Nowe zasoby w kolekcji Artykuły i czasopisma http://suw.biblos.pk.edu.pl/ Biblioteka Politechniki Krakowskiej lipinska@biblos.pk.edu.pl 60 <![CDATA[Near-to-zero switching synchronization approach for DC electromagnet actuated relays]]> Thu, 14 Oct 2021 14:35:46 +0200 Smugala, D.; Gebczyk, J.; Wawro, M.; Czuchra, W.
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Abstrakt: This paper puts forward an idea for DC electromagnetically (EM) actuated switching devices operation improvement by means of an electronic controller application. The idea is aimed at applying compensation for the movable armature inertia and the time required for coil (de)energization. Based on the results of the measurements of the tested contactors switching parameters, the most efficient (de)energizing conditions for neartozero synchronized switching (NZSS) method application were determined. The NZSS process realization approach operates on the principle of controlling the driving coil supply voltage delivery moment. By means of the same controller circuit, voltage-zero-synchronized (VZS) contacts making and current-zero-synchronized (CZS) contacts breaking operations were realized. The method was experimentally verified for various supply conditions and load parameters. Long-term tests confirm the suitability of the method for low-voltage (LV) EM actuated switching devices. The circuit was able to control various EM drives with no modification required for the structure in which it was used.]]>
<![CDATA[Właściwości mechaniczne i użytkowe rur stalowych w gatunku C/6/X52]]> Thu, 14 Oct 2021 14:32:36 +0200 Jonderko, Henryk; Psonka, Wojciech; Stankiewicz, Marek
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<![CDATA[Właściwości mechaniczne i użytkowe rur stalowych w gatunku C/6/X52]]> Thu, 14 Oct 2021 14:12:54 +0200 Jonderko, Henryk; Psonka, Wojciech; Stankiewicz, Marek
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<![CDATA[Podstawowe własności mechaniczne stali S.A. 387 Grade 22 Class 2 w zakresie temperatury eksploatacji]]> Thu, 14 Oct 2021 14:10:53 +0200 Stankiewicz, Marek; Baran, Marek; Stępień, Tadeusz
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<![CDATA[Weryfikacja młotów udarnościowych w świetle wymagań normy ASTM E23 i procedury NIST]]> Thu, 14 Oct 2021 14:09:06 +0200 Stankiewicz, Marek; Cęckiewicz, Stanisław
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<![CDATA[Właściwości mechaniczne blach stalowych w zbiornikach paliwowych narażonych na długotrwałe oddziaływanie korozji atmosferycznej]]> Thu, 14 Oct 2021 14:06:53 +0200 Siudut, Janusz; Stankiewicz, Marek
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<![CDATA[Ocena wiarygodności badań twardości złączy spawanych przenośnymi twardościomierzami MICRODUR]]> Thu, 14 Oct 2021 14:04:42 +0200 Stankiewicz, Marek; Psonka, Wojciech; Faligowski, Andrzej
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<![CDATA[Tradycja na nowo odkryta]]> Thu, 14 Oct 2021 14:02:21 +0200 Olesiak, Justyna
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Abstrakt: Artykuł we wstępie przybliża aspekty programowe, funkcjonalne i estetyczne tradycyjnego budownictwa łemkowskiego w regionie Sądecczyzny. Podjęto próbę syntezy i na jej podstawie sformułowania wytycznych projektowych dla obiektów współczesnych. Jak się okazuje, wiele prawideł, według których kształtowano tradycyjne budynki, znajduje odzwierciedlenie w wymogach architektury energooszczędnej i przyjaznej środowisku. Przedstawiona w artykule propozycja projektowa - dom energooszczędny w Królowej Górnej - wpisuje się w nurt architektury wernakularnej i zorientowanej na zrównoważony rozwój.]]>
<![CDATA[Spawanie rur w gatunku Gr. C/6/X52 drutem proszkowym]]> Thu, 14 Oct 2021 13:13:34 +0200 Stankiewicz, Marek; Jonderko, Henryk; Kijowski, Dariusz; Psonka, Wojciech
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Abstrakt: W publikacji przedstawiono własności mechaniczne i użytkowe rur w potrójnym gatunku Gr. C/6/X52 wg ASTM i API 5L oraz zaproponowano technologię spawania FCAW z użyciem drutu rdzeniowego OK Tubrod 15.11 gwarantującą uzyskanie wymaganych własności mechanicznych, w tym wysokiej udarności KCV w temperaturze -50°C.]]>
<![CDATA[Porównanie różnych metod wyznaczania granicy plastyczności w statycznej próbie rozciągania metali i stopów]]> Thu, 14 Oct 2021 13:08:23 +0200 Stankiewicz, Marek; Psonka, Wojciech
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<![CDATA[Granice akceptowalności wyników kontroli jakości żaroodpornych wymurówek pieców grzewczych]]> Thu, 14 Oct 2021 13:05:46 +0200 Stankiewicz, Marek; Rybak, Marek
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<![CDATA[Review of solutions for the use of phase change materials in geopolymers]]> Thu, 14 Oct 2021 10:06:55 +0200 Łach, Michał; Pławecka, Kinga; Bąk, Agnieszka; Adamczyk, Marcin; Bazan, Patrycja; Kozub, Barbara; Korniejenko, Kinga; Lin, Wei-Ting
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Abstrakt: The paper deals with the possibility of using Phase Change Materials (PCM) in concretes and geopolymer composites. The article presents the most important properties of PCM materials, their types, and their characteristics. A review of the latest research results related to their use in geopolymer materials is presented. The benefits of using PCM in building materials include the improvement of thermal comfort inside the building, and also the fact that the additive in the form of PCM reduces thermal gradients and unifies the temperature inside the concrete mix, which can reduce the risk of cracking. The paper also presents a critical analysis related to the feasibility of mass scale implementations of such composites. It was found that the use of PCM in sustainable construction is necessary and inevitable, and will bring a number of benefits, but it still requires large financial resources and time for more comprehensive research. Despite the fact that PCM materials have been known for many years, it is necessary to refine their form to very stable phases that can be used in general construction as well as to develop them in a cost-effective form. The selection of these materials should also be based on the knowledge of the matrix material.]]>
<![CDATA[Investigation on green synthesis, biocompatibility, and antibacterial activity of silver nanoparticles prepared using Cistus incanus]]> Thu, 14 Oct 2021 08:48:36 +0200 Florkiewicz, Wioletta; Pluta, Klaudia; Malina, Dagmara; Rudnicka, Karolina; Żywicka, Anna; Duarte Guigou, Martin; Tyliszczak, Bożena; Sobczak-Kupiec, Agnieszka
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Abstrakt: This paper describes the plant-mediated preparation of silver nanoparticles with aqueous extract and infusion of Cistus incanus leaves. To evaluate aqueous extract and infusion antioxidant capacity and total phenolic content the DPPH and Folin–Ciocalteau methods were utilized. The antioxidant capacity and total phenolic content of extract and infusion were equal to 85.97 ± 6.54 mg gallic acid equivalents per gram of dry weight.; 10.76 ± 0.59 mg/mL and 12.65 ± 1.04 mg gallic acid equivalents per gram of dry weight.; 3.10 ± 0.14 mg/mL, respectively. The formed nanoparticles displayed the characteristic absorption band in the 380–450 nm wavelength range. The average size of particles was in the 68.8–71.2 nm range. Morphology and phase composition analysis revealed the formation of spherical nanoparticles with a face-centred cubic structure. Immune compatibility tests of nanoparticles and plant extracts showed no activation of the THP1-XBlue™ monocyte. Cytotoxicity tests performed with L929 mice fibroblasts showed that nanoparticles should be utilized at a concentration of 16 ppm. The minimum inhibitory concentrations determined with the microdilution method for nanoparticles prepared with plant infusion for S. aureus and S. epidermidis were 2 ppm and 16 ppm, respectively.]]>
<![CDATA[Values of the historical parks and gardens of psychiatric hospitals in Kulparków and Kobierzyn as the basis for their revalorization]]> Thu, 14 Oct 2021 08:44:42 +0200 Staniewska, Anna; Petryshyn, Halyna; Lukashchuk, Halyna; Kliusa, Tetiana; Koprynia, Karolina
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Abstrakt: This paper discusses the revalorization of a historical park landscape with therapeutic features of psychiatric hospitals from the second half of the nineteenth and at the beginning of the twentieth century. It presents the history and architectural and landscape values of historical complexes of psychiatric hospitals in Kulparków near Lviv and in Kobierzyn near Cracow. The main features of these park and garden compositions are presented based on historic data and archival sources, the literature, surveys and field research. Despite the passage of time, the preservation of the original park compositions allows one to highlight their primary features and supplement them with harmoniously chosen contemporary elements. As a proposal of contemporary actions, revalorization concepts prepared in recent years developed as part of Master’s thesis projects were presented.]]>
<![CDATA[Formulation and evaluation of organo-mineral fertilizers based on sewage sludge optimized for maize and sunflower crops]]> Thu, 14 Oct 2021 08:41:52 +0200 Kominko, Halyna; Gorazda, Katarzyna; Wzorek, Zbigniew
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Abstrakt: The depletion of natural resources, energy consumption and environmental issues relating to fertilizer production processes are driving a move towards a more sustainable use of resources and the recycling of nutrients. With regard to the fertilizer industry, this gives the opportunity to use the fertilizing potential of alternative raw materials. This paper evaluates the possibility of using dried sewage sludge in the manufacture of organo-mineral fertilizers. Fertilizers based on sewage sludge with an addition of poultry litter ash and mineral fertilizers were developed and characterized in the study. It was possible to produce multicomponent organo-mineral fertilizers with optimized compositions for maize and sunflower crops, characterized by total nutrient content over 20%. Moreover, they contained beneficial secondary nutrients and micronutrients originated from waste materials. The fertilizers were free of pathogens and fulfilled the requirements related to heavy metal content according to Polish legislation. The method of manufacturing organo-mineral fertilizers based on waste materials is a simple waste management solution offering organic matter and nutrient recycling in line with the circular economy and reducing reliance on imported raw materials.]]>
