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  • Stability Investigation of the PCM Nanocomposites
    • Janusz Cieśliński
    • Paulina Boroń
    • Maciej Fabrykiewicz
    2023 Pełny tekst Acta Mechanica et Automatica

    Ensuring the stability is a key issue to be solved for the technical application of nanocomposites. In this work, fatty acid P1801 served as base phase change material (PCM)P1801, and its main ingredients are palmitic acid (58%) and stearic acid (38%). Titania (TiO2) and alumina (Al2O3) with mass concentrations of 1% and 5% were selected as nanoparticles, while polyvinylpyrrolidone (PVP) or oleic acid (OA) with mass concentrations of 5% were tested as surfactants. On the basis of the measured temperature distributions in the sample, which is subject to melting and solidification processes, it was determined which of the tested nanocomposites are stable and which are not. In addition, a thermal test was proposed to assess the stability of the produced nanoPCM, which consists in measuring the temperature distribution versus time according to a precisely given procedure.

  • State Interventionism in Tax System - Example of Action in a COVID-19 Crisis
    • Piotr Kasprzak
    2023 Pełny tekst International Journal of Social Science

    The following article presents and classifies changes in tax systems of selected countries as well as counts them as the response to the emergence of the crisis caused by the COVID-19 pandemic. Such actions were undertaken the context of state interventionism in the tax system. In order to achieve the objective of presenting the state interventionism in the context of tax rates, an analysis of the literature on the phenomenon described, as well as specialised industry reports, were analysed. Among the research methods used are literature studies as well as review and an analysis of reports published by the OECD that dealt with the subject described and analysed in the paper. The article focuses on the presentation of the change in the individual tax burden in the countries selected for analysis. It also focuses on the presentation of tax interventionism as an opportunity for the state to influence the economy against the negative effects of the crisis. It should be noted that crises and crisis situations play an crucial role in the economic life of a country, but their course and ultimate consequences depend on the measures taken by individual countries to reduce the negative effects of their outbreak. The COVID-19 pandemic had a significant impact on changing the macroeconomic perspective and situation of many countries around the globe. The pandemic outbreak had also a negative impact on the functioning of companies (especially SME sector). As a result, governments have decided to introduce various relief measures, including changes in the functioning of tax systems. This should be considered as the state interventionism.

  • Static in vitro digestion model adapted to the general older adult population: an INFOGEST international consensus
    • O Ménard
    • U Lesmes
    • C. S. Shani-Levi
    • A. Araiza Calahorra
    • A. Lavoisier
    • M. Morzel
    • A. Rieder
    • G. Feron
    • S. Nebbia
    • L. Mashiah
    • Ana Andres
    • G. Bornhorst
    • F Carriere
    • L Egger
    • S. Gwala
    • Ana Heredia
    • B Kirkhus
    • Adam Macierzanka
    • R Portmann
    • I Recio
    • V. Santé-Lhoutellier
    • C. Tournier
    • A. Sarkar
    • A Brodkorb
    • Alan Mackie
    • D Dupont
    2023 Pełny tekst Food & Function

    Understanding the mechanisms of food digestion is of paramount importance to determine the effect foods have on human health. Significant knowledge on the fate of food during digestion has been generated in healthy adults due to the development of physiologically-relevant in vitro digestion models. However, it appears that the performance of the oro-gastrointestinal tract is affected by ageing and that a model simulating the digestive conditions found in a younger adult (<65 years) is not relevant for an older adult (>65 years). The objectives of the present paper were: (1) to conduct an exhaustive literature search to find data on the physiological parameters of the older adult oro-gastrointestinal tract, (2) to define the parameters of an in vitro digestion model adapted to the older adult. International experts have discussed all the parameters during a dedicated workshop organized within the INFOGEST network. Data on food bolus properties collected in the older adult were gathered, including food particle size found in older adult boluses. In the stomach and small intestine, data suggest that significant physiological changes are observed between younger and older adults. In the latter, the rate of gastric emptying is slowed down, the pH of the stomach content is higher, the amount of secretions and thus the hydrolytic activities of gastric and intestinal digestive enzymes are reduced and the concentration of bile salts lower. The consensus in vitro digestion model of the older adult proposed here will allow significant progress to be made in understanding the fate of food in this specific population, facilitating the development of foods adapted to their nutritional needs. Nevertheless, better foundational data when available and further refinement of the parameters will be needed to implement the proposed model in the future.

