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Piotr Oramus, Tomasz Chmielewski, Tomasz Kuczek, Wojciech Piasecki and Marcin Szewczyk

Abstract

Electric arc is a complex phenomenon occurring during the current interruption process in the power system. Therefore performing digital simulations is often necessary to analyse transient conditions in power system during switching operations. This paper deals with the electric arc modelling and its implementation in simulation software for transient analyses during switching conditions in power system. Cassie, Cassie-Mayr as well as Schwarz-Avdonin equations describing the behaviour of the electric arc during the current interruption process have been implemented in EMTP-ATP simulation software and presented in this paper. The models developed have been used for transient simulations to analyse impact of the particular model and its parameters on Transient Recovery Voltage in different switching scenarios: during shunt reactor switching-off as well as during capacitor bank current switching-off. The selected simulation cases represent typical practical scenarios for inductive and capacitive currents breaking, respectively.

Open access

Tomasz Knapowski, Wojciech Kozera, Elżbieta Wszelaczyńska, Jarosław Pobereżny, Joanna Cieślewicz and Jarosław Chmielewski

Abstract

The aim of the study was to determine the effect of application of small amounts of nitrogen to the soil together with foliar application of micronutrients on the content of copper, manganese and zinc in the grain of spelt (Triticum aestivum ssp. spelta L.). The study was based on a two-factor field experiment conducted in 2009–2011 on very good rye complex soil. Nitrogen was applied in the form of ammonium nitrate (34% N), and manganese and copper were applied to the leaves in the form of the fertilisers Adob Mn (1.5 l∙ha−1) and Adob Cu (1.0 l∙ha−1), respectively. The results indicated that the nitrogen fertilisation, the foliar application of micronutrients and the interaction of these factors significantly determined the contents of copper, manganese and zinc in the grain. The highest content of Cu and Mn in the material was obtained following the application of 50 kg N·ha−1, and an increase in nitrogen application (to 50 kg·ha−1) caused a decrease in the content of zinc in the grain. Foliar application of Cu, Mn and both elements together resulted in significant changes in the concentrations of Cu, Mn and Zn in the plant material as compared to treatment without the application of micronutrients. The mineral fertilisers at the rates applied had a beneficial effect on the chemical composition of the grain, and thus on its quality, and this was achieved with substantially lower consumption of agrochemicals than that in the case of agrotechnical procedures for traditional cereals. It can, therefore, be concluded that this practice is environment friendly and can significantly reduce the negative impact of agricultural activity.

Open access

Elżbieta Wszelaczyńska, Jarosław Pobereżny, Katarzyna Gościnna, Jarosław Chmielewski, Tomasz Knapowski, Wojciech Kozera and Edward Majcherczak

Abstract

The aim of the research was to define changes in the content of NO3¯ determined by the environment and processing in products from five cultivars of carrot, orange in colour. Besides this, in the research, the human intake of toxic compounds found in processed foods was also assayed. All the processed foods were produced at laboratory scale compliant with the applicable guidelines and norms. The content of nitrates in processed foods depended significantly on the genetic conditions of material and on the processing method. Of all the cultivars under study, ‘Karotan’ was least applicable to processing since, irrespective of the processing method, the lowest decrease in nitrates was reported for that cultivar. The consumption of processed foods from the cultivars of carrot studied is not hazardous to consumer health, since the value of the ADI in adult, Acceptable Daily Intake, is not exceeded.

Open access

Tomasz Knapowski, Wojciech Kozera, Jarosław Chmielewski, Damian Gorczyca, Elżbieta Wszelaczyńska and Jarosław Pobereżny

Abstract

In Poland, in recent years, there has been a great interest in growing spelt wheat. This is dictated not only by an increasing demand for food with higher healthy properties and unique taste, but also by a possibility of attracting farmers’ attention to this cereal as an alternative crop, with smaller requirements regarding the use of fertilization, as compared with common wheat. The aim of this study was to carry out the assessment of value of some technological characters of grain and flour of spelt wheat depending on different fertilizations with nitrogen (I factor, n=3, 25 and 50 kg N∙ha−1 + control treatment) and foliar application of microelements (II factor, n=4, Mn, Cu, combined fertilization with Mn and Cu + control treatment). Based on the performed study, it was found that fertilization with nitrogen, microelements and their interaction had, on average for years, a significant effect on the values of technological characters. Introduction of 25 kg N·ha−1 caused an increase in the value of falling number, whereas total protein content, wet gluten content and sedimentation value increased as a result of increasing nitrogen rates up to a level of 50 kg·ha−1. Of the variants of fertilization with microelements, the highest values of the analysed baking indices were found in the effects of combined foliar application of copper and manganese.

Open access

Jarosław Pobereżny, Elżbieta Wszelaczyńska, Jarosław Chmielewski, Damian Gorczyca, Wojciech Kozera and Tomasz Knapowski

Abstract

The factors that affect the value of parsley for consumption include its taste, flavour and dietary utility (vitamins C and E, β-carotene, potassium, calcium, phosphorus and iron, raw fibre, proteins) as well as the content of hazardous substances, especially nitrogen compounds. A study was carried out in 2013–2015 to determine the effect of the cultivation technology and storage on the safety of parsley intended for processing. The study material was taken from an experiment where the following fertilisers were applied to the ground: nitrogen (0, 40, 80, 120 kg N∙ha−1) and magnesium (0; 30 kg Mg∙ha−1). Parsley roots were stored for six months in a storage room at +1°C and RH 95%. The content of nitrates (V) and (III) was determined by the ion selective method immediately after the harvest and after storage in parsley roots.

The highest levels of nitrates (V) and (III) were found in parsley roots in the cultivation option where nitrogen for fertilisation was applied at the greatest amount, i.e. 120 kg N ha−1 and magnesium at 30 kg Mg∙ha−1. Regardless of the measures applied during the vegetation period, prolonged storage of parsley resulted in a decreased content of nitrates (V) and (III) in its roots. The limit for nitrogen content and the acceptable daily intake (ADI) for nitrates (1.0%) and nitrites (4.5%) were not exceeded in the cultivar under study.

Open access

Marcin Weiner, Wioletta Żukiewicz-Sobczak, Małgorzata Tokarska-Rodak, Dorota Plewik, Anna Pańczuk, Marta Siłuch, Jerzy Zagórski, Paweł Sobczak, Tomasz Chmielewski, Stanisława Tylewska-Wierzbanowska, Mariia Shkilna, Mykhailo Korda, Ivan Klisch, Mykhailo Andreychyn and Mariana Pavliuk

Abstract

Introduction: Lyme borreliosis/Lyme disease is caused by Borrelia burgdorferi and is one of the most common vector-borne diseases transmitted by ticks.

Material and Methods: A total of 136 Ixodes ricinus ticks, collected in the Ternopil (Ukraine) region, including 126 adults (70 females and 56 males), and 10 nymphs were examined. The identification of the species and their developmental form was based on morphological characteristics.

Results: PCR with B5S-Bor and 23S-Bor primers resulted in Borrelia burgdorferi sensu lato DNA amplification among six ticks (4.4%). The detailed analysis based on the DNA sequencing showed the presence of DNA of Borrelia afzelii in four samples; the remaining two represented Borrelia burgdorferi sensu lato complex, although their genospecies were not determined. The research confirmed the dominance of Borrelia afzelii genospecies in the ticks from Ukraine.

Conclusion: It seems reasonable to undertake similar research in ticks from other regions of Ukraine. Knowledge in this field can be useful for public health and planning the prevention of tick-borne diseases.