<![CDATA[Evaluating the environmental impact of using cargo bikes in cities: a comprehensive review of existing approaches]]> Thu, 14 Oct 2021 08:39:20 +0200 Vasiutina, Hanna; Szarata, Andrzej; Rybicki, Stanisław
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Abstrakt: The impact of the use of cargo bicycles for delivery processes on the environment is undeniably positive: it leads to the reduction of pollutants, noise, and vibrations caused by traditional vehicles; decreases traffic jams; causes more effective use of public space; and others. But how should such an effect be measured? What tools should be used to justify the necessity for change to more sustainable means of transport? How can we improve the state of the environment considering the interests of logistics service providers? There is a large amount of scientific literature dedicated to this problem: by using different modeling approaches, authors attempt to address the issue of sustainable transport. This paper conducts a literature review in the field of green cargo deliveries, investigates the benefits and drawbacks of integrating cargo bikes in urban logistics schemes, and examines methodologies and techniques for evaluating the impact of using cargo bicycles on the environment. By providing an opportunity to get acquainted with the situation in the sphere of green deliveries, the authors aim to encourage a breakthrough in the field of sustainable transport that may be achieved by using cargo bikes in modern cities. We review the existing approaches and tools for modeling transport emissions and state the significant positive environmental consequences.]]>
<![CDATA[Operational problems of tramway infrastructure in sharp curves]]> Thu, 14 Oct 2021 08:36:02 +0200 Czyczuła, Włodzimierz; Rochel, Maciej
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Abstrakt: Elements of the tramway track that require special attention in the design and maintenance of the tramway infrastructure are sharp curves (curves with small radii). In such places, there are a number of unfavourable operational problems, which are discussed in the article below. It describes the characteristics of such geometric elements and analyses the interaction of the wheel-rail system. Moreover, the most important operational problems are presented, such as the wear of wheels and tramway rails, the buckling of the rails, and noise and vibrations occurring during the passage of the tram. Methods of reducing unfavourable phenomena occurring on curves in the tramway infrastructure were also highlighted.]]>
<![CDATA[Właściwości mechaniczne rur ze stali w gatunku Gr. 6 według ASTM A 333]]> Thu, 14 Oct 2021 08:32:51 +0200 Jonderko, Henryk; Psonka, Wojciech; Stankiewicz, Marek
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<![CDATA[Właściwości połączeń spawanych materiałów różnorodnych]]> Thu, 14 Oct 2021 08:27:51 +0200 Tasak, Edmund; Stankiewicz, Marek; Gierlicki, Ryszard; Ziewiec, Krzysztof
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<![CDATA[Zmiana własności plastycznych po spawaniu stali 2,25Cr-1Mo w czasie obróbki cieplnej]]> Thu, 14 Oct 2021 08:25:33 +0200 Stankiewicz, Marek; Tasak, Edmund
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<![CDATA[Połączenia spawane rur Gr. C/6/X52 wg ASTM i API – własności mechaniczne]]> Thu, 14 Oct 2021 08:23:03 +0200 Stankiewicz, Marek; Jonderko, Henryk; Kijowski, Dariusz; Psonka, Wojciech; Tasak, Edmund
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<![CDATA[Change in the ductility properties of 2,25Cr–1Mo steel during post-welding heat treatment]]> Thu, 14 Oct 2021 08:20:27 +0200 Stankiewicz, M.; Tasak E.
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<![CDATA[Ocena podstawowych właściwości stali S460M w szerokim zakresie temperatur obniżonych i podwyższonych]]> Thu, 14 Oct 2021 08:18:04 +0200 Stankiewicz, Marek
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<![CDATA[Porównanie wyników badań udarności stali konstrukcyjnych określonych w oparciu o normy PN-EN 10045-1 i ASTM E23]]> Thu, 14 Oct 2021 08:15:21 +0200 Stankiewicz, Marek; Ziółkowski, Eugeniusz
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<![CDATA[Kwasoodporna stal ASTM 304L o nietypowym stanie dostawy]]> Thu, 14 Oct 2021 08:11:50 +0200 Stankiewicz, Marek; Stępień, Tadeusz
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<![CDATA[Własności połączeń spawanych stali P22 po stopniowym chłodzeniu]]> Wed, 13 Oct 2021 14:50:23 +0200 Stankiewicz, Marek; Tasak, Edmund
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<![CDATA[S690QL – krajowa stal klasy N-A-XTRA]]> Wed, 13 Oct 2021 14:48:13 +0200 Stankiewicz, Marek; Prószyński, Maciej
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Abstrakt: W artykule przedstawiono wyniki badań fizykomechanicznych i strukturalnych stali S690QL, które wskazują na możliwość stosowania tej stali w wyższych temperaturach eksploatacji niż wynika to z zaleceń normy PN—EN 10137:2000. Jednocześnie wskazano na niedociągnięcia technologiczne w procesie wytwarzania skutkujące niedostateczną jednorodnością materiału.]]>
<![CDATA[PGS/HAp microporous composite scaffold obtained in the TIPS-TCL-SL method: an innovation for bone tissue engineering]]> Wed, 13 Oct 2021 13:18:15 +0200 Piszko, Paweł; Sobczak-Kupiec, Agnieszka
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Abstrakt: In this research, we synthesize and characterize poly(glycerol sebacate) pre-polymer (pPGS) (1H NMR, FTiR, GPC, and TGA). Nano-hydroxyapatite (HAp) is synthesized using the wet precipitation method. Next, the materials are used to prepare a PGS-based composite with a 25 wt.% addition of HAp. Microporous composites are formed by means of thermally induced phase separation (TIPS) followed by thermal cross-linking (TCL) and salt leaching (SL). The manufactured microporous materials (PGS and PGS/HAp) are then subjected to imaging by means of SEM and µCT for the porous structure characterization. DSC, TGA, and water contact angle measurements are used for further evaluation of the materials. To assess the cytocompatibility and biological potential of PGS-based composites, preosteoblasts and differentiated hFOB 1.19 osteoblasts are employed as in vitro models. Apart from the cytocompatibility, the scaffolds supported cell adhesion and were readily populated by the hFOB1.19 preosteoblasts. HAp-facilitated scaffolds displayed osteoconductive properties, supporting the terminal differentiation of osteoblasts as indicated by the production of alkaline phosphatase, osteocalcin and osteopontin. Notably, the PGS/HAp scaffolds induced the production of significant amounts of osteoclastogenic cytokines: IL-1β, IL-6 and TNF-α, which induced scaffold remodeling and promoted the reconstruction of bone tissue. Initial biocompatibility tests showed no signs of adverse effects of PGS-based scaffolds toward adult BALB/c mice.]]>
<![CDATA[Review of the applications of biomedical compositions containing hydroxyapatite and collagen modified by bioactive components]]> Wed, 13 Oct 2021 13:09:35 +0200 Sobczak-Kupiec, Agnieszka; Drabczyk, Anna; Florkiewicz, Wioletta; Głąb, Magdalena; Kudłacik-Kramarczyk, Sonia; Słota, Dagmara; Tomala, Agnieszka; Tyliszczak, Bożena
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Abstrakt: Regenerative medicine is becoming a rapidly evolving technique in today’s biomedical progress scenario. Scientists around the world suggest the use of naturally synthesized biomaterials to repair and heal damaged cells. Hydroxyapatite (HAp) has the potential to replace drugs in biomedical engineering and regenerative drugs. HAp is easily biodegradable, biocompatible, and correlated with macromolecules, which facilitates their incorporation into inorganic materials. This review article provides extensive knowledge on HAp and collagen-containing compositions modified with drugs, bioactive components, metals, and selected nanoparticles. Such compositions consisting of HAp and collagen modified with various additives are used in a variety of biomedical applications such as bone tissue engineering, vascular transplantation, cartilage, and other implantable biomedical devices.]]>
<![CDATA[Polymer-ceramic biocomposites based on PVP/histidine/hydroxyapatite for hard tissue engineering applications]]> Wed, 13 Oct 2021 13:02:08 +0200 Sobczak-Kupiec, Agnieszka; Tomala, Agnieszka Maria; López, Cristina Domínguez; Drabczyk, Anna; Tyliszczak, Bożena
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Abstrakt: Polymer and hydroxyapatite (HAP) composites have growing interest in bone regeneration. Commonly used for these applications is polyvinylpyrrolidone (PVP), which represents excellent biological inertness, is biocompatible, and do not adversely interact with HAP. For this reason, in our studies, we have focused on 3-igreedient biocomposites based on PVP/histidine/HAP investigating their mechanical performance, morphology, swelling property and incubation response. The objective is to determine the effect of histidine on the UV cross-linked hydroxyapatite-polymers composites particularly focused on the role of their composition on structure, mechanical properties, and biocompatibility. The results confirm bioactivity of this material and it desirable features for orthopedics.]]>
<![CDATA[Tradycja i współczesność w architekturze Zakopanego. Wybrane aspekty]]> Wed, 13 Oct 2021 12:32:28 +0200 Węcławowicz-Gyurkovich, Ewa; Godula-Węcławowicz, Róża
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Abstrakt: Drewniana architektura Zakopanego, intensywnie rozwijającego się z końcem XIX i w pierwszej dekadzie XX wieku, stanowi odmienny od innych regionów fenomen. Jest wypadkową tradycji kultury górali podhalańskich i motywów zaczerpniętych ze stylistyki historycznej, twórczo przetworzonych przez Stanisława Witkiewicza w oryginalny styl w architekturze i zdobnictwie. Styl zakopiański został zaadaptowany przez kolejne pokolenia Podhalan, którzy nadal uznają go za własny; co więcej, do dziś stanowi wzorzec dla architektów i projektantów. W nowych realizacjach w Zakopanem można zaobserwować rozmaite formy budynków – twórcze interpretacje stylu, realizacje kontrowersyjne albo powierzchownie nawiązujące do tradycji. Długie trwanie idei Witkiewicza wpisuje się w kulturową kategorię „tradycji wynalezionej”, rozumianej procesualnie, podlegającej przekształceniom i reinterpretacji.]]>
