Repozytorium publikacji - Politechnika Gdańska

Ustawienia strony

english
Repozytorium publikacji
Politechniki Gdańskiej

Pokaż publikacje z roku

Ostatnie pozycje

  • Mało znane rozwiązania konstrukcyjne oraz funkcjonalno - użytkowe budynków w powojennej Gdyni Wybrane przykłady
    • Maciej Niedostatkiewicz
    2023

    Celem publikacji jest przedstawienie przykładów z realizacji budownictwa z lat 1950–1970, które świadczą o dużym zaangażowaniu zarówno projektantów, jak i wykonawców we wprowadzanie postępu technicznego w celu przyśpieszenia tempa realizacji inwestycji, co było działaniem priorytetowym w okresie odbudowy kraju ze zniszczeń będących następstwem II wojny światowej

  • Management of MV/LV Transformer Replacement Based on AMI Platform
    • Krzysztof Dobrzyński
    • Sławomir Noske
    • Dominik Falkowski
    2023 Automatyka Elektryka Zakłócenia

    The paper presents the extended possibilities of managing the selection and replacement of MV/LV transformers using the measurement data from the Advanced Metering Infrastructure (AMI) system. The analysis was conducted on samples of over 1900 transformers that operate in two different types of MV grids: rural and urban. The analysis has shown that there is a great potential in the field of optimizing the rated power of the transformers.

  • Management Strategy for Seaports Aspiring to Green Logistical Goals of IMO: Technology and Policy Solutions
    • Thanh Tuan Le
    • Hoang Phuong Nguyen
    • Krzysztof Rudzki
    • Lech Rowiński
    • Viet Duc Bui
    • Thanh Hai Truong
    • Huu Cuong Le
    • Nguyen Dang Khoa Pham
    2023 Pełny tekst Polish Maritime Research

    Recently, because of serious global challenges including the consumption of energy and climate change, there has been an increase in interest in the environmental effect of port operations and expansion. More interestingly, a strategic tendency in seaport advancement has been to manage the seaport system using a model which balances environmental volatility and economic development demands. An energy efficient management system is regarded as being vital for meeting the strict rules aimed at reducing the environmental pollution caused by port facility activities. Moreover, the enhanced supervision of port system operating methods and technical resolutions for energy utilisation also raise significant issues. In addition, low-carbon ports, as well as green port models, are becoming increasingly popular in seafaring nations. This study comprises a comprehensive assessment of operational methods, cutting-edge technologies for sustainable generation, storage, and transformation of energy, as well as systems of smart grid management, to develop a green seaport system, obtaining optimum operational efficiency and environmental protection. It is thought that using a holistic method and adaptive management, based on a framework of sustainable and green energy, could stimulate creative thinking, consensus building, and cooperation, as well as streamline the regulatory demands associated with port energy management. Although several aspects of sustainability and green energy could increase initial expenditure, they might result in significant life cycle savings due to decreased consumption of energy and output of emissions, as well as reduced operational and maintenance expenses

  • Mangiferin Affects Melanin Synthesis by an Influence on Tyrosinase: Inhibition, Mechanism of Action and Molecular Docking Studies
    • Anna Hering
    • Justyna Stefanowicz-Hajduk
    • Szymon Dziomba
    • Rafal Halasa
    • Radosław Krzemieniecki
    • Subrahmanyam Sappati
    • Maciej Baginski
    • Renata J. Ochocka
    2023 Pełny tekst Antioxidants

    Mangiferin is a strong antioxidant that presents a wide range of biological activities. The aim of this study was to evaluate, for the first time, the influence of mangiferin on tyrosinase, an enzyme responsible for melanin synthesis and the unwanted browning process of food. The research included both the kinetics and molecular interactions between tyrosinase and mangiferin. The research proved that mangiferin inhibits tyrosinase activity in a dose-dependent manner with IC50 290 +/− 6.04 µM, which was found comparable with the standard kojic acid (IC50 217.45 +/− 2.54 µM). The mechanism of inhibition was described as mixed inhibition. The interaction between tyrosinase enzyme and mangiferin was confirmed with capillary electrophoresis (CE). The analysis indicated the formation of two main, and four less significant complexes. These results have also been supported by the molecular docking studies. It was indicated that mangiferin binds to tyrosinase, similarly to L-DOPA molecule, both in the active center and peripheral site. As it was presented in molecular docking studies, mangiferin and L-DOPA molecules can interact in a similar way with surrounding amino acid residues of tyrosinase. Additionally, hydroxyl groups of mangiferin may interact with amino acids on the tyrosinase external surface causing non-specific interaction.

  • Mapping of Flood-Prone Areas Utilizing GIS Techniques and Remote Sensing: A Case Study of Duhok, Kurdistan Region of Iraq
    • Aumed M Amen
    • Andam Mustafa
    • Dalshad Ahmed Kareem
    • Hasan Mohammed Hameed
    • Ayub Anwar Mirza
    • Michał Szydłowski
    • Bala Kawa M. Saleem
    2023 Pełny tekst Remote Sensing

    One of the most common types of natural disaster, floods can happen anywhere on Earth, except in the polar regions. The severity of the damage caused by flooding can be reduced by putting proper management and protocols into place. Using remote sensing and a geospatial methodology, this study attempts to identify flood-vulnerable areas of the central district of Duhok, Iraq. The analytical hierarchy process (AHP) technique was used to give relative weights to 12 contributing parameters, including elevation, slope, distance from the river, rainfall, land use land cover, soil, lithology, topographic roughness index, topographic wetness index, aspect, the sediment transport index, and the stream power index in order to calculate the Flood Hazard Index (FHI). The relative importance of each criterion was revealed by a sensitivity analysis of the parameter values. This research developed a final flood susceptibility map and identified high-susceptible zones. This was classified anywhere from very low to very high classifications for its potential flood hazard. The generated map indicates that 44.72 km2 of the total land area of the study area in Duhok city has a very high susceptibility to flooding, and that these areas require significant attention from government authorities in order to reduce flood vulnerability

  • Mark Fisher. Dziwaczne i osobliwe. Przekład i posłowie: Andrzej Karalus i Tymon Adamczewski
    • Andrzej Karalus
    • Tymon Adamczewski
    2023

    Dziwaczne i osobliwe to zbiór esejów, w których autor dowodzi, że wiele spośród znanych dzieł kultury można opisać kategoriami dziwaczności lub osobliwości. Pojęcia te, choć bardzo do siebie zbliżone, nie są tożsame. Oba kojarzone są z horrorem lub literaturą sceince fiction, ale wykraczają poza jego ramy. Dotykają tego, co zewnętrzne i nieznane, niepokojące, ale niekoniecznie przerażające. Kategorie dziwaczności i osobliwości Fisher przykłada do dzieł takich twórców i twórczyń jak: H.P. Lovecraft, H.G. Wells, Daphne Du Maurier, Margaret Atwood, Stanley Kubrick czy Christoper Nolan. Ostatecznie otrzymujemy coś, co można by nazwać projektem "estetyki zewnętrza".

  • Mark Fisher: od hauntologii do estetyki zewnętrzności
    • Andrzej Karalus
    • Tymon Adamczewski
    2023

    W artykule zrekapitulowany zostaje projekt estetyki zewnętrza Marka Fishera, tak jak został zarysowany w artykułach i książce Dziwaczne i osobliwe. Artykuł osadza poszukiwania Fishera w szerszej ramie pojęciowej (w kontekście tzw. brytyjskiej teorii spekulatywno-kulturowej), jak i na tle wątków akceleracjonistycznych.

  • Mask Detection and Classification in Thermal Face Images
    • Natalia Kowalczyk
    • Milena Sobotka
    • Jacek Rumiński
    2023 Pełny tekst IEEE Access

    Face masks are recommended to reduce the transmission of many viruses, especially SARS-CoV-2. Therefore, the automatic detection of whether there is a mask on the face, what type of mask is worn, and how it is worn is an important research topic. In this work, the use of thermal imaging was considered to analyze the possibility of detecting (localizing) a mask on the face, as well as to check whether it is possible to classify the type of mask on the face. The previously proposed dataset of thermal images was extended and annotated with the description of a type of mask and a location of a mask within a face. Different deep learning models were adapted. The best model for face mask detection turned out to be the Yolov5 model in the “nano” version, reaching mAP higher than 97% and precision of about 95%. High accuracy was also obtained for mask type classification. The best results were obtained for the convolutional neural network model built on an autoencoder initially trained in the thermal image reconstruction problem. The pretrained encoder was used to train a classifier which achieved an accuracy of 91%.

