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1.
Katarína Győryová J. Chomič Erika Szunyogová Lenka Piknová V. Zeleňák Zuzana Vargová 《Journal of Thermal Analysis and Calorimetry》2006,84(3):727-732
Three
new complex compounds of general formula Zn{4-ClC6H3-2-(OH)COO}2⋅L2⋅nH2O
(where L=thiourea (tu), nicotinamide (nam),
caffeine (caf), n=2,3), were prepared and
characterized by chemical analysis, IR spectroscopy and their thermal properties
were studied by TG/DTG, DTA methods. It was found that the thermal decomposition
of hydrated compounds starts with the release of water molecules. During the
thermal decomposition of anhydrous compounds the release of organic ligands
take place followed by the decomposition of salicylate anion. Zinc oxide was
found as the final product of the thermal decomposition performed up to 650°C.
RTG powder diffraction method, IR spectra and chemical analysis were used
for the determination of products of the thermal decomposition. 相似文献
2.
Bernardi M. Inês B. Araújo Vinícius D. Mesquita Alexandre Frigo Geraldo J. M. Maia Lauro J. Q. 《Journal of Thermal Analysis and Calorimetry》2009,95(3):923-928
Novel zinc(II) complex compounds of general formula Zn(C6H5COO)2·L2 (where L=caffeine (caf) and urea (u)) were synthesized and characterized by elemental analysis and IR spectroscopy. The thermal behaviour
of the complexes was studied during heating in air by thermogravimetry. It was found that the thermal decomposition of the
anhydrous Zn(II) benzoate compounds with bioactive ligands was initiated by the release of organic ligands at various temperatures.
On further heating of the compounds up to 400°C the thermal degradation of the benzoate anions took place. Zinc oxide was
found as the final product of the thermal decomposition of all zinc(II) benzoate complex compounds heated to 600°C. Results
of elemental analysis, infrared spectroscopy, mass spectroscopy and thermogravimetry are presented. 相似文献
3.
Szunyogová E. Györyová K. Kováşová J. Juhászová E. 《Journal of Thermal Analysis and Calorimetry》2003,71(3):967-976
Four new complex compounds were prepared by reaction of zinc carboxylate and methyl-3-pyridyl carbamate. The synthesized complex
compounds of the general formula (RCOO)2ZnL2 (RCOO-= HCOO- (form), CH3COO- (ac), CH3CH2CH2COO- (but), (CH3)2CHCOO- (isobut), L= methyl-3-pyridyl carbamate (mpc)) were characterized by chemical analysis, IR spectroscopy and studied by methods of thermal
analysis (TG/DTG, DTA). CH2O, CO2, (CH3)2CO, (C3H7)2CO were found as volatile products of thermal decomposition. ZnO was found as final product of thermal decomposition of the
prepared complexes heated up to 700°C. Mass spectroscopy, X-ray powder diffraction method, IR spectra and chemical analysis
were used for the determination of the thermal decomposition products.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
Andogová E. Györyová K. Nour El-Dien F. A. 《Journal of Thermal Analysis and Calorimetry》2002,69(1):245-253
Four new complex compounds were prepared by the reaction of zinc bromobutyrate and organic ligands. The general formula of the synthetized complex compounds are (2-Brbut)2ZnL and (4-Brbut)2ZnL2nH2O (but=butyrate, L=theobromine (tbr), theophylline (tph), methyl-3-pyridyl carbamate (mpc), n=0-1). The compounds were characterized by chemical analysis and IR spectroscopy. The thermal behaviour of the zinc(II) complexes was studied by thermal analysis. Thermal decomposition in the case of hydrated compounds starts with the release of water molecules. Then molecules of organic ligands and the bromobutyrate anion are released and decomposed. CH3CH2CH=O, CO, CH2=CHCH=O, CH2O and ZnBr2 were found as gaseous products of thermal decomposition during heating up to 700°C. IR, mass spectroscopy, X-ray powder diffraction and chemical analysis were used for the determination of solid and gaseous intermediates and products of the thermal decomposition.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
5.