<![CDATA[Podstawowe własności mechaniczne stali S.A. 387 Gr.11 Cl.2 w podwyższonej temperaturze]]> Wed, 13 Oct 2021 11:16:59 +0200 Stankiewicz, Marek; Baran, Marek; Stępień, Tadeusz
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<![CDATA[Hierarchical FeCo/C@Ni(OH)2 heterostructures for enhanced oxygen evolution activity]]> Wed, 13 Oct 2021 10:19:54 +0200 Xie, Cong; Zhang, Xiao; Matras-Postolek, Katarzyna; Yang, Ping
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Abstrakt: Layered Ni(OH)2 nanosheets are considered as one of the most promising oxide evolution reaction (OER) catalysts due to its excellent oxidation and reduction reaction performance which has been extensively studied. However, there is a big gap between the Ni(OH)2 nanosheets and noble metal catalysts in terms of the OER activity which is difficult to meet the request of application. Here, a strategy was developed to deposit Ni(OH)2 nanosheets on FeCo/C nanocubes surface to create a hierarchical heterostructure as a new type of non-noble metal catalyst. The initial overpotential of the prepared FeCo/C@Ni(OH)2 catalyst is as low as 212 mV and the Tafel slope is smaller compared with the precursor materials. The composite materials revealed enhanced cycle stability which can maintain more than 90% of initial current density after running for 10 h under 100 mV overpotential. The improvement of OER activity is ascribed to the FeCo/C nanocubes, which can not only improve the charge transport of the material, but also prevent the agglomeration of Ni(OH)2 nanosheets. The exciting features of FeCo/C@Ni(OH)2 nanocomposite open up the possibilities of preparing efficient and stable non-noble metal catalysts for OER electrocatalysts.]]>
<![CDATA[Validation of a 1:8 scale measurement stand for testing airborne sound insulation]]> Wed, 13 Oct 2021 08:27:22 +0200 Szeląg, Agata; Baruch‐Mazur, Katarzyna; Brawata, Krzysztof; Przysucha, Bartosz; Mleczko, Dominik
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Abstrakt: This paper contains a detailed description of the design and validation of a measurement stand for testing the airborne sound insulation of specimens made at a small scale. The stand is comprised of two coupled reverberation rooms in which the geometry represents the full‐size reverberation rooms used at the AGH University of Science and Technology at a 1:8 scale. The paper proves that both the scaled measurement stand and the testing methodology conform to the ISO 10140 standards, and that the obtained measurement uncertainty does not exceed the maximum values specified in ISO 12999‐1. Moreover, the calculated uncertainty of measurements obtained for the 1:8 scale stand is comparable with the typical uncertainty given in ISO 12999‐1 and the uncertainty obtained on the full‐scale measurement stand. In connection with the above, the authors have proved that by using the scaled‐down measurement stands, one can obtain reliable and repeatable results of measurements of airborne sound insulation.]]>
<![CDATA[Smartphone-based human sitting behaviors recognition using inertial sensor]]> Wed, 13 Oct 2021 08:24:49 +0200 Kumar Sinha, Vikas; Kumar Patro, Kiran; Pławiak, Paweł; Jaya Prakash, Allam
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Abstrakt: At present, people spend most of their time in passive rather than active mode. Sitting with computers for a long time may lead to unhealthy conditions like shoulder pain, numbness, headache, etc. To overcome this problem, human posture should be changed for particular intervals of time. This paper deals with using an inertial sensor built in the smartphone and can be used to overcome the unhealthy human sitting behaviors (HSBs) of the office worker. To monitor, six volunteers are considered within the age band of 26 ± 3 years, out of which four were male and two were female. Here, the inertial sensor is attached to the rear upper trunk of the body, and a dataset is generated for five different activities performed by the subjects while sitting in the chair in the office. Correlation-based feature selection (CFS) technique and particle swarm optimization (PSO) methods are jointly used to select feature vectors. The optimized features are fed to machine learning supervised classifiers such as naive Bayes, SVM, and KNN for recognition. Finally, the SVM classifier achieved 99.90% overall accuracy for different human sitting behaviors using an accelerometer, gyroscope, and magnetometer sensors.]]>
<![CDATA[In search of effective UiO-66 metal-organic frameworks for artificial kidney application]]> Wed, 13 Oct 2021 08:21:39 +0200 Dymek, Klaudia; Kurowski, Grzegorz; Kuterasiński, Łukasz; Jędrzejczyk, Roman; Szumera, Magdalena; Sitarz, Maciej; Pajdak, Anna; Kurach, Łukasz; Boguszewska-Czubara, Anna; Jodłowski, Przemysław J.
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Abstrakt: The removal of uremic toxins from patients with acute kidney injury is a key issue in improving the quality of life for people requiring peritoneal dialysis. The currently utilized method for the removal of uremic toxins from the human organism is hemodialysis, performed on semipermeable membranes where the uremic toxins, along with small molecules, are separated from proteins and blood cells. In this study, we describe a mixed-linker modulated synthesis of zirconium-based metal–organic frameworks for efficient removal of uremic toxins. We determined that the efficient adsorption of uremic toxins is achieved by optimizing the ratio between −amino functionalization of the UiO-66 structure with 75% of −NH2 groups within organic linker structure. The maximum adsorption of hippuric acid and 3-indoloacetic acid was achieved by UiO-66-NH2 (75%) and by UiO-66-NH2 (75%) 12.5% HCl prepared by modulated synthesis. Furthermore, UiO-66-NH2 (75%) almost completely adsorbs 3-indoloacetic acid bound to bovine serum albumin, which was used as a model protein to which uremic toxins bind in the human body. The high adsorption capacity was confirmed in recyclability test, which showed almost 80% removal of 3-indoloacetic acid after the third adsorption cycle. Furthermore, in vitro cytotoxicity tests as well as hemolytic activity assay have proven that the UiO-66-based materials can be considered as potentially safe for hemodialytic purposes in living organisms.]]>
<![CDATA[Przyczyny pękania rur ze stali X20CrMoV121 podczas gięcia na zimno]]> Wed, 13 Oct 2021 08:18:18 +0200 Mazur, Marek; Stankiewicz, Marek
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<![CDATA[Mn:CsPbBr3 nanoplatelets for bright white-emitting displays]]> Tue, 12 Oct 2021 11:54:14 +0200 Zhao, Yubin; Xie, Cong; Zhang, Xiao; Matras-Postolek, Katarzyna; Yang, Ping
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Abstrakt: Controlled ion-exchange reactions endow CsPbX3 nanocrystals (NCs) with superior photoluminescence (PL) properties. In this study, MnX2 (X = Cl and Br) was used as the precursor of Mn for cation-exchange reactions to synthesize Mn-doped CsPbBr3 nanoplatelets (NPLs). The anion-derived cation-exchange reactions occur within a short period of time. The PL peaks of CsPbBr3 NPLs were adjusted from 460 to 500 nm (redshift) by controlling the thickness of NPLs. The ion-exchange process of MnBr2 and CsPbBr3 NPLs resulted in Mn doping because of the PL peak (∼610 nm) of Mn ions observed. With increasing MnBr2 incorporation, CsPbBr3 NPLs excited d-d transfer from Mn ions, resulting in an increased PL intensity of Mn ions. Two PL peaks from CsPbBr3 NPLs and Mn ions were obtained, in which the PL color of Mn:CsPbBr3 composites changed from blue to white. The PL quantum yield (PLQYs) of Mn:CsPbBr3 composites is up to 64.4%. Br ion-derived ion exchange plays an important role for Mn ions that enter the crystal lattices instead of Pb NPLs. After ion exchange, the morphology of the sample remained unchanged. However, the PLQYs of the sample increased. The average lifetimes of the sample depended strongly on the emission wavelength. With the increasing amount of Mn doping, the lifetime was increased to 1.63 ms (λem = 610 nm) from the ns level. A white-emitting sample with the Commission Internationale de I′Eclairage (CIE) coordinates of 0.3013 and 0.3089, as well as PLQYs of 95% were obtained by adding green-emitting CsPbBr3 nanocrystals in Mn:CsPbBr3 NPLs, suggesting an important application in displaying devices.]]>
<![CDATA[Mesoporous silica-coated CsPbX3 nanocrystals with high stability and ion-exchange resistance for bright white-emitting displays]]> Tue, 12 Oct 2021 11:28:33 +0200 Shi, Wenbin; Zhang, Xiao; Matras-Postolek, Katarzyna; Yang, Ping
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Abstrakt: All-inorganic metal halide perovskite (CsPbX3) nanocrystals (NCs) have attracted much attention due to their excellent photoelectric properties. However, CsPbX3 NCs are easily affected by polar solvents because of their ionic crystal nature, which led to luminescence quenching. In this paper, mesoporous silica nanoparticles (MSNs) were used as carriers to anchor CsPbX3 NCs for effectively improving the resistance of CsPbX3 NCs in polar solvents. CsPbX3@MSN composites were created via a sol–gel-assisted ligand exchanging process. The photoluminescence (PL) intensity of the CsPbX3@MSNs composite still maintained more than 50% of their initial value after 60 min of treatment with water and ethanol. The mesoporous structures of SiO2 spheres facilitate efficient coupling of CsPbX3 NCs to improve the stability and decrease surface defects, resulting in high PL quantum yield. CsPbX3@MSN composites have unique advantages for white-light-emitting diodes (LEDs) as solid-state luminescent materials. White LED devices were fabricated using CsPbX3@MSN composites as the solid-state light-emitting conversion layer. The color temperature was 6838 K, and the luminous efficiency was 8.9 lm/W. Its coincidence degree with the gamut space specified by NTSC 1953 is 135%, and the coincidence degree with the gamut space specified by ITU-R B.T. 2020 (Rec. 2020) is 95%.]]>
<![CDATA[A matrix FMEA analysis of variable delivery vane pumps]]> Tue, 12 Oct 2021 10:46:30 +0200 Fabiś-Domagała, Joanna; Domagała, Mariusz; Momeni, Hassan
