Repozytorium publikacji - Politechnika Gdańska

Ustawienia strony

english
Repozytorium publikacji
Politechniki Gdańskiej

Pokaż publikacje z roku

Ostatnie pozycje

  • Effects of Ni-NCAL and Ni–Ag electrodes on the cell performances of low-temperature solid oxide fuel cells with Sm0.2Ce0·8O2-δ electrolyte at various temperatures
    • Sea-Fue Wang
    • Yi-Le Liao
    • Yung-Fu Hsu
    • Piotr Jasiński
    2022 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    Three low-temperature solid oxide fuel cells are built using Sm0.2Ce0·8O2-δ (SDC) as the electrolyte. Cell A is symmetrical and features Ni–LiNi0.8Co0·15Al0·05O2 (Ni–NCAL) electrodes, Cell B comprises a Ni–NCAL anode and a Ni–Ag cathode, and Cell C is fabricated using a Ni–NCAL cathode and a Ni–Ag anode. The ohmic resistance and polarization resistance (Rp) of Cells B and C are significantly higher than those of Cell A. The reduction of NCAL at the anodes of Cells A and B yields LiOH and Li2CO3 phases, and the Ni particles generated on the surfaces of the NCAL particles improve the catalytic activity of the cells. Li2CO3–LiOH melts at temperatures >450 °C and penetrates the porous SDC electrolyte layer, causing its densification and abnormal grain growth and increasing its ionic conductivity to >0.2 S/cm at low temperatures. The high open-circuit voltages (OCVs) (0.970–1.113 V) of the cells during electrochemical measurements are ascribed to the Li2CO3–LiOH phase which serves as an electron-blocking layer for the SDC electrolytes. As the reduction of NCAL approaches completion, the anode comprises only Ni phase, which hinders the charge transfer process. The triple-phase-boundary (TPB) area at cathode of Cell B is significantly lower than that of Cell A; therefore, the catalytic activity of Cell B for the oxygen reduction reaction is lower than that of Cell A. Consequently, the maximum power density (MPD) of Cell B is less than half of that of Cell A. The large Rp value of Cell C is ascribed to its low TPB area at Ni–Ag anode which has no reaction with H2 during operation. No visible sintering of the SDC electrolyte layer is observed for Cell C; therefore, its ionic conductivity is considerably smaller than those of the electrolyte layers of Cells A and B. The OCVs of Cell C (0.281–0.495 V) are significantly lower than the typical OCVs of ceria-based SOFCs. This is attributed to the porous SDC electrolyte layer of Cell C. The large Rp values and the low OCVs contribute to the low MPDs of Cell C at various temperatures.

  • Effects of Noncontact Shoulder Tool Velocities on Friction Stir Joining of Polyamide 6 (PA6)
    • Raheem Al-Sabur
    • Hassanein I. Khalaf
    • Aleksandra Świerczyńska
    • Grzegorz Rogalski
    • Hesamoddin Aghajani Derazkola
    2022 Pełny tekst Materials

    In this study, the effects of the traverse and rotational velocities of the noncontact shoulder tool on the heat generation and heated flux during the friction stir joining of high-density polyamide 6 (PA6) polymer were investigated. The computational fluid dynamics (CFD) method was employed to simulate the thermomechanical phenomena during the friction stir joining (FSJ) process of PA6. A developed model was used to consider the void formation and thermochemical properties of PA6. The surface and internal heat flow, material flow, and geometry of the joint were simulated, and an experimental study evaluated the simulation results. The simulation results indicated that the stir zone formed was smaller than regular joints with a noncontact shoulder tool. Despite the polymer’s traditional FSJ, heat generation and material flow do not differ significantly between advancing and retreating sides. On the other hand, the surface flow is not formed, and the surface temperature gradient is in a narrow line behind the tool. The material velocity increased at higher rotational speed and lower transverse velocity and in the stir zone with more giant geometry forms. The maximum generated heat was 204 C, and the maximum material velocity was predicted at 0.44 m/s in the stir zone, achieved at 440 rpm and 40 mm/min tool velocities.

  • Effects of Post-Harvest Elicitor Treatments with Ultrasound, UV- and Photosynthetic Active Radiation on Polyphenols, Glucosinolates and Antioxidant Activity in a Waste Fraction of White Cabbage (Brassica oleracea var. capitata)
    • Randi Seljåsen
    • Barbara Kusznierewicz
    • Agnieszka Bartoszek-Pączkowska
    • Jørgen Mølmann
    • Ingunn M. Vågen
    2022 Pełny tekst MOLECULES

