Nowe zasoby w kolekcji Artykuły http://suw.biblos.pk.edu.pl/ Biblioteka Politechniki Krakowskiej lipinska@biblos.pk.edu.pl 60 <![CDATA[Study of increasing thermodynamic efficiency and hydrogen amount in the process of solid fuels and biomass gasification]]> Wed, 18 May 2022 14:45:33 +0200 Mitianiec, Władysław
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Abstrakt: The effect of fuel composition such as hard coal and biomass in fluidized bed on the thermodynamic efficiency of three gasifier types, low heating value (LHV) and syngas composition was studied by simulation in CFD program. The paper presents various small gasification systems with fluidized bed of water-coal mixture and water-biomass mixture both with oxygen (air) and without oxygen. The work presents the extended mathematical model of gasification process taking into account also 13 kinetic chemical reactions enabled to apply them in CFD program. The chemical model is based on surface reactions given in the model of Equivalent Reactor Network (ERN) in Ansys Energetico. Simulation of gasification of different reactor designs enabled to obtain the mass concentration of chemical compounds in the syngas which influenced on thermodynamic efficiency and LHV. Additionally, heating of the gasifier walls by electrical system without air gives higher mass ratio of hydrogen (15%) and carbon monoxide (75%) in the syngas than in the oxidized gasification system. The simulation tests showed high thermodynamic efficiency, taking into account the exergy above 80%, both for the oxygen gasification of hard coal-slurry and biomass as well as for the externally heated gasifier without the supply of oxygen. The highest thermodynamic efficiency was obtained during gasification of energy willow in the oxidation reactor due to the large difference in LHV of syngas and fuel. Obtaining the maximum possible mass ratio of H2 in syngas and a high thermal efficiency for the OXGR system from the gasification of subbituminous coal dust occurs at a ratio C/O2 = 0.314 and at almost stoichiometric ratio of C/H2O=0.63. In the case of gasification of biomass in the form of finely ground energy willow in the OXGR system, these ratios were respectively: O2/C=1.82 and C/H2O=0.47. While maintaining the almost stoichiometric ratio C/H2O = 0.75, resulting from the water-gas shift reaction, low heating value of the syngas for the analysed gasification systems was over 25 MJ/kg. The paper shows comparison of mass fractions of CO, H2, H2O, H2S, CO2, O2, CH4, tar and other chemical compounds in the syngas. Application of the gasification reactor with external heated walls and without oxygen inflow produces the syngas without tar and volatile species in comparison to the systems with additional oxygen supply. In oxidized reactors the syngas contains a large amount of CO2 about 25 – 30% of total mass.]]>
<![CDATA[The mechanical and tribological properties of epoxy-based composites filled with manganese-containing waste]]> Wed, 18 May 2022 13:50:48 +0200 Sławski, Sebastian; Woźniak, Anna; Bazan, Patrycja; Mrówka, Maciej
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Abstrakt: Waste from large-scale production processes is a growing environmental problem that can potentially be solved by using this waste as fillers in polymeric composites to improve the mechanical and tribological properties of polymeric matrixes. This paper presents research concerning how the introduction of fillers in the form of manganese residue and manganese(II) oxide changes the mechanical and tribological properties of epoxy composites produced by gravity casting. The research was carried out for composites with 2.5 wt.%, 5 wt.%, and 10 wt.% of fillers. Properties such as the density, hardness, resilience, flexural strength, deflection, flexural modulus, tensile strength, elongation at break, and Young’s modulus were determined. Moreover, based on the ball-on-plate test, the wear volume and friction coefficients of the tested materials were determined. Microscopic images of the abrasion profiles were also obtained. The geometry of the wear paths was measured with a profilometer, and the results showed that introducing fillers reduced the abrasive wear of the composites; however, in all cases, the fillers decreased the strength of the tested materials.]]>
<![CDATA[The synthesis methodology and characterization of nanogold-coated Fe3O4 magnetic nanoparticles]]> Wed, 18 May 2022 13:45:30 +0200 Kędzierska, Magdalena; Drabczyk, Anna; Jamroży, Mateusz; Kudłacik-Kramarczyk, Sonia; Głąb, Magdalena; Tyliszczak, Bożena; Bańkosz, Wojciech; Potemski, Piotr
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Abstrakt: Core-shell nanostructures are widely used in many fields, including medicine and the related areas. An example of such structures are nanogold-shelled Fe3O4 magnetic nanoparticles. Systems consisting of a magnetic core and a shell made from nanogold show unique optical and magnetic properties. Thus, it is essential to develop the methodology of their preparation. Here, we report the synthesis methodology of Fe3O4@Au developed so as to limit their agglomeration and increase their stability. For this purpose, the impact of the reaction environment was verified. The properties of the particles were characterized via UV-Vis spectrophotometry, dynamic light scattering (DLS), X-ray diffraction (XRD), and Scanning Electron Microscopy-Energy Dispersive X-ray analysis (SEM-EDS technique). Moreover, biological investigations, including determining the cytotoxicity of the particles towards murine fibroblasts and the pro-inflammatory activity were also performed. It was demonstrated that the application of an oil and water reaction environment leads to the preparation of the particles with lower polydispersity, whose agglomerates’ disintegration is 24 times faster than the disintegration of nanoparticle agglomerates formed as a result of the reaction performed in a water environment. Importantly, developed Fe3O4@Au nanoparticles showed no pro-inflammatory activity regardless of their concentration and the reaction environment applied during their synthesis and the viability of cell lines incubated for 24 h with the particle suspensions was at least 92.88%. Thus, the developed synthesis methodology of the particles as well as performed investigations confirmed a great application potential of developed materials for biomedical purposes. ]]>
<![CDATA[Problem wypalenia zawodowego wśród bibliotekarzy szkół wyższych w Polsce]]> Wed, 18 May 2022 12:29:56 +0200 Donnersberg, Anna
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Abstrakt: Artykuł porusza problematykę zjawiska wypalenia zawodowego wśród bibliotekarzy. Sporządzono ogólny zarys teorii oraz przedstawiono wyniki badania ankietowego przeprowadzonego w środowisku akademickim. Zwrócono uwagę na przyczyny występowania syndromu wypalenia zawodowego, jego przejawy oraz ewentualne konsekwencje.]]>
<![CDATA[Sustainable systems for the production of district heating using meat-bone meal as biofuel: a Polish case study]]> Wed, 18 May 2022 07:37:28 +0200 Kowalski, Zygmunt; Makara, Agnieszka