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Abstrakt: Hydraulic systems are widely used in the aeronautic, machinery, and energy industries. The functions that these systems perform require high reliability, which can be achieved by examining the causes of possible defects and failures and by taking appropriate preventative measures. One of the most popular methods used to achieve this goal is FMEA (Failure Modes and Effects Analysis), the foundations of which were developed and implemented in the early 1950s. It was systematized in the following years and practically implemented. It has also been standardized and implemented as one of the methods of the International Organization for Standardization (ISO) 9000 series standards on quality assurance and management. Apart from wide application, FMEA has a number of weaknesses, which undoubtedly include risk analysis based on the RPN (Risk Priority Number), which is evaluated as a product of severity, occurrence, and detection. In recent years, the risk analysis has been very often replaced by fuzzy logic. This study proposes the use of matrix analysis and statistical methods for performing simplified RCA (Root Cause Analysis) and for classification potential failures for a variable delivery vane pump. The presented methodology is an extension of matrix FMEA and allows for prioritizing potential failures and their causes in relation to functions performed by pump components, the end effects, and the defined symptoms of failure of the vane pump.]]>
<![CDATA[Modelling of cnditional scalar dissipation rate in turbulent premixed combustion]]> Tue, 12 Oct 2021 10:42:45 +0200 Amzin, Shokri; Domagała, Mariusz
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Abstrakt: In turbulent premixed flames, for the mixing at a molecular level of reactants and products on the flame surface, it is crucial to sustain the combustion. This mixing phenomenon is featured by the scalar dissipation rate, which may be broadly defined as the rate of micro-mixing at small scales. This term, which appears in many turbulent combustion methods, includes the Conditional Moment Closure (CMC) and the Probability Density Function (PDF), requires an accurate model. In this study, a mathematical closure for the conditional mean scalar dissipation rate, , in Reynolds, Averaged Navier–Stokes (RANS) context is proposed and tested against two different Direct Numerical Simulation (DNS) databases having different thermochemical and turbulence conditions. These databases consist of lean turbulent premixed V-flames of the CH4-air mixture and stoichiometric turbulent premixed flames of H2-air. The mathematical model has successfully predicted the peak and the typical profile of with the sample space ζ and its prediction was consistent with an earlier study.]]>
<![CDATA[Historical analysis of the example of Nowy Sącz in space syntax perspective. Guidelines for future development of urban matrix in medium-sized cities]]> Mon, 11 Oct 2021 17:36:41 +0200 Suchoń, Filip; Olesiak, Justyna
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Abstrakt: This paper presents the development of the public space of Nowy Sącz, taking into account the space syntax analysis of the historical maps of the city and the structure of its development. Nowy Sącz is a city located in southern Poland, with over 80,000 residents. A space syntax analysis of historical maps helps to explain the urban space’s growth and development structure. The scientific goal of this paper was to build model solutions and urban typologies of Nowy Sącz; to present the logic of the model; and to compare simulation results with reality and historical knowledge. The application goal was to explain the processes and popularize the insight using clear space syntax visualizations. Axial maps of street networks were developed using current and historical city plans (publicly available plans from the late 18th century to the present day). The space syntax methodology was employed to measure Integration and Choice variables for each stage of the city’s spatial development. The results indicating areas of the highest Integration value were verified against historical studies. A strong correlation was demonstrated between the foci of urban life of super-local reach and their places in a growing city’s structural network.]]>
<![CDATA[A concept of risk prioritization in FMEA analysis for fluid power systems]]> Mon, 11 Oct 2021 14:33:47 +0200 Fabiś-Domagała, Joanna; Domagała, Mariusz; Momeni, Hassan
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Abstrakt: FMEA analysis is a tool of quality improvement that has been widely used for decades. Its classical version prioritizes risk of failure by risk priority number (RPN). The RPN is a product of severity (S), occurrence (O), and detection (D), where all of the factors have equal levels of significance. This assumption is one of the most commonly criticized drawbacks, as it has given unreasonable results for real-world applications. The RPN can produce equal values for combinations of risk factors with different risk implications. Another issue is that of the uncertainties and subjectivities of information employed in FMEA analysis that may arise from lack of knowledge, experience, and employed linguistic terms. Many alternatives of risk assessment methods have been proposed to overcome the weaknesses of classical FMEA risk management in which we can distinguish methods of modification of RPN numbers of employing new tools. In this study, we propose a modification of the traditional RPN number. The main difference is that severity and occurrence are valued based on subfactors. The detection number remained unchanged. Additionally, the proposed method prioritizes risk in terms of implied risk to the systems by implementing functional failures (effects of potential failures). A typical fluid power system was used to illustrate the application of this method. The method showed the correct failure classification, which meets the industrial experience and other research results of failures of fluid power systems.]]>
<![CDATA[Electron beam-treated enzymatically mineralized gelatin hydrogels for bone tissue engineering]]> Mon, 11 Oct 2021 12:30:37 +0200 Riedel, Stefanie; Mazur, Karolina
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Abstrakt: Biological hydrogels are highly promising materials for bone tissue engineering (BTE) due to their high biocompatibility and biomimetic characteristics. However, for advanced and customized BTE, precise tools for material stabilization and tuning material properties are desired while optimal mineralisation must be ensured. Therefore, reagent-free crosslinking techniques such as high energy electron beam treatment promise effective material modifications without formation of cytotoxic by-products. In the case of the hydrogel gelatin, electron beam crosslinking further induces thermal stability enabling biomedical application at physiological temperatures. In the case of enzymatic mineralisation, induced by Alkaline Phosphatase (ALP) and mediated by Calcium Glycerophosphate (CaGP), it is necessary to investigate if electron beam treatment before mineralisation has an influence on the enzymatic activity and thus affects the mineralisation process. The presented study investigates electron beam-treated gelatin hydrogels with previously incorporated ALP and successive mineralisation via incubation in a medium containing CaGP. It could be shown that electron beam treatment optimally maintains enzymatic activity of ALP which allows mineralisation. Furthermore, the precise tuning of material properties such as increasing compressive modulus is possible. This study characterizes the mineralised hydrogels in terms of mineral formation and demonstrates the formation of CaP in dependence of ALP concentration and electron dose. Furthermore, investigations of uniaxial compression stability indicate increased compression moduli for mineralised electron beam-treated gelatin hydrogels. In summary, electron beam-treated mineralized gelatin hydrogels reveal good cytocompatibility for MG-63 osteoblast like cells indicating a high potential for BTE applications.]]>
<![CDATA[The potential of Λ and Ξ− studies with PANDA at FAIR]]> Sat, 09 Oct 2021 09:46:28 +0200 Barucca, G.; Domagała, M.; Filo, G.; Lisowski, E.; Lisowski, F.; Michałek, M.; Poznański, P.; Płażek, J.
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Abstrakt: The antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in terms of scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss ground-state hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels: p¯ p→ Λ¯ Λ and p¯ p→ Ξ¯ +Ξ-. The results, presented in detail in this paper, show that hyperon-antihyperon pairs from these reactions can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA. © 2021, The Author(s).]]>
<![CDATA[Study of excited Ξ baryons with the PANDA detector]]> Sat, 09 Oct 2021 09:42:00 +0200 Barucca, G.; Domagała, M.; Filo, G.; Lisowski, E.; Lisowski, F.; Michałek, M.; Poznański, P.; Płażek, J.
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Abstrakt: The study of baryon excitation spectra provides insight into the inner structure of baryons. So far, most of the world-wide efforts have been directed towards N * and Delta spectroscopy. Nevertheless, the study of the double and triple strange baryon spectrum provides independent information to the N * and Delta spectra. The future antiproton experiment (P) over bar ANDA will provide direct access to final states containing a (Xi) over bar Xi pair, for which production cross sections up to mu b are expected in (p) over barp reactions. With a luminosity of L = 10(31) cm(-2) s(-1) in the first phase of the experiment, the expected cross sections correspond to a production rate of similar to 10(6) events/day. With a nearly 4 pi detector acceptance, (P) over bar ANDA will thus be a hyperon factory. In this study, reactions of the type (p) over barp -> (Xi) over bar (+)Xi*(-) as well as (p) over barp -> (Xi) over bar*(+)Xi(-) with various decay modes are investigated. For the exclusive reconstruction of the signal events a full decay tree fit is used, resulting in reconstruction efficiencies between 3 and 5%. This allows high statistics data to be collected within a few weeks of data taking.]]>
<![CDATA[PANDA phase one. Panda colaboration.]]> Sat, 09 Oct 2021 09:38:00 +0200 Barucca, G.; Domagała, M.; Filo, G.; Lisowski, E.; Lisowski, F.; Michałek, M.; Poznański, P.; Płażek, J.
