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Effects of O addition on the thermal behaviour of hard W-N sputtered coatings

Louro, C.; Oliveira, J. C.; Cavaleiro, A.
Fonte: Elsevier Ltd. Publicador: Elsevier Ltd.
Tipo: Artigo de Revista Científica
Português
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The structural thermal behaviour of three W-O-N sputtered coatings with similar metalloid to metal ratio (~2.1) was investigated up to 900 °C after annealing in a vacuum tube furnace as well as in-situ HT-XRD under a controlled atmosphere of Ar-5%H2. The as-deposited microstructure of the coatings consisting in a nanocomposite of low-order W-O and W-N phases evaluated differently as a function of the oxygen content. The W-O-N film containing more than 27 at.% O delaminated severely from the steel substrates for temperatures as low as 500 °C. In opposite, for the coatings with less O content, the low range order of the as-deposited structure was maintained up to 800 °C and with further annealing crystallized into a mixture of WO2 and W2N. The thermal behaviour of the oxynitride films overcame that observed for oxygen-free nitride ones. This is due to the greater N content retaining during annealing treatment, in opposite to the W-N films which give rise to the single metallic [alpha]-W phase. The structural and compositional evolution supported the hardness behaviour obtained by the thermal treatment in protective ambiance

Synthesis, characterization and thermal behaviour on solid pyruvates of light trivalent lanthanides

Siqueira, A. B.; Carvalho, C. T. de; Rodrigues, E. C.; Ionashiro, E. Y.; Bannach, Gilbert; Ionashiro, M.
Fonte: Editora Unesp Publicador: Editora Unesp
Tipo: Artigo de Revista Científica Formato: 49-54
Português
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Foram sintetizados compostos Ln-L no estado sólido, onde Ln significa os lantanídeos leves trivalentes e L é o piruvato. Estes compostos foram caracterizados e estudados utilizando-se a Termogravimetria e Termogravimetria derivada (TG/DTG), calorimetria exploratória diferencial (DSC) difratometria de raios X pelo método do pó, espectroscopia na região do infravermelho, análise elementar e complexometria. Os resultados permitiram obter informações com respeito a composição, desidratação, sitio de coordenação, comportamento térmico e a decomposição térmica destes compotos.; Solid State Ln-L compounds, where Ln stands for light trivalent lanthanides (La - Gd) and 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, ligand denticity, thermal behaviour and thermal decomposition of the isolated compounds.

Synthesis, characterization and thermal behaviour of solid-state compounds of benzoates with some bivalent transition metal ions

Siqueira, Adriano B.; Ionashiro, Elias Y.; Carvalho, Cláudio T. de; Bannach, Gilbert; Rodrigues, Emanuel C.; Ionashiro, Massao
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: 318-322
Português
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675.8022%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Solid-state MBz compounds, where M stands for bivalent Mn, Fe, Co, Ni, Cu and Zn and Bz is benzoate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), infrared spectroscopy and complexometry were used to characterize and to study the thermal behaviour of these compounds. The procedure used in the preparation of the compounds via reaction of basic carbonates with benzoic acid is not efficient in eliminating excess acid. However the TG-DTA curves permitted to verify that the binary compounds can be obtained by thermosynthesis, because the benzoic acid can be eliminated before the thermal decomposition of these compounds. The results led to information about the composition, dehydration, thermal stability, thermal decomposition and structure of the isolated compounds. on heating, these compounds decompose in two (Mn, Co, Ni, Zn) or three (Fe, Cu) steps with formation of the respective oxide (Mn3O4, Fe2O3, Co3O4, NiO, CuO and ZnO) as final residue. The theoretical and experimental spectroscopic studies suggest a covalent bidentate bond between ligand and metallic center.

Synthesis, characterization and thermal behaviour on solid tartrates of some bivalent metal ions

Rodrigues, Emanuel C.; Carvalho, Claudio T.; de Siqueira, Adriano B.; Bannach, Gilbert; Ionashiro, Massao
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 156-160
Português
Relevância na Pesquisa
675.8022%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Solid-state M-L compounds, where M stands for bivalent Mn, Fe, Co, Ni, Cu, Zn and L is tartrate, have been synthesized. 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 TG-DTA and DSC curves show that the manganese, cobalt and nickel compounds are hydrated while iron, copper and zinc ones are anhydrous. The thermal stability of the anhydrous compounds depends on the nature of the metal ion, and it follows the order: Zn > Cu > Mn = Co > Ni > Fe. These Curves also show that the thermal decomposition Occurs in a single step to the respective metal oxides. The results led to information about the composition, dehydration, ligand denticity and thermal decomposition of the isolated compounds. (C) 2009 Elsevier B.V. All rights reserved.