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Abstrakt: The developed production of heat (steam) by Farmutil Company enables use of renewable energy from biofuel meat-bone meal which is incinerated in rotary kilns utilising vapours and odours from its production, instead of natural gas, to ensure Farmutil’s own needs for heat. The transformation of existing district heating in Piła city (currently using coal) into a fourth generation district heating system was proposed, predicting the use of heat (hot water) after combustion of biofuel meat-bone meal as district heating in the city of Piła. The maximum possible surplus amount of heat that can be produced at Farmutil exceeds the needs for the district heating demands of the city of Piła (860,200 GJ/y) by 53.2% at a meat-bone meal burning scale of 150,000 t/y. The use of 52,000 t/y of meat-bone meal for district heating production also results in an increase in incomes through the sale of hydroxyapatite ash from its combustion, amounting 1.638 million EUR/y. The closure of the coal-fired heating plant eliminates the consumption of 44,000 t/y of coal and the need to pay CO2 emission permits amount to over 5.588 million EUR/y.]]>
<![CDATA[Determining the effectiveness of street cleaning with the use of decision analysis and research on the reduction in chloride in waste]]> Wed, 18 May 2022 07:34:20 +0200 Gronba-Chyła, Anna; Generowicz, Agnieszka; Kwaśnicki, Paweł; Cycoń, Dawid; Kwaśny, Justyna; Grąz, Katarzyna; Gaska, Krzysztof; Ciuła, Józef
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Abstrakt: Waste from street cleaning is usually of a fine fraction below 10 mm and varies greatly in both quantity and composition. It may be composed of chlorides, especially for that resulting during winter due to the use of street de-icing agents. Chlorides can cause the salinization of surface water and groundwater, and the salinization of soils, which in turn lead to the deterioration of water purity and a decrease in biodiversity of aquatic organisms, changes in microbiological structure, and increases in toxicity of metals. Therefore, it is very important to determine the level of salinity in stored waste and its impact on the environment. The present study was conducted in a city of about 55,000 inhabitants. The highest chloride concentrations were observed after winter in waste from street and sidewalk cleaning around the sewer gullies, amounting to 1468 mg/dm3 . The lowest chloride concentration in this waste occurred in summer and amounted to 35 mg/dm3 . The multicriteria analysis indicated that the most beneficial form of street cleaning and, thus, of reductions in chloride concentration in the waste from street cleaning, would be sweeping and daily washing. The objective of this research was to determine the amount of chlorides in sweepings on an annual basis in order to determine the potential risks associated with their impact on select aspects of the environment and to evaluate the frequency of necessary cleaning for city streets, considering the effects. The methodology used was a multi-criteria evaluation, which as a decision analysis, allowed us to determine the frequency of cleaning and washing of streets, in such a way that an ecological effect is achieved with simultaneous economic efficiency.]]>
<![CDATA[Czarny Dunajec: selected issues of cultural heritage conservation]]> Wed, 18 May 2022 07:30:56 +0200 Kuśnierz, Kazimierz; Bednarz, Łukasz; Mamedov, Alirza; Malczewska, Joanna
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Abstrakt: This paper presents the cultural heritage of the former town of Czarny Dunajec in the context of protecting urban design and architectural monuments. Czarny Dunajec is located in Nowy Targ Powiat, in Lesser Poland Voivodeship. At present, is the seat of a rural municipality. In the past it used to be one of the most important townships in the Podhale region, and owed its significance to its favorable location along supralocal and local trade routes. This paper discusses the history of Czarny Dunajec, its urban layout and historical buildings. It traces the development of the town’s spatial development based on historical documents and cartographic materials, including royal inspection reports and nineteenth-century Austro-Hungarian military survey maps by Friedrich von Mieg, outlining events that may have impacted it the most. Attention was drawn to the need for the statutory protection of the town’s most valuable monuments, which include its urban layout, a synagogue, and selected traditional houses which have still survived in the village, albeit mostly vestigially.]]>
<![CDATA[Genesis and functional features of Chinese pavilions and Chinese experience in the restoration of wooden structures]]> Wed, 18 May 2022 07:27:13 +0200 Ivashko, Yulia; Peng, Chang; Yang, Ding; Krupa, Michał; Bednarz, Łukasz
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Abstrakt: This paper presents a study on the specific features of traditional Chinese pavilions. The sources investigated during the study expanded the authors’ outlook on the expression of national characteristics in Chinese architecture as a whole, and became the basis for concluding that the pavilion can act as a vehicle for national identity. In their study, the authors focused solely on researching the architecture of small Chinese pavilions. It was concluded that the architecture of pavilions should be considered together with the general principles of Chinese philosophy, culture, religions, landscape design, the architecture of purely garden pavilions – as together with pavilions with other uses and it allows us to identify similarities and differences between pavilions of various types. Based on the transfer of information from the fundamental sources to specific layouts and landscape paintings of Suzhou gardens in this study, those landscape techniques that were formed based on Feng Shui and their symbolic meaning were concretized in the conclusions. The discussion focuses on the repair, renovation and reinforcement of timber structures susceptible to the effects of aggressive external factors (rainfall, insects, technical wood pests, fire) using methods acceptable in conservation.]]>
<![CDATA[Tadeusz Bierczyński - Pamiętnik Legionisty 1914–1915]]> Wed, 18 May 2022 07:18:37 +0200 Follprecht, Kamila; Gaczoł, Andrzej
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Abstrakt: Tadeusz Bierczyński (1891–1970), absolwent prawa UJ, dowodził oddziałem „Sokoła”, który wyruszył z Wieliczki 25 sierpnia 1914 r. do tworzących się w Krakowie Legionów. Służył w 2. Pułku Piechoty, uczestniczył w zimowej ofensywie II Brygady, brał udział w najcięższych bitwach na Bukowinie: pod Kirlibabą (17–21 stycznia 1915 r.) oraz Korolówką (6–7 marca 1915 r.). Podczas walk zapisywał wydarzenia z życia legionisty, jednak zachowały się tylko fragmenty maszynopisu tekstu dziennika, obejmujące wydarzenia od 25 sierpnia do 21 października 1914 r., następnie od 10 stycznia do 9 marca 1915 r. oraz od 11 do 31 maja 1915 r. Zawierają interesujące informacje nie tylko o przebiegu działań wojennych, ale o życiu codziennym legionistów, spojrzenie na organizację działań wojskowych, wiadomości o legionistach czy opisy miejsc, w których oddziały stacjonowały.]]>
<![CDATA[Scale-up and testing of polyurethane bio-foams as potential cryogenic insulation materials]]> Wed, 18 May 2022 07:08:29 +0200 Kurańska, Maria; Cabulis, Ugis; Prociak, Aleksander; Polaczek, Krzysztof; Uram, Katarzyna; Kirpluks, Mikelis