  • Static Shape and Stress Control of Trusses with Optimum Time, Actuators and Actuation
    • Najmadeen Saeed
    • Ahmed Manguri
    • Marcin Szczepański
    • Robert Jankowski
    • Barham. A. Haydar
    2023 Pełny tekst International Journal of Civil Engineering

    Traditional shape and stress control of structures use many actuators and require enormous time to find reasonable solutions that need designers to input specific target displacement and stress. This study employs a linear technique to static shape and stress control of pin-jointed assemblies as a theoretical advancement to prior works and provides a comparative analysis against previously established works. The study evaluates the proposed method using MATLAB to find the optimum set of actuators, and MATLAB and SAP2000 to verify the actuation results obtained through applying the set of actuations to the numericalmodels. The proposed method minimizes the number of trials, count of actuators, and total actuation up to 83%, 73%, and 50%, respectively. Furthermore, the optimum solution could be found in a single trial. The study focuses on the three aspects: (a) finding the optimal count of actuators; (b) optimum amount of actuation using fmincon function; and c) Implementing two-sided inequalities to control equations allowing designers to develop target internal forces and nodal displacements, as domains rather than specific numbers. This improves the optimization process affecting actuator count, total actuation elements, and processing time.

  • Statistical evaluation of the changes in cellulose properties caused by the stepwise solvent exchange and esterification
    • Stefan Cichosz
    • Katarzyna Dems-Rudnicka
    • Marcin Łapiński
    • Aleksandra Jastrzębska
    • Anna Masek
    2023 INDUSTRIAL CROPS AND PRODUCTS

    The objective of the research was to empirically confirm the changes in cellulose reactivity caused by the pre-treatment with solvents of different polarity. Therefore, 5 solvents varying in their polar component of surface tension from 0 to 4.6 mN/m were chosen. Their impact on the biopolymer properties was carefully analysed concerning chemical structure, crystallinity and surface characteristics. It was revealed that the length of 6OH⋯O3′ intermolecular H-bonds increased upon each solvent-exchange from (0.2748 ± 0.0001) nm to approx. 0.2760 nm for non-polar solvents, hence, potentially affecting cellulose structure and availability of active centres capable of reaction. As a consequence of structural variations, dioxane- and toluene-exchanged cellulose exhibited, respectively, the lowest (around 0.6 mJ/m2) and the highest (approx. 3.1 mJ/m2) polar component of surface free energy. Therefore, these samples were esterified. Further investigation successfully confirmed expected differences. Toluene-exchanged sample exhibited degree of substitution oscillating around 20%, while dioxane-exchanged specimen – approx. 7%.

  • Steady-State Vibration Level Measurement of the Five-Phase Induction Machine during Third Harmonic Injection or Open-Phase Faults
    • Adam Muc
    • Marcin Morawiec
    • Filip Wilczyński
    2023 ENERGIES

    Multiphase electric machines are increasingly used in various industries and for electromobility. Complex systems have been developed for the control and powering of multiphase machines, which require verification. The quality of control and the power supply of electric machines is usually evaluated by analyzing various electrical parameters. On the other hand, taking into account the fact that a motor is an electrical-mechanical object, its full diagnostics should also include the analysis of vibration signals to verify the operation of the motor as a mechanical device. In this paper, a sensorless control algorithm was studied and applied to a 5-phase induction motor. Various scenarios were considered; in particular, the operation of the studied motor in the absence of one or two phases and in the case of the introduction of the third harmonic to increase the torque was analyzed. In the scenarios considered, the motor was connected to another machine and operated with no load as well as with a preset load. The results obtained were analyzed in the time and frequency domain and were related to the standards used.

