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Number of results: 13
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Abstract

The efficient, stable and reliable operation of the blast furnace secures the proper quality of coke, which is one of the basic components of the blast furnace charge. In modern blast-furnace technology, when using substitute fuels, i.e. coal dust, the role of coke is extremely important. For this reason, the demands placed on its quality increase. Domestic coking plants have a limited base of Polish high quality coking coals at their disposal, therefore the full use of their coking properties is extremely important. The grain composition of the coal blend is one of the basic factors affecting the quality of the produced coke. This influence depends on the quantity and quality of coal components that make up the blend. In the conducted research, 21 coking coals, differing significantly in the degree of rank and origin (Polish and overseas coals), it was shown that the separated grain classes differ in properties, both coking properties and the degree of devolatalization during heating. In analyzing the obtained results, it was observed that the grain volume growth occurs essentially in the temperature range between the beginning and the maximum of fluidity. It has been shown that there is a linear correlation between the temperature corresponding to maximum fluidity and the temperature at which the maximum rate of evolution of volatiles enters. The presented phenomena accompany the emergence of coal expansion pressure during the coking process and they are its primary causes. The presented results can be an important guide for preparing the milling of coal for the coking process.
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Abstract

The “second generation” of glyphosate-tolerant soybean (GT2 soybean) was developed through a different technique of insertion of the glyphosate-insensitive EPSPs gene, in comparison with “first generation” of glyphosate-tolerant soybean. However, there is not enough information available about glyphosate selectivity in GT2 soybean and the effects on the quality of seeds produced. The aim of this study was to evaluate tolerance to glyphosate and seed quality of soybean cultivar NS 6700 IPRO (GT2) with cp4-EPSPs and cry1Ac genes, after application at post-emergence (V4). The experiment was conducted in a randomized block design with four replicates and seven treatments, or rates of glyphosate (0; 720; 1,440; 2,160; 2,880; 3,600; 4,320 g of acid equivalent − a.e. · ha−1). Assessments were performed for crop injury, SPAD index and variables related to agronomic performance and seed quality. A complementary trial with the same cultivar and treatments in a greenhouse was conducted in a completely randomized design with four replications. Data analysis indicated no significant effect of glyphosate on V4 on agronomic performance and physiological quality of seeds, for two growing seasons. The soybean cultivar NS 6700 IPRO (GT2), with cp4-EPSPs and cry1Ac genes, was tolerant to glyphosate up to the maximum rate applied (4,320 g a.e. · ha−1) at post-emergence (V4). The quality of soybean seeds was not affected by glyphosate up to the maximum rate applied (4,320 g a.e. · ha−1) at post-emergence (V4).
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Abstract

The possibility of producing 3-aminobenzyl alcohol and 3-aminobenzaldehyde by oxidation of 3-aminotoluene with ozone in the solution of acetic anhydrite in the presence of manganese (II) acetate, potassium bromide and sulfuric acid has been shown. The catalytic systems for regulating selectivity and depth of substrate oxidation has been developed. The catalytic system Mn(OAc)₂ – Ac₂0 – H₂SO₄ promotes the formation of alcohol (65.5%) and 3- acetylaminobenzylidendiacetate (20.1%) with the system Mn(OAc)₂ – KBr – Ac₂O – H2SO₄ increases oxidation selectivity on the methyl group to 90.8% producing mainly aldehyde (80.8%) The optimum temperature of selective oxidation of 3– aminotoluene with the ozone – air mixture (30°C) which is much lower than that of oxidation by the known methods (120°-240°C) and the optimum rations of the reagents concentrations: for alcohol synthesis – [ArCH3] : [Mn(OAc)₂] : [H₂SO₄] =1 : 0.2 : 2.5; for aldehyde synthesis –[ ArCH3]: [Mn(OAc)₂] : [KBr] aldehyde synthesis – [ArCH3] : [Mn(OAc)₂] : [KBr] : [H₂SO₄] = 1:0.2:2.5 have been determined.
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Abstract

