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Number of results: 27
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Abstract

Nickel alloys belong to the group of most resistant materials when used under the extreme operating conditions, including chemically

aggressive environment, high temperature, and high loads applied over a long period of time. Although in the global technology market

one can find several standard cast nickel alloys, the vast majority of components operating in machines and equipment are made from

alloys processed by the costly metalworking operations. Analysis of the available literature and own studies have shown that the use of

casting technology in the manufacture of components from nickel alloys poses a lot of difficulty. This is due to the adverse technological

properties of these alloys, like poor fluidity, high casting shrinkage, and above all, high reactivity of liquid metal with the atmospheric air

over the bath and with the ceramic material of both the crucible and foundry mold. The scale of these problems increases with the expected

growth of performance properties which these alloys should offer to the user.

This article presents the results of studies of physico-chemical interactions that occur between theH282alloy melt and selected refractory

ceramic materials commonly used in foundry. Own methodology for conducting micro-melts on a laboratory scale was elaborated and

discussed. The results obtained have revealed that the alumina-based ceramics exhibits greater reactivity in contact with the H282 alloy

melt than the materials based on zirconium compounds. In the conducted experiments, the ceramic materials based on zirconium silicate

have proved to be a much better choice than the zirconia-silica mixture. Regardless of the type of the ceramic materials used, the time and

temperature of their contact with the nickel alloy melt should always be limited to an absolutely necessary minimum required by the

technological regime.

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Authors and Affiliations

Z. Pirowski
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Abstract

Freedom and Resentment (1962), written by Peter Frederick Strawson, is one of the most influential papers in 20th century investigations regarding the problem of free will. An interesting criticism of that work was proposed by his son, Galen Strawson, who analyzed and rejected his father’s view, called the theory of reactive attitudes. In my paper I reconstruct the views of Peter Strawson and present counterarguments put forward by Galen Strawson. In the summary I suggest, following Robert Kane, that the disagreement may reflect some important changes in analytic philosophy.

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Authors and Affiliations

Jacek Jarocki
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Abstract

Self-esteem and emotional reactivity may be important personality determinants of human functioning in situations of social exposure. In this study, we compared the levels of these personality variables in a group of professional theater actors and a group of professional illusionists with a control group of participants who were neither actors nor illusionists and had no artistic education. We also examined the correlations between emotional reactivity and self-esteem in the three groups. For emotional reactivity, we found (1) very strong evidence that the level is less for magicians than for controls, (2) substantial evidence that the level is less for magicians than for actors, (3) anecdotal evidence that the level is less for actors than for controls, and (4) decisive evidence that the average score is less for males than for females. For self-esteem, we found (1) anecdotal evidence that the level is higher for magicians than for controls, (2) substantial evidence that there is no difference between actors and magicians, (3) anecdotal evidence against a difference between actors and controls, and (4) anecdotal evidence against a difference between males and females. Based on the entire sample we found a moderate correlation between self-esteem and emotional reactivity (r = -.30, p < 0.001). Our results are compatible with the notion that emotional reactivity – as part of the temperament concept – is a factor influencing the choice of an artistic profession.
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Authors and Affiliations

Wojciech Napora
1
Vebjørn Ekroll
2

  1. Jan Dlugosz University in Częstochowa, Poland
  2. University of Bergen, Norway
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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 aims at the higher reactive power management complexity caused by the access of distributed power, and the problem such as large data exchange capacity, low accuracy of reactive power distribution, a slow convergence rate, and so on, may appear when the controlled objects are large. This paper proposes a reactive power and voltage control management strategy based on virtual reactance cloud control. The coupling between active power and reactive power in the system is effectively eliminated through the virtual reactance. At the same time, huge amounts of data are treated to parallel processing by using the cloud computing model parallel distributed processing, realize the uncertainty transformation between qualitative concept and quantitative value. The power distribution matrix is formed according to graph theory, and the accurate allocation of reactive power is realized by applying the cloud control model. Finally, the validity and rationality of this method are verified by testing a practical node system through simulation.

