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  • Sustainable polymers targeted at the surgical and otolaryngological applications: Circularity and future
    • Przemysław Gnatowski
    • Justyna Kucińska-Lipka
    2023 Pełny tekst Polymers from Renewable Resources

    The ongoing climate changes, high air and noise pollution have significant impact on humans’ health. This influence is especially visible in otolaryngology, which focuses on respiratory and hearing systems disfunctions. However, even though surgeries are done in response to diseases related to climate changes, they also have a negative impact on the environment, mostly connected with the inherence of single-use fossil fuel derived polymers. This leads to a self-perpetuating emission of greenhouse gases, as human beings developed a lot of synthetic materials to combat climate change derived dysfunctions, which itself endangers human health in a chaotic circular chain. Mitigating issues arising from using synthetic plastics would be possible by imparting biodegradable polymers from renewable resources. Nowadays, sustainable polymers are adopted mostly in emerging fields of medicine, such as 3D printing, tissue engineering of drug delivery systems. Sustainable polymers are particularly useful in otolaryngology, e.g., in the form of nasal drug eluting stents or bone substitutions. Nevertheless, some limitations in wider usage of renewable polymers in surgery should also be underlined, mainly related to lack of legislation, clinical considerations, and also inadequate materials’ circularity. Herein we briefly overviewed commonly used polymers in general surgery and otolaryngology, defined the trends in sustainable polymer usage in these fields, and highlighted the limitations in renewable polymers applications together with possible solutions. What this short review emphasizes, is that the significant increase in interest and demand for sustainable solutions will revolutionize the future of clinical treatments, where contribution to climate change and waste management will be centered in decision making protocols.

  • Sustainable Strategy for Algae Biomass Waste Management via Development of Novel Bio-Based Thermoplastic Polyurethane Elastomers Composites
    • Ewa Głowińska
    • Olga Gotkiewicz
    • Paulina Kosmela
    2023 Pełny tekst MOLECULES

    This work concerns the waste management method of algae biomass wastes (ABW). For this purpose, we prepared bio-based thermoplastic polyurethane elastomer (bio-TPU) composites. Algae biomass wastes are derived from algal oil extraction of Chlorella vulgaris and from biomass of Enteromorpha and Zostera marina. ABWs were used in the bio-TPUs composites as a filler in the quantity of 1, 5, 10, and 15 wt.%. The bio-based composites were prepared via the in situ method. Polymer matrix was synthesized from a bio-based polyester polyol, diisocyanate mixture (composed of partially bio-based and synthetic diisocyanates), and bio-based 1,3 propanediol. In this study, the chemical structure, morphology, thermal and mechanical properties of prepared composites were investigated. Based on the conducted research, it was determined that the type and the content of algae waste influence the properties of the bio-based polyurethane matrix. In general, the addition of algae biomass wastes led to obtain materials characterized by good mechanical properties and noticeable positive ecological impact by increasing the total amount of green components in prepared bio-TPU-based composites from 68.7% to 73.54%.

  • Sustainable utilization of copper post-flotation waste in cement composites
    • Szymon Kalisz
    • Marek Lieder
    • Elżbieta Haustein
    • Aleksandra Kuryłowicz-Cudowska
    2023 CONSTRUCTION AND BUILDING MATERIALS

    The current way of managing the copper ore flotation waste is by placing it in waste neutralization facilities. However, flotation waste has great potential in application in cement composites. The article presents the detailed characteristics of post-flotation waste (PFW) and three types of cements: CEM I, CEM II/B-V, and CEM III/A, 42.5 MPa class. The post-flotation waste added for 20% of the cement mass increase the water demand to obtain the standard consistency. The highest pozzolanic activity was noted for mortars made of Ordinary Portland Cement and cured at 20 °C. The lower curing temperature, i.e. 10 °C, delays the hydration reaction, extends setting time, and reduces compressive strength. The conducted tests showed that the specimens produced from CEM I and PFW have the highest compressive strength (after 28 and 90 days), which means that PFW does not react with silica fly ash (from CEM II/B-V) and granulated blast furnace slag (from CEM III/A). The reaction of the waste with the components of the Portland clinker is preferred. The performed studies proved that the utilization of copper post-flotation waste allows for the development of sustainable and durable composite made of CEM I and indicated the possibilities of further testing of waste, in the direction of its use as a mineral additive for concrete.