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Abstrakt: The Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany, provides unique possibilities for a new generation of hadron-, nuclear- and atomic physics experiments. The future antiProton ANnihilations at DArmstadt (PANDA or PANDA) experiment at FAIR will offer a broad physics programme, covering different aspects of the strong interaction. Understanding the latter in the nonperturbative regime remains one of the greatest challenges in contemporary physics. The antiproton–nucleon interaction studied with PANDA provides crucial tests in this area. Furthermore, the high-intensity, low-energy domain of PANDA allows for searches for physics beyond the Standard Model, e.g. through high precision symmetry tests. This paper takes into account a staged approach for the detector setup and for the delivered luminosity from the accelerator. The available detector setup at the time of the delivery of the first antiproton beams in the HESR storage ring is referred to as the Phase One setup. The physics programme that is achievable during Phase One is outlined in this paper.]]>
<![CDATA[Developing a framework to predict factors significant for creative architectural design performance of freshmen and senior architecture students, by adopting and validating the CEDA]]> Sat, 09 Oct 2021 07:39:57 +0200 Avsec, Stanislav; Jagiełło-Kowalczyk, Magdalena
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Abstrakt: This study aims to provide a framework to predict factors significant for creative engineering design performance of freshmen and senior architecture students. Since different environments demand utilisation of a rather interdisciplinary approach of design-cognition types of teaching and learning, an advanced model of creative engineering design process has been proposed to measure multifaceted effects of the architecture study programme. For the study, 108 freshmen and 98 senior architecture students were surveyed for attitudes towards engineering, proactivity, situational interest, perception of learning, and satisfaction with design work environment and tested for creative engineering design on fluency, flexibility, originality and usefulness of designs or solutions generated. Two models were developed based on social cognition supported by self-determination theory using predictive modelling. Results demonstrate that for freshmen creative design work is not well explained by the social-cognitive theory model, while for their senior counterparts the same is strongly explained. Student proactivity was a crucial predictor in perception of control over learning solution-based creative design work, especially in senior students. As the strongest negative predictor, tediousness toward engineering was identified in social-cognitive learning, pointing to the importance of engineering knowledge, beliefs, opinions, emotions, and responses towards wider definition of technology and engineering. Such students more likely do not utilise potential of technology and engineering to work on problem- and solution-driven design tasks to develop creativity. The findings are of particular interest for architecture education curriculum designers, design course conductors and different organisations to provide sustainable, creative and market-competitive design solutions.]]>
<![CDATA[Architektura łemkowska na Sądecczyźnie. Wczoraj i dziś, jutro?]]> Fri, 08 Oct 2021 09:47:33 +0200 Olesiak, Justyna
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Abstrakt: Odrębność i niepowtarzalna tożsamość mają równie duże znaczenie, jak artystyczne i historyczne walory dziedzictwa kulturowego. Odniesienia nowych dzieł do lokalnej tradycji architektonicznej, jak i poszukiwanie nowych środków wyrazu, w powiązaniu z historycznym, regionalnym budownictwem, mieszczą się w szeroko pojętym rozumieniu zrównoważonego rozwoju. Otwarta pozostaje kwestia, czy specyficzna, lokalna tradycja budownictwa łemkowskiego jest nadal czytelna, mimo zerwania kulturowej ciągłości i wobec cywilizacyjnych przemian terenów wiejskich. W oparciu o dotychczasowy stan badań i literaturę przedmiotu, przeprowadzono próbę rozeznania zasobu obiektów zachowanych, reliktów oraz przebudów w jednej z podsądeckich miejscowości. O ile obiekty sakralne są i były objęte ochroną i opieką, o tyle obiekty mieszkalne i gospodarcze stopniowo traciły swój odrębny charakter, ustępując miejsca nowej zabudowie. Tymczasem wiele prawideł, według których kształtowano tradycyjne budynki, znajduje obecnie odzwierciedlenie w wymogach współczesnej architektury energooszczędnej i przyjaznej środowisku. Powrót do tradycji stanowić może zatem - paradoksalnie - wyjście na spotkanie przyszłości.]]>
<![CDATA[Zespół ufortyfikowanych strażnic kolejowych w Kamionce Wielkiej]]> Fri, 08 Oct 2021 09:36:49 +0200 Suchoń, Filip; Olesiak, Justyna
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Abstrakt: Otwarta w 1876 roku linia kolejowa Tarnów–Leluchów–Orłów miała znaczenie głównie strategiczne. Tunele znajdujące się na tej linii zostały na początku XX wieku zabezpieczone ufortyfikowanymi strażnicami. Głównym celem badań było ustalenie pierwotnego wyglądu i sposobu funkcjonowania ufortyfikowanych strażnic przy tunelu w Kamionce Wielkiej (w powiecie nowosądeckim) oraz zarysowanie problemu odchodzącego w niepamięć, lokalnego dziedzictwa architektury militarnej. Zastosowano metody badawcze charakterystyczne dla tego rodzaju opracowania — kwerendę, analizę in situ, opis zebranych materiałów, ich uporządkowanie zgodnie z założonymi kryteriami, wsparcie materiałem graficznym. Materiał źródłowy, oprócz badań terenowych, stanowi archiwalna dokumentacja projektowa, archiwalne normy budowlane wraz z wytycznymi projektowymi, oraz publikacje teoretyczne z epoki. Opisano założenia koncepcyjne, historyczne projekty i realizacje podobnych obiektów na terenie dawnej monarchii austro-węgierskiej. Omówiony został zarówno zachowany do dnia dzisiejszego (2019) zasób w Małopolsce i na Podkarpaciu, jak i zasady architektonicznego kształtowania formy obiektów wobec wymogów specyficznej funkcji, jaką miały spełniać. Poddano analizie aspekty różnego traktowania podobnej spuścizny materialnej i kulturowej przez grona profesjonalne, a także ich społeczny, powszechny odbiór.]]>
<![CDATA[2D layered g-C3N4/WO3/WS2 S-scheme heterojunctions with enhanced photochemical performance]]> Fri, 08 Oct 2021 09:28:57 +0200 Song, Tong; Xie, Cong; Matras-Postolek, Katarzyna; Yang, Ping
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Abstrakt: Graphitic carbon nitride (g-C3N4)/WO3/WS2 ternary heterojunctions were fabricated for the first time via in situ growing WO3 and WS2 on superior thin g-C3N4 nanosheets. A mechanic chemical prereaction plays an important role in the formation of S-scheme heterojunctions. Namely, the heterostructured photocatalyst prepared by optimized preparation conditions revealed enhanced photodegrading activity (∼8.6 times of pure g-C3N4) for organic pollutants in the visible light region. Compared with g-C3N4 nanosheets, the rate of hydrogen generation increased to ∼7.8 times higher, in which the apparent quantum efficiency at 420 nm reached 8.9%. Particularly, the as-prepared ternary photocatalyst exhibited a hydrogen generation rate of 29 μmol g–1 h–1 even without Pt loaded. The matched energy band structure, band bending effect, and intimate interface contact of the 2D/2D g-C3N4/WO3 heterojunction together determined the S-scheme electron transfer path. Photogenerated electrons and holes with high redox capacities were reserved to participate in the photocatalytic process. In addition, the oxygen vacancies and WS2 improved light response and further promoted the separation of charge carriers. This result offered a new idea for the construction of metal-free photocatalysts to be applied in the photochemistry field.]]>
<![CDATA[Photodegradation process of organic dyes in the presence of a manganese-doped zinc sulfide nanowire photocatalyst]]> Fri, 08 Oct 2021 08:08:26 +0200 Żaba, Adam; Sovinska, Svitlana; Kirish, Tetiana; Węgrzynowicz, Adam; Matras-Postołek, Katarzyna
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Abstrakt: Zinc sulfide (ZnS) nanowires represent a promising candidate in many fields, including optoelectronics and photocatalysis because of their advantages such as excellent optical properties, chemical stability and an easy-scalable simple synthesis method. In this study, an energy-friendly microwave radiation process was used to develop the single-step, solvothermal process for the growth of manganese-doped zinc sulfide (ZnS) and undoped nanocrystals (NCs) in the forms of nanowires using two short amines as a stabilizer, e.g., ethylenediamine and hydrazine, respectively. ZnS nanowires doped with Mn atoms show absorbance in UV and in the visible region of the spectrum. The photocatalytic degradation of rhodamine B in the presence of Mn-doped and undoped ZnS nanocrystals illuminated with only a 6-W UV lamp has been comprehensively studied. The effect of Mn doping and the presence of a nanocrystal stabilizer on the degradation process was determined. It was found that the efficiency of a photocatalytic degradation process was strongly affected by both factors: the doping process of nanowires with Mn2+ atoms and the attachment of ligands to the nanocrystal surface.]]>
<![CDATA[Effects of neglecting PCM hysteresis while making simulation calculations of a building located in polish climatic conditions]]> Fri, 08 Oct 2021 07:56:25 +0200 Zastawna-Rumin, Anna; Nowak, Katarzyna
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Abstrakt: The use of phase change materials (PCM) in different building applications is a hot topic in today’s research and development activities. Numerous experimental tests confirmed that the hysteresis of the phase change process has a noticeable effect on heat accumulation in PCM. The authors are trying to answer the question of whether the neglecting of hysteresis or the impact of the speed of phase transformation processes reduce the accuracy of the simulation. The analysis was performed for a model building, created to validate the energy calculations. It was also important to conduct simulations for the polish climatic conditions. The calculations were conducted for three variants of materials. In addition, in the case of models containing layers with PCM, calculations were made both taking into account, as well as excluding material hysteresis in the calculations. In the analyzed examples, after taking into account hysteresis in the calculations, the period of time when surface temperature is below the phase change temperature of the materials decreased by 10.6% and 29.4% between 01 June to 30 September, for the options with PCM boards and Dupont boards, respectively. Significant differences in surface temperature were also observed. The effects of neglecting, even relatively small hysteresis, in the calculations are noticeable and can lead to significant errors in the calculation.]]>
<![CDATA[Multifrequency impedance tomography system for research on environmental and thermal processes]]> Fri, 08 Oct 2021 07:53:04 +0200 Porzuczek, Jan