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Authors and Affiliations

Wei Min Zhang
Yan Xia Zhang
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Abstract

Catalytic reforming is an important intermediate in the processing of crude (naphtha in particular) to obtain gasoline. The catalyst used in the process (platinum) is quite expensive and may negatively impact the business if not used judiciously. The aforesaid not only refers to the reduction in loss of the catalyst per unit of gasoline produced but also to the manufacturing of an environmentally friendlier product alongside which is the need of the planet and also a necessity to meet the increasingly strict government norms. In order to meet the above requirements, various refineries around the world use various well-known conventional methods which depend on the quality and quantity of crude manufactured by them.
This paper focuses on highlighting recent advancements in methods of catalytic regeneration (CR) in the reforming unit of petroleum industries to produce high octane gasoline, without any major replacements in their existing setup. Research papers formulated by the application of methodologies involving non-linear models and real-time refinery data have only been considered to avoid any deviations/errors in practical applications. In-depth analysis of these papers has led to the origin of some ideas which have been included as suggestions and can be considered as subjects of further research. In all, the objective of the paper is to serve as a reference for researchers and engineers working on devising optimum methods to improve the regeneration of reforming catalysts.
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Authors and Affiliations

Aviral Gupta
1
S.K. Gupta
1

  1. Harcourt Butler Technical University, Department of Chemical Engineering, Kanpur-208002, India
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Abstract

The paper focuses on two research objectives. First, it aims to critically examine a reductio ad absurdum argument against incompatibilism whose main themes can be found in Peter F. Strawson’s Freedom and Resentment. The doubts raised about the argument are inspired by a thought experiment based on fictitious Ludovico’s technique described in Anthony Burgess’s novel A Clockwork Orange. The second objective consists in outlining a version of the compatibilist stance – the version which is immune to Strawson’s objections against the traditional rendering of compatibilism and enables deeper understanding of various possible interpretations of the controversy between compatibilists and their opponents. The proposed position includes a hypothesis on the function of the attitude of participation and the expressivist explications of the concepts crucial for the practice of ascribing moral responsibility. The important feature of the analyses in question is the central role of the states of mind whose content are plans for reactive moral sentiments.

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Authors and Affiliations

Adrian Kuźniar
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Abstract

The article presents Peter F. Strawson’s remarks on the free will debate, which he has presented in the essay ‘Freedom and Resentment’. Strawson avoids taking a stance on the question whether the thesis of determinism is correct. Instead he shows the essential difficulties and far reaching consequences of acknowledging this thesis. He recognizes the inseparable connection between freedom and responsibility in the philosophy after Kant. He consequently questions whether we really understand what it would mean to claim that determinism is true. He focuses on what he calls ‘reactiv attitudes’ triggered by the way in which other people behave toward us. Their behavior evokes emotional reaction in us – gratitude, respect, curiosity, but also distrust, resentment, disappointment. Those emotional responses are not purely subjective and they underlie moral judgments and complicated interpersonal relations. We suspend our reactive attitudes towards animals, very small children or people that we think are mentally ill. Instead we adopt objective (psychiatric, scientific) attitudes towards them. But to acknowledge the thesis of determinism implicates that we should treat all people this way. The paper is not so much concerned with an analysis of advantages and weak points of Strawson’s version of compatibilism, but focuses instead on the originality of his contribution to the debate on free will and on his brilliant treatment of reactive attitudes.