  • Sustainable Waste Management for Implementation of a Circular Economy Model in a Port
    • Agnieszka Deja
    • Paweł Weichbroth
    • Wojciech Ślączka
    2023 Pełny tekst Procedia Computer Science

    The manuscript presents the management of waste from marine vessels and cargo handling companies in a selected European Union port. The main objective of the paper is to analyse and evaluate the existing waste management model in the port of Szczecin in the context of circular economy. The expert research carried out is aimed, inter alia, at identifying which of the solutions currently in use need to be improved from an environmental perspective. These measures could serve as a basis for the development of green logistics chains for waste generated in connection with the organisation of shipping. What is of particular importance in this regard is the information flow, which preferably should be an integral part of an international IT system enabling tracking of waste streams from their place origin to final disposal. In light of the above, it is particularly important to look for solutions which will support the creation and adoption of models providing sufficient control over the entirety of green waste management activities, in line with the circular economy concept.

  • Symbolic multibody models for digital-twin applications
    • Nicolas Docquier
    • Krzysztof Lipiński
    • Olivier Lantsoght
    • Sebastien Timmermans
    • Paul Fisette
    2023 MULTIBODY SYSTEM DYNAMICS

    Symbolic generation of multibody systems equations of motion appeared in the 1980s. In addition to their computational advantage over their numerical counterparts, symbolic models can be very easily and straightforwardly interfaced with a wide range of software environments and hardware devices. These two features place this approach in a pole position to participate and intervene in the design of digital twins for systems such as vehicles, manipulators, walking robots or haptic devices. In this context, the first goal of this paper is to highlight the interest of symbolically generated multibody models – at the root of the ROBOTRAN program – in the form of a standalone set of equations calculating the dynamic model of multibody systems, for use as a computational component within a Digital-Twin-type process. The next goal is to embed realistic and complex multibody models within processes or devices whose functioning requires a synchronized real-time computation – or analysis – of their motion. An implementation (i) on specific hardware and (ii) on two extremely opposite but revealing applications (namely a railway vehicle and a digital piano) are presented to highlight the usefulness of symbolic models for the development of current and future multibody-based digital twins.

  • Synchronization system for underwater acoustic communications using in shallow waters
    • Jan Schmidt
    • Aleksander Schmidt
    2023 Pełny tekst Vibrations in Physical Systems

    A reliable synchronization system of the transmitted data frame has a significant impact on the efficiency of the underwater communication system. This applies in particular to communication systems dedicated to work in shallow waters, where the phenomenon of multipath permanently occurs. To overcome these difficulties, the concept of a synchronization system consisting of two broadband signals of opposite monotonicity was presented. The method of receiving these signals has been described in detail. The stochastic channel model with Rician fading and the Watermark simulator was used to test the efficiency of the synchronization system in the underwater multipath channel.

  • Synchrotron radiation photoemission spectroscopy of the oxygen modified CrCl3 surface
    • S Kazim
    • D Mastrippolito
    • Paolo Moras
    • Matteo Jugovac
    • Tomasz Klimczuk
    • Mohamad Al Ali
    • Luca Ottaviano
    • Roberto Gunnella
    2023 Pełny tekst PHYSICAL CHEMISTRY CHEMICAL PHYSICS

