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  • Author or Editor: M. Takács x
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The aim of the present paper is to give an overview on the issue of the archaeological investigations of the chronology of medieval settlements in Hungary. After a brief introduction dealing with theoretical and/or methodological questions, a description of the literature is given in order to explain a rather chaotical picture of a graphic image of settlement dating (Fig. 1) . In the last chapter of the paper one can find an attempt to give a schema for a frame-like — i. e. not exact — dating of medieval settlements in Hungary (Fig. 2) .

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The Hot Water Percolation (HWP) technique for preparing soil extracts has several advantages: it is easily carried out, fast, and several parameters can be measured from the same solution. The object of this study was to examine the possible use of HWP extracts for the characterization of soil organic matter. The HPLC-SEC chromatograms, UV-VIS and fluorescence properties of the HWP extracts were studied and the results were compared with those of the International Humic Substances Society (IHSS) Soil Humic Acid (HA), IHSS Soil Fulvic Acid (FA) and IHSS Suwannee Natural Organic Matter (NOM) standards as well as their HA counterparts isolated by traditional extraction methods from the original soil samples. The DOM of the HWP solution is probably a mixture of organic materials, which have some characteristics similar to the Soil FA fractions and NOM. The HWP extracted organic material can be studied and characterized using simple techniques, like UV-VIS and fluorescence spectroscopy.

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The content of potentially antioxidant, anticarcinogenic and antiallergic flavonoid aglycons, quercetin, kaempferol, myricetin, apigenin and luteolin of 45 fruits were determined by RP-HPLC with UV detection. Fresh and dried fruits were purchased in the local markets in Budapest at a period of their most frequent consumption. Total flavonoid content of fruits varied between 0–1000 mg kg –1, the average concentration was about 30 mg kg –1 fresh weight. Quercetin could be detected in most fruits, namely in apples, pear, plums, sweet and sour cherry and berries between 10–53 mg kg –1. Luteolin at a concentration of 20 mg kg –1 was found in melons, apples, kiwi and lemon. Myricetin was in detectable amount in redcurrant, and at very high concentration in some berry fruits (mulberry 453 mg kg –1, raspberry 540 mg kg –1, blackberry 636 mg kg –1, strawberry 994 mg kg –1), and in walnut (4565 mg kg –1). Kaempferol and apigenin were not found in the fruits investigated. None of the five flavonoids was found in some variety of grapes, in peach, pear, banana, orange, grapefruit and tangerine, in nuts such as almond, pistachio, nuts, and in dried fruits such as raisin, date, fig and prunes. These data provide a basis for the evaluation of the average daily intake of Hungarian population and for an epidemiological evaluation of health-promoting effects of flavonoids. __

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Investigation of lipid peroxidation as a method of quality control in the food industry requires a simple, fast and reproducible method. The preliminary results about an intensive test are presented. Interaction of oil samples and air is intensified by using a piece of filter paper fitting exactly into the bottom of a laboratory vessel as a support. At elevated temperatures (50–55 °C) generated by infrared light the rate of lipid peroxidation is much increased. The test can be carried out in a one-pot-system. The use of this intensive test is advantageous in studying of the effect of metal salts on lipid peroxidation. It is suggested that this intensive test can be made suitable for the study of different effects and for screening chemical agents, especially that of new antioxidants.

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Nitrate accumulation in plants is a natural phenomenon resulting from uptake of nitrate ion in excess of its reduction and subsequent assimilation. The water soluble nitrate content of various carrot and red beet varieties was measured as a function of irrigation and mineral supplement in three years. In the first year, the nitrate content increased in both roots (significant differences were found for three carrot and at three red beet cultivars) following the irrigation. The activity of nitrate-reductase in the leaves was also significantly higher after irrigation in three red beet varieties in 1998. The mineral supplement in most of the carrot varieties increased the nitrate content. In the third year, the impact of water supply showed various tendencies in nitrate accumulation in both vegetables. On the basis of results for three years, the conclusion was that the seasonal and varietal differences were also remarkable.

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Cereal Research Communications
Authors: J. Horvát, G. Kazinczi, A. Takács, M. Torma and A. Kovács
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Abstract  

The use of the 99Mo 99mTc generator in nuclear medicine is well established world wide. The production of the 99Mo (T1/2 = 66 h) parent as a fission product of 235U is largely based on the use of reactor technology. From the early 1990's accelerator based production methods to provide either direct produced 99mTc or the parent 99Mo, were studied and suggested as potential alternatives to the reactor based production of 99Mo. A possible pathway for the charged particle production of 99mTc and 99Mo is irradiation of molybdenum metal with protons via the reaction 100Mo(p,2n)99mTc and 100Mo(p,pn)99Mo, respectively. The earlier published excitation functions show large differences in their maximum that result in large differences in the calculated yields. We therefore decided to study the excitation function for these proton-induced reactions. In this work the newly measured excitation functions as well as an evaluation of earlier measured data and a discussion of the observed disagreements are presented.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: F. Ditrói, F. Tárkányi, S. Takács, M. Uddin, M. Hagiwara, M. Baba, A. Ignatyuk and S. Kovalev

Abstract  

Activation data of lead are of great importance due to the widespread applications of this element in various technological fields and to the well known adverse effects to biological systems. Use of high sensitivity radioanalytical techniques allows study of uptake, distribution and speciation. Cross sections of deuteron induced nuclear reactions on lead were measured up to 40 MeV using the standard stacked foil irradiation technique and high resolution gamma-ray spectrometry. Experimental cross sections and derived integral yields are reported for the natPb(d,xn)203,204,205,206,207Bi, natPb(d,x)203Pb202Tl reactions. Only one set of experimental cross section data was found in the literature. The experimental data are analyzed and compared with the results of the theoretical model code ALICE-IPPE and with the experimental integral yield reported in the literature.

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Tomato spotted wild virus (TSWV) has become an important plant pathogen during the past 10 years in Hungary. This virus belongs to the family of Bunyaviridae, genus Tospovirus. According to the latest studies, this virus has about 1090 host plant species, including crops and weeds. In the autumn of 2009, some Aristolochia clematitis plants were collected showing symptoms of TSWV infection. On the basis of electron microscopic and molecular studies, leaf samples of Aristolochia clematitis L. found in a vineyard proved to be infected with Tomato spotted wilt virus (TSWV). This is the first report on the occurrence of TSWV in Aristolochia in Hungary.

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