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Metal complexes of fenoterol drug

Preparation, spectroscopic, thermal, and biological activity characterization

Journal of Thermal Analysis and Calorimetry
Authors: M. Soliman, Gehad Mohamed, and Eman Mohamed

(II) transition metals with FEN drug molecule are prepared. The solid chelates are characterized using different physico-chemical methods like elemental analyses (C, H, N, and metal content), IR, 1 H NMR, magnetic moment, and thermal analyses (TG and DTA

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Abstract  

The adduct of Al(NO3)3·6CO(NH2)2 has been prepared and characterized by means of chemical analysis, IR spectroscopy, X-ray patterns and microscopy. A thermoanalytical study of Al(NO3)3·6CO(NH2)2 as well as urea, for comparison purposes, under conventional dynamic and quasi-isothermal—quasi-isobaric conditions in air has been carried out. It has been found that the adduct is thermally stable up to about 200°C, i.e. up to higher temperature than the decomposition temperature of the constituent compounds. The thermal decomposition mechanism of the adduct is complex, thus infrared spectroscopy and X-ray diffraction techniques have been used to determine the intermediate products. Aluminium oxide(III) is the final decomposition product.

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Transition metal(II) ions with dinegative tetradentate schiff base

Synthetic, thermal, spectroscopic and coordination aspects

Journal of Thermal Analysis and Calorimetry
Authors: H. Parekh, P. Panchal, and M. Patel

Abstract  

Some new coordination polymers of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II), obtained from the interaction of metal acetate with dipotassium salt of N,N’-di(carboxyethylidene)terephthalaldehydediimine (K2SB) are described. The products, which have been characterized by elemental analyses, magnetic measurements, thermogravimetric analyses, electronic and infrared spectral studies, have composition, [M(SB)(H2O)2]n. These colored coordination polymers are non-hygroscopic and quite stable at room temperature. On the basis of analytical data and IR studies, a 1:1 metal to ligand stoichiometry has been suggested to these coordination polymers. The IR studies have also revealed that ligands are coordinated to metal ion through carboxy oxygen and azomethine nitrogen. All the studies suggested tetradentate nature of the ligand with octahedral symmetry of the coordination polymers. All the coordination polymers are insoluble in acetone, ethanol, chloroform, methanol, benzene, DMF and DMSO. The thermal decomposition of the coordination polymers is studied and indicates that not only the coordinated water is lost but also that the decomposition of the ligand from the coordination polymers is necessary to interpret the successive mass loss.

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New approach to filled polymers

Mechanopolymerization on fillers

Journal of Thermal Analysis and Calorimetry
Authors: E. Gutman and A. Bobovitch

Abstract  

Mechanopolymerization of pentabromobenzyl (mono)acrylate (PBB-MA) on the surface of inorganic fillers Mg(OH)2 and CaCO3 was studied. The role of activated surface of fillers was investigated using DSC and FTIR. The influence of milling time and of the filler chemical content on polymerization starting temperature and polymerization enthalpy was studied using DSC. It was shown that an increase of the filler concentration leads to a higher maximum conversion degree. The correlation between conversion kinetics and polymerization enthalpy of the material notpolymerized during milling was shown.

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growth, single crystal XRD, FTIR, EDAX, UV, thermal analyses (TG–DTA), and NLO property of the grown crystal. Experimental Crystal growth The starting material LHMED (AR grade) procured from Sigma

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using thermal analyses (TA) measurements and EI mass spectral (MS) fragmentation at 70 eV. Also, molecular orbital (MO) calculations are performed using PM3 procedure, on the neutral molecule and charged molecular ion to investigate bond length, bond

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Journal of Thermal Analysis and Calorimetry
Authors: Francesca Caterina Izzo, Elisabetta Zendri, Guido Biscontin, and Eleonora Balliana

(normally the amount of sample ranges between 0.5 and 2 mg); furthermore, the method does not require any pre-treatment and gives useful information in relatively short time [ 9 , 11 , 13 ]. Unlike previous applications of thermal analyses on drying oils

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atmosphere at the heating rate of 20 °C/min) and the related DTA–TG curves are shown in Fig. 4 . Fig. 2 XRD patterns of the products obtained through thermal analyses of Mo + 2Si powders at different heating rates up

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Abstract  

The mixed zirconium, titanium, hafnium and first-row transition metal oxides (containing phosphorous oxide) were prepared using ion exchange method followed by calcinations at 1020 K during 12 h. The resulted mixed oxides were identified by XRPD method and studied their thermal behaviour by TG-DTA analysis. As a result of thermal analysis there were found one exothermic (with a peak at about 950 K), and one endothermic (with a peak at about 1300 K) processes, both without mass loss. The observation was valid for all investigated samples. The analysis of XRPD patterns of the investigated samples showed well-defined crystal phases characteristic of each oxide. The XRPD analysis also verified the phase transition of tetravalent metal oxides from orthorhombic to tetragonal, observed by DTA analysis.

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200 °C. Thermal analyses (TG and DTA) were carried out using a NETZSCH-STA 449 instrument, using Pt crucibles, in air, with a heating rate of 10 K min −1 . Tests were conducted on both type of precursors, resulted from the polycondensation

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