Györyová K. Kovářová J. Andogová E. Zeleňák V. Nour El-Dien F. A. 《Journal of Thermal Analysis and Calorimetry》2002,67(1):119-128
Zinc carboxylate complexes with N-donor ligands exhibit antimicrobial and antifungal effects. The preparation and thermal properties of complex compounds Zn(isobut)2 and Zn(isobut)2L(isobut=(CH3)2CHCOO–, L=papaverine — pap, phenazone — phen) are described in this paper. The newly synthesized compounds were characterized by elemental analysis, IR spectroscopy and TG/DTG, DTA methods.During the thermal treatment it was found that the release of organicligands (pap, phen) was followed by pyrolysis of zinc(II) isobutyrate. (C3H7)2CO and CO2 were found as gaseous products and zinc oxide as the final product of thermal decomposition. Gaseous and solid products of thermal decomposition were confirmed by chemical analysis, IR spectra and X-ray powder diffraction.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
6.
Zuzana Bujdošová Katarína Györyová Daniela Hudecová Jana Kovářová Ladislav Halás 《Chemical Papers》2010,64(5):584-591
New zinc(II) 4-chloro- and 5-chlorosalicylate complex compounds of the general formula ((4- or 5-Cl)C6H3(2-OH)COO)2Zn · L
n
(where L = methyl 3-pyridylcarbamate, phenazone; n = 2, 4) were prepared and characterized by elemental analysis, thermal analysis (TG/DTG, DTA), and IR spectroscopy. During
thermal decomposition, mpc, phen, chlorosalicylic acid, chlorophenol, carbon dioxide, and carbon monoxide were released. Volatile
products of the thermal decomposition were confirmed by mass spectrometry. The final solid product of the thermal decomposition
up to 700°C was zinc oxide or metallic zinc. Antimicrobial activity of the compounds prepared was tested against various strains
of bacteria, yeasts and filamentous fungi. The highest antimicrobial effect was determined against the G+ bacteria S. aureus. 相似文献
7.
YANG De-Jun LI Xu LI Qiang-Guo LI Ai-Tao YE Li-Juan JIANG Jian-Hong LIU Yi 《中国化学》2008,26(12):2155-2160
The product from reaction of lanthanum chloride heptahydrate with salicylic acid and thioproline, [La(Hsal)2•(tch)]•2H2O, was synthesized and characterized by IR, elemental analysis, molar conductance, thermogravimatric analysis and chemistry analysis. The standard molar enthalpies of solution of LaCl3•7H2O (s), [2C7H6O3 (s)], C4H7NO2S (s) and [La(Hsal)2•(tch)]•2H2O (s) in a mixed solvent of absolute ethyl alcohol, dimethyl sulfoxide (DMSO) and 3 mol•L-1 HCl were determined by calorimetry to be [LaCl3•7H2O (s), 298.15 K]=(-102.36±0.66) kJ•mol-1, [2C7H6O3 (s), 298.15 K]=(26.65±0.22) kJ•mol-1, [C4H7NO2S (s), 298.15 K]=(-21.79±0.35) kJ•mol-1 and {[La(Hsal)2•(tch)]•2H2O (s), 298.15 K}=(-41.10±0.32) kJ•mol-1. The enthalpy change of the reaction LaCl3•7H2O (s)+2C7H6O3 (s)+C4H7NO2S (s)=[La(Hsal)2•(tch)]•2H2O (s)+3HCl (g)+5H2O (l) (Eq. 1) was determined to be =(41.02±0.85) kJ•mol-1. From date in the literature, through Hess’ law, the standard molar enthalpy of formation of [La(Hsal)2•(tch)]•2H2O (s) was estimated to be {[La(Hsal)2•(tch)]•2H2O (s), 298.15 K}=(-3017.0±3.7) kJ•mol-1. 相似文献
8.