    Biosynthesis of phytochemicals in leaves of Brassica can be initiated by abiotic factors. The aim of the study was to investigate elicitor treatments to add value to waste of cabbage. A leaf waste fraction from industrial trimming of head cabbage was exposed to UV radiation (250–400 nm, 59 and 99 kJ m-2, respectively), photosynthetic active radiation (PAR, 400–700 nm, 497 kJ m-2), and ultrasound in water bath (35 kHz, at 15, 30 and 61 kJ l-1 water), in order to improve nutraceutical concentration. UV was more effective than PAR to increase the level of flavonols (2 to 3-fold higher) and hydroxycinnamate monosaccharides (1 to 10-fold higher). PAR was three times as effective as UV to increase anthocyanins. Interaction of PAR +UV increased antioxidant activity (30%), the content of five phenolics (1.4 to 10-fold higher), and hydroxycinnamic monosaccharides (compared with PAR or UV alone). Indoles were reduced (40–52%) by UV, but the other glucosinolates (GLS) were unaffected. Ultrasound did not influence any parameters. The results are important for white cabbage by-products by demonstrating that UV + PAR can be successfully used as an effectual tool to increase important phenolics and antioxidant activity of waste fraction leaves without an adverse effect on the main GLS.

  • Effects of Surface Energy and Surface Residual Stresses on Vibro-Thermal Analysis of Chiral, Zigzag, and Armchair Types of SWCNTs Using Refined Beam Theory
    • Subrat Kumar Jena
    • S. Chakraverty
    • Mohammad Malikan
    • Francesco Tornabene
    2022 Pełny tekst MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES

    In this article, vibration characteristics of three different types of Single-Walled Carbon Nanotubes (SWCNTs) such as armchair, chiral, and zigzag carbon nanotubes have been investigated considering the effects of surface energy and surface residual stresses. The nanotubes are embedded in the elastic substrate of the Winkler type and are also exposed to low and high-temperature environments. A new refined beam theory namely, one-variable shear deformation beam theory has been combined with Hamilton’s principle to develop the governing equations of the proposed model. The size-dependent behavior of the SWCNTs is addressed by Eringen’s nonlocal elasticity theory whereas the model is investigated analytically by employing Navier’s technique. Also, a parametric study has been conducted to analyze the effects of various scaling parameters such as small scale parameter, temperature change, thermal environments, Winkler modulus, and length of the beam. The results are also validated with previously published articles in special cases witnessing robust agreement.

  • Effects of UV light irradiation on fluctuation enhanced gas sensing by carbon nanotube networks
    • Katarzyna Drozdowska
    • Adil Rehman
    • Aleksandra Krajewska
    • Dmitri V. Lioubtchenko
    • Krystian Pavłov
    • Sergey Rumyantsev
    • Janusz Smulko
    • Grzegorz Cywiński
    2022 Pełny tekst SENSORS AND ACTUATORS B-CHEMICAL

    The exceptionally large active surface-to-volume ratio of carbon nanotubes makes it an appealing candidate for gas sensing applications. Here, we studied the DC and low-frequency noise characteristics of a randomly oriented network of carbon nanotubes under NO2 gas atmosphere at two different wavelengths of the UV light-emitting diodes. The UV irradiation allowed to sense lower concentrations of NO2 (at least 1 ppm) compared to dark conditions. Our experimental studies confirmed that the flicker noise of resistance fluctuations under UV irradiation significantly enhanced the sensing characteristics of nanotube networks at low concentrations. We observed a dominating 1/f-like noise component below 1 kHz. The sensitivity of nanotube networks was higher for shorter wavelength, whereas drift in the resistance was smaller for longer wavelength. The measurements under the NO2 gas atmosphere revealed a remarkable reduction in DC resistance drift of the nanotube network between consecutive cycles of gas sensing. This phenomenon was explained via absorption-desorption of NO2 gas molecules on nanotubes surface. Since small concentrations of NO2 pose a threat to the ecosystem, these results might play a significant role in the development of sensitive nanotubes-based photo-activated gas sensors.

  • Efficacy of intralesional bleomycin in treatment resistant viral warts
    • Martyna Sławińska
    • Jakub Żółkiewicz
    • Krzysztof Pastuszak
    • Klaudia Zawadzka
    • Monika Sikorska
    • Roman Nowicki
    • Michał Sobjanek
    2022 Pełny tekst Przegląd Dermatologiczny

    Introduction Optimal management of treatment-refractory viral warts caused by human papillomavirus is unknown. One of the treatment methods is intralesional bleomycin solution. Objective To determine risk factors for resistant viral warts (not responding to conventional treatments for ≥ 6 months), to determine the effectiveness and safety of intralesional bleomycin in a group of patients with viral warts resistant to conventional treatment methods, and to assess the utility of dermoscopy in monitoring treatment effects during intralesional bleomycin therapy. Material and methods The study group consisted of consecutive 12 adult patients with resistant viral warts treated with intralesional bleomycin (0,5 U/ml) at the Department of Dermatology, Venereology and Allergology, Medical University of Gdansk between July 2019 and December 2021. Inclusion criteria were age > 18 and previous unsuccessful treatment of viral warts with ≥ 2 methods used according to guidelines over a period of 6 months. The control group consisted of 8 adult patients who presented with viral warts of the total duration of less than 6 months with no previous treatment, and qualified for cryotherapy. Results Bleomycin showed 100% efficacy. Except for periprocedural pain, no side effects were observed. Dermoscopy proved to be effective in clinical evaluation of patients, as it allowed to differentiate wart remnants from eschar observed after bleomycin injection. In one patient we observed CD4+ lymphocytopenia at the inclusion stage, and no other risk factors of resistant warts could be identified, however a relatively small number of patients studied could influence this observation. Conclusions Intralesional bleomycin may be considered as possible therapeutic option in patients with therapy-resistant viral warts.

