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Number of results: 14
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Abstract

In this article, a monitoring system based on IoT technologies of the substation electrical system in the Republic of Kazakhstan was developed. At the moment, the operation of power systems is extremely important to maintain the frequency of electric current over time. For management and monitoring applications, it is necessary to take into account communication within acceptable limits. IoT technologies are considered the main functions in applications for monitoring and managing energy systems in real time, as well as making effective decisions on both technical and financial issues of the system, for monitoring the main form of data registration on an electric power substation in the city of Shymkent of the Republic of Kazakhstan, for consistent effective decision-making by system operators. In this work, an Internet of Things-based monitoring system was implemented and implemented for the substation of the power system using a specialized device built into the FPGA controller for fast integrated digitalization of transformer substations of real-time distribution electrical networks. The IoT platform also provides complete remote observability and will increase reliability for power system operators in real time. This article is mainly aimed at providing a practical application that has been implemented and tested.
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Authors and Affiliations

Maksat Kalimoldayev
1
Waldemar Wójcik
2
Zhazira Shermantayeva
1

  1. Institute ofInformation and Computing Technologies of the KN of the Ministry ofInternal Affairs of the Republic of Kazakhstan
  2. Lublin University of Technology, Lublin, Poland
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Abstract

The paper presents the results of hydrothermal zeolitization of fly ash from hard coal combustion in one of the Polish power plants. The synthesis was carried out using various NaOH fly ash mass ratio (3.0, 4.0 and 6.0) and the effect of NaOH concentration in the activating solution on composition of synthesized sample was tested. The process was carried out under the following permanent conditions temperature: 90°C, time – 16 hours, water solution of NaOH (L)/fly ash (g) ratio – 0.025. In the studied fly ash the dominant chemical components were SiO2 and Al2O3, while the main phase components were mullite, quartz and hematite, and a significant share of amorphous substance (glass and unburnt organic substance). After hydrothermal synthesis, the presence of unreacted fly ash phases was found in the products, as well as new phases, the quality and quantity of which depend on the NaOH to fly ash mass ratio used for synthesis:

 for ratio 3.0 – Na-LSX type zeolite and hielscherite,

 for ratio 4.0 – Na-LSX type zeolite, hielscherite and hydrosodalite,

 for ratio 6.0 – hydrosodalite and hielscherite.

The grains in all products of synthesis are poly-mineral. However, it was found that the new phases, overgrowing the unreacted phase components of fly ash, crystallize in a certain order. Hielscherite is the first crystallizing phase, on which the Na-LSX type zeolite crystallizes then, and the whole is covered by hydrosodalite. In the products of synthesis, the share of sodium-containing phases (the Na-LSX type zeolite and hydrosodalite) increases with the increasing concentration of NaOH in the solution used for the process.

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Authors and Affiliations

Zdzisław Adamczyk
ORCID: ORCID
Magdalena Cempa
ORCID: ORCID
Barbara Białecka
ORCID: ORCID
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Abstract

The problem of of the use of fly ash still constitutes a research and exploration area for scientists. This is due to the fact that, 6,000,000 Mg of coal combustion by-products (CCB) are storage on landfills yearly in Poland alone. One of the potential directions of using fly ash is to use it as a substrate in hydrothermal syntheses of mesoporous materials (synthetic zeolites). Zeolites are aluminosilicates with a spatial structure. Due to their specific structure they are characterized by a number of specific properties among others molecular-sieve, ion-exchange and catalytic that can be used in engineering and environmental protection. So far, the synthesis has been carried out using coal combustion by-products such as fly ash or microsphere. The article analyzes whether separation from the fly ash of the appropriate fraction (below 63 μm) will affect the formation of zeolite grains. The syntheses were carried out using class F fly ash and the fraction separated from it, which was obtained by sieving the ash through a 63 μm sieve. Chemical (XRF) and mineralogical (XRD, SEM-EDS) analyzes were carried out for substrates as well as the obtained reaction products. In the case of substrates, the analysis did not show any significant differences between the ash and the separated fraction. However, in products after synthesis (Na-X zeolite with a small amount of Na-P1 zeolite, and small amounts of quartz and unreacted aluminosilicate glass - mullite) higher aluminum and sodium contents were observed from the separated fraction, with a lower calcium and potassium content. A small proportion of illite was observed on the diffraction curve of the zeolite from the fraction. Observations of grain morphology showed no differences in formation. Based on the conducted analyzes, it can be stated that, considering the economics of the synthesis process, the separation of fine fractions from the fly ash does not affect the quality of the synthesis process.