    We investigate the experimentally challenging CrCl3 surface by photon energy dependent photoemission (PE). The core and valence electrons after cleavage of a single crystal, either in a ultrahigh vacuum (UHV) or in air, are studied by keeping the samples at 150 1C, aiming at confirming the atomic composition with respect to the expected bulk atomic structure. A common spectroscopic denominator revealed by data is the presence of a stable, but only partially ordered Cl–O–Cr surface. The electronic core levels (Cl 2p, Cr 2p and 3p), the latter ones of cumbersome component determination, allowed us to quantify the electron charge transfer to the Cr atom as a net result of this modification and the increased exchange interaction between metal and ligand atoms. In particular, the analysis of multiplet components by the CMT4XPS code evidenced the charge transfer to be favored, and similarly the reduced crystal field due to the established polarization field. Though it is often claimed that a significant amount of Cl and Cr atomic vacancies has to be included, such a possibility can be excluded on the basis of the sign and the importance of the shift in the binding energy of core level electrons. The present methodological approach can be of great impact to quantify the structure of ordered sub-oxide phases occurring in mono or bi-layer Cr trihalides.

  • Synergistic effects of nitrogen-doped carbon and praseodymium oxide in electrochemical water splitting
    • Patrycja Grabowska
    • Mariusz Szkoda
    • Malgorzata Skorupska
    • Jerzy P. Lukaszewicz
    • Anna Ilnicka
    2023 Pełny tekst Scientific Reports

    Hybrid materials featuring perovskite-type metal oxide in conjunction with heteroatom-doped graphene hold immense promise as alternatives to costly noble metal catalysts for electrochemical water splitting, facilitating the generation of environmentally friendly hydrogen. In this study, perovskite-type oxide containing praseodymium, barium, strontium, cobalt, and iron atoms dispersed in a carbon matrix as a catalyst is synthesized via annealing of the carbon material with substrates for the preparation of perovskite oxide. The mass ratio of reagents regulates the porous structure and elemental composition. The result of the hydrogen evolution reaction (HER), suggests that the hybrid catalysts exhibit intermediate HER kinetics compared to the commercial Pt/C and the catalyst without carbon. The Tafel slope for HER is lower for materials containing carbon, because of the improved reaction kinetics, facilitated proton transfer, and enhanced electrochemical surface area. Therefore, the study provides an effective strategy for the preparation of catalyst and their use as the active catalyst of water splitting.

  • Synteza oraz charakterystyka strukturalna i elektrochemiczna wieloskładnikowych nanokompozytów jako materiałów elektrodowych w urządzeniach do magazynowania energii
    • Anita Cymann
    2023 Pełny tekst

    W trakcie studiów doktoranckich prowadziłam badania strukturalne i elektrochemiczne materiałów elektrodowych zarówno do zastosowania w kondensatorach elektrochemicznych, jak i bateriach. Celem moich badań było wytworzenie wieloskładnikowych materiałów kompozytowych do zastosowań w urządzeniach magazynujących energię o dużej mocy. Łącząc ze sobą materiały o różnych sposobach magazynowania ładunku elektrycznego uzyskałam materiały kompozytowe o lepszych właściwościach elektrochemicznych (np. o wyższej pojemności) oraz strukturalnych (np. poprawa przewodności elektrycznej). Badałam między innymi wpływ dodatków węglowych na właściwości kompozytu opartego na matrycy z polimeru przewodzącego. Pojemności materiałów elektrodowych kondensatora elektrochemicznego badałam głównie w elektrolitach wodnych. Syntezowałam również związki o strukturze superprzewodników jonów sodu (fosforan sodowo-wanadowy) do zastosowania jako materiały katodowe w ogniwach sodowo-jonowych. Głównym celem była poprawa niskiej przewodności fosforanu sodowo-wanadowego poprzez równomierne rozmieszczenie materiału węglowego w próbce, co w efekcie pozwoliło na uzyskanie zarówno wyższej wartości pojemności jak i lepszej stabilności w trakcie pracy półogniwa.