  • Efficiency evaluation of graduation process in Australian public universities
    • Andrzej Szuwarzyński
    2022 Pełny tekst Economic Research-Ekonomska Istrazivanja

    First-year attrition and on-time graduation are key challenges for contemporary universities, which determine their efficiency. Based on the benefit of the doubt approach, this study reports the efficiency of the graduation process in 37 Australian public universities. The super-efficiency model extended by restrictions on virtual weights is used. The proposed model considers the attrition rate and the on-time graduation rate separately for domestic and overseas students and other variables, like student-staff ratio, the share of full-time students and the share of online students. Some additional factors are included, such as the university's affiliation with a grouping, the year of the university founding and basic data on the subject mix of universities courses, explaining the rankings created. The analysis indicates that research-oriented universities achieve better results and overseas students perform better than domestic ones. Also, it can be seen that the universities dealing with large-scale online learning are underperformed. The obtained results allow all stakeholders to understand better the efficiency of the graduation process. The main findings are consistent with research published elsewhere.

  • Efficiency of exciton splitting in organic photovoltaic cells within EQE spectrum
    • Grażyna Jarosz
    • Ryszard Signerski
    • Rafał Marczyński
    2022 Pełny tekst APPLIED SURFACE SCIENCE

    The paper presents a procedure of estimating the efficiency of exciton splitting at ED/EA interface. The procedure consists in evaluation of splitting of excitons into electron-hole pairs on the basis of the external quantum efficiency spectra of planar cells and spectra of absorbance of active organic layers. The fitting parameters are the exciton splitting probabilities at ED/EA interface. The presented procedure was applied to two different photovoltaic systems: ITO/MoO3/DBP/PTCBI/BCP/Ag and ITO/MoO3/DBP/F16ZnPc/BCP/Ag with quite similar energy diagrams at the ED/EA interface. The analysis performed led us to the conclusion that only the DBP/PTCBI interface can be considered attractive for organic photovoltaics and organic photodetection, while the DBP/F16ZnPc interface does not show any favourable properties for such applications.

  • Efficient and robust quadratures for isogeometric analysis: Reduced Gauss and Gauss–Greville rules
    • Z. Zou
    • T.j.r. Hughes
    • M.a. Scott
    • D. Miao
    • Roger Sauer
    2022 Pełny tekst COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING

    This work proposes two efficient quadrature rules, reduced Gauss quadrature and Gauss–Greville quadrature, for isogeometric analysis. The rules are constructed to exactly integrate one-dimensional B-spline basis functions of degree p, and continuity class C^{p−k}, where k is the highest order of derivatives appearing in the Galerkin formulation of the problem under consideration. This is the same idea we utilized in Zou et al. (2021), but the rules therein produced negative weights for certain non-uniform meshes. The present work improves upon Zou et al. (2021) in that the weights are guaranteed to be positive for all meshes. The reduced Gauss quadrature rule is built element-wise according to the element basis degree and smoothness. The Gauss– Greville quadrature rule combines the proposed reduced Gauss quadrature and Greville quadrature Zou et al. (2021). Both quadrature rules involve many fewer quadrature points than the full Gauss quadrature rule and avoid negative quadrature weights for arbitrary knot vectors. The proposed quadrature rules are stable and accurate, and they can be constructed without solving nonlinear equations, therefore providing efficient and easy-to-use alternatives to full Gauss quadrature. Various numerical examples, including curved shells, demonstrate that they achieve good accuracy, and for p = 5 and 6 eliminate locking.

  • Efficient Extraction of Fermentation Inhibitors by Means of Green Hydrophobic Deep Eutectic Solvents
    • Patrycja Makoś-Chełstowska
    • Edyta Słupek
    • Karolina Kucharska
    • Aleksandra Kramarz
    • Jacek Gębicki
    2022 Pełny tekst MOLECULES

