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Abstract  

It is shown that if there exists a binary code C of length d and covering radius k then a zonotope in the d-dimensional Euclidean space can be illuminated by C affine subspaces of dimension k. Applying results from coding theory, the exact value of the illumination numbers of d-dimensional parallelotopes is determined in some special cases.

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Abstract  

The curing of a thermoreactive alkyd-melamine-formaldehyde resin system was investigated by rheologycal, TG and TMA-analysis, in order to construct the time-temperature-transformation diagram. The points of the gelation curve were determined by measuring the increase in viscosity during isothermal curing at different temperatures. A power-function could be fitted to the gelation curve, which is suitable to estimate gelation at any curing conditions, as well as to establish storage conditions. The reaction in the resin matrix was followed by monitoring the loss of mass during isothermal curing at different temperatures. The final section of the resulted iso-curing temperature (iso-T cure) diagrams could be fitted with logarithmic functions, which may be used for estimating the conditions needed to a given, desirable mass loss, i.e. conversion. The steepness of the curves increases with temperature suggesting the forthcoming of degradation during cure with increasing temperature. From these data the iso-mass loss curves of the TTT-diagram were constructed. For determining the iso-Tg curves of the TTT-diagram isothermal curing was carried out in a drying oven at different temperatures, followed by TMA measurements. The iso-Tcure diagrams served to determine T g , and to construct the iso-T g curves of the TTT diagram. Vitrification curve is far beyond conditions of storage, curing and degradation, meaning that the resin matrix is in rubbery physical state before, during and after the cure. Curing conditions resulting degradation can also be estimated from the TTT-diagram.

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Abstract  

A new preconditioned conjugate gradient (PCG)-based domain decomposition method is given for the solution of linear equations arising in the finite element method applied to the elliptic Neumann problem. The novelty of the proposed method is in the recommended preconditioner which is constructed by using cyclic matrix. The resulting preconditioned algorithms are well suited to parallel computation.

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The biologically active amines of grapes, aszú-grapes, aszú-wines of Tokaj region were analysed to study the effect of Botrytis cinerea on the grapes. It was established that grapes contained mainly spermidine, putrescine and spermine, however, in the aszú-grapes new amine compounds such as agmatine, phenethylamine, butylamine and pentylamine isomers appeared. The spermine content showed an increase in all aszú-grape varieties compared to the grapes. During winemaking processes, spermine disappeared and the concentration of tyramine increased in the aszú-wines. The concentration of spermidine decreased during the ageing of the product. The ratio of tyramine and amine content of the samples were found to be within a limited interval.

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Acta Mathematica Hungarica
Authors: Gy. Kiss, A. Malnič, and D. Marušič
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Calorimetric test of purity II

Comparison of dynamic and stepwise measuring technique, optimization of data-processing

Journal of Thermal Analysis and Calorimetry
Authors: Gy. Kiss, K. Seybold, and T. Meisel
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Calorimetric test of purity I

Analysis of descriptions of the melting curve dH/dT vs. T

Journal of Thermal Analysis and Calorimetry
Authors: Gy. Kiss, K. Seybold, and T. Meisel
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Acta Botanica Hungarica
Authors: Á. K. Kiss, L. Gy. Szabó, and K. Szabó

Komárek, J. and Anagnostidis, K. (2005): Cyanoprokaryota. 2. Teil: Oscillatoriales. - In: Büdel, B., Krienitz, L., Gärtner, G. and Schagerl, M. (eds): Süßwasserflora von Mitteleuropa, Band 19/2. Spektrum Akademischer Verlag, Elsevier GmbH, München, 759 pp.; Ross, I. A. (2005): Medicinal plants of the world - chemical constituents, traditional and modern medicinal uses. Volume 3. - Humana Press, Totowa, New Jersey, 623 pp. (ISBN 1-59259-887-0); Siver, P. A., Hamilton, P. B., Stachura-Suchoples, K. and Kociolek, J. P. (2005): Diatoms of North America: The freshwater flora of Cape Cod, Massachusetts, U.S.A. - In: Lange-Bertalot, H. (ed.): Iconographia Diatomologica. Annotated Diatom Micrographs. Vol. 14. A. R. G. Gantner Verlag K. G. Ruggel, 463 pp.;

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Consumption of dietary supplements (DS) has been showing a persistent, rapidly growing tendency all over the world. A new branch has been created on the borderline of food and pharmaceutical industries. It is a general tendency that the policy and regulation towards the products of this branch are lagging far behind the practice. This is an especially important problem with adolescents. To work out an efficient regulatory framework, we have to have an adequate picture on consumer behaviour and attitudes towards these products. Based on literature analysis of two focus group interviews, we have developed a motivational model on usage of DS, which has been tasted during a direct-question survey involving more than 500 respondents. Our results have proven that the consumption of DS is proliferated among young recreational athletes. One quarter of them consumes proteins, one tenth L-carnitine at least 2–3 times a week. The most important motivational factor is the improvement of sport performance. The level of confidence in these products is considerably influenced by peers and trainers. The propensity to underestimate the potentially adverse consequences of these products is high.

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Summary  

Thirty-seven episodes of dust intrusion were observed between February 12, 1991 and August 31, 2000 in the Hungarian atmosphere and found to be of Saharan origin. They have been assigned to typical source areas in Northern Africa selected by systematic investigations related to the Mediterranean Basin. Elemental concentrations and regional signatures deduced from PIXE analysis, total suspended particle mass, and black carbon mass have been measured on dust samples collected in Debrecen, Hungary. These data combined with Aerosol Index data, and dust plume axes obtained from TOMS data from NASA satellites were used for assigning the most probable source areas of the dust transported to the sampling site. Our data and conclusions are in accordance with other published investigations on the predominant role of Saharan dust emission in building up the aerosol load of the global atmosphere.

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