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Chicken feather keratin as a source of bioactive peptides useful in prevention of metabolic disorders – in silico and in vitro hydrolysis
PublicationProtein derived bioactive peptides not only serve as nutrients but can also exert drug-like activity, e.g. antidiabetic, antihypertensive, or antimicrobial, to name a few. Most biopeptides have beneficial effects on health that make them attractive for nutraceutical applications. The majority of bioactive peptides have been obtained from food proteins, but protein-rich by-products generated by agriculture...
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Topography measurement methods evaluation for entire bending-fatigued fracture surfaces of specimens obtained by explosive welding
PublicationIn this paper, the methods of compensation of differences in the results of entire bending-fatigued fracture surface topographies were presented. The roughness evaluation was performed with a focus variation microscope and confocal surface topography measurement techniques. The differences in the ISO 25178 roughness parameters were investigated and procedures for their compensation were studied. It was found that various types...
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Orientation effects on the fracture behaviour of additively manufactured stainless steel 316L subjected to high cyclic fatigue
PublicationIn this paper, stainless steel 316L (SS316L) bars were additively manufactured (AM) in three orientations (Z – vertical, XY – horizontal, ZX45 – midway between vertical and horizontal) by using the Laser Powder Bed Fusion Melting (LPBF-M) method. The AM specimens were subjected to load control fatigue testing under full tension and compression (R = -1) at stress amplitudes ±350, ±400 and ±450 MPa. The XY and ZX45 printing orientations...
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The fracture behaviour of notched PMMA specimens under simple loading conditions – Tension and torsion experimental tests
PublicationThis paper presents the results of experimental testing of flat PMMA specimens during uniaxial loading conditions. Two separate tests were conducted: tensile and torsion. The specimens were weakened with V-type edge notches with different root radii: 0.5; 2 and 10 mm. The specimens were made in two thickness variants: 5 and 15 mm. Monotonic tensile and torsion tests were carried out while keeping the averaged strain rate constant,...
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Detremination of the cutting power of the sawing process using both preliminary sawing data and modern fracture mechanics
PublicationPrzedstawiono medodykę prognozowania mocy skrawania dla procesu piłowania drewna cienkimi piłami. Przewidywanie zapotrzebowania mocy skrawania oparte jest na współczesnej mechanice pękania, a do wyznaczenia stałych materiałowych: wiązkości materiału oraz niszczących napężeń ścinających wykorzystano wyniki wstępnych badań eksperymentalnych. Błędy prognozowania nie przekraczają 15.5% dla przypadku cienkich pił gdy rolę znacząca odgrywają...
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Brittle fracture of 100-, 110-, 111-oriented Cu crystals: MD vs. TB/MD approach
PublicationPrzeprowadzono wieloskalowe symulacje nanoindentacji miedzi nieskończenie twardym narzędziem, przy zastosowaniu metody dynamiki molekularnej, z siłami liczonymi na bieżąco w formalizmie ciasnego wiązania (TB). Przedstawiono wyniki dla trzech orientacji krystalicznych podłoża. Badano efekt dołączenia obliczeń TB na siłę normalną odczuwaną przez narzędzie i na przemieszczenia atomów podłoża, przez porównywanie z symulacją czystą...
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Formation and Growth of the Crack in Bonded Joints Under Mode I Fracture: Substrate Deflection at Crack Vicinity
PublicationAdhesive bonding is now commonly used in aircraft, cars, boats, etc. In these applications, thin panels are often bonded. In such thin structures, heterogeneous mechanical loading along the bondline edge (or potential crack front), is likely to arise due to 3D structural effects. The crack front and its vicinity is a special region, in that it is where structural properties of the adherend material meet those of the adhesive (discontinuity)....
