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Abstract  

Five poorly soluble drugs namely hydrochlorothiazide, menadione, propylthiouracil, quinine sulfate and sulfamerazine were used to evaluate the ability of an index (I c) based on the van't Hoff equation to predict the eutectic composition at a higher heating rate than previously published. The term I c is a dimensionless index which has been defined in the literature and is used to predict eutectic composition. This current work uses this study to determine if the correlation holds true at the higher heating rate of 10C min-1. The maximum deviation was observed for quinine sulfate, for which the predicted eutectic composition was 10% lower than what was observed with the DSC. It can be concluded that the Index developed here has a good correlation with the experimentally determined eutectic composition.

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Abstract  

The effect of oxygen concentration on the melting of this eutectic was investigated by DSC. In the deoxygenized solution, an endothermic peak attributed to the eutectic transition was observed in the course of heating, and its peak temperature is around −21.5°C. Another endothermic peak appeared at lower temperature in the presence of oxygen. As the oxygen content in the solution increases, the temperature of this peak is shifted to lower temperature. The transition at the lower temperature are associated with the melting of eutectic carrying oxygen. The same results are given in the NMR data.

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Abstract  

When the DSC analysis of different samples of terpin hydrate is carried out, a non identified small endotherm is observed at about 100°C, just before the melting endotherm. This phenomenon is detected whatever the experimental conditions are.After some trials, this endotherm was identified as an eutectic formed with terpin hydrate and desolvated terpin (17/83).The importance of the experimental conditions is preponderant. In an open pan, the desolvation occurs and the melting endotherm of the anhydrous form can be observed at 105°C. In a closed pan, no desolvation is detected and the melting endotherm at 120°C is that of the terpin hydrate.The eutectic exhibits a good compression ability and a fast dissolution. Its stability is correct. Its use in therapeutic tablets can be envisaged.The eutectic structure could be, more generally, favourable to compression owing to the isotropic texture of this particular solid state.

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Thermal and physico-chemical studies on binary organic eutectic systems

4-Aminoacetophenone with benzoin and 4-nitrophenol

Journal of Thermal Analysis and Calorimetry
Authors: Shiva Kant, U. S. Rai, and R. N. Rai

Introduction The eutectic alloys are found competent materials for the supersonic aircraft, space vehicles, high pressure tanks, thermoelectric devices (safety plugs in fire detection apparatus, alarm signals, etc.), and

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the study in detail. In this article, we report the phase diagram study, thermal study of the pure compounds and the eutectics such as heat of fusion, Jackson’s roughness parameter, excess thermodynamic functions, and microstructural study. However

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transformation temperature, transparency, wider choice of materials, and minimized convection effects are the special features which have prompted a number of research groups to work on binary organic eutectics, monotectics, and molecular complexes [ 5 – 9 ]. To

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Introduction The field of phase equilibria in materials science has become extensive, and a number of review articles have appeared and reported in the literature [ 1 – 6 ] but the nature and liquidus structure of eutectic

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been responsible for the rejection of 70% of the potentially active drugs. Eutectic mixtures have played a key role in improving the absorption of many compounds by increasing their solubility and dissolution properties [ 1 ]. A eutectic is a

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performance high energy explosive, and it could form eutectic liquid carrier. The energy and liquefy temperature for the eutectic mixtures could be adjusted yet and the different performance required casting explosive ingredients also could be confected. The

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systems [ 1 – 3 ]. The organic eutectics, monotectics and addition compounds, which could be considered as organic analogs of metallic eutectics, monotectics and intermetallic compounds [ 4 – 6 ], have gained potential importance due to low transformation

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