Wyniki wyszukiwania - BazTech

1

Tribological Tests of Acrylic Teeth for Removable Dentures

Ryniewicz Wojciech, Bojko Łukasz, Pałka Paweł, Osada Piotr, Ryniewicz Anna

Tribologia

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2024

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nr 1

105--116

EN

The functionality of removable dentures is ensured by proper diagnostics and clinical modeling. No less important are the structural conditions and the biotribological and biomechanical context, which determine the wear resistance in the contact of opposing teeth and the contact of the denture plate with the stomatognathic system. The aim of the study is to evaluate acrylic teeth used in prosthetic reconstructions based on microstructural, micromechanical and tribological tests. Samples for testing were taken from teeth for removable dentures made by various manufacturers. Microstructural analyses were performed using an optical microscope and a scanning microscope. Microhardness and elasticity coefficient measurements were performed on the NHT device. Tribological tests were performed on a Roxana Machine Works tester using a friction node: ball – 3 discs made of the tested material. The conducted research allowed for the evaluation of the structural quality of acrylic teeth and the determination of the tribological interaction resulting from the contact of synthetic and natural teeth in the presence of artificial saliva.

PL

Funkcjonalność protez ruchomych zapewnia prawidłowa diagnostyka i modelowanie kliniczne. Nie mniej ważne są uwarunkowania strukturalne oraz kontekst biotribologiczny i biomechaniczny, które decydują o odporności na zużycie w kontakcie zębów przeciwstawnych oraz o kontakcie płyty protezy z układem stomatognatycznym. Celem opracowania jest ocena zębów akrylowych stosowanych w rekonstrukcjach protetycznych na podstawie badań mikrostrukturalnych, mikromechanicznych i tribologicznych. Próbki do badań pobierano z zębów do protez ruchomych wykonanych przez różnych producentów. Analizy mikrostrukturalne wykonano na mikroskopie optycznym i mikroskopie skaningowym. Pomiary mikrotwardości i współczynnika elastyczności przeprowadzono na urządzeniu NHT. Badania tribologiczne wykonano na maszynie Roksana Machine Works z zastosowaniem węzła tarcia: kula – 3 krążki z materiału badanego. Przeprowadzone badania pozwoliły na ocenę jakości strukturalnej zębów akrylowych oraz na wyznaczenie interakcji tribologicznej wynikającej z kontaktu zębów syntetycznych i naturalnych w obecności sztucznej śliny.

2

Badania zmian w strukturze płyt włóknisto-cementowych poddanych oddziaływaniom wybranych czynników eksploatacyjnych

Gorzelańczyk Tomasz

Przegląd Budowlany

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2024

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R. 95, nr 3

110--115

PL

W artykule przedstawiono wyniki badań wpływu zamrażania-rozmrażania oraz naświetlania promieniowaniem UV w komorze starzeniowej na strukturę płyt włóknisto-cementowych. W celu wykazania wpływu wyżej wymienionych czynników płyty w pierwszej kolejności przebadano z wykorzystaniem metody emisji akustycznej w próbie trójpunktowego zginania. Badania te wykazały wyraźny spadek liczby zarejestrowanych zdarzeń EA dla badanych płyt, szczególnie dla tych, które były poddane oddziaływaniu cykli zamrażania-rozmrażania w porównaniu z płytami referencyjnymi. Następnie w celu dokładniejszego zobrazowania zmian zachodzących w strukturze badanych płyt przeprowadzono badania z wykorzystaniem elektronowego mikroskopu skaningowego SEM.

EN

The article presents the results of research on the effect of cyclic freeze-thaw and UV irradiation on the structure of fibre-cement boards in an aging chamber. In order to demonstrate the impact of the above-mentioned factors, the panels were first tested using the acoustic emission method in the three-point bending test. These studies showed a clear decrease in the number of recorded EA events for the tested boards, especially for those that were subjected to freeze-thaw cycles compared to the reference boards. Then, in order to more accurately illustrate the changes occurring in the structure of the tested boards, tests were carried out using a scanning electron microscope (SEM).