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Chicken feather-derived carbon electrodes for capacitive deionization using poly(vinyl alcohol)-glutaraldehyde as the binder
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Selection of Methods of Surface Texture Characterisation for Reduction of the Frequency-Based Errors in the Measurement and Data Analysis Processes
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Prediction of fracture toughness in fibre-reinforced concrete, mortar, and rocks using various Machine learning techniques
PublicationMachine Learning (ML) method is widely used in engineering applications such as fracture mechanics. In this study, twenty different ML algorithms were employed and compared for the prediction of the fracture toughness and fracture load in modes I, II, and mixed-mode (I-II) of various materials, including fibre-reinforced concrete, cement mortar, sandstone, white travertine, marble, and granite. A set of 401 specimens of “Brazilian...
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Correlation between Fractal Dimension and Areal Surface Parameters for Fracture Analysis after Bending-Torsion Fatigue
PublicationThis paper investigates the fracture surface topography of two steel and aluminum alloys subject to bending-torsion fatigue loadings, as well as their susceptibility to fatigue performance and failure mechanisms. Using fracture surface topography data analysis, elements with different geometries were elaborated. A correlation between the fractal dimension, other selected parameters of surface topography such as areal Sx, and...
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The use of a two-phase Monte Carlo material model to reflect the dispersion of asphalt concrete fracture parameters
PublicationThe work covers comprehensive laboratory tests of semi-circular bending (SCB) of asphalt concrete samples. The results of two test series, including four and 32 SCB specimens, indicate a substantial scatter of force–deflection (F-d) histories. The numerical analysis is aimed to reflect the maximum breaking load and fracture energy of the samples, pointing out their random character. The original simulation-based fictitious Monte...
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Fatigue fracture surface metrology of thin-walled tubular austenitic steel specimens after asynchronous loadings
PublicationThis paper aims to study the effect of asynchronous axial-torsional strain-controlled loading histories on fracture surface behavior of thin-walled tubular X5CrNi18-10 (304/304L) austenitic steel specimens. Tests under pure axial loading and pure torsional loading are also conducted to better segregate the effect of multiaxiality. The fractures surface topographies were examined through the profiles over the entire surface with...
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Characterization of fracture process in polyolefin fibre-reinforced concrete using ultrasonic waves and digital image correlation
PublicationThis study explores the monitoring of the fracture process in concrete beams and aims to characterize the evolution of damage in polyolefin fibre-reinforced concrete beams by utilizing the integrated application of two measurement techniques, digital image correlation and ultrasonic testing. The interpretation of registered wave time histories data was provided by the calculation of the magnitude-phase-composite metrics. An efficient...
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Calculations of fracture process zones on meso-scale in notched concrete beams subjected to three-point bending.
PublicationW artykule przedstawiono wyniki numeryczne MES modelowanie belek betonowych z nacięciem na poziomie skali mezo. Beton został opisany na poziomie skali mezo jako stochastyczny materiał 3-składnikowy złożony z kruszywa, zaczynu cementowego oraz stref kontaktu. Obliczenia wykonano przy wykorzystaniu modelu degradacji sztywności z nielokalnym osłabieniem. Zbadano wpływ stochastycznego rozkładu kruszywa, średnicy, kształtu oraz zagęszczenia...
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Investigations on fracture in reinforced concrete beams in 3-point bending using continuous micro-CT scanning
PublicationThis study explores a fracture process in rectangular reinforced concrete (RC) beams subjected to quasi-static three-point bending. RC beams were short and long with included longitudinal reinforcement in the form of a steel or basalt bar. The ratio of the shear span to the effective depth was 1.5 and 0.75. The focus was on the load–deflection diagram and crack formation. Three-dimensional (3D) analyses of the size and distribution...
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Microscopic examination of the texture of paper products
Open Research DataAtomic force microscopy (AFM) can be used to study the state of the paper fibers with the aim of providing qualitative and semi-quantitative information on degradation and aging. The work [1] reports the results of tests of various paper products subjected to deliberate aging processes under the influence of various factors. Chemical and biological...
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Third-order nonlinear optical features of zirconia-added lead silicate glass ceramics embedded with Pb2Fe2O5 perovskite crystal phases and role of Fe ions
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Ocena wpływu inwestycji na zdrowie w świetle badań nad terapeutycznymi właściwościami krajobrazu. Health Impact Assessment and the investigations of landscape therapeutic features.