  • MASTERPLAN SKUTECZNYM NARZĘDZIEM PLANOWANIA DZIELNIC
    • Weronika Mazurkiewicz
    2023 Przegląd Komunalny

    Przy równocześnie trwających pracach nad zmianą ustawy o planowaniu i zagospodarowaniu przestrzennym oraz niektórych innych ustaw wydaje się być zasadne poszukiwanie rozwiązań sprzyjających zahamowaniu dalszej degradacji przestrzeni niekoniecznie określonych ramami ustawowymi i prawem. Artykuł jest próbą ukazania zastosowania pozaustawowego dokumentu, jakim jest masterplan w polskich ramach planistycznych w celu kreowania spójnych wizji przestrzennych dla dzielnic i całościowych struktur przestrzennych. Od kilku lat toczy się dyskusja prowadzona przez samorządowców, urbanistów, środowiska naukowe, inwestorów i mieszkańców na temat zmian w systemie planowania przestrzennego oraz racjonalnej polityki przestrzennej w Polsce. Mamy też do czynienia zkryzysem przestrzennym narastającym od wielu lat, skutkującym m.in. rozlewaniem się miast, chaosem przestrzennym i rozproszeniem zabudowy, która często ma charakter niekompletny, gniazdowy i przypadkowy. Wydaje się, że propozycja zmiany ustawy o planowaniu i zagospodarowaniu przestrzennym w obecnej formie nie rozwiązuje wszystkich niedoskonałości prawa, szeroko komentowanych w ostatnich latach. Nie znaczy to jednak, że chaos przestrzenny musi dalej postępować. Jednym z rozwiązań stosowanych nieobligatoryjnie (niewymaganych ustawowo) jest stosowanie interdyscyplinarnych strategicznych dokumentów planistycznych, które określają zasady przygotowania i realizacji działań inwestycyjnych i nieinwestycyjnych. Wydaje się to być dobrym rozwiązaniem służącym kreowaniu elastycznych wizji rozwoju struktur przestrzennych oraz koordynacji kształtowania różnych dzielnic w mieście. Masterplan to najpopularniejsza nazwa dokumentu zawierającego kompleksową wizję danego terenu (spotykane nazwy narzędzi o podobnym zastosowaniu to m.in.: ministrategie rozwoju dzielnic, plany generalne dzielnic, strategie rozwoju dzielnic). Dokument ten od dawna jest stosowany w praktyce projektowej w Europie, w Polsce zaś stosunkowo krótko. Używane powszechnie za granicą nazwa, zawartość, forma oraz praktyka stosowania masterplanów to powód, dla którego w artykule wyróżniono tenże instrument spośród kilku innych o podobnym charakterze.

  • Materiały poliuretanowe o zmniejszonej palności otrzymane z udziałem biomasy ligninocelulozowej
    • Kamila Gosz
    2023 Pełny tekst

    Poliuretany są uniwersalnymi materiałami inżynierskimi o szerokim zakresie zastosowań, ponieważ ich właściwości można łatwo regulować stosując różne kombinacje składników. W ostatnich latach dużą uwagę zwraca się na efektywne wykorzystanie surowców ze źródeł odnawialnych jako substytutów dla zasobów kopalnych. Wynika to nie tylko z obaw o przyszłe braki w dostawach ropy naftowej, ale również z powodu większego zapotrzebowania na produkty bardziej przyjazne środowisku. Upłynniona biomasa ligninocelulozowa jest bogata w grupy hydroksylowe i uważa się, że może stanowić potencjalny surowiec do przygotowania żywic poliuretanowych. Z drugiej strony poliuretany są materiałem łatwopalnym. Opracowanie żywicy poliuretanowej z wykorzystaniem biomasy ligninocelulozowej o zmniejszonej palności stanowi bardzo ważny aspekt społeczny. W przedstawionej rozprawie doktorskiej jako środki zmniejszające palność wykorzystano włókno bazaltowe w postaci maty i uniepalniacz z wysoką zawartością fosforu co pozwoliło uzyskać uniepalnione materiały poliuretanowe o zadawalających właściwościach mechanicznych.

  • Mathematical modelling: Lessons from composite indicators
    • Marta Kuc-Czarnecka
    • Andrea Saltelli,
    2023

    We discuss here composite indicators as mathematical models, which can be looked at through the lenses of the five rules discussed in this volume. Composite indicators sit between analysis and advocacy, and their use has social and political implications. For this reason, the lenses of the manifesto can be used to build them better, to make them more transparent, as well as to inspect incumbent indicators for methodological or normative inadequacies.

  • Matrix Strengthening the Identification of Observations with Split Functional Models in the Squared Msplit(q) Estimation Process
    • Marek Zienkiewicz
    • Pawel S. Dąbrowski
    2023 MEASUREMENT

    This article addresses the issue of raising the level of identification of observations with either single or more split functional models in the squared Msplit(q) estimation process. The theoretical part of the study presents the theoretical grounds for the classical method for estimating parameters in a split functional model and proposes a modification of the computational algorithm to increase the quality of the determinations obtained. Theoretical considerations were verified through numerical tests concerning, e.g. issues of geodetic surveying practice and civil engineering.

  • Maximum transportation growth in energy and solute particles in Prandtl martial across a vertical 3D-heated surface: Simulations achieved using by finite element approach
    • Muhammad Bilal Hafeez
    • Marek Krawczuk
    • Wasim Jamshed
    2023 COMPUTERS & MATHEMATICS WITH APPLICATIONS

    The goal of this study is to determine the maximum energy and solute particles' transportation growth in a 3D-heated region of Prandtl martial through a dynamic magnetic field. The effects of this field on the properties of solvent molecules and heat conduction are studied. A correctly stated functional method and a finite element approach are comparable to a certain type of differential equations. In order demonstrate the effects of various factors such as mass diffusion, heat generation, and thermal diffusivity on the investigation of the diffusion coefficient and thermal mass in a three-dimensional Newtonian flow, the study of viscous and heat conduction rates is presented. The results show that the comparisons of hybrid nanofluid and with base fluid and w.r.t Local skin friction coefficient, Nusselt number and Sherwood number.

  • M-BDC (M = Co and/ or Fe) MOFs as effective catalysts for hydrogen generation via hydrolysis of sodium borohydride
    • Maria Alaide de Oliveira
    • Elibe Silva Souza
    • Jildimara de Jesus Santana
    • Natalia Łukasik
    • Bárbara Stefany Lima da Silva
    • Bráulio Silva Barros
    • Joanna Kulesza
    2023 APPLIED SURFACE SCIENCE

    Mono- (Co-BDC, Fe-BDC) and bimetallic FeCo-BDC Metal-Organic Frameworks are successfully synthesized by the solvothermal method in DMF at 150 °C within 15 h and tested as catalysts for sodium borohydride hydrolysis. The materials are characterized by FTIR, PXRD, TGA, ICP-OES, H2-TPR, BET model, and SEM-EDS. The catalytic activity of these materials is studied for dehydrogenation of sodium borohydride in water at various temperatures under basic conditions. Among tested catalysts, the most promising is Co-BDC, which provides hydrogen generation with a good rate of 1886.8 mL min−1 gcat−1 at 319 K and high efficiency (77.7 %) in the presence of a base. The activation energy determined as 25.4 kJ mol−1 is lower than most cobalt-bearing catalysts for NaBH4 hydrolysis described in the literature. The catalyst can be reused at least ten times, keeping a good overall hydrogen generation yield, and thus can be considered a promising candidate for portable hydrogen fuel systems.