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Authors and Affiliations

Karolina Rychter
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Abstract

The paper is the second part of the work, devoted to a DC power supply with a power factor correction function. The power supply is equipped additionally with a shunt active power filter function, which enables the compensation of reactive and distortion power, generated by loads, connected to the same power grid node. A tunable inductive filter, included at the input of the power electronics current source – the main block of the power supply – allows for an improvement of the quality of the system control, compared to the device with a fixed inductive filter. This improvement was possible by extending the current source “frequency response”, which facilitated increasing the dynamics of current changes at the power supply input. The second part of the work briefly reminds the reader of the principle of operation and the structures of both the power supply control system and its power stage. The main purpose of this paper is to present the selected test results of the laboratory model of the electric system with the power supply.
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Bibliography

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Authors and Affiliations

Michał Gwóźdź
1
ORCID: ORCID
Rafał Wojciechowski
1
ORCID: ORCID
Łukasz Ciepliński
1
ORCID: ORCID

  1. Poznan University of Technology, Faculty of Control, Robotics and Electrical Engineering, Piotrowo 3A, 60-965 Poznan, Poland
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Abstract

The aim of this study was to measure serum neopterin and C-reactive protein (CRP) concen- trations in female dogs with mammary tumours and evaluate the association between the values of these indicators and some clinical characteristics of the tumour. Fifty three female dogs were used for this study, including 43 dogs with mammary gland tumours (10 benign and 33 malignant) and 10 healthy controls. The concentrations of neopterin and CRP were determined using the ELISA technique and commercial ELISA kits. The mean serum neopterin concentration in fe- male dogs with mammary tumours was lower than in healthy dogs, but significant difference was not found. Similarly, there were no significant differences in neopterin concentrations in female dogs based on tumour size, tumour ulceration and metastasis. The mean CRP concentration was significantly higher (p<0.05) in dogs with malignant tumours compared to dogs with benign tu- mours and control. Furthermore, serum CRP concentration was significantly higher (p<0.05) in dogs with metastatic malignant tumours compared to dogs with non-metastatic mammary tu- mours. The CRP concentration was significantly lower (p<0.05) in dogs with tumours less than 3 cm compared to those with larger tumours, and significantly higher in dogs with ulcerated tu- mours compared to those without ulceration. Our findings suggest that the neoplastic process in the mammary gland does not cause significant changes in serum neopterin concentrations in dogs. Higher concentrations of serum CRP in dogs with advanced stages of malignant tumours may suggest that CRP could be a potential prognostic marker in canine malignant mammary tu- mours, but this hypothesis needs further study.

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Authors and Affiliations

M. Szczubiał
R. Dabrowski
W. Łopuszyński
M. Bochniarz
M. Krawczyk
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Abstract

The work presents a DC power supply with power factor correction (PFC). This device is also equipped with a parallel active filter function, which enables the possibility of compensation (minimization) of reactive and distortion power, generated by a group of loads, connected to the same power grid node. A passive filter with variable inductance applied at the input of the power supply allows for a significant improvement in quality of the system control (given specific criteria), as compared to the solution with a filter with fixed parameters. This is possible by increasing the dynamics of current changes at the power supply input (extending its “frequency response”). The paper presents the principle of operation as well as structures and models of the power supply control system and its power stage. Selected test results of the simulation model of the electric system with the power supply, in various operating conditions, are also presented.

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Authors and Affiliations

M. Gwóźdź
Ł. Ciepliński
M. Krystkowiak
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Abstract

So far, numerous studies have been published on the selection of appropriate maintenance tactics based on some factors affecting them such as time, cost, and risk. This paper aims to develop the TRIZ contradiction matrix by explaining the dimensions and components of each of the following Reactive maintenance tactics. The related findings of previous studies were analyzed by adopting “Rousseau and Sandoski” seven-step method to identify and extract the relationships between TRIZ principles and Reactive maintenance tactics. Thereafter, 5 Reactive maintenance tactics were replaced TRIZ’s 40 principles in the TRIZ contradiction matrix. Finally, the ANP method were used to extract and prioritize the appropriate Reactive maintenance tactics. The proposed matrix in this research was used in the desalination section of one of the oil companies to select on the appropriate Reactive maintenance tactics. The results of this research is useful for managers and maintenance specialists of units in making decisions to provide appropriate Reactive maintenance tactics for the desired equipment.
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Authors and Affiliations