Control failure of pests and selectivity of insecticides to beneficial arthropods are key data for the implementation of Integrated Pest Management (IPM) programs. Therefore, the aim of this study was to assess the control failure likelihood of Plutella xylostella and the physiological selectivity active ingredients to parasitoid Oomyzus sokolowskii (Hymenoptera: Eulophidae) and to predators Polybia scutellaris (Hymenoptera: Vespidae) and Lasiochilus sp. (Hemiptera: Anthocoridae). In bioassays, P. xylostella larvae and O. sokolowskii, P. scutellaris and Lasiochilus sp. adults were used. Concentration-mortality curves of six insecticides for P. xylostella were established. These curves were used to estimate the mortality of P. xylostella at the recommended concentration, in order to check a control failure of insecticides to this pest. Furthermore, the lethal concentration for 90% of populations (LC90) and the half of LC90 were used in bioassays with the natural enemies to determine the selectivity of these insects to insecticides. All tested insecticides showed control failure to P. xylostella, indicated by high LC90 and low estimated mortalities (less than 80%). The cartap insecticide was selective in half of LC90 to Lasiochilus sp. and moderately selective in LC90 and the half of LC90, to Lasiochilus sp. and P. scutellaris, respectively. Deltamethrin was moderately selective in the half of LC90 to predator Lasiochilus sp. Cartap, carbaryl, and deltamethrin reduced the mortality of Lasiochilus sp. in the half LC90. The results also showed that the insecticides methamidophos, carbaryl, parathion methyl and permethrin were not selective to any of the tested natural enemies. The role of insecticides in IPM systems of Brassica crops is discussed based on their control failures to P. xylostella and selectivity to their natural enemies.
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Abstract

The avifaunistic observations carried out in the tundra valley of the Sob River's upper course (west slopes of the Polar Ural) in July 1995 revealed the occurrence of 39 breeding and 8 non-breeding bird species. The most numerous were Anthus pratensis, Calcarius lapponicus, Phylloscopus trochilus and Anthus cervinus. The great variety of wetland and aquatic habitats had a decisive influence on species-richness and abundance of birds (jointly 30 breeding and 4 non-breeding species). Areas of low humidity were inhabited by 14 whereas anthropogenic habitats by 4 species. Most of them (except for eurytopic A. pratensis and C. lapponicus) occupied one-two habitats irrespective of their numbers. The density of Buteo lagopus was estimated at 1.67-2.00 p/10 km2. Three species of distribution ranges laying to the south from the study area, namely Bucephala clangula, Dendrocopos major, Circus macrourus, were noted in the valley. The results obtained have been compared with available data on the avifauna of the region concerned.
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Abstract

The paper presents the experience of using the ŁPrP, ŁPKO, ŁPSp, ŁPSpA i ŁPSp3R types of flattened supports for longwall entries in the conditions of the JSW S.A. Knurów-Szczygłowice coal mine. The article concentrates on the support solutions applied in the conditions of the mine and the results in terms of stability and usefulness of the structures of the supports. An analysis of the load bearing capacity and technological conditions has been conducted for various flattened supports solutions, with special consideration given to the ŁPSp and ŁPrPJ support sets. Comparing these two, the ŁPSp exhibits a load bearing capacity that is 21% higher while using 31% less steel mass. The experiment results allowed to determine that the ŁPSpA and ŁPSp3R support types are an advantageous solutions in case of longwall set-up rooms.
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Abstract

NHST (null hypothesis significance testing) is the most popular statistical paradigm in psychology. Mistakes in interpretation of its assumptions and their consequences are topic for methodological and statistical discussion for over fifty years. Article presents two problems associated with NHST that are particularly prevalent in psychology: identifying non-significant results with research failure and conducting underpowered research. They can contribute to increase in exploiting questionable research practices in order to obtain desirable, significant outcomes. Three practices: p-hacking, HARKing and selective publishing are described, along with analysis of their impact on replication crisis in psychological science.
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Abstract

This article proposes a model describing the nature of associative processes as diagnostic cues for formulating attitudes and judgments. The assumption of the model is that attitudes, judgments and behaviours are based on how people selectively activate, interpret and integrate previously associated signals (selectively limiting the excess of information from both the senses and from our immediate environment). The model specifies which factors hinder or facilitate the formulation of associations between diagnostic signals and how it translates into attitudes, judgments and behaviours. To test the predictions derived from this model, we first showed that linguistic cues of diminutives can indicate physical properties – they were associated with the belief that the described objects were smaller but also worse or less valuable. The second line of research dealt with embodied moral judgments – we demonstrated that the usage of a hand over heart gesture led to more honest behaviour, an increase in judgments of honesty but also reduced tendency to lie for one's own profit. Our findings also suggest that using “standing at attention” body manipulation increased participants' submissiveness to the experimenter and their obedience to norms. This pattern of results suggests that the described model integrates perspectives of embodied cognition and social cognition, documenting the cognitive mechanism needed to formulate and adjust attitudes and judgments.
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Abstract