3

Changes in properties and the internal structure of polyethylene polymer railway sleepers

Butor Anna, Labisz Krzysztof, Wierzbicki Łukasz

Diagnostyka

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2024

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Vol. 25, No. 2

art. no. 2024204

EN

Elements of the railway infrastructure are subject to difficult weather conditions, as well as changing dynamic loads resulting from the operation of a given part of the infrastructure. The following article presents an analysis of the internal macro and microstructure of a polymer railway sleeper made of reinforced polyethylene. The aim of the research was to obtain the results of structure, analysis of hardness measurements and identification of structure inconsistencies and the presence of other structural components in recycled polyethylene substrates. In terms of the tested material properties of the polyethylene sleepers, no significant changes in strength and plastic stability were found for the samples made of polyethylene tested before and after exposure to varying atmospheric conditions in the climatic chamber.

4

Synergistic toughening and strengthening of an epoxy resin modified by simultaneous use of two different modifiers

Białkowska Anita, Suroń Patryk, Kucharczyk Wojciech, Hanulikova Barbora, Bakar Mohamed

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 3

art. no. e149176

EN

The present work investigates the effect of modifying an epoxy resin using two different modifiers. The mechanical and thermal properties were evaluated as a function of modifier type and content. The structure and morphology were also analyzed and related to the measured properties. Polyurethane (PUR) was used as a liquid modifier, while Cloisite Na+ and Nanomer I.28E are solid nanoparticles. Impact strength (IS) of hybrid nanocomposites based on 3.5 wt% PUR and 2 wt% Cloisite or 3.5 wt% PUR and 1 wt% Nanomer was maximally increased by 55% and 30%, respectively, as compared to the virgin epoxy matrix, exceeding that of the two epoxy/nanoparticle binaries but not that of the epoxy/PUR binary. Furthermore, a maximum increase in IS of approximately 20% as compared to the pristine matrix was obtained with the hybrid epoxy nanocomposite containing 0.5 wt% Cloisite and 1 wt% Nanomer, including a synergistic effect, due most likely to specific interactions between the nanoparticles and the epoxy matrix. The addition of polyurethane and nanoclays increased the thermal stability of epoxy composites significantly. However, DSC results showed that the addition of flexible polyurethane chains decreased the glass transition temperatures, while the softening point and the service temperature range of epoxy nanocomposites containing nanofillers were increased. FTIR analysis confirmed the occurrence of interaction between the epoxy matrix and added modifiers. All SEM micrographs showed significant roughness of the fracture surfaces with the formation of elongated platelets, explaining the increase in mechanical properties of the epoxy matrix.

5

Analysis of mechanical properties and structure of samples filled with continuous glass fiber produced in composite filament fabrication technology

Marciniak Dawid, Sykutera Dariusz, Czyżewski Piotr

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 2

art. no. e148841

EN

The purpose of the study was to evaluate selected mechanical properties and structural characteristics of samples manufactured using composite filament fabrication (CFF) technology from Onyx material, whichwas filled with continuous glass fiber. Selected mechanical properties were correlated with the density of the resulting composite to determine the specific strength of the fabricated parts. The test specimens were manufactured on a Mark Two Enterprise machine (Markforged, USA) using composite filament fabrication (CFF) technology. The material used was polyamide 6.6 with a 20% short carbon fiber content with the trade name Onyx. Continuous glass fiber was used to reinforce the fabrication. The density of the manufactured samples was determined using a hydrostatic method. Methanol was used as the liquid. By determining the density of the samples, it was possible to estimate through appropriate calculations what specific strength and specific modulus the obtained composites would have. Determination of tensile and flexural strengths was carried out in accordance with ISO 527-1:2012 and ISO 178:2003. Determination of the impact tensile strength of the samples was carried out in accordance with ISO 8256, the beams were tested using the A method. Due to the high impact tensile strength, two 1 mm notches with an angle of 45°were made on the specimens. The image of the sample structure obtained by the CFF method was recorded using a CT scanner. A thermogravimetric test (TG) of the Onyx matrix material was carried out. The samples were tested approximately 72 hours after fabrication. Filling the samples with continuous glass fiber above 50% leads to a slight increase in impact resistance. The density of the composite increased by only 16% relative to the reference samples, resulting in a 389% increase in the maximum average flexural strength. Despite significant discontinuities in the structure of the produced composite, it was possible to record an increase in tensile strength and Young’s modulus by 606% and 370%, respectively.