Zuzana Bujdošová Katarína Győryová Jana Kovářová Daniela Hudecová Ladislav Halás 《Journal of Thermal Analysis and Calorimetry》2009,98(1):151-159
New zinc(II) salicylate complex compounds of general formula (X-C6H3-2-(OH)COO)2Zn · Ln · xH2O (where X = H, 5-Cl; L = theophylline, urea; n = 2, 4; x = 1, 2, 4) were prepared and their thermal, spectral and biological properties were studied. It was found that the thermal
decomposition of hydrated compounds starts with the release of water. During the thermal decomposition of anhydrous compounds,
the release of salicylic acid, theophylline, urea, CO2, H2O and C6H5Cl takes place. Zinc oxide was found as the final product of the thermal decomposition heated up to 900 °C. The complexes
were tested against bacteria, yeasts and filamentous fungi. The highest biological activity show 5-chlorosalicylate compounds. 相似文献
9.
Katarína Homzová Katarína Győryová Zuzana Bujdošová Daniela Hudecová Mária Ganajová Zuzana Vargová Jana Kovářová 《Journal of Thermal Analysis and Calorimetry》2014,116(1):77-91
New zinc(II) 4-hydroxybenzoate complex compounds with general formula [Zn(4-OHbenz)2Ln]·xH2O, where 4-OHbenz = 4-hydroxybenzoate; L = isonicotinamide, N-methylnicotinamide, N,N-diethylnicotinamide, thiourea, urea, phenazone, theophylline, methyl-3-pyridylcarbamate; n = 2, 3; x = 0–3, 5, were synthesized and characterised by elemental analysis, thermal analysis and IR spectroscopy. The thermal behaviour of the prepared compounds was studied by TG/DTG and DTA methods in argon atmosphere. The thermal decomposition of hydrated compounds started with dehydration. During the thermal decomposition, organic ligand, carbon monoxide, carbon dioxide and phenol were evolved. The final solid product of the thermal decomposition was zinc or zinc oxide. The volatile gaseous product, solid intermediate products and the final product of thermal decomposition were identified by IR spectroscopy, mass spectrometry, qualitative chemical analyses and X-ray powder diffraction method. The antimicrobial activity of zinc(II) carboxylate compounds was tested against various strains of bacteria, yeasts and filamentous fungi (S. aureus, E. coli, C. parapsilosis, R. oryzae, A. alternata, M. gypseum). The presence of zinc in complexes led to the increase in their antimicrobial activity in comparison with free 4-hydroxybenzoic acid. 相似文献
10.
D. Czakis-Sulikowska J. Radwańska-Doczekalska A. Czylkowska M. Markiewicz A. Broniarczyk 《Journal of Thermal Analysis and Calorimetry》2006,86(2):327-335
New mixed-ligand complexes with empirical
formulae: Mn(2-bpy)1.5L2·2H2O,
M(2-bpy)2L2·3H2O
(M(II)=Co, Cu), Ni(2-bpy)3L2·4H2O
and M(2,4’-bpy)2L2·2H2O
(where 2-bpy=2,2’-bipyridine, 2,4’-bpy=2,4’-bipyridine; L=HCOO– ) have been
obtained in pure solid-state. The complexes were characterized by chemical
and elemental analysis, IR and VIS spectroscopy, conductivity (in methanol
and dimethylsulfoxide). The way of metal-ligand coordination discussed. The
formate and 2,4’-bpy act as monodentate ligands and 2-bpy as chelate
ligand. The new complexes with ligand isomerism were identified. During heating
the complexes lose water molecules in one or two steps. Thermal decomposition
after dehydration is multistage and yields corresponding metal oxides as final
products. A coupled TG-MS system was used to analysis principal volatile thermal
decomposition (or fragmentation) products of Ni(2,4’-bpy)2(HCOO)2·2H2O under dynamic air or argon atmosphere. 相似文献
11.