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Abstrakt: The possibility for spatial and temporal monitoring of environmental, chemical or thermal processes is of high importance for their better understanding thus control and optimization. Therefore, measurement methods that enable such opportunities might be especially valuable for researchers and process engineers. For this reason, in this paper the novel Electrical Impedance Tomography system is proposed that enables the visualization of the processes in which the electrical conductivity of material is changing. The proposed EIT system is based mostly on general purpose equipment. It consists of three laboratory-grade devices: a signal generator, a switching device and a data acquisition card for voltage measurement. In addition to those devices, the current source was constructed to complete the system. The EIT system was designed to have the ability of sourcing the current of frequency up to 250 kHz. A set of validation experiments were carried out to verify the EIT system accuracy. The validation tests consisted of object detection, distinguishing between objects of different conductivity, multifrequency imaging and visualization of slow-changing processes. The obtained results were also compared with the numerical simulations. The proposed system was proven to have the ability of correct imaging of irregularity inside the area of the sensor.]]>
<![CDATA[Eksperymentalny dom prefabrykowany w systemie OWT w Krakowie – Kurdwanowie. Studium przypadku]]> Fri, 08 Oct 2021 07:49:57 +0200 Woźniczka, Magdalena
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Abstrakt: Publikacja to studium przypadku, jaki stanowi prefabrykowany dom jednorodzinny w technologii OWT/65 wzniesiony w Krakowie – Kurdwanowie w latach 1984–1988. Celem jest ukazanie, jak budowa i eksploatacja domu jednorodzinnego w systemie OWT spełniła zamierzenia oraz nadzieje projektantów. Metodami badań były analizy: systemu OWT, koncepcji domów prefabrykowanych w systemie OWT opracowanych przez Martę i Krzysztofa Woźniczkę w roku 1983, dokumentacji fotograficznej, projektów budowy i przebudowy badanego domu; oraz wywiad z Martą i Krzysztofem Woźniczką. W rezultacie badań określono, że dom w systemie OWT częściowo spełnił pokładane w nim nadzieje. Koszt jego wybudowania był niski, a stworzona forma i układ przestrzenny mogły być dostosowywane do zmieniających się potrzeb mieszkańców. Wadami koncepcji okazała się konieczność wykonania wielu, pierwotnie nieplanowanych, prac, które wydłużyły proces budowy i zwiększyły koszty realizacji. Niemniej badany dom mimo upływu lat dobrze spełnia swoją funkcję. Jest to zasługa możliwości modernizacji i dostosowywania obiektu do bieżących potrzeb.]]>
<![CDATA[Wpływ Ogólnych Planów Zagospodarowania Przestrzennego miasta Krakowa obowiązujących w latach 1967–2003 na zagospodarowanie przestrzeni Kurdwanowa]]> Fri, 08 Oct 2021 07:45:32 +0200 Woźniczka, Magdalena
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Abstrakt: Celem zaprezentowanych w artykule badań jest określenie wpływu Ogólnych Planów Zagospodarowania Przestrzennego (OPZP) miasta Krakowa na obszar Kurdwanowa. Zasadniczą metodą badań była analiza OPZP uchwalonych w latach 1967–1994 oraz zdjęć lotniczych i ortofotomap. W rezultacie przeprowadzonej analizy opracowano schematy graficzne zagospodarowania przestrzeni (wg OPZP i zagospodarowania rzeczywistego) oraz zestawienia tabelaryczne. W ta-belach zostały przedstawione wybrane funkcje obszarów (wg OPZP i stanu rzeczywistego) ze wskazaniem powierzchni oraz udziału procentowego w ogólnej powierzchni Kurdwanowa, a także stan realizacji założeń OPZP. W wyniku przeprowadzonych badań wykazano, że zagospodarowanie przestrzeni Kurdwanowa zostało ukształtowane na bazie ustaleń OPZP.]]>
<![CDATA[Identification of buried historical mineshaft using ground-penetrating radar]]> Thu, 07 Oct 2021 18:24:38 +0200 Pilecki, Zenon; Krawiec, Krzysztof; Pilecka, Elżbieta; Kotyrba, Andrzej; Tomecka-Suchoń, Sylwia; Łątka, Tomasz
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Abstrakt: Buried historical mineshafts constitute significant sinkhole hazards and sources of geotechnical risks. The locations of buried mineshafts on old mining maps are prone to inaccuracies. An efficient way to limit these inaccuracies is to use geophysical methods. However, their effectiveness strongly depends on the local survey conditions. The aim of the study was to identify the buried 14th century Wielki mineshaft in Bochnia Salt Mine, a UNESCO Worldwide Heritage Site, Poland. The need to locate this shaft was due to the following reasons. Firstly, the Bochnia Salt Mine had difficulties with water flowing into the workings from the supposed location of the Wielki mineshaft. The shaft area was one of the most waterlogged in the salt mine's terrain. An urgent task was to determine the shaft's exact location to implement a waterproof barrier to protect the historic mine workings. Secondly, the modernisation of the market square in Bochnia required clarification of the location of the Wielki mineshaft and checking as to whether it posed a sinkhole hazard to the terrain surface. Another important reason for locating the medieval shaft was its archaeological value. A ground surface and borehole ground-penetrating radar (GPR) study and geological-engineering recognition using boreholes were employed to indicate the location of the Wielki shaft. The anthropogenic layer of heterogeneous material and the urbanised site resulted in challenges with regard to detecting evident georadar anomalies. Several dozen intersecting GPR profiles were gathered in the research area using 250 MHz and 100 MHz antennae. The initial surface GPR results, indicative of the GPR anomaly, were consolidated by cored borehole investigation and a borehole GPR study. In particular, the presence of a void, loosened zones, and wooden fragments of the shaft lining was confirmed in the inclined control borehole. Following our classification of typical causes of the occurrence of sinkholes over buried mineshafts, the consolidation of backfill material in a mineshaft was determined as the cause of the sinkhole originated above the Wielki shaft (type B sinkhole). Destruction of the shaft's wooden cap may result in the occurrence of a sinkhole on the ground surface. Therefore, the void was backfilled and a hydraulic barrier was consequently made to stop the seepage of water into the Bochnia Salt Mine's historic workings. This case study demonstrates that surface and borehole GPR surveying integrated with borehole data offers the possibility of obtaining the high-resolution data needed to accurately locate an old buried mineshaft in an urbanised area. The GPR anomaly was indirectly detected on the basis of the deflection of the boundary between the natural ground and an anthropogenic layer with sufficient contrast in their electromagnetic properties. This approach can be useful wherever the georadar penetration range is limited by high attenuation and dispersiveness of the anthropogenic layer.]]>
<![CDATA[Application of advanced machine learning approaches to predict the compressive strength of concrete containing supplementary cementitious materials]]> Thu, 07 Oct 2021 14:19:34 +0200 Ahmad, Waqas; Ahmad, Ayaz; Ostrowski, Krzysztof Adam; Aslam, Fahid; Joyklad, Panuwat; Zajdel, Paulina
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Abstrakt: The casting and testing specimens for determining the mechanical properties of concrete is a time-consuming activity. This study employed supervised machine learning techniques, bagging, AdaBoost, gene expression programming, and decision tree to estimate the compressive strength of concrete containing supplementary cementitious materials (fly ash and blast furnace slag). The performance of the models was compared and assessed using the coefficient of determination (R2), mean absolute error, mean square error, and root mean square error. The performance of the model was further validated using the k-fold cross-validation approach. Compared to the other employed approaches, the bagging model was more effective in predicting results, with an R2 value of 0.92. A sensitivity analysis was also prepared to determine the level of contribution of each parameter utilized to run the models. The use of machine learning (ML) techniques to predict the mechanical properties of concrete will be beneficial to the field of civil engineering because it will save time, effort, and resources. The proposed techniques are efficient to forecast the strength properties of concrete containing supplementary cementitious materials (SCM) and pave the way towards the intelligent design of concrete elements and structures.]]>
<![CDATA[Prediction of geopolymer concrete compressive strength using novel machine learning algorithms]]> Thu, 07 Oct 2021 12:05:37 +0200 Ahmad, Ayaz; Ahmad, Waqas; Chaiyasarn, Krisada; Ostrowski, Krzysztof Adam; Aslam, Fahid; Zajdel, Paulina; Joyklad, Panuwat
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Abstrakt: The innovation of geopolymer concrete (GPC) plays a vital role not only in reducing the environmental threat but also as an exceptional material for sustainable development. The application of supervised machine learning (ML) algorithms to forecast the mechanical properties of concrete also has a significant role in developing the innovative environment in the field of civil engineering. This study was based on the use of the artificial neural network (ANN), boosting, and AdaBoost ML approaches, based on the python coding to predict the compressive strength (CS) of high calcium fly-ash-based GPC. The performance comparison of both the employed techniques in terms of prediction reveals that the ensemble ML approaches, AdaBoost, and boosting were more effective than the individual ML technique (ANN). The boosting indicates the highest value of R2 equals 0.96, and AdaBoost gives 0.93, while the ANN model was less accurate, indicating the coefficient of determination value equals 0.87. The lesser values of the errors, MAE, MSE, and RMSE of the boosting technique give 1.69 MPa, 4.16 MPa, and 2.04 MPa, respectively, indicating the high accuracy of the boosting algorithm. However, the statistical check of the errors (MAE, MSE, RMSE) and k-fold cross-validation method confirms the high precision of the boosting technique. In addition, the sensitivity analysis was also introduced to evaluate the contribution level of the input parameters towards the prediction of CS of GPC. The better accuracy can be achieved by incorporating other ensemble ML techniques such as AdaBoost, bagging, and gradient boosting.]]>
<![CDATA[Monitoring of large diameter sewage collector strengthened with glass-fiber reinforced plastic (GRP) panels by means of distributed fiber optic sensors (DFOS)]]> Thu, 07 Oct 2021 08:00:51 +0200 Popielski, Paweł; Bednarz, Bartosz; Sieńko, Rafał; Howiacki, Tomasz; Bednarski, Łukasz; Zaborski, Bartosz