PublicationPraca przedstawia tematykę oceny wpływu inwestycji na zdrowie w świetle badań nad terapeutycznym wpływem krajobrazu na zdrowie człowieka. Ocenę wpływu inwestycji na zdrowie – uzupełniającą stosowaną w Unii Europejskiej procedurę ocen oddziaływania na środowisko (OOŚ) – zaprezentowano jako narzędzie umożliwiające ochronę zdrowia człowieka w przypadku realizacji szkodliwych dla niego inwestycji. Wiele działań, jak oddzielenie budynków...
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The Influence of Weather Anomalies on Mercury Cycling in the Marine Coastal Zone of the Southern Baltic—Future Perspective
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A contribution to the moss and liverwort flora of the Reberce Nature Reserve at the Przemyśl Foothills (Western Carpathians, Poland)
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Inspired by Nature: The Use of Plant-derived Substrate/Enzyme Combinations to Generate Antimicrobial Activity in situ
PublicationThe last decade has witnessed a renewed interest in antimicrobial agents. Plants have received particular attention and frequently rely on the spontaneous enzymatic conversion of an inactive precursor to an active agent. Such two-component substrate/enzyme defence systems can be reconstituted ex vivo. Here, the alliin/alliinase system from garlic seems to be rather effective against Saccharomyces cerevisiae, whilst the glucosinolate/myrosinase...
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Iranian future healthcare professionals' knowledge and opinions about rare diseases: cross-sectional study
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Improvement of machinability of Ti and its alloys using cooling-lubrication techniques: a review and future prospect
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To donate or not to donate? Future healthcare professionals’ opinions on biobanking of human biological material for research purposes
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Iranian future healthcare professionals’ knowledge and opinions about rare diseases: cross‑sectional study
PublicationBackground: Rare diseases are a new global health priority, requiring evidence-based estimates of the global prevalenceof diseases to inform public policymakers and provide a serious challenge to the healthcare system that must not be ignored. The purpose of this study is to investigate Iranian future healthcare professionals’ knowledge and opinions about rare diseases.Results: A total of 6838 students responded...
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The mediational role of future and past time perspectives in the relationship between negative affectivity and sense of coherence
PublicationSense of coherence (SoC) can promote positive coping, and one of its most prominent negative correlates is negative affectivity (NA). In the current study, we hypothesized that future and past time perspectives (TPs) will mediate the relationship between sense of coherence and negative affectivity, and the inverse relationship. The study was questionnaire-based, performed online. N = 719 participants aged 25-45 from...
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To donate or not to donate? Future healthcare professionals’ opinions on biobanking of human biological material for research purposes
PublicationBackground Over the last few decades biobanks have been recognised as institutions that may revolutionisebiomedical research and the development of personalised medicine. Poland, however, still lacks clear regulationsregarding the running of biobanks and the conducting of biomedical research. While the awareness of the generalpublic regarding biobanks is low, healthcare professions and medical students also...
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Potential of silicon carbide MOSFETs in the DC/DC converters for future HVDC offshore wind farms
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Bacterial cellulose in the field of wound healing and regenerative medicine of skin: recent trends and future prospectives
PublicationIn this overview, we focused on the bacterial cellulose (BC) applications, described in recently published scientific papers, in the field of skin regenerative medicine and wound care industry. Bacterial cellulose was proven to be biocompatible with living tissues. Moreover, its mechanical properties and porous structure are considered to be suitable for biomedical applications. It is due to the fact that porous structure of bacterial...
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Bibliometric analysis of artificial intelligence in wastewater treatment: Current status, research progress, and future prospects
PublicationWastewater treatment is an important topic for improving water quality and environmental protection, and artificial intelligence has become a powerful tool for wastewater treatment. This work provides research progress and a literature review of artificial intelligence applied to wastewater treatment based on the visualization of bibliometric tools. A total of 3460 publications from 2000 to 2023 were obtained from the Web of Science...