Al2Cu phase has been obtained by melting pure metals in the electric arc furnace. It has been found that the intermetallic phase undergoes selective corrosion in the H3PO4 aqueous solutions. Aluminium is dissolved, the surface becomes porous and enriched with copper. The corrosion rate equals to 371 ± 17 g·m–2·day–1 (aerated solution) and 284 ± 9 g·m–2·day–1 (deaerated solution). The surface of Al2Cu phase after selective corrosion was characterised by using electrochemical impedance spectroscopy. It was found that the surface area of the specimens increases with temperature due to higher corrosion rate and is between 2137 and 3896 cm2.
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Abstract

Semiconductive - resistive sensors of toxic and explosive gases were fabricated from nanograins of SnO2 using thick-.lm technology. Sensitivity, selectivityand stabilityof sensors working in di.erent temperature depend on the way the tin dioxide and additives were prepared. A construction also plays an important role. The paper presents an attitude towards the evaluation of transport of electrical charges in semiconductive grain layer of SnO2, when dangerous gases appear in the surrounding atmosphere.
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Abstract

As one of the key techniques in the fully mechanized mining process, equipment selection and matching has a great effect on security, production and efficiency. The selection and matching of fully mechanized mining equipment in thin coal seam are restricted by many factors. In fully mechanized mining (FMM) faced in thin coal seams (TCS), to counter the problems existing in equipment selection, such as many the parameters concerned and low automation, an expert system (ES) of equipment selection for fully mechanized mining longwall face was established. A database for the equipment selection and matching expert system in thin coal seam, fully mechanized mining face has been established. Meanwhile, a decision-making software matching the ES was developed. Based on several real world examples, the reliability and technical risks of the results from the ES was discussed. Compared with the field applications, the shearer selection from the ES is reliable. However, some small deviations existed in the hydraulic support and scraper conveyor selection. Then, the ES was further improved. As a result, equipment selection in fully mechanized mining longwall face called 4301 in the Liangshuijing coal mine was carried out by the improved ES. Equipment selection results of the interface in the improved ES is consistent with the design proposal of the 4301 FMM working face. The reliability of the improved ES can meet the requirements of the engineering. It promotes the intelligent and efficient mining of coal resources in China.
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Abstract

According to the Grant Map of the Ministry of Development (MoD) as of March-April 2017, there were 1716 urban regeneration (revitalization) projects implemented in Poland between 2007-2013. Data from 11 voivodeships (out of 16 regions NUTS 2 in Poland) and 977 projects was sufficient to provide a representative sample (56,9% of projects presented in the Grant Map). The main methods used in the article included observation and review of MoD statistical data and literature on the subject. As observed by the author, between 2007-2013 the definition of urban regeneration (revitalization) was only mentioned in one of the footnotes to the housing guidelines, which was a poor legal basis for the regional managing authorities. Similarly, there was no solid basis in the strategic documents (national) for that period: they did not provide any definition of revitalization. It was in the interest of the beneficiaries, as well as – partly – in the interest of those managing authorities to satisfy the local needs, especially those needs which were not considered the result of the shift to the post-industrial era, but rather as a result of numerous institutional and political events. Due to these features, the period 2007-2013 was dominated by infrastructure projects aimed at the quality of life but also efficient in terms of spending European money. It seems that there was an agreement between regional managing authorities and the benefi ciaries (potential voters) as to the way of spending the revitalization funding. This was understood differently at national level, but because institutions at this level were not involved directly in the urban regeneration (revitalization), their influence on regional units was minor. Even more so because the managing authorities were also interested in speeding up the process of spending European resources.
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Abstract

Spectroscopy has become one of the most used non-invasive methods to detect plant diseases before symptoms are visible. In this study it was possible to characterize the spectral variation in leaves of Solanum lycopersicum L. infected with Fusarium oxysporum during the incubation period. It was also possible to identify the relevant specific wavelengths in the range of 380–1000 nm that can be used as spectral signatures for the detection and discrimination of vascular wilt in S. lycopersicum. It was observed that inoculated tomato plants increased their reflectance in the visible range (Vis) and decreased slowly in the near infrared range (NIR) measured during incubation, showing marked differences with plants subjected to water stress in the Vis/NIR. Additionally, three ranges were found in the spectrum related to infection by F. oxysporum (510–520 nm, 650–670 nm, 700–750 nm). Linear discriminant models on spectral reflectance data were able to differentiate between tomato varieties inoculated with F. oxysporum from healthy ones with accuracies higher than 70% 9 days after inoculation. The results showed the potential of reflectance spectroscopy to discriminate plants inoculated with F. oxysporum from healthy ones as well as those subjected to water stress in the incubation period of the disease.
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