Mohammad Amin Mortazavi
1
Atefeh Amindoust
1
Arash Shahin
2
Mehdi Karbasian
3

  1. Department of Industrial Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
  2. Department of Management, University of Isfahan, Isfahan, Iran
  3. Department of Industrial Engineering, Malek-Ashtar University of Technology, Isfahan, Iran
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Abstract

Reactive powder concrete (RPC), due to its characteristic composition with reduced water quantity, often below a stoichiometric ratio, the addition of pozzolana usually close to or above 20% of the weight of cement and a significantly reduced inclusion rate compared to normal or high performance concrete, has a different nature of the interfacial transition zone between the micro aggregate grains and the binder matrix. Due to the significant influence of RPC curing conditions on the morphology of the interfacial transition zone, the analysis included composites cured in water of Tmax=20°C, subject to low-pressure steam curing Tmax=90°C and autoclaved at Tmax=250°C. The paper presents a qualitative assessment of the interfacial transition zone in reactive powder concretes with the use of a scanning microscope with the use of linear EDS and quantitative analysis by means of stereological analysis of the image obtained with the use of a BSE detector. The results of the study unequivocally confirm the lack of portlandite crystallisation at the phase interface and the different phase composition in the interfacial transition zone in relation to the mean mass composition.

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Authors and Affiliations

Tomasz Zdeb
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Abstract

Drug-abuse detection tests are becoming increasingly commonplace in patient care today and provide a rapid and effective method for identifying illicit substances. Occasionally, they may yield a positive result, indicating the presence of a substance, even though the individual has not consumed the suspected drug what sometimes can significantly impact both medical and legal decisions. The study outlines the substances that can lead to false-positive drug test results for amphetamines, cannabinoids, and benzodiazepines. The study’s findings have revealed pivotal insights for patients receiving chronic treatment and their primary care physicians. Notably, amphetamine assays appear to be most prone to cross-reactivity with other substances. The beta-blocker group of medications, confirmed by various studies to interfere with amphetamine assays, could pose a substantial challenge in drug screening given its widespread use. Efavirenz also warrants mention, as it frequently triggers positive results for both benzodiazepine and cannabinoid assays among its users. This research helps highlight new areas for further investigation and aims to guide clinicians in their daily practice, especially when interpreting questionable positive drug-abuse test results. This comprehensive review serves as a valuable resource for clinicians to navigate false-positive scenarios effectively and maintain the highest standard of patient care.
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Authors and Affiliations

Kamil Możdżeń
1
Konrad Kaleta
1
Agnieszka Murawska
1
Jakub Pośpiech
1
ORCID: ORCID
Piotr Panek
1
Barbara Lorkowska-Zawicka
2
Beata Bujak-Giżycka
2

  1. Student Scientific Group of Clinical Pharmacology, Jagiellonian University Medical College, Kraków, Poland
  2. Depatment of Clinical Pharmacology, Jagiellonian University Medical College, Kraków, Poland
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Abstract

In this study, solar cells based on copper oxide and titanium dioxide were successfully manufactured using the reactive direct-current magnetron sputtering (DC-MS) technique with similar process parameters. TiO2/CuO, TiO2/Cu2O/CuO/Cu2O, and TiO2/Cu2O solar cells were manufactured via this process. Values of efficiencies, short-circuit current, short-circuit current density, open-circuit voltage, and maximum power of PV devices were investigated in the range of 0.02÷0.9%, 75÷350 µA, 75÷350 µA/cm2, 16÷550 mV, and 0.6÷27 µW, respectively. The authors compare solar cells reaching the best and the worst conversion efficiency results. Thus, only the two selected solar cells were fully characterized using I-V characteristics, scanning electron microscopy, X-ray diffraction, ellipsometry, Hall effect measurements, and quantum efficiency. The best conversion efficiency of a solar cell presented in this work is about three times higher in comparison with the authors’ previous PV devices.
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Bibliography