    The methods for hydrogen yield efficiency improvements, the gaseous stream purification in gaseous biofuels generation, and the biomass pretreatment are considered as the main trends in research devoted to gaseous biofuel production. The environmental aspect related to the liquid stream purification arises. Moreover, the management of post-fermentation broth with the application of various biorefining techniques gains importance. Chemical compounds occurring in the exhausted liquid phase after biomass pretreatment and subsequent dark and photo fermentation processes are considered as value-added by products. The most valuable are furfural (FF), 5-hydroxymethylfurfural (HMF), and levulinic acid (LA). Enriching their solutions can be carried with the application of liquid–liquid extraction with the use of a suitable solvent. In these studies, hydrophobic deep eutectic solvents (DESs) were tested as extractants. The screening of 56 DESs was carried out using the Conductor-like Screening Model for Real Solvents (COSMO-RS). DESs which exposed the highest inhibitory effect on fermentation and negligible water solubility were prepared. The LA, FF, and HMF were analyzed using FT-IR and NMR spectroscopy. In addition, the basic physicochemical properties of DES were carefully studied. In the second part of the paper, deep eutectic solvents were used for the extraction of FF, LA, and HMF from post-fermentation broth (PFB). The main extraction parameters, i.e., temperature, pH, and DES: PFB volume ratio (VDES:VPFB), were optimized by means of a Box–Behnken design model. Two approaches have been proposed for extraction process. In the first approach, DES was used as a solvent. In the second, one of the DES components was added to the sample, and DES was generated in situ. To enhance the post-fermentation broth management, optimization of the parameters promoting HMF, FF, and LA extraction was carried under real conditions. Moreover, the antimicrobial effect of the extraction of FF, HMF, and LA was investigated to define the possibility of simultaneous separation of microbial parts and denatured peptides via precipitation.

  • Efficient Fabry-Perot Open Resonator Analysis by the use of a Scattering Matrix Method
    • Małgorzata Warecka
    • Sebastian Dziedziewicz
    • Piotr Kowalczyk
    • Rafał Lech
    • Piotr Czekala
    • Bartlomiej Salski
    • Pawel Kopyt
    2022

    In this paper a comparative study of the computational efficiency of two modeling methods applied to the analysis of the plano- and double-concave Fabry-Perot open resonators is presented. In both numerical approaches, a scattering matrix method was applied, which allows splitting the analysis of the resonator into several sections, including the one with a spherical mirror, which requires the largest computing resources. Two modeling techniques were utilized to evaluate the scattering matrix of the spherical mirror, namely, the finite element method and free-space Green's function method. Resonant frequencies and the corresponding field distributions of the selected Gaussian modes were calculated and compared. Good agreement between the methods was achieved; however, the Green's function method has occurred to be more computationally efficient.

  • Efficient FPGA Implementation of an RFIR Filter Using the APC–OMS Technique with WTM for High-Throughput Signal Processing
    • Kasarla Satish Reddy
    • Sowmya Madhavan
    • Przemysław Falkowski-Gilski
    • Parameshachari Bidare Divakarachari
    • Arun Mathiyalagan
    2022 Pełny tekst Electronics

    Nowadays, Finite Impulse Response (FIR) filters are used to change the attributes of a signal in the time or frequency domain. Among FIR filters, a reconfigurable filter has the advantage of changing the coefficient in real-time, while performing the operation. In this paper, the Anti-Symmetric Product Coding (APC) and Odd Multiple Storage (OMS) modules are utilized to implement the reconfigurable FIR filter (RFIR–APC–OMS). Herein, the APC–OMS module is used to reduce the area of the RFIR architecture. The performance of the RFIR–APC–OMS is analyzed in terms of: area, power, delay, LUT, flip flop, slices, and frequency. RFIR–APC–OMS has reduced 3.44% of area compared to the existing RFIR architecture employing the Dynamic Reconfigurable Partial Product Generator (DRPPG) module.

  • Ekonomika i zarządzanie energią
    • Waldemar Kamrat
    2022

    Przedstawiono problematykę kosztów w sektorze energii. Opisano metody oceny efektywności inwestowania.Przedstawiono problematykę audytingu energetycznego oraz pokazana współczesne narzędzia zarzadzania energią

  • Eko-regionalizm w architekturze wsi – idea czy realna szansa odbudowy wiejskości?
    • Anna Górka
    2022 Kultura wsi Ludzie Wydarzenia Przemiany

    Artykuł jest refleksją nad możliwością odrodzenia lokalnych form budownictwa wiejskiego dzięki rozwojowi architektury proekologicznej: "Swoisty eko-regionalizm w architekturze i budownictwie może wzmocnić odbudowę lokalnej specyfiki i lokalnej gospodarki wielu miejscowości. Wyrazisty wizerunek miejsca, kreowany przez architekturę i inne elementy zagospodarowania, sprzyja formowaniu tożsamości społecznej, poczuciu wspólnoty i rozwojowi lokalnemu."

