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Number of results: 7
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Abstract

The article analyzes the risk factors related to the energy use of alternative fuels from waste. The essence of risk and its impact on economic activity in the area of waste management were discussed. Then, a risk assessment, on the example of waste fractions used for the production of alternative fuel, was carried out. In addition, the benefits for the society and the environment from the processing of alternative fuels for energy purposes, including, among others: reducing the cost of waste disposal, limiting the negative impact on water, soil and air, reducing the amount of waste deposited, acquisition of land; reduction of the greenhouse effect, facilitating the recycling of other fractions, recovery of electricity and heat, and saving conventional energy carriers, were determined. The analysis of risk factors is carried out separately for plants processing waste for alternative fuel production and plants producing energy from this type of fuel. Waste processing plants should pay attention to investment, market (price, interest rate, and currency), business climate, political, and legal risks, as well as weather, seasonal, logistic, technological, and loss of profitability or bankruptcy risks. Similar risks are observed in the case of energy companies, as they operate in the same external environment. Moreover, internal risks may be similar; however, the specific nature of the operation of each enterprise should be taken into account. Energy companies should pay particular attention to the various types of costs that may threaten the stability of operation, especially in the case of regulated energy prices. The risk associated with the inadequate quality of the supplied and stored fuels is important. This risk may disrupt the technological process and reduce the plant’s operational efficiency. Heating plants and combined heat and power plants should also not underestimate the non-catastrophic weather risk, which may lead to a decrease in heat demand and a reduction in business revenues. A comprehensive approach to risk should protect enterprises against possible losses due to various types of threats, including both external and internal threats.

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Authors and Affiliations

Oleksandr Ivashchuk
Bartosz Łamasz
Natalia Iwaszczuk
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Abstract

The geochemistry of sedimentary rocks is increasingly being used in palaeoenvironmental studies, in the identification of marine versus continental stratigraphy and in chemostratigraphic correlation. The selection of an appropriate research methodology, particularly in terms of sample digestion, can have a significant impact on the accuracy of the results obtained. Depending on the type of rock being studied and the aim of the analysis, a suitable mixture of acids should be used. The most commonly used sample digestion methods are based on a mixture of four acids (multi-acid), aqua regia and inverse aqua regia. As opposed to multi-acid whole-rock digestion, the use of aqua regia and inverse aqua regia result in only the partial digestion of sedimentary rocks. Geochemical analyses using these two different methods were carried out on Carboniferous sedimentary rocks from the Lublin Coal Basin from Poland.The elemental concentrations obtained showed essentially different results for some of the elements. A comparison of the elemental concentrations allowed the distinction of three groups of elements:

 - those that showed small differences between the results from the preparation methods (Co, Mn, Bi, Cu, Zn and Fe),

- those where the elemental concentrations were 20–50% lower using aqua regia digestion (i.e. Ni, P, Pb, Mg, Cd, Th, Mo, Sr),

 - elemental concentrations that were significantly lower (by up to 80%) following aqua regia digestion (U, Cr, Ba, Na, V, Al, Rb, K, Zr).

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Authors and Affiliations

Ewa Krzeszowska
ORCID: ORCID
Magdalena Kokowska-Pawłowska
ORCID: ORCID
Światosław Krzeszowski
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Abstract

Vibro-acoustic response of an isotropic beam under the action of variable axial loads (VALs), is presented in the study. Effects of six different types of VALs and three types of end conditions on buckling, free vibration and sound radiation characteristics are investigated. Static buckling and free vibration behaviours using shear and normal deformable theorem and Ritz method. However, the forced vibration response is evaluated using modal superposition method and the acoustic radiation characteristics are obtained using Rayleigh integral. The nature of variation of VALs and end conditions are influencing buckling and free vibration characteristics remarkably. Results indicate that the acoustic response is highly sensitive to the nature of VAL and intensity of the VAL. In general, sound power at resonance decreases when the magnitude of VAL is increased.
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Authors and Affiliations

Somi Naidu Balireddy
1
Jeyaraj Pitchaimani
1
Lenin Babu Mailan Chinnapandi
2
V.S.N. Reddi Chintapalli
3

  1. National Institute of Technology Karnataka Surathkal, Mangalore 575 025, India
  2. Vellore Institute of Technology Chennai, Tamilnadu 600 127, India
  3. Aditya Engineering College, Surampalem, Andhra Pradesh, India
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Abstract