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Abstrakt: Diagnostics and assessment of the structural performance of collectors and tunnels require multi-criteria as well as comprehensive analyses for improving the safety based on acquired measurement data. This paper presents the basic goals for a structural health monitoring system designed based on distributed fiber optic sensors (DFOS). The issue of selecting appropriate sensors enabling correct strain transfer is discussed hereafter, indicating both limitations of layered cables and advantages of sensors with monolithic cross-section design in terms of reliable measurements. The sensor’s design determines the operation of the entire monitoring system and the usefulness of the acquired data for the engineering interpretation. The measurements and results obtained due to monolithic DFOS sensors are described hereafter on the example of real engineering structure—the Burakowski concrete collector in Warsaw during its strengthening with glass-fiber reinforced plastic (GRP) panels.]]>
<![CDATA[Lockdown in a disneyfied city: Kraków Old Town and the first wave of the Covid-19 pandemic]]> Thu, 07 Oct 2021 07:57:29 +0200 Porębska, Anna; Barnaś, Krzysztof; Dendura, Bartosz; Kania, Olga; Łukasik, Marta; Rogulska, Aleksandra; Szpakowska-Loranc, Ernestyna; Zieliński, Miłosz
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Abstrakt: This paper presents the geography of the historic central district of Kraków, Poland before, during and after the first wave of the 2020 pandemic. It describes how the disneyfied main part of the UNESCO heritage site of universal values turned into a ghost town as functional changes were turning into physical ones amid restrictions. From the results of pre-pandemic processes (that, as we argue, turned the city into its disneyfied version), to the lockdown (that later revealed itself to be but the first one in a row), to the post-lockdown recovery, these changes are presented in modified figure-ground diagrams with accessibility being defined by both tangible and intangible properties. The results are set against the background of the city’s current policies regarding economic recovery, mobility and accessibility to urban green areas. As an attempt to address the present vulnerability of the once resilient historic city centres—of which Kraków Old Town is a luminous example—this paper tends to be a voice in the debate on the post-2020 planning and the strategies we will need to face the subsequent waves of this, or other, pandemics as well as consequences of climate change.]]>
<![CDATA[Problems in volumetric flow rate and liquid level control of a continuous stirred tank bioreactor with structured and unstructured kinetics]]> Thu, 07 Oct 2021 07:54:03 +0200 Bizon, Katarzyna; Tabiś, Bolesław
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Abstrakt: All equipment and devices utilized in various chemical and biochemical technologies are subject to external disturbances. In continuous flow systems, usually operating under steady-state conditions, these disturbances result in departure from the steady state. The paper reports on the process consequences of perturbations of the volumetric flow rate in a continuous stirred tank microbiological reactor, and on the automatic control of the liquid level by means of continuous P and PI controllers. The dynamics of the uncontrolled and controlled bioreactor were compared based on two kinetic models: an unstructured Haldane model and an one-parameter structured model. The paper investigates the effects of sudden step and oscillatory disturbances. It was shown that, for oscillatory variations in the feed rate, the biomass washout phenomenon depends on the period of oscillation, and occurs for oscillations with a sufficiently long period. This unfavorable phenomenon can be eliminated by applying liquid level control. Additionally, it was demonstrated that the use of a structured model gives a more reliable assessment of the dynamics of uncontrolled and controlled bioreactors subjected to step forcing. If the bioreactor is subjected to sinusoidal forcing, then the type of kinetic model used, i.e. structured or unstructured, made no difference.]]>
<![CDATA[Application of the hierarchy analysis method to assess interchanges in Cracow]]> Wed, 06 Oct 2021 09:54:02 +0200 Solecka, Katarzyna; Dumanowski, Łukasz; Taran, Igor; Litvinova, Yana
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Abstrakt: We propose an assessment methodology of interchanges, which is based on one of four multi-criteria decision aid method, the AHP method, allowing the ranking of interchanges from best to worst with regard to specific criteria. The selected criteria account for different evaluation aspects (social, technical, functional, environmental, and economic ones). The final ranking of the interchanges from best to worst allows making conclusions related to assessed elements of interchanges, which should be improved to make interchanges friendlier to the passengers. The proposed interchange assessment method allows the identification of the weakest elements of the assessed interchanges, which require improvement in order to make the interchanges friendlier for passengers, with a view to increasing the number of passengers and boosting passengers’ willingness to use the interchanges.]]>
<![CDATA[Type II dilemma zone at high-speed signalized intersections in Poland]]> Wed, 06 Oct 2021 09:46:41 +0200 Bąk, R.; Chodur, J.; Stamatiadis, N.
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Abstrakt: Red-light running at intersections is a common problem that may have severe consequences for traffic safety. The present paper investigates driver behavior in dilemma zones in Polish conditions. Based on the empirical research conducted at 25 urban and rural signalized intersections, type II dilemma zone boundaries were determined. In this study, generalized linear regression models were used to fit the probability of stopping to explanatory variables. Seeing as the dependent variable is dichotomous (stop/go), binary logistic regression was used for predicting the probability of the outcome based on the values of continuous or categorical predictor variables. The results show that factors which have a statistically significant effect on drivers’ propensity to stop include: vehicle type, the geometry of the intersection, location of signal heads, and platooning on the approach to the stop line. Type-II dilemma zone boundaries are situated at the following distance: the beginning from 1.9 s to 2.4 s, and end from 5.0 to 5.9 s (on average 2.2 ÷ 5.4 s) from the stop line.]]>
<![CDATA[Is it possible to obtain benefits by reducing the contribution of the digital signal processing techniques to the control of the active power filter?]]> Wed, 06 Oct 2021 09:29:42 +0200 Szromba, Andrzej
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Abstrakt: This paper presents a simple yet efficient control method for active power filters that can be used to improve power quality. Applying this method can open the way towards limiting the hard-ware and computational expenditure, which are needed for control of the active filter, while maintaining its required performance. The method is based on the indirect approach of obtain-ing reference signals combined with the closed-loop current control technique. Monitoring of changes of energy stored in reactance elements of the active filter is the base for obtaining ref-erence signals for compensation. The active filter can perform classical compensation and, addi-tionally, can perform some extra functionality for managing of active power in the system. In particular, it can stabilize the supplying source power, enable energy exchange between loads connected on DC and AC sides of the active filter, and—in a case of generating loads—enable their energy storage and redistribution amongst consuming loads. The presented method can be useful for voltage-source as current-source inverter based active filters, and for DC sys-tems as well as for AC single- or three-phase ones.]]>
<![CDATA[Pantograph sliding strips failure-reliability assessment and damage reduction method based on decision tree model]]> Tue, 05 Oct 2021 15:17:48 +0200 Kuźnar, Małgorzata; Lorenc, Augustyn; Kaczor, Grzegorz
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Abstrakt: Damage to the pantograph or sliding strip may cause the blocking of the railway line. This is the main reason for which the prediction of pantographs’ failure is important for railway carriers and researchers. This article presents a sliding strips failure prediction method as a main means of preventing disruptions to the transport chain. To develop the best predictive model based on the decision tree, the complex tree, medium tree and simple tree machine learning methods were tested. Using a decision tree, the categorization of the given technical conditions can be properly realized. The obtained results showed that the presented model can reduce sliding strip failure by up to 50%. Special attention was paid to the current collector (AKP-4E, 5ZL type), measured during periodic reviews of locomotives EU07 and EU09. To assess the reliability of the selected pantograph strips, a non-destructive degradation analysis was carried out. On the basis of the wear measurements of the strips and the critical value of wear, a failure distribution model was developed. Operational data, collected during periodic technical reviews, were provided by one of the biggest railway carriers in Poland. The results of the performed analyses may be used to build a preventive maintenance strategy to protect pantographs. The applied reliability models of wear propagation can be extended by the parameters of the cost and repair time becoming the basis for estimating the costs of operation and maintenance.]]>
<![CDATA[Development and characterization of lightweight geopolymer composite reinforced with hybrid carbon and steel]]> Tue, 05 Oct 2021 15:11:38 +0200 Baziak, Agnieszka; Pławecka, Kinga; Hager, Izabela; Castel, Arnaud; Korniejenko, Kinga
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Abstrakt: The aim of this paper is to analyze the influence of hybrid fiber reinforcement on the properties of a lightweight fly ash-based geopolymer. The matrix includes the ratio of fly ash and microspheres at 1:1. Carbon and steel fibers have been chosen due to their high mechanical properties as reinforcement. Short steel fibers (SFs) and/or carbon fibers (CFs) were used as reinforcement in the following proportions: 2.0% wt. CFs, 1.5% wt. CFs and 0.5% wt. SFs, 1.0% wt. CFs and 1.0% wt. SFs, 0.5% wt. CFs and 1.5% wt. SFs and 2.0% wt. SFs. Hybrid reinforcement of geopolymer composites was used to obtain optimal strength properties, i.e., compressive strength due to steel fiber and bending strength due to carbon fibers. Additionally, reference samples consisting of the geopolymer matrix material itself. After the production of geopolymer composites, their density was examined, and the structure (using scanning electron microscopy) and mechanical properties (i.e., bending and compressive strength) in relation to the type and amount of reinforcement. In addition, to determine the thermal insulation properties of the geopolymer matrix, its thermal conductivity coefficient was determined. The results show that the addition of fiber improved compressive and bending strength. The best compressive strength is obtained for a steel fiber-reinforced composite (2.0% wt.). The best bending strength is obtained for the hybrid reinforced composite: 1.5% wt. CFs and 0.5% wt. SFs. The geopolymer composite is characterized by low thermal conductivity (0.18–0.22 W/m ∙ K) at low density (0.89–0.93 g/cm3).]]>
