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The article presents a theoretical analysis of electromagnetic compatibility (EMC) and experimental measurement of effects of radiation and acoustic emission of high-voltage transformers for electronic equipment and working personnel in a control room. Electromagnetic compatibility and safety of equipment are not considered as two distinct areas of study in electric and electronic safety. Economic criteria cannot compromise safety but at the same time immunity levels must be relevant in order to establish a “Functional Safety”. Introducing Special Immunity Levels in the level of equipment testing allows us to combine the two areas of EMC and safety. The measurement was carried out in high-current of very high-voltage distribution station. A real-life analysis of effects of electric and electromagnetic field was carried out. FFT was used for mathematical processing of data which were later presented in a graphical form of a spectrally analyzed area. In the last part of the paper we discuss the suitability of acoustic camera to perform contactless monitoring of the health and operation conditions of the power transformer by analyzing acoustic field generated by the transformer core and windings in near control room.

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Contamination by microscopic fungi and mycotoxins in different bee pollen samples, which were stored under three different ways of storing as freezing, drying and UV radiation, was investigated. During spring 2009, 45 samples of bee-collected pollen were gathered from beekeepers who placed their bee colonies on monocultures of sunflower, rape and poppy fields within their flying distance. Bee pollen was collected from bees' legs by special devices placed at the entrance to hives. Samples were examined for the concentration and identification of microscopic fungi able to grow on Malt and Czapek-Dox agar and mycotoxins content [deoxynivalenol (DON), T-2 toxin (T-2), zearalenone (ZON) and total aflatoxins (AFL), fumonisins (FUM), ochratoxins (OTA)] by direct competitive enzyme-linked immunosorbent assays (ELISA). The total number of microscopic fungi in this study ranged from 2.98 ± 0.02 in frozen sunflower bee pollen to 4.06 ± 0.10 log cfu.g(-1) in sunflower bee pollen after UV radiation. In this study, 449 isolates belonging to 21 fungal species representing 9 genera were found in 45 samples of bee pollen. The total isolates were detected in frozen poppy pollen 29, rape pollen 40, sunflower pollen 80, in dried poppy pollen 12, rape pollen 36, sunflower 78, in poppy pollen after UV radiation treatment 54, rape 59 and sunflower 58. The most frequent isolates of microscopic fungi found in bee pollen samples of all prevalent species were Mucor mucedo (49 isolates), Alternaria alternata (40 isolates), Mucor hiemalis (40 isolates), Aspergillus fumigatus (33 isolates) and Cladosporium cladosporioides (31 isolates). The most frequently found isolates were detected in sunflower bee pollen frozen (80 isolates) and the lowest number of isolates was observed in poppy bee pollen dried (12 isolates). The most prevalent mycotoxin of poppy bee pollen was ZON (361.55 ± 0.26 μg.kg(-1)), in rape bee pollen T-2 toxin (265.40 ± 0.18 μg.kg(-1)) and in sunflower bee pollen T-2 toxin (364.72 ± 0.13 μg.kg(-1)) in all cases in frozen samples.

Contamination by microscopic fungi and mycotoxins in high moisture corn (HMC) silages conserved by chemical additives was investigated. The samples were examined for the concentration and identification of microscopic fungi able to grow on Malt and Czapek-Dox agar and for mycotoxins content (deoxynivalenol, T-2 toxin, zearalenone and total aflatoxins, fumonisins, ochratoxins) by direct competitive enzyme-linked immunosorbent assays. The average fungal counts were 3.37 +- 2.52 log cfu/g in control HMC silages, 2.91 +- 0.51 log cfu/g in HMC silages treated by organic salts and inorganic salt, 3.62 +- 1.46 log cfu/g in HMC ensiled with organic acids and 3.49 +- 1.12 log cfu/g of HMC silages treated by organic acids along with organic salt. In this study, 740 isolates belonging to 10 fungal species representing 9 genera were recovered. The genera of microscopic fungi most frequently found in HMC were Penicillium (56.49 percentages) and Paecilomyces (32.16 percentages). T-2 toxin was the secondary metabolite with the highest concentration ranging from 179.13 +- 3.04 to 249.40 +- 24.69 micrograms/kg, followed by deoxynivalenol and total fumonisins. The highest mean of deoxynivalenol level was 0.13 +- 0.02 mg/kg and concentration of total fumonisins ranged from 20.13 +- 2.53 to 90.33 +- 10.35 micrograms/kg. This study indicated that application of chemical additives containing organic acids, organic salts and inorganic salt was sufficient to inhibit mycotoxins formation. The use of calcium formiate, sodium benzoate and sodium nitrite resulted in high hygienic quality of HMC silages and significantly reduced the concentration of zearalenone, deoxynivalenol and total ochratoxins and fumonisins.