D. Czakis-Sulikowska A. Czylkowska J. Radwańska-Doczekalska R. Grodzki E. Wojciechowska 《Journal of Thermal Analysis and Calorimetry》2007,90(2):557-564
New mixed-ligands complexes with empirical formulae: M(2,4′-bpy)2L2·H2O (M(II)Zn, Cd), Zn(2-bpy)3L2·4H2O, Cd(2-bpy)2L2·3H2O, M(phen)L2·2H2O (where M(II)=Mn, Ni, Zn, Cd; 2,4′-bpy=2,4′-bipyridine, 2-bpy=2,2′-bipyridine, phen=1,10-phenanthroline, L=HCOO−) were prepared in pure solid state. They were characterized by chemical, thermal and X-ray powder diffraction analysis, IR
spectroscopy, molar conductance in MeOH, DMF and DMSO. Examinations of OCO− absorption bands suggest versatile coordination behaviour of obtained complexes. The 2,4′-bpy acts as monodentate ligand; 2-bpy and phen as chelating ligands. Thermal studies were performed in static air atmosphere. When the temperature raised the dehydration
processes started. The final decomposition products, namely MO (Ni, Zn, Cd) and Mn3O4, were identified by X-ray diffraction. 相似文献
12.
Four new mixed ligand complexes were prepared by the reaction of title metal dichloroacetates and 2,4'-bipyridine. The general
formulae of synthesized compounds are M(2,4'-bpy)2(CCl2HCOO)2·nH2O (where M(II)=Mn, Co, Ni, Cu; 2,4'-bpy=2,4'-bipyridine, n=2 or 4). The complexes have been isolated from aqueous media and characterized by chemical analysis, molar conductance (in
MeOH, DMSO and DMF), magnetic, IR and VIS spectral studies. The nature of metal(II)-ligand coordination is discussed. The
thermal behaviour of obtained complexes was studied by thermal analysis and TG-MS techniques in air. IR, X-ray powder diffraction
and thermoanalytical data were used for the determination of solid intermediate products of the thermal decomposition. The
principal volatile products of thermal decomposition of complexes were proved by mass spectroscopy: H2O+, CO+
2, HCl+
2, Cl+
2, NO+ and other.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
13.
Annamária Krajníková Katarína Győryová Daniela Hudecová Jana Kovářová Zuzana Vargová 《Journal of Thermal Analysis and Calorimetry》2011,105(2):451-460
New zinc(II) 2-bromobenzoate complex compounds with general formula Zn(2-BrC6H4COO)2·nL·xH2O (where L = urea, nicotinamide, N-methylnicotinamide, N,N-diethylnicotinamide, isonicotinamide, phenazone n = 0–2, x = 0–2) were prepared and characterized by elemental analysis, IR spectroscopy and thermal analysis. The thermal decomposition
of hydrated compounds started with dehydration process. During the thermal decomposition organic ligand, carbon dioxide and
bis(2-bromophenyl)ketone were evolved. The solid intermediates and volatile products of thermal decomposition were proved
by IR spectroscopy and mass spectrometry. The final solid product of the thermal decomposition heated up to 1073 K was zinc
oxide. Antimicrobial activity of the prepared compounds was tested against various strains of bacteria, yeasts and filamentous
fungi (E. coli, S. aureus, C. albicans, R. oryzae, A. alternate and M. gypseum). It was found that the selected bacteria were more sensitive to the studied zinc(II) complex compounds than the yeast and
the filamentous fungi. 相似文献
14.
Tongshan Sun Yuting Zhao Jaihui Jin Daqing Wang 《Journal of Thermal Analysis and Calorimetry》1995,45(1-2):317-327
Four complexes of rare earth bromides with amino acids, REBr3·3L·3H2O (RE=La, Nd;L=glycine or alanine) were prepared and characterized by means of chemical analysis, elemental analysis, molar conductivity, thermogravimetry, IR spectra and X-ray diffraction. Their thermal decomposition kinetics from ambient temperature to 500°C were studied by means of TG-DTG techniques under non-isothermal conditions. The kinetic parameters (activation energyE and pre-exponential constantA) and the most probable mechanisms of thermal decomposition were obtained by using combined differential and integral methods. The thermal decomposition processes of these complexes are distinguished as being of two different types, depending mainly on the nature of the amino acid. 相似文献
15.