6

Finansowanie długiem przedsiębiorstw konserwacji zabytków

Białek-Jaworska Anna

Wiadomości Konserwatorskie

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2023

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Nr 73

7--15

PL

Celem artykułu jest zidentyfikowanie determinant finansowania długiem i struktury kapitału firm z sektora konserwacji i ochrony zabytków w 23 krajach Europy. Wykorzystano estymator Arellano-Bond metody GMM do analizy dynamicznej danych panelowych dla próby 8086 obserwacji 1952 firm za lata 2011–2020. Wykorzystano dane ze sprawozdań finansowych z bazy TP Catalyst dostarczonej przez Bureau van Dijk. Wykazano, że małe firmy są bardziej zadłużone, łącznie długo- i krótkoterminowo, z tytułu kredytu bankowego i handlowego. Rentowne firmy mniej korzystają z kredytów bankowych i mają niższy wskaźnik długu do kapitału własnego, ale wyższe zobowiązania ogółem. Ryzyko niewykonania zobowiązań jest związane z wyższym zadłużeniem w banku, z tytułu kredytu handlowego i zadłużeniem ogółem, obejmującym zobowiązania bieżące i długoterminowe. Większy majątek trwały pozwala firmom na wydłużenie terminów zapadalności długu. Większe firmy o wyższej płynności zadłużają się na dłuższy okres. Kredyty bankowe wykorzystywane na ochronę zabytków mają krótszy termin zapadalności niż pozostałe zadłużenie.

EN

This paper aims to identify the determinants of debt financing and capital structure of companies in the conservation and preservation sector in twenty-three European countries. The Arellano-Bond estimator of the GMM method was used to analyze dynamic panel data for a sample of 8,086 observations of 1,952 firms for the years 2011–2020. Data from financial statements from the TP Catalyst database provided by Bureau van Dijk were used. It was shown that small firms are more indebted, combined long- and shortterm, to bank and trade credit. Profitable companies used bank loans less and had a lower debt-to-equity ratio but higher total liabilities. Default risk was associated with higher bank debt, trade credit and total debt, including current and long-term liabilities. Higher fixed assets allowed companies to extend debt maturities. Larger companies with higher liquidity were indebted for more extended periods. Bank loans used for conservation had shorter maturities than other debt.

7

Właściwości cieplne materiałów o strukturze TPMS wykonanych w technologii druku addytywnego SLS

Anwajler Beata, Szkudlarek Mikołaj

Rynek Energii

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2023

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Nr 1

11--20

PL

Zwiększenie efektywności energetycznej izolacji cieplnych jest jednym z priorytetowych zagadnień dotyczący hamowania negatywnych procesów degradacji środowiska, które towarzyszą intensywnemu rozwojowi rasy ludzkiej. Wśród perspektywicznych kierunków pozwalających uzyskać potrzebne modernizacje uwzględnia się bionikę. Struktury występujące w naturze cechują się niekiedy wysokim stopniem złożoności. Dlatego możliwość uzyskiwania takich obiektów może być problematyczna przy wykorzystywaniu tradycyjnych technik wytwarzania. W takiej sytuacji uzasadnione jest zastosowanie technologii addytywnych, które pozwalają kształtować elementy bez ograniczeń. W artykule przedstawiono projekt konstrukcji materiałów przestrzennych z rdzeniem TPMS, których kształt odzwierciedla strukturę bioniczną wnętrza kości. W przypadku jedno- i wielowarstwowych struktur drukowanych metodą SLS obliczeniowa wartość współczynnika przewodzenia ciepła została określona na podstawie pomiarów i obliczeń. Przeprowadzono analizę statystyczną w celu określenia wpływu kierunku przepływu ciepła oraz struktury wewnętrznej i uwarstwienia materiałów prototypowych na wartości współczynnika przewodzenia ciepła i współczynnika oporu cieplnego. Na podstawie analizy wielokryterialnej ANOVA określono optymalny skład kompozytu zgodnie z przyjętymi kryteriami optymalizacji. Najniższa możliwa przewodność cieplna izolacji wyniosła 0,034 W/(m × K). Najwyższy możliwy opór cieplny wyniósł 0,586 m2K/W. Izolacja termiczna wykonana z prototypowych przegród izolacyjnych o konstrukcji TPMS charakteryzuje się dobrymi parametrami izolacyjnymi.

