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-Tcure) 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 Tg, and to construct the iso-Tg 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.
The objective of our project was to develop an analytical method which can measure the VOCs (volatile organic compounds) to find the important microbial metabolites to predict the spoilage during storage of fruits. As a model system plums (Prunus salicina) inoculated with Penicillium expansum were chosen. Analyses were performed by solid-phase microextraction (SPME) coupled to gas chromatography (GC) — mass spectrometry (MS). The current study employs multivariate experimental design for the optimization of 4 factors, namely extraction time, desorption time, agitation and desorption temperature, by a 24-1 experimental design. Desorption time and agitation showed no significant effect on the amount of extracted concentration. For extraction time 25 min. and 250 °C for desorption temperature were chosen for the 2 important factors. Four kinds of samples (agar inoculated with P. expansum, plum inoculated with P. expansum, control plum and control agar) were measured for 4 days. Styrene, 1-methoxy-3-methylbenzene, methyl linoleate and a ‘non-identified aromatic compound’, were reported here as possible P. expansum marker compounds.
Winery wastewater treatment plants generally face severe nutrient deficiency, and therefore conventional technologies and supplementary nutrient dosing strategies may fail. The purpose of the paper is to show how traditional way of dosing N-source for marginal availability to nutrient deficient influents results in poorly settling activated sludge regardless of the application of aerated or non-aerated selectors. External N-source calculated for marginal availability resulted in nutrient deficiency due to the relatively high yield experienced (0.7 g biomass COD/g substrate COD). In the fully aerated system with overall N-deficiency, rapidly increasing overproduction of extracellular polysaccharide was experienced, leading to SVI (Sludge Volume Index) values up to 600 cm3 g−1. In the system with the non-aerated selector, initial nutrient deficiency could only be detected in the second reactor. Since neither overgrowth of floc-forming GAOs (Glycogen Accumulating Organisms) nor denitrification could be experienced, the non-aerated reactor operated as low-DO (Dissolved Oxygen) basin, attributing to the drastic overgrowth of filamentous bacteria leading to SVI values >1000 cm3 g−1. Since dosing external N-source for marginal availability is likely to cause severe biomass separability problems in activated sludge winery wastewater treatment, either pronounced N-overdosing and pre-denitrification or severe nutrient deficiency and GAO cultivation can rather be recommended.
Authors:T. Ljubka, Á. Lovas-Kiss, A. Takács, and A. Molnár V.
Epipactis albensis Nováková et Rydlo (Orchidaceae), a species previously undocumented in the flora of Ukraine, was found in three localities in this country (in vicinity of Chetfalva, Fanchykovo and Drotyntsi, Zakarpattia district) in 2012. The species (originally described from the Czech Republic) recently has only been known to exist in seven Central European countries. The three Ukrainian populations described here stretch within the floodplain of river Tisza. Based on measurements in 14 localities in Hungary, Ukraine and Romania the species has a considerably wide soil reaction tolerance (from 3.6 to 7.2 pHKCl). The fruit set of this strictly autogamous species is reasonably high (78%). The mean±SD thousand seed weight of the species was 0.0030±0.0005 grams, therefore E. albenis is classified into the hypermeichor seed-weight class. Recent discoveries of the species in Romania and Ukraine raise the possibility of its occurrence in further European countries.
Authors:A. Jobbágy, B. Kiss, V. Bakos, and G. Tardy
In order to decrease the organic load on the downstream domestic wastewater treatment plant, a three stage, fully aerated activated sludge system was established for the pretreatment of a vegetable processing wastewater. The results of the research verified that this design was inappropriate at the given, highly fluctuating wastewater quality. Nitrate formed through nitrification of the pea processing wastewater could not be denitrified, thus rising sludge occurred in the secondary clarifiers. On the other hand, during the corn campaign, severe deterioration of the COD (Chemical Oxygen Demand) removal efficiency, as well as the overproduction of extracellular polysaccharides leading to viscous bulking, were caused by the extremely high C/N ratio. In order to efficiently treat the wastewater of the vegetable processing industry, establishment of highly flexible systems with unaerated first stage proves to be necessary.
Authors:D. Polgári, B. Kalapos, V. Tisza, L. Kovács, B. Kerti, L. Heszky, and E. Kiss
The aim of this study was to characterize a gene associated with ripening in strawberry, a non-climacteric fruit. Differently expressed transcripts of candidate genes functioning in fruit development and ripening were identified from strawberry (
Duch.) in four ripening stages using the cDNA-AFLP method. The cDNA fragment designated C11M32M003 was selected from the putative ripening-related genes for further analysis. This transcript accumulated in the green receptacle, and the achene, but gene expression decreased in both tissues in parallel with the progress of ripening (Balogh, 2006).
analysis revealed that both the cDNA-AFLP fragment (C11M32M003) and the full-length cDNA AY695666 showed over 60% homology at the nucleotide level with two gene groups found in various plant species, including
. One of the candidate groups consisted of
sequences thought to be related to auxin biosynthesis. As an alternative, a lesser known gene group named
was suggested. The results of the detailed bioinformatic comparisons presented in this paper prove that the strawberry sequence analysed belongs to the
Authors:R.V Salamon, É. Vargáné-Visi, Cs.D. András, Zs. Csapóné Kiss, and J. Csapó
The addition of synthetic CLA is a possible way in order to compose foods enriched with conjugated linoleic acids (CLAs). The most environmental friendly methods for CLA synthesis are based on microbial biosynthesis. With homogeneous catalysis using organometallic catalysts (Ru and Rh complexes) high (approximately 80%) yields were obtained with high selectivity related to bioactive isomers. The heterogeneous catalysis has the advantage that at the end of the reaction there is no need for a supplementary separation operation or recycling of the catalyst. In heterogeneous process, the maximum yield may even be higher than 90% and the selectivity remains quite high as the reaction conditions are optimized. The substrates for obtaining CLAs are, in general, linoleic acid or alkyl linoleates and the catalysis is acidic. The yield and the selectivity depend on the strength and the type of acidic sites, as well as on the size distribution of the particles. Beside the existing catalytic methods, a photocatalytic process with UV and visible light irradiation with iodine promoter can be applied.
Authors:J. Kontschán, V. Kerezsi, B. Kiss, and M. Tóth
The hypopi of the species Sancassania chelone Oudemans, 1916 were collected from four pest beetle species, namely Melolontha melolontha (Linnaeus, 1758); Melolontha hippocastani Fabricius, 1801; Holochelus aequinoctialis (Herbst, 1790) and Tropinota hirta Poda, 1761. The infestation rate was the highest in H. aequinoctialis (80%), while it was 50%, 28% and 13% in M. hippocastani, M. melolontha and T. hirta, respectively. The majority of the mites were found on wings in case of the two Melolontha species, in contrary, the mites were present on the abdomen of the H. aequinoctialis and T. hirta. Melolontha hippocastani Fabricius, 1801; Holochelus aequinoctialis (Herbst, 1790) and Tropinota hirta (Poda, 1761) are new host species of S. chelone.