T. Premkumar S. Govindarajan W.-P. Pan R. Xie 《Journal of Thermal Analysis and Calorimetry》2003,74(1):325-333
Some new transition metal imidazolehydrogendicarboxylate hydrates of empirical formula M(Himdc)2·nH2O (H
2
imdc=4,5-imidazoledicarboxylic acid), where n=2 for M=Mn, Ni, Zn, Cd and n=3 for M=Co, have been prepared in aqueous solution. The compounds have been characterized by analytical, electronic and IR spectroscopic,
thermal analysis and X-ray powder diffraction studies. Electronic spectroscopic data suggest that the Co and Ni compounds
are of spin free (high spin) type with octahedral geometry. For these compounds, the IR bands in the region 1750-1710 cm-1 has been assigned to stretching vibrations of the non-ionized carboxylic group, confirming that the ligand is monoionized.
IR spectra also suggest the unidentate co-ordination behaviour of carboxylate (vasy =1570 and vsym=1390 cm-1) groups of the imidazoledicarboxylate monoanion. The thermal behaviour of these compounds has been studied by simultaneous
TG-DTA techniques. All of these compounds are dihydrates except cobalt which is a trihydrate. Thermal decomposition studies
show that they lose two water molecules endothermally in the range 200-270°C to give their anhydrous compounds, indicating
that these water molecules are coordinated to the metal. The anhydrous compounds further decompose exothermally in the range
300-620°C to leave the respective metal oxides via the metal oxalate intermediates. Whereas the manganese compound undergoes
pyrolytic cleavage in a single step to give the manganese carbonate as the final residue. Isomorphic nature of these compounds
is evident from XRD data. Six-coordination for the metal atoms has been proposed based on the thermal analysis, visible and
IR spectroscopic results.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
16.
Olczak-Kobza M. Czylkowski R. Karolak-Wojciechowska J. 《Journal of Thermal Analysis and Calorimetry》2003,74(3):895-904
Mixed complexes of the type: Zn(Hsal)2(Him)2, Zn(Hsal)2(Him)5, Zn(Hsal)2(4-MeHim)2 and Zn(Hsal)2(1,2-diMeim)2 (where Hsal=OHC6H4COO-, Him=imidazole, 4-MeHim=4-methylimidazole, 1,2-diMeim=1,2-dimethylimidazole) have been synthesized. The application of chemical, thermal and X-ray methods has enabled us to analyze
the complexes and their sinters. The gaseous products of pyrolysis of Zn(Hsal)2(Him)2 and Zn(Hsal)2(4-MeHim)2 have been investigated. Thermal decomposition pathways have been postulated for synthesized complexes. The molecular structures
of the Zn(Hsal)2(Him)2 and Zn(Hsal)2(1,2-diMeim)2 have been solved. 相似文献
17.
Czakis-Sulikowska D. Malinowska A. Łuczak A. 《Journal of Thermal Analysis and Calorimetry》2004,78(2):461-471
Two lactates and four new mixed ligand complexes with formulae Co(lact)2·2H2O, Ni(lact)2·3H2O, Co(4-bpy)(lact)2, Co(2,4'-bpy)2(lact)2, Ni(4-bpy)(lact)2·2H2O and Ni(2,4'-bpy)2(lact)2 (where 4-bpy=4,4'-bipyridine, 2,4'-bpy=2,4'-bipyridine, lact=CH3CH(OH)COO-) were isolated and investigated. The thermal behaviour of compounds was studied by thermal analysis (TG, DTG, DTA). In the
case of hydrated complexes thermal decomposition starts with the release of water molecules. The compounds decompose at high
temperature to metal(II) oxides in air. A coupled TG-MS system was used to analyse the principal volatile products of thermolysis
and fragmentation processes of obtained complexes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
18.