  • Measuring the effectiveness of digital communication - social media performance: an example of the role played by AI-assisted tools at a university
    • Edyta Gołąb-Andrzejak
    2023 Pełny tekst

    The aim of the article is to show the role played by AI-powered tools in measuring the effectiveness of digital communication in social media using a university case study. Therefore, a research problem was formulated to identify the metrics (KPIs) used to measure the effectiveness – non-financial outcomes – of digital social media communication at the university using AI tools. The literature review on the role of AI in digital marketing in social media showed that it is used, inter alia, to measure the effectiveness of digital communication – social performance. The importance of KPIs in digital marketing – indicators for measuring non-financial performance – and the presentation of tools used to analyse the effectiveness of social media campaigns were based on a case study of a higher education institution in Poland. With the application of AI tools (such as ContentStudio, HelloWoofy or Sotrender etc.), it is possible to automate analytical processes for KPIs such as reach, engagement, content or customer service, among others, as well as systematic reporting. This, in turn, provides opportunities to systematically monitor and make improvements to the implemented social media marketing communication strategy – to create a kind of Decision Support System (DSS) to support the aforementioned process. The study is introductory and exploratory in nature. It indicates the importance of tools using AI in business practice – using the case study of a university as an example.

  • Mechanical and structural behavior of high-strength low-alloy steel pad welded by underwater wet welding conditions
    • Rassim Younes
    • Jacek Tomków
    • Idir Abdelhak
    • Mohand Amokrane Bradai
    2023 Pełny tekst INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY

    The aim of the paper was to determine the metallurgical and mechanical behaviors of a high-strength low-alloy (HSLA) steel pad-welded specimen used in the structures of industrial and naval parts. Then to predict the metallurgical consequences (nature of the phases present) and the mechanical properties (hardness and impact strength) of the pad-welded steel obtained by underwater wet welding with different heat input values. The XRD patterns clearly reveal a ferritic alpha steel S460N for both parameters. The ferritic quantification is above 70 wt% for low-alloy steel. The welded specimens are characterized by the presence of different phases. In a specimen performed with higher heat input, the complex oxide Mn2TiO4 was found to be around 7 wt%. Moreover, the solid solution formed with iron and manganese was observed. The hardness results obtained by indentation showed that the higher heat input resulted in higher hardness values (54 HRC) than for specimen performed with lower parameters (45 HRC). The impact test showed that the toughness of both pad-welded layers is greater than the toughness of the base material (40 kV for S2 and 34 kV for S1 about 27 kV for low-alloy steel). Moreover, it was observed that higher heat input results in increasing the impact strength of pad welds.

  • Mechanical Properties and Wear Susceptibility Determined by Nanoindentation Technique of Ti13Nb13Zr Titanium Alloy after “Direct Laser Writing”
    • Magdalena Jażdżewska
    • Beata Majkowska-Marzec
    • Andrzej Zieliński
    • Roman Ostrowski
    • Aleksandra Frączek
    • Gabriela Karwowska
    • Jean-marc Olive
    2023 Pełny tekst Materials

    Laser treatment has often been applied to rebuild the surface layer of titanium and its alloys destined for long-term implants. Such treatment has always been associated with forming melted and re-solidified thin surface layers. The process parameters of such laser treatment can be different, including the patterning of a surface by so-called direct writing. In this research, pulse laser treatment was performed on the Ti13Nb13Zr alloy surface, with the distance between adjacent laser paths ranging between 20 and 50 µm. The obtained periodic structures were tested to examine the effects of the scan distance on the microstructure using SEM, the roughness and chemical and phase composition using EDS and XRD, and the mechanical properties using the nanoindentation technique. After direct laser writing, the thickness of the melted layers was between 547 and 123 µm, and the surface roughness varied between 1.74 and 0.69 µm. An increase in hardness was observed after laser treatment. The highest hardness, 5.44 GPa, was obtained for the sample modified with a laser beam spacing of 50 µm. The value of the distance has been shown to be important for several properties and related to a complex microstructure of the thin surface layer close to and far from the laser path.

  • Mechanical Properties of Twisted Carbon Nanotube Bundles with Carbon Linkers from Molecular Dynamics Simulations
    • Andrea Pedrielli
    • Maurizio Dapor
    • Konstantinos Gkagkas
    • Simone Taioli
    • Nicola Maria Pugno
    2023 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    The manufacturing of high-modulus, high-strength fibers is of paramount importance for real-world, high-end applications. In this respect, carbon nanotubes represent the ideal candidates for realizing such fibers. However, their remarkable mechanical performance is difficult to bring up to the macroscale, due to the low load transfer within the fiber. A strategy to increase such load transfer is the introduction of chemical linkers connecting the units, which can be obtained, for example, using carbon ion-beam irradiation. In this work, we investigate, via molecular dynamics simulations, the mechanical properties of twisted nanotube bundles in which the linkers are composed of interstitial single carbon atoms. We find a significant interplay between the twist and the percentage of linkers. Finally, we evaluate the suitability of two different force fields for the description of these systems: the dihedral-angle-corrected registry-dependent potential, which we couple for non-bonded interaction with either the AIREBO potential or the screened potential ReboScr2. We show that both of these potentials show some shortcomings in the investigation of the mechanical properties of bundles with carbon linkers.

  • Mechanika kontaktu w charakteryzowaniu materiałów inżynierskich
    • Alicja Stanisławska
    2023

    W pierwszej części pracy przedstawiono teoretyczne podstawy mechaniki kontaktu. Omówiono model kontaktu Hertza opisujący zależność pomiędzy obciążeniem przyłożonym do kulistego wgłębnika i jego przemieszczeniem. W dalszej części scharakteryzowano modele niehertzowskie, w których pod uwagę bierze się siły adhezji. Przedstawiono dwa modele uwzględniające adhezyjne przyciąganie sferycznego wgłębnika i podłoża, tj. model Johnsona, Kendalla i Robertsa (JKR), wykorzystujący równowagę pomiędzy zmagazynowaną energią sprężystą a utratą energii powierzchniowej pomiędzy kulistym wgłębnikiem i powierzchnią płaską, oraz model sprężystego kontaktu Derjaguina–Mullera–Toporowa (DMT). Model JKR uwzględnia wpływ nacisku kontaktowego i adhezji tylko wewnątrz obszaru kontaktu, natomiast model DMT uwzględnia dodatkowo siły przyciągania występujące pomiędzy ciałami, które oddziałują także poza strefą kontaktu. W dalszej części monografii zaprezentowano modele dla płaskich powierzchni biorące pod uwagę ich chropowatość. Opisano teorię Greenwooda i Williamsona (GW), która zakłada, że wysokości nierówności mają rozkład gaussowski, a odkształcenie nierówności jest opisane modelem Hertza, oraz teorie Greenwooda i Trippa. Następnie przedstawiono matematyczny opis odkształcania materiału przy jego kontakcie z wgłębnikiem w kształcie stożka, zaprezentowany przez Sneddona. W kolejnym rozdziale omówiono różne metody pomiaru twardości materiałów: Brinella, Meyera, Vickersa, Knoopa, Martensa i Rockwella. Następny rozdział opisuje metodę indentacji. Scharakteryzowano w nim naprężenia i odkształcenia w materiale podczas penetracji przez kulisty i ostry wgłębnik, sposoby określania twardości i sztywności materiału, opisano efekt skali występujący dla małych przemieszczeń wgłębnika, a także sposób wyznaczania gęstości dyslokacji występujących w materiale i ich mobilności. Rozdział ten zawiera też omówienie sposobu wyznaczania współczynnika umocnienia odkształceniowego, krytycznego współczynnika intensywności naprężeń oraz naprężeń własnych przy wykorzystaniu testu indentacji. Znajdują się tu również informacje na temat testu zarysowania. Ostatni rozdział przedstawia wyniki prac naukowych, których autorka jest współautorem, i wyniki badań własnych jeszcze nieopublikowanych, które zostały uzyskane za pomocą indentera.

  • Mechanism of antifreeze protein functioning and the “anchored clathrate water” concept
    • Jan Zielkiewicz
    2023 Pełny tekst JOURNAL OF CHEMICAL PHYSICS

    In liquid water, there is a natural tendency to form aggregates that consist of water molecules linked by hydrogen bonds. Such spontaneously formed aggregates are surrounded by a "sea" of disordered water molecules, with both forms remaining in equilibrium. The process of creating water aggregates also takes place in the solvation water of proteins, but in this case the interactions of water molecules with the protein surface shift the equilibrium of the process. In this paper, we analyze the structural properties of the solvation water in antifreeze proteins (AFPs). The results of molecular dynamics analysis with the use of various parameters related to the structure of solvation water on the protein surface are presented. We found that in the vicinity of the active region responsible for the binding of AFPs to ice, the equilibrium is clearly shifted towards the formation of "ice-like aggregates", and the solvation water has a more ordered ice-like structure. We have demonstrated that a reduction in the tendency to create "ice-like aggregates" results in a significant reduction in the antifreeze activity of the protein. We conclude that shifting the equilibrium in favor of the formation of "ice-like aggregates" in the solvation water in the active region is a prerequisite for the biological functionality of AFPs, at least for AFPs having a well-defined ice binding area. Also, our results fully confirm the validity of the "anchored clathrate water" concept, formulated by Garnham et al. (PNAS, (2011), 108, 7363).

