Thermal stability and thermal decomposition of sucralose

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Preparation and thermal decomposition of copper(II), zinc(II) and cadmium(II) chelates with 8-hydroxyquinoline

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Thermal Behavior of Sr(II) and Ba(II)-Diclofenac Complexes in Solid State: Study of the Dehydration and Thermal Decomposition

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Thermal Study in Solid State of Zn(II)-Diclofenac Complex: Behavior Kinetic of the Dehydration, Transition Phase and Thermal Decomposition

The dehydration, thermal decomposition and transition phase stage of Zn(II)-diclofenac compound were studied by simultaneous TG-DTA and DSC techniques. The TG and DSC curves of this compound were obtained with the mass of sample of 2 and 5 mg. Additionally, DSC curves were carried out in opened and closed alpha-alumina pans under static and nitrogen atmosphere. The DTA and DSC curves show that this compound possesses exothermic transition phase between 170-180 degrees C, which it is irreversible (monotropic reaction) The kinetics study of this transition phase stage was evaluated by DSC under non-isothermal conditions. The obtained data were evaluated with the isoconversional method, where the values of activation energy (E(a) / kJ mol(-1)) was plotted in function of the conversion degree (alpha). The results show that due to mass sample, different activation energies were obtained From these curves a tendency can be seen where the plots maintain the same profile for closed lids and almost run parallel to each other.

Preparation and thermal decomposition of solid state cinnamates of alkali earth metals, except beryllium and radium

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Preparation and thermal decomposition of solid state compounds of 4-methoxybenzylidenepyruvate with alkali earth metals, except beryllium and radium

Solid compounds of general formula ML(2) . nH(2)O [where M is Mg, Ca, Sr or Ba; L=4 methoxybenzylidenepyruvate (4-MeO-BP); n = 4, 1 or 0] have been synthetized. Thermogravimetry (TG), derivative thermogravimetry (DTG), differential scanning calorimetry (DSC), x-ray diffraction powder patterns and elemental analysis have been used to characterize the compounds. The thermal stability of these compounds as well as that of the decomposition products were studied using Pt or Al2O3 crucibles in an air or a CO2 atmosphere.

Preparation and thermal decomposition of solid state compounds of 4-methoxybenzylidenepyruvate and trivalent lanthanides and yttrium

Solid state compounds were prepared of Ln-4-MeO-BP, where Ln is a trivalent lanthanide (except promethium) or yttrium, and 4-MeO-BP is 4-methoxybenzylidenepyruvate. Thermogravimetry-derivative thermogravimetry (TG-DTG), differential scanning calorimetry (DSC) and other methods of analysis have been used to characterize and to study the thermal stability and thermal decomposition of these compounds. © 1993.

Synthesis, characterization and thermal decomposition of [Pd2 (C2-dmba) (μ-SO4) (μ-SO4) SO22]

The bridged sulphate complex [Pd2 (C2,dmba) (μ-SO4) (SO2)2] has been obtained by reacting a saturated solution of SO2 in methanol and the cyclometallated compound [Pd(C2,N-dmba)(μ-N3)]2; (dmba = N,N-dimethylbenzylamine), at room temperature for 24 h. Reaction product was characterized by elemental analysis, NMR comprising 13C{1H} and 1H nuclei and I.R. spectrum's measurements. Thermal behavior has been investigated and residual products identified by X-ray powder diffraction.

Preparation and thermal decomposition of solid-state cinnamates of lighter trivalent lanthanides

Some new compounds of cinnamic acid with lighter trivalent lanthanides were prepared in the solid state. The compounds have general formula ML3·H2O, where L is cinnamate (C6H5-CH=CH-COO-) and M is La, Ce, Pr, Nd or Sm. Thermogravimetry, derivative thermogravimetry, differential scanning calorimetry, infrared absorption spectra and X-ray diffraction powder patterns were used to characterize and to study the thermal stability and thermal decomposition of these compounds.

Thermal study in solid state of Zn(II)-diclofenac complex: Behavior kinetic of dehydration, transition phase and thermal decomposition

The dehydration, thermal decomposition and transition phase stage of Zn(II)-diclofenac compoundwere studied by simultaneous TG-DTA and DSC techniques. The TG and DSC curves of this compoundwere obtained with the mass of sample of 2 and 5 mg. Additionally, DSC curves were carried out inopened and closed a-alumina pans under static and nitrogen atmosphere. The DTA and DSC curves showthat this compound possesses exothermic transition phase between 170-180 ºC, which it is irreversible(monotropic reaction). The kinetics study of this transition phase stage was evaluated by DSC undernon-isothermal conditions. The obtained data were evaluated with the isoconversional method, where thevalues of activation energy (Ea/kJmol-1) was plotted in function of the conversion degree (a). The resultsshow that due to mass sample, different activation energies were obtained. From these curves a tendencycan be seen where the plots maintain the same profile for closed lids and almost run parallel to each other.

Thermal stability and thermal decomposition of the antihypertensive drug amlodipine besylate

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Preparation and thermal decomposition of solid state cobalt, nickel, copper and zinc chelates of ethylenediaminetetraacetic acid

Solid state chelates of general formula H-2[M(EDTA)] . nH2O, where M is Co, Ni, Cu or Zn, and EDTA is ethylenediaminetetraacetate, were prepared. Thermogravimetry-derivative thermogravimetry (TG-DTG), differential thermal analysis (DTA) and complexometry were used to characterize and to study the thermal stability and thermal decomposition of these compounds.

Correlation between i.r. spectra and thermal decomposition of cobalt(II), nickel(II), copper(II) and mercury(II) complexes with piperidinedithiocarbamate and pyrrolidinedithiocarbamate

The thermal decomposition of pyrrolidinedithiocarbamate and piperidinedithiocarbamate complexes of CoII, NiII, CuII and HgII have been studied by thermogravimetry and differential scanning calorimetry. The decomposition intermediates and final products were identified by their X-ray diffraction patterns. The i.r. spectra are discussed in terms of the thermal decomposition pathways.

Preparation and thermal decomposition of solid state lanthanide(III) and yttrium(III) chelates of ethylenediaminetetraacetic acid

Solid state chelates of general formula H[Ln(EDTA)] · nH2O (Ln = trivalent lanthanide (except for promethium) or yttrium; EDTA = ethylenediaminetetraacetate) were prepared. Thermogravimetry, differential thermal analysis. X-ray diffraction and complexometry were used to characterize and study the thermal stability and thermal decomposition of these compounds. © 1993.

The preparation and thermal decomposition of some metal compounds of 4-dimethylaminobenzylidenepyruvate in the solid state

Solid M-DMBP compounds, where M represents Mg(II), Ca(II), Sr(II), Ba(II), Ni(II), Cu(II), Zn(II), Fe(III), La(III), Th(IV), and DMBP is 4-dimethylaminobenzylidenepyruvate, have been prepared. Thermogravimetry-derivative thermogravimetry (TG-DTG), differential scanning calorimetry (DSC) and other methods of analysis have been used to characterize and to study the thermal stability and thermal decomposition of these compounds. © 1995.