C. Menapace I. Lonardelli A. Molinari 《Journal of Thermal Analysis and Calorimetry》2010,101(3):815-821
New complexes of type [Cu(HTBG)2]Cl2 (1), [Cu(TBG)2]·3H2O (2) and [CuL]·nH2O (3) L:L1, n = 2 and (4) L:L2, n = 1 (HTBG: 2-tolylbiguanide, L1 and L2: ligands resulted from 2-tolylbiguanide, ammonia/hydrazine and formaldehyde one pot condensation) were synthesised and characterised.
The features of complexes have been assigned from microanalytical, IR and UV–Vis data. Redox behaviour was established by
cyclic voltammetry. The in vitro qualitative and quantitative antimicrobial activity assays showed that the complexes exhibited
variable antimicrobial activity against Gram-negative and Gram-positive strains isolated from the hospital environment. The
thermal analyses have evidenced the thermal intervals of stability and also the thermodynamic effects that accompany them.
After water elimination, complexes have a similar thermal behaviour. Processes as water elimination, melting, chloride anion
removal as well as oxidative degradation of the organic ligands were observed. The final product of decomposition was copper
(II) oxide. 相似文献
19.
New zinc acetate based complex compounds (of general formula Zn(CH3COO)2·1?2L·nH2O) containing one or two molecules of urea, thiourea, coffeine and phenazone were prepared namely: Zn(CH3COO)2·2.5H2O, Zn(CH3COO)2·2u·0.5H2O, Zn(CH3COO)2·tu·0.5H2O, Zn(CH3COO)2·2tu, Zn(CH3COO)2·cof·2.5H2O, Zn(CH3COO)2·2cof·3.5H2O, Zn(CH3COO)2·2phen·1.5H2O. The compounds were characterized by IR spectroscopy, chemical analysis and thermal analysis. Thermal analysis showed that no changes in crystallographic modifications of the compounds take place during (heating in nitrogen before) the thermal decompositions. The temperature interval of the stability of the prepared compounds were determined. It was found that the thermal decomposition of hydrated compounds starts by the release of water molecules. During the thermal decomposition of anhydrous compounds in nitrogen the release of organic ligands take place followed by the decomposition of the acetate anion. Zinc oxide and metallic zinc were found as final products of the thermal decomposition of the zinc acetate based complex compounds studied. Carbon dioxide and acetone were detected in the gaseous products of the decomposition of the compounds if ZnO is formed. Carbon monoxide and acetaldehyde were detected in the gaseous products of the decomposition, if metallic Zn is formed. It is supposed that ZnO and Zn resulting from Zn acetate complex compounds here studied, possess different degree of structural disorder. Annealing takes place by further heating above 600°C. 相似文献
20.
Gómez-Carracedo A. Alvarez-Lorenzo C. Gómez-Amoza J. L. Concheiro A. 《Journal of Thermal Analysis and Calorimetry》2003,73(2):587-596
New zinc(II) propionate complexes (CH3CH2COO)2Zn·Ln·xH2O, where n=1-2, x=0 or 2, were prepared by reaction of zinc(II) propionate with heterocyclic ligands (L=theophylline, nicotinamide, methyl-3-pyridyl carbamate) and their thermal properties were studied. The prepared complex compounds were characterized by elemental analysis and IR spectra. TG/DTG and DTA measurements of the prepared compounds were performed in the air atmosphere under dynamic conditions. The thermal decomposition can be characterized as a multi-step process. The first step is attributed to the elimination of water or N-donor ligand molecules. It is followed by the decomposition of propionate anion when diethyl ketone and carbon dioxide were released. Zinc oxide was found as a final product of the thermal decomposition of the complex compounds under study. The volatile intermediate products of the thermal decomposition of zinc(II) propionate complexes were identified by IR-spectroscopy, qualitative chemical analyses and final solid product by X-ray powder diffraction method. Moreover, IR spectra suggest monodentate coordination of propionate anion to zinc. The complexes were tested against bacteria and filamentous fungi and show both antimicrobial activity and fungistatic effect towards pathogens as well as probiotic activity towards Lactobacillus paracasei. 相似文献