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Abstrakt: This article compares the properties of closed-cell PUR bio-foams produced on a laboratory scale and on an industrial scale. In the formulation used, the polyol premix contained 40 wt.% of a bio-polyol based on rapeseed oil. Selected useful properties of the foams obtained on the two scales and the use of one-step and spraying methods were compared. In the case of the spraying method, the experimental system was compared to a commercial one. Given the possibility of applying the bio-foams in insulation systems for cryogenic and liquefied natural gas (LNG) applications, a compressive strength analysis of the foams was carried out at room temperature as well as at −196 ◦C. It was found that the foams modified with the bio-polyol were characterized by a higher compressive strength at low temperatures than commercial foams based on a petrochemical polyol.]]>
<![CDATA[Physical, mechanical properties and durability of cement mortars containing fly ash from the sewage sludge incineration process]]> Tue, 17 May 2022 14:29:01 +0200 Zdeb, Tomasz; Tracz, Tomasz; Adamczyk, Marcin
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Abstrakt: Pursuant to European Union regulations, waste generated during municipal sewage treatment should be managed in an environmentally friendly manner. In order to eliminate the risk to human health and to the environment, and also to minimise the volume of the resulting sludge, it is subjected to thermal treatment. The resulting ash contains heavy metals, and thus proper management is required. Since it is known that products of cement hydration reactions have a potential ability to immobilise heavy metals, a preliminary verification was conducted of the possibility of disposing of this type of waste by including it in cement composites. For this purpose, suitable tests were carried out on the mechanical properties and durability of cement binders containing ash from the incineration of sludge produced from municipal sewage (Sewage Sludge Ash – SSA). The tests were conducted for a standard mortar composition based on Portland cement CEM I and on ash obtained on a technical scale in a sewage treatment plant at a temperature of about 850 ◦C. This mineral addition was used to replace 10%, 20%, 30% and 40% of the cement by weight. The physical and mechanical characteristics were measured, such as compressive and flexural tensile strength after 14, 28 and 90 days of curing as well as durability characteristics such as total porosity, the ability to transport chloride ions and resistance to sulphate ions. The results obtained confirm that replacing 10% of the cement with this admixture has a beneficial effect on the mechanical and durability characteristics, but greater amounts are reflected in a clear deterioration of these characteristics.]]>
<![CDATA[Cement with fly ash and metakaolin blend – drive towards a more sustainable construction]]> Tue, 17 May 2022 13:48:51 +0200 Dvorkin, Leonid; Zhitkovsky, Vadim; Sitarz, Mateusz; Hager, Izabela
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Abstrakt: This article presents experimental studies that have shown the effectiveness of using a composition of fly ash and metakaolin as an active mineral admixture to cement. It is shown that composite ash–metakaolin additives (AMAd) have on the one hand increased pozzolanic activity and surface energy, and, on the other hand, moderated water demand and provided a significant increase in strength, which is especially important for low-cement concretes. The obtained experimental–statistical models make it possible to determine the effect of the AMAd composition, it's content in combination with the addition of a superplasticizer on the rheological properties, the kinetics of structure formation and the main physical and mechanical properties of cement.]]>
<![CDATA[A new approach to the determination of silicon in zinc, lead-bearing materials and in waste using the ICP-OES method]]> Tue, 17 May 2022 13:46:01 +0200 Przybyła, Artur; Kuc, Joanna; Wzorek, Zbigniew
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Abstrakt: This work describes the implementation of the ICP-OES silicon determination method for zinc and lead-bearing materials and waste at the Mining and Metallurgical Works ZGH "Bolesław". The proposed method was validated. On the basis of linearity tests, it was found that the course of the calibration curve is linear up to a silicon concentration of 100 mg/L, with the determined working range being 0.10–50%. Precision tests, on the basis of which the repeatability was checked, were carried out for nine types of real samples: zinc sulfides, zinc oxides, zinc-lead ore, lead sulfide and zinc-bearing waste. Real samples and six certified reference materials were tested using the ICP-OES radial position. The identified interferences of molybdenum, chromium and vanadium did not statistically significantly affect the measurement results.]]>
<![CDATA[Let us not forget the victims of COVID-19 pandemics who did not die with the coronavirus]]> Tue, 17 May 2022 12:40:56 +0200 Pashkevich, Anton; Burghardt, Tomasz E.
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<![CDATA[Silver and copper modified zeolite imidazole frameworks as sustainable methane storage systems]]> Mon, 16 May 2022 13:55:56 +0200 Jodłowski, Przemysław J.; Kurowski, Grzegorz; Skoczylas, Norbert; Pajdak, Anna; Kudasik, Mateusz; Jędrzejczyk, Roman J.; Kuterasiński, Łukasz; Jeleń, Piotr; Sitarz, Maciej; Li, Ang; Mazur, Michal
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Abstrakt: The effective sorption of methane with mesoporous adsorbents is one of the most sought-after methods of energy storage. The constant development of organometallic networks and the synthesis of new materials increases the efficiency of methane sorption, reaching new record amounts of gas adsorbed per gram of adsorbent. In this study, we present the optimised in-situ synthesis preparation method of Ag and Cu-modified zeolite imidazole frameworks by using ultrasonic irradiation. We proved that silver is present in ZIFs in the form of nanoparticles in the case of silver-modified materials. In contrast, in the case of copper-modified materials, the copper is present in ionic form. We also found that incorporating PVP as a stabilising agent and the modification with Ag and Cu changes the structural parameters of the prepared materials. The methane sorption results confirmed that the developed materials exhibit enhanced sorption capacity by over 100% (based on ZIF-8) and by 20% (based on ZIF-67). The highest methane adsorption at 1.6 MPa was achieved by Cu-PVP/ZIF-8 and Cu-PVP/ZIF-67, and Ag-PVP@ZIF-67 samples, and was equal to 112 cm3 CH4/g, 96 cm3 CH4/g and 97 cm3 CH4/g, respectively. The developed sonochemically assisted synthesis method allowed to obtain Ag and Cu modified zeolite imidazole frameworks which may be considered as efficient materials for sustainable methane storage systems.]]>
<![CDATA[Spectroscopic and microscopic studies of Co, Ce, and Pd containing gamma-alumina as catalysts for cyclohexene oxidation]]> Mon, 16 May 2022 13:14:18 +0200 Kuterasiński, Ł.; Kurowski, G.; Jeleń, P.; Sitarz, M.; Jodłowski, P. J.
