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Acta Veterinaria Hungarica
Authors: Károly Erdélyi, János Gál, László Sugár, Krisztina Ursu, Petra Forgách, Levente Szeredi, and Theodora Steineck

Oval, firm, cutaneous tumours with a rough, hairless, pigmented surface, exhibiting a moderately pronounced papillary structure were detected on the abdominal skin of two young red deer ( Cervus elaphus ). One animal was shot in Lower Austria in 2004, the other at a deer farm in Hungary in 2007. Histological examination of both samples classified the tumours as fibropapillomas, showing marked proliferation of fibroblasts and connective tissue, accompanied by hyperkeratosis, parakeratosis and acanthosis of the overlaying epidermis, and occasional foci of inflammation. The distribution of cytokeratin and vimentin was characterised in the lesion. The presence of papillomavirus (PV) antigen was demonstrated by immunohistochemistry in both cases. Papillomavirus-specific DNA was successfully amplified by PCR from one sample. The obtained partial nucleotide sequence of the L2 ORF exhibited the highest critical identity values with the homologous regions of Delta-papillomaviruses, especially the Roe deer papillomavirus (93%). Phylogenetic analysis of the partial L2 ORF sequence alignment of 10 papillomaviruses by both neighbour-joining and maximum parsimony method confirmed that the Red deer PV is very closely related to the Western roe deer papillomavirus (CcPV1).

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Abstract  

Schiff bases obtained by the condensation of 2-amino-5-mercapto-1,3,4-thiadiazole with 2,4-pentandione or 1-phenyl-1,3-butandione were synthesized and characterized in order to obtain polydentate ligands HL1 and HL2, respectively. The complexes with these ligands of the type M(L)Cl·nH2O [(1) M:Ni, L:L1, n = 0.5; (3) M:Ni, L:L2, n = 0.5]; [(2) M:Cu, L:L1, n = 1; (4) M:Cu, L:L2, n = 0] were also synthesized and characterized. The modifications evidenced in IR spectra of complexes were correlated with the presence of monodeprotonate Schiff bases. The electronic spectra display the characteristic pattern of square-planar stereochemistry. The in vitro qualitative and quantitative antimicrobial activity assays showed that the new complexes exhibited variable antimicrobial activity. The thermal analyses have evidenced the thermal intervals of stability and also the thermodynamic effects that accompany them. Schiff bases and 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.

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Direct somatic embryo formation (without intervening callus) from garlic clove basal tissue was induced in which the influence of plant growth regulators (PGRs) on various explants was examined. Medium added with 2.0 mg/l 6-benzylaminopurine (BAP) and 0.5 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) were the most effective PGR combination for somatic embryo induction. It induced embryos directly in 85.5% of the basal clove explant. Callus induction was also obtained from other parts of explant and 2.0 mg/l 2,4-D induced callusing in 86.5% of the inoculated explants. Protein, amino acid and alliin content were measured in callus and in embryos. Somatic embryos had more soluble protein and free amino acid compared to callus. HPTLC analysis revealed that alliin was significantly high in somatic embryos compared to undifferentiated callus tissue; the content was even more in older embryos. The present study of Allium indicates that the event of morphogenetic development including in vitro embryogeny can effectively be analysed by monitoring the changes of biochemical profiles.

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Реэюме  

В работе построены раэложения тождественного оператора в пространстве L p(I d) в кратные ряды иэ ортопроекционных операторов на вэаимно ортогональные подпространства кусочно-полиномиальных функции, частным случаем которых является ряд Хаара. Юстановлены оценки норм в L p(I d) соответствуюших проекции. С их помошью получены оценки колмогоровского n-поперечника в пространстве L 2(I d) для единичных щаров пространств Никольского и QBесова функции, удовлетворяюших смещанным условиям Гёльдера, даюшие порядок тои величины.

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Abstract  

The thermal decomposition of three new reagent cyclohexylamine-p-tolylglyoxime (L1H2), tertiarybutyl amine-p-tolylglyoxime (L2H2) and secondary butylamine-p-tolylglyoxime (L3H2 and their Co-complexes were studied by both isothermal and nonisothermal methods. As expected, the complex structure of Co-complexes, different steps with different activation energies were realized in decomposition process. Model-fitting and model-free kinetic approaches were applied to nonisothermal and isothermal data. The kinetic triplet (f(α), A and E) related to nonisothermal model-fitting method can not be meaningfully compared with values obtained from isothermal method. The complex nature of the multi-step process of the studied compounds was more easily revealed using a wider temperature range in nonisothermal isoconversional method.