  • EKOSYSTEM PRZESTRZENI ZAMIESZKIWANIA W UJĘCIU AUTORSKICH POSZUKIWAŃ FORMY DOMU OPARTYCH O KONCEPCJĘ ZGODNOŚCI
    • Agnieszka Kurkowska
    2022 Pełny tekst

    Celem artykułu jest prezentacja efektów projektu autorskiego realizowanego w oparciu o koncepcję zgodności. Przeprowadzone zostały kilkuletnie studia lokalnych uwarunkowań przyrodniczych skutkujących powstaniem zbioru rysunków i rzeźb oraz fotografii dokumentujących ich aranżację in situ. Badania prowadzono na terenie Pojezierza Kaszubskiego w obszarze południowego brzegu Jeziora Wdzydzkiego. Działania artystyczno-projektowe o charakterze biofilicznym i biomimetycznym lokują się w nurcie badań bionicznych. Wykonane analizy i dokumentacja stanowi pierwszy element pracy, która w dalszym przebiegu posłuży tworzeniu koncepcyjnych obiektów architektonicznych, stanowiących propozycję dla kulturowej ingerencji w badany obszar przy założeniu uzyskania zgodności z zasiedlanym miejscem i istniejącym już ekosystemem. Współczesne kryzysy wskazują, że może być to alternatywny kierunek dla prośrodowiskowego projektowania obiektów mieszkalnych na obszarach zalesionych.

  • Electrical safety in low-voltage DC microgrids with B-type residual current devices
    • Stanisław Czapp
    • Hanan Tariq
    • Seweryn Szultka
    • Agata Szultka
    • Elena Zaitseva
    • Vitaly Levashenko
    2022 Pełny tekst Eksploatacja i Niezawodność - Maintenance and Reliability

    Residual current devices (RCDs) are most popular devices used in low-voltage installations for protection against electric shock and fire. In cases of high risk of electric shock the application of RCDs is mandatory. Currently, the spread of local direct current (DC) microgrids is widely considered. This creates new challenges for protective systems, in particular those based on RCDs. The main purpose of the research is to test the operation of B-type RCDs by simulating the conditions that may occur in DC microgrids as well as assessment of the effectiveness of electrical safety with the use of such RCDs. The research has revealed that theoretically identical RCDs in terms of technical data can have different tripping properties, including no reaction to residual direct current, which poses a risk of electric shock. This signalizes the necessity of extension of the normative tests performed by manufacturers. The scope of these additional RCDs tests is indicated, from the point of view of the persons’ safety in DC microgrids.

  • Electrocatalytic oxidation of methanol, ethylene glycol and glycerine in alkaline media on TiO2 nanotubes decorated with AuCu nanoparticles for an application in fuel cells
    • Wiktoria Lipińska
    • Katarzyna Grochowska
    • Jakub Karczewski
    • Emerson Coy
    • Katarzyna Siuzdak
    2022 JOURNAL OF MATERIALS SCIENCE

    In this work, we present the catalytic and photocatalytic activity of AuCu nanostructures obtained on TiO2 nanotubes toward methanol, ethylene glycol and glycerine oxidation. The electrode material is prepared by anodization of Ti foil, thin AuCu layer sputtering and rapid thermal treatment under argon atmosphere. Scanning electron microscopy images confirmed the presence of ordered tubular architecture of TiO2 as well as nanoparticles formed on the surface of the nanotubes. The electrodes were measured using cyclic voltammetry, linear voltammetry and electrochemical impedance spectroscopy in dark and under illumination. Obtained results show a significant current increase: 20 and 90 times higher current density at ? 0.3 V versus Ag/AgCl/0.1 M KCl after glycol and glycerine addition, respectively. Moreover, a higher current toward alcohol oxidation was registered for thermally annealed samples than for nonannealed ones. Reported studies demonstrate deep insight into the electrical properties of AuCu-modified titania materials.

  • Electrocatalytic performance of oxygen-activated carbon fibre felt anodes mediating degradation mechanism of acetaminophen in aqueous environments
    • Paweł Jakóbczyk
    • Grzegorz Skowierzak
    • Iwona Kaczmarzyk
    • Małgorzata Nadolska-Dawidowska
    • Anna Wcisło
    • Katarzyna Lota
    • Robert Bogdanowicz
    • Tadeusz Ossowski
    • Paweł Rostkowski
    • Grzegorz Lota
    • Jacek Ryl
    2022 Pełny tekst CHEMOSPHERE

    Carbon felts are flexible and scalable, have high specific areas, and are highly conductive materials that fit the requirements for both anodes and cathodes in advanced electrocatalytic processes. Advanced oxidative modi- fication processes (thermal, chemical, and plasma-chemical) were applied to carbon felt anodes to enhance their efficiency towards electro-oxidation. The modification of the porous anodes results in increased kinetics of acetaminophen degradation in aqueous environments. The utilised oxidation techniques deliver single-step, straightforward, eco-friendly, and stable physiochemical reformation of carbon felt surfaces. The modifica- tions caused minor changes in both the specific surface area and total pore volume corresponding with the surface morphology. A pristine carbon felt electrode was capable of decomposing up to 70% of the acetaminophen in a 240 min electrolysis process, while the oxygen-plasma treated electrode achieved a removal yield of 99.9% estimated utilising HPLC-UV-Vis. Here, the electro-induced incineration kinetics of acetaminophen resulted in a rate constant of 1.54 h, with the second-best result of 0.59 h-1 after oxidation in 30% H2O2. The kinetics of acetaminophen removal was synergistically studied by spectroscopic and electrochemical techniques, revealing various reaction pathways attributed to the formation of intermediate compounds such as p-aminophenol and others. The enhancement of the electrochemical oxidation rates towards acetaminophen was attributed to the appearance of surface carbonyl species. Our results indicate that the best-performing plasma-chemical treated CFE follows a heterogeneous mechanism with only approx. 40% removal due to direct electro-oxidation. The degradation mechanism of acetaminophen at the treated carbon felt anodes was proposed based on the detected intermediate products. Estimation of the cost-effectiveness of removal processes, in terms of energy consumption, was also elaborated. Although the study was focussed on acetaminophen, the achieved results could be adapted to also process emerging, hazardous pollutant groups such as anti-inflammatory pharmaceuticals.

