Ocean Thermal Energy Conversion (OTEC) is one of the emerging industries of ocean energy and an important link in carbon neutrality. Turbine is a key component of ocean thermal energy conversion, which has an important impact on the performance and energy conversion efficiency of the system. This paper fully considers the application characteristics of ocean thermal energy conversion and the state conversion characteristics of ammonia working fluid. Taking the 100 kW radial inflow turbine in the OTEC application system as an example, based on the design, the turbine is optimized for the key parameters of the turbine stator and the influence of different geometric parameters is analyzed. Subsequently, the optimization results are verified by CFD numerical simulation analysis under different conditions. The results show that the number of stator blades has an important influence on the performance of the turbine. Further optimization studies have shown that through optimization, when the number of stator blades is 33, the internal flow field performance is the best, and the working conditions of the inlet and outlet working fluids are in accordance with the design points without obvious shock wave and reverse flow phenomenon, the efficiency is 89.46%, 3.94% higher than the design value.

The aim of the study was to evaluate the pregnancy rate after application of the OvSynch (OVS) programme depending on the reliability of the programme implementation and the number of cows treated at the same time. Taking into account the reliability of the programme, cows were divided into five groups. Females in group I were inseminated after the initial dose of GnRH, i.e. 1-6 days after the start of the programme, in group II – on days 7-9 of the OVS protocol, after administration of prostaglandin, in group III – on day 10, after completion of the full OVS protocol and timely insemination, and in group IV – on days 11-12, after completion of the full protocol and insemination according to estrous symptoms. Cows in group V were inseminated at a later period. Additionally, cows were divided into VI groups depending on the number of animals treated simultaneously during the periodic veterinary visit. Groups A, B, C, D, E and F consisted respectively of 1, 2, 3, 4, 5 and 6 cows treated on the same day. Examination for pregnancy was performed twice – on the 28th and 56th day after insemination using an iSkan ultrasound device (Draminski) equipped with a 7.5 MHz linear probe. Large differences in mating rates were shown between farms. Taking into account the timely execution of the OvSynch programme, the highest – 42.3% – mating rate was recorded in cows in which the OVS programme was executed correctly. In the other groups it was significantly (P<0.05) lower. In the case of simultaneous OvSynch in 6 cows, the percentage of correctly executed programs amounted to 83.3% and was significantly higher than in the case of treatment at smaller groups. Using the OvSynch program, the highest pregnancy rates are guaranteed by timely administration of the prescribed injections and insemination at the appointed time. Deviation from the protocol results in a worsening of the pregnancy rate. A higher number of treated cows guaranteed a higher percentage of correctly executed OvSynch programmes. Reasons for this situation were discussed.

To ensure intensive early spring development of bee colonies in the natural lands of Polissya Zhytomyr region in the winter-spring period it is necessary to feed stimulating food. Therefore, the aim of the work is to study the influence of spring feeding with sugar-honey dough on the development and honey productivity of bee families of Ukrainian breed in conditions of clean and radioactively contaminated natural lands of Zhytomyr Polissya. The influence of feeding bee colonies with sugar-honey dough (powdered sugar, centrifuged honey, water) using pure and radioactively contaminated honey on the intensity of development and honey productivity was studied. To do this, two groups were created with experimental families of Ukrainian bee breeds, selected on the principle of analogs, one of which was in a radioactively clean area, and the other in radioactively contaminated soils 137 Cs within 15 Ki/km² and above. A comparative assessment of the early spring development of families was made: from March 16 to May 20, with an interval of 21 days, the number of open and sealed brood, egg production of queens during the honey harvest season was determined. Honey productivity at the honey harvest from natural lands was determined by the amount of honey obtained in spring and summer. Early spring feeding with sugar-honey dough promotes intensive development of families, and the content of radioactively contaminated honey does not have a negative impact on their development. After the end of the season of honey collection from natural lands, bee families of Ukrainian breed, both in the radioactively contaminated and clean zone, had a medium strength and could successfully overwinter.