  • Synteza poliuretanu z udziałem biomonomerów i jego recykling chemiczny
    • Marcin Włoch
    • Barbara Wojciechowska
    • Janusz Datta
    2023 Pełny tekst Przemysł Chemiczny

    Przeprowadzono recykling chemiczny (aminoliza i glikoliza) zsyntezowanego wcześniej poliuretanu, otrzymanego z wykorzystaniem surowców pochodzenia naturalnego, oraz zbadano podstawowe właściwości otrzymanych produktów depolimeryzacji chemicznej. Poliuretan otrzymano metodą prepolimerową, wykorzystując surowce pochodzenia naturalnego, czyli poliol PriplastTM 1838 i diizocyjanian TolonateTM X FLO 100. Łańcuchy prepolimeru uretanowego zostały przedłużone z wykorzystaniem 1,4-butanodiolu (BDO). Depolimeryzację prowadzono, stosując trietylenotetraminę (TETA) i glikol etylenowy (GE), przy stosunkach masowych poliuretanu do czynnika depolimeryzującego równych 2:1, 1:1 i 1:2. Strukturę chemiczną poliuretanu i otrzymanych produktów depolimeryzacji zweryfikowano z wykorzystaniem spektroskopii w podczerwieni z transformacją Fouriera (FTIR). Dla uzyskanych produktów recyklingu chemicznego oznaczono liczbę aminową oraz określono właściwości reologiczne i stabilność termiczną (z wykorzystaniem analizy termograwimetrycznej).

  • Synthesis and application of biomass-derived magnetic biochar catalyst for simultaneous esterification and trans-esterification of waste cooking oil into biodiesel: modeling and optimization
    • Samuel Latebo Majamo
    • Temesgen Amibo
    • Tesfaye Kassaw Bedru
    2023 Pełny tekst Materials for Renewable and Sustainable Energy

    This work created, characterized, and used a magnetic biochar catalyst that is both eco-friendly and very effective. Sugarcane bagasse was selected as primary raw material for catalyst preparation, because it is renewable and ecofriendly biomass. Cata- lyst created by doping sugarcane bagasse biochar with magnetic material in the form of (FeSO 4 ·7H 2 O). Thermogravimetric Analysis (TGA) and Fourier Transform Infrared spectroscopy (FTIR) were used to characterize the catalyst. In addition, physical and textural characteristics of the catalyst were identified and interpreted. The characterization outcome showed that the catalyst has good catalytic qualities. For the manufacturing of biodiesel, discarded cooking oil served as the primary feedstock. The experiment was created utilizing the Box–Behnken Design (BBD) technique. There are four variables with the following three levels each: temperature, methanol to oil ratio, catalyst concentration, and reaction time. 29 experiments in total were carried out. Using the RSM function, optimization was done. The optimal conditions for obtaining biodiesel yield—temperature, methanol to oil ratio, reaction time, and catalyst weight—were 43.597 °C, 9.975 mol/L, 49.945 min, and 1.758 wt%. A study of the produced biodiesel using a FTIR showed that the conventional biodiesel IR spectra were confirmed. All physiochemical characteristics found suggested the biodiesel complied with ASTM and EN norms. Overall, the synthesized catalyst had conducted simultaneous reactions in a single batch reactor and had demonstrated suitability for converting used cooking oil to biodiesel.

  • Synthesis and crystal structure of ferrocenyl benzothiazole derivatives
    • Yordan Stremski
    • Maria Bachvarova
    • Stela Statkova-Abeghe
    • Plamen Angelov
    • Iliyan Ivanov
    • Anife Ahmedova
    • Anna Dołęga
    2023 JOURNAL OF ORGANOMETALLIC CHEMISTRY

    Novel ferrocenyl-containing benzothiazole derivatives were synthesised in moderate yields by one-pot α-amidoalkylation of ferrocene. The reaction conditions were critically evaluated and the crystal structure of one of the amidoalkylated ferrocenes was resolved. Oxidation of the obtained compounds led to known fully aromatic 2-ferrocenylbenzothiazole in 81 % yield, which represents a convenient alternative to earlier methods utilizing cyclocondensation reactions.