  • Electrochemical determination of neurotransmitter serotonin using boron/nitrogen co-doped diamond-graphene nanowall-structured particles
    • Suchanat Boonkaew
    • Anna Dettlaff
    • Michał Sobaszek
    • Robert Bogdanowicz
    • Martin Jönsson-Niedziółka
    2022 Pełny tekst JOURNAL OF ELECTROANALYTICAL CHEMISTRY

    Electrode fouling is a major issue in biological detection due to the adhesion of the protein itself and polymerization of biomolecules on the electrode surface, impeding the electron transfer ability and decreasing the current response. To overcome this issue, the use of anti-fouling material, especially boron-doped diamond (BDD) electrode, is an alternative way. However, the electrocatalytic activity of BDD is inadequate compared with graphene nanowalls, or other sp2 phase materials. Furthermore, the contamination from other metals during the synthesis of BDD can affect the electrochemical analysis. Herein, for the first time, we report boron/nitrogen co-doped with diamond graphene nanowalls (DGNW) integrated with the screen-printed graphene electrode (SPGE) for the detection of serotonin (5-HT) as a model system. DGNW shows the integration of sp2 and sp3 hybridized phases, leading to a high surface area, high electrocatalytic activity, wide potential window, and a low background current. DGNWs prepared under different conditions were investigated and characterized. Compared to the bare SPGEs, the DGNW modified electrode exhibited good electrochemical performance and a superior anti-fouling ability for neurotransmitter detection. A significant enhancement in current response in a concentration-dependent manner was obtained using differential pulse voltammetry (DPV) in the presence of 5-HT from 1 to 500 μM (R2 > 0.99) with a low detection limit (0.28 μM). Moreover, this proposed method was applied in a synthetic urine sample to confirm its biological applicability. These results show that the DGNW modified electrode could be productively utilized as an alternative electrochemical transducer with a good anti-fouling performance.

  • Electrochemical investigations on corosivity of de-icing liquids for railway infrastructure
    • Karolina Brzóska
    • Dorota Sikorska
    • Stefan Krakowiak
    2022 Ochrona przed Korozją

    The paper presents the results of electrochemical tests of the de-icing fluid for railway infrastructure. DC and AC electrochemical tests were performed to determine the corrosion rates of structural steel, cast iron and aluminium in the newly produced fluid. The results were compared with the corrosion rates of the same materials in the fluid without corrosion inhibitors. The obtained test results indicate a low corrosion risk of the de-icing fluid in the railway infrastructure in relation to the tested materials. The components of the fluid cause the surface passivation of materials that normally corrode in the active state. The efficiency of the inhibitors contained in the tested fluids reached a value of 90%. Corrosion rates obtained for the tested materials are many times lower than acceptable. The corrosion rates in the fluid without inhibitors, due to polyols used, are also very low. Research by electrochemical impedance spectroscopy (EIS) showed high values of the charge transfer resistance and increase in material resistance along with the time of action of the fluids.

  • Electrochemical oxidation of landfill leachate using boron-doped diamond anodes: pollution degradation rate, energy efficiency and toxicity assessment
    • Barbara Wilk
    • Małgorzata Szopińska
    • Michał Sobaszek
    • Mattia Pierpaoli
    • Agata Błaszczyk
    • Aneta Łuczkiewicz
    • Sylwia Fudala-Książek
    2022 Pełny tekst ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH

    Electrochemical oxidation (EO), due to high efficiency and small carbon footprint, is regarded as an attractive option for on-site treatment of highly contaminated wastewater. This work shows the effectiveness of EO using three boron-doped diamond electrodes (BDDs) in sustainable management of landfill leachate (LL). The effect of the applied current density (25–100 mA cm−2) and boron doping concentration (B/C ratio: 500 ppm, 10,000 ppm and 15,000 ppm) on the performance of EO was investigated. It was found that, of the electrodes used, the one most effective at COD, BOD20 and ammonia removal (97.1%, 98.8% and 62%, respectively) was the electrode with the lowest boron doping. Then, to better elucidate the ecological role of LLs, before and after EO, cultivation of faecal bacteria and microscopic analysis of total (prokaryotic) cell number, together with ecotoxicity assay (Daphnia magna, Thamnocephalus platyurus and Artemia salina) were combined for the two better-performing electrodes. The EO process was very effective at bacterial cell inactivation using each of the two anodes, even within 2 h of contact time. In a complex matrix of LLs, this is probably a combined effect of electrogenerated oxidants (hydroxyl radicals, active chlorine and sulphate radicals), which may penetrate into the bacterial cells and/or react with cellular components. The toxicity of EO-treated LLs proved to be lower than that of raw ones. Since toxicity drops with increased boron doping, it is believed that appropriate electrolysis parameters can diminish the toxicity effect without compromising the nutrient-removal and disinfection capability, although salinity of LLs and related multistep-oxidation pathways needs to be further elucidated.