  • Mechanochemically synthesized Mn3O4@β-cyclodextrin mediates efficient electron transfer process for peroxymonosulfate activation
    • Huan Liu
    • Xiaohui Dai
    • Lingshuai Kong
    • Meng Xie
    • Chengji Sui
    • Qianyi Zhang
    • Grzegorz Boczkaj
    • Przemysław Kowal
    • Bin Cai
    • Jinhua Zhan
    2023 SEPARATION AND PURIFICATION TECHNOLOGY

    The rational surface engineering of heterogeneous catalysts is of great significance in advanced oxidation processes (AOPs) for eliminating refractory contaminants but remains challenging. In this study, β-cyclodextrin modified Mn3O4 (Mn3O4@β-CD) was prepared through a mechanochemical approach for peroxymonosulfate (PMS) activation, which achieved efficient bisphenol A (BPA) removal via electron transfer process (ETP). The reactive PMS* complex with elevated potential was identified to dominate the ETP by withdrawing electrons from BPA with Mn3O4@β-CD working as electron shuttle, as evidenced by spectroscopy and electrochemical techniques. Experimental results and density functional theory (DFT) calculations showed that the β-CD modification enhanced the interfacial accumulation of pollutants and shortened the migration distance between pollutants (electron donor) and catalysts (electron shuttle) to mediate electron transfer more effectively. Benefitting from the improved ETP, the Mn3O4@β-CD/PMS system showed efficient PMS utilization and practical adaptability in actual waterbodies. This study provides a rational approach for modulating the surface structure of heterogeneous catalysts in PMS-based AOPs for environmental remediation.

  • Membrane distillation assisting food production processes of thermally sensitive food liquid items: a review
    • Emilia Gontarek-Castro
    • Roberto Castro Muñoz
    2023 Pełny tekst CRITICAL REVIEWS IN FOOD SCIENCE AND NUTRITION

    Physical separation technologies have become important tool for processing in the current food manufacturing industries, especially for the products containing bioactive compounds thanks to their health benefits in costumers. As for the processing of bioactive food ingredients implies the implementation of integrated systems oriented to their separation, fractionation, and recovery. In this field, membrane distillation (MD), which is a thermally driven membrane process, has been proposed as an alternative for the separation and concentration of liquid food items. In principle, MD can separate water and volatile compounds from aqueous feed solutions through a permeate that passes across microporous hydrophobic membranes. The separation via MD is thanks to the vapor pressure difference on both membrane sides. In this review, we analyzed the ongoing experimental efforts aimed to recover and purify food bioactive compounds from the concentration of fruit juices and extracts using MD. Also, the processing of dairy products, concentration of food by-products, and ethanol production and its removal from beverages using MD have been reviewed. Additionally, a feedback on the distinct membrane module configurations and membrane requirements for successful operation is addressed.

  • Merging Proline:Xylitol Eutectic Solvent in Crosslinked Chitosan Pervaporation Membranes for Enhanced Water Permeation in Dehydrating Ethanol
    • Roberto Castro Munoz
    • Maksymilian Plata-Gryl
    • Grzegorz Boczkaj
    2023 Pełny tekst Membranes

    The scope of this research aims at merging a new deep eutectic mixture (DES) into a biopolymer-based membrane for a pervaporation application in dehydrating ethanol. Herein, an L-proline:xylitol (at 5:1) eutectic mixture was successfully synthesized and blended with chitosan (CS). A complete characterization of the hybrid membranes, in terms of morphology, solvent uptake, and hydrophilicity, has been conducted. As part of their applicability, the blended membranes were assayed for their ability to separate water from ethanolic solutions by means of pervaporation. At the highest temperature (50 °C), a water permeation of ca. 0.46 kg m−2 h−1 was acquired, representing a higher permeation than the pristine CS membranes (ca. 0.37 kg m−2 h−1). Therefore, CS membranes demonstrated an enhanced water permeation thanks to their blending with the hydrophilic L-proline:xylitol agent, making these membranes a good candidate for other separations containing polar solvents.

  • Metaliczne nanostruktury i nanostopy na bazie Au i Ag
    • Robert Kozioł
    2023 Pełny tekst

    W niniejszej rozprawie doktorskiej opisano kontrolowane otrzymywanie metalicznych nanostruktur ze złota i srebra, o pożądanych właściwościach optycznych, w wyniku odwilżania termicznego ultracienkich warstw metalicznych. Pokazano w niej wpływ poszczególnych parametrów wytwarzania na końcowo uzyskiwane właściwości nanostruktur plazmonicznych. Dodatkowo, zaprezentowano skuteczność stosowanej preparatyki w otrzymywaniu jednorodnych nanostruktur stopowych, których właściwości optyczne, w konsekwencji kontroli nad zachodzącymi efektami synergistycznymi, były modulowane w zakresie 100 nm wewnątrz widma światła widzialnego. Co więcej, zaprezentowano również potencjalne zastosowanie otrzymywanych w ten sposób nanostruktur jako czujników w środowiskach ciekłych, demonstrując tym samym ich stabilność. Dodatkowo, zaimplementowano techniki z obszaru technologii informatycznej: symulacje metodą różnic skończonych w dziedzinie czasu do wyznaczenia rozkładu pól elektromagnetycznych w płaszczyźnie wytworzonych nanostruktur; oraz uczenia maszynowego celem predykcji wymaganych parametrów syntezy nanostruktur o żądanych właściwościach optycznych.

  • Metallurgical characterization and high-temperature tensile failure of Inconel 617 alloy welded by GTAW and SMAW—a comparative study
    • Sachin Sirohi
    • Naveen Kumar
    • Amit Kumar
    • Shailesh M. Pandey
    • Balamurugan Adhithan
    • Dariusz Fydrych
    • Chandan Pandey
    2023 PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART L-JOURNAL OF MATERIALS-DESIGN AND APPLICATIONS

    Two types of the weld joint of Inconel 617 alloy were produced using gas tungsten arc welding (GTAW) and shielded metal arc welding (SMAW) processes with ERNiCrCoMo-1 filler metal and ENiCrCoMo-1 electrode, respectively. The weld metal showed the segregation of the principle alloying elements like Mo and Cr along the inter-dendritic spaces, triggering the formation of secondary phases. The microstructure characterization of the interface ensured the high dilution, which could be attributed to the closeness in melting point and chemistry of base and filler metal. Microhardness variation, tensile testing at room and high temperature, and Charpy impact test were conducted to investigate the effect of the Mo segregation in the weld zone and heterogeneity in the microstructure of weldments on the mechanical behavior of both the welded joints. The cross-weld tensile tests were conducted at room temperature and 550°C. The tensile test samples failed from the weld zone for each condition with a tensile strength value close to the base metal, which ensured the applicability of the joint for end service. The tensile strength of GTAW-RT, GTAW-HT, SMAW-RT, and SMAW-HT were measured as 766 ± 22 MPa, 570 ± 5 MPa, 760 ± 7 MPa, and 600 ± 8 MPa, respectively. A non-uniform hardness plot was witnessed with the hardness of the GTAW-weld and SMAW-weld zone of 257 ± 8 HV and 285 ± 5 HV, respectively, in the transverse direction. The impact toughness of the weld zone was 84 ± 2 J and 48 ± 4 J for GTAW and SMAW weld zone. The average impact toughness of the GTAW-weld zone was approximately 42% higher than the value of the SMAW-weld zone. In a nutshell, it can be concluded that the welded joint of Inconel 617 produced using the GTAW process with ERNiCrCoMo-1 filler had the best metallurgical and mechanical properties.