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Abstrakt: The oxidation of cyclohexene belongs to the most important reactions in organic chemistry and leads to the production of the precursors for surfactants, polymers, agrochemicals, and drugs. So far, however, due to a complex reaction mechanism, it was hard to find the catalyst of satisfactory properties. Attractive catalysts in this reaction could be sonochemically prepared Co, Ce, and Pd containing γ-Al2O3, which is the object of the undertaken research. What is more, this combination of metals in the oxide system has not been studied. The analysis of catalytic performance indicated that all studied catalysts were active in the catalytic oxidation of cyclohexene. For metal-containing alumina (Me=Co, Ce, Pd), the conversion of cyclohexene was 61–84%. The best catalyst was Co5Ce5/γ-Al2O3 s, prepared via the sonochemically-assisted procedure. It was also shown that the application of ultrasonic irradiation during the preparation of samples enhanced metal distribution over alumina support, resulted in smaller crystallites of prepared materials, and caused higher surface area with simultaneous smaller both pore size and pore volume in comparison with counterparts prepared via the standard procedure. XRD, Ra, and DR.-UV–vis spectroscopies indicated the coexistence of Co as Co3O4 and CoAl2O4 spinel, however, Ce was found in the form of CeO2. The addition of Pd to Co/γ-Al2O3 did not influence the status of cobalt.]]>
<![CDATA[A multi‐criteria evaluation of applications supporting public transport users]]> Mon, 16 May 2022 13:11:31 +0200 Solecka, Katarzyna; Kiciński, Marcin
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Abstrakt: Reducing the energy consumption of transport in urban areas is possible if appropriate measures are taken to make public transport more attractive. These include all kinds of journey planners that are part of the passenger information system. Various applications available on the market allow passengers to evaluate their usability. This paper presents and compares nine of the most popular journey planners available to iOS and Android users travelling in Krakow. The comparison took into account all the information obtained from the surveys. In addition, using a multicriteria approach, the final ranking of the set of journey planners was developed. The assessment was made on the basis of a set of nine criteria indicated by travellers as the most important ones. The obtained results showed disproportions in the functionality of particular solutions. They also indicated the apps that are most frequently and willingly used by local (urban city/agglomeration) travellers.]]>
<![CDATA[Wpływ zmian klimatu na drzewa ogrodów i parków rezydencji wilanowskiej]]> Mon, 16 May 2022 10:11:15 +0200 Domańska, Kamila; Kuśmierski, Jacek
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Abstrakt: Global climate changes carry a number of negative weather events, above all fluctuations in precipitation sums and an increase in the frequency of extreme natural phenomena, e.g. storms, fires, floods, droughts. Some of them could be observed also in Warsaw and at Wilanów. Only in 2017 there were several strong thunderstorms, accompanied by gusty wind which knocked down trees and torrential downpours causing outflows of the Służewiecki Stream. These phenomena are intensified by specific conditions of the urban environment, a high urbanization process and an increasing car traffic. As a result, undesirable changes in the ecosystem and tree-bearing structure occur in the Wilanów Park. Tree reactions to climate change mainly concern on their physiological processes and phenological development, e.g. decrease in photosynthetic efficiency, phenophase cycle disturbance and other negative developmental anomalies. In addition, there is abiotic stress, increased susceptibility to diseases or pest attacks and general weakness of condition. Despite special care, many specimen trees in the historic park at Wilanów cannot be protected against climate changes. Due to bad condition or extinction, about 110 trees and old bushes were cut down in the years 2012–2017. Under uncertainties about the rate of negative changes in the natural environment and the possible scale of reactions of plant species, it is necessary to make a depth research to understand the impact of climate change on trees and to create a forecast of its further impact. Their results will provide the base for improvement of tree management practices and also preparation of necessary strategies to inhibiting the degradation of habitats and impoverishment of the plant landscape of Wilanów through climate change.]]>
<![CDATA[Development and performance measurement of an affordable unmanned surface vehicle (USV)]]> Mon, 16 May 2022 10:03:29 +0200 Setiawan, Joga Dharma; Septiawan, Muhammad Aldi; Ariyanto, Mochammad; Caesarendra, Wahyu; Munadi, M.; Alimi, Sabri; Sulowicz, Maciej
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Abstrakt: Indonesia is a maritime country that has vast coastal resources and biodiversity. To support the Indonesian maritime program, a topography mapping tool is needed. The ideal topography mapping tool is the Unmanned Surface Vehicle (USV). This paper proposes the design, manufacture, and development of an affordable autonomous USV. The USV which is composed of a thruster and rudder is quite complicated to build. This study employs rudderless and double thrusters as the main actuators. PID compensator is utilized as the feedback control for the autonomous USV. Energy consumption is measured when the USV is in autonomous mode. The Dynamics model of USV was implemented to study the roll stability of the proposed USV. Open-source Mission Planner software was selected as the Ground Control Station (GCS) software. Performance tests were carried out by providing the USV with an autonomous mission to follow a specific trajectory. The results showed that the developed USV was able to complete the autonomous missions with relatively small errors, making it suitable for underwater topography mapping.]]>
<![CDATA[Mechanical response of geopolymer foams to heating – managing coal gangue in fire-resistant materials technology]]> Mon, 16 May 2022 09:38:33 +0200 Sitarz, Mateusz; Figiela, Beata; Łach, Michał; Korniejenko, Kinga; Mróz, Katarzyna; Castro-Gomes, João; Hager, Izabela
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Abstrakt: Two geopolymer foams were prepared from a thermally activated coal gangue containing kaolinite. As the foaming agent, aluminium powder and 36% hydrogen peroxide were used to obtain two levels of porosity. The materials’ high temperature performances were investigated: tensile and compressive strength evolution with temperature. This study shows that the mechanical performances of developed geopolymer foams are similar to foam concrete of the same apparent density. The geopolymer foams from coal gangue present stable mechanical performances up to 600 °C. When the glass transition temperature is achieved, sintering occurs and mechanical performance increases. SEM observations confirm the glass transition and densification of the matrix at temperatures above 800 °C. Moreover, the XRD measurements revealed a high amount of mullite that forms at 1000 °C that explained the observed strength increase. The synthesis of good-quality geopolymer foams from coal gangue and its application as a thermal barrier is feasible. The constant level of porosity and its stable character in the range of temperatures 20–1000 °C ensures stable thermal insulation parameters with increasing temperature, which is extremely important for fire protection.]]>
<![CDATA[Sustainable water management in a Krakow housing complex from the nineteen-seventies in comparison with a model Bio-Morpheme unit]]> Mon, 16 May 2022 08:13:47 +0200 Bonenberg, Wojciech; Rybicki, Stanisław M.; Schneider-Skalska, Grażyna; Stochel-Cyunel, Jadwiga
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Abstrakt: Cities grow through the addition of new housing structures, but the existing tissue is also modernized. Krakow, like any city with a historical origin, has typologically varied housing tissue. A large area of the city is occupied by multi-family panel-block housing estates which are being revitalised and the scope of this revitalization should include sustainable design elements. This paper determines the potential for implementing integrated water management, that utilizes rainwater in an existing basic urban unit that is a housing estate from the nineteen-seventies, located in Krakow (Poland), in conjunction with the Bio-Morpheme—the fractal reference model unit. The parameters of the Bio-Morpheme were established by earlier research as the optimum for a housing unit with regards to the circular economy and improving water use efficiency. The study covers the need to improve the quality of the housing environment, linked with the presence of natural elements, including a water reservoir, in the direct vicinity of the development. The analyses explored the potential to employ integrated water management with rainwater reuse in a basic urban unit (Krakow-Morpheme) and then compared the findings with the outcomes obtained by the proposed Bio-Morpheme complex. The results indicate that the potential to achieve a lower demand of water from the water supply system and to lower wastewater production were obtained, with a simultaneous opportunity to lay out an open water reservoir into the Krakow-Morpheme urban interior for improvement of the health value and well-being of inhabitants.]]>
