Thaw-melt method

Another procedure, known as the thaw melt method, is available for the construction of equilibrium diagrams it involves heating, instead of... 

Tetramethylene glycol, 250 Thaw-melt method, 28 Thaw point, 29... 

Many techniques have been used to characterize the physical nature of solid dispersions. These include thermal analysis (e.g., cooling-curve, thaw-melt, differential scanning calorimetry and X-ray diffraction, microscopic, spectroscopic, dissolution rate, and thermodynamic methods) Usually, a combination of two or more methods is required to obtain a complete picture of the solid dispersion system. 

Kobayashi et al. [16] studied the PVA gels by making high resolution solid-state NMR experiments with the CP/MAS and PST/MAS methods. The degree of polymerization and the degree of saponification of the PVA they employed were 1700 and 99.9%, respectively. The PVA gel was prepared from PVA/water solution (9% wt/wt) by four repeating freeze-thaw cycles (frozen at -20°C for 20 h, and then melted and sustained at 25°C for 4h). The PVA gel samples with different polymer concentrations were prepared by evaporation of water from them. 

A nonscientist may remain forever unaware of the boiling-point elevation phenomenon, but a careful observer living in a cold climate is familiar with freezing-point depression. Ice on frozen roads and sidewalks melts when sprinkled with salts such as NaCl or CaCl2. This method of thawing succeeds because it depresses the freezing point of water. 

For the studies preformed by this group on the anthracene + pyrene system (Rice et al., 2010), mixtures were prepared at various compositions by using a melt and quench-cool technique (Fu et al., 2010). Generally, the melting points and enthalpaes of fusion of these PAH binary mixtures were found to often actually be independent of mixture preparation techniques. The hquidus and thaw points were determined according to the method proposed by Potmder an Masson (Pounder and Masson, 1934). The thaw temperature is the temperature at which the first droplet of liquid appears in a mixture-containing capillary. The liquidus temperature is the maximum temperature at which both solid crystals and liquid are observed to coexist. Above this temperature, there is only liquid phase present. 

To thaw mount slices, one can either place a room temperature plate near a cold slice and allow the slice to melt onto the plate or use fine paint brushes to place a cold slice on a cold plate and warm both the plate and the slice together by removing them from the box into the room temperature air. The latter method has been shown to result in less peptide loss (25). 

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