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Gy Bárdossy and J Fodor: Evaluation of Uncertainties and Risks in Geology. Springer-Verlag, 2004

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Abstract  

The kinetics of radiation initiated polymerization of HDDA and HDDMA were investigated in cyclohexane solutions by pulse radiolysis with transient spectroscopic detection. The maxima of the transient absorption spectra observed below 300 nm were shifted to longer wavelength with increasing the monomer concentration indicating a change in the structure of the intermediates. In HDDA solution of 10 mmol·dm−3 concentration a second peak appears at ∼330 nm as a consequence of the onset of oligomer radical formation. In HDDMA solution oligomer formation can be detected at higher concentration because of the lower reactivity of this monomer. The rate constants of termination (2k t) were determined at different monomer concentrations.

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The use of vertical electric dipole transmitter and receiver turns out to be advantageous in the exploration of lateral inhomogeneities of high resistivity layers by transillumination measurement. Geological information can be made clearer by transformation of the amplitude response to apparent resistivity spectrum. The apparent resistivity calculated by the geometric factor in the quasistationary frequency range depends decisively on the galvanic effect of the high resistivity layer containing the electrodes. In the so called frequency dependent inductive apparent resistivity deduced based on the amplitude response of the uniform half — respectively full — space at low frequencies mainly the effect of the shoulder formation, at frequencies high enough the effect of the resistive layer containing the electrode will dominate. The knowledge of these apparent resistivities on the one hand helps the determination of the effective resistivity, which is independent of the ray-length and indicates the continuity or discontinuity of the resistive layer along the equatorial plane. On the other hand in the case of transilluminations with areal coverage they can be used in the selection of the horizontal-layered, uniform start model, needed in the reconstruction of the spatial distribution of the resistivity-variation. Reconstructions of measured and simulated data demonstrate the applicability of the procedure.

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Possibilities of detection of abrupt lateral conductivity changes are presented by mapping of the surface vertical magnetic field in the vicinity of the borehole. Magnetic field components generated by vertical electric bipole do not exist over a uniform or horizontally layered earth. Vertical magnetic field is caused exclusively by resistivity inhomogeneities. Therefore it is very sensitive to lateral discontinuities. A simplified inversion procedure — searching the anomalous subsurface horizontal current distribution linked with the discontinuity — is discussed and tested on synthetic examples.

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Numerical studies indicate that information can be gained about the layering even in the transition zone of the source, down to a considerable depth with a properly planned frequency sounding measuring system. As it has been demonstrated, the high resistivity basement can be revealed even with a source-receiver separation 2-times larger than its depth.Model studies demonstrate that the transformation of the measured field into the so-called effective resistivity — with the use of a set of homogeneous earth responses calculated for several different resistivity values — offers a useful tool in the controlled electric bipole source measurement. Effective resistivity frequency sounding curves in the transition zone also give information about layering, and make additional transformations useful in preliminary interpretation.Effective resistivity sounding curves of arbitrary configuration can be determined from any individual field amplitude and phase, or from quantities derived from them. Therefore they can be applied for single — either electric or magnetic — field component frequency sounding as well.

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Apple is one of the most important fruit grown and consumed in the temperate climate region. About 2% of the European population suffers from several allergenic reactions after consumption. Presence of 7 members of Mal d 1 gene family occurring in some apples was examined by PCR. The Mal d 1.01 and 1.02 genes could be detected from 91% and 79% of apple cultivars, respectively, due to the high degree of conservative regions. The Mal d 1.04 gene has 4 functional varieties and 2 pseudo-alleles, so it is highly variable. The PCR amplifi cation with Mal d 1.06 primers gave one or two fragments with different sizes. The electrophoretic pattern is a suitable means to select apple cultivars according to their low, medium, or high Mal d 1 allergen content. Florina apple showed the single 154 bp allele, which is responsible for the small Mal d 1 allergen content in homozygote form..

Several samples gave weak signal or did not give any fragment-band on the gel, so Mal d 1.07 and 1.08 genes might have more varieties. Regarding the Mal d 1.09 gene we have found that it has conservative sequences in different apple cultivars and does not have too many varieties.

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Yellow pea flour contains very low quantity of prolamins, thus it could be a good alternative dietary source for individuals suffering from celiac disease or wheat allergy. Beside emulsifiers, enzymes can be used for developing noodle structure with high quality. Transglutaminase (TG) enzyme was tested in model systems for improving noodle structure by using beneficial cross-linking property of the enzyme. Sensory-and cooking properties and biochemical attributes of proteins were evaluated to characterize structure-function relationships in accordance with the concentration of the applied enzyme. The amount of water and salt soluble protein fractions was reduced meaningfully and the molecular weight distributions assessed by SDS PAGE were changed by addition of 50–200 mg kg −1 TG enzyme. At the same time, sensory properties were improved and high water uptake and low cooking loss were also observed. Forasmuch an increase has been expected in the amount of the cross-linked molecules, the cross-reactivity of prolamins with anti-gliadin antibody was also tested to reduce the risk related to gluten sensitivity. Finally, the possible contamination with wheat was controlled by DNA-based PCR.

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Abstract  

The reactions of hydroxyl radical and hydrated electron intermediates of water radiolysis were studied in the radiolytic degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) at pH values of 4, 6 and 8. The hydrated electron reactions are also suggested to contribute to the aromatic ring decomposition in addition to the highly effective hydroxyl radical reactions. The experimental results suggest also some contribution from the O2 −•/HO2 pair to the degradation. The degradation efficiency was found to be the highest at pH 8 and the lowest at pH 6.

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Current density pseudosections derived by filtering and probability tomography from calculated VLF vertical magnetic profiles over synthetic 2D targets with geometrical shape are examined critically. It was found that the position and shape of  target only in the case of single inhomogeneities with very limited cross-sectional area and simple shape can be revealed reliably by them. The locations of sharp cross-sectional boundaries can only be guessed. Fictitious, misleading current-density indications occur in the case of laterally extended, or multiple targets at too wide filter windows. Both procedures suppose that the measured values originate in the superposition of the magnetic fields of individual stationary current-lines inside the target. It is shown that in the quasistationary range the shape and position of the target can be outlined sharply using this simplified form of the forward problem solution and performing an inversion with respect of the vertices of the polygon approximating the cross-sectional contour of the target. Several kinds of inversionprocedures  were tested.

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Successful applications of toxins derived from Bacillus thuringiensis (Bt) strains in Bt-based bioinsecticides and more recently in Bt-plants in crop protection have enhanced the importance of analytical quantification of Cry toxin dosages for studies on various topics including environmental risk assessment (ERA), resistance management, quality control and regulatory compliance. It is essential to follow-up distribution and environmental degradation of these lectin type, crystalline (Cry) toxin proteins showing insect specificity at order level. Thus, Cry1Ab toxin produced by Bt-maize of genetic event MON 810 is specific to lepidopteran species. Widely used analytical methods for detection of Cry toxins are enzyme-linked immunosorbent assay (ELISA) systems. Reported Cry1Ab toxin concentrations in MON 810 maize show high variability: order of magnitude differences have been observed among various plant parts from different varieties, cultivated at different locations, and sometimes even within the same plant variety at a single location. Besides biological sources of variability, numerous analytical problems have been identified and are reported in this report, influencing the results of quantitative determination of Cry1Ab toxin and explaining the high variability among documented data on toxin content. Conclusions in every case refer to genetic event MON 810, but can be extended to other genetic events producing Cry1Ab toxin.

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