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Journal of Thermal Analysis and Calorimetry
Authors: Liang Xue, Feng-Qi Zhao, Xiao-Ling Xing, Zhi-Ming Zhou, Kai Wang, Hong-Xu Gao, Jian-Hua Yi, Si-Yu Xu, and Rong-Zu Hu

, which shows that the thermal behavior of 1,2,3-triazole nitrate can be divided into two stages. The first stage is a melting process. The second stage is an intense exothermic decomposition process. The characteristic temperatures of exothermic

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Journal of Thermal Analysis and Calorimetry
Authors: Eveline De Robertis, Gabriela F. Moreira, Raigna A. Silva, and Carlos A. Achete

for thermal behavior studies, since by the standard method for such determinations the major drawback is the time of analysis. In this work, our intention is verify the thermal behavior of two standard reference materials (SRM) using DSC, such

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Journal of Thermal Analysis and Calorimetry
Authors: Eudes Lorençon, Rodrigo G. Lacerda, Luiz O. Ladeira, Rodrigo R. Resende, André S. Ferlauto, Ulf Schuchardt, and Rochel M. Lago

.e., 10 6 –10 8 . This result again suggests that Au does not have any catalytic effect on the carbon oxidation of SWNT. Conclusions This study presents the thermal behavior of MWNT, SWNT, and CNP samples decorated with Au

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Journal of Thermal Analysis and Calorimetry
Authors: D. Wyrzykowski, E. Hebanowska, G. Nowak-Wiczk, M. Makowski, and L. Chmurzyński

broader characteristics of its thermal behaviour. To be able to do this, we have examined the intermediate dehydration products of the acid, trans -aconitic acid ( trans -propene-1,2,3-tricarboxylic acid) and its cis -isomer, cis -propene-1

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The thermal behaviours of magnesium sulfite, strontium sulfite and barium sulfite were investigated in the atmospheres of argon and air. the thermal behaviours of magnesium sulfite were different from those of the other two sulfites. The oxidation of magnesium sulfite in air does not occur.

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Abstract  

Solid-state Ln–L compounds, where Ln stands for heavy trivalent lanthanides or yttrium (III) (Tb–Lu, Y) and where L is pyruvate, have been synthesized. Thermogravimetry and derivative thermogravimetry (TG/DTG), 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 behaviour, ligand denticity of the isolated complexes.

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Journal of Thermal Analysis and Calorimetry
Authors: Rodica Olar, Mihaela Badea, Veronica Lazar, Carmen Balotescu, Elena Cristurean, and Dana Marinescu

Abstract  

N,N-Dimethylbiguanide derivatives (HDMBG)X, where X=CH3COO (1), Cl (2) and NO3 (3) respectively, exhibit in vitro antimicrobial activity on representative bacterial and fungal strains. The presence of N,N-dimethylbiguanidium ion for all derivatives was evidenced by IR and 1H NMR spectra. Thermal analysis gave information on their decomposition steps and also on the accompanying thermodynamic effects. According to TG and DTG curves processes as melting, oxidative degradation as well as oxidative condensation of –C=N– units occur. The different nature of the anions results different melting points. Paracyanide formation at various condensation degrees was observed.

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Abstract  

Curing of diglycidyl ether of bisphenol-A (DGEBA) with phosphorus containing amide amines i.e. bis[3(3’-aminobenzamido phenyl)]methyl phosphine oxide (MB),bis[3(4’-aminobenzamido phenyl)]methyl phosphine oxide (PB), tris[3(3’-aminobenzamidophenyl)] phosphine oxide (MT) and tris[3(4’-aminobenzamido phenyl)] phosphine oxide (PT)and conventionally used curing agent 4,4’-diaminodiphenyl sulfone (D) was studied by DSC. The amines MB, PB, MT and PT were synthesised in the laboratory and were characterized by determining elemental composition, melting point, and amine equivalent. Structural characterization was done by 1H-NMR and FTIR. The onset temperature of curing depended on the nucleophilicity of the amines and was in the orderMT≈MB<PT<PB<D. The exothermic peak temperatures were in the orderD>PB>PT>MT≈MB. The char residue of cured epoxy resin was significantly higher when phosphorus was incorporated in the cured network. Using mixed amine formulations based on amine D and P-containing amines and the molar ratio of these amines could easily control the curing characteristics. A linear relationship between char yield and P-content was observed in such formulations.

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Abstract  

The basic salt cobalt(II) hydroxide fluoride was obtained by partial hydrolysis of a 0.2M solution CoF2. Mixed Co(II)Cu(II) hydroxide fluorides with an isomorphic substitution of Co(II) by Cu(II) ions up to 20% were also prepared. XRD data obtained on these compounds indicate that they are single-phase compounds, their X-ray powder patterns being almost identical to the Co(OH)0.7F1.3 diagram, with Zn(OH)F-type structure. However, their stoichiometries are very close to Co1−xCux(OH)F (0≤x≤0.2). Thermal analysis studies carried out up to 1273 K in still air or under dynamic vacuum conditions show that in air CoO or a mixture of CoO and CuO is formed as final product. In vacuum, at high temperature, with a Ta heating surface, pure α-Co or a mixture of α-Co and Cu is formed at about 973 K.

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