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  27. Straumanis, M.  E. & Yu, L. S. Lattice parameters, densities, expansion coefficients and perfection of structure of Cu and Cu-In alpha phase. Acta Cryst. A25, 676–682 (1969). https://doi.org/10.1107/S0567739469001549
  28. Chrzanowska-Giżyńska, J. Cienkie warstwy z borków wolframu osadzane impulsem laserowym i metodą rozpylania magnetronowego –wpływ parametrów procesu na osadzone warstwy. (Instytut Podstawowych Problemów Techniki, Polska Akademia Nauk, Warszawa, 2017). [in Polish]
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  31. Hu, X. et al. Influence of oxygen pressure on the structural and electrical properties of CuO thin films prepared by pulsed laser deposition. Mater. Lett. 176, 282–284 (2016). https://doi.org/10.1016/j.matlet.2016.04.055
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Authors and Affiliations

Grzegorz Wisz
1
ORCID: ORCID
Paulina Sawicka-Chudy
1
ORCID: ORCID
Maciej Sibiński
2
ORCID: ORCID
Zbigniew Starowicz
3
ORCID: ORCID
Dariusz Płoch
1
ORCID: ORCID
Anna Góral
3
Mariusz Bester
1
ORCID: ORCID
Marian Cholewa
1
Janusz Woźny
4
ORCID: ORCID
Aleksandra Sosna-Głębska
2

  1. Institute of Physics, College of Natural Science, University of Rzeszów, 1 Pigonia St., 35-317 Rzeszów, Poland
  2. Department of Semiconductor and Optoelectronic Devices, Łódź University of Technology, 211/215 Wólczańska St., 90-924 Łódź, Poland
  3. Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Kraków, Poland
  4. Department of Semiconductor and Optoelectronic Devices, Łódź University of Technology, 211/215Wólczańska St., 90-924 Łódź, Poland
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Abstract

More and more street lighting deployments use LED technology as a light source. Unfortunately, the new technology also brings some challenges with it that remain unnoticed until installed at scale. This article presents issues related to capacitive reactive power consumed by LED luminaires. The problem is even more profound if the luminaire is dimmed, because it consumes capacitive reactive power, which is very undesirable in the power system. Countermeasures in terms of reactive power compensation for a luminaire working with variable power and their effects are also presented. The article also contains the results of the harmonic analysis of the LED luminaires current for full power and dimmed operation.
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Bibliography

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[7] Ł. Kosicki and D. Typańska, “Badanie odkształceń prądów i napięć generowanych przez oprawy z diodami LED,” Poznan university of technology academic journals, Electrical Engineering 2017, 92, 215-226.
[8] A. Djuretic, V. Skerovic, N. Arsic and M. Kostic, “Luminous flux to input power ratio, power factor and harmonics when dimming high-pressure sodium and LED luminaires used in road lighting,” Lighting Research & Technology, 2019. 51(2), 304–323. DOI: 10.1177/1477153518777272.
[9] A. Djuretic and M. Kostic, “Actual energy savings when replacing high-pressure sodium with LED luminaires in street lighting,” Energy 2018, vol. 157, pp. 367–378. DOI: 10.1016/j.energy.2018.05.179
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[11] F. A. Karim, M. Ramdhani and E. Kurniawan, "Low pass filter installation for reducing harmonic current emissions from LED lamps based on EMC standard," 2016 International Conference on Control, Electronics, Renewable Energy and Communications (ICCEREC), Bandung, 2016, pp. 132-135, DOI: 10.1109/ICCEREC.2016.7814966.
[12] L. S. Czarnecki, "Considerations on the Reactive Power in Nonsinusoidal Situations," in IEEE Transactions on Instrumentation and Measurement, vol. IM-34, no. 3, pp. 399-404, Sept. 1985, DOI: 10.1109/TIM.1985.4315358.
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Authors and Affiliations

Tomasz Lerch
1
ORCID: ORCID
Michał Rad
1
ORCID: ORCID
Igor Wojnicki
1

  1. AGH University of Science and Technology, Krakow, Poland
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Abstract

