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Abstract  

The possibility of quantitative boron determination via (n,α) reaction in silicon and B2O3+PVA samples has been studied. As alpha-sensitive track detector Makrofol-E polycarbonate foil and as neutron source lmg252Cf with a cadmium ratio of 8 were applied. It was shown that, if the lowest acceptable track density was 103 tracks cm−2 the method could be used to measure B concentrations down to 1 ppm.

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Changes of edible oil quality factors and formation of 3-monochloro-1,2-propanediol fatty acid esters (3-MCPD-FE) during deep-fat frying in four different experiments (control, salt, pork chop, and chicken liver) with high oleic sunflower oil were compared in this study. Based on the results of investigated oil quality parameters, which were free fatty acid (FFA), anisidine value (AV), UV extinction at 232 and 268 nm (E232 and E268, respectively), and total polar material (TPM), only a modest deterioration of the frying oil was observed. As we expected, the 3-MCPD-FE content in the control samples did not reach the limit of quantification (0.1 mg kg–1), while the table salt itself caused a slight increase. The results of pork chop and chicken liver experiments were not statistically different from each other, after the third frying circle 0.52 and 0.39 mg kg–1 3-MCPD-FE levels were reached, respectively. Based on these values, the human exposure estimation resulted in a low risk.

Open access
Nanopages
Authors:
I. Szendrő
,
K. Erdélyi
,
Zs. Puskás
,
M. Fábián
,
N. Adányi
, and
K. Somogyi

Due to the changes of the refractive indices, the planar optical waveguides are sensitive to the surrounding media, to the adsorbates, etc. on their surface. The sensitivity of such a waveguide layer can be enhanced when its thickness is lowered down to the nanometer range. Such sensors can be successfully operated both in inorganic chemistry and in life sciences as label free biosensors. Principles and some results are demonstrated. Further on, application of transparent conductive oxides for voltammetric measurements in combination with the classical waveguide sensor will be demonstrated. Development and results of a combined system is described and first results with simultaneous measurements are demonstrated. An indium tin oxide nanolayer is deposited and activated on the top of the sensor chip. This electrically conductive oxide layer serves as working electrode in the specially developed electrochemical cuvette. In this work results are presented for simultaneous use of these two methods and for simultaneous measurement of refractive index changes of the waveguiding system and that of electrical current changes. The first basic results are demonstrated using H2O2 and dye solutions, using KCl and TRIS as buffer and transport media.

Open access
Acta Alimentaria
Authors:
M. Mardani
,
L. Somogyi
,
I. Szedljak
,
I. Prauda
,
J. Farmani
, and
K. Badakné Kerti

Abstract

Sea buckthorn (Hippophae rhamnoides) with high antioxidant capacity is distributed all over the world, but has never been used as a natural antioxidant in oils to replace synthetic antioxidants. Therefore, this study was performed to investigate the effectiveness of sea buckthorn extract in comparison to a common natural antioxidant rosemary extract and a synthetic antioxidant on retarding lipid oxidation. First the extracts were characterised, and it was found that sea buckthorn extract had higher polyphenol contents, radical scavenging activity, and higher antioxidant capacity. Then the proper concentrations for the use of these antioxidants were determined. Additionally, the progress of lipid oxidation during cycles of frying was assessed in terms of free fatty acids content, peroxide value, p-anisidine value, TOTOX value, colour, total polar compounds, and Induction period. The general order of effectiveness for inhibition of high oleic sunflower oil degradation during frying was: sea buckthorn > BHT > rosemary > control (P <0.05).

Open access

Women with gestational diabetes mellitus (GDM) are at high risk of subsequently developing type 2 diabetes mellitus which is an important cardiovascular risk factor. We have evaluated whether preclinical morphological and functional arterial changes are present in GDM. Diameter, intima-media thickness (IMT), intima-media cross-section area (IMCSA) and elasticity features (compliance, distensibility coefficient, circumferential strain, stiffness index (SI) α and β, incremental elastic modulus) of the common carotid arteries (CCA) were studied in the 3rd trimester in 25 women with GDM, and 17 normal pregnant women matched for age and body mass index using an ultrasonographic vessel wall-movement tracking system and applanation tonometry. Mean IMT, IMCSA and SI α tended to be larger, whereas compliance was smaller in women with GDM but none of these differences were significant. Serum glucose (4.99±0.51 vs. 4.79±0.61 mmol/L, p=0.37) and HbA1c (5.33±0.27 vs. 5.36±0.47 mmol/L, p=0.85) proved normoglycemia in both groups. In conclusion, by the combination of methods we applied in this case control study, neither morphological nor functional characteristics of large elastic arteries differ significantly between well-treated normoglycemic women with GDM and non-diabetic pregnant women in the 3rd trimester.

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