  • Metal-Organic Frameworks in Green Analytical Chemistry
    • Justyna Płotka-Wasylka
    • Małgorzata Rutkowska
    • Natalia Jatkowska
    • Zeraati Malihe
    • Sargaze Ghasem
    • Massoud Kaykhaii
    2023 Pełny tekst

    Taking into consideration the rapid expansion of MOFs applications in the analytical chemistry area, it is important to evaluate the existing and future analytical MOF-based methods according to GAC principles. From this point of view, eco-friendly MOFs-based methods should include features such as: green design and synthesis of MOF, evaluation of toxicity issues of MOFs, and incorporation of MOFs in GAC methods. This Chapter will put particular emphasis on the efforts made on greener synthesis of MOFs and the various routes and methods explored in this regard. In addition, their incorporation into less-harmful analytical chemistry methods is discussed.

  • Metamaterial-Based Series-Fed Antenna with High Gain and Wideband Performance for Millimeter Wave Spectrum Applications
    • Bashar Esmail
    • Sławomir Kozieł
    • Dustin Isleifson
    2023 Pełny tekst Electronics

    This paper presents a high-gain, wideband series-fed antenna designed for 5G millimeter-wave (MMW) applications. The structure employs a substrate-integrated waveguide (SIW)-based power splitter and metamaterials (MMs). The power divider functions effectively at 27.5 GHz, exhibiting an impedance bandwidth from 26.9–28.6 GHz. The series-fed dipole is assembled on the SIW-based power splitter, incorporating four dipoles with varying lengths and spacing. The di-poles are connected in series on both sides, running in parallel through a microstrip line. Effec-tively combining the resonances of the series-fed dipoles and the SIW results in a broad imped-ance bandwidth, ranging from 26.9 GHz to 34.75 GHz. The design offers a gain extending from 9 to 10.5 dBi within the operating bandwidth. To improve gain performance without a substantial increase in antenna size, 11 × 6 MM unit cells have been positioned in front of the antenna. As a result, the proposed antenna achieves a maximum gain of 14.1 dBi at 30.5 GHz while maintaining an operational bandwidth of 7.85 GHz. Additionally, due to the arrangement of the MM-based two series-fed dipoles, the antenna exhibits symmetrical dual-beam E-plane radiation at ±20° at 28 GHz in the end-fire direction. The developed system was experimentally validated and demon-strated excellent agreement between the simulated and measured data.

  • Method for determining of shallow water depths based on data recorded by UAV/USV vehicles and processed using the SVR algorithm
    • Mariusz Specht
    • Bartosz Szostak
    • Oktawia Lewicka
    • Andrzej Stateczny
    • Cezary Specht
    2023 MEASUREMENT

    Bathymetric measurements in waters shallower than 1 m are necessary to monitor seafloor relief changes in the coastal zone. This is especially important for ensuring the safety of navigation, navigation efficiency, as well as during the design and monitoring of hydrotechnical structures. Therefore, the aim of this article is to present a method for determining of shallow water depths based on data recorded by Unmanned Aerial Vehicle (UAV) and Unmanned Surface Vehicle (USV), as well as processed using the Support Vector Regression (SVR) algorithm. Validation studies of this method was carried out on two selected waterbodies (inland and sea) using the DJI Phantom 4 Real Time Kinematic (RTK) UAV and the AutoDron USV. Then, the geospatial data recorded by a drone was applied to determine depths of shallow waterbodies using the SfM algorithm. Subsequently, the determined depths were compared with the depths measured by a Global Navigation Satellite System (GNSS) RTK receiver or a Single Beam Echo Sounder (SBES), in order to assess the accuracy of the proposed method. The research showed that it is able to determine shallow waterbody depths with the accuracy requirements specified for the International Hydrographic Organization (IHO) S-44 special order (depth error ≤ 0.25 m (p = 0.95)), but only to depths not exceeding 1 m. In the inland waterbody, the depth accuracy was 0.22–0.24 m (p = 0.95), while in the sea waterbody the measurement accuracy was higher, amounting to 0.16 m (p = 0.95). However, for the depth range up to 2 m, the results are radically different, because the vertical position error with a 95% confidence level exceeds the value of 0.3 m in the analysed waterbodies.

  • Methodology for Performing Bathymetric Measurements of Shallow Waterbodies Using an UAV, and their Processing Based on the SVR Algorithm
    • Bartosz Szostak
    • Mariusz Specht
    • Paweł Burdziakowski
    • Andrzej Stateczny
    • Cezary Specht
    • Oktawia Lewicka
    2023 MEASUREMENT

    State-of-art methods of bathymetric measurements for shallow waterbodies use Global Navigation Satellite System (GNSS) receiver, bathymetric Light Detection and Ranging (LiDAR) sensor or satellite imagery. Currently, photogrammetric methods with the application of Unmanned Aerial Vehicles (UAV) are gathering great importance. This publication aims to present step-by-step methodology for carrying out the bathymetric measurements of shallow waterbodies with the use of UAV-Structure from Motion (SfM) and Support Vector Regression (SVR) algorithms. Proposed model is explained and verified on the basis of measurement campaign on Raduńskie Górne Lake located in Poland. The campaign included GNSS Real Time Kinematic (RTK) bathymetric measurements for robust training dataset and photogrammetric flight pass for SfM point cloud. The presented methodology will allow to perform bathymetric measurements with the accuracy provided for the International Hydrographic Organization (IHO) Special Order (horizontal position error ≤ 2 m (p=0.95), vertical position error ≤ 0.25 m (p=0.95)).

  • Methodology for Performing Bathymetric Measurements of Shallow Waterbodies Using an UAV, and their Processing Based on the SVR Algorithm
    • Bartosz Szostak
    • Mariusz Specht
    • Paweł Burdziakowski
    • Andrzej Stateczny
    • Cezary Specht
    • Oktawia Lewicka
    2023 MEASUREMENT

    State-of-art methods of bathymetric measurements for shallow waterbodies use Global Navigation Satellite System (GNSS) receiver, bathymetric Light Detection and Ranging (LiDAR) sensor or satellite imagery. Currently, photogrammetric methods with the application of Unmanned Aerial Vehicles (UAV) are gathering great importance. This publication aims to present step-by-step methodology for carrying out the bathymetric measurements of shallow waterbodies with the use of UAV-Structure from Motion (SfM) and Support Vector Regression (SVR) algorithms. Proposed model is explained and verified on the basis of measurement campaign on Raduńskie Górne Lake located in Poland. The campaign included GNSS Real Time Kinematic (RTK) bathymetric measurements for robust training dataset and photogrammetric flight pass for SfM point cloud. The presented methodology will allow to perform bathymetric measurements with the accuracy provided for the International Hydrographic Organization (IHO) Special Order (horizontal position error ≤ 2 m (p=0.95), vertical position error ≤ 0.25 m (p=0.95)).

  • Methodology of experimental research on efficiency of hydro-mechanical automatic gearbox
    • Piotr Patrosz
    • Paweł Załuski
    • Marcin Bąk
    • Paweł Śliwiński
    • Mykola Karpenko
    2023 Pełny tekst

    The article shortly describes the design and principle of operation of the hydromechanical gearbox and presents the methodology and design of test stands used for testing hydromechanical proto-type gearbox developed at Technical University of Gdansk. The article presents an approach according to which, in order to obtain reliable measurement data, it is necessary to separate the tests of the hydraulic and mechanical parts of the gearbox. For this reason, the tests of the pump and the hydraulic motor are also presented. To validate this approach sample test results are in-cluded and discussed.

  • Methods of Cyclist Training in Europe
    • Joanna Wachnicka
    • Alicja Jarczewska
    • Giuseppina Pappalardo
    2023 Pełny tekst Sustainability

    The following study aims to address the issue of cyclist training methodologies. Recent European bicycle accident statistics reveal a troubling upward trend. A potential solution to mitigate such incidents involves providing cyclists with comprehensive training encompassing traffic regulations and interactions with fellow road users. We conducted a comparative analysis of the cycling education approaches and cyclist training systems in several countries, including the Netherlands, Germany, Austria, England, Slovenia, Poland, and Italy. This analysis underscored the importance of standardizing training protocols and criteria across Europe. The training model should draw inspiration from countries with well-established cycling cultures and serve as a foundation for harmonizing training practices.