The paper presents an analysis of the relationship between the variability of sea surface temperature anomalies (SSTa) in the areas of autumn-winter migrations of young Pacific salmon from Eastern and Western Kamchatka and the dynamics of the number of catches of their producers. The series of observations includes the period 1971–2020. The SSTa data collection site covers the waters of the western part of the Bering Sea, the southern part of the Sea of Okhotsk and the northwestern part of the Pacific Ocean. The results of the studies showed that in the areas of mass feeding of juvenile pink salmon, chum salmon and sockeye salmon, the SSTa indicators have a stable relationship with the number of catches of these species. Most of the reliable relationships are indicated by moderate correlation coefficients at the level of r = 0,30–0,60. The pattern is observed for all salmon species in a significant part of the considered water area in the autumn period (September-October). In winter, the relationship is observed much less frequently. It is proposed to use the accumulated SSTa series for multidimensional modeling In addition, the promptly obtained SSTa data in the autumn period of the year preceding the year of fishing, will allow using this indicator as an indicator information characterizing the conditions of feeding of juvenile salmon

Building scaffoldings are temporary structures that are commonly used in the construction industry. A precise determination of the number of building scaffoldings in use is a very complex task. The literature survey showed that there is a lack of scientific studies concerning the estimation of the scaffolding population in the construction industry. This observation gave rise to the need to undertake such research, the aim of which was to develop a model of a neural network set which would in turn enable the number of used building scaffoldings to be estimated. In order to carry out such a research task, an original research methodology was developed, which used the results of empirical research that involved the counting of construction scaffoldings used in selected representative areas of the studied regions of Poland (the research was carried out in the period from 2016 to 2018), and also data taken from a publication of the Central Statistical Office on socio-economic indicators that characterize the analyzed regions (data from 2010 to 2018). The main element of the developed methodology is a set of five MLP neural networks, which was used to predict the number of used construction scaffoldings. The analysis of the sensitivity of the quantitative and qualitative variables of the model showed that they have a significant impact on the final result generated by the networks. The obtained results of the research and analyses showed the size of the population of building scaffoldings used in individual regions of Poland, and also the seasonality of their occurrence. The knowledge obtained on this basis can be used, among others, in economic analyses related to the use of construction scaffolding, as well as in the process of managing occupational safety on scaffoldings. The most important scientific aspect of the article concerns the development of an original methodology for estimating the population of building scaffoldings.

The materials for this article were collected on the territory of many regions of Ukraine. This period was characterized by intensive dispersal of the beaver and the formation of new habitats

The purpose of the study was to establish the strength and general pattern of correlations between quantitative traits that form vegetative and seed productivity in white lupine. Research methods used included field, weighing and measuring, and mathematical and statistical methods. A significant positive correlation was found between the average strength of seed productivity and such traits as plant height, number of lateral shoots, number of beans from central and lateral clusters, etc. A strong positive correlation was detected with the vegetative development of plants, and a weak one with the number of seeds per bean and the weight of 1000 seeds. A significant strong positive correlation of vegetative productivity with such quantitative traits as the weight of beans from the central cluster and the weight of leaves and stems was established. A positive correlation of average strength was found with the number of beans from central and lateral clusters, weight of beans from lateral shoots, root weight, etc. It was found that the seed productivity of white lupine plants is mainly conditioned by the development of such traits as the number of beans from lateral clusters, weight of leaves and roots, number of seeds and weight of seeds from the central and lateral clusters. The formation of vegetative productivity primarily depends on the weight of beans from the central cluster and the weight of leaves and stems. The use of the established regularities of productivity formation will enhance the effectiveness of the selection of selective material according to the specified parameters