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Authors and Affiliations

Dorota Czarna-Juszkiewicz
Piotr Kunecki
Rafał Panek
Magdalena Wdowin
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Abstract

Self-control is a complex and multifaceted construct that can be regarded as an individual trait that follows its own developmental trajectory. In the presented study we used NAS-50 for the assessment of self-control in adolescents and young adults. Since the questionnaire has not been used before in underage participants we tested its reliability in adolescent and adult samples. We also investigated possible age and gender differences in self-control abilities as well as relations between NAS-50 and behavioral measures of cognitive control and impulsivity. Although the sample was quite small, the reliability of the questionnaire was similar to the results achieved by its authors. According to the predictions in the literature we did not find relations between NAS-50 and behavioral measures of cognitive control and impulsivity. We also did not observe significant age differences in the assessment of self-control abilities. The theoretical relevance of our results is discussed.

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Authors and Affiliations

Joanna Fryt
Tomasz Smoleń
Karolina Czernecka
Keywords Mo2C MoO3 CO NaCl
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Abstract

In this work, influence of NaCl additive on the transformation process of MoO3 to Mo2C under pure CO atmosphere in the range of room temperature to 1170 K was investigated. The results showed that transformation of MoO3 to Mo2C can be roughly divided into two stages: the reduction of MoO3 to MoO2 (the first stage) and the carburization of MoO2 to Mo2C (the second stage). As to the first stage, it was found that increasing the content of NaCl (from 0 to 0.5 wt.%) was beneficial for the increase of reaction rate due to the nucleation effect; while when the content of NaCl increased to 2 wt.%, the reaction rate will be decreased in turn. As to the second stage, the results showed that reaction rate was decreased with the increase of NaCl, which may be due to the formation of low-melting point eutectic. The work also found that morphology of as-prepared Mo2C was irregular and particle size of it was gradually increased with increasing the NaCl content. According to the results, the possible reaction mechanism was proposed.
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Authors and Affiliations

Biao-Hua Que
1
ORCID: ORCID
Lu Wang
1 2
ORCID: ORCID
Bao Wang
3
ORCID: ORCID
Yi Chen
3
ORCID: ORCID
Zheng-Liang Xue
3
ORCID: ORCID

  1. Wuhan University of Science And Technology, Hubei Provincial Key Laboratory For New Processes of Ironmaking and Steelmaking, Wuhan 430081, China
  2. Foshan (Southern China) Institute For New Materials, Foshan 528200, Guangdong, China
  3. Wuhan University of Science and Technology, The State Key Laboratory of Refractories and Metallurgy, Wuhan 430081, China
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Abstract

Dolomite can be used as a source of aluminosilicate to produce geopolymers; however, this approach is limited by its low reactivity. This study analyzes the viability of producing geopolymers using dolomite/fly-ash with sodium silicate and NaOH solutions (at multiple concentrations) by determining the resultant geopolymers’ compressive strengths. The dolomite/fly-ash-based geopolymers at a NaOH concentration of ~22 M resulted in an optimum compressive strength of 46.38 MPa after being cured for 28 days, and the SEM and FTIR analyses confirmed the denser surface of the geopolymer matrix. The synchrotron micro-XRF analyses confirmed that the Ca concentration exceeded that of Si and Mg, leading to the formation of calcium silicate hydrate, which strengthens the resulting geopolymers.
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Authors and Affiliations

Emy Aizat Azimi
1
M.A.A. Mohd Salleh
1
Mohd Mustafa Al Bakri Abdullah
1
ORCID: ORCID
Ikmal Hakem A. Aziz
1
ORCID: ORCID
Kamarudin Hussin
1
ORCID: ORCID
Jitrin Chaiprapa
2
ORCID: ORCID
Petrica Vizureanu
3
ORCID: ORCID
Sorachon Yoriya
4
ORCID: ORCID
Marcin Nabiałek
5
ORCID: ORCID
Jerzy J. Wyslocki
5
ORCID: ORCID

  1. Universiti Malaysia Perlis (Unimap), Centre of Excellence Geopolymer and Green Technology (CeGeoGTech), Perlis, Malaysia
  2. Synchrotron Light Research Institute (SLRI), 111 University Avenue, Muang District, Nakhon Ratchasima 30000, Thailand
  3. ”Gheorghe Asachi” Technical University, Faculty of Materials Science and Engineering, Blvd. D. Mangeron 71, 700050 Lasi, Romania
  4. National Metal and Materials Technology Center (MTEC), 114 Thailand Science Park, Phaholyothin Road, Klong 1, Klongluang, Pathumthani 12120, Thailand
  5. Czestochowa University of Technology, Department of Physics, 42-200, Czestochowa, Poland
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Abstract

