Elena Cristurean

Thermal stability of some azo-derivatives and their complexes

Abstractthis paper deals with the first investigation concerning the thermal stability of two 1-(2-benzothiazolyl)-3-methyl-4-azo-pyrazil-5-one derivatives and their Cu(II) coordination compounds of type ((C4H9)4N)2[Cu(L)2]. The thermal decomposition steps were established.

Thermal Stability of Some Polynuclear Coordination Compounds in the Systems Ln(III)—Co(II)—Oxalate

This paper reports an investigation of the thermal stabilities of the class of coordination compounds containing lanthanide ions Ln(III) (Ln=La, Sm, Eu, Dy, Er), Co(II) ions and oxalate anions C2O42−. The thermal decomposition steps were identified, and in some cases the values of the non-isothermal kinetic parameters were determined.

Soft chemical synthesis and characterisation of some substituted ferrites

Substituted ferrites with the chemical composition MxFe1−xFe2O4·nH2O (M: Mn(II), x: 0.35, n: 0.4; M: Ni(II), x: 0.38, n: 1; M: Zn(II), x: 0.45, n: 0.35) have been prepared by a soft chemical method using as starting materials magnetite and suitable acetates. These compounds have been characterised by elemental chemical analysis, thermal analysis, IR spectroscopy, X-ray diffraction on powder, transmission electron microscopy studies as well as Mossbauer spectroscopy and magnetic measurements at room temperature. The X-ray diffraction study indicates that the substituted ferrites adopt a cubic structure and the size of particles determined from the diffraction peak is fairly close to that indicated for agglomerates by transmission electron microscopy. The magnetic methods agree to the substitution of Fe(II) in the octahedral positions preserving the inversed spinel structure.

Thermal Stability and Non-isothermal Decomposition Kinetics. Heteropolynuclear compounds of Cu(II)

Data concerning the thermal behaviour of four heteropolynuclear compounds with the general formula [CuML(CH3COO)3] whereM=Ni(II), Zn(II), Mn(II) and Co(II); LH=2-amino-5-mercapto-1,2,3-thiadiazole were obtained. For the kinetically workable decomposition steps the values of the kinetic parameters were estimated.

Magnetic and Morphologic Characterisation of Some Substituted Ferrites Synthesised by a Non-Conventional Method

Substituted ferrites with the chemical composition MxFe1-xFe2O4·nH2O (M: Mn(II), x:0.35, n: 0.4; M: Ni(II), x:0.38, n: 1; M: Zn(II), x:0.45, n: 0.35) have been prepared by a soft chemical method using as starting materials magnetite and suitable acetates. These compounds have been characterised X-ray diffraction on powder and magnetic measurements at room temperature.