The results of a systematic study of the influence of meridional contours overlap in the stator-rotor axial interspace of the impulse and reactive type stages of a high-pressure steam turbine on the flow structure and gas-dynamic efficiency of the flow part are introduced. The studied flow parts of the impulse and reactive stages are typical for high-power high-pressure steam turbines. It is shown that the stages that have no overlaps and/or have a smooth shape of meridional contours have the best gasdynamic efficiency, and the most negative effect on the flow part is caused by the presence of caverns in the stator-rotor interspace. For cases where, due to technological limitations, it is impossible to avoid the presence of caverns and overlaps with a sharp (step-wise) change in the shape of the meridional contours, it is recommended to perform overlaps with positive size of overlap values near the rotor blades.
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Bibliography

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[4] Benner M.W., Sjolander S.A., Moustapha S.H.: Influence of leading-edge geometry on profile losses in turbines at off-design incidence: Experimental results and an improved correlation. J. Turbomach. 119(1997), 193–200.
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[11] Ainley D.G.; Mathieson C.R.: An Examination of the Flow and Pressure Losses in Blade Rows of Axial-Flow Turbines. Aeronaut. Res. Counc. Rep. Memo. Techn. Rep. 2891, London 1955.
[12] Osipov S.K.: Computational and experimental study of variants of the LP flow parts in order to increase their throughput. PhD thesis, National Research University Moscow Energy Institute, Moscow 2019.
[13] Baljé O.: Turbomachines – A Guide to Design, Selection and Theory. Wiley & Sons, New York 1981.
[14] Craig H.R.M., Cox H.J.A.: Performance estimation of axial flow turbines. P.I. Mech. Eng. 185(1970), 1, 407–424.
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[17] Scoretz M., Williams R.: Industrial Steam Turbine Value Packages. GE Energy, Atlanta 2008.
[18] Minchener A.: Developments in China’s coal-fired power sector. IEA Clean Coal Centre., London 2010,
[19] Rusanov A., Rusanov R., Lampart P.: Designing and updating the flow part of axial and radial-axial turbines through mathematical modelling. Open Eng. 5(2015), 399–410.
[20] Yershov S., Rusanov A., Gardzilewicz A., Lampart P.: Calculations of 3D viscous compressible turbomachinery flows. In: Proc. 2nd Symp. on Comp. Technologies for Fluid/Thermal/Chemical Systems with Industrial Applications. ASME PVP Division Conf., 1–5 August 1999, Boston, PVP, 397.2(1999), 143–154.
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[23] Lampart P., Rusanov A., Yershov S., Marcinkowski S., Gardzilewicz A.: Validation of 3D RANS Solver with a state equation of thermally perfect and calorically imperfect gas on a multi-stage low-pressure steam turbine flow. J. Fluid. Eng. – T ASME 127(2005), 83–93.
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Authors and Affiliations

Andrii Rusanov
1
Roman Rusanov
1

  1. The A. N. Pidgorny Institute of Mechanical Engineering Problems NAS of Ukraine, Dm. Pozharsky 2/10, 61046 Kharkiv, Ukraine
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Abstract

In this study defense responses in three potato varieties with different levels of reaction to the late blight disease caused by Phytophthora infestans were analyzed after inoculation with the pathogen. In the resistant cv. Pastusa Suprema, increased intensity of H2O2 and callose deposit accumulation was observed beginning at 24 hours after inoculation, followed by a hypersensitive response at the inoculation points. In the moderately resistant cv. Diacol-Monserrate, the same responses were observed as in the resistant variety, but with less intensity over time. For the susceptible cv. Diacol-Capiro, the responses observed occurred later than in the other two varieties, subsequent to the advance of the pathogen over extensive necrotic areas. These results suggest that early, intense peroxide and callose accumulation and a hypersensitive response are associated with the observed resistance of the cv. Pastusa Suprema and cv. Diacol-Monserrate to P. infestans.