  • Stenty naczyniowe – problematyka i biomateriały
    • Klaudia Malisz
    • Marcin Hellmann
    • Beata Świeczko-Żurek
    2023

    Angioplastyka z opcjonalną implantacją stentu odgrywa ważną rolę w leczeniu chorób układu sercowo-naczyniowego w przebiegu miażdżycy. Obecnie na rynku można znaleźć implanty naczyniowe z różnych materiałów, pomimo tego nadal prowadzone są badania nad nowymi technologiami zapewniającymi lepsze własności mechaniczne, fizykochemiczne i biologiczne powłokom, a także usprawniającymi sposoby uwalniania leków. Stenty uwalniające leki dostarczają środki antyproliferacyjne, co znacznie obniża częstość nawrotów zwężenia w porównaniu ze stentami z czystego metalu. Chociaż w pełni biodegradowalne rusztowania potencjalnie mają zapobiegać późnym powikłaniom, nie osiągnęły jeszcze wyników równoważnych z wynikami konwencjonalnych metalowych stentów uwalniających leki we wczesnych latach po implantacji. Innym rozwiązaniem jest zastosowanie powłok, które nadają wyjątkowych właściwości materiałowi, np. wykorzystując powłoki diamentopodobne lub domieszkując powłokę nanocząstkami. Celem niniejszego artykułu jest przedstawienie najnowszych materiałów do stosowania w kardiologii i angiologii interwencyjnej jako stenty naczyniowe.

  • Sterowanie predykcyjne i fuzja danych w systemie dynamicznego pozycjonowania statku
    • Krzysztof Jaroś
    2023 Pełny tekst

    Rozprawa doktorska poświęcona jest badaniu zastosowania fuzji danych oraz sterowania predykcyjnego w systemie dynamicznego pozycjonowania statku. W pierwszej części pracy przedstawiono historię rozwoju systemów dynamicznego pozycjonowania, różne metody estymacji położenia statku, metody sterowania oraz cel i tezę pracy. Następnie zaprezentowano model matematyczny statku, kinematykę oraz dynamikę. W kolejnej części przedstawiono algorytmy fuzji danych, takie jak filtr Kalmana, rozszerzony filtr Kalmana, nieliniowy obserwator oraz filtr cząsteczkowy. W rozprawie przedstawiono również algorytm kaskadowego połączenia filtru cząsteczkowego i rozszerzonego filtru Kalmana. W kolejnej części zaprezentowano algorytmy sterowania, takie jak PID, regulator backstepping oraz sterowanie predykcyjne. W pracy przedstawiono dwa kierunki badań. Pierwszy dotyczy zadania fuzji danych z wykorzystaniem nadmiarowej struktury pomiarowej dokonującej pomiaru położenia, kursu i prędkości w celu estymacji tych wielkości i zakłóceń środowiskowych. Drugi kierunek badań dotyczy poprawy jakości sterowania statkiem z wykorzystaniem nieliniowego modelu statku w sterowaniu predykcyjnym. Wyniki tych badań wskazują, że połączenie fuzji danych i sterowania predykcyjnego pozwala na zwiększenie dokładności pozycjonowania statku oraz bezpieczeństwa statku w sytuacjach awaryjnych.

  • Stiffness of cold-recycled mixtures under variable deformation conditions in the IT-CY test
    • Mariusz Jaczewski
    • Cezary Szydłowski
    • Bohdan Dołżycki
    2023 Pełny tekst Case Studies in Construction Materials

