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  • Author: V. A. Kovalenko x
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Abstract

Carbon-copper composite coatings reinforced with titanium were deposited using high power magnetron sputtering technique. Tribological and metrological tests were performed using Taylor Hobson Talysurf Intra 50 measuring equipment and CSM Instruments ball-on-disk type tribometer. Friction coefficient and wear rate were determined at 2N, 4N, 6N loads. It was revealed that friction coefficient decreased at a higher Ti concentration, which was particularly expressed at bigger applied loads. However, wear volume values tended to increase in the beginning, till Ti concentration reached about 11 %, but then decreased, thus providing better nanocoating wear resistance.

Abstract

Abundance and distribution of nematodes of the genus Trichuris Schrank, 1788 parasitizing domestic sheep (Ovis aries Linnaeus, 1758) were studied in Poltava, Kyiv and Zaporizhzhia Regions of Ukraine. Three species of Trichuris were found, Trichuris skrjabini Baskakov, 1924, Trichuris ovis Abildgaard, 1795 and Trichuris globulosa Linstow, 1901. Trichuris ovis and T. skrjabini were more common (54.9 and 35.7 %), whereas T. globulosa was relatively rare (9.4 %) in the studied material. New species-specific and sex-related morphological characters and metric indices were reviewed as useful in better identification of T. skrjabini, T. ovis and T. globulosa parasitizing sheep.

Abstract

The analysis of the current state of weather and climatic conditions and evaluation of their predicted changes for immediate and distant prospect in the drained areas of Ukrainian Polissia region was carried out in the article. The main trends in changes of meteorological characteristics and their possible effect on the conditions of functioning water management and ameliorative objects and complexes as well as on the natural and ameliorative state of drained areas were identified. The research uses a method of predictive-simulation modelling with used predictive assessment models of normalized distribution of the basic meteorological characteristics in the long-term and one-year vegetation context. According to the results of the research it was established that, for today a high variability in meteorological characteristics can lead to the significant deterioration of operation conditions of water management and ameliorative objects and units, as well as natural and ameliorative conditions of drained lands in Polissia region as a whole. Core measures regarding the adaptive potential enhancement and development in the region under the conditions of climate change were examined.