Geopolymer is synthesized by polycondensation of SiO4 and AlO4 aluminosilicate complexes, tetrahedral frames linked with shared sialate oxygen. This paper studies the effect of the solids-to-fluids (S/L) and Na2SiO3/NaOH proportions on the preparing of metakaolin inorganic membrane geopolymer. By consolidating a mixture of metakaolin with sodium hydroxide, sodium silicate and foaming agent, the geopolymer membrane was made in required shape about 1 cm and cured at 80°C for 24 hours. After the curing process, the properties of the samples were tested on days 7. Sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) solution were utilized as an alkaline activator with a NaOH fixation fixed at 10 M. The geopolymer inorganic membrane tests were set up with various S/L proportions (0.8, 1.0, 1.2 and 1.4) and Na2SiO3/NaOH proportions (0.5, 1.0, 1.5, 2.0 and 2.5). Aluminium (Al) powder as a foaming agent was used to create bubbles in porous structure and provide details on the development of membrane geopolymers. This metakaolin membrane, based on the geopolymer, was synthesized by a suspension that depends on the fast cementing mechanism of high-temperature slurries. Porous geopolymeric circles provided a homogeneous composition and quantitative distribution of pores. The water absorption, density, impact toughness testing and microstructure analyses were studied. However, considering the promising results, an adjustment in the mix design of the metakaolin inorganic membrane geopolymer mixtures could increase their mechanical properties without negatively affecting the mechanical properties and porosity, making these sustainable materials a suitable alternative to traditional porous cement concrete.
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Authors and Affiliations

Masdiyana Ibrahim
1 2
ORCID: ORCID
Wan Mastura Wan Ibrahim
2 3
ORCID: ORCID
Mohd Mustafa Al Bakri Abdullah
1 2
ORCID: ORCID
Ahmad Syauqi Sauffi
1 2
ORCID: ORCID
Petrica Vizureanu
4
ORCID: ORCID

  1. Universiti Malaysia Perlis (UniMAP), Faculty of Chemical Engineering Technology, 02100, Padang Besar, Perlis, Malaysia
  2. Universiti Malaysia Perlis (UniMAP), Center of Excellence Geopolymer & Green Technology (CeGeoGTech), 02600, Arau, Perlis, Malaysia
  3. Universiti Malaysia Perlis (UniMAP), Faculty of Mechanical Engineering Technology, 02600, Arau, Perlis, Malaysia
  4. Gheorghe Asachi Technical University of Iasi, Faculty of Materials Science and Engineering, 700050, Iasi, Romania
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Abstract

Natural disasters have an effect on many important economic and social parameters and are related to a wide spectrum of sciences. Their kind, form, scale, intensity and other characteristics vary in different areas on Earth. One of the most common fields where such disasters are of great importance (either as threats or as resulting damage) is the urban environment (either the buildings or the infrastructure). The complexity of the natural disasters concerning each of the five phases in their lifecycle (prevention, mitigation, preparedness, emergency management, recovery) leads to the selection of strong and most capable tools, in order to predict their results, i.e. the damage. Since nowadays the geospatial technologies have undergone an effective shift to become better suited to the internet, the most appropriate tools for this purpose are the Web-based GIS. In this review paper, a Web-based GIS, which is under development, named SyNaRMa (Information System for Natural Risk Management in the Mediterranean) is being presented. SyNaRMa features include collection and analysis of data related to earthquakes, landslides and forest fires, simulation of natural disaster effects resulting from realistic scenarios and prediction of their impact on the natural and anthropogenic environment of the wider implementation areas. It is to be noted that its open architecture offers many benefits and conveniences for future plans as for example the incorporation within the system of data related to other natural disasters (e.g. drought, desertification, tsunamis, volcanic eruptions etc.) and the potential to be used all over the world.
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Authors and Affiliations

Ioannis D. Doukas
Paraskevas Savvaidis
Ilias N. Tziavos
Vassilios N. Grigoriadis
Ioanna Papadopoulou
Ioannis Vavassis
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Abstract

A new extraction process suitable for treating refractory CuCo2S4 under atmospheric pressure acidic leaching conditions was investigated. The effect of variables such as oxidant species, liquid-to-solid ratio, leaching time, oxidizing agent and mineral quality ratio, H2SO4 concentration, temperature and sodium chloride concentration on the extraction efficiency of Co, Cu and Fe from CuCo2S4 were investigated. Under optimal conditions including P80-P90 of the sample was d < 0.0074 mm, stirring speed of 400 rpm, leaching time of 8 h with sodium chlorate (NaClO3) and mineral quality ratio of 0.5, 2 mol/L H2SO4, liquid-to-solid ratio of 7, leaching temperature of 90°C and 4 mol/L sodium chloride. The leaching efficiency of Co, Cu, and Fe were nearly 97.08%, 100%, and 92.45%, respectively. Furthermore, the contents of cobalt and copper in leaching residue were all less than 0.4 wt.%, which satisfies the requirements of industrial production.

