Temperature- and moisture-dependent phase changes in crystal forms of barbituric acid

Thiobarbiturate and barbiturate salts of pefloxacin drug: Growth, structure, thermal stability and IR-spectra

“…1.87 [10]) also resulting from the presence of two methylene hydrogen atoms. The existence of three polymorphs of anhydrous H2ba and deihydrate [11][12][13], and six polymorphs of anhydrous thiobarbituric acid and hydrate [14] make these molecules interesting from the viewpoint of crystal engineering. They can be used as a building block to construct the supramolecular assemblies with distinctive properties.…”

Effect of Experimental and Sample Factors on Dehydration Kinetics of Mildronate Dihydrate: Mechanism of Dehydration and Determination of Kinetic Parameters

“…Typically hydrate stability is evaluated by characterizing the dehydration conditions and observed phase changes. The most common techniques for studying dehydration are powder X-ray diffraction (PXRD), [3][4][5][6][7] thermal analysis, 3,5,6,[8][9][10][11][12][13][14] spectroscopic methods, 8,12,[15][16][17] and particle morphology and particle size characterization of the original and dehydrated products. [18][19][20] By using these methods, it is possible to determine the dehydration conditions and understand the behavior of hydrate upon dehydration.…”

Effect of thermal stabilizers composed of zinc barbiturate and calcium stearate for rigid poly(vinyl chloride)

“…3. A broad double-band (3564 and 3543 cm À1 ) and a single-band at 3478 cm À1 corresponding to the different hydroxyl in the enoltautomer structure of barbituric acid [26] given in Fig. 4 can be easily found in Fig.…”

“…3 (Fig. 4, ketotautomer) around 1750 cm À1 [26] (i.e. 1768, 1758, 1745 and 1716 cm À1 ) are replaced by a single sharp peak at 1711 cm À1 , and two intense peaks appeared at 1591 and 1262 cm À1 corresponding to carbonyl and carbon-oxygen (CeO) bonds in ZnL 2 , respectively.…”