Synthesis, characterization and thermal behaviour of solid state compounds of 4-methoxybenzoate with Manganese, Nickel and Copper

Rodrigues, E. C.; Vallejo, A. C.; Ionashiro, E.Y.; Bannach, Gilbert; Ionashiro, M.
Fonte: Editora Unesp Publicador: Editora Unesp
Tipo: Artigo de Revista Científica Formato: 15-20
Português
Relevância na Pesquisa
674.838%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Compostos M - L foram sintetizados no estado sólido, onde M representa os íons bivalentes Mn, Ni, Cu e L é o ânion 4 - metoxibenzoato. Esses compostos foram caracterizados e estudados, utilizando-se as técnicas de difração de raios x pelo método do pó, espectroscopia na região do infravermelho, análise elementar, complexometria e termogravimetria - análise térmica diferencial simultânea (TG - DTA). Os resultados permitiram obter informações com respeito à estequiometria, desidratação, estabilidade térmica e decomposição térmica.; Solid state M-L compounds, where M stands for bivalent Mn, Ni, Cu and L is 4-methoxybenzoate, have been synthesized. Simultaneous thermogravimetry - differential thermal analysis (TG-DTA), 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 thermal decomposition of the isolated compounds.

Synthesis, characterization and thermal behaviour of solid-state compounds of 2-methoxybenzoate with some bivalent transition metal ions

Carvalho, C.T; Siqueira, A. B; Rodrigues, E. C; Ionashiro, M
Fonte: Editora Unesp Publicador: Editora Unesp
Tipo: Artigo de Revista Científica Formato: 19-26
Português
Relevância na Pesquisa
674.838%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); compostos M-2-MeO-Bz foram sintetizados no estado sólido, onde M representa os íons bivalentes Mn, Co, Ni, Cu e Zn e 2-MeO-Bz é o anion 2-metoxibenzoato. Esses compostos foram caracterizados e estudados, utilizando-se técnicas de difração de raios X pelo método do pó, espectroscopia na região do infravermelho, complexometria e analise térmica diferencial simultânea (TG-DTA), thermogravimetry, derivative thermogravimetry (TG/DTG) e calorimetria exploratória diferencial (DSC). Os resultados permitiram obter informações com respeito a estequiometria, desidratação, estabilidade térmica e decomposição térmica.; Solid-state M-2-MeO-Bz compounds, where M stands for bivalent Mn, Co, Ni, Cu and Zn and 2-MeO-Bz is 2-methoxybenzoate, have been synthesized. Simultaneous thermogravimetry-differential thermal analysis (TG-DTA), thermogravimetry, derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to have information about the composition...

Synthesis, characterization and thermal behaviour of solid 2-methoxycinnamylidenepyruvate of some bivalent metal ions in CO2 and N2 atmospheres

Carvalho, C. T. de; Siqueira, A. B.; Ionashiro, E. Y.; Ionashiro, M.
Fonte: Editora Unesp Publicador: Editora Unesp
Tipo: Artigo de Revista Científica Formato: 55-62
Português
Relevância na Pesquisa
674.838%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Compostos M-2-MeO-CP foram sintetizados no estado sólido, onde M representa os metais bivalentes (Mn(II), Fe(II), Co(II), Ni(II), Cu(II) e Zn(II)) e 2-MeO-CP é o 2-metoxicinamalpiruvato. Para estabelecer a estequiometria e estudar o comportamento térmico desses compostos foram utilizadas termogravimetria, análise térmica diferencial simultânea (TG-DTA), calorimetria exploratória diferencial (DSC), análise elementar e complexometria com EDTA. Os resultados foram concordantes com a fórmula geral: M(L)2∙H2O. em ambas as atmosferas a decomposição térmica ocorre em etapas consecutivas e é característica de cada composto. em atmosfera de CO2 os resíduos finais foram: Mn3O4, Fe3O4, Co3O4, NiO, Cu2O e ZnO, enquanto que em atmosfera de N2 a decomposição térmica ainda é observada até 1000 ºC.; Solid State M-2-MeO-CP compounds, where M stands for bivalent metals (Mn, Fe, Co, Ni, Cu and Zn) and 2-MeO-CP is 2-methoxycinnamylidenepyruvate, were synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA)...