  • Electrochemical synthesis of 2D copper coordination-polymers: Layer-stacking deviation induced by the solvent and its effect on the adsorptive properties
    • Arthur Felipe de Farias Monteiro
    • Stephany Larissa da Silva Ribeiro
    • Thiago Izidoro Silva Santos
    • José Daniel da Silva Fonseca
    • Natalia Łukasik
    • Joanna Kulesza
    • Bráulio Silva Barros
    2022 Pełny tekst MICROPOROUS AND MESOPOROUS MATERIALS

    A 2D Cu-based Metal-Organic Framework (MOF), namely copper-terephthalate (Cu(1,4-BDC)), was successfully synthesized by electrochemical method for effective methylene blue (MB) sorption from aqueous solutions. The composition, morphology, and the presence of functional groups in the obtained material were verified by Fourier Transform Infrared spectroscopy (FTIR), Powder X-Ray Diffraction (PXRD), Thermal (TGA), and Elemental (EA) analysis, as well as Scanning Electron Microscopy (SEM). The effect of electrochemical param- eters applied in the synthesis protocol (i.e., a potentiometric or amperometric mode) on the resulting product composition was evaluated. The electric current value was determined as a variable controlling the type of crystal structure present in the obtained MOF. A structure with open channels - CuBDC1 was favored under the current higher than 0.35 A conditions. In contrast, for the lower current values and upon the amperometric mode in the material, a CuBDC2 phase with DMF molecules occupying the grids of the layers was also present. The MB sorption studies were analyzed both with kinetic and equilibrium models. The obtained results showed the time evolution could be fitted with a pseudo-second-order model with the rate constant k2 equal to 0.047 g μmol.

  • Electrolytic deposition of reactive element thin films on Crofer 22 APU and evaluation of the resulting high-temperature corrosion protection properties at 700 °C–900 °C
    • Bartłomiej Lemieszek
    • Justyna Ignaczak
    • Bartosz Kamecki
    • Jakub Karczewski
    • Mogens Mogensen
    • Sebastian Molin
    • Piotr Jasiński
    2022 Pełny tekst INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    This article presents electrolytic deposition of thin Rare Earth (RE) coatings on Crofer 22 APU stainless steel substrates for high temperature applications, such as interconnects in solid oxide cell stacks. The deposition of coatings based on yttrium-, gadolinium-, lanthanum-, and cerium nitrates is discussed. The high temperature corrosion properties of surface-modified steels were examined using thermogravimetry and electrical resistivity measurements. Coatings and oxide microstructures were examined by XRD and SEM of surfaces and cross-sections. The results showed that the use of the RE element oxide layers reduced the growth of oxide scale, as evidenced by lower weight gain. The layers based on Y- and Gd-oxides showed the best corrosion protection properties. The electrical measurements showed that the surface-modified samples had lower resistance than the uncoated sample.

  • Electromagnetic Control and Dynamics of Generalized Burgers’ Nanoliquid Flow Containing Motile Microorganisms with Cattaneo–Christov Relations: Galerkin Finite Element Mechanism
    • Faisal Shahzad
    • Wasim Jamshed
    • Tanveer Sajid
    • Md Shamshuddin
    • Rabia Safdar
    • Os Salawu
    • Mohamed Eid
    • Muhammad Bilal Hafeez
    • Marek Krawczuk
    2022 Pełny tekst Applied Sciences-Basel

    In our research work, we have developed a model describing the characteristics of the bio-convection and moving microorganisms in the flows of a magnetized generalized Burgers’ nanoliquid with Fourier’s and Fick’s laws in a stretchable sheet. Considerations have been made to Cattaneo–Christov mass and heat diffusion theory. According to the Cattaneo–Christov relation, the Buongiorno phenomenon for the motion of a nanoliquid in the generalized Burgers’ fluid has also been applied. Similarity transformations have been used to convert the control system of the regulating partial differential equations (PDEs) into ordinary differential equations (ODEs). The COMSOL software has been applied to obtain mathematical results of non-linear equations via the Galerkin finite element method (G-FEM). Logical and graphical measurements for temperature, velocity, and microorganisms analysis have also been examined. Moreover, nanoparticle concentrations have been achieved by examining different approximations of obvious physical parameters. Computations of this model show that there is a direct relationship among the temperature field and thermal Biot number and parameter of the generalized Burgers’ fluid. The temperature field is increased to grow the approximations of the thermal Biot number and parameter of generalized Burgers’ fluid. It is reasonable to deduce that raising the chemical reaction parameter and concentricity relaxation parameter or decreasing the Prandtl number, concentricity Biot quantity, and active energy parameter can significantly increase the nanoparticles concentration dispersion.

