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Abstract  

The magnetic properties of poly(3-dodecyl-thiophene) (PDDT) irradiated by -beams have been studied by measuring the magnetic susceptibility and EPR spectra. The irradiated PDDT is characterized, similarly as the non-irradiated one, by an antiferromagnetic course of magnetic susceptibility with a Néel temperature of 237 K. It is suggested that the antiferromagnetic properties of PDDT are caused by transformation of polarons to bipolarons, which takes place at lower temperatures.

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Abstract  

The influence of -radiation on the d.c. conductivity of poly(3-hexadecylthiophene) (PHDT) doped with FeCl3 in chloroform, toluene, ethanol and nitrobenzene atmospheres has been studied. A different course of d.c. conductivity changes taking place in the atmosphere of solvent vapors (chloroform, toluene) and precipitants (ethanol, nitrobenzene) has been found. The character of changes can be influenced by polymer cross-linking initiated by -radiation.

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EU’s Common Agricultural Policy encourages maintaining agricultural production in less favored areas (LFA) to secure both stable production and income to farmers and to protect the environment. Recently the delimitation of LFAs is suggested to be carried out using common biophysical diagnostic criteria on low soil productivity and poor climate conditions all over Europe. The criterion system was elaborated by European Commission’s Joint Research Center (JRC) and its operational implementation comes under member state competence. This process requires the existence of an adequate national spatial soil information system with appropriate data structure and spatial resolution as well as a proper methodology for its analysis. Hungary possesses an appropriate, nationwide, 1:25,000 scale legacy dataset originating from the national soil mapping project, which was digitally processed and developed into the Digital Kreybig Soil Information System (DKSIS). In the paper we present how DKSIS was applied for the identification and delineation of areas in Hungary concerned by the common biophysical criteria related to soil. Soil data linked to soil profiles and SMUs were jointly spatially analyzed for the compilation of nationwide digital maps displaying spatial distribution of specific limiting factors.

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Analytical application of Cherenkov radiation

V. Protein content determination by Cherenkov photometry

Journal of Radioanalytical and Nuclear Chemistry
Authors:
F. Kulcsár
,
R. Novák
,
L. Szabó
, and
B. Matkovics

Abstract  

Data are reported on the development of a Cherenkov photometric producere, applying the basic principle of the method of LOWRY et al. At various amplifications and channel settings, linear correlations may be obtained between the logarithm of the protein content and the external standard activity or the channel ratio. The values obtained by Cherenkov spectrophotometry based on the Filin method display a linear correlation with each other with a good correlation coefficient.

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Abstract  

The influence of -radiation on the electric properties of Langmuir-Blodgett (LB) films of partially iodine-doped poly-(3-hexadecylthiophene) and stearic acid in interaction with selected environment-polluting gases has been studied. CO2, CO and NO2 increase the LB films conductivity and NO has a tendency to decrease the electric conductivity. The influence of -radiation was expressive onyl in the case of CO2, whereas NO2 brought about degradation of the conductive polymer.

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Abstract  

The diffusion of sulfur dioxide into partially iodine-doped poly (3-dodecylthiophene) and poly(hexadecylthiophene) has been studied. A direct dependence of the diffusion rate on the alkyl group lengths was ascertained. The diffusion rate could be increased by irradiation of the polymers.

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Abstract  

Formation of oxidizing and reducing radicals has been studied by pulse radiolysis of [Fe(CN)6]4––BrO 3 –CN system in ethylene glycol — water solvent mixture. Oxidizing ·BrO2 and BrO radicals formed by electron scavenging with ·BrO 3 were identified and their reactions were investigated. The reaction of hydroxyl radicals with ethylene glycol leads to formation of reactive radicals with reducing properties and of compounds which reduce slowly in dark the ferricyanide formed in the reaction of ·BrO2 radical with ferrocyanide.

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Abstract  

The influence of certain gases on the properties of thermally treated and -irradiated Langmuir-Blodgett (LB) films of poly (3-hexadecylthiophene) and stearic acid has been studied. Both the heat and -radiation brought about some structural surface layer changes, leading to temporal variations of the course of the in-plane conductivity of films affected by the presence of applied gases.

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Related to ongoing (re)forestation in the Great Hungarian Plain the short-term influence of changing land cover was studied on the grains of skeletal sandy soils. In three sampling areas with forest and grassy/arable control plots, the 0.1–0.2 mm grain size fraction of samples taken every 20 cm from the 0–100 cm sandy soil layer (totalling 22,509 grains) were separated and described with optical mineralogical microscope. In order to distinguish sand grains of forest-covered and control areas (grassland/arable land), the results of mineralogical and morphological observations were compared. It was revealed that the amount of feldspar grains is 8–9 times less than the amount of the quartz ones. The increase in the quartz/feldspar (q/fp) ratio is tied to the “consumption” of feldspars: the intense consumption of potassium by trees. Under the forest-covered fields, the number of in-situ crushed grains increased. Grains with etch pits are frequent in samples from the grasslands (except in Hajdúsámson). In samples of forest-covered areas a greatly increased number of brown grains with limonite and/or humus films were observed. The gained results can be useful in proving earlier land use in forested fields.

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Abstract  

The purpose of this study was to further characterize the altered metabolism spondylolisthesis that promotes disease progression. Degenerative human cartilage (intervertebral disc, facet joint and vertebral end-plate) was obtained during 15 posterior lumbar spine interbody fusion procedures performed at the University of Szeged. The thermal properties of samples were determined by differential scanning calorimetry (Mettler-Toledo DSC 821e). Greatest change in the enthalpy was observed in the intervertebral disc samples: −1600.78 J g−1. Denaturation caused by heating in the normal human hyaline cartilage needed −1493.31 J g−1 energy. Characterization of the altered metabolism that promotes disease progression should lead to future treatment options.

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