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Solid–liquid phase diagrams of binary mixtures

Acetylsalicylic acid(1) + E(2) (E = salicylic acid, polyethylene glycol 4000, d-mannitol)

Journal of Thermal Analysis and Calorimetry
Authors: Luigi Campanella, Valentina Micieli, Mauro Tomassetti, and Stefano Vecchio

Abstract  

This study reports the investigation of three binary mixtures represented by acetylsalicylic acid (ASA) with its most important degradation product, salicylic acid (SA), and two of the most commonly used excipients (polyethylene glycol 4000 (PEG-4000) and d-mannitol (MA)). The liquidus and solidus equilibrium temperatures determined by DSC for pure components and solid binary mixtures at a fixed composition (mass fraction of ASA, w) were used to construct the corresponding solid–liquid phase diagrams. On the basis of the DSC results, the binary mixtures ASA/SA and ASA/PEG exhibit eutectic behavior (T eu = 155.0 ± 0.5 °C, w eu = 0.55 ± 0.02 and T eu = 53.3 ± 0.5 °C, w eu = 0.32  ± 0.01 ), respectively), while the binary mixture ASA/MA revealed the presence of a monotectic with a mean melting temperature of 162.2 °C in the range 0.2 < w 1 < 0.8. The composition of the two eutectics formed was confirmed by the related Tamman triangles. Finally, the liquidus curves of ASA/SA and ASA/PEG mixtures were also successfully predicted providing suitable polynomial (second-order) fitting equations.

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ternary phase diagrams for the apparent fusion heat with the composition (ternary H – X phase diagrams) have been constructed. The ternary T – X phase diagrams (the temperature dependence on composition) for the two ternary systems have been

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Journal of Thermal Analysis and Calorimetry
Authors: S. Wacharine, D. Hellali, H. Zamali, J. Rogez, and M. Jemal

and their phase diagrams contributes to give information for their use. Complete phase diagram of the CsNO 3 –RbNO 3 system has never been reported in literature. Wallerant [ 1 ], Blidin [ 2 ] ( Fig. 1 a) studied only the liquidus in a range

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Journal of Thermal Analysis and Calorimetry
Authors: Alexandre Berche, Pierre Benigni, Jacques Rogez, and Marie-Christine Record

composition for these alloys and the optimization of their processing conditions both rely on the good knowledge of the corresponding ternary phase diagrams and of its constitutive binaries. Two distinct routes can be used to establish phase diagrams

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Journal of Thermal Analysis and Calorimetry
Authors: Ljubiša Balanović, Dragan Manasijević, Dragana Živković, Aleksandra Mitovski, Nadežda Talijan, Duško Minić, and Živan Živković

technologies, e.g. die-attach and ball grid array (BGA) solder spheres, chip scale package (CSP) and multi-chip modelling (MCM). Knowledge about the phase diagram and the thermodynamic properties of the studied soldering system is required to predict

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determine the eutectic composition and temperature for the system fenofibrate–acetylsalicylic acid, through the construction of the phase diagram based on the results of DSC heating experiments, as well as to investigate the solubility and dissolution rate

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Journal of Thermal Analysis and Calorimetry
Authors: Bedřich Smetana, Simona Zlá, Aleš Kroupa, Monika Žaludová, Jaromír Drápala, Rostislav Burkovič, and Daniel Petlák

investigation is focused on the area close to the monovariant line in the phase diagram of Sn–Zn–Al ternary system ( Fig. 1 ). As this region of the Sn–Zn–Al phase diagram still deserves a lot of attention [ 3 – 11 ], the temperatures of phase transitions were

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Journal of Thermal Analysis and Calorimetry
Authors: Maria Kuhnert-Brandstätter and A. Burger

Abstract  

The stearic acid-urea binary system exhibits an unusual phase diagram, which, on the one hand, indicates an incongruently melting inclusion compound and on the other hand a miscibility gap in the liquid phases. The peritectic point lies near the melting point of urea and the unstable congruent melting point of the inclusion compound coincides with the melting point of urea. In addition to the processing of the phase diagram, the pure inclusion compound was prepared and its DSC curve, FTIR spectrum and X-ray diffractogram were recorded.

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Journal of Thermal Analysis and Calorimetry
Authors: Edward Krzyżak, Alina Wojakowska, Andrzej Wojakowski, and Marek Wołcyrz

Abstract  

Phase diagram for the system CuBr–LiBr was determined by differential scanning calorimetry and X-ray powder diffraction. The system exhibits a significant solid solubility of the components, especially LiBr in the respective polymorphic modifications of CuBr. Another feature of the system CuBr–LiBr is the occurrence of five invariant three-phase equilibria, which have been assigned to one eutectic (684 K), one peritectoid (668 K), and three eutectoids (679, 645, and 521 K). From the experimental results, formation of a compound LiCuBr2, at 521 K is discerned.

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Phase diagrams of perhydrotriphenylene and aromatic compounds

I. Trans stylbene and 4H-cyclopenta[2,1-b∶3,4-b′] dithiophene

Journal of Thermal Analysis and Calorimetry
Authors: G. Di Silvestro, Cui Ming Yuan, A. Terragni, Elisabetta Brenna, and Manuela Gilberti

Perhydrotriphenylene (PHTP) forms channel-like adducts with molecules of different size and molecular weight. In the crystal structure of the adduct the included long sequences of molecules are separated from each other by the channel walls. The optical properties of the included molecules differ from those of the bulk molecules. The phase diagram of mixtures of PHTP and trans stylbene and 4H-cyclopenta [2,1-b∶3,4-b′] dithiophene (CPDT) were determined by DSC experiments. Ideality in the liquid phase was observed only in the PHTP/CPDT system.

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