  • Metoda diagnostyki cieplno-przepływowej turbin parowych wykorzystująca elementy algorytmów genetycznych
    • Marta Drosińska-Komor
    2023 Pełny tekst

    Rozprawa doktorska poświęcona jest opisowi budowania metody diagnostyki cieplno-przepływowej z wykorzystaniem elementów algorytmów genetycznych. Do tworzenia założeń i algorytmów metody posłużono się przykładem funkcjonowania bloku elektrowni kondensacyjnej ze szczególnym uwzględnieniem układu łopatkowego turbiny parowej. Celem pracy jest zbudowanie metody diagnostyki cieplno-przepływowej. Zadaniem metody jest przeprowadzenie procesu diagnozy dla pogorszonych parametrów eksploatacyjnych procesu przemian energetycznych bloku energetycznego (np. sprawności) polegająca na detekcji, lokalizacji i identyfikacji przyczyn degradacji urządzeń składowych bloku energetycznego. Motywacją do podjęcia badań jest coraz ważniejsza rola procedur diagnostycznych w eksploatacji obiektów energetycznych Zbudowana w trakcie pracy kwalifikacyjnej metoda diagnostyczna poszukiwania niesprawności i uszkodzeń jest przewidziana do użycia tylko w procedowaniu off-line. Badania nad zastosowaniem metod algorytmów genetycznych dla celów diagnostyki cieplno-przepływowej pokazały, że nie można użyć klasycznego algorytmu genetycznego do wykrywania degradacji wielokrotnych. Intensywne badania wykorzystujące symulacje degradacji eksploatacyjnej turbin doprowadziły do modyfikacji jednego z elementów algorytmu genetycznego – procesu selekcji. Wyniki badań umożliwiły zbudowanie nowej metody diagnostycznej pozwalającej na przeprowadzenie z dobrą dokładnością procesu lokalizacji i identyfikacji przyczyn degradacji wielokrotnych występujących potencjalnie w turbinach parowych.

  • Metoda obliczania skutków wdrożenia strategii zarządzania popytem na energię elektryczną (DSM/DSR) w systemach elektroenergetycznych
    • Wiktoria Stahl
    2023 Pełny tekst

    W niniejszej rozprawie poruszono zagadnienie strategii zarządzania popytem na energię elektryczną (DSM/DSR) i sposobów obliczania efektów ich wdrożenia. W związku z tym opisano oczekiwane efekty wdrożenia tych rozwiązań oraz ich zalety i wady. Zaprezentowano i przeanalizowano istniejące już metody obliczania skutków wdrożenia DSM/DSR. Zaproponowano nową metodę, która poprzez formę algorytmu uporządkowuje proces obliczania i oceny efektów realizacji tych rozwiązań. W ramach metody zaproponowano także zestaw wskaźników opisujących efekty wdrożenia DSM/DSR. Ponadto, metoda pozwala na symulowanie i prognozowanie spodziewanych rezultatów poprzez wykorzystanie symulacji Monte Carlo i modelów ekonometrycznych. Przy pomocy modeli, przedstawiono także czynniki mogące mieć wpływ na powodzenie realizacji strategii zarządzania popytem. W rozprawie przedstawiono również przykład obliczeniowy z wykorzystaniem zaproponowanej metody. Przykład oparty jest na zgromadzonych danych dotyczących preferencji odbiorców w sprawie realizacji strategii zarządzania popytem na energię elektryczną. W ramach obliczeń symulacyjnych przedstawiono potencjał realizacji rozwiązań DSM/DSR w Polsce.

  • Metodologia i metodyka odtworzenia stolarki okiennej w zabytkowych obiektach na przykładzie Muzeum Bursztynu w Wielkim Młynie w Gdańsku
    • Ksenia Piątkowska
    • Elżbieta Ratajczyk-Piątkowska
    • Katarzyna Darecka
    2023 Pełny tekst Wiadomości Konserwatorskie

    W artykule przedstawiono metodologię i metodykę odtworzenia stolarki okiennej w obiekcie zabytkowym, o zachowanej średniowiecznej formie, przy realizacji Muzeum Bursztynu w Wielkim Młynie w Gdańsku. Omówiono wyniki wykonanych badań w tym zakresie i decyzje projektowe odtworzenia okien. Opisano wpływ współczesnych wymagań dotyczących stolarki w obiektach muzealnych na jej kształt i formę. Wykonane dla Muzeum Bursztynu okna są autorską syntezą historii Wielkiego Młyna przedstawiającą współcześnie elewacje ze stolarką okienną w konfiguracji, w której prawdopodobnie nigdy nie istniała, ale która w pełni ilustruje jego przeszłość zgodnie z obecnym stanem wiedzy na temat faz rozwoju obiektu oraz obowiązujących wymagań techniczno-użytkowych.

  • Metody generowania energii
    • Ewa Klugmann-Radziemska
    • Katarzyna Januszewicz
    2023

    Generowanie energii stanowi podstawę funkcjonowania społeczeństw i rozwoju gospodarki światowej. W różnych krajach kluczowe technologie, na których opiera się energetyka, są inne, co zależy zarówno od historycznych podstaw rozwoju tego sektora, postępu technicznego, jak i uwarunkowań politycznych, a co za tym idzie – legislacyjnych. W krajach Unii Europejskiej od wielu lat dominuje trend rozwoju energetyki opartej na źródłach odnawialnych. Jest to często trudne do pogodzenia z istniejącymi rozwiązaniami, gdy – tak jak w naszym kraju – przeważa energetyka oparta na węglu. W krajach wysoko rozwiniętych świadoma polityka państw zaowocowała rozwojem energetyki wiatrowej, słonecznej czy jądrowej. W bilansie niektórych krajów zagospodarowanie energetyczne odpadów stanowi nie tylko uzupełnienie niedoborów paliwowych, lecz także skuteczny sposób pozbycia się tego niewygodnego problemu. Wszystkie omówione w rozdziale technologie pozyskiwania energii elektrycznej i ciepła należy rozważać w ścisłym powiązaniu z polityką zrównoważonego rozwoju i ochroną środowiska, stanowi on więc niejako wprowadzenie do kolejnych rozdziałów.

  • Metody wzmacniania krótkich wsporników słupa w świetle badań eksperymentalnych
    • Krystyna Nagrodzka-Godycka
    2023 Inżynieria i Budownictwo

    W artykule podano metody wzmacniania wsporników słupów, których skuteczność została zweryfikowana badaniami eksperymentalnymi. Niezależnie od zastosowanej metody efektywność wzmocnienia wspornika jest głównie uzależniona od smukłości ścinania wspornika, ilości zbrojenia wewnętrznego i jego wytężenia przed wzmocnieniem.

  • Miasto w działaniu. Nowe pola aktywności społecznej
    • Małgorzata Dymnicka
    • Jarosław Załęcki
    2023

    Miasto od wieków jest areną sporów, przestrzenią konfliktów i miejscem uzgadniania interesów. Już sama relacja mieszkańców z miastem polega na konstytuowaniu przestrzeni, organizacji i reorganizacji współistnienia. Oznacza to, że od socjologicznie rozumianej przestrzeni należy oczekiwać, że uchwyci ona społeczny proces stanowienia. Przestrzeń miasta, w obrębie której żyje dana społeczność, jest jednym z najważniejszych obszarów oddziaływania ze względu na niedostatki, ograniczenia i bariery w dostępie do zasobów. Politycy miast i wielokulturowych metropolii coraz częściej zdają sobie sprawę, że ich zadaniem jest minimalizowanie napięć pomiędzy wyobrażoną wspólnotą podzielanych (lokalnych) tożsamości a konstruującymi ją regułami prawnymi. Można przywołać wiele przykładów, które obrazują skuteczne działania na rzecz zmiany rzeczywistości, jako dowód na aktywność zwyczajnych i niekoniecznie najbardziej zaawansowanych w sztuce życia obywatelskiego i społecznego obywateli, którzy korzystają z prawa i wolności do określonych działań na rzecz szeroko pojętego środowiska zbudowanego.

