A new mechanism of ultrasonic absorption in aqueous solutions of rigid macromolecules

The temperature- and frequency-dependences of the ultrasonic absorption in lyotropic liquid crystals of rod-like FD virus particles have been measured with the ultrasonic beam being parallel or perpendicular to the rod axis. The experimental results show a strongly anisotropic ultrasonic absorption in the lyotropic liquid crystals, which varies with temperature exactly as the shear viscosity of water. Experimental results are in good agreement with the following model for the absorption process. The authors believe that the absorption arises from differential flow of water between the relatively long and rigid rod-like macromolecules. This mechanism of ultrasonic absorption becomes dominant for frequencies of 1-100 MHz. The validity of this mechanism is, however, not restricted to the special lyotropic crystals discussed here. Instead, this absorption process is expected to be important also for other macromolecular solutions whenever the dissolved macromolecular objects have a sufficiently large linear dimension in the direction parallel to the sound beam.<<ETX>>

[1]  K. Dransfeld,et al.  High Frequency Phonons on Surfaces and in Periodic Structures , 1988 .

[2]  L. V. Zandt.  Resonant microwave absorption by dissolved DNA. , 1986 .

[3]  K. Dransfeld,et al.  Propagation and Generation of High-Frequency Ultrasonic Waves in Magnetically Oriented Lyotropic Liquid Crystals , 1986 .

[4]  Carl Wetter.  Die Flüssigkristalle des Tabakmosaikvirus , 1985 .

[5]  J. Witz,et al.  Ultrasonic absorption in tobacco mosaic virus and its protein aggregates. , 1985, Journal of molecular biology.

[6]  G. Maret,et al.  Biomolecules and Polymers in High Steady Magnetic Fields , 1985 .

[7]  E. Morris,et al.  Ultrasonic relaxation of agarose and carrageenan gels. The role of solvent , 1982 .

[8]  U. Kreibig,et al.  Light Diffraction of in vitro Crystals of Six Tobacco Mosaic Viruses , 1980 .

[9]  G. Maret,et al.  Velocity of high frequency sound waves in oriented DNA fibres and films determined by Brillouin scattering , 1979 .

[10]  J. Ketterson,et al.  Sound Propagation in Liquid Crystals , 1979 .

[11]  S. Letcher,et al.  Ultrasonic Propagation in Liquid Crystals , 1978 .

[12]  J. Curro.  Computer simulation of multiple chain systems—the effect of density on the average chain dimensions , 1974 .

[13]  J. Bacri,et al.  Effets d'un champ magnétique sur l'atténuation et la vitesse des ondes ultrasonores dans un cristal liquide nématique , 1974 .

[14]  T. Funck,et al.  Ultrasonic measurements with milliliter liquid samples in the 0.5-100 MHz range. , 1973, The Review of scientific instruments.

[15]  G. Wetsel,et al.  Effects of Magnetic Field on Attenuation of Ultrasonic Waves in a Nematic Liquid Crystal , 1972 .

[16]  S. Letcher,et al.  Ultrasonic Determination of Anisotropic Shear and Bulk Viscosities in Nematic Liquid Crystals , 1971 .

[17]  F. Moon,et al.  Anisotropic Ultrasonic Wave Propagation in a Nematic Liquid Crystal Placed in a Magnetic Field , 1971 .

[18]  A. E. Lord,et al.  Anisotropic Ultrasonic Properties of a Nematic Liquid Crystal , 1970 .

[19]  B. Alberts,et al.  Rapid bacteriophage sedimentation in the presence of polyethylene glycol and its application to large-scale virus purification. , 1970, Virology.

[20]  R. Cerf,et al.  Absorption des ultrasons par les solutions de particules rigides , 1964 .