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Number of results: 7
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Abstract

The article present the results of use of the proposed economic and mathematical apparatus to develop scenarios that provide for the partial or complete elimination of contradictions associated with the pricing policy between oil and gas production and the production of refined products. In the output we noted changes in the material consumption of products of the oil and gas sector of Ukraine. We corrected a certain contradiction between the extractive and processing enterprises of the oil and gas sector. This is related to the uneven distribution of value added between them, which allows extractive enterprises to make a profit, while processing enterprises are at a breakeven point. This situation, as we have seen, also distorts the results of the real assessment of resource efficiency in this sector of the economy. Thus, the research is aimed at developing scenarios that provide for a gradual decrease in the price of extractive products and its simultaneous growth in processing so that the corresponding impact on the economy was minimal. The first scenario envisaged a reduction in the price by –10% for the products of oil and gas companies with a simultaneous increase in the price of refining so that the average share of value added in the country as a whole was not decreased, taking appropriate adjustments of resource efficiency indicators into account. The second scenario was based on the need for deeper price adjustments in the oil and gas sector. Thus, the reduction of the price of products at the extractive enterprises at the level of –20% and its increase it in processing while maintaining the national average share of value added was envisioned. The third scenario provided for the equalization of material consumption in production and processing due to the price factor.

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Authors and Affiliations

Nadiia Shmygol
ORCID: ORCID
Olena Cherniavska
Tеtіana Pulina
Ruslan Zavgorodniy
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Abstract

The problem of the migration of metal ions in the environment remains a current problem in light of the quality of obtained crops. The necessity of more and more frequent use of alternative sources of biogens in the form of waste substances, poses a threat of loading significant amounts of metals into the soil – including heavy metals harmful to human health and life. The article discusses a significant problem, namely the comparison of the results of the environmental impact of waste, obtained on the basis of legally authorized leaching tests (three-stage leaching test according to PN-EN 12457:2006), with results obtained from sequential chemical extraction (performed in 4-step chemical extraction developed and recommended in European Union countries by Communities Bureau of References – BCR). The study covered an investigation of industry fly ash from the combustion of lignite, in which Cu, Zn, Cd, Ni, Pb, Cr, Na, K, Li concentrations and loads were calculated. A mobility of analyzed elements was established on this basis. From heavy metals, the highest values in fraction I were noted for nickel and copper and zinc as well as nickel were noted for fraction IV . Peaking values of electrolytic conductivity in eluates was created by high concentrations of macroelements (Na and K). These tests confirm that the leaching tests used for their application in the natural environment indicate such concentrations at the highest levels that can be obtained at the first or second stage of sequential chemical extraction, and thus their proper full environmental impact is not known.

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Authors and Affiliations

Czesława Rosik-Dulewska
ORCID: ORCID
Urszula Karwaczyńska
Tomasz Ciesielczuk
ORCID: ORCID
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Abstract

The article presents the approach to the design process of acoustic panels based on the scientific research. This approach is based on combining the technical and the design competences to develop the innovative product value for the concept of acoustic panels. The article presents the concepts of two new acoustic panels – an absorbing and scattering panel and a panel reflecting sound waves. The first part of the article presents the starting point for the presented project – the acoustic research and the inspiration for both types of presented solutions. Next, the materials possible to use were discussed, which could reproduce the natural acoustic properties of the lava and glacier caves. The next part presents consecutive stages of the product development in a modern form, ensuring the expected acoustic properties. The last part of the article presents a fully functional solution and proposes further research and development directions.
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Authors and Affiliations

Bartłomiej Borkowski
1
Katarzyna Suder-Dębska
2
Jerzy Wiciak
1
Anna Maria Szlachta
3

  1. Department of Mechanics and Vibroacoustics, AGH – University of Science and Technology, Kraków, Poland
  2. Department of Power Systems and Environmental Protection Facilities, AGH – University of Science and Technology, Kraków, Poland
  3. Faculty of Industrial Design, Jan Matejko Academy of Fine Arts, Kraków, Poland
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Abstract

The arc suppression coil determines whether it can effectively extinguish the arc when it is grounded in the neutral non-effective grounding system. An artificial grounding test is an importantway to verify its performance. In this study, 13 substations with the 10 kV system in the Ningxia areawere selected and considered. Based on the artificial single-phase grounding test, the residual current, the compensation current and the off-resonance degree were measured in the arc suppression coil, and the performance of the arc suppression coil in the 10 kV system was verified. The experimental results show that the error of arc suppression coil automatic measurement is large, the off-resonance degree is large, the resistive component in the compensation current is excessive, the harmonic component exists in the compensating current and capacitive current. To solve these problems, this paper puts forward the corresponding countermeasures for reference.

