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Abstract  

Physico-chemical properties of 4-chloro-2-nitrobenzoates of Co(II), Ni(II), and Cu(II) were studied. The complexes were obtained as mono- and trihydrates with a metal ion to ligand ratio of 1:2. All analysed 4-chloro-2-nitrobenzoates are polycrystalline compounds with colours depending on the central ions: pink for Co(II), green for Ni(II), and blue for Cu(II) complexes. Their thermal decomposition was studied only in the range of 293–523 K, because it was found that on heating in air above 523 K 4-chloro-2-nitrobenzoates decompose explosively. Hydrated complexes lose crystallization water molecules in one step and anhydrous compounds are formed. The final products of their decomposition are the oxides of the respective transition metals. From the results it appears that during dehydration process no transformation of nitro group to nitrite takes place. The solubilities of analysed complexes in water at 293 K are of the order of 10–4–10–2 mol dm–3. The magnetic moment values of Co2+, Ni2+ and Cu2+ ions in 4-chloro-2-nitrobenzoates experimentally determined at 76–303 K change from 3.89 to 4.82 μB for Co(II) complex, from 2.25 to 2.98 μB for Ni(II) 4-chloro-2-nitrobenzoate, and from 0.27 to 1.44 μB for Cu(II) complex. 4-chloro-2-nitrobenzoates of Co(II), and Ni(II) follow the Curie–Weiss law. Complex of Cu(II) forms dimer.

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Abstract  

The new bridged diacetato–diamido–diamine–uranyl complex {2[(UO2)(H2N)(H3N)(OOCCH3)]} was prepared and characterized by elemental analysis, IR measurement as well as TG and DTA analysis. The kinetic parameters; activation energy (E a), pre-exponential factor (A) and the order of decomposition (n) were calculated from TG curves using Coats–Redfern and Flynn–Wall–Ozawa methods. The mechanism of decomposition has been established from TG and DTA data. The data obtained agree quite well with the expected structure and show that the complex finally decomposes to form UO3. A general mechanism describing the formation of bridged complex {2[(UO2)(H2N)(H3N)(OOCCH3)]} is proposed.

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Journal of Thermal Analysis and Calorimetry
Authors: J. Maul, A. S. Brito, A. L. M. de Oliveira, S. J. G. Lima, M. A. M. A. Maurera, D. Keyson, A. G. Souza, and I. M. G. Santos

combustion, while the small mass loss above 600 °C was due to the elimination of hydroxyl groups. Fig. 2 IR spectra of the CuO synthesized at 150 °C/60 min. ( a ) W/A; ( b ) with NH 4 OH; and ( c ) with NaOH

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- b -PHEMA 23 - b -PDMAEMA 156 47,208 1.35 FT-IR spectra of two different triblock copolymers, P t BMA- b -PGMA- b -PSt ( Fig. 2 a

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-IR ( Fig. 3a ). The temperature-dependent FT-IR spectra reveal changes in absorbance in the 1,300–2,000 cm −1 range, and at >3,500 cm −1 , characteristic of H 2 O(g), and at ∼1,000 cm −1 , due to NH 3 (g) ( Fig. 3b ). Release of these gases is maximized

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Journal of Thermal Analysis and Calorimetry
Authors: Corina Duda-Seiman, T. Vlase, Gabriela Vlase, Rodica Cinca, Mariana Anghel, and N. Doca

absent. Also the hypothese of the total thermooxidation as the second process is supported by the EG spectrum at 320 °C, where the major compounds are water vapor and carbon dioxide (see Fig. 4 ). Fig. 3 IR

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Copper(II) acetates with aliphatic/heterocyclic amines

Coupled TG-DTA-EGA study, IR characterization and structure correlation

Journal of Thermal Analysis and Calorimetry
Authors: V. ZeleÔák, Z. Vargová, Katalin Györyová, E. Ve?erníková, and V. Balek

Summary  

Three copper acetate complex compounds, namely Cu(CH3COO)2(en)22H2O (I), Cu(CH3COO)2(tn)2(II) and Cu2(CH3COO)4(pyz) (III) (en=ethylenediamine, tn=1,3-diaminopropane, pyz=pyrazine), were prepared and characterized during heating in argon by thermogravimetry (TG), differential thermal analysis (DTA) and evolved gas analysis (EGA) using mass spectrometry (MS). The results of infrared spectroscopy (IR) were evaluated to be used as a spectroscopic criterion for the determination of the carboxylate binding mode in the compounds.

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