EN

Increasing the energy efﬁciency of thermal insulation is one of the priority issues related to the inhibtion of negative environmental degradation processes accompanying the intensive development of the human rac Bionics is considered among the prospective directions for obtaining the necessary modemizations. Structures o curring in nature are sometimes characterized by a high degree of complexity. Therefore, the possibility of obtain ing such objects can be problematic when using traditional manufacturing techniques. In such a situation, it 1 justiﬁed to use additive technologies that allow to shape elements without restrictions. The article presents a desig of spatial materials with a TPMS core, the shape of which reﬂects the bionic structure of the bone interior. In th case of single and multi-layer structures printed with the SLS method, the calculated value of the thermal conduc tivity coefﬁcient was determined on the basis of measurements and calculations. A statistical analysis was carrie out in order to determine the inﬂuence of the heat ﬂow direction and the internal structure and lamination of th prototype materials on the values of the thermal conductivity coefﬁcient and the coefﬁcient of thermal resistanc Based on the multi-criteria ANOVA analysis, the optimal composition of the composite was determined in accort ance with the adopted optimization criteria. The lowest possible thermal conductivity of the insulation was 0.03 W/(mXK). The highest possible thermal resistance was 0.586 mzK/W. Thermal insulation made of prototype TPM insulation partitions is characterized by good insulation parameters.

8

Glass microspheres thermo-deformation sintering processes in the technologies of obtaining materials for underwater technical equipment

Kazymyrenko Yuliia, Solomoniuk Natalya, Drozd Oxana

Polish Maritime Research

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2023

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nr 3

174--180

EN

In this work, the important scientific and technical problem of creating multifunctional composite materials for shipbuilding and ocean engineering was solved. The work aimed to study the thermal deformation processes of sintering glass microspheres to obtain lightweight glass composites with a cellular structure that provides positive buoyancy and sound insulation properties. For this purpose, glass microspheres of Na2O‒SiO2 and Na2O‒B2O3‒SiO2 composition with a dispersion of 10 to 60 μm were used as raw materials. They were sintered to form a closed, porous structure. The theoretical substantiation of technological parameters is based on the concepts of solid state and glassy state chemistry and physicochemical concepts of glass softening processes. The process of hot-pressing glass microspheres without plasticisers and additives was investigated. The author’s own laboratory equipment was used for the experiments. The sintering intensity was determined from the results of shrinkage processes; the kinetic shrinkage curves were constructed in semilogarithmic coordinates. The glass composite samples were examined by optical and electron microscopy. As a criterion, the storage of spherical microspheres under the influence of simultaneous heating to 700 °C with the application of pressure in the range of 0,5 to 1,5 MPa was chosen. It was established that the formation of a predominantly closed-porous structure of glass composites with a density of 350...600 kg/m3 occurs by the mechanisms of viscous glass phase flow through liquefaction processes in the walls of microspheres. At the same time, shrinkage processes in the linear direction reach up to 50%. The acoustic properties were investigated by measuring the differences in sound pressure levels in octave frequency bands using a Kundt pipe. The water absorption of the glass composite samples was determined at hydrostatic pressures up to 20 MPa. The research results were compared with the characteristics of analogue composites, such as syntactic foams and foam glass. The developed materials can be used in the design and manufacture of technical equipment for research and maintenance of underwater infrastructure. The prospects for further research are related to the feasibility study and marketing research on implementing the developed glass composites.