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Authors and Affiliations

Hui Ni
Pei Ding
Yunlong Ma
Shaogui Ai
Feiyue Ma
Qingping Zhang
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Abstract

The paper presents an approach to identify the state of fine sands on the basis of shear wave velocity measurement. Large body of experimental data was used to derive formulae which relate void ratio with shear wave velocity and mean effective stress for a given material. Two fine sands which contained 8 and 14% of fines were tested. The soils were tested in triaxial tests. Sands specimens were reconstituted in triaxial cell. In order to obtain predetermined void ratio values covering possible widest range of the parameter representing a very loose and dense state as well, the moist tamping method with use of undercompaction technique was adopted. Fully saturated soil underwent staged consolidation at the end of which shear wave velocity was measured. Since volume control of a specimen was enhanced by use of proximity transducers, representative 3 elements sets (i.e. void ratio e, mean effective stress p’ and shear wave velocity VS) describing state of material were obtained. Analysis of the test results revealed that relationship between shear wave velocity and mean effective stress p' can be approximated by power function in distinguished void ratio ranges. This made possible to derive formula for calculating void ratio for a given state of stress on the basis of shear wave velocity measurement. The conclusion concerning sensitivity of this approach to the fines content was presented.

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Authors and Affiliations

Mirosław J. Lipiński
Małgorzata K. Wdowska
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Abstract

Moulting southern elephant seals, Mirounga leonina (L.), were counted in 17 discrete wallows at Walker Bay on Livingston Island in the South Shetland Islands between 2 January and 16 February 1994. Daily weather conditions were also recorded. It was also found that, although there were no overall correlations between wind scale, air temperature, sunshine, precipitation, sea roughness and cloud cover with seal numbers, there were conditions on specific days that affected the movements of seals between wallows. Most notably, it was found that numbers of seals decreased when they were exposed to winds, and that they often sought out more sheltered sites nearby.

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Authors and Affiliations

Elizabeth Cruwys
Pamela B. Davis
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Abstract

Petrographic and physico-chemical analyses of ashes are carried out on a large scale and presented in numerous scientific papers. The mentioned ashes are obtained from filters and electrostatic precipitators mounted in large industrial installations. The large-scale analysis of the ashes obtained directly from grate furnaces or blast furnaces mounted in low-power boilers started with combating smog and low-stack emissions. The collection of ash samples from household furnaces usually involves the analysis of the combustion of waste in low-power boilers. This is justified in the case of old type boilers, which were designed to use virtually any fuel. Currently, new types of boilers, designed to burn dedicated fuels, are offered on the market. The aim is to use only renewable fuels (biomass) or fossil fuels with high quality parameters, which are more environment-friendly, e.g. eco-pea coal, lignite briquettes, or peat briquettes. The authors of the study focused on examining the ash obtained from boilers for burning wood pellets by performing microscopic analysis of residues after biomass combustion. The above mentioned analysis provides a comprehensive information on the efficiency of the combustion process, the content of contaminants remaining in the ash, and the suitability of ash for other applications. The entire process, from the moment of collecting the samples to the execution of the analysis takes up to 12 hours, which ensures a quick decision on furnace adjustment or fuel change. The ash components were determined based on the results obtained by the Fly-Ash Working Group of the International Committee for Coal and Organic Petrology (ICCP). The mentioned classification has been supplemented with new key elements occurring in ashes resulting from the combustion of wood pellets in household boilers. This allowed determining the percentage content of characteristic components in the tested material, which can be used as a specific benchmark when issuing opinions on the quality and efficiency of the boiler and the combusted pellets.

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Authors and Affiliations

Zbigniew Jelonek
Adam Nocoń
Iwona Jelonek
Marta Jach-Nocoń

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