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The nature of emitting states in electroluminescence of polymeric films do-ped with anthracene andanthracene-based supramolecules
PublicationZaobserwowano nową odmianę bi-molekularnych stanów wzbudzenia elektronowego w polimerowych jednowarstwowych diodach EL z molekułami antracenu wbudowanymi bezpośrednio w matrycę poliwęglanową, jak i pośrednio przez ich włączenie jako grup chromoforowych w dużych makromolekułach rotaxanowych. Stwierdzono, że obok typowej emisji ekscymerowej pojawia się długofalowe pasmo elektromerowe. Pasmo to związane jest z emisją kolumbowsko związanych...
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Hydrochar-nanoparticle integration for arsenic removal from wastewater: Challenges, possible solutions, and future horizon
PublicationArsenic (As) contamination poses a significant threat to human health, ecosystems, and agriculture, with levels ranging from 12 to 75% attributed to mine waste and stream sediments. This naturally element is abundant in Earth's crust and gets released into the environment through mining and rock processing, causing ≈363 million people to depend on As-contaminated groundwater. To combat this issue, introducing a sustainable hydrochar...
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Recent developments and future trends in solid phase microextraction techniques towards green analytical chemistry
PublicationSolid phase microextraction find increasing applications in the sample preparation step before chromatographic determination of analytes in samples with a complex composition. These techniques allow for integrating several operations, such as sample collection, extraction, analyte enrichment above the detection limit of a given measuring instrument and the isolation of analytes from sample matrix. In this work the information about...
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A framework of open government data (OGD) e-service quality dimensions with future research agenda
PublicationPurpose This research paper aims to present a framework of open government data (OGD) relating to e-service quality dimensions. In addition, it provides a research agenda for the e-service delivery of OGD. Design/methodology/approach A literature review pertaining to e-service quality with special reference to e-government was delivered to deduce the key dimensions of e-service quality for OGD. Findings Five e-service quality dimensions...
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The Specific Nature of Chemical Composition of Water from Volcanic Lakes Based on Bali Case Study
PublicationThe research area was localized in the Indonesian Archipelago, at the latitude of eight and nine degrees S on the one of the Lesser Sunda group island provinces, Bali (563,3 km2). Two massive calderas (Mount Batur 1717 m above sea level.; Mount Sangiyang 2093 m above sea level) are one of the most prominent landforms in the chain of volcanic mountain ranges of the Bali Island. Lake Batur (17,18 km2) and Batur Spring (which are...
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Open Innovation Competence for a Future-Proof Workforce: A Comparative Study from Four European Universities
PublicationDigital transformation is a key driving force of open innovation to capture and transfer knowledge inside and outside of a company’s bounds. New challenges in organizing multiple knowledge flows imply the need for increased competences related to this paradigm of future employees. In this article, we organize and aggregate the competencies required for open innovation collaboration and develop a competence profile that organizes...
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Piotr Jaskuła dr hab. inż.
PeopleI am a Faculty member (Associate Professor, Highway and Transportation Research Department) at the Faculty of Civil and Environmental Engineering, Gdansk University of Technology, Poland).My main research interests include: pavement structures, interlayer bonding, pavement materials, recycling of road pavements, asphalt mixtures, bitumens, construction and maintenance of pavement structures.My lectures at the University include:...
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Acid-aided epoxy-amine curing reaction as reflected in epoxy/Fe3O4 nanocomposites: Chemistry, mechanism, and fracture behavior
PublicationThis work seeks to answer the question whether or not the presence of acid functional groups accelerate epoxyamine curing reaction. Epoxy/Fe3O4 nanocomposite was considered as a case, where discussions are based on chemistry, mechanism behind curing reactions and fracture behavior influenced by acid assistance to crosslinking. Fe3O4 magnetic nanoparticles (MNPs) with nanosilica decorative layer (B-MNP) were synthesized and subsequently...
