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Dehydration Behavior (dehydration + behavior)
Selected AbstractsHydrolysis of ,-Tricalcium Phosphate in Simulated Body Fluid and Dehydration Behavior During the Drying ProcessJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2007Xiang Wei The hydrolysis of ,-tricalcium phosphate (,-TCP) in a simulated body fluid (SBF) at 37°C was investigated. The hydration rate was found to be slower in SBF than that in deionized water. The concentration of ions in SBF was monitored by ICP. The hydrolysis product, which was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infra red, and X-ray photoelectron spectroscopy, was determined to be carbonate-containing, calcium-deficient hydroxyapatite (CO3,CDHAp) with Mg2+, Na+, and Cl, impurities similar to the biological apatite. An amorphous layer on the ,-TCP surface was found to be the precursor of the apatite phase, which may either form crystalline apatite or may decompose back to ,-TCP at a lower temperature. [source] Synthesis, Structure, and Magnetism of a Highly Thermally Stable Microporous Metal Organodiphosphonate with Reversible Dehydration/Rehydration BehaviorEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2006Hua Li Abstract The synthesis and crystal structure of a novel organic,inorganic hybrid material Co2(H2O)2[O3PCH2(C6H4)CH2PO3] is described. It crystallizes in the orthorhombic space group Pca2(1) [a = 9.6214(19), b = 5.6855(11), c = 21.725(4) Å, V = 1188.4(4) Å3], which consists of two-dimensional cobalt,oxygen inorganic layers pillared by p -xylylenediphosphonateto form a three-dimensional framework, which has 10.850,×,5.687 Å channels running along the b -axis. The material is exceptionally stable, even when heated up to 500 °C in air. More interestingly, the framework components display a reversible dehydration/rehydration behavior. There is an antiferromagnetic interaction between the cobalt ions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Dehydration studies using a novel multichamber microscale fluid bed dryer with in-line near-infrared measurementJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 10 2003Eetu Räsänen Abstract The purpose of this research was to study the effect of two process parameters (temperature and moisture content) on dehydration behavior of different materials using a novel multichamber microscale fluid bed dryer with a process air control unit and in-line near-infrared (NIR) spectroscopy. The materials studied were disodium hydrogen phosphates with three different levels of hydrate water and wet theophylline granules. Measured process parameters of fluid bed drying were logged, including in-line NIR signals. Off-line analyses consisted of X-ray powder diffraction patterns, Fourier transform NIR spectra and moisture contents of studied materials. During fluid bed drying, the stepwise dehydration of materials was observed by the water content difference of inlet and outlet air, the pressure difference over the bed, and the in-line NIR spectroscopy. The off-line analysis confirmed the state of solid materials. The temperature and the moisture content of the process air were demonstrated to be significant factors for the solid-state stability of theophylline. The presented setup is a material and cost-saving approach for studying the influence of different process parameters on dehydration behavior during pharmaceutical processing. © 2003 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 92:2074,2081, 2003 [source] Synthesis, Structure, and Magnetism of a Highly Thermally Stable Microporous Metal Organodiphosphonate with Reversible Dehydration/Rehydration BehaviorEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2006Hua Li Abstract The synthesis and crystal structure of a novel organic,inorganic hybrid material Co2(H2O)2[O3PCH2(C6H4)CH2PO3] is described. It crystallizes in the orthorhombic space group Pca2(1) [a = 9.6214(19), b = 5.6855(11), c = 21.725(4) Å, V = 1188.4(4) Å3], which consists of two-dimensional cobalt,oxygen inorganic layers pillared by p -xylylenediphosphonateto form a three-dimensional framework, which has 10.850,×,5.687 Å channels running along the b -axis. The material is exceptionally stable, even when heated up to 500 °C in air. More interestingly, the framework components display a reversible dehydration/rehydration behavior. There is an antiferromagnetic interaction between the cobalt ions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] | ||||||||||