Search Results
Abstract
The physicochemical properties of theophylline hydrate and anhydrous polymorphic forms I and II were evaluated using crystallographic and calorimetric method. This study has been carried out with the following techniques: differential scanning calorimetry (DSC), thermogravimetric analysis (TG) and X-ray diffractometry. The X-ray patterns on powder for investigated compounds are presented.
Abstract
The TG and DTA curves and diffractograms of powdered CeO2 samples irradiated with a CO2 laser beam with powers of 0.41–1.39 kW/cm2 are presented. The laser treatment induced structural changes and probably generation of a metastable phase. X-ray diffraction coupled with thermal analysis was used to establish the structural modifications in the irradiated samples after heating.
for optical resolution by preferential crystallization [ 15 ]. Moreover, it is known that BupiHCl is polymorphic [ 16 ]. Temperature-resolved X-ray experiments performed by Giron et al. demonstrated the existence of two anhydrous forms. The
Abstract
Cellulose was chemically modified with SOCl2 to obtain chlorodeoxycellulose, followed by a reaction that gave bonded ethylene-1,2-diamine (en), producing 6-(2′-aminoethylamino)-6-deoxycellulose. The reactions were carried out without the presence of solvent, in water or in N,N′-dimethylformamide, in which the highest amount of amino compound was incorporated onto the biopolymer backbone. The X-ray diffraction patterns for the chlorodeoxycellulose indicate new crystallinities that result from hydrogen bonds established through bonded chorine atoms and the remaining hydroxyl groups, while all the aminodeoxycelluloses were amorphous compounds. Thermal stabilities, for all aminated celluloses gave lower final mass losses than for the chlorinated biopolymer, whose value is lower than unmodified cellulose.
Somosy, Z., Thuróczy, G., Köteles, G. J., Kovács, J. (1994) Effects of modulated microwave and X-ray irradiation on the activity and distribution of Ca 2+ -ATPase in small intestine epithelial cells. Scanning Microscopy 8 , 613
Abstract
X-ray fluorescence analysis study of 44 archaeological pottery samples collected from Tell Jendares site north-west of Syria has been carried out. Four samples of the total previous investigated samples were obtained from the kiln found on Tell Jendares site. Seventeen different chemical elements were determined. The XRF results have been processed using two multivariate statistical cluster and factor analysis methods in order to determine the similarities and correlation between the selected samples based on their elemental composition. The methodology successfully separates the samples where three distinct chemical groups were discerned.
Abstract
Polymorphism of trilaurin mixed with 4% of cholesterol was studied with a setup coupling calorimetry and phase characterisation by in-situ X-ray diffraction (Microcalix). Four polymorphic forms were identified. Monotropic and enantiotropic transitions were identified from the reconstruction of Gibbs free energy diagram which allows the control of trilaurin polymorphism.
Intensive Care Med 2004 30 276 281 Greenbaum DM, Marschall KE: The value of routine daily chest X-rays
detector for low-dose X-ray imaging. Nuclear Instruments and Methods in Physics Research A, 2005, 536 , 52–60. Gravel P. Evaluation of a full-scale gas microstrip detector for low-dose X-ray
product and its degradation behavior in vitro and/or in vivo. As physico-chemical characterization techniques, scientists have been using a series of very valuable methods: spectroscopy, microscopy, X-ray techniques and so on. In our previous
