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Abstract  

Solid-state Ln–C8H7O3 compounds, where Ln stands for Eu(III) and Gd(III) and C8H7O3 is 3-methoxybenzoate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy, elemental analysis and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, thermal stability and decomposition of the isolated compounds.

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Abstract  

The thermal behavior of the Cu-10 mass%Al and Cu-10 mass%Al-4 mass%Ag alloys was studied using classical differential thermal analysis (DTA), optical microscopy (OM) and X-ray diffractometry (XRD). The DTA curves were obtained for annealed and quenched samples. The results indicated that the presence of silver introduces new thermal events, associated to the formation of a silver-rich phase, to the shift of the equilibrium concentration to higher Al contents and to the decomposition of the silver-rich phase in the same temperature range of the b1 phase decomposition.

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Abstract  

Solid-state Ln(L)3 compounds, where Ln stands for trivalent Tb, Dy, Ho, Er, Tm, Yb, Lu and Y, and L is 3-methoxybenzoate, have been synthesized. X-ray powder diffractometry, infrared spectroscopy, complexometry and elemental analysis were used to characterize the compounds. In order to study the thermal behaviour of these compounds simultaneous thermogravimetry and differential thermal analysis (TG-DTA) and differential scanning calorimetry (DSC) were used. The results provided information on the composition, dehydration, polymorphic transformation, thermal stability and thermal decomposition of the synthesized compounds.

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Journal of Thermal Analysis and Calorimetry
Authors: Elena Mosoarca, Sasca Viorel, Livia Avram, Ramona Tudose, and Otilia Costisor

Abstract  

The thermal decomposition in air and in nitrogen atmosphere of binuclear complex compounds of Cu(II) and Co(II) containing the Mannich base N,N′-tetra(4-antipyrylmethyl)-1,2 diaminoethane (TAMEN) as a ligand, Cu2(TAMEN)Cl4 and Co2(TAMEN)Cl4, were investigated. X-ray powder diffractometry, infrared spectroscopy and simultaneous thermogravimetry-differential thermal analysis (TG-DTA), have been used to characterize and to study the thermal behavior of these compounds. The results provided information concerning the stoichiometry, crystallinity, thermal stability and decomposition mechanism of the compounds.

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Summary The thermal behavior of poly(L-lactic acid) (PLLA) was studied with differential scanning calorimetry (DSC) and polarized optical microscopy. For amorphous PLLA samples, double cold crystallisation peaks were observed in the DSC traces during heating process, being strongly dependent on heating rates. The observation was discussed based on the assumption that the quenched PLLA sample presented some remaining metastable or a precrystalline phase. A small exothermal peak was observed before the main melting peak at low heating rates. The probable reason was discussed through melt-recrystallisation mechanism. Influence of thermal history on the cold crystallisation and melting behavior was also performed on heating process for PLLA samples.

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these phenomena [ 20 – 32 ]. This study is an effort to investigate the thermal behaviour of tin(II/IV) phosphates prepared in different ways. Experimental Synthesis The typical methods of synthesis

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and cadmium sulfide particles into sol-gel zirconium phosphate. Synthesis, thermal behavior and X-ray characterization . J Therm Anal Calorim 63 : 709 – 721 10.1023/A:1010183819410 . 15

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Abstract  

The investigations concerning the thermal behaviour of a series of Ni(II) and Cu(II) complexes of type [NiLCl2mH2O ((1) L:L1, m=6; (3) L:L2, m=4) or [CuLCl]nCln·mnH2O ((2) L:L1, m=6; (4) L:L2, m=4) are presented. The ligands L(1) and L(2) have been synthesised by template condensation of 3,6-diazaoctane-1,8-diamine or 1,2-diaminoethane with formaldehyde and 2-amino-4H-1,2,4-triazole. The bonding and stereochemistry of the complexes have been characterised by IR, electronic and magnetic studies at room temperature. The in vitro qualitative and quantitative antimicrobial activity assays showed that the complexes exhibited variable antimicrobial activity against planktonic as well as biofilm embedded Gram-negative, Gram-positive and fungal strains. The thermal behaviour provided confirmation of the complexes composition as well as the number and nature of water molecules and the intervals of thermal stability.

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thermal properties of yttria fully-stabilized zirconia . J Therm Anal Calorim . 2009 ; 98 2 343 – 346 10.1007/s10973-009-0297-8 . 40. Szirtes , L , Megyeri , J , Kuzmann , E . Thermal

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, Chrissafis K , Lalia-Kantouri M . Luminescence and thermal behavior by simultaneous TG/DTG-DTA coupled with MS of neutral copper(I) complexes with heterocyclic thiones . J Therm Anal Calorim. 2010 . doi: 10.1007/s10973

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