Allelopathy refers to the beneficial and detrimental effects of one plant on another plant in both crops and weeds through the production of secondary compounds. In order to evaluate the allelopathic effects of wheat ( Triticum aestivum L.) as a crop and redroot pigweed ( Amaranthus retroflexus L.) as a common weed worldwide on each other in intercropping, these plants were cultivated under controlled conditions at Tabriz University laboratory. The ratios of wheat to redroot pigweed were, 100 : 0 and vice versa as a control, 75 : 25, 50 : 50, and 25 : 75. The results showed that at the ratio of 25 : 75 (wheat : redroot pigweed), the fresh and dry weight of roots and shoot length of wheat decreased significantly compared to the control. The fresh and dry weight of wheat shoots showed a significant decrease at different ratios compared to the control. Shoot peroxidase (POD), root superoxide dismutase (SOD), and root and shoot catalase (CAT) activities in redroot pigweed increased in all intercropping ratios compared to the control. POD activity in wheat roots was higher at all ratios than in the control. Furthermore, the ratio of 75 : 25 (wheat : redroot pigweed) led to increased activity of POD enzymes and malonedialdehyde (MDA) content in wheat shoots. Moreover, roots of redroot pigweed showed increased activity of ascorbate peroxidase (APX) and SOD enzymes and MDA content. With increased density of redroot pigweed, the soluble sugar content of wheat roots reduced significantly. However, the content of insoluble sugar and total protein increased. Root exudate compounds such as terpenoids, phenolic compounds, fatty alcohol, steroids, fatty acids, and alkanes were identified using gas chromatography/mass spectrometry (GC/MS). The findings showed that the roots were more exposed to oxidative stress due to direct contact with allelochemical compounds. Our results support the hypothesis that increasing the density can reduce the toxicity of allelochemical compounds and that increasing the activity of the antioxidant system will improve plant growth under allelochemical stress.
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Authors and Affiliations

Zahra Alizadeh
1
ORCID: ORCID
Rouhollah Motafakkerazad
1
ORCID: ORCID
Seyed Yahya Salehi-Lisar
1
Gholamreza Zarrini
2

  1. Plant, Cell and Molecular Biology Department, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
  2. Animal Biology Department, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
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Abstract

The paper presents the method of simplified parametric analysis of the sensitivity of a pre-tensioned concrete beam. The presented approach is based on the DOE (design of experiments) data collection which is simulation technique allowing for identification of variables deciding about the effectiveness and costs of designed structures. Additionally, application of the hyper-surface of the construction response allows designers to the development of multi-dimensional trade-off graphs to facilitate, the assessment of the scope of changes in random state variables permitted due to the adequate criteria and selection of their values close to optimum. Design basics, procedures and results of the presented considerations of sensitivity assessment and reliability of the structure has been shown on the example of a pre-stressed concrete beam designed in accordance with the requirements and procedures of Eurocode 2.

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Authors and Affiliations

Sz. Woliński
T. Pytlowany
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Abstract

Bacterial, enzymatic and chemical analyses pointed to active microbiological mineralization and transformation of penguin excrements at "maritime Antarctic". The following physiological groups of bacteria were found: proteolitic, amonifying, nitrifying, lecithin degrading, Са3(Р04 ) 2 dissolving, chitin degrading and spore forming ones. The number of molds was not significant. The nitrate reducers and N2 — fixing bacteria were not detected. About 50% of С and N were volatilized during three weeks. Some parts of N — NH3 was oxidized to N — NO3 in surface layer of the soil. The content of P increased during degradation of penguin excrements. About 1/3 part of total organic carbon content in bird excrements residues was derived from chitin.

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Authors and Affiliations

Stanisław J. Pietr
Andrzej Tatur
Andrzej Myrcha
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Abstract

Inspired by the Chicago School sociology and anthropology of Mary Douglas authors of the article show the special cultural status of new urban peripheries in comparison to villages, old urban peripheries and city centers. Critically they relate to the thesis that new urban peripheries are “cultural deserts” or “bedroom/dormitory suburbs”, considering them as a form of collective organization or sustained activity patterns that replace an original kind of culture. According to Mary Douglas villages are characterized by low level of social energy and high degree of collective control, and the city centers are characterized by high level of energy and low collective control. Referring to this classification the authors of the paper claim that new urban peripheries are characterized by both low energy and low collective control. A more detailed characterization of a new urban periphery is presented in the article on the basis of materials collected in several qualitative sociological research projects. In the light of the empirical material, it can be revealed that in new urban peripheries direct forms of collective control have been replaced by social non-interference, development of individualistic self-control and privatization of micro-spaces of living and transporting. It was noted that the intensive development of individualized outdoor activity leads to gradual formation of the new body type of a new urban periphery resident.

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Authors and Affiliations

Dorota Rancew-Sikora
ORCID: ORCID
Lesław Michałowski
Bogna Dowgiałło

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