  • Synthesis, Antimicrobial and Mutagenic Activity of a New Class of d-Xylopyranosides
    • Karol Sikora
    • Piotr Szweda
    • Karolina Słoczyńska
    • Justyna Samaszko-Fiertek
    • Janusz Madaj
    • Beata Liberek
    • Elżbieta Pękala
    • Barbara Dmochowska
    2023 Pełny tekst Antibiotics-Basel

    Eight N-[2-(2′,3′,4′-tri-O-acetyl-α/β-d-xylopyranosyloxy)ethyl]ammonium bromides, a new class of d-xylopyranosides containing a quaternary ammonium aglycone, were obtained. Their complete structure was confirmed using NMR spectroscopy (1H, 13C, COSY and HSQC) and high-resolution mass spectrometry (HRMS). An antimicrobial activity against fungi (Candida albicans, Candida glabrata) and bacteria (Staphylococcus aureus, Escherichia coli) and a mutagenic Ames test with Salmonella typhimurium TA 98 strain were performed for the obtained compounds. The greatest activity against the tested microorganisms was shown by glycosides with the longest (octyl) hydrocarbon chain in ammonium salt. None of the tested compounds exhibited mutagenic activity in the Ames test.

  • Synthesis, characterization, and application of 2D/2D TiO2-GO-ZnFe2O4 obtained by the fluorine-free lyophilization method for solar light-driven photocatalytic degradation of ibuprofen
    • Izabela Malinowska
    • Piotr Madajski
    • Adam Ostrowski
    • Cristina Gómez-Polo
    • Laura Carvera
    • Waldemar Bednarski
    • Paweł Kubica
    • Anna Zielińska-Jurek
    2023 Pełny tekst ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH

    In this study, we report the potential of 2D/2D TiO2- GO-ZnFe2O4 photocatalyst obtained using the fluorine-free lyophilization technique for the degradation of ibuprofen belonging to the group of active pharmaceutical ingredients (API). The improved ibuprofen degradation under simulated solar light was achieved in the presence of a composite of 2D TiO2 combined with GO and embedded ZnFe2O4, which additionally provides superparamagnetic properties and enables photocatalyst separation after the photodegradation process. After only 20 min of the photodegradation process in the presence of 2D/2D TiO2- GO-ZnFe2O4 composite, more than 90% of ibuprofen was degraded under simulated solar light, leading to non-toxic and more susceptible to biodegradation intermediates. At the same time, photolysis of ibuprofen led to the formation of more toxic intermediates. Furthermore, based on the photocatalytic degradation analysis, the degradation by-products and possible photodegradation pathways of ibuprofen were investigated. The photodegradation tests and electronic spin resonance analyses indicated the significant involvement of superoxide radicals and singlet oxygen in the ibuprofen photodegradation process.

  • Synthesis, Characterization and Biological Investigations of Half-Sandwich Ruthenium(II) Complexes Containing Benzimidazole Moiety
    • Patrycja Rogala
    • Agnieszka Jabłońska-Wawrzycka
    • Grzegorz Czerwonka
    • Katarzyna Kazimierczuk
    • Katarzyna Gałczyńska
    • Sławomir Michałkiewicz
    • Justyna Kalinowska-Tłuścik
    • Marta Karpiel
    • Karel D. Klika
    2023 Pełny tekst MOLECULES

    Half-sandwich Ru(II) complexes belong to group of biologically active metallo-compounds with promising antimicrobial and anticancer activity. Herein, we report the synthesis and characteri- zation of arene ruthenium complexes containing benzimidazole moiety, namely, [(η6-p-cymene)RuC l(bimCOO)] (1) and [(η6-p-cymene)RuCl2(bim)] (2) (where bimCOO = benzimidazole-2-carboxylate and bim = 1-H-benzimidazole). The compounds were characterized by 1H NMR, 13C NMR, IR, UV–vis and CV. Molecular structures of the complexes were determined by SC-XRD analysis, and the results indicated the presence of a pseudo-tetrahedral (piano stool) geometry. Interactions in the crystals of the Ru complexes using the Hirshfeld surface analysis were also examined. In addition, the biological studies of the complexes, such as antimicrobial assays (against planktonic and adherent microbes), cytotoxicity and lipophilicity, were performed. Antibacterial activity of the complexes was evaluated against S. aureus, E. coli, P. aeruginosa PAO1 and LES B58. Cytotoxic activity was tested against primary human fibroblasts and adenocarcinoma human alveolar basal epithelial cells. Obtained biological results show that the ruthenium compounds have bacteriostatic activity toward Pseudomonas aeruginosa PAO1 strain and are not toxic to normal cells. A molecular docking study was applied as a predictive source of information about the plausibility of examined structures binding with HSA as a transporting system.