Synthesis, characterization and thermal behaviour of solid 4-methoxybenzoates of heavier trivalent lanthanides

Rodrigues, Emanuel C.; Siqueira, Adriano B.; Ionashiro, Elias Y.; Bannach, Gilbert; Ionashiro, Massao
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 149-155
Português
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677.5538%
Solid-state Ln-4-MeO-Bz compounds, where Ln stands for trivalent Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y and 4-MeO-Bz is 4-methoxybenzoate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, phase transition, coordination mode, structure, thermal behaviour and thermal decomposition of the isolated compounds. The phase transition observed in the some compounds has been reported for the first time. (C) 2006 Elsevier B.V. All rights reserved.

Thermal behaviour of fumaric acid, sodium fumarate and its compounds with light trivalent lanthanides in air atmosphere

Ionashiro, E. Y.; Caires, Flavio J.; Siqueira, A. B.; Lima, L. S.; Carvalho, C. T.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 1183-1188
Português
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676.5567%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Characterization, thermal stability and thermal decomposition of light trivalent lanthanide fumarates, as well as, the thermal behaviour of fumaric acid and its sodium salt were investigated employing simultaneous thermogravimetry and differential thermal analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy (FTIR), TG-FTIR techniques, elemental analysis and complexometry. on heating, sublimation of fumaric acid is observed, while the thermal decomposition of the sodium fumarate occurs with the formation of a mixture of sodium carbonate and carbonaceous residue. The thermal decomposition of light trivalent lanthanide fumarates occurs in consecutive and/or overlapping steps with the formation of the respective oxides: CeO2, Pr6O11, and Ln(2)O(3) (Ln = La, Nd, Sm, Eu, Gd).

Synthesis, characterization and thermal behaviour of solid 2-methoxybenzoates of trivalent metals

Siqueira, A. B.; Carvalho, C. T.; Ionashiro, E. Y.; Bannach, Gilbert; Rodrigues, E. C.; Ionashiro, M.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 945-951
Português
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677.5538%
Solid-state Ln(L)(3) compounds, where Ln stands for trivalent Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y and L is 2-methoxybenzoate have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results provided information on the composition, dehydration, coordination mode, structure, thermal behaviour and thermal decomposition.

Synthesis, characterization and thermal behaviour of solid-state compounds of light trivalent lanthanide succinates

Lima, L. S.; Caires, Flavio J.; Carvalho, C. T.; Siqueira, A. B.; Ionashiro, M.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 50-54
Português
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675.8022%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Characterization, thermal stability and thermal decomposition of light trivalent lanthanide succinates, Ln(2)(C(4)H(4)O(4))(3)center dot nH(2)O (Ln = La to Gd, except Pm) were investigated employing simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), infrared spectroscopy, TG-FTIR system, elemental analysis and complexometry. The dehydration of the lanthanum and cerium compounds occurs in a single step, while for the praseodymium to gadolinium compounds the dehydration occurs in two consecutive steps. The thermal decomposition of the anhydrous compounds occurs in consecutive and/or overlapping steps, except for the cerium compound, with formation of the respective oxides, CeO(2), Pr(6)O(11) and Ln(2)O(3) (Ln = La, Nd to Gd), as final residue. The results also provided information concerning the denticity of the ligand and thermal behaviour of these compounds. (C) 2010 Elsevier BM. All rights reserved.

Thermal behaviour of succinic acid, sodium succinate and its compounds with some bivalent transition metal ions

Caires, Flavio J.; Lima, L. S.; Carvalho, C. T.; Ionashiro, M.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 6-12
Português
Relevância na Pesquisa
679.2726%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Characterization, thermal stability and thermal decomposition of transition metal succinates, MC(2)H(4)C(2)O(4)center dot nH(2)O (M = Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II)), the thermal behaviour of succinic acid (C(4)H(6)O(4)) and its sodium salt (Na(2)C(2)H(4)C(2)O(4)center dot 6H(2)O) were investigated employing simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), infrared spectroscopy, TG-FTIR system, elemental analysis and complexometry. For the hydrated compounds the dehydration and the thermal decomposition of the anhydrous compounds occur in a single step. For the sodium succinate the final residue up to 545 degrees C is sodium carbonate, while the transition metal succinates the final residues are Mn(3)O(4), Fe(2)O(3), Co(3)O(4), NiO, CuO and ZnO, respectively. The results also provided information concerning the thermal behaviour and identification of gaseous products evolved during the heating of these compounds. (C) 2009 Elsevier B.V. All rights reserved.

