Effects of Long-chain Molecule Additives in Water on Vortex Streets

The rotation of the CH 3 groups round the single C—C bond in ethane is associated with a threshold energy of about 3000 gcal./gmol. or 2 x 10 -13 erg/mol. (Schäfer 1938; Kistiakowsky, Lacher and Strutt 1939). In an aliphatic CH 2 chain where the carbon atoms are linked together by single bonds the corresponding energy must be of the same order and is most likely rather smaller. Supposing we consider any particular C—C bond in the chain and treat the two parts at each side of this bond as rigid rotators, then their kinetic energy would be 2 x 1/2 kT which at room temperature amounts to about one-fifth of the threshold energy. It seems very likely under these circumstances that a chain molecule of say ten to twenty carbon atoms should already at room temperature show signs of distortion due to internal rotation. If this is true, then the previously observed increase of the crystal symmetry at the melting-point of paraffins (Müller 1930, 1932) and the corresponding changes of the polarization of long-chain ketones (Müller 1937, 1938) can no longer be ascribed entirely to a rotation of the molecule in the field of the surrounding molecules but must at least partly be due to this internal distortion. It is clear that a distortion of this type tends to destroy the anisotropy of the molecule and to give an apparent isotropy to the crystal. The present experiments were made in order to obtain an estimate of the magnitude of the distortion effect. It is found to be surprisingly large.

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Reaction Kinetics of a Long‐Chain Molecule. II. Arends' Solution

The Journal of Chemical Physics ◽

10.1063/1.1733661 ◽

1963 ◽

Vol 38 (2) ◽

pp. 325-326 ◽

Cited By ~ 63

Author(s):

Joseph B. Keller

Keyword(s):

Reaction Kinetics ◽

Chain Molecule ◽

Kinetics Of ◽

Long Chain

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Reversible multi-coloring reaction of spironaphtooxazine controlled by long-chain molecule

Journal of Photochemistry and Photobiology A Chemistry ◽

10.1016/j.jphotochem.2010.05.024 ◽

2010 ◽

Vol 213 (2-3) ◽

pp. 189-193 ◽

Cited By ~ 15

Author(s):

Kenji Kinashi ◽

Takashi Horiguchi ◽

Kyoji Tsutsui ◽

Kenji Ishida ◽

Yasukiyo Ueda

Keyword(s):

Chain Molecule ◽

Long Chain

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Vibrations of Finite Linear Chains of Molecules

Australian Journal of Physics ◽

10.1071/ph780313 ◽

1978 ◽

Vol 31 (4) ◽

pp. 313

Author(s):

J Mahany ◽

BB Deo

Keyword(s):

Infinite Chain ◽

Chain Molecule ◽

Vibration Frequencies ◽

Finite Chain ◽

Linear Chains ◽

Matrix Partitioning ◽

Finite Linear ◽

Long Chain ◽

Partitioning Technique ◽

Secular Determinant

Szigeti's (1961) method for obtaining the vibration frequencies of a finite chain (representing a long-chain molecule) from those of an associated infinite chain is analysed by a matrix partitioning technique. It is shown that this method has the advantage of reducing the dimensionality of the secular determinant. The approach is illustrated by an example.

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Mechanical Properties of Long Chain Molecule Liquids at Ultrasonic Frequencies

Physical Review ◽

10.1103/physrev.73.1074 ◽

1948 ◽

Vol 73 (9) ◽

pp. 1074-1091 ◽

Cited By ~ 57

Author(s):

W. P. Mason ◽

W. O. Baker ◽

H. J. Mcskimin ◽

J. H. Heiss

Keyword(s):

Mechanical Properties ◽

Chain Molecule ◽

Long Chain

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THE EFFECT OF TEMPERATURE AND MIXED-SOLVENT COMPOSITION ON THE INTRINSIC VISCOSITY OF GR–S

Canadian Journal of Research ◽

10.1139/cjr48b-024 ◽

1948 ◽

Vol 26b (2) ◽

pp. 230-247 ◽

Cited By ~ 1

Author(s):

L. H. Cragg ◽

T. M. Rogers

Keyword(s):

Intrinsic Viscosity ◽

Strong Evidence ◽

Mixed Solvent ◽

Solvent Composition ◽

Temperature Measurements ◽

Effect Of Temperature ◽

Chain Molecule ◽

First Approximation ◽

Long Chain

The intrinsic viscosity of a sample of GR–S has been measured, at temperatures ranging from 0° to 65 °C., in several solvents made progressively 'poorer' (to the point of precipitation) by the addition of nonsolvent. The results afford strong evidence in support of the theory (Flory; Alfrey, Bartovics, and Mark) that intrinsic viscosity is very sensitive to the shape assumed by a flexible long-chain molecule in solution and that this shape varies with the nature of the solvent and with the temperature. Measurements with various systems of the type GR–S–solvent–nonsolvent indicate that the intrinsic viscosity at the precipitation point is the same with different nonsolvents and, to a first approximation, with different solvents. This intrinsic viscosity is, moreover, independent of temperature.

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