  • Synthesis of 3-(2-Alkylthio-4-chloro-5-methylbenzenesulfonyl)-2-(1-phenyl-3-arylprop-2-enylideneamino)guanidine Derivatives with Pro-Apoptotic Activity against Cancer Cells
    • Aneta Pogorzelska
    • Jarosław Sławiński
    • Anna Kawiak
    • Grzegorz Stasiłojć
    • Jarosław Chojnacki
    2023 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    The untypical course of reaction between chalcones and benzenesulfonylaminoguanidines led to the new 3-(2-alkylthio-4-chloro-5-methylbenzenesulfonyl)-2-(1-phenyl-3-arylprop-2- enylideneamino)guanidine derivatives 8–33. The new compounds were tested in vitro for their impact on the growth of breast cancer cells MCF-7, cervical cancer cells HeLa and colon cancer cells HCT-116 by MTT assay. The results revealed that the activity of derivatives is strongly related to the presence of hydroxy group in the benzene ring at the 3-arylpropylidene fragment. The most cytotoxic compounds 20 and 24 displayed mean IC50 values of 12.8 and 12.7 uM, respectively, against three tested cell lines and were almost 3- and 4-fold more active toward MCF-7 and HCT-116 when compared with non-malignant HaCaT cells. Furthermore, compound 24 induced apoptosis in cancer cells and caused a decrease of mitochondrial membrane potential as well as an increase of cells in sub-G1 phase in contrast to its inactive analog 31. The strongest activity against the most sensitive HCT-116 cell line was found for compound 30 (IC50 = 8 uM), which was 11-fold more effective in the growth inhibition of HCT-116 cells than those of HaCaT cells. Based on this fact, the new derivatives may be promising leading structures for the search for agents for the treatment of colon cancer.

  • Synthesis of Cyano-Benzylidene Xanthene Synthons Using a Diprotic Brønsted Acid Catalyst, and Their Application as Efficient Inhibitors of Aluminum Corrosion in Alkaline Solutions
    • Amin Mohammed
    • Gaber Mersal
    • Morad El-Hendawy
    • Abdallah Shaltout
    • Ali Badawi
    • Johan Boman
    • Adil Gobouri
    • Murat Saracoglu
    • Fatma Kandemirli
    • Rabah Boukherroub
    • Jacek Ryl
    • Mohamed Khalifa
    2023 Pełny tekst MOLECULES

    Novel cyano-benzylidene xanthene derivatives were synthesized using one-pot and condensation reactions. A diprotic Brønsted acid (i.e., oxalic acid) was used as an effective catalyst for the promotion of the synthesis process of the new starting xanthene–aldehyde compound. Different xanthene concentrations (ca. 0.1–2.0 mM) were applied as corrosion inhibitors to control the alkaline uniform corrosion of aluminum. Measurements were conducted in 1.0 M NaOH solution using Tafel extrapolation and linear polarization resistance (LPR) methods. The investigated xanthenes acted as mixed-type inhibitors that primarily affect the anodic process. Their inhibition efficiency values were enhanced with inhibitor concentration, and varied according to their chemical structures. At a concentration of 2.0 mM, the best-performing studied xanthene derivative recorded maximum inhibition efficiency values of 98.9% (calculated via the Tafel extrapolation method) and 98.4% (estimated via the LPR method). Scanning electron microscopy (SEM) was used to examine the morphology of the corroded and inhibited aluminum surfaces, revealing strong inhibitory action of each studied compound. High-resolution X-ray photoelectron spectroscopy (XPS) profiles validated the inhibitor compounds’ adsorption on the Al surface. Density functional theory (DFT) and Monte Carlo simulations were applied to investigate the distinction of the anticorrosive behavior among the studied xanthenes toward the Al (111) surface. The non-planarity of xanthenes and the presence of the nitrile group were the key players in the adsorption process. A match between the experimental and theoretical findings was evidenced.