Synthesis, characterization and thermal behaviour of solid-state compounds of 4-methoxybenzoate with some bivalent transition metal ions

Rodrigues, E. C.; Siqueira, A. B.; Ionashiro, E. Y.; Bannach, G.; Ionashiro, M.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 323-328
Português
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675.8022%
Solid-state M-4-MeO-Bz compounds, where M stands for bivalent Mn, Co, Ni, Cu and Zn and 4-MeO-Bz is 4-methoxybenzoate, have been synthesized. Simultaneous thermogravimetry-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 have information about the composition, dehydration, thermal stability and thermal decomposition of the isolated compounds. © 2005 Akadémiai Kiadó, Budapest.

Thermal behaviour of nicotinic acid, sodium nicotinate and its compounds with some bivalent transition metal ions

Nascimento, A. L. C. S. do; Caires, F. J.; Gomes, D. J. C.; Gigante, A. C.; Ionashiro, M.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 212-218
Português
Relevância na Pesquisa
679.8792%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Solid-state M(L)(2)center dot nH(2)O compounds, where M stands for bivalent transition metals (Mn, Fe, Co, Ni, Cu and Zn), L is nicotinate and n = 0-4.5, have been synthesized. Characterization and thermal behaviour of these compounds were investigated employing elemental analysis based on the mass losses observed in the TG-DTA curves, complexometry, X-ray diffractometry, infrared spectroscopy (FTIR), simultaneous thermogravimetric and differential thermal analysis (TG-DTA) and TG-DSC coupled to FTIR. The thermal behaviour of nicotinic acid and its sodium salt was also investigated. For the hydrated transition metal compounds, the dehydration and thermal decomposition of the anhydrous compounds occur in a single step. For the sodium nicotinate, the final residue up to 765 degrees C is sodium carbonate and for the transition metal nicotinates, the final residues are Mn3O4, Fe2O3, Co3O4, NiO, CuO and ZnO. The results also provided information concerning the thermal stability, thermal decomposition and identification of the gaseous products evolved during the thermal decomposition of the compounds. (C) 2013 Published by Elsevier B.V.

The evaluation of the thermal behaviour of a mortar based brick masonry wall coated with TiO2 nanoparticles : an experimental assessment towards energy efficient buildings

Carneiro, Joaquim A. O.; Vasconcelos, Graça; Azevedo, Sofia; Jesus, Carlos; Palha, Carlos; Gomes, Nuno; Teixeira, Vasco
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2014 Português
Relevância na Pesquisa
675.8022%
The transfer of energy (in the form of heat) between the building and its surroundings affects its thermal performance. When a given building system is thermally inefficient it will require that the HVAC equipment will be in permanent activity, increasing the underlying energy costs. This work evaluates the influence of using a TiO2-coated plastering mortar in the thermal performance of a building wall model. The TiO2 aqueous solution was sprayed onto the mortar surface, in its fresh state, by using an atmospheric air compressor at a distance of about 20 cm, during 30 s and the speed of the aqueous solution jet set at 100 mL/min, thus leading to a coverage rate of about 12 mg/cm2.For the first time, as far as the authors’ knowledge, this research work allowed to test the previously speculated hypothesis and verify its feasibility in the building industry context. It has been observed that the application of a TiO2-coated mortar worsens the thermal behaviour of the wall model, in 10% and 13% for the conduction thermal resistance and for thermal transmission coefficient, respectively. Furthermore, the deposition of TiO2 nanoparticles on the exterior wall surface enhances the water evaporation rate in 136%.

