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large change in the mass loss, and we repeated isothermal measurements with the temperature step of 1 °C, sample mass was 26.601 mg. X-ray powder diffraction Variable-temperature X-ray powder diffraction data for

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heated at 900 °C for 10 h. After a new rubbing it was still heated at 1000 °C for 20 h. The phase equilibria in the system Rb 3 PO 4 –Ba 3 (PO 4 ) 2 were investigated using thermoanalytical methods, X-ray powder diffraction, ICP, and FT

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Journal of Thermal Analysis and Calorimetry
Authors: Marieta Muresan-Pop, Irina Kacsó, Carmen Tripon, Z. Moldovan, Gh Borodi, S. Simon, and I. Bratu

, until a dried compound was obtained. X-ray powder diffraction X-ray powder diffraction pattern was obtained using Bruker D8 Advance diffractometer, sealed Cu tube λ = 1.5406 Å equipped with an incident beam Ge 111

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Journal of Thermal Analysis and Calorimetry
Authors: Anna Kohutová, Pavla Honcová, Ladislav Svoboda, Petr Bezdička, and Monika Maříková

, composition and specific surface area. Analytical methods, such as electron microscopy, infrared microscopy with Fourier transformation, Raman spectroscopy, X-ray powder diffraction (XRD) and thermal analysis are generally used for qualitative and

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Abstract  

Lanthanum(III) tris-tartrato lanthanate(III) decahydrate, La[La(C4H4O6)3]10H2O has been synthesized and characterized by elemental analysis, IR, electronic spectral and X-ray powder diffraction studies. Thermal studies (TG, DTG and DTA) in air showed a complex decomposition pattern with the generation of an anhydrous species at ~170C. The end product was found to be mainly a mixture of La2O3 and carbides at ~970C through the formation of several intermediates at different temperature. The residual product in DSC study in nitrogen at 670C is assumed to be a similar mixture generated at 500C in TG in air. Kinetic parameters, such as, E*, ΔH, ΔS, etc. obtained from DSC are discussed. IR and X-ray powder diffraction studies identified some of the decomposition products. The tentative mechanism for the thermal decomposition in air of the compound is proposed.

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The formation of substitutional solid solutions of the isostructural oxyhydroxides α-FeOOH-α-AlOOH (goethite-diaspore and γ-FeOOH-γ-AlOOH (lepidocrocite-boehmite) was investigated by X-ray powder diffraction technique and by thermal analysis.

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Journal of Thermal Analysis and Calorimetry
Authors: P. Espeau, B. Nicolaï, R. Céolin, M. Perrin, L. Zaske, J. Giovannini, and F. Leveiller

Abstract  

Investigation into the thermal behavior of orthorhombic Forms I and II of spironolactone, by means of differential scanning calorimetry and high-resolution X-ray powder diffraction, showed that Form I melts then recrystallizes into Form II at 373–393 K, i.e. in the temperature range within which high resolution X-ray powder diffration showed that Form I transforms into Form II. Refinements of the lattice parameters of the two forms indicated that Form I is denser than Form II in the range from 298 K up to the temperature at which it melts.

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Abstract  

Captopril (CAP) was the first commercially available angiotensine-converting enzyme (ACE) inhibitor. In the anti-hypertensive therapy is considered the selected drug has to be therapeutically effective together with reduced toxicity. CAP is an antihypertensive drug currently being administered in tablet form. In order to investigate the possible interactions between CAP and excipients in tablets formulations, differential scanning calorimetry (DSC) and thermogravimetric (TG) analysis completed by X-ray powder diffraction (XRPD) and Fourier transform infrared spectroscopy (FTIR) were used for compatibility studies. A possible drug-excipient interaction was observed with magnesium stearate by DSC technique.

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Abstract  

Differential scanning calorimetry (DSC) data showed that the crystallinity of poly(ethylene glycol) 6000 in solid dispersions containing and diazepam or temazepam only slightly increased upon aging and that the twice folded modification of the polymer unfolded into the once folded modification during aging, while the once folded modification did not unfold. This unfolding was found to be time and temperature dependent. X-ray powder diffraction data revealed that the drug crystallinity in the solid dispersions slightly increased upon aging. The dissolution profiles of aged and non-aged solid dispersions were comparable. It was concluded that polymer unfolding did not have an impact on the pharmaceutical performance of the investigated dispersions.

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