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31.
Carp O. Patron L. Ianculescu A. Crisan D. Dragan N. Olar R. 《Journal of Thermal Analysis and Calorimetry》2003,72(1):253-261
The thermal behaviour of two coordination compounds [MnDy(malic)3]· 5H2O and [MnDy(gluconic)3]·12H2O has been studied to evaluate their suitability for dysprosium manganese perovskite ;synthesis. A decomposition scheme is
proposed leading to perovskites with orthorhombic (malic precursor) and hexagonal (gluconic precursor) structures which were
obtained after a heating treatment of 4 h at 1000°C with one-hour plateau at 500°C.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
32.
Carp O Patron L. Marinescu G. Pascu G. Budrugeac P. Brezeanu M. 《Journal of Thermal Analysis and Calorimetry》2003,72(1):263-270
The influence of the coordination architecture (materialized by ligand binding mode and content) on the thermal behaviour
of coordination compounds containing copper, iron and oxalic anion as ligand was investigated. It was established that the
metal-metal connections influence stronger, comparative with ligand content, the stoichiometry of the thermal decompositions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
33.
Carp DJ Bartholomai GB Relkin P Pilosof AM 《Colloids and surfaces. B, Biointerfaces》2001,21(1-3):163-171
The effect of xanthan on foam formation and on physical mechanisms of destabilization involved in the breakdown of foams made from native and denatured soy protein at neutral pH was studied by a bubbling and a whipping-rheological method. Parameters describing foam formation and destabilization by liquid drainage and disproportionation obtained by the two methods showed that the addition of xanthan was accompanied by delayed rates of drainage and disproportionation and reduced foam height decay (collapse). Drainage showed the largest reduction, mainly because of the increased bulk viscosity. In the absence of xanthan, protein denaturation enhanced foam formation and stability against drainage and disproportionation, but increased the collapse of foams. In the presence of xanthan, differences in foam formation and drainage/disproportionation stability between native and denatured soy protein were greatly reduced. However, differences in foam collapse were greatly enhanced. The increased stability of foams in the presence of xanthan could not be explained purely in terms of increased aqueous phase viscosity. More specific interactions of xanthan and soy proteins at the air-water interface influencing the surface rheology, and the protein composition and aggregation, are involved. 相似文献
34.
Patrinoiu G. Patron L. Carp O. Stanica N. 《Journal of Thermal Analysis and Calorimetry》2003,72(2):489-495
Two iron(III) complexes with therapeutically active biguanides - N',N'-anhydrobis-(beta-oxyethyl) biguanide (HMBig), and N',N'-dimethylbiguanide
(HMetf), respectively - [Fe(HMBig)3]Cl3·9H2O (I) and [Fe(HMBig)(HMetf)]Cl3·6H2O (II) - were synthesized and characterized through elemental analysis, electrical conductivity, IR and UV/VIS spectroscopy, measurements
in magnetic field and non-isothermal analysis. In studied complexes the biguanide derivatives act as bidentate ligands through
nitrogen atoms of the iminic groups. Their magnetic moments correspond to iron(III) in the spin quartet ground state. The thermal analysis evidenced an endotherm release of crystallization and coordinated
water molecules. The degradation of the ligand molecules is a complex one, several processes being overlapped. The presence
of biguanidic ligand increase the thermal stability of the coordination compound. The final product of both thermal decompositions
is a-Fe2O3.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
35.
Results are presented on the thermal behaviour of [Fe(III)2Cu(C2C4)2(OH)4(H2O)2] precursor of copper ferrite. An investigation of the decomposition steps and intermediates was followed by a non-isothermal kinetic analysis of the processable steps. 相似文献
36.
L. Patron P. Budrugeac A. Balu Oana Carp L. Diamandescu M. Feder 《Journal of Thermal Analysis and Calorimetry》2007,88(1):273-277
The thermal
behaviour of five polynuclear coordination compounds containing tartaric anion
as ligand, namely (NH4)3[LnFe(C4O6H4)3(OH)3] (Ln=La
and Eu), (NH4)2[PrFe(C4O6H4)3(OH)2] and (NH4)[LnFe(C4O6H4)3(OH)]·3H2O (Ln=Nd and Gd) was investigated. The reaction progress
was studied by TG/DTA and FTIR measurements. Oxalates and oxocarbonates were
identified as intermediates. In the case of Ln=La,
Nd, Pr, Eu and Gd, pure LnFeO3 was obtained as final
decomposition product. The thermal decomposition of Eu-Fe compound, leads
to a mixture of mixed (ortho-ferrite (EuFeO3) and garnet
(Eu3Fe5O12))
and simple oxides (Eu2O3 and
α-Fe2O3). 相似文献
37.