    Stiffness modulus belongs to the most important properties describing the cold-recycled mixtures (CRM) in terms of their usability in road pavement structures. Previous research proved that this property is strongly dependent on the scheme and conditions of the test (temperature and time of loading) and the time that has passed since the compaction of the specimen or pavement layer. It is a result of the influence of two different types of bonds – hydraulic bonds from cement and bituminous bonds from bituminous emulsion or foamed bitumen. Research presented in this paper showed that the target horizontal deformation values selected during the stiffness modulus test have a strong impact on the obtained results as well. In this paper the popular Indirect Tensile Stiffness Modulus (ITSM) test on cylindrical specimen (IT-CY scheme) was used to show the dependence of the stiffness modulus values on the selected target horizontal deformation level. Research was conducted on four different CRM mixtures and three reference materials. The research proved that even for a narrow deformation range the CRMs do not present linear viscoelastic behavior and display very high effort of material even for typical test conditions. In consequence, they are very prone to failure. Research also proved that CRM mixtures present different rheological behavior than cement concrete or asphalt concrete, and more attention should be given to establishing proper test conditions. Based on the research, it was determined that the recommended target horizontal deformation in IT-CY test of CRM should be reduced to 3 μm.

  • Stochastic optimisation algorithm for optimisation of controller parameters for control of dissolved oxygen in wastewater treatment plant
    • Robert Piotrowski
    • Michał Wonia
    • Adam Wonia
    2023 Journal of Water Process Engineering

    Wastewater treatment plants (WWTPs) are very important facilities for mankind. They enable the removal and neutralisation of man-made pollutants. Therefore, it is important for wastewater treatment plants to operate as efficiently as possible so that the level of pollutants in the treated wastewater meets specific requirements. This paper concerns the design of a hierarchical nonlinear adaptive control system for dissolved oxygen (DO) concentration in wastewater for a biological Sequential Batch Reactor (SBR). The parameters of the control system used are optimised to ensure the best possible control quality and low energy consumption at the same time. Based on data collected from a case study WWTP, an Activated Sludge Model 2d (ASM2d) of the biological processes and a model of the aeration system are applied. The Coyote Optimization Algorithm (COA) is used to optimize the adaptive controller parameters. A Proportional-Integral-Derivative (PID) control system is also developed to compare the control results. The results obtained from simulation studies for both control systems are presented. As a result of optimised parameters, higher wastewater treatment efficiency and reduced electricity consumption are achieved.

  • Stock Markets’ Reactions to the Announcement of the Hosts. An Event Study in the Analysis of Large Sporting Events in the Years 1976–2032
    • Krystian Zawadzki
    • Marcin Potrykus
    2023 Pełny tekst Journal of Sports Economics

    This study attempts to estimate the impact of the announcements of hosts of large sporting events on domestic stock markets. The research problem is to establish a connection between the uniqueness of a sporting event and investors’ beliefs through stock price behavior. Using appropriate estimation windows, 13 different sporting events classified as large, including mega and major events, were tested. The obtained results show that, in principle, one day after the announcement of the host of a large sporting event, an average positive reaction of 0.22% is observed on national stock exchanges. The analyzed events were also classified as being neutral for capital markets or generating positive or negative reactions when the host country is announced to the public.

  • Strategies for Dealing With Software Product Management Challenges
    • Olga Springer
    • Jakub Miler
    • Michał Wróbel
    2023 Pełny tekst IEEE Access

    Software product management, which involves multiple processes and responsibilities and links to many activities within the organisation, increases the success rate of IT projects. However, the adoption of product management activities and the implementation of the software product manager role itself varies between companies. This research explores the topic of software product managers’ strategies for dealing with challenges in their work. The aim of the study is to identify and evaluate solutions to the main problems that affect the software product management process and to provide guidelines for dealing with them. For this purpose, a focus group method was adopted and 47 software product managers participated in 15 focus groups. This was followed by a survey to assess the comprehensibility and effectiveness of the solutions identified. The paper proposes a list of 39 solutions to the 5 most common problems in the work of product managers. Furthermore, based on the identified solutions and the results of discussions with experienced professionals during the focus groups, guidelines for these problems were also developed. These guidelines can be used by product managers as well as other roles working in the product development team to create their own strategies for overcoming software product management challenges and improving software engineering practices. Finally, the solutions and guidelines presented, when combined with a list of problems identified in previous research, will form a Software Product Management Guide – a framework currently under construction, as part of wider research, for product development teams to improve software engineering practices.