9

Failure analysis during the operation of offshore oil and gas structures

Ben Nengjun, Vytyaz Oleg, Jin Xin, Hrabovskyi Roman, Kopei Bogdan

Nafta-Gaz

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2023

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R. 79, nr 8

529--536

EN

: Failures caused by offshore oil and gas structures operations are investigated. This work is based on the description and analysis of real case studies of accidents on offshore stationary and floating platforms; it combines foundational knowledge and current research on the latest developments in the field. It was shown that strength characteristics of offshore reinforced concrete and steel elements change during operation and cause the accumulation of defects and damages. It was established that corrosive wear, corrosion-mechanical processes, and crack-like defects are the decisive causes of element failure. It was shown that up to 60–75% of all damages to and failures of offshore engineering facilities' steel structures occur due to the corrosion-mechanical influence of an aggressive environment and force loads. This means that issues of corrosion-mechanical failure of such structures have become an industrial-scale problem. It thus allows us to draw the following conclusions: improvement of steel offshore drilling platforms (ODPs) maintenance system involves the development of new models and methods of managing the operational reliability of these structures, aimed at making decisions that take into account the crack resistance and fatigue-corrosion strength of steel ODPs in contact with the corrosive-active environment. Only on the basis of such scientifically and economically grounded models can rational strategies be shaped for carrying out revisions of the ODPs technical condition, ensuring the necessary level of their reliability during the operation period. This investigation can be very helpful to improve the design and construction of more reliable and durable offshore stationary and floating platforms.

PL

W artykule omówiono uszkodzenia powstające w trakcie eksploatacji podmorskich złóż ropy i gazu. Niniejsza praca opiera się na opisie i analizie rzeczywistych przypadków wypadków na morskich platformach stacjonarnych i pływających, łączy ona podstawową wiedzę z bieżącymi badaniami nad najnowszymi osiągnięciami w tej dziedzinie. Wykazano, że charakterystyki wytrzymałościowe elementów betonowych i stalowych konstrukcji morskich w trakcie eksploatacji zmieniają się i kumulują wady i uszkodzenia. Ustalono, że decydującymi przyczynami uszkodzeń elementów są zużycie korozyjne, procesy korozyjno-mechaniczne oraz defekty spękaniowe. Wykazano, że do 60–75% wszystkich uszkodzeń i wypadków stalowych urządzeń morskich powstaje w wyniku korozyjnego i mechanicznego działania agresywnego środowiska oraz obciążeń siłowych. Oznacza to, że kwestie korozyjnego mechanicznego uszkodzenia takich konstrukcji stały się problemem na skalę przemysłową. Na tej podstawie można wyciągnąć następujące wnioski: doskonalenie systemu utrzymania morskich stalowych platform wiertniczych wiąże się z opracowywaniem nowych modeli i metod zarządzania niezawodnością eksploatacyjną tych konstrukcji, ukierunkowanych na podejmowanie decyzji uwzględniających odporność na pękanie oraz odporność na korozję zmęczeniową stalowych platform wiertniczych stykających się ze środowiskiem korozyjno-aktywnym. Tylko w oparciu o tego typu, naukowo i ekonomicznie ugruntowane modele, można kształtować racjonalne strategie przeprowadzania przeglądów stanu technicznego morskich platform wiertniczych, zapewniające niezbędny poziom ich niezawodności w okresie eksploatacji. Badania te mogą być bardzo pomocne w ulepszaniu projektowania i budowy bardziej niezawodnych i trwałych morskich platform, zarówno stacjonarnych, jak i pływających.

10

Przy pewnym wysiłku można uzyskać ciekawą formę obiektu i optymalną konstrukcję

Mosty

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2023

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nr 4

18-20

PL

Dr inż. Mariusz Pustelnik, Prezes Zarządu Pracowni Projektowej MOSTOPOL sp. z o.o., w rozmowie z redakcją czasopisma „Mosty” odpowie na pytania dot. Nowoczesnych technik projektowania mostów i najważniejszych aspektów, na które należy zwrócić uwagę podczas ich projektowania.

11

Zmiany w konstrukcji oraz elementach składowych stolarki okienno-drzwiowej wpływające na jej właściwości techniczno-użytkowe

Kopyłow Ołeksij

Materiały Budowlane

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2023

|

nr 8

59--61

12

Wiadukty Trasy Łazienkowskiej nad ulicą Paryską w Warszawie po pięćdziesięciu latach użytkowania

Zobel Henryk, Wróbel Marcin

Inżynieria i Budownictwo

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2023

|

R. 79, nr 7-8

354--359

PL

Wiadukty w ciągu Trasy Łazienkowskiej nad ulicą Paryską w Warszawie funkcjonują prawie pięćdziesiąt lat. Obecnie trwają przygotowania do ich rozbiórki. W artykule przestawiono niektóre powody, które mogły przyczynić się do podjęcia przez zarządcę decyzji o wymianie konstrukcji.