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Authors and Affiliations

Astrid Elena Gaviria
Luis Fernando Patiño
Juan Gonzalo Morales
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Abstract

This paper presents the resolution of the optimal reactive power dispatch (ORPD) problem and the control of voltages in an electrical energy system by using a hybrid algorithm based on the particle swarmoptimization (PSO) method and interior point method (IPM). The IPM is based on the logarithmic barrier (LB-IPM) technique while respecting the non-linear equality and inequality constraints. The particle swarmoptimization-logarithmic barrier-interior point method (PSO-LB-IPM) is used to adjust the control variables, namely the reactive powers, the generator voltages and the load controllers of the transformers, in order to ensure convergence towards a better solution with the probability of reaching the global optimum. The proposed method was first tested and validated on a two-variable mathematical function using MATLAB as a calculation and execution tool, and then it is applied to the ORPD problem to minimize the total active losses in an electrical energy network. To validate the method a testwas carried out on the IEEE electrical energy network of 57 buses.

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Authors and Affiliations

Aissa Benchabira
Mounir Khiat
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Abstract

Grid-connected inverters are commonly used in systems of renewable energy to convert this energy source into AC power with parameters suitable for connection to the grid. In the normal operating conditions, the grid-connected inverters mainly generate active power to the grid. However, when a voltage sag or voltage imbalance occurs, the grid voltage imbalance in the conventional control methods causes negative sequence components and increases the output current magnitude of inverters. The increase of current can damage power semiconductor devices. This paper presents a strategy to limit the current magnitude of inverters under unbalanced grid voltage conditions. In this strategy, a multiple-complex-coefficient filter is used to eliminate the negative sequence voltage components. This method does not require any additional hardware. A three-phase gridconnected photovoltaic inverter system using a solar array of 20 kWp is also used for the survey. The effectiveness has been validated when comparing the simulation results on Matlab/Simulink of the proposed method with those of the conventional method.
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Authors and Affiliations

Tho Quang Tran
1
ORCID: ORCID

  1. Hochiminh City University of Technology and Education, Vietnam
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Abstract

Freedom and Resentment (1962) – reflecting the method and profoundness of descriptive metaphysics – has become perhaps the most commented and famous work by Peter F. Strawson. In this article I try to reconstruct the concept of responsibility, blame and punishment outlined in his essay. The text consists of three main parts: exhibition (subsections 2, 3), interpretation (4) and criticism (5). In the last part I argue that even if Strawson managed to repulse the pessimistic argumentation against compatibilism, his naturalistic position, as well as the traditional optimism, does not provide the right kind of ethical justification for reactive emotions and attitudes. The nerve of his reasoning is the premise that from the human point of view it is practically inconceivable to abandon them. Therefore, the succes of such argumentation depends on the meaning of practical inconceivability. One can distinguish its naturalistic (referring to the type- or token-naturalism) and transcendental interpretation. The latter, as I try to show, is unable to formally distinguish between the metaphysical and ethical content of Strawson’s position. On the other hand, the logical separation of both views is the main advantage of the interpretation in the spirit of type-naturalism. Consequently, its acceptance reveals both metaethical and anthropological allegations to which Strawson’s concept is exposed, without injuring the main part of his compatibilism.

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Authors and Affiliations

Stanisław Jędrczak
ORCID: ORCID
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Abstract

In the present study, the influence of the infection with equine herpesvirus type 1 (non-neuropathogenic and neuropathogenic strains of EHV-1) on the morphology and distribution of mitochondrial network in equine dermal cell line was investigated. Our results indicate that EHV-1-infection caused changes in the mitochondrial morphology manifested mostly by fission and reactive oxygen species generation.