  • Strategy towards the use of ultrafiltration and reverse osmosis for industrial water recovery and reuse as part of the Green Deal Implementation
    • Jakub Drewnowski
    • Jan Marjanowski
    • Maciej Sadaj
    • Bartosz Szeląg
    • Joanna Szulżyk-Cieplak
    • Grzegorz Łagód
    2023 Desalination and Water Treatment

    In line with the European Parliament’s Resolution of February 10th, 2021 on the new action plan for a closed economy, most of the activities undertaken in the wastewater treatment process should focus on the search for new technologies that use wastewater as a source of water and nutrients. The paper reviews the concept of water reuse in industrial installations, with special emphasis on the use of membrane technologies for this purpose. The results of authors’ own research on effectiveness of using ultrafiltration (UF) and reverse osmosis (RO) processes to recover process water from brewery wastewater, following pretreatment by the BIOPAQ®-IC process, are presented. Raw wastewater, after averaging the parameters, was digested in an anaerobic reactor, followed by deodorization and oxidation of sulfides to sulfate in an oxidation process in a pretreatment tank. The water recovered from pretreated brewery wastewater by UF and RO membrane techniques was found to be suitable for boiler feed, cooling technology and washing process without directly cleaning beer bottles. The study used a ZeeWeed capillary immersion ultrafiltration module operating under vacuum and a module equipped with a Filmtec XLE 2125 reverse osmosis membrane. The technology improved the efficiency of contaminant removal, yielding purified and high-quality water toward the implementation of the assumptions of Circular Economy and Green Deal Implementation.

  • Stress Relaxation Behaviour Modeling in Rigid Polyurethane (PU) Elastomeric Materials
    • Paweł Zielonka
    • Krzysztof Junik
    • Szymon Duda
    • Tomasz Socha
    • Krzysztof Kula
    • Arkadiusz Denisiewicz
    • Olaleye Kayode
    • Wojciech Macek
    • Grzegorz Lesiuk
    • Wojciech Błażejewski
    2023 Pełny tekst Materials

    Polyurethane (PU) has been used in a variety of industries during the past few years due to its exceptional qualities, including strong mechanical strength, good abrasion resistance, toughness, low-temperature flexibility, etc. More specifically, PU is easily “tailored” to satisfy particular requirements. There is a lot of potential for its use in broader applications due to this structure–property link. Ordinary polyurethane items cannot satisfy people’s increased demands for comfort, quality, and novelty as living standards rise. The development of functional polyurethane has recently received tremendous commercial and academic attention as a result. In this study, the rheological behavior of a polyurethane elastomer of the PUR (rigid polyurethane) type was examined. The study’s specific goal was to examine stress relaxation for various bands of specified strains. We also suggested the use of a modified Kelvin–Voigt model to describe the stress relaxation process from the perspective of the author. For the purpose of verification, materials with two different Shore hardness ratings—80 and 90 ShA, respectively—were chosen. The outcomes made it possible to positively validate the suggested description in a variety of deformations ranging from 50% to 100%.

  • Structural and electronic properties of diamond-composed heterostructures
    • Michał Rycewicz
    2023 Pełny tekst

    Diamond is a promising material for 21st century electronics due to its high thermal and electronic conductivity, biocompatibility, chemical stability, high wear resistance, and possibility of doping. However, the semiconductor properties of diamond, especially free-standing films, have not been fully explored. Nor have their integration with polymers and fragile materials and their applications as electronic components. In this thesis, the objective was the fabrication of heterostructures containing diamond films on flexible surfaces for application in electronic devices using the change of electrical parameters under the influence of external factors. To overcome this scientific challenge, boron-doped diamonds were grown using chemical vapour deposition on tantalum. After their delamination, the resulting free-standing films were investigated and analysed using Raman spectroscopy, Scanning and Atomic Force Microscopy, Nanoindentation Tests, Electrochemical measurements, and Electrical Evaluation as a function of temperature. Next, the diamond films were utilised for fabricating six heterostructures. Based on the conducted research, these heterostructures can be used as durable, transparent electrodes, strain sensors, Schottky or Ohmic junctions, capacitors, trinitrotoluene sensors, and as a protective layer for transistors.