EN

Viaducts along Trasa Łazienkowska (municipal expressway) in Warsaw are used almost 50 years. Their technical behavior is critical. The paper presents causes of making decision to demolish them and build new one.

13

Analysis on Chinese Ming Pibian Forms, Techniques and Social Functions

Hao Jixu, Niu Li

Fibres & Textiles in Eastern Europe

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2023

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Vol. 31, no. 4

66--74

EN

The pibian (皮弁, pronounced as pì biàn in Chinese) is a kind of cap specific to China. Before the Ming dynasty (1368-1644), it was made of deer hide, while in the Ming dynasty, it was woven with bamboo filament. Through analysis on the forms, techniques and materials used in the pibian preserved, we discovered that pibian displayed a superb artisanship level. The sign of status was depicted through the pibian’s structures and ornaments in an ingenious way, and its structures and components were closely linked with the social culture.

14

Influence of filler introduction method on structure and properties of polymer composites based on polyurethane and silver nanoparticles

Lysenkov Eduard A., Striutskyi Oleksandr V.

Composites Theory and Practice

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2023

|

R. 23, nr 3

145--152

EN

Polymer nanocomposites based on segmented polyurethane and silver nanoparticles (AgNPs) were synthesized using different methods of nanoparticle introduction. The dependence of their structure, thermophysical and antimicrobial properties on the method of introducing AgNPs was studied. It was established that the method of introduction affects both the spatial distribution of the filler particles and the final properties of the material. The introduction of AgNPs by the ultrasonic dispersion method leads to inhibition of the growth of the crystalline phase, which is associated with the formation of aggregates from AgNPs of small size, which have a large polymer-filler interaction surface. It is shown that the introducing AgNPs from a colloidal solution leads to an increase in the degree of crystallinity of the polymer matrix, which is a consequence of the nucleation effect of nanosized silver particles on the formation of the crystalline phase. It was established that the method of introducing nanoparticles does not affect their final antimicrobial properties. Owing to their unique characteristics, synthesized nanocomposite films can be promising for use as antimicrobial coatings.

15

Thermoplastic hardened Cu-Ni-Si-Ag alloy

Krupińska Beata, Chulist Robert, Kondracki Marcin, Labisz Krzysztof

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 2

art. no. e145683

EN

The paper aims to investigate the influence of silver addition on the microstructure of CuNi2Si1 alloys. The investigated copper alloy was cast and then supersaturated, plastically deformed on the Gleeble 3800 simulator and finally aged. Structural changes were examined using optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Orientation mapping was completed with FEI Quanta 3D field emission gun scanning electron microscope (SEM) equipped with TSL electron backscattered diffraction (EBSD) system. The effect of structural and microstructural changes on hardness and conductivity was also investigated. Based on the mechanical tests it was found that the mechanical properties and conductivity are improved due to heat and plastic treatment. It was also found that the precipitation hardening raises the hardness to the level of 40% whilst an increase in conductivity by 20% is observed.

16

Development of the Construction of City Buses in Terms of Reducing the Curb Weight of the Vehicle

Caban Jacek, Seńko Jarosław, Nowak Radosław, Rumianek Przemysław, Podkowski Krzysztof, Wolska Natalia

Archiwum Motoryzacji

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2023

|

Vol. 102, nr 4

91--104

EN

Modern city buses are made of various construction materials and the share of material groups has changed over the decades. By replacing heavy materials for structural elements or bus components with their lighter counterparts, the kerb weight of the bus can be reduced by up to several hundred kilograms. This article presents the issues of the development of city bus design in terms of passenger space comfort and bus structure in the context of reducing the vehicle's own weight since the 1970s. The main changes in vehicle design allowing for reducing the weight of structural elements of bodies and chassis as well as the main assemblies in city buses are presented as well as research on body types in terms of aerodynamics, safety and travel comfort. It has been shown that reducing the weight of the bus does not negatively affect its load capacity and the new bus designs are equipped with safety and comfort systems, including ABS (Anti-lock Braking System), ASR (Automatic Stability Regulation), ESP (Electronic Stability Program) and air conditioning in the passenger space. Thanks to modern light construction materials, we gain the opportunity to improve safety and comfort without losing the transport capabilities developed as a result of the development of city buses over the years.

