Absorption of ultrasonic waves in aqueous solutions of α-cyclodextrin with alkylpyridinium or alkyltrimethylammonium bromides

Measurements of the absorption coefficient, α/f², of aqueous solutions of α-cyclodextrin with alkylpyridinium bromides C_nH_2n+1C₅H₄NBr or alkyltrimethylammonium bromides C_nH_2n+1N(CH₃)₃Br (n = 8, 10, 12), were carried out at 15, 25, 35 and 45°C in the concentration range 0.01 M to 0.04 M and frequency range 1 MHz to 150 MHz. The occurrence of two ultrasonic relaxation processes has been noted. The obtained results have been compared with data published previously for sodium alkyl sulfates.