Showing papers in "Thermochimica Acta in 1995"

TL;DR: In this paper, the authors present a review of the use of thermal analysis for the analysis of polymorphism and pseudo-polymorphism in drug substances and excipients, including solvates and impurities.

TL;DR: In this paper, the applicability of the Johnson-Mehl-Avrami equation for non-isothermal crystallization kinetics has been investigated, and it has been shown that it has limited applicability for the nonisothermal transformations involving nucleation and growth.

TL;DR: In this paper, two series of NiO Al 2 O 3 catalysts with various metal loadings were prepared by incipientwetness impregnation and coprecipitation methods.

TL;DR: In this paper, a spectrum of thermal and XRD analysis results from ancient, Byzantine, post-Byzantine and later historic mortars from Greece is presented and relevant information concerning the characterization of traditional mortars is validated.

TL;DR: In this article, two different methods for the evaluation of the measured data are compared theoretically for the case of simple time-dependent processes, for the glass transition process and the linear response theory, and the theoretical basis and possibilities of interpretation of both evaluation methods are investigated.

TL;DR: In this paper, the kinetics of the thermal decomposition of cellulose in nitrogen were studied using dynamic TG at heating rates between 5 and 50 K min −1, and the most widely used models found in the literature which are usually applied in isothermal conditions were tested.

TL;DR: In this article, a new evaluation method for modulated temperature-DSC measurements based on linear response theory is presented, which yields a complex heat capacity with a real part (storage heat capacity) and an imaginary part (loss heat capacity).

TL;DR: In this article, the extrapolation of a set of thermoanalytical (TA) curves to infinite temperature is proposed as a possible method to calculate the kinetic parameters of solid-state reactions from the TA curves without assuming a constant heating rate.

TL;DR: In this paper, different cases in which using DSC allows us to obtain more information about the internal structure of microspheres, especially concerning the nature of the interaction between the polymer matrix and the encapsulated drug.

TL;DR: Modulated differential scanning calorimetry (MDSC) as mentioned in this paper can measure the glass transition temperature largely independent of the thermal history (and the heating or cooling rates), but dependent on the modulation frequency.

TL;DR: In this paper, the fundamental kinetic equations for the non-isothermal reactions are reexamined in an attempt to increase the reliability of the kinetic parameters obtained for solid state reactions, and it is suggested that reliable kinetic parameters are obtained in terms of kinetic equations with non-integral kinetic exponents.

TL;DR: In this article, the authors used modulated differential scanning calorimetry (MDSC) to study simultaneously the evolution of heat flow and heat capacity for the isothermal cure of thermosetting systems.

TL;DR: In this article, the decomposition of ammonium thiomolybdates was investigated using thermogravimetric analysis (TGA), either in pure N 2 or in 10% H 2 in N 2, and temperature-programmed reduction.

TL;DR: This paper reviews investigations of the phase transition behaviour of single component phospholipid systems, bilayers having mixtures ofospholipids and bilayers containing phospholIPid-cholesterol mixtures and the use of DSC studies of drug-liposome interactions as models of drug

TL;DR: Using thermogravimetry/Fourier transform infrared (TG/FTIR) coupling, qualitative and quantitative analyses of the effluents which appear during a thermal cycle were performed in this paper.

TL;DR: In this article, a technique for determining vaporization enthalpies Δg1Hm(298 K) of organic compounds by high resolution gas chromatography was described, and the best results were obtained when the reference compounds are structurally similar and in the same chemical family.

TL;DR: The ability to alter and control such properties as particle shape, particle size and size distribution, bulk density, porosity, moisture content, flowability, stability, dispersability and friability has led to the increasing use over the last fifty years, of spray drying methods in the manufacture of pharmaceutical dosage forms.

TL;DR: In this paper, the influence of carbon dioxide on the thermal decomposition kinetics of calcium carbonate is studied and it is shown that it is possible to obtain meaningful and reliable kinetic parameters from isothermal and non-isothermal data provided that the pressure correction term is included in the kinetic equation.

TL;DR: In this article, the influence of cooling rate during glass preparation on Tg, heating rate, and annealing on the glassy state are reviewed and discussed with reference to the recently published original research papers.

TL;DR: In this paper, the authors examined DTA, TGA and XRD results from byzantine and medieval ceramics and information derived on ceramic technologies concerning raw materials and production conditions is validated by SEM observations concerning the extent of vitrification.

TL;DR: In this paper, the effect of accelerator content on the curing reaction of an epoxy resin based on diglycidyl ether of bisphenol A (DGEBA) with methyl-tetrahydrophthalic anhydride was studied.

TL;DR: In this paper, a basic approach is offered by granulometric analysis, allowing separation of the mortar into its components, in which the finer fraction is richer in binder, and some analyses on this fraction (μ m) were performed to define the nature and quantity of the binder in the mortar.

TL;DR: In this article, the uses, properties and structure of polyethylene glycols are discussed, with particular emphasis on pharmaceutical considerations, and applications of thermal techniques in the characterisation of these materials in the solid or molten states and in aqueous solution are described.

TL;DR: In this article, the state of water confined in the pores of commercial silica gels has been investigated as a function of the water content using differential scanning calorimetry (DSC).

TL;DR: In this article, the thermal decomposition of sodium bicarbonate (NaHCO3) was studied under different atmospheres (dry nitrogen, air, and carbon dioxide), with various heating rates in order to characterize the substance.

TL;DR: In this paper, a relationship between the peak temperature and height in derivative thermogravimetry (DTG) curves was explored to seek their specific combination for addressing the uniqueness of a thermal reaction.

TL;DR: In this article, a positive correlation was found between the percentage humidity, the total heat evolution and the microbial growth rate constant, which is calculated by the microcalorimetric method.

TL;DR: In this paper, a microcalorimetric study of the oxidation of Lascorbic acid in solution was carried out under varying conditions of pH, oxygen concentration, ascorbic acid concentration, temperature, addition of ethylene-diaminetetraacetic acid (EDTA) and addition of a radical scavenger.

TL;DR: In this paper, it was shown that low temperature calorimetry is an efficient tool for scanning the distribution of the atomic vibrational states in real substances, and that the fractal dimension and Poisson's ratio in the elastic-isotropic multifractal model are related by a simple interdependence.

TL;DR: In this paper, the main dehydration of the calcium sulphate dehydrate part of synthetic gypsum occurs between 95 and 170°C (heating rate 5°C min−1) and seems to proceed via a process with an activation energy of 392 ± 100 kJ mol−1 for α-values between 0 and 0.1.