17

Synthesis of Ti-Nb-Zr Alloys Combined Powder Metallurgy and Arc Melting Methods

Matuła Izabela, Dercz Grzegorz, Prusik Krystian, Szklarska Magdalena, Kazek-Kęsik Alicja, Simka Wojciech, Sudoł E.

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 3

1115--1120

EN

Scientists and medics are still searching for new metallic materials that can be used in medicine, e.g., as material for implants. The following article proposes materials based on titanium with vital elements prepared by combined powder metallurgy and arc melting methods. Four compositions of Ti-28Ta-9Nb, Ti-28Ta-19Nb, Ti-28Ta-9Zr and Ti-28Ta-19Zr (wt.%) have been prepared. The tested material was thoroughly analyzed by X-ray diffraction and scanning electron microscopy. Qualitative phase analysis using X-ray diffraction showed the presence of two phases, α' and β titanium. In addition, a microhardness test was conducted, and the material was characterized in terms of corrosion properties. It was found that the corrosion resistance decreases with an increase of the β phase presence.

18

Effect of Nb and Zr alloying additives on structure and properties of Ti-Ta-Nb-Zr alloys for medical applications

Dercz Grzegorz, Matuła Izabela, Prusik Krystian, Zając J., Szklarska Magdalena, Kazek-Kęsik Alicja, Simka Wojciech

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 3

1137--1142

EN

This work investigated two titanium-based alloys with a constant tantalum content and variable contents of alloy additives - niobium and zirconium. The Ti-30Ta-10Zr-20Nb (wt.%) and Ti-30Ta-20Zr-10Nb (wt.%) alloys were obtained using a combination of powder metallurgy and arc melting methods. The influence of alloying additives on the structure and properties of the Ti-Ta-Nb-Zr system was studied using, among others: X-ray diffraction and scanning electron microscopy. The X-ray diffraction confirmed the single-β-phase structure of both alloys. In addition, the microscopic analysis revealed that a higher amount of zirconium favoured the formation of larger grains. However, the microhardness analysis indicated that the alloy with the higher niobium content had the higher microhardness. Importantly, the in vitro corrosion study revealed that the addition of niobium promoted the better corrosion resistance of the investigated alloy.

19

Prediction of coalbed methane content based on seismic identification of key geological parameters: a case in a study area, Southern Qinshui Basin

Liu Jing, Chang Suoliang, Zhang Sheng, Li Yanrong, Hao Yaju, He Guoxian, He You, Liu Bo

Acta Geophysica

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2023

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Vol. 71, no. 6

2645--2662

EN

The coalbed methane content (CMC) is an important parameter to evaluate the degree of coalbed methane enrichment, and also an important reservoir parameter to calculate coalbed methane resources, productivity prediction and reservoir simulation. Accurately identifying the distribution of CMC is crucial to the exploration of CBM. In this study, we developed a prediction method for the CMC distribution via seismic techniques identification of key geological parameters such as structure, coal thickness and sedimentation. Firstly, the geological factors that control the generation and preservation of CBM in the study area are quantitatively characterized by using five parameters: surface (X1), residual (X2), dip (X3), coal thickness (X4) and the ratio of sand to mud (X5). Secondly, the geological parameters are extracted by seismic structure interpretation and inversion prediction technology. Thirdly, the key geological parameters of CMC are screened out by grey correlation analysis. Finally, the functional relationship of CMC and the key geological parameters is established to predict the CMC distribution. The method is applied to the CMC distribution prediction of two coal seams of a study area in the southern Qinshui Basin, China. Results show that different coal seams differ in key geological parameters of CMC, resulting in various CMC distribution laws. The CMC prediction method based on the key geological factors can effectively delineate the CBM enrichment area in the study area, providing important reference for the CBM exploration and development.

20

Dobrze skrojony zielony dach

Lech Aleksander

Zieleń Miejska

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2022

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Nr 11

70--71

PL

Wiele jest czynników wymagających uwzględnienia w procesie projektowania układu warstw zapewniających właściwe warunki do uprawy roślin na utwardzonych powierzchniach architektonicznych. Jakie uwarunkowania dotyczą tego rodzaju struktur?