Synthesis, characterization and thermal behaviour of solid-state compounds of benzoates with some bivalent transition metal ions

Siqueira,Adriano B.; Ionashiro,Elias Y.; Carvalho,Cláudio T. de; Bannach,Gilbert; Rodrigues,Emanuel C.; Ionashiro,Massao
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2007 Português
Relevância na Pesquisa
675.8022%
Solid-state MBz compounds, where M stands for bivalent Mn, Fe, Co, Ni, Cu and Zn and Bz is benzoate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), infrared spectroscopy and complexometry were used to characterize and to study the thermal behaviour of these compounds. The procedure used in the preparation of the compounds via reaction of basic carbonates with benzoic acid is not efficient in eliminating excess acid. However the TG-DTA curves permitted to verify that the binary compounds can be obtained by thermosynthesis, because the benzoic acid can be eliminated before the thermal decomposition of these compounds. The results led to information about the composition, dehydration, thermal stability, thermal decomposition and structure of the isolated compounds. On heating, these compounds decompose in two (Mn, Co, Ni, Zn) or three (Fe, Cu) steps with formation of the respective oxide (Mn3O4, Fe2O3, Co3O4, NiO, CuO and ZnO) as final residue. The theoretical and experimental spectroscopic studies suggest a covalent bidentate bond between ligand and metallic center.

Synthesis, characterization and thermal behaviour on solid pyruvates of light trivalent lanthanides

Siqueira,A. B.; Carvalho,C. T. de; Rodrigues,E. C.; Ionashiro,E. Y.; Bannach,G.; Ionashiro,M.
Fonte: Fundação Editora da Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP Publicador: Fundação Editora da Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2007 Português
Relevância na Pesquisa
676.2787%
Solid State Ln-L compounds, where Ln stands for light trivalent lanthanides (La - Gd) and 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, ligand denticity, thermal behaviour and thermal decomposition of the isolated compounds.

Synthesis, characterization and thermal behaviour of heavy trivalent lanthanide malonates

Locatelli,J. R.; Carvalho,C. T.; Caires,F. J.; Ionashiro,M.
Fonte: Fundação Editora da Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP Publicador: Fundação Editora da Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2010 Português
Relevância na Pesquisa
677.5538%
Solid-state Ln-L compounds, where Ln stands for heavy trivalent lanthanides (Tb-Lu) and L is malonate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy, TG-FTIR system, elemental analysis and complexometry were used to characterize and to study the thermal behaviour of these compounds. The dehydration of the compounds begins at 303 K and the anhydrous compounds are stable up to 548 K. The results also provided information concerning the ligand's denticity, thermal behaviour and identification of some gaseous products evolved during the thermal decomposition of these compounds.

Synthesis, characterization and thermal behaviour of solid-state compounds of 4-methoxybenzoate with lanthanum (III) and trivalent lighter lanthanides

Rodrigues,E. C.; Siqueira,A. B.; Ionashiro,E. Y.; Bannach,G.; Ionashiro,M.
Fonte: Fundação Editora da Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP Publicador: Fundação Editora da Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2006 Português
Relevância na Pesquisa
677.5538%
Solid-state M-4-MeO-Bz compounds, where M stands for trivalent La, Ce, Pr, Nd and Sm and 4-MeO-Bz is 4-methoxybenzoate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, polymorphic transformation, ligand's denticity, thermal behaviour and thermal decomposition of the isolated compounds.

Thermal behaviour and detonation characterization of N-benzoyl-3, 3-dinitroazetidine

Yan,Biao; Zhao,Ning Ning; Ma,Hai Xia; Song,Ji Rong; Zhao,Feng Qi; Hu,Rong Zhu
Fonte: South African Journal of Chemistry Publicador: South African Journal of Chemistry
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2013 Português
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677.66164%
N-benzoyl-3,3-dinitroazetidine(BDNAZ) is a derivative of 3,3-dinitroazetidine (DNAZ). Its thermal behaviour was studied by DSC methods. The results show that there are one melting process and two exothermic decomposition processes. The kinetic parameters of the intense exothermic decomposition process were obtained from the analysis of the DSC curves. The apparent activation energy, pre-exponential factor and the mechanism function are 170.77 kJ mol-1,10(14.12) s-1 and f(α) = (1-a)-1/2, respectively. The specific heat capacity of BDNAZ was determined with a continuous Cp mode of a micro-calorimeter. The standard mole specific heat capacity of BDNAZ was 286.31 J mol¹ K-1 at 298.15 K. Using the relationship between Cp and T with the thermal decomposition parameters, the time of the thermal decomposition from initialization to thermal explosion (adiabatic time-to-explosion, tTIAD), the self-accelerating decomposition temperature (TSADT), thermal ignition temperature (T TIT), critical temperatures of thermal explosion (Tb) and period of validity (t0.9) were obtained to evaluate its thermal safety. The detonation velocity (D) and pressure (P) of BDNAZ were estimated by using the nitrogen equivalent equation according to the experimental density.