Field experiments were carried out at the Department of Agronomy of the Poznań University of Life Sciences to determine the effect of the depth of NP fertilization placement in maize cultivation on the number of plants after emergence. The adopted assumptions were verified based on a six-year field experiment involving four depths of NP fertilizer application (A1—0 cm (broadcast), A2—5 cm (in rows), A3—10 cm (in rows), A4—15 cm (in rows)). The objective of this study was to assess NP fertilizer placement depth, in conjunction with the year, on the number of maize (<i>Zea mays</i> L.) plants after emergence using the additive main effects and multiplicative interaction model. The number of plants after emergence decreased with the depth of NP fertilization in the soil profile, confirming the high dependence of maize on phosphorus and nitrogen availability, as well as greater subsoil loosening during placement. The number of plants after emergence for the experimental NP fertilizer placement depths varied from 7.237 to 8.201 plant m⁻² during six years, with an average of 7.687 plant m⁻². The 61.51% of variation in the total number of plants after emergence was explained by years differences, 23.21% by differences between NP fertilizer placement depths and 4.68% by NP fertilizer placement depths by years interaction. NP fertilizer placement depth 10 cm (A3) was the most stable (ASV = 1.361) in terms of the number of plants after emergence among the studied NP fertilizer placement depths. Assuming that the maize kernels are placed in the soil at a depth of approx. 5 cm, the fertilizer during starter fertilization should be placed 5 cm to the side and below the kernel. Deeper NP fertilizer application in maize cultivation is not recommended. The condition for the use of agriculture progress, represented by localized fertilization, is the simultaneous recognition of the aspects of yielding physiology of new maize varieties and the assessment of their reaction to deeper seed placement during sowing.

Punica granatum L. is one of the oldest known edible fruits. Numerous chemical compounds have been isolated from pomegranate seeds, juice, and peels, which have beneficial effects on human health. This study aimed to perform the physicochemical and morphological properties of twenty-four pomegranate genotypes from various provinces of Iran. Fifteen fruits of each cultivar are collected at harvest maturity in the normal ripening period for the pomegranate from the Iranian pomegranate genetic collection in Yazd, Iran. Five fruits were randomly harvested from each of four orientations of the tree, and were immediately taken to the laboratory for analysis. Three replicates were maintained for each analysis. The results indicated the highest levels of anthocyanin was observed in S783 and R633, while polyphenols in Q529, the antioxidant capacity in N755 and the total soluble solids levels in R633 and the total acidity levels were found in K477 and E336. On the other hand, the fruit weight (in S948), fruit diameter (in SH1738), crown diameter (in R533), total weight of the seeds (in S948), peel thickness (in S716), peel colour (in S948), and red juice (in S783) are significantly affected by the genotype. At a similarity of 50%, the genotypes were divided into nine sub-clusters including A, B, C, D, E, F, G, H and I. These identified genotypes can be rolled out in future breeding programmes.

The ongoing climate warming affects, among others, and the variability of thermal conditions in spring and autumn are resulting in earlier dates of the beginning and end of the growing season. The present paper provides detailed characteristics of the phenomenon of ground frosts, addressing the question of whether the risk of frost-related damage in the extending growing season is still present. The assessment of temporal and spatial distribution of ground frosts (5 cm above ground level-AGL) in Poland in the thermal growing season (AT > 5 °C) was conducted on the basis of the results of air temperature measurements at 5 and 200 cm a.g.l. obtained from 52 station of the Institute of Meteorology and Water Management—National Research Institute for the period 1971–2020. The thermal growing season was calculated using the method by Gumiński. The following were calculated: the dates of the occurrence of ground frosts in spring and autumn, duration of the frost-free period, the number of days with frosts of various intensity, according to years, ten-day period and days in a year together with trends of change. The conducted analysis demonstrated that the number of days with frosts in the thermal growing season in the multiannual period under analysis (1971–2020) does not show any statistically significant changes. It was found that in the thermal growing season, the average number of days with ground frosts in Poland amounts to 28 and ranges in spring from 15 to 22, and in autumn from 8 to 12. Most frequently, approx. 49%, slight frosts are recorded, followed by moderate (29%), severe (15%) and very severe (7%). A positive effect of water reservoirs on decreasing the frequency and intensity of frosts, as well as sporadic occurrence of the phenomenon in the second half of June were demonstrated. Statistically significant earlier dates of disappearance of frosts in spring, later dates of occurrence in autumn and the lengthening of the frost-free period from approximately 2 days in the north-east of Poland to approximately 8.0 days over 10 years in the Pomerania region, create increasingly more favourable conditions for the cultivation of plants with high thermal requirements in Poland.