<![CDATA[The variable frequency conductivity of geopolymers during the long aging period]]> Tue, 05 Oct 2021 12:36:59 +0200 Walter, Janusz; Uthayakumar, Marimuthu; Balamurugan, Ponnambalam; Mierzwiński, Dariusz
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Abstrakt: The variable frequency conductivity was applied to characterize the process of solidification of geopolymers based on fly ash with sand additives. XRD qualitative and quantitative analysis, porosity measurements, and sorption analysis of specific surface area were performed. The conductivity was correlated with porosity and specific surface area of geopolymer concretes. Both values of conductivity, real and imaginary parts, decreased during polymerization processing time. Characteristic maximum on graphs describing susceptance vs. frequency curve was observed. The frequency of this maximum depends on time of polymerization and ageing, and can also indicate porosity of material. Low-porous geopolymer concrete shows both low-conductivity values, and susceptance maximum frequency peak occurs more in the higher frequencies than in high-porous materials.]]>
<![CDATA[Scientific conservation of the outstanding theaters of the 19th century and their influence on the creation of modern art-space]]> Tue, 05 Oct 2021 12:33:32 +0200 Sandu, Ion; Orlenko, Mykola; Dyomin, Mykola; Ivashko, Oleksandr; Ivashko, Yulia; Lăzăreanu, Carmen Gabriela; Paprzyca, Krystyna; Sandu, Ioan Gabriel; Sztabińska-Kałowska, Paulina
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Abstrakt: The article analyses the specifics of the stylistics of the external and internal decoration of the outstanding theaters of Romania, Ukraine and Poland; defines the role of the Viennese school in this process; describes the problems of preserving these unique objects and describes the process of complex restoration of Odesa National Academic Theater of Opera and Ballet by specialists from the Ukrrestavratsiia Corporation. The scientific novelty of the research lies in the analysis of the construction processes of Odesa Theater of Opera and Ballet and the Municipal Theater (Teatr Miejski) in Cracow to prove the generality of trends in theatre construction in the second half of the 19th century; the replacement of wooden structures with various metal ones, and analysis of the principles of operation of the different types of metal structures. The reasons for the emergency state of theatres have been ascertained. The procedure for the conduct of the restoration measures and the effectiveness of their results was analyzed. The paper aims to emphasize the importance of the National Theater of Iasi as an element of cultural heritage and educational factor, in the context of other theaters built based on the projects of Viennese architects Fellner and Helmer. The National Theater of Iași is a real architectural jewel and a charming local party for its leisure visitors. This architectural monument houses a curtain of great beauty. The ceiling that is painted by Al. Goltz with pastel colors that represent paradisiacal allegories, being represented nymphs and angels, framed in the rococo structure. The Great Hall of the theater which has 740 seats and has a stable, lodges and balconies. This building was considered one of the most successful constructions.]]>
<![CDATA[Mechanical performance of timber connections made of thick flexible polyurethane adhesives]]> Tue, 05 Oct 2021 12:31:12 +0200 Pečnik, Jaka Gašper; Gavrić, Igor; Sebera, Václav; Kržan, Meta; Kwiecień, Arkadiusz; Zając, Bogusław; Azinović, Boris
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Abstrakt: This study investigates timber connections with flexible polyurethane adhesives, which prove to have the potential for timber-adhesive composite structures without mechanical connections for seismic regions. Results of conducted cyclic double lap-shear adhesive timber joints tests were compared with available experimental results on timber connections with standard mechanical dowel-type fasteners and with results of numerical finite element analysis. The study found that the shear strength, elastic stiffness and strength degradation capacity of the flexible adhesive connections were significantly higher compared to mechanical fasteners commonly used in seismic-resistant timber connections. The latter, however, manifested larger ultimate displacements but also yielded at lower displacements.]]>
<![CDATA[MoS2/CoS2 heterostructures embedded in N-doped carbon nanosheets towards enhanced hydrogen evolution reaction]]> Tue, 05 Oct 2021 11:50:57 +0200 Ji, Kang; Matras-Postolek, Katarzyna; Shi, Ruixia; Chen, Ling; Che, Quande; Wang, Junpeng; Yue, Yunlong; Yang, Ping
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Abstrakt: MoS2/CoS2 heterostructures on nitrogen-doped carbon nanosheets as an efficient electrocatalyst for hydrogen evolution reaction (HER) are prepared using zeolitic imidazolate frameworks-67 as precursors. Two dimensional (2D)/2D MoS2/CoS2 heterostructures consist of layered CoS2 and MoS2. The (210) facet of CoS2 and the (002) facet of MoS2 contacted vertically resulted in improved electrons and holes transfer in the interface. The ratios of CoS2/MoS2 plays an important role to get high performance (CoS2/MoS2/NC-n%, e.g. n = 20, 25, 30, 35 wt%). Meanwhile, sample CoS2/MoS2/NC-25% revealed the best HER activity, sug-gesting the sample has the largest number of active sites and the fastest electron transfer rate. In addition, sample CoS2/MoS2/NC-25% exhibited the lowest onset potential of 51 mV, the lowest potential of 215 mV at 10 mA cm−2, and the smallest Tafel slope of 80.0 mV dec−1. The result is utilizable for the construction of heterostructures with excellent HER performance.]]>
<![CDATA[Podłączenie grzejników: rozwiązania systemowe, zestawy podłączeniowe]]> Tue, 05 Oct 2021 11:48:23 +0200 Muniak, Damian Piotr
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Abstrakt: W artykule omówiono tematykę podłączania grzejników do instalacji, a konkretnie: armatury stosowanej w tym celu. I choć nie sposób w jednym, stosunkowo krótkim tekście wyczerpać tego tematu – z uwagi na mnogość możliwych rozwiązań – to pokusiliśmy się o pewną ich systematykę. Prezentujemy te rozwiązania, z którymi najczęściej można się spotkać w praktyce instalatorskiej, wyjaśniając, kiedy i dlaczego dane urządzenie czy zestaw urządzeń mogą być stosowane i wskazując optymalne sposoby podłączeń.]]>
<![CDATA[A revised approach to flood damage estimation in flood risk maps and flood risk management plans, Poland]]> Tue, 05 Oct 2021 11:43:46 +0200 Godyń, Izabela
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Abstrakt: This article describes the determination of asset values in residential and industrial areas in Poland that can be used in the preparation of flood hazard and risk maps (FRMs) and flood risk management plans (FRMPs). In the Floods Directive’s first cycle of implementation (2010–2015), German indicators of asset value were adapted to Polish conditions. This approach was used due to the lack of national statistics necessary to determine the value of property. In this study, the asset values in residential and industrial areas were prepared on the basis of the nationwide household wealth survey conducted in 2016 by the Narodowy Bank Polski (the central bank of Poland) and other data available from Statistics Poland. The proposed approach enables the determination of asset values based on real, validated data. The obtained indicators result in higher and more realistic values of the assets of households (buildings with contents) and the assets of companies (fixed assets and stocks) operating in both residential and industrial areas. The proposed approach, as an extension in relation to the first planning cycle, has been implemented in the second cycle of FRMP preparation in Poland.]]>
<![CDATA[Postęp w technologii wzmacniania gruntu z zastosowaniem kompozytów gruntobetonowych i fibrogruntobetonowych]]> Tue, 05 Oct 2021 08:48:08 +0200 Sołtysik, Robert; Brasse, Krystian; Tracz, Tomasz; Zdeb, Tomasz; Kańka, Stanisław
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Abstrakt: Przedstawiono nowoczesne, stosowane w praktyce inżynierskiej, metody wgłębnego mieszania gruntu rodzimego z zaczynem cementowym, w których wyniku powstaje gruntobeton bądź w przypadku dodatku włókien syntetycznych – fibrogruntobeton. Zaprezentowano wyniki badań doświadczalnych dotyczących wpływu ilości i długości włókien na zwiększenie wytrzymałości na rozciąganie przy zginaniu kompozytów fibrogruntobetonowych w porównaniu z niewzmocnionymi gruntobetonami.]]>
<![CDATA[Chemometric approach to characterization of the selected grape seed oils based on their fatty acids composition and FTIR spectroscopy]]> Mon, 04 Oct 2021 10:06:00 +0200 Mašán, Vladimir; Matwijczuk, Arkadiusz P.; Niemczynowicz, Agnieszka; Kycia, Radosław A.; Karcz, Dariusz; Gładyszewska, Bożena; Ślusarczyk, Lidia; Burg, Patrik
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Abstrakt: Addressing the issues arising from the production and trade of low-quality foods necessitates developing new quality control methods. Cooking oils, especially those produced from the grape seeds, are an example of food products that often suffer from questionable quality due to various adulterations and low-quality fruits used for their production. Among many methods allowing for fast and efficient food quality control, the combination of experimental and advanced mathematical approaches seems most reliable. In this work a method for grape seed oils compositional characterization based on the infrared (FTIR) spectroscopy and fatty acids profile is reported. Also, the relevant parameters of oils are characterized using a combination of standard techniques such as the Principal Component Analysis, k-Means, and Gaussian Mixture Model (GMM) fitting parameters. Two different approaches to perform unsupervised clustering using GMM were investigated. The first approach relies on the profile of fatty acids, while the second is FT-IR spectroscopy-based. The GMM fitting parameters in both approaches were compared. The results obtained from both approaches are consistent and complementary and provide the tools to address the characterization and clustering issues in grape seed oils.]]>
<![CDATA[Polskie Normy - (nie)obowiązkowość stosowania]]> Mon, 04 Oct 2021 08:50:27 +0200 Muniak, Damian Piotr
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Abstrakt: Z norm przedmiotowych w budownictwie i technice HVAC korzystamy na co dzień: przy projektowaniu, montażu lub podczas eksploatacji. Norm takich są tysiące. Jeśli weźmiemy jakikolwiek wyrób do ręki, to możemy być pewni, że dotyczy go co najmniej kilka norm: polskich, europejskich, międzynarodowych. Z powodu ich powszechności zwykle nie zastanawiamy się nad koniecznością ich stosowania. Skoro normy są i dotyczą niemal każdego aspektu technicznej aktywności człowieka oraz powołuje się je w instrukcjach i kartach technicznych wyrobów, to zapewne trzeba je stosować i kropka. Są więc w tym względzie źródłem prawa. Czy tak jest w istocie? – Odpowiedź jest jednoznaczna, ale zanim do niej dojdziemy, przyjrzyjmy się zagadnieniu od podstaw.]]>