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Solubility behaviors of binary difluoromethane (HFC-32) and 1,1-difluoroethane (HFC-152a) systems with ionic liquids (ILs) 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([Emim]OTf) and 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([Bmim]OTf) have been studied by using an isothermal synthetic apparatus at temperatures (273.15, 298.15, 323.15 and 348.15) K and at pressures (0.04 to 1.0) MPa. Experimental solubility data were successfully correlated with the nonrandom two-liquid (NRTL) activity coefficient model. It was found that the solubility of hydrofluorocarbons (HFCs) in ILs is affected by the change of alkyl chain length in the cation. ' MATERIAL AND METHODSMaterials. The hydrofluorocarbon HFC-32 (CH 2 F 2 , CAS registry no. 75-10-5) and HFC-152a (CH 3 ÀCHF 2 , CAS registry

A combinatorial library of 6 × 106 cyclic peptides was synthesized in the one bead-two compound format, with each bead displaying a unique cyclic peptide on its surface and a linear peptide encoding tag in its interior. Screening of the library against K-Ras identified compounds that bound K-Ras with submicromolar affinity and disrupted its interaction with effector proteins.

Hydrofluorocarbon (HFC) + ionic liquid (IL) systems can be adopted as working pairs for compression/absorption hybrid cycles. A method of selecting novel working pairs has been proposed in this paper, that the infinite dilution activity coefficients (γ1 ∞) of working pair system need to be obtained, and the UNIFAC model is implemented to predict the activity coefficients of the working pair system. With the help of published experimental vapor–liquid equilibrium (VLE) data of 18 HFC + IL systems, 16 new group interaction parameters for four anion ILs and nine HFCs have been fitted to extend the evaluating and predicting range of HFC + IL systems for developing alternative working pairs. To validate the reliability of the method, the model parameters have been used to calculate the VLE data with the average relative deviations (ARDs) of pressures less than 8.5%. The prediction of the γ1 ∞ shows that the solubility and affinity between HFCs and ILs increase with the decrease of the γ1 ∞, which is in agreement with the experimental results. It is found by the prediction that the combinations of R32/R134 and [Tf2N]-based ILs may be two kinds of potential working pairs to improve the performances of compression/absorption hybrid cycles.