Low-melting fraction

The submitters report that partial evaporation of the mother liquors gives additional small quantities of low-melting fractions from which additional pure material may be obtained by further crystallizations. In contrast, the checkers obtained nearly one-half the yield in a second crop which had essentially the same melting point as the first crop. This somewhat different behavior may result from a difference in solvent characteristics of different samples of petroleum ether. 

Once formed by whatever mechanism, carbonate melts will wet an olivine and pyroxene matrix, so the melt will be interconnected and mobile at extremely low melt fraction (Hunter and McKenzie, 1989 Minarik and Watson, 1995), rendering it a potential metasomatic agent. 

Minarik W. G. and Watson E. B. (1995) Interconnectivity of carbonate melts at low melt fraction. Earth Planet. Sci. Lett. 133, 423-437. 

Fig. 2. Small-angle X-ray diffraction recordings of form V of cocoa butter (solid line) and of its high-melting fraction (HMF) (dashed line) insert shows form V of cocoa butter on an enlarged y scale and its low-melting fraction (LMF) which do not display the line at 44.4A. Both HMF and LMF fractions are obtained by dry fractionation of BC (4).

Low-melting fractions can be recrystallized from hot water (7 ml./g.) to remove any unreacted ester. In a typical experiment three fractions were obtained by cooling to 40, 30, and 5°. These melted with decomposition at 166 to 167, 167, and 163 to 164°, respectively. 

Figure 3.1 DSC melting and crystallisation thermograms of palm oil. For melting thermogram, sample was cooled to — 30°C at rate of 40°C/min, held for 10 mins and heated to 80°C at 5°C/min for cooling thermogram, sample was melted to 80°C and cooled to —30°C at 5°C/min. Lm low melting fraction, Hm high melting fraction.

The coolativily of a bundle with pins having a low melt fraction in case of a rupture and fuel ejection from one pin RB3 test to be performed in SCARABEE. 

Fat is separated into high and low melting fractions by reducing reaction temperature. 

A schematic diagram outlining the Fuji oil process is shown in Figure 12.7. The composition of the dominant triacylglycerols (POP, POS and SOS) in the low melting fraction obtained from such a process were 15.5%, 38.2% and 22.6%, respectively, compared to those of cocoa butter 13.5%, 34.8% and 23.2% (Sawamura, 1988). The solid content. 

Fractionated butterfat. The butter is separated by fractional crystallization into high- and low-melting fractions, and is utilized for various purposes (e. g. consistency improvement of whipping creams and butters). 

Confusion about the stereochemistry of the calix[4]- and [8]arenes already played a role in the work of Comforth et al. mentioned above. They attributed the different physical properties of the high and low melting fractions (HBC and LBC, respectively) to different conformers of the cyclic tetramer (a calix[4]arene), because on the basis of their space filling molecular models they believed that the phenolic OH groups could not rotate through the annulus. And this could give rise to four different rotational diastereoisomers (Fig. 1.5). 

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