  • Synthesis of N-doped TiO2 nanoparticles with enhanced photocatalytic activity for 2,4-dichlorophenol degradation and H2 production
    • Javed Ali Khan
    • Murtaza Sayed
    • Noor S. Shah
    • Sanaullah Khan
    • Ashfaq Ahmad Khan
    • Muhammad Sultan
    • Ammar M. Tighezza
    • Jibran Iqbal
    • Grzegorz Boczkaj
    2023 Pełny tekst Journal of Environmental Chemical Engineering

    Nitrogen-doped titanium dioxide (N-TiO2) nanoparticles were prepared using a modified sol-gel method. The as-prepared nanoparticles were characterized by state-of-the-art techniques for their optical, structural and morphological properties. The crystallite size, surface area and bandgap energy of reference TiO2 and N-TiO2 nanoparticles were found to be 16.1 and 10.9 nm, 83.6 and 131.8 m2 g−1 and 3.23 and 2.89 eV, respectively. The photocatalytic activities, in terms of 2,4-dichlorophenol (2,4-DCP) degradation, of reference TiO2 and N-TiO2 were found to be 46.9% and 65.4% at 120 min of treatments under UV light irradiation and 21.5% and 77.6% at 240 min of treatment under visible light irradiation, employing 153.4 µM 2,4-DCP, 1 g/L photocatalyst dosage, and pH 5.6. Interestingly, considerable H2 production rate (i.e., 386 μmol h−1 g−1) was observed for visible/N-TiO2 system in presence of 0.2 wt% Pt. The study revealed that visible/N-TiO2 photocatalytic system can be used as an economically viable technology for environmental sustainability.

  • SYNTHESIZING MEDICAL TERMS – QUALITY AND NATURALNESS OF THE DEEP TEXT-TO-SPEECH ALGORITHM
    • Bożena Kostek
    • Barbara Szyca
    2023 Pełny tekst Journal of the Acoustical Society of America

    The main purpose of this study is to develop a deep text-to-speech (TTS) algorithm designated for an embedded system device. First, a critical literature review of state-of-the-art speech synthesis deep models is provided. The algorithm implementation covers both hardware and algorithmic solutions. The algorithm is designed for use with the Raspberry Pi 4 board. 80 synthesized sentences were prepared based on medical and everyday language employing the TTS algorithm. For tests, an application is built, containing a questionnaire allowing for evaluating the quality and naturalness of the synthesized speech, for both types of language. It is followed by the algorithm efficiency tests. A presentation of the performed tests, along with the results obtained from 30 respondents, is shown. The discussion consists of a statistical analysis of the obtained results and a comparison with other speech recognition solutions used as a reference. Finally, in the summary section, there is an overall conclusion of this approach and promising directions for future development. This work is supported by the Polish National Center for Research and Development (NCBR) project: “ADMEDVOICE-Adaptive intelligent speech processing system of medical personnel with the structuring of test results and support of therapeutic process,” no. INFOSTRATEG4/0003/2022.

  • System Loss Model for Body Area Networks in Room Scenarios
    • Manuel M. Ferreira
    • Filipe D. Cardoso
    • Sławomir Ambroziak
    • Mariella Särestöniemi
    • Luis M. Correia
    2023

    This paper presents an analysis of system loss in Body Area Networks for room scenarios, based on a wideband measurement campaign at 5.8 GHz. The measurements were performed with a fixed antenna transmitting vertically and horizontally polarised signals, while the user wears dualpolarised antennas. The average system losses in co- and crosspolarised channels are 41.4 and 42.6 dB for vertically polarised transmitted signals and 41.8 and 45.0 dB for horizontally ones, showing that polarisation plays a role in the radio channel. Analytical models for the average and standard deviation of system loss are presented, with a linear dependence on user mobility, on transmitted/received polarisation, and on link visibility and dynamics. Overall, a good fit between model and measurements is obtained, with a mean square error of 2.3 and 0.12 dB for the average and standard deviation, respectively.