  • Structural and luminescence properties of B2O3-Bi2O3-AlF3 glass doped with Eu3+, Tb3+ and Tm3+ ions
    • Karolina Milewska
    • Michał Maciejewski
    • Marcin Łapiński
    • Anna Synak
    • Mirosław Behrendt
    • Wojciech Sadowski
    • Barbara Kościelska
    2023 JOURNAL OF NON-CRYSTALLINE SOLIDS

    The B2O3-Bi2O3-AlF3 glass system doped with Eu3+, Tb3+, Tm3+ and triply doped with Eu3+/Tm3+/Tb3+ ions in different molar ratios were successfully synthesized. Glass transition and crystallization temperatures were examined by Differential Scanning Calorimetry (DSC) measurements. X-ray Diffraction (XRD) confirmed the amorphous character of the samples. Fourier Transform Infrared Spectroscopy (FTIR) revealed that the glass matrix consists of [BO3] and [BO4] structural units, while X-ray Photoelectron Spectroscopy (XPS) confirmed the presence of AlF3. An increase in luminescence spectra intensity was detected by Photoluminescence Spectroscopy (Pl), due to the presence of 10 mol% of AlF3. The RE3+ ions embedded in the glass matrix can be simultaneously excited by a single UV light. According to the CIE results the emitted color can be tunable by varying the excitation wavelength and sample composition. The presented results confirm that the proposed glass system could be a candidate for color-tunable phosphors in LEDs.

  • Structural insights, biocatalytic characteristics, and application prospects of lignin-modifying enzymes for sustainable biotechnology
    • Anil Kumar Singh
    • Hafiz M N Iqbal
    • Nunzio Cardullo
    • Vera Muccilli
    • Jesús Fernández-Lucas
    • Jens Ejbye Schmidt
    • Teofil Jesionowski
    • Muhammad Bilal
    2023 Pełny tekst INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES

    Lignin modifying enzymes (LMEs) have gained widespread recognition in depolymerization of lignin polymers by oxidative cleavage. LMEs are a robust class of biocatalysts that include lignin peroxidase (LiP), manganese peroxidase (MnP), versatile peroxidase (VP), laccase (LAC), and dye-decolorizing peroxidase (DyP). Members of the LMEs family act on phenolic, non-phenolic substrates and have been widely researched for valorization of lignin, oxidative cleavage of xenobiotics and phenolics. LMEs implementation in the biotechnological and industrial sectors has sparked significant attention, although its potential future applications remain underexploited. To understand the mechanism of LMEs in sustainable pollution mitigation, several studies have been undertaken to assess the feasibility of LMEs in correlating to diverse pollutants for binding and intermolecular interactions at the molecular level. However, further investigation is required to fully comprehend the underlying mechanism. In this review we presented the key structural and functional features of LMEs, including the computational aspects, as well as the advanced applications in biotechnology and industrial research. Furthermore, concluding remarks and a look ahead, the use of LMEs coupled with computational framework, built upon artificial intelligence (AI) and machine learning (ML), has been emphasized as a recent milestone in environmental research.

  • Structural, optical and electrochemical performance of black phosphorus and black arsenic-phosphorus nanostructures
    • Łukasz Macewicz
    2023 Pełny tekst