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Using the social return on investment (SROI) as a measure of the effectiveness of social innovation projects implemented under public policies
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Zinc Oxide Nanoparticles Cytotoxicity and Release from Newly Formed PMMA–ZnO Nanocomposites Designed for Denture Bases
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Characterization of Corrosion-Induced Fracture in Reinforced Concrete Beams Using Electrical Potential, Ultrasound and Low-Frequency Vibration
PublicationThe paper deals with the non-destructive experimental testing of the reinforced concrete beams under progressive corrosion. A series of experiments using electrical potential, ultrasound and low-frequency vibrations techniques are reported. Electrical potential and natural frequencies were used to characterise and monitor the corrosion process at its initial state. The P-wave velocity measurements were proved to be effective in...
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The experimental and numerical investigation of fracture behaviour in PMMA notched specimens under biaxial loading conditions – Tension with torsion
PublicationThis paper presents the results of experimental fracture test of flat PMMA specimens under biaxial loading condition tension with torsion (proportional). The specimens were made in two thicknesses: 5 and 15 mm and were weakened with V-type edge notches with different root radii: 0.5; 2 and 10 mm. Thanks to the ARAMIS 3D 4 M non-contact vision system, measurement of the elongation and twist angle were recorded. During experimental...
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The Effect of Freezing Sheep’s Milk on the Meltability, Texture, Melting and Fat Crystallization Profiles of Fresh Pasta Filata Cheese
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LF NMR spectroscopy analysis of water dynamics and texture of Gluten-Free bread with cricket powder during storage
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SHEAR YIELD STRESSES AND FRACTURE TOUGHNESS OF SCOTS PINE (PINUS SYLVESTRIS L.) ACCORDING TO THE RAW MATERIAL PROVENANCE
PublicationIn this paper values of the fracture toughness and of shear yield stress in the shear zone of Scots pine are presented. Tests of cutting were carried on samples of Scotch pine (Pinus sylvestris L.) wood of five provenances from Poland. These experimentally cutting tests were carried on the sash gang saw PRW-15M and the values of cutting power were obtained. The values of fracture toughness and shear yield stress based on Atkins’s...
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Fracture Surface Behavior of 34CrNiMo6 High-Strength Steel Bars with Blind Holes under Bending-Torsion Fatigue
PublicationThe present study evaluates the fracture surface response of fatigued 34CrNiMo6 steel bars with transverse blind holes subjected to bending with torsion loading. The analysis of the geometric product specification was performed by means of height parameters Sx, functional volume parameters Vx, and fractal dimension Df. Surface topography measurements were carried out using an optical profilometer with focus variation technology....
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Two-dimensional simulations of concrete fracture at aggregate level with cohesive elements based on X-ray lCT images
PublicationThe paper presents results of two-dimensional meso-scale simulations of fracture in notched concrete beams subjected to three-point bending test. Concrete was assumed as a 4-phase material composed of aggregate grains placed in the cement matrix, interfacial transitional zones (ITZs) and macro-voids. The particle distribution was taken from real concrete beams on the basis of X-ray lCT images. Comprehensive numerical analyses were carried...
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Discrete element method simulations of fracture in concrete under uniaxial compression based on its real internal structure
PublicationThe paper describes experimental and numerical results of concrete fracture under quasi-static uniaxial compression. Experimental uniaxial compression tests were performed on concrete cubic specimens. Fracture in concrete was detected at the aggregate level by means of three non-destructive methods: three-dimensional X-ray microcomputed tomography, two-dimensional scanning electron microscope and manual two-dimensional digital...
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A three-dimensional meso-scale approach with cohesive elements to concrete fracture based on X-ray μCT images.
PublicationArtykuł omawia wyniki numeryczne dotyczące pękania betonu uzyskane stosując trójwymiarowy model mezoskopowy z elementami kohezyjnymi. Obliczenia trójwymiarowe zostały wykonane dla zginanej belki betonowej. Beton został opisany jako model 3-fazowy. Mikrostruktura betonu odpowiadała zdjęciom tomograficznym. Wyniki numeryczne zostały porównane z wynikami doświadczalnymi. Uzyskano b. dobra zgodność między wynikami numerycznymi i doświadczalnymi.