<![CDATA[Skuteczne algorytmy diagnostyki stanu klatki silników indukcyjnych zaimplementowane w nowoczesnym uniwersalnym zabezpieczeniu cyfrowym]]> Mon, 16 May 2022 08:12:08 +0200 Duda, Arkadiusz; Sułowicz, Maciej; Tulicki, Jarosław; Węgiel, Tomasz; Iwiński, Marcin
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Abstrakt: Zabezpieczenia cyfrowe dedykowane dla silników indukcyjnych mogą realizować różne i nawet bardzo złożone, algorytmy ochrony silnika przed skutkami nieprzewidzianych zakłóceń jego bezawaryjnej pracy. Moc obliczeniowa aktualnie stosowanych cyfrowych urządzeń zabezpieczeniowych jest bardzo duża a pamięci do składowania rejestrowanych informacji przez te urządzenia może być dowolnie rozszerzana. Pozwala to producentom zabezpieczeń poszerzyć w łatwy sposób ich funkcjonalności o nowe wybrane funkcje np. do diagnostyki stanu silnika. W artykule skupiono się nad opisem algorytm do diagnostyki stanu klatki wirnika silników indukcyjnych podczas ustalonego stanu pracy zaimplementowanego w zabezpieczeniu cyfrowym silnika BEL_plus. Przedstawiono wyniki testów zabezpieczenia z zastosowanym algorytmem oraz propozycje wskaźnika diagnostycznego świadczącego o uszkodzeniu dla przykładowego silnika małej mocy z różnymi uszkodzeniami wirnika oraz wyniki testów dla silnika dużej mocy. Udowodniono, że zaproponowany algorytm działa poprawnie i pozwala na skuteczną ocenę stanu klatki nadzorowanych silników indukcyjnych.]]>
<![CDATA[System zbierania danych z czujników zabudowanych w smartfonach na potrzebę monitorowania wybranych parametrów pojazdów z napędem elektrycznym]]> Mon, 16 May 2022 08:04:33 +0200 Zielonka, Jakub; Sułowicz, Maciej; Czechowski, Mirosław
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Abstrakt: Monitorowanie stanu elementów napędu elektrycznego pojazdów elektrycznych jest kluczowym zagadnieniem w celu zapewnienia jak największej bezawaryjności maszyny oraz służy zminimalizowaniu kosztów związanych z ewentualnymi usterkami czy awariami. Artykuł przedstawia koncepcję systemu monitorującego wybrane sygnały diagnostyczne za pomocą kart pomiarowych oraz sensorów telefonu komórkowego – smartfonu. Badania przeprowadzono na pokładzie tramwaju miejskiego, gdzie monitorowano pracę silników indukcyjnych klatkowych będącymi głównymi elementami układu napędowego. Zebrane dane przy pomocy karty pomiarowej i czujników smartfonu, zestawiono i porównano w celu wyciągnięcia wniosków diagnostycznych.]]>
<![CDATA[Le collezioni naturali di Wilanów]]> Mon, 16 May 2022 08:00:10 +0200 Kuśmierski, Jacek
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<![CDATA["Citri et Aurea" – polsko-włoska współpraca ogrodowa]]> Mon, 16 May 2022 07:50:43 +0200 Kuśmierski, Jacek
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Abstrakt: Florenckie Ogrody Boboli i Muzeum Pałacu Króla Jana III w Wilanowie rozpoczęły współpracę poświęconą historycznym kolekcjom cytrusów. Niezwykła historia roślin sprzed wieków i wspólna troska o unikatowe na świecie dziedzictwo botaniczne, stały się przyczynkiem do ożywienia partnerskich relacji między Toskanią a Polską.]]>
<![CDATA[Rekonstrukcja ogrodu botanicznego w Queluz]]> Mon, 16 May 2022 07:41:13 +0200 Żołnierczuk, Maciej; Kuśmierski, Jacek
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Abstrakt: Królewska rezydencja położona 10 km na północny zachód od Lizbony stanowi jedno z najważniejszych historycznych założeń Portugalii. Od 2015 r. zarządzająca nią spółka Parques de Sintra realizuje kompleksowy program konserwatorski, w ramach którego odtworzono dawny ogród botaniczny.]]>
<![CDATA[Zawód: konserwator zabytkowej zieleni]]> Mon, 16 May 2022 07:38:11 +0200 Kuśmierski, Jacek
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Abstrakt: Jednym z największych wyzwań współczesnej architektury krajobrazu staje się skuteczna ochrona i konserwacja zabytkowej zieleni przy znaczącym braku odpowiednio przygotowanych specjalistów.]]>
<![CDATA[Katalońskie biennale]]> Mon, 16 May 2022 07:16:03 +0200 Kuśmierski, Jacek
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Abstrakt: Po raz dziesiąty Stowarzyszenie Architektów Katalonii oraz Politechnika Katalońska zaprosiły do Barcelony studentów i profesjonalistów z całego świata na wielkie wydarzenie poświęcone projektowaniu przestrzeni – Biennale Architektury Krajobrazu. Ambitny temat i bogaty program budziły wielkie oczekiwania, które niestety skończyły się sesją równie wielkich rozczarowań.]]>
<![CDATA[Mapping post-socialist changes in urban tissues: a comparative study of Belgrade and Krakow]]> Mon, 16 May 2022 07:01:15 +0200 Kantarek, Anna Agata; Kwiatkowski, Krzysztof; Korbel, Wojciech; Djokić, Vladan; Djordjević, Aleksandra; Niković, Ana; Samuels, Ivor
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Abstrakt: This project on post-socialist urban form in Belgrade and Krakow was undertaken over two years by the University of Belgrade, Faculty of Architecture, Cracow University of Technology and the Institute of Architecture and Urban and Spatial Planning of Serbia with field visits to both cities. A brief historical review and discussion of planning contexts is followed by an analysis of urban tissues from which five cases, characteristic of both cities, were selected for analysis. These range from peripheral areas to major city centre streets and typical modern developments. A GIS database was prepared for each case and comparisons made of land use patterns, the year-by-year establishment of new plots, Floor Area Ratio (FAR) and Building Area Ratio (BAR). Plot development is examined through the analysis of the relationship between construction year, plot size, the number of buildings on each plot, and increases of floor and building area ratio. The project highlights parallels between the impacts to which similar urban tissues in the two countries have been exposed during the post-socialist period and reveals the variety of problems and challenges of urban regulation, land ownership and housing investments in relation to post-socialist urban form.]]>
<![CDATA[Development of geopolymers based on fly ashes from different combustion processes]]> Thu, 12 May 2022 14:52:04 +0200 Pławecka, Kinga; Bazan, Patrycja; Lin, Wei-Ting; Korniejenko, Kinga; Sitarz, Maciej; Nykiel, Marek
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Abstrakt: The main aim of this research is to assess different fly ashes as raw materials for the manufacturing of geopolymers. Three different fly ashes have been investigated. First, a conventional fly ash from the Skawina coal power plant (Poland), obtained at a temperature of 900–1100 °C. Second, ultra-fine fly ash from a power plant in China; the side product received at 1300 °C. The third fly ash was waste was obtained after combustion in incineration plants. To predict the properties and suitability of materials in the geopolymerization process, methods based on X-ray analysis were used. The applied precursors were tested for elemental and chemical compounds. The investigations of geopolymer materials based on these three fly ashes are also presented. The materials produced on the basis of applied precursors were subjected to strength evaluation. The following research methods were applied for this study: density, X-ray fluorescence (XRF), X-ray diffraction analysis (XRD), Scanning Electron Microscopy (SEM), flexural and compressive strength. The obtained results show that materials based on fly ashes had a similar compressive strength (about 60 MPa), while significant differences were observed during the bending test from 0.1 to 5.3 MPa. Ultra-fine fly ash had a lower flexural strength compared to conventional fly ash. This study revealed the need for process optimization for materials based on a precursor from a waste incineration plant. ]]>
<![CDATA[Tribological and thermal behavior with wear identification in contact interaction of the Ti6Al4V-sintered carbide with AlTiN coatings pair]]> Wed, 11 May 2022 14:28:50 +0200 Bogdan-Chudy, Marta; Niesłony, Piotr; Gupta, Munish Kumar; Wojciechowski, Szymon; Maruda, Radosław W.; Gawlik, Józef; Królczyk, Grzegorz M.
