecular organization of H2O. We suggest that addition of FR tends to decrease the global average of hydrogen bond probability of H2O. (C) 2000 Elsevier Science B.V. All rights reserved.},
	keywords = {25-DEGREES-C, AQUEOUS-SOLUTIONS, BUTYL ALCOHOL-SOLUTIONS, chemical potential, CHEMICAL-POTENTIALS, D-fructose-1-propanol-H2O, effect of beta-D-fructose on H2O, INTERMOLECULAR INTERACTIONS, MIXING SCHEME, PARTIAL MOLAR ENTHALPIES, partial molar enthalpy, TRANSITION, VOLUME, VOLUMES, WATER-RICH REGION},
	isbn = {0378-3812},
	url = {<Go to ISI>://000089031000011},
	author = {To, E. C. H. and Westh, P. and Trandum, C. and Hvidt, A. and Koga,Yoshikata}
}
