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Abstract  

Extraction of microamounts of strontium and barium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B) in the presence of polyethylene glycol PEG 600 (L) has been investigated. The equilibrium data have been explained assuming that the complexes HL+, H2L2+, ML2+ and MHL3+ (M2+ = Sr2+, Ba2+) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined. It was found that in water-saturated nitrobenzene the stability constant of the BaL2+ cationic complex species is essentially higher than that of the complex SrL2+.

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Abstract  

The kinetics of the oxidation-reduction reaction between N,N-diethylhydroxylamine (DEHAN) and vanadium(V) in nitric acid media have been studied by spectrophotometry at 13.5 °C. The rate equation of reaction was found to be -d[V(V)]/dt = k [V(V)] [DEHAN] by investigating the influence of the concentration, acidity, ionic strength and the effect of initial concentration on reaction. The rate constant of reaction k = 36.38 mol/l-2 ·min-1 when = 2.0 mol/l. A possible mechanism of reaction has been suggested on the basis of chemical analysis, 1 H NMR and ESR spectra.

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Abstract  

The compounds ML2(NCS)2, (M(II)=Mn, Co), FeL2(NCS)22H2O, NiL3 NCS)23H2O (L=2,2'-bipyridine, 2-bipy) MX2(NCS)22H2O (M(II)=Mn, Fe; X=4,4'-bipyridine, 4-bipy) have been prepared and their IR spectra and molar conductivity studied. The thermal decomposition of the complexes was studied under non-isothermal conditions in air. During heating the hydrated complexes lose crystallization water molecules in one or two steps and then decompose via different intermediate compounds to the oxides Mn3O4, Fe2O3, CoO, NiO.

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Abstract  

The results of an investigation concerning there action between 1,2-propanediol and Co(NO3)2⋅ 6H2O, leading to a complex containing the lactate anion (L) as ligand are presented. The obtained solid homopolynuclear coordination compound[Co2(OH)2L2(H2O)2⋅0.5H2O]n, has been investigated by thermal analysis, electronic and IR spectroscopy and magnetic methods. Cobalt oxide obtained by thermal decomposition of this coordinative compound was characterized by IR and X-ray spectroscopy.

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The study reported in the paper investigates the structure of L2 self-corrections in the speech of 30 Hungarian learners of English and 10 Hungarian native speakers. The aim of the research is to examine what the well-formedness of the corrections, the use of editing terms, the placement of cut-off points and the effect of the participants' level of proficiency on the structure of self-repairs reveal about the psycholinguistic processes of speech production. The results of the study lend additional support for modular models of speech production (e.g., Levelt 1983, 1989; Levelt et al. 1999) and reveal an important role of pragmatic constraints in psycholinguistic processing.

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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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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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The aim of the present article is to give an overview of the most important approaches to translation competence. As the term ‘competence’ is used in a somewhat arbitrary way in translation studies, psychological approaches to competence are reviewed first. Then some influential translation competence models are presented and analyzed. Translation competence models are classified into three categories based on Pym (2003). The outlined translation competence models are also related to the psychological concepts of competence described at the beginning of the study. Finally, recurrent issues related to translation competence are identified and discussed briefly. These issues involve the relationship between language competence and translation competence; the existence of a separate transfer component of competence, the status of natural translation and the differences between L1→L2 and L2→L1 translation. It is concluded that none of the models of translation competence is inherently better than the others. It is always the purpose of a given piece of research or project that should determine the type of competence model to be adopted.

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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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Journal of Thermal Analysis and Calorimetry
Authors: Rodica Olar, Mihaela Badea, Dana Marinescu, Emilia Iorgulescu, Eliza Frunza, Veronica Lazar, and Carmen Chifiriuc

Abstract  

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.

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