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Abstrakt: Due to high demand of titanium and its alloys in modern manufacturing sectors, the high reactivity, poor conductivity and its functionality with other materials is still cumbersome. Therefore, it’s very imperative to study the tribological, thermal and wear behavior of Ti6Al4V alloy against other effective materials like carbides etc. In this holistic work, the pin on disc tests were conducted on Ti6Al4V alloy against PVD-Al00.55 Ti 0.45 N coated carbide pin. Then, the contact temperature, surface topography and wear behavior of pin and material were studied with the help of Scanning Electron Microscope (SEM). The results reveal that the effect of sliding distance on friction coefficient value is very low. On the other hand, the micrographs of wear surface reveal that the sliding distance plays a major role in generation of abrasion marks with adhesive joints as well cold weld junctions. Further, the results of friction coefficient values and the interquartile range (IQR) confirmed the satisfactory range of 14%. Moreover, the average coefficient of friction values were obtained in the range of −7.2–4.6%.]]>
<![CDATA[Pierwszy na ziemiach polskich rządowy konserwator zabytków : w 75. rocznicę śmierci prof. Tadeusza Szydłowskiego]]> Wed, 11 May 2022 12:27:28 +0200 Gaczoł, Andrzej; Dobosz, Piotr
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]]>
<![CDATA[Niestrudzony inwentaryzator zabytków]]> Wed, 11 May 2022 12:24:55 +0200 Gaczoł, Andrzej; Dobosz, Piotr
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<![CDATA[1D and 2D finite-difference operators for periodic functions on arbitrary mesh]]> Wed, 11 May 2022 12:17:33 +0200 Sobczyk, Tadeusz Jan
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Abstrakt: This paper presents novel discrete differential operators for periodic functions of one- and two-variables, which relate the values of the derivatives to the values of the function itself for a set of arbitrarily chosen points over the function’s area. It is very characteristic, that the values of the derivatives at each point depend on the function values at all points in that area. Such operators allow one to easily create finite-difference equations for boundary value problems. The operators are addressed especially to nonlinear differential equations.]]>
<![CDATA[Energy efficiency improvement by using hygrothermal diagnostics algorithm for historical religious buildings]]> Wed, 11 May 2022 12:00:58 +0200 Fedorczak-Cisak, Małgorzata; Radziszewska-Zielina, Elżbieta; Białkiewicz, Andrzej; Prociak, Aleksander; Steidl, Tomasz; Tatara, Tadeusz; Żychowska, Maria; Muniak, Damian Piotr
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Abstrakt: Improving the energy quality and performance of historic buildings is a complicated task, both from the research, design and executive point of view. The aim of this paper and the main motivation of the authors was to improve the energy quality and energy performance of one of the building partitions of a historic church in terms of not deteriorating both the technical condition of the element to be modernised, and maintaining an interior microclimate appropriate for such objects. The authors hypothesised that the algorithm proposed should contain both typical tests as well as modern diagnostic and simulation methods that allow to predict the results of the impact of the planned changes on historic elements. The conclusions confirmed that the use of the proposed research methods allows for the simultaneous improvement of energy performance and the preservation of historic elements, and preventing the deterioration of the specific microclimate of the building. With such measures, it was possible to reduce the annual heat demand indicator for heating the building from 253.73 [kWh/(m2y)] to 77.59 [kWh/(m2y)] constituting about 69%.]]>
<![CDATA[Finite-difference operators for 2D problems]]> Wed, 11 May 2022 11:56:07 +0200 Sobczyk, T.J.