  • Micro‑ and nano‑ bentonite to improve the strength of clayey sand as a nano soil‑improvement technique
    • Mohadeseh Cheraghalikhani
    • Hamed Niroumand,
    • Lech Bałachowski
    2023 Pełny tekst Scientific Reports

    Nano-additives results in the formation of nano-cementation (NC). This process is recently used to improve the durability of various building materials. NC used to improve the strength of untreated soil materials, also known as nano soil-improvement (NSI). In few years, the role of nano-additives in various types of soils were developed. In this research, the role of micro- and nano- size of bentonite as soil stabilizer was evaluated as first few research to improve geotechnical properties of soils. Nanoadditives prepared by micro- and nano- sizes of bentonite were blend with four formulations. These formulations of micro- and nano- additives at concentrations of 0, 1, 2, and 3%, namely 0% Micro- Bentonite, 1% Micro-Bentonite, 2% Micro-Bentonite, 3% Micro-Bentonite, 0% Nano-Bentonite, 1% Nano-Bentonite, 2% Nano-Bentonite, and 3% Nano-Bentonite, respectively. These formulations of micro- and nano- additives were separately added to soil. Specimens with 3% nano-bentonite showed significant improvement in unconfined compressive strength (UCS) of soil that was more than 2.3-times higher than control specimen in 7-d curing time. Also the performance of micro-bentonite resulted in improvement in UCS of soil that was more than 1.1-times higher than control specimen at 7-d curing time. The secant modulus at 50% of peak stress (E50) of the samples treated with microand nano- additives increased in comparison to untreated specimens. Further, X-ray fluorescence (XRF), scanning electron microscopy, and X-ray diffraction analyses characterized micro- and nanostructures of soil specimens, and showed the performance of nano-additives in improving strength of soils. Results show that nano-bentonite as a type of nano-additives is an effective means of increasing the strength of soils. This research shows the significant of nano-bentonite in soil improvement, as a NSI technique.

  • Microbiota-derived metabolites in colorectal cancer patients in preoperative period
    • Karolina Każmierczak-Siedlecka
    • K. Skonieczna-Żydecka
    • J. Palma
    • Bartosz Kamil Sobocki
    • M. Świerblewski
    • K. Siedlecka-Kroplewska
    • Leszek Kalinowski
    • K. Połom
    2023 Pełny tekst European Review for Medical and Pharmacological Sciences

    Short-chain fat-ty acids (SCFAs) are microbial derived metabo-lites, which have multiple beneficial properties. The amount of SCFAs depends on several fac-tors, such as age, diet (mainly intake of dietary fiber), and overall health condition. The normal proportion between SCFAs is 3:1:1 for acetate, proprionate and butyrate, respectively. In col-orectal cancer (CRC) patients, microbiota alter-ations have been shown. Consequently, metab-olome within the gut might change to a large ex-tent. Therefore, the aim of this study was to anal-yse the content of SCFAs and the proportion be-tween SCFAs in the stool obtained from CRC pa-tients in preoperative period. PATIENTS AND METHODS: This study in-cluded 15 patients with CRC in preoperative pe-riod. The stool samples were taken and stored at -80°C in the Fahrenheit Biobank BBMRI.pl, Med-ical University of Gdansk, Poland. The analysis of SCFAs from stool samples was conducted by means of gas chromatography. RESULTS: This study included mainly males (66.67%, n=10). In all patients, there was abnor-mal proportion between SCFAs. The extreme-ly higher concentration of butyrate was noted in 2 samples (13.33%) compared to the rest of pa-tients. However, based on normal proportion be-tween SCFAs, the results <1 for butyrate were noted in 93.33% of patients. CONCLUSIONS: SCFAs pool is altered in CRC patients, among others characterized by low level of butyrate. It should be considered to administer butyrate supplementation to CRC pa-tients especially prior to surgery to support an appropriate preparation to this treatment.

  • Microcrack monitoring and fracture evolution of polyolefin and steel fibre concrete beams using integrated acoustic emission and digital image correlation techniques
    • Shahzad Ashraf
    • Magdalena Rucka
    2023 Pełny tekst CONSTRUCTION AND BUILDING MATERIALS

    The use of polymer and steel fibres in plain concrete appears to be an excellent solution for limiting crack propagation and improving the post-ductility performance of concrete structures. Based on this premise, this study investigated the fracture evolution of polyolefin fibre-reinforced concrete (PFRC) and steel fibre-reinforced concrete (SFRC) specimens through the integrated application of two diagnostic techniques, acoustic emission (AE) and digital image correlation (DIC), under three-point bending tests. Based on the processing of AE signals, different AE statistical parameters such as the cumulative number of hits, amplitude distribution, and some representative analysis methods including the b-value method, Ib-value method, and AE intensity analysis methods were selected to analyse the early detection of cracking and post-cracking behaviour in PFRC vs SFRC specimens during mechanical degradation. Simultaneously, the DIC technique was used to validate the fracture evolution of the AE results. Furthermore, to verify the reliability of the AE and DIC results, the damage localisation and fracture evolution of the PFRC versus SFRC specimens were confirmed by integrating the AE fracture energies and DIC outcomes. The tests and analysed results showed that the addition of steel fibres to plain concrete significantly improved the ability to restrict crack propagation and provided higher post-cracking resistance compared to PFRC specimens owing to their stronger fibre-matrix bonding, effective fibre bridging, and crack-arresting mechanism. The present study indicates that the combined AE and DIC techniques are highly effective for the early detection of damage and ductility performance in fibre-reinforced concrete structures.

  • Microcracking monitoring and damage detection of graphene nanoplatelets-cement composites based on acoustic emission technology
    • Shahzad Ashraf
    • Suliman Khan
    • Vipin Kumar Oad
    2023 Pełny tekst Case Studies in Construction Materials

    This study aims to identify the micro-cracking pattern and structural applications of cement composites replaced with 0 wt%, 0.04 wt%, and 0.08 wt% contents of graphene nanoplatelets (GNPs) over cement weight through acoustic emission (AE) monitoring under mechanical degradation. The ultraviolet-visible spectroscopy (UV–vis) results showed that at 60 min sonication period, GNP-4 showed maximum absorbance rate of 16.15% compared to the GNP-8. The microstructural characteristics revealed that during hydration of cement there was no apparent cracks appeared in GNPs-cement composites compared to the reference specimen (GNP-0) which was 1.44 mm. The cracking mode and damaged detection of the tested specimens resulted in three distinct stages i.e., (I) pre-peak, (II) peak, and (III) post-peak under mechanical degradation. GNP-4 achieved 780 N flexural capacity which was increased by 30% and 21.87% compared to the GNP-0 and GNP-8. Similarly, a compressive strength of 63.12 MPa, 57.5 MPa, and 56 MPa at 28 days was obtained by GNP-4, GNP-8, and GNP-0, respectively. Based on AE hits and amplitude analysis, the resistance to fracture, damping capacity, and ductility of GNP-4 was improved by 25.30%, 25.1%, and 22.47% respectively, to that of GNP-0. Shear failure (>35 kHz) was observed in GNP-0, while GNPs cement composites recorded tensile failure (<35 kHz) through RA-AF parameters. The cracking pattern through Ib value with a warning sign of 1.5 between micro and macro-cracks and severity of damages through historical index (HI) and severity index (Sr) of GNPs cement composites was determined. Lastly, it was concluded that GNPs contents can significantly improve bending strength and delay the cracks initiation in cement composites.

  • Microemulsion Delivery Systems with Low Surfactant Concentrations: Optimization of Structure and Properties by Glycol Cosurfactants
    • Patrycja Szumała
    • Szymon Mania
    • Balbina Makurat-Kasprolewicz
    • Jolanta Kaplińska
    2023 Pełny tekst MOLECULAR PHARMACEUTICS

    Extensive use of microemulsions as delivery systems raises interest in the safe ingredients that can form such systems. Here, we assessed the use of two glycols, i.e., propylene glycol and pentylene glycol, and their mixtures to manipulate the properties and structure of microemulsions. Obtained systems with glycols were extensively characterized in terms of capacity to incorporate water phase, droplet size, polydispersity, structure type, and rheological and thermal properties. The results of these studies indicate that the composition, structure, and viscosity of the microemulsions can be changed by appropriate quantification of glycols. It has been shown that the type of glycol used and its amount may favor or worsen the formation of microemulsions with the selected oils. In addition, a properly selected composition of oils and glycols resulted in the formation of microemulsions with a reduced content of surfactants and consequently improved the safety of using microemulsions as delivery systems.