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Authors and Affiliations

M. Bartak
M. Chodkowski
A. Słońska
M.W. Bańbura
J. Cymerys
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Abstract

Dehydroabietic acid R=COOH (DHA), a naturally occuring diterpene resin acid, is an activator of systemic acquired resistance (SAR) under biotic stress. However, there had been no report on its functioning under salinity. In the present study, we determined the effects of DHA on salinity and its possible role as a signal transmitter in soybean (Glycine max L.) leaves under salinity (200 mM NaCl). Furthermore, physiological parameters, chlorophyll, proline, malondialdehyde (MDA), hydrogen peroxide (H2O2) content, superoxide (O2‾) and hydroxyl radical (•OH) scavenge capacity, as well as antioxidant enzymes (SOD, POX, APX and GST) and GmWRKY-71 gene expressions were investigated in the treated plants at 6 h, 12 h and 24 h. The obtained results showed that pretreatment of DHA caused (1) a reduction in salt-induced damage, (2) improvement in biomass yield, water status, chlorophyll and leaf area, (3) regulation of the proline level and relative electrolyte leakage, (4) increase in reactive oxygen species (ROS) scavenging capacity, (5) induction of SOD and APX enzyme activity at all the investigated periods, while POX only at 6 h, and thus alleviation of the oxidative damage. In addition, the changes in GmWRKY-71 gene expressions were remarkable in soybean under salinity. To sum up, these results showed that DHA can be used as a ROS inhibitor or a signal molecule in increasing salt tolerance in soybean under salinity.

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Authors and Affiliations

Eda Tasci
Burcu Seckin Dinler
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Abstract

Introduction: Inflammatory bowel disease (IBD) represents a group of chronic inflamma-tory disorders characterized by dysbiosis and altered short-chain fatty acid (SCFA) level. The association between individual SCFA levels and cytokine levels is unknown.
Objectives: We aimed to determine the fecal SCFA levels in patients with IBD in relation to disease severity and the serum levels of pro- and anti-inflammatory cytokines.
Patients and Methods: The study included 61 patients with IBD (inactive, 22; active, 39) and 16 controls. Fecal levels of organic acids (acetic, lactic, propionic, butyric, isovaleric, isobutyric, and valeric), serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), IL-17, and IL-22, complete blood count and C-reactive protein (CRP) were measured.
Results: Patients with active IBD had reduced butyric, acetic, valeric, and isovaleric acid levels and elevated lactic acid levels in stool. Hemoglobin levels were positively correlated with the levels of acetic and butyric acids ( R = 0.266 and R = 0.346, respectively; P <0.05). In addition, CRP levels were inversely correlated with butyric acid levels ( R = –0.573; P <0.05). Higher serum TNF-α levels were observed in patients with active IBD compared with controls (6.64 pg/ml vs 2.05 pg/ml, P <0.05). No relationship was noted between the SCFA profile and cytokine levels.
Conclusions: The study showed that determination of SCFA levels can be used to evaluate the activity of IBD. The relationship between individual SCFA and cytokine levels seems to be complex and requires further studies.
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Authors and Affiliations

Olga Kaczmarczyk
1
Agnieszka Dąbek-Drobny
2
Michał Woźniakiewicz
3
Paweł Paśko
4
Justyna Dobrowolska-Iwanek
4
Aneta Woźniakiewicz
3
Aneta Targosz
5
Agata Ptak-Belowska
5
Agnieszka Piątek-Guziewicz
1
Kacper Wcisło
6
Paweł Zagrodzki
4
Małgorzata Zwolińska-Wcisło
1 2

  1. Department of Gastroenterology and Hepatology, Jagiellonian University Medical College, Kraków, Poland
  2. Unit of Clinical Dietetics, Department of Gastroenterology and Hepatology, Jagiellonian University Medical College, Kraków, Poland
  3. Department of Analytical Chemistry, Faculty of Chemistry, Jagiellonian University, Kraków, Poland
  4. Department of Food Chemistry and Nutrition, Jagiellonian University Medical College, Kraków, Poland
  5. Department of Physiology, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland
  6. Department of Pathomorphology, University Hospital, Kraków, Poland

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