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Abstrakt: This paper presents the concept of using algorithms for reducing the dimensions of finite-difference equations of two-dimensional (2D) problems, for second-order partial differential equations. Solutions are predicted as two-variable functions over the rectangular domain, which are periodic with respect to each variable and which repeat outside the domain. Novel finite-difference operators, of both the first and second orders, are developed for such functions. These operators relate the value of derivatives at each point to the values of the function at all points distributed uniformly over the function domain. A specific feature of the novel operators follows from the arrangement of the function values as well as the values of derivatives, which are rectangular matrices instead of vectors. This significantly reduces the dimensions of the finite-difference operators to the numbers of points in each direction of the 2D area. The finite-difference equations are created exemplary for elliptic equations. An original iterative algorithm is proposed for reducing the process of solving finite-difference equations to the multiplication of matrices.]]>
<![CDATA[Comparative analysis of different fertilization system types. Case study applied in Poland]]> Wed, 11 May 2022 11:51:49 +0200 Kowalski, Zygmunt; Makara, Agnieszka; Olczak, Piotr
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Abstrakt: In this study, we analyzed factors involved in pig manure fertilization systems for arable lands (30,000 ha) and five Polish pig farms, that produced approximately 240,000 t/year pig manure. Fertilizing component demands for N, P, K and Mg on Agrifarm Company farms and liquid manure doses were estimated, based on determination in soils N, P, K. Crops yields obtained were also presented. Finally, pig manure transfer and injection costs were assessed in terms of transport distances and soil demands for nutrients. Calculated manure doses were on average 46 m3/ha. Natural fertilizers covered on average 70% of the N demand, 77% of the P demand, and 102% of the K demand in tested soils. On average, 122,029 t/year of pig manure (51% of manure produced) was utilized for fertilization purposes, but only for cases when the distance between fertilized fields and pig farms was up to 10 km. Practically pig manure is stored six months per year, but having sufficiently large areas of arable fields, it is possible to use the whole amount of pig manure produced in whole year and stored six months, but these areas should be located nearby pig farms. The costs of pig manure transfer and injection into lands were assessed in terms of manure transport distances, and soil demands for nutrients. Results showed that manure fertilization at the transport distance of 29 km pig manure fertilization costs should be most advantageous and most real to implementation in agricultural practice and 52 km was maximum cut-off pig manure transport distance.]]>
<![CDATA[Alginate hydrogels with Aloe vera: the effects of reaction temperature on morphology and thermal properties]]> Wed, 11 May 2022 11:48:28 +0200 Bialik-Wąs, Katarzyna; Raftopoulos, Konstantinos N.; Pielichowski, Krzysztof
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Abstrakt: In this study, we investigated the impact of reaction temperature on the physicochemical, structural, morphological, and thermal properties of sodium alginate/poly (vinyl alcohol)-based hydrogels, both in the pure form and with the addition of 20% (v/v) Aloe vera solution. The materials were prepared by chemical crosslinking at temperatures in the range of 65–75 ◦C. Poly (ethylene glycol) diacrylate was used as a crosslinking agent. The extent to which the crosslinking reaction proceeded was studied as a function of the reaction temperature, along with the thermal properties and morphology of the final materials. A measurement of gel fraction, in agreement with differential scanning calorimetry and Fourier transform infrared spectroscopy, showed that a higher temperature of reaction promoted the crosslinking reaction. On the basis of the aforementioned techniques, as well as by energy dispersive X-ray analysis under an electron microscope, it was also shown that the bioadditive Aloe vera promoted the crosslinking reaction.]]>
<![CDATA[The impact of the Matricaria chamomilla L. Extract, starch solution and the photoinitiator on physiochemical properties of acrylic hydrogels]]> Wed, 11 May 2022 11:45:35 +0200 Jamroży, Mateusz; Głąb, Magdalena; Kudłacik-Kramarczyk, Sonia; Drabczyk, Anna; Gajda, Paweł; Tyliszczak, Bożena
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Abstrakt: Matricaria chamomilla L. extract is well-known for its therapeutic properties; thus, it shows potential to be used to modify materials designed for biomedical purposes. In this paper, acrylic hydrogels modified with this extract were prepared. The other modifier was starch introduced into the hydrogel matrix in two forms: room-temperature solution and elevated-temperature solution. Such hydrogels were synthesized via UV radiation, while two types of photoinitiator were used: 2-hydroxy2-methylpropiophenone or phenylbis(2,4,6-trimethylbenzoyl) phosphine oxide. The main task of performed research was to verify the impact of particular modifiers and photoinitiator on physicochemical properties of hydrogels. Studies involved determining their swelling ability, elasticity, chemical structure via FTIR spectroscopy and surface morphology via the SEM technique. Incubation of hydrogels in simulated physiological liquids, studies on the release of chamomile extract from their matrix and their biological analysis via MTT assay were also performed. It was demonstrated that all investigated variables affected the physicochemical properties of hydrogels. The modification of hydrogels with chamomile extract reduced their absorbency, decreased their thermal stability and increased the cell viability incubated with this material by 15%. Next, hydrogels obtained by using phenylbis(2,4,6-trimethylbenzoyl) phosphine oxide as a photoinitiator showed lower absorbency, more compact structure, better stability in SBF and a more effective release of chamomile extract compared to the materials prepared by using 2-hydroxy-2-methylpropiophenone. It was proved that, by applying adequate reagents, including both photoinitiator and modifiers, it is possible to obtain hydrogels with variable properties that will positively affect their application potential.]]>
<![CDATA[Różany świat Wilanowa]]> Wed, 11 May 2022 11:41:15 +0200 Kuśmierski, Jacek
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Abstrakt: Róże bez wątpienia są królowymi wśród kwiatów. Ich niezwykłe piękno i zmysłowość w połączeniu z szerokim zastosowaniem sprawiły, że stały się jednymi z najbardziej uwielbianych roślin w historii. W ogrodach wilanowskich pojawiły się już w czasach króla Jana III, ale najpełniej prezentują swoje bogactwo współcześnie.]]>
<![CDATA[Damage detection for conveyor belt surface based on conditional cycle generative adversarial network]]> Mon, 09 May 2022 14:31:11 +0200 Guo, Xiaoqiang; Liu, Xinhua; Królczyk, Grzegorz; Sulowicz, Maciej; Glowacz, Adam; Gardoni, Paolo; Li, Zhixiong
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Abstrakt: The belt conveyor is an essential piece of equipment in coal mining for coal transportation, and its stable operation is key to efficient production. Belt surface of the conveyor is vulnerable to foreign bodies which can be extremely destructive. In the past decades, much research and numerous approaches to inspect belt status have been proposed, and machine learning-based non-destructive testing (NDT) methods are becoming more and more popular. Deep learning (DL), as a branch of machine learning (ML), has been widely applied in data mining, natural language processing, pattern recognition, image processing, etc. Generative adversarial networks (GAN) are one of the deep learning methods based on generative models and have been proved to be of great potential. In this paper, a novel multi-classification conditional CycleGAN (MCC-CycleGAN) method is proposed to generate and discriminate surface images of damages of conveyor belt. A novel architecture of improved CycleGAN is designed to enhance the classification performance using a limited capacity images dataset. Experimental results show that the proposed deep learning network can generate realistic belt surface images with defects and efficiently classify different damaged images of the conveyor belt surface.]]>
<![CDATA[Closed-form analytical solution to the problem of bending of a multilayer composite beam – derivation and verification]]> Mon, 09 May 2022 12:28:17 +0200 Szeptyński, Paweł
