Freezing-point frequency

Fractional crystallization, 413 Freezing point lowering, 325, 393 Freon, 362 Frequency of light, 246 relation to wave length, 251 Fructose, 423 Fumaric acid, 428 properties, 308 structure, 316... 

Second, the composite hat-curved-harmonic oscillator model provides a good perspective for a spectroscopic investigation of ice I (more precisely, of ice Ih), which is formed at rather low pressure near the freezing point (0°C). The molecular structure of ice I evidently resembles the water structure. Correspondingly, well-known experimental data show a similarity of the FIR spectra (unlike the low-frequency spectra) recorded in liquid water and in ice Ih. This similarity suggests an idea that rotational mobility does not differ much in... 

The decrease in the freezing point of a solvent caused by the presence of a solute. Frequency... 

The same apparatus was used to measure the kinetics of emulsion crystallization under shear. McClements and co-workers (20) showed that supercooled liquid n-hexadecane droplets crystallize more rapidly when a population of solid n-hexa-decane droplets are present. They hypothesized that a collision between a solid and liquid droplet could be sufficient to act as a nucleation event in the liquid. The frequency of collisions increases with the intensity of applied shear field, and hence shearing should increase the crystallization rate. A 50 50 mixture of solid and liquid n-hexadecane emulsion droplets was stored at 6 -0.01 °C in a water bath (i.e., between the melting points and freezing points of emulsified n-hexadecane). A constant shear rate (0-200 s ) was applied to the emulsion in the shear cell, and ultrasonic velocities were determined as a function of time. The change in speed of sound was used to calculate the percentage solids in the system (Fig. 7). Surprisingly, there was no clear effect of increased shear rate. This could either be because increase in collision rate was relatively modest for the small particles used (in the order of 30% at the fastest rate) or because the time the interacting droplets remain in proximity is not affected by the applied shear. 

Freezing point. The temperature at which the solid and liquid phases of a substance coexist at equilibrium. (11.8) Frequency. The number of waves that pass through a particular point per unit time. (7.1)... 

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