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Abstract  

57Co Mössbauer emission spectra of undoped and Fe or Mg melt-doped LiNbO3 single crystals show substantial amounts of the nucleogenic Fe3+ charge state (*Fe3+) which was generated as an after-effect of the electron-capture of 57Co2+. The proportion of *Fe3+ is markedly dependent on the Mg content and on the stoichiometry of the sample. Electron trapping is described within the model of competing acceptors. The capabilities of the model are investigated in defect structure analysis and charge trapping studies of LiNbO3.

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Acta Alimentaria
Authors:
R. Tömösközi-Farkas
,
Zs. Polgár
,
M. Nagy-Gasztonyi
,
V. Horváth
,
T. Renkecz
,
K. Simon
,
F. Boross
,
Z. Fabulya
, and
H. Daood

Anti-nutritive components in multi resistant potato cultivars were investigated in relation to conventional and organic farming for three years. Glycoalkaloids, nitrate, nitrite, asparagine, and glutamine contents of tubers were examined. Farming technology was found not to have an effect on the level of glycoalkaloids, which was influenced mostly by the genotype and season. Nitrogen fertilisation caused significant increase in nitrate, asparagine, and glutamine contents as compared to organic farming. Nitrite content was found to be more independent of farming technologies than nitrate. Tubers of cultivar Rioja had the lowest nitrate content irrespective of season or technology. In conclusion, the absolute amount and changes of different anti-nutritive components of potato tubers were influenced differently by the technology, genotype, and season in a complex manner. Organic farming had no effect on the glycoalkaloid content, but the nitrate levels had a tendency to be lower compared to conventional farming. This can be seen as a positive effect of organic farming.

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Acta Botanica Hungarica
Authors:
F. Horváth
,
Zs. Molnár
,
J. Bölöni
,
Zs. Pataki
,
L. Polgár
,
A. Révész
,
K. Oláh
,
D. Krasser
, and
E. Illyés

The survey results of the MÉTA program are managed with centralised relational database management system (MS SQL 2000) developed and set up in a local area network. Besides the MÉTA database server, a publishing server, an archiving server and a GIS workstation were applied. The core information entities of the MÉTA database are: information subproject, MÉTA quadrate, MÉTA hexagon, (semi-)natural habitat, potential vegetation with numerous habitats, landscape ecology and land use attributes, and surveyor. This information is coded in the nine main tables of the normalised database. In the recent state there are almost 1,500,000 records in the main tables that are managed in 241 independent fields. The published version of the MÉTA database supports the query service, and handles this information in 7 denormalised main tables. This much more redundant version is 11 GB in size. The 20.6% (179 man-month) of the human resources in the MÉTA program were devoted to the information tasks (set up and preparation, MÉTA database and information system development, replenishment and quality assessment, MÉTA query, GIS and printing services) between 2002 and 2007. The basic structure of the MÉTA database version 1.2 is finalised and the main functions regarding data processing have been developed. The accomplishment is higher than 90%, quality assessment is under way, while scientific verification and data harmonisation are started. The area of (semi-)natural and degraded vegetation of Hungary is estimated to 1,800,000 hectares (19.4% of the country) of which the natural, semi-natural is about 1,200,000 hectares (12.9% of the country). All of these are highly fragmented and unevenly distributed over the country. It is shown by several basic figures, professional content and quality measure facts of the database. There is also a fact sheet of surveyors that shapes the important characters of their field experience profile, too.

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