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Authors and Affiliations

Bo Dong
Jian-Hui Wu
Jun Wu
ORCID: ORCID
Xian-Peng Zhang
Jing-Jun Zhai
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Abstract

This study focused on the fatigue and corrosion fatigue of maraging steel 18Ni (250). The 18Ni (250) samples were tested for axial fatigue in air and 3.5% NaCl solution. The effects of loading frequency and stress ratio on the fatigue strength of 18Ni (250) were studied. In air, the loading frequency was 10 Hz, and the stress ratio was 0.5. However, three loading methods were used in the 3.5% NaCl solution: (i) the loading frequency of 1 Hz and stress ratio of 0.5; (ii) the loading frequency of 1 Hz and stress ratio 0.1, and (iii) the loading frequency 5 Hz and stress ratio 0.5. The corrosion fatigue strength of samples in the 3.5% NaCl solution was 63.3% lower than that of the samples in air. The fractures in the samples were observed after the test.
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Authors and Affiliations

Zhu Yongmei
1
Chen Junjie
1
Tang Wenxian
1
Cui Weicheng
2 3
Wang Xiaorong
1
Wang Fang
2
Yin Baoji
1

  1. Jiangsu University of Science and Technology, College of Mechanical Engineering, Zhenjiang 212003, China
  2. College of Engineering Science and Technology, Shanghai Ocean University, Shanghai 201306, China
  3. Westlake University, School of Engineering, Hangzhou 310024, China
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Abstract

This study focused on the fatigue and corrosion fatigue of maraging steel 18Ni (250). The 18Ni (250) samples were tested for axial fatigue in air and 3.5% NaCl solution. The effects of loading frequency and stress ratio on the fatigue strength of 18Ni (250) were studied. In air, the loading frequency was 10 Hz, and the stress ratio was 0.5. However, three loading methods were used in the 3.5% NaCl solution: (i) the loading frequency of 1 Hz and stress ratio of 0.5; (ii) the loading frequency of 1 Hz and stress ratio 0.1, and (iii) the loading frequency 5 Hz and stress ratio 0.5. The corrosion fatigue strength of samples in the 3.5% NaCl solution was 63.3% lower than that of the samples in air. The fractures in the samples were observed after the test.

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Authors and Affiliations

Zhu Yongmei
Chen Junjie
Tang Wenxian
Cui Weicheng
Wang Xiaorong
Wang Fang
Yin Baoji
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Abstract

The article discusses little-known facts from the lives of two great representatives of the Silver Age of Russian philosophy – Nikolai Berdyaev and Sergei Bulgakov – referring to the period when both were ardent Marxists. It discusses the beginning of the academic career of both thinkers, the turn of the 19th and 20th centuries. In the archives of Karl and Luise Kautsky in Amsterdam (International Institute of Social History) there are two Berdyaev’s letters to Kautsky regarding polemics about Marx and Marxism, which unfolded between them after Kautsky’s decision to publish in the pages of Die Neue Zeit an article by Berdyaev “F.A. Lange and Critical Philosophy in Its Relation to Socialism” (1900). This correspondence has probably become the catalyst for Berdyaev’s transition from ‛orthodox’ to ‛critical’ Marxism. On the other hand, Bulgakov’s letters to Kautsky (and those of his wife, Helena Tokmakova, to Luisa Kautsky) refer to the time of a research internship of Bulgakov in Berlin in the years 1898–1900. He then met Kautsky and Bernstein families, and engulfed himself in theoretical problems of Marxism. The text of the speech is accompanied by a translation into Polish and provided with comments on two Berdyaev’s letters to Kautsky (February and May 1900).

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Authors and Affiliations

Lilianna Kiejzik
ORCID: ORCID
Bogumiła Husak
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Abstract

The study analyzes the Ruthenian language of a remarkable bilingual print that appeared in the important Orthodox cultural center Ostrih in Church Slavonic and in Ruthenian “prosta mova” (“common language”) in 1607. It offers a critical evaluation of earlier studies and adds several new observations and theses.

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Authors and Affiliations

Michael Moser
ORCID: ORCID
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Abstract

The study analyzes the vocabulary of the Ruthenian “prosta mova” (“common language”) in a bilingual Ruthenian-Church Slavonic printed edition of 1607 (“Likarstvo na ospalyj umysl´´ čolovičyj” – “A Remedy for the Idle Human Mind”, translated by Demian Nalyvajko). We single out and discuss those lexical stems of the Ruthenian text that have no immediate equivalent in the early modern Polish language. Some of these stems belong to the Orthodox church terminology, others can be explained by the Church Slavonic original of the translation, still others demonstrate that Nalyvajko, like many other Ruthenian authors of that period, avoided certain Polish word stems despite the fact that his language is characterized by a plethora of marked Polonisms, and some of these avoided stems do occur in other Ruthenian texts of that period. Several markedly Ruthenian stems belong to the sphere of functional words.

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Authors and Affiliations

Michael Moser
ORCID: ORCID

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