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Reactions of divalent transition metal halides with 3,5-dimethyl-1-(hydroxymethyl)-pyrazole

Part 23. Transition metal complexes with pyrazole-based ligands

Journal of Thermal Analysis and Calorimetry
Authors: V. Leovac, R. Petković, A. Kovács, G. Pokol, and Katalin Szécsényi

Abstract  

Factors determining the complex formation reaction of copper(II), nickel(II) and cobalt(II) chloride and copper(II) bromide with 3,5-dimethyl-1-(hydroxymethyl)-pyrazole (HL) has been studied. Depending on experimental conditions, complexes with different composition were obtained: [CuCl2(dmp)]2 (I), [CuCl2(dmp)2]2 (II), [CoCl2(dmp)2] (III) (dmp=3,5-dimethylpyrazole), [CuBr(L)]2 (IV), [CoCl(L)(EtOH)]4 (V) and [NiCl(L)(EtOH)]4 (VI). The compounds were characterized by FTIR spectroscopy, solution conductivity and magnetic measurements. The crystal structure of [CoCl(L)(EtOH)]4 has been determined by single crystal X-ray diffraction. The thermal decomposition of the compounds was studied and found to be continuous for all of the compounds. The desolvation mechanism of [MCl(L)(EtOH)]4 (M=Co(II), Ni(II)) is explained on the basis of the route of complex formation of CoCl2 with HL.

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Ziegler-Natta catalytic systems

Calorimetric and DFT study on TiCl4-Lewis base interactions

Journal of Thermal Analysis and Calorimetry
Authors: L. Cavallo, J. Ducéré, Rosalisa Fedele, A. Melchior, Maria Mimmi, G. Morini, F. Piemontesi, and Marilena Tolazzi

Abstract  

A calorimetric investigation on the reactions of TiCl4 with phthalates in 1,1,2,2-tetrachloroethane (TCE) is presented in order to better understand the complex interactions present in Ziegler-Natta catalytic systems. The Lewis bases diethyl isophthalate (L1), diethyl terephthalate (L2) and the ortho-isomer diethylphthalate (L3), have been chosen to study how the substituent positions could influence the energy and the stoichiometry of the complexation reactions. FTIR spectroscopy was used to obtain information on the coordination mode of the ligands and diffusion measurements by NMR was carried out to verify the presence of oligo-or polymeric species. Experimental results were compared with theoretical calculations based on Density Functional Theory (DFT).

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Abstract  

Thermal decomposition of managanese hexa(formato)ferrate(III)hexahydrate, i.e., Mn3[Fe(HCOO)6l2·6H2O has been studied upto 700°C in static air atmosphere employing TG, DSC, XRD, IR and Mössbauer spectroscopic techniques. The anhydrous complex decomposed directly into ferric oxide and manganese carbonate in successive stages without undergoing reduction to iron(II) intermediate. Finally a solid state reaction between Fe2O3 and manganese carbonate leads to the formatin of manganese ferrte (MnFe2O4) at a temperature (655°C) much lower than for ceramic method. A saturation magnetization value (4 Ms) of 2550 Gauss makes MnFe2O4 suitable for functioning at high frequencies.

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Journal of Thermal Analysis and Calorimetry
Authors: Lenka Findoráková, Katarína Győryová, Jana Kovářová, V. Balek, F. Nour El-Dien, and L. Halás

Abstract  

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.

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Abstract  

The carboxylato–Cu(II) complexes of type [Cu2(RCOO)4] and their benzothiazole adducts [Cu2(RCOO)4bt2] (bt = benzothiazole, R = CH3(CH2)n−2, n = 12, 14, 16, 18) form the main objectives of this study. The studied carboxylato–Cu(II) complexes are formed from dimeric units to polymeric chains (chromofor CuO5). The structural changes are due to coordination of ligand (benzothiazole). The polymeric chains of carboxylato–Cu(II) complexes degraded to discrete centrosymetric tetracarboxylate-bridged dimmers (chromofor CuO4N). These prepared compounds [Cu2(RCOO)4] and [Cu2(RCOO)4L2] were submitted to measurements relating to spectral (IR, UV–Vis) and thermal properties (TG, DTA, DSC).

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