Luminita Patron Oana Carp I. Mindru G. Marinescu J. Hanss A. Reller 《Journal of Thermal Analysis and Calorimetry》2008,92(1):307-312
The thermal behaviour of four coordination compounds (NH4)6[Y3Fe5(C4O5H4)6(C4O5H3)6]·12H2O, (NH4)6[Y3Fe5(C6O7H10)6(C6O7H9)6]·8H2O, (NH4)6[Er3Fe5(C4O5H4)6(C4O5H3)6]·10H2O and (NH4)6[Er3Fe5(C4O6H4)6(C4O6H3)6]·22H2O has been studied to evaluate their suitability for garnet synthesis. The thermal decomposition and the phase composition
of the resulted decomposition compounds are influenced by the nature of metallic cations (yttrium-iron or erbium-iron) and
ligand anions (malate or gluconate). 相似文献
38.
Rodica Olar Mihaela Badea Oana Carp Dana Marinescu Veronica Lazar Carmen Balotescu Anca Dumbrava 《Journal of Thermal Analysis and Calorimetry》2008,92(1):245-251
The investigation concerning the synthesis, spectrochemical and biological properties as well as thermal stability of some tiosulfato-and sulfato copper(II) complexes of type [Cuphen(S2O3)(H2O)n]·mH2O (phen: 1,10-phenanthroline; (1): n=2, m=0; (2): n=2, m=0.5) and respectively [Cuphen(OSO3)(H2O)n] ((3): n=0; (4): n=2) are presented in this paper. The bonding and stereochemistry of the complexes have been characterised by IR and electronic studies. The in vitro qualitative and quantitative assays of the antimicrobial activity of the tested compounds vs. planktonic and adherent Gram negative bacterial strains isolated from different surfaces in the hospital environment demonstrated that all compounds exhibited very good antimicrobial activity vs. Escherichia coli, Klebsiella sp. and Enterobacter sp. with very low M.I.C. values. The thermal analysis has evidenced the thermal intervals of stability and also the thermodynamics effects that accompany them both in synthetic air and argon. The thermal behaviour is complex according to DTG and DSC curves including dehydration as well as thiosulfate and phenanthroline decomposition. 相似文献
39.
Carmen Paraschiv B. Jurca Adelina Ianculescu Oana Carp 《Journal of Thermal Analysis and Calorimetry》2008,94(2):411-416
Two bismuth ferrite potential precursors systems, namely Fe(NO3)3·9H2O-Bi(NO3)3·9H2O-glycine/urea with different metal nitrate/organic compound molar ratios have been investigated in order to evaluate their
suitability as BiFeO3 precursors. The presence into the precursor of both reducing (glycine and urea) and oxidizing (NO3−) components, modifies dramatically their thermal behaviour comparative with the raw materials, both from the decomposition
stoichiometries and temperature occurrence intervals points of view. Also, the thermal behaviour is dependent on the fuel
nature but practically independent with the fuel content. The fuel nature influences also some characteristics of the resulted
oxides (phase composition, morphologies). In the case of the oxides prepared using urea as fuel, a faster evolution toward
a single phase composition with the temperature rise is evidenced, the formation of the BiFeO3 perovskite phase being completed in the temperature range of 500–550°C. 相似文献
40.
Raluca Dumitru Oana Carp P. Budrugeac M. Niculescu E. Segal 《Journal of Thermal Analysis and Calorimetry》2011,103(2):591-596
The authors present their results concerning the decomposition in air of the homopolynuclear coordination compound [CoC2O4·2.5H2O]
n
. In the temperature range 20–300 °C, the heating curves TG, DTG and DTA allowed to evidence three decomposition steps. The
kinetic analysis was performed on the second step which proved to be the only workable one. The application of nonlinear regression
procedure shows that this is a complex process consisting in three successive steps. The checking of the mechanism and corresponding
kinetic parameters for quasi-isothermal data (T = 150 °C) shows that the obtained results could be used for prediction of the thermal behaviour of the investigated compound
in both isothermal and non-isothermal conditions. 相似文献