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Acta Veterinaria Hungarica
Authors: András Gáspárdy, Gil Ismach, Árpád Bajcsy, Gyula Veress, Szilárd Márkus, and István Komlósi

Goodling, R. C., Rogers, G. W., Cooper, J. B. and Rune, B. (2000): Heritability estimates for electrical conductivity of milk and correlations with predicted transmitting abilities for somatic cell scores. J. Dairy Sci. 83 , 71 (Abstract

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The complexes of Zn, Cd and Hg of isatin isonicotinoyl hydrazone were prepared at two differentpHs. Their thermal studies (TG, DTG and DTA) have been made and the DC electrical conductivity of compressed powder samples as a function of temperature was investigated. The activation energies (ΔE) were calculated for the ligand and the complexes which showed that the ligand has a lower value of ΔE than the complexes. The magnitude of ΔE was found to be affected by the nature of the metal and thepH of preparation.

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CrIII, MnII and UO2 II amino alcohol complexes were prepared and analyzed. The IR spectra proved that the ligation occurs via oxygen and nitrogen atoms. The nujol mull electronic absorption spectra joined with the room temperature magnetic moment values proved that the complexes are of Oh geometry. The thermal behaviour of the complexes was studied by DTA and TG techniques. The mechanism of the decomposition was suggested. The thermodynamic parameters of the decomposition were evaluated and discussed. The entropy of activation changes, S*, showed that the transition states are more ordered than the reacting complexes. The D.C. electrical conductivity measurements of Cr- and Mn-amino alcohol complexes are of semiconductor behaviour. Empirical equations were deduced for the conduction of the investigated complexes.

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Several experimental techniques were used to characterise the physicochemical properties of the TbBr3-NaBr system. The phase diagram determined by DSC, exhibits an eutectic and a Na3TbBr6 stoichiometric compound that decomposes peritectically (759 K) shortly after a solid-solid phase transition (745 K). The eutectic composition, x(TbBr3)=39.5 mol%, was obtained from the Tamman method. This mixture melts at 699 K. With the corresponding enthalpy of about 16.1 kJ mol-1. Diffuse reflectance spectra of the pure components and their solid mixtures (after homogenisation in the liquid state) confirmed the existence of new phase exhibiting its own spectral characteristics, which may be possibly related to the formation of Na3TbBr6 in this system. Additionally, the electrical conductivity of TbBr3-NaBr liquid mixtures was measured down to temperatures below solidification over the whole composition range.

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The electrical conductivities and the electronic, IR and NMR spectra were measured for some ethyl cyanoacetate phenylhydrazone derivatives and their lanthanide complexes in the temperature range 20–200‡C. Semiconducting behaviour was detected for these systems (positive dσ/dT). A correlation was established between the electrical properties and the structures of the free ligand molecules and their complexes. The mechanism of the conduction process was evaluated. The electronic absorption spectra in ethanol were measured and are discussed. Elemental analyses were performed and the IR and NMR spectra (of the diamagnetic complexes) were measured to throw more light on the structures of these complexes.

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properties, structure, and electrical conductivity of LnX 3 – MX systems. It reports the thermodynamic and transport properties of DyBr 3 – RbBr binary system. The only literature information on this system was the graphic form of the phase diagram reported

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AgI–Ag 2 O–V 2 O 5 glass matrix affects the E c and E s values significantly [ 20 ]. In the present work, we have discussed a new and extremely sensitive method, viz. electrical conductivity versus temperature cycles at various controlled

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Electrical conductivity of some dibenzoylmethane arylhydrazones (DBMAH) were measured during heating and reheating runs. The observed variation of the conductance of the polycrystalline sample during thermal agitation was found to depend on the ordering and disordering of molecules which in turn cause the lattice dipole to distort. A semiconducting behavior was detected for these systems as it was deduced from their conductance values (1.7 × 10−6 − 8.25 × 10−7 ohm−1 cm−1). The presence of substituents affects markedly the measured electrical conductivity and calculated activation energy values.

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Electrical conductivity and Seebeck voltage developed in -irradiated TiO2 was studied as a function of temperature. The conversion of n-type TiO2 into p-type observed after irradiation was explained on the basis of formation of inversion layer of p-type TiO2 due to the chemisorption of oxygen on the oxide surface during irradiation. Sign of the EMF of the electrochemical concentration cell of Ag/Ag+ with the addition of irradiated TiO2 was found to be exactly opposite to that due to the addition of nonirradiated oxide.

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