11 research outputs found

    Lornoxicam drug—A new study of thermal degradation under oxidative and pyrolysis conditions using the thermoanalytical techniques, DRX and LC-MS/MS

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    In the present work, the thermal behavior of Lornoxicam drug was studied under oxidizing (air) and pyrolysis (N2) atmospheres using simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC), differential scanning calorimetry (DSC), Hot Stage Microscopy (HSM) and Evolved Gas Analysis (EGA) in the form of thermogravimetry coupled to infrared spectroscopy (TG-FTIR) and mass spectrometry (TG-MS). The thermal degradation product formed at different temperatures were examined using liquid chromatography coupled to mass spectrometry (LC–MS) and Powder X-Ray Diffraction (PXRD). The thermal study showed that the drug does not melt, partially amorphized on heating, it is thermally stable to 205 °C and undergoes thermal decomposition in two overlapping mass loss steps. Furthermore, the DSC and MS techniques suggest that thermal degradation processes are very complex, which occur with the release of gaseous products HCN, SO2, COS, CO2, N2O and CO and formation of three intermediate in the thermal residue

    Thermal Behavior, Spectroscopic Studies And Free Radical Scavenging Potential Of Some Mefenamate Trivalent Lanthanides (sm, Eu, Gd, Tb And Dy)

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    Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Lanthanide Mefenamate compounds were prepared in solid state. TG-DSC coupled to FTIR, elemental analysis, complexometry with EDTA, X-ray powder diffractometry, evaluation of scavenging free radical activity with DPPH (2,2-diphenyl-1-picryl-hydrazine), and a complete spectroscopic study in the ultraviolet, visible, near-, and middle-infrared regions were realized to obtain some physicochemical properties of the synthesized compounds. The thermal stability, minimum formula, thermal behavior and intermediate compounds were indicated by thermoanalytical results. Furthermore, vibrational spectroscopy data suggests that the complexes are binuclear and two modes of coordination are presented. The DR spectra could be reveal the presence of a large ligand-to-metal charge transfer band in the europium mefenamate. This compound also indicated the higher antioxidant activity with DPPH (77.03% at 200 μg L−1). © 2017 Elsevier B.V.6517382CAPES, Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorCNPq, Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPESP, Fundação de Amparo à Pesquisa do Estado de São PauloCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Thermal behavior, spectroscopic studies and free radical scavenging potential of some mefenamate trivalent lanthanides (Sm, Eu, Gd, Tb and Dy)

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    Lanthanide Mefenamate compounds were prepared in solid state. TG-DSC coupled to FTIR, elemental analysis, complexometry with EDTA, X-ray powder diffractometry, evaluation of scavenging free radical activity with DPPH (2,2-diphenyl-1-picryl-hydrazine), and a complete spectroscopic study in the ultraviolet, visible, near-, and middle-infrared regions were realized to obtain some physicochemical properties of the synthesized compounds. The thermal stability, minimum formula, thermal behavior and intermediate compounds were indicated by thermoanalytical results. Furthermore, vibrational spectroscopy data suggests that the complexes are binuclear and two modes of coordination are presented. The DR spectra could be reveal the presence of a large ligand-to-metal charge transfer band in the europium mefenamate. This compound also indicated the higher antioxidant activity with DPPH (77.03% at 200 μg L−1).6517382CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informaçãoSem informaçãoSem informaçã

    Deposição do enxofre atmosférico no solo pelas precipitações pluviais e respostas de culturas à adubação sulfatada em sistema plantio direto Soil sulphur atmospheric depositions by pluvial precipitations and crops responses to sulfated fertilization in no-tillage system

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    Entre vários fatores que podem mascarar a ocorrência de respostas das plantas ao enxofre, destaca-se a deposição atmosférica via água da chuva. O objetivo deste trabalho foi avaliar a quantidade de sulfato presente na água das chuvas e as respostas de diferentes culturas à adubação sulfatada. Foi utilizado um experimento instalado a campo, em 2002, sobre um Argissolo Vermelho distrófico arênico, em sistema plantio direto, num esquema bifatorial com quatro doses de sulfato e duas sucessões de culturas. No período de julho de 2002 a dezembro de 2003, foram realizados três cultivos, aplicando-se as doses de 0, 15, 30 e 60kg de S-SO4-2 ha-1 no primeiro cultivo, 1/3 dessas doses no segundo cultivo e no terceiro não foi aplicado S-SO4-2. A partir de maio de 2004, foi avaliado mais um ciclo de três cultivos (aveia preta/feijoeiro/trigo e aveia preta/soja/canola), para os quais as doses de S-SO4-2 foram reaplicadas antes da implantação das culturas, exceto a da aveia preta. Durante o período de setembro de 2004 a novembro de 2005, quantificou-se o aporte de enxofre via água das chuvas. Somente o feijoeiro respondeu à aplicação de sulfato. A ausência de resposta das demais culturas pode estar relacionada com a deposição atmosférica pela água da chuva, cujo valor determinado foi de 3,2kg de enxofre ha-1 ano-1, e com a mineralização dos resíduos culturais, que devem ter sido suficientes para atender a demanda das plantas.<br>Some factors, such as atmospheric sulphur deposition by rain, may mask the crops response to fertilizers containing sulphur. This experiment was carried out to study (a) crop yields response to sulphur, and (b) sulphur deposition by rain. An experiment was installed in 2002 Winter, and cultivated to three crops sequences until December 2003, with sulfate rate of 0, 15, 30, and 60kg ha-1 for the first crop, 1/3 rates for the second crop and nil on the third. From May 2004 to October 2005, it was cultivated two new cultures in each crops system (black oat / bean / wheat and black oat / soybean / colza). The same sulfate rates applied in 2002 were again applied to second and third crops. The atmospheric sulphur deposition was evaluated by sampling all rain events from September 2004 to November 2005. Only bean responded to sulfate application. No response observed to other crop yields may be attributed to the sulphur atmospheric deposition and organic matter mineralization. The sulphur atmospheric deposition was 3.2kg ha-1 year-1 which is equivalent to almost 10kg ha-1 year-1 of sulfate
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