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Abstract  

Scanning thermal microscopy (SThM) can measure thermal image with a nano-scale spatial resolution. However, there remains an issue in quantitative temperature measurement. We proposed an active temperature measurement method that provides a real temperature image by compensating a variation in contact thermal conductance. Performance of the active method was examined by a multi-function cantilever made with micro-fabrication process. Response test of the cantilever showed about 50 Hz cut off frequency for both passive and active method. Temperature measurement test indicated that sensitivity of heat flow detection was not enough to measure real temperature regardless of the thermal contact conductance. Imaging test demonstrated that the active method takes temperature image closer to real temperature distribution than the passive method.

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Abstract  

Modern thermal analysis, microcalorimetry and new emerging combined techniques which deliver calorimetric, microscopic and spectroscopic data offer a powerful analytical battery for the study of pharmaceuticals. These techniques are very useful in all steps of development of new drug products as well as methods for quality control in production. The characterization of raw materials enables to understand the relationships between polymorphs, solvates and hydrates and to choose the proper development of new drug products with very small amount of material in a very short time. Information on stability, purity is valuable for new entities as well as for marketed drug substances from different suppliers. Excipients which vary from single organic or inorganic entity to complexes matrixes or polymers need to be characterized and properly controlled. The thermodynamic phase-diagrams are the basis of the studies of drug-excipients interactions. They are very useful for the development of new delivery systems. A great number of new formulations need proper knowledge of the behaviour of the glass transition temperature of the components. Semi-liquid systems, interactions in aqueous media are also successfully studied by these techniques.

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Journal of Thermal Analysis and Calorimetry
Authors: J. Canotilho, R. Castro, M. Rosado, S. Nunes, M. Cruz, and J. Redinha

Abstract  

The growth of atenolol, pindolol and betaxolol hydrochloride from melt was investigated by differential scanning calorimetry (DSC) and polarized light thermal microscopy (PLTM). Phase transitions occurring on cooling and subsequent reheating runs performed between −160 °C and a temperature above the respective melting points were studied by DSC. The thermal cycles were also followed by PLTM. Details about the dynamic of the crystallization front taken from microscopic observations are given. An explanation of the results on the basis of molecular supramolecular recognition is advanced.

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Silicothermic reduction process in magnesium production

Thermal analysis and characterization of the slag

Journal of Thermal Analysis and Calorimetry
Authors: D. Minić, D. Manasijević, Jelena Ðokić, Dragana Živković, and Ž. Živković

Abstract  

In this paper there are presented the results of the characterization and thermal analysis of the slag from the magnesium plant ‘Bela Stena’, Serbia. The results of X-ray fluorescence analysis, scanning electron microscopy (SEM), optical microscopy (LOM) and X-ray diffraction (XRD) were used for chemical and mineralogical analysis of the solidified slag samples. Differential thermal analysis (DTA), thermo-gravimetric (TG) analysis and thermal microscopy results were used for determination of characteristic phase transformations. The solidified slag shows dicalcium silicate based structure. Magnesium is mostly present in the form of the following minerals: periclase, merwinite and melilite.

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Abstract  

In this study, the thermal behavior of butanediol isomers is investigated for temperatures ranging from 103 to 303 K using differential scanning calorimetry, complemented, when necessary, by polarized light thermal microscopy. The butanediol isomers display quite different thermal behaviors: for 1,2- and 1,3-isomers, glass transition is the only thermal event observed; for 1,4-butanediol, crystallization occurs on cooling even at a high scanning rate and no glass formation was detected; and for the 2,3-isomer, glass or crystal formation is dependent on the experimental conditions employed. The glass-forming ability of the isomers is correlated with data available on their molecular symmetry.

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Abstract  

The application of modulated temperature programs to thermomechanical analysis can be used to separate the reversible nature of thermal expansion from irreversible deformation arising from creep under the applied load or changes in dimensions due to relaxation of orientation. The effect of experimental variables and calibration are described. Modulated temperature TMA allows the time-dependent nature of thermal expansivity to be studied. Measurements made under compression afford a means of measuring the thermal expansivity of soft specimens independently of initial load. Application of these principles to scanning thermal microscopy leads to a novel method of generating image contrast based upon local changes thermal expansivity of a specimen.

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State Archives of Florence are reported. Parameters of their full denaturation endotherms, shrinkage temperature, T s , measured by thermal microscopy and damage scores are listed in Table 4 . Damage scores indicate a net ranking of parchments in three

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01979435 . 17. Vitez IM Newman AW . Thermal microscopy . In: Craig DQM , Reading M , editors. Thermal analysis

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