    Black phosphorus (BP)-based nanostructures have drawn a lot of attention due to their tunable bandgap and extraordinary properties such as: high surface-to-volume ratio, large number of active sites, and prominent edges. However, low dimensional structures of black phosphorus oxidize easily, which hamper their application on a broader scale. One way to overcome these difficulties is to modify the black phosphorus structure by substituting some of the phosphorus atoms for arsenic atoms, forming black arsenic-phosphorus (b-AsP). Despite the broad variety of atomically thin, two-dimensional materials, those with a bandgap range between 0.3 and 1.5 eV are plainly missing. Black phosphorus and black arsenic-phosphorus nanostructures not only correspond to the visible and infrared spectral range, but also possess additional tuning capabilities, which can further influence their electronic properties. In this dissertation, the structural and optical properties of BP and b-AsP nanoflakes and nanoribbons have been investigated. Moreover, surface modification of electrode materials with BP and b-AsP to enhance their electrochemical performance and sensing possibilities was investigated. The electrode materials chosen for BP and b-AsP modification were titania nanotubes (TiO2NTs), commercially available gold array electrodes, and CVD-fabricated polycrystalline boron-doped diamond (BDD) films.

  • Structural, physicochemical and anticancer study of Zn complexes with pyridyl-based thiazolyl-hydrazones
    • Jovana B. Araškov
    • Natalia Maciejewska
    • Mateusz Olszewski
    • Aleksandar Višnjevac
    • Vladimir Blagojević
    • Henrique S. Fernandes
    • Sérgio F. Sousa
    • Adrián Puerta
    • José M. Padrón
    • Berta Barta Holló
    • Miguel Monge
    • María Rodríguez-castillo
    • José M. López-de-luzuriaga
    • Özlem Uğuz
    • Atıf Koca
    • Tamara R. Todorović
    • Nenad R. Filipovići
    2023 JOURNAL OF MOLECULAR STRUCTURE

    Thiazolyl-hydrazones (THs) exhibit a wide spectrum of biological activity that can be enhanced by complexation with various metal ions. Zn(II) complexes with α-pyridine-1,3-TH ligands may represent an alternative to the standard platinum-based chemotherapeutics. In addition, they show photoluminescence properties and thus can be regarded as multifunctional materials. In this study, we synthesized and characterized three neutral Zn(II) complexes (1–3) with pyridine-based TH ligands HLS1‒3 in order to investigate the influence of the ligands charge on the structure and intermolecular interactions in the solid state, and consequently photophysical properties. The deprotonation of the ligands mainly affects the relative energies of electronic levels in the complexes, compared to cationic counterparts, resulting in similar photoluminescence mechanisms and quantum yields with a small shift in emission energy. The influence of the substitution at the ligands’ periphery on the selected quantum molecular descriptors of the complexes is localized to the substitution site. Also, the substituents did not considerably influence the redox responses of the complexes. However, predominant spectral changes were observed in the course of the first reduction and oxidation processes which caused distinct spectral colour changes indicating their possible functionality for electrochromic applications. In addition, complex 1 showed antiproliferative activity with GI50 values below 2 µM on all tested cancer cell lines.

  • Structurally well-defined functionalized polyolefins and graft copolymers thereof as bitumen modifiers
    • Mateusz Malus
    • Joanna Bojda
    • Maciej Sienkiewicz
    • Miloud Bouyahyi
    • Lanti Yang
    • Javier Francisco Navarro
    • Maria Soliman
    • Rob Duchateau
    • Lidia Jasińska-Walc
    2023 CONSTRUCTION AND BUILDING MATERIALS

    Here we demonstrate the application of hydroxyl-functionalized propylene-based copolymers, poly(propylene-co-1-hexene-co-10-undecen-1-ol) (FPP) and poly(styrene-co-maleic anhydride) (SMA) graft copolymers derived thereof, poly(propylene-co-1- hexene-graft-styrene-co-maleic anhydride) (FPP-g-SMA) as bitumen modifiers. The FPP samples were synthesized via solution copolymerization, while FPP-g-SMA products were obtained via transesterification of FPP with SMA either in solution or by a melt-grafting process. FPP-g-SMA modifiers prepared in solution, having a SMA content of around 30 wt.%, performed very well as compatibilizer for bitumen, generating a polymer-modified compositions with a uniform morphology and improved nanomechanical properties, storage stability, rheological properties and high- temperature performance as compared to neat bitumen samples.