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Abstrakt: A linear elastic model of a bent multilayer composite beam is considered. Closed-form analytical solution is derived with the use of method of generalized eigenvectors. Deformation predicted by the analytical model is compared with the results of a three-dimensional linear Finite Element Analysis as well as with the results of experiments performed on three types of multilayer composite beams.]]>
<![CDATA[Wpływ kąta rastrowania na właściwości mechaniczne polimeru PLA-IMPACT w technologii druku 3D]]> Mon, 09 May 2022 12:24:45 +0200 Boroń, Paweł; Dulińska, Joanna; Jurkowska, Nadzieja; Tatara, Tadeusz
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Abstrakt: Celem pracy jest poznanie możliwości i uwarunkowań stosowania modeli wykonanych w technologii druku 3D do badań dynamicznych. Zaprezentowano metodę i wyniki badań określających parametry fizykomechaniczne polimeru PLA-IMPACT drukowanego z różnymi kątami rastrowania. Badania wykazały, że wartość modułu sprężystości polimeru nie zależy od kąta rastrowania, natomiast na granicę plastyczności ma wpływ kierunek laminacji, co wpływa w istotny sposób na realizację modeli obiektów do badań dynamicznych.]]>
<![CDATA[Green, one-pot synthesis of 1,2-oxazine-type herbicides via non-catalyzed Hetero Diels-Alder reactions comprising (2E)-3-aryl-2-nitroprop-2-enenitriles]]> Mon, 09 May 2022 12:22:14 +0200 Woliński, Przemysław; Kącka-Zych, Agnieszka; Mirosław, Barbara; Wielgus, Ewelina; Olszewska, Aleksandra; Jasiński, Radomir
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Abstrakt: In the framework of this paper we describe a new, green procedure for the synthesis of a series of 1,2-oxazine N-oxide moieties via Hetero Diels-Alder (HDA) reaction with the participation of (2E)-3-aryl-2-nitroprop-2-ene-nitriles. For the contrast of most known HDA reactions, the described process is realized without presence of Lewis acid-type catalyst as well as under mild conditions, with full atomic economy and selectivity. Additionally, we established, that the reaction process can be characterized with Molecular Electron Density Theory (MEDT).]]>
<![CDATA[Optimizing the l/s ratio in geopolymers for the production of large-size elements with 3D printing technology]]> Mon, 09 May 2022 12:16:04 +0200 Marczyk, Joanna; Ziejewska, Celina; Pławecka, Kinga; Bąk, Agnieszka; Łach, Michał; Korniejenko, Kinga; Hager, Izabela; Mikuła, Janusz; Lin, Wei-Ting; Hebda, Marek
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Abstrakt: Geopolymer concretes can be a viable alternative to conventional Portland cement-based materials. In their design, it is important to maintain an appropriate liquid-to-solid ratio (L/S), which affects several properties, such as the compressive strength, water absorption, and frost resistance. The objective of this paper is to analyze the influence of the fly-ash and metakaolin precursor types for three different L/S ratios: 0.30, 0.35, and 0.45. The results of the physical and mechanical properties, including the apparent density and compressive strength, as well the durability parameters, including frost resistance and water penetration depth, are presented in this paper. It was found that as the L/S ratio decreased, the average compressive strength increased for all materials. After freeze–thaw cycles, decreases in the compressive strength properties were observed for all types of materials—metakaolin- and fly ash-based—irrespective of the L/S ratio. Moreover, the frost resistance of geopolymers increased with the increase in the L/S ratio. The printability of the mixes was also verified in order to confirm the application of the developed materials to additive manufacturing processes. ]]>
<![CDATA[Is a house named "yellow" really yellow? Survey on the perception and naming of the yellow color on building facades depending on its hue, lightness and saturation]]> Fri, 06 May 2022 07:07:23 +0200 Tarajko-Kowalska, Justyna
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Abstrakt: The article's primary goal is to present the author's online color survey results. The study was aimed at checking which colors chosen from NCS Color System's four yellowish hue groups: G80Y, G90Y, Y, and Y10R are considered as "yellow". The 28 nuances differed in hue, lightness, and chroma, were presented separately on color swatches and building facades. At first, the respondents assessed the yellowness of selected colors and then indicated the most appropriate ones for the color term "yellow". The analysis of the 444 results confirmed the high importance of saturation and lightness (whiteness/blackness level) in color appearance and naming. The research proved that a given color is likely described as "yellow" only when its parameters of lightness and saturation are similar to the prototype of the yellow color category, characterized by high saturation and high intrinsic lightness. The clarity of the hue was also a significant factor.]]>
<![CDATA[Analiza możliwości wykorzystania sensorów zabudowanych w smartfonach w systemach diagnostycznych]]> Fri, 06 May 2022 07:01:25 +0200 Zielonka, Jakub; Sułowicz, Maciej; Czechowski, Mirosław
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Abstrakt: Rozwój techniki wprowadza nowe możliwości w zagadnieniach diagnostyki i monitoringu parametrów pojazdów elektrycznych. Do takich nowości zaliczamy telefony komórkowe, które w ostatnich latach znacznie rozwinęły swoje możliwości. Obecne smartfony posiadają w swych podzespołach zestaw czujników, których wykorzystanie w odpowiedni sposób może dostarczyć informacji dla zagadnień diagnostycznych. Artykuł przedstawia system monitorujący wybrane sygnały diagnostyczne za pomocą karty pomiarowej oraz sensorów smartfonu. Badania przeprowadzono na pokładzie tramwaju, gdzie monitorowano pracę silników indukcyjnych klatkowych. Zebrane w ten sposób dane poddano analizie pod kątem użyteczności w aspektach diagnostyki i innych.]]>
<![CDATA[Static and fatigue behaviour of double-lap adhesive joints and notched metal samples reinforced by composite overlays]]> Thu, 05 May 2022 09:48:22 +0200 Romanowicz, Paweł J.; Szybiński, Bogdan; Wygoda, Mateusz
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Abstrakt: The use of composite overlays to increase the fatigue life of notched steel samples is discussed in this paper. For such purposes, in the first set of studies, static and fatigue tests as well as the detailed analytical and numerical analyses for samples with double-lap joints were performed. Based on such studies, the shapes of the composite overlays were set. For a better understanding of the failure forms of the investigated adhesive joints, the experimental studies were monitored with the use of digital image correlation. In the second set of experimental studies, the static and fatigue tensile tests were performed for steel samples with a rectangular opening with rounded corners reinforced by composite overlays. The different shapes (square 45 × 45 mm and long stripes 180 × 15 mm) and composite materials (GFRP and CFRP) were used as overlays. The obtained improvement of fatigue life was in the range of 180–270% in the case of the rectangular overlays and 710% in the case of application of the overlays in the form of the long stripes. This was also confirmed by numerical analyses in which a reduction in the stress concentration factor from 2.508 (bare sample) through 2.014–2.183 (square 45 × 45 mm overlays) to 1.366 (overlays in the form of long stripes 180 × 15 mm) was observed. ]]>
<![CDATA[The influence of tuff particles on the properties of the sintered copper matrix composite for application in resistance welding electrodes]]> Wed, 04 May 2022 09:23:38 +0200 Łach, Michał; Korniejenko, Kinga; Balamurugan, Ponnambalam; Uthayakumar, Marimuthu; Mikuła, Janusz
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Abstrakt: This paper presents modern copper-matrix composite materials in which volcanic tuff particles are used as a reinforcing phase. The aim of the research was to determine the optimal shares of volcanic tuff additive based on such criteria as softening temperature, relative density, electrical conductivity, and hardness. The properties of the produced and tested composites allowed us to determine the usefulness of this type of material for resistance welding electrodes. To confirm the assumptions made, preliminary investigations of the durability and behavior of electrodes made of the tested material during the processes of welding non-alloy steel sheets were carried out. As a result of the research, it was discovered that the addition of 5% tuff produces the best results in this type of composite. It was found that for the sample with a 5% share of tuff, a high softening point above 600 °C was obtained, high hardness after densification at the level of 62 HRB, and high relative density of approximately 95% and very good conductivity at the level of approximately 45 MS/m. The conducted tests did not show any electrode wear different from the commonly used alloys for resistance welding. ]]>