  • Microfluidic SIW-Based Tunable Self-Diplexing Antenna for Sub-6 GHz Band Applications
    • Nrusingha Pradhan
    • Goutham Reddy
    • Karthikeyan Subramanian
    • Rusan Kumar Barik
    • Sławomir Kozieł
    • Qingsha Cheng
    2023 IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS

    This work introduces a novel frequency tunable self-diplexing antenna (SDA) design based on substrate integrated waveguide (SIW) technology. A modified A-shaped slot is employed on the cavity’s top plane, which is excited by two independent 50 Ω microstrip feed lines to operate at each resonant frequency. The frequency flexibility of the proposed antenna allows for fine-tuning at each resonance frequency. The frequency flexibility has been achieved by employing the substrate’s air- and liquid-filled pockets. The proposed antenna can be configured to operate in the 3.5-3.8 GHz and 5.53-6.2 GHz bands, as demonstrated by the simulation results. With distilled water-filled pockets, the proposed antenna offers peak gains of 5.04 dBi and 5.26 dBi. The proposed SDA exhibits competitive features such as a highly compact size of 0.22λg2 and high isolation (>27dB), which makes it suitable for handheld communication devices. The simulated and measured circuit responses are in good agreement.

  • Microplastics removal from aqueous environment by metal organic frameworks
    • Zhila Honarmandrad
    • Massoud Kaykhaii
    • Jacek Gębicki
    2023 Pełny tekst BMC Chemistry

    This paper provides an overview of recent research performed on the applications of metal–organic frameworks (MOFs) for microplastics (MPs) removal from aqueous environments. MPs pollution has become a major environmental concern due to its negative impacts on aquatic ecosystems and human health. Therefore, developing effective and sustainable methods for removing them from aqueous environments is crucial. In recent years, MOFs have emerged as a promising solution for this purpose due to their unique properties such as high surface area, renewability, chemical stability, and versatility. Moreover, their specific properties such as their pore size and chemical composition can be tailored to enhance their efficiency in removing MPs. It has been shown that MOFs can effectively adsorb MPs from aqueous media in the range of 70–99.9%. Besides some high price concerns, the main drawback of using MOFs is their powder form which can pose challenges due to their instability. This can be addressed by supporting MOFs on other substrates such as aerogels or foams. Meanwhile, there is a need for more research to investigate the long-term stability of MOFs in aqueous environments and developing efficient regeneration methods for their repeated use.

  • Microscopic Imaging to Visualize the Distribution of Dietary Nucleic Acids in Food Products of Various Origins
    • Anna Kościelak
    • Zuzanna Koziara
    • Ana Pons Maria
    • Rafał Płatek
    • Agnieszka Bartoszek-Pączkowska
    2023 Pełny tekst Foods

    Dietary nucleic acids (dietNAs) are being increasingly recognized as important food components with nutritional value. However, the precise dietary recommendations for dietNAs are limited, because established methods for determining the quantity and nutritional role of dietNAs are still lacking. One of the tools to narrow this gap could be microscopic imaging, as a convenient approach to visualize the abundance and distribution of dietNAs in food products. With the aid of appropriate bioinformatic elaboration, such images may in future enable the direct semiquantitative estimation of these macromolecules in food products. In the presented study, two methods of preparing microscopic sections and staining them with DNA-specific fluorochromes were used for microscopic imaging of dietNAs in food products of plant and animal origin. Procedures for preparing formalin-fixed paraffin-embedded sections and cryosections were compared in terms of their usefulness for routine food analysis. Both methods turned out equally suitable for visualizing dietNA distribution in animal and plant products. However, the use of cryosections allowed a significantly shorter analysis time and reduced the consumption of organic solvents. Both of these advantages make the cryosection method preferable while establishing a dedicated methodology for routine assessment of dietNAs in the food industry.

  • Microstructure and Mechanical Properties of Combined GTAW and SMAW Dissimilar Welded Joints between Inconel 718 and 304L Austenitic Stainless Steel
    • Sachin Sirohi
    • Shailesh M. Pandey
    • Aleksandra Świerczyńska
    • Grzegorz Rogalski
    • Naveen Kumar
    • Michał Landowski
    • Dariusz Fydrych
    • Chandan Pandey
    2023 Pełny tekst Metals

    A dissimilar welded joint of Inconel 718 and 304L austenitic stainless steel was prepared using a combined procedure with the gas tungsten arc welding and shielded metal arc welding processes by employing the Ni-based fillers: ERNiCr-3 and ENiCrFe-3. The welded joints were investigated for metallographic testing and mechanical properties, and a relationship was established between the microstructure and the resultant mechanical properties. Microstructural observation revealed the formation of the unmixed zone on the 304L SS side. The weld metal showed that the fully austenitic microstructure consisted of the Nb- and Ti-rich carbide phases along the inter-dendritic spaces. The tensile test results at room temperature showed the failure from the weld metal which might be due to alloying element segregation along the inter-dendritic spaces. However, a tensile test at 600 ◦C showed the failure from the 304L SS base metal with a tensile strength and % elongation value of 377 MPa and 24%, respectively. The hardness plot showed the average hardness value of the weld metal of 236 ± 5 HV, which was higher than the 304L SS BM (204 ± 4 HV) but lower than the IN718 BM (243 ± 5 HV). The impact toughness of the weld metal was 109 J, which was significantly lower than the base metals. The poor impact strength of the weld metal might be due to the evolution of the NbC phase along inter-dendritic spaces

  • Mind the framing: Match purpose and context
    • Monica Fiore, Di
    • Marta Kuc-Czarnecka
    • Samuele Lo Piano
    • Arnald Puy,
    • Andrea Saltelli,
    2023

    In several ways, the following chapters will allude to the concept of frames. The assumptions of a mathematical model tell us what it can explain and what it cannot (see chapter 5). The trade-off between the usefulness of a mathemati- cal model and the scale of complexity it seeks to capture further conditions the narrative, highlighting or downsizing cognitive elements relevant to responsible modelling (see ‘Mathematics and tales’ in chapter 4). Yet, what determines the choice of a model, its assumptions, and its level of complexity? Answering these questions requires a more general perspective that involves frames—that is, the complex of cognitive schemes through which we reason and which we use to make sense of the world. The notion of the frame owes much to the tradition of social studies. Several disciplines have underlined the importance of worldviews and their causal rela- tionships in giving us the coordinates to classify the situations in which we find ourselves. Since public policies are constructs of considerable complexity, policy inquiry has paid great attention to the frames we use to organize information, ideas, and beliefs. For example, Campbell (2002), analysing the effects of ideas, worldviews, and cognitive paradigms on policy-making, defines frames as ‘nor- mative and sometimes cognitive ideas that are located in the foreground of policy debates’.

  • Miniatura, mały format, duże możliwości
    • Joanna Golińska-Pilarek
    • Renata Mazurkiewicz
    • Anna Strzebońska
    • Joanna Wolszczak-Derlacz
    2023 Pełny tekst Forum Akademickie

    MINIATURA to program Narodowego Centrum Nauki przeznaczony do realizacji pojedynczego działania naukowego z zakresu badań podstawowych. Zrównoważona dystrybucja środków w MINIATURZE, zarówno pod względem typów jednostek naukowych, jak i województw, pokazuje, że MINIATURA jest ważną formą wsparcia finansowego w ofercie grantowej NCN, która dobrze odpowiada na zapotrzebowanie mniejszych ośrodków na tzw małe granty

  • Miniaturized Dual-Band SIW-Based Bandpass Filters Using Open-Loop Ring Resonators
    • Nrusingha Pradhan
    • Sławomir Kozieł
    • Rusan Kumar Barik
    • Anna Pietrenko-Dąbrowska
    • Karthikeyan Subramanian
    2023 Pełny tekst Electronics

    This article presents two novel architectures of dual-band substrate integrated waveguide (SIW) bandpass filters (BPFs). Initially, two identical open-loop ring resonators (OLRRs) are coupled face-to-face on the top of the SIW cavity to realize a dual-band single-pole BPF. To obtain two-pole dual-band characteristics, two OLRRs resonant units are assembled horizontally within the top metal layer of the SIW, which is a technique used for the first time in the literature. For demonstration purposes, two types of SIW filters loaded with OLRRs are designed and fabricated. The proposed filters feature an extremely compact size, a low insertion loss, and good selectivity. The single- and two-pole filters have an overall size of 0.012λg2 and 0.041λg2, respectively. The simulated and measured circuit responses are in good agreement.