  • Electromagnetic Simulations with 3D FEM and Intel Optane Persistent Memory
    • Maciej Jakubowski
    • Piotr Sypek
    2022 Pełny tekst

    Abstract—Intel Optane persistent memory has the potential to induce a change in how high-performance calculations requiring a large system memory capacity are conducted. This article presents what this change may look like in the case of factorization of large sparse matrices describing electromagnetic problems arising in the 3D FEM analysis of passive highfrequency components. In numerical tests, the Intel oneAPI MKL PARDISO was used to solve relatively large electromagnetic problems defined using the finite element method.

  • Electronic nose algorithm design using classical system identification for odour intensity detection
    • Tomasz Zubowicz
    • Krzysztof Armiński
    • Bartosz Szulczyński
    • Jacek Gębicki
    2022 MEASUREMENT

    The two elements considered crucial for constructing an efficient environmental odour intensity monitoring systems are sensors and algorithms typically addressed to as electronic nose sensor (e-nose). Due to operational complexity of biochemical sensors developed in human bodies algorithms based on computational methods of artificial intelligence are typically considered superior to classical model based approaches in development of e-nose algorithms. However, in this work authors proposed an approach to derive an algorithm for e-nose using a classical approach kept in model identification framework. The benefits of the proposed solution, apart of the structural correctness of the derived algorithm model, include improved generalisation capabilities in case of low training data volume is available. To that goal the algorithm structure is derived based on available knowledge on human senses reaction to odorants. Due to the algorithm structure a random search algorithm with heuristics (evolutionary algorithm) is used to search for the required parameters of the electronic nose e-nose to be able to explain the laboratory experiment data. The evolutionary algorithm is kept in a multi-objective optimisation framework. As such, two heuristic decision making mechanisms have been proposed to select parameters for the algorithm under development. A comparison of the resulting algorithm with the one developed based on artificial neural networks (ANNs) is provided.

  • Electronic States of Tris(bipyridine) Ruthenium(II) Complexes in Neat Solid Films Investigated by Electroabsorption Spectroscopy
    • Daniel Pelczarski
    • Oleksandr Korolevych
    • Błażej Gierczyk
    • Maciej Zalas
    • Małgorzata Makowska-janusik
    • Waldemar Stampor
    2022 Pełny tekst Materials

    We present the electric field-induced absorption (electroabsorption, EA) spectra of the solid neat films of tris(bipyridine) Ru(II) complexes, which were recently functionalized in our group as photosensitizers in dye-sensitized solar cells, and we compare them with the results obtained for an archetypal [Ru(bpy)3]2+ ion (RBY). We argue that it is difficult to establish a unique set of molecular parameter values by discrete parametrization of the EA spectra under the Liptay formalism for non-degenerate excited states. Therefore, the experimental EA spectra are compared with the spectra computed by the TDDFT (time-dependent density-functional theory) method, which for the first time explains the mechanism of electroabsorption in tris(bipyridine) Ru complexes without any additional assumptions about the spectral lineshape of the EA signal. We have shown that the main EA feature, in a form close to the absorption second derivative observed in the spectral range of the first MLCT (metal-to-ligand charge transfer) absorption band in Ru(bpy)3(PF6)2, can be attributed to a delocalized and orbitally degenerate excited state. This result may have key implications for the EA mechanism in RBY-based systems that exhibit similar EA spectra due to the robust nature of MLCT electronic states in such systems.

  • Electrophoretic co-deposition of Mn1.5Co1.5O4, Fe2O3 and CuO: Unravelling the effect of simultaneous addition of Cu and Fe on the microstructural, thermo-mechanical and corrosion properties of in-situ modified spinel coatings for solid oxide cell interconnects
    • Elisa Zanchi
    • Justyna Ignaczak
    • Sebastian Molin
    • Grzegorz Cempura
    • A Boccaccini
    • Federico Smeacetto
    2022 JOURNAL OF THE EUROPEAN CERAMIC SOCIETY

    A systematic microstructural, thermo-mechanical and electrical characterization of simultaneous Fe–Cu doped Mn–Co spinel coatings processed by electrophoretic co-deposition on Crofer 22 APU is here reported and discussed. An innovative approach for the simultaneous electrophoretic deposition of three spinel precursors is designed, conceived and optimised, with the aim of outlining time- and energy-saving spinel modification routes. The effect of different levels of Cu and Fe co-doping is observed on the stability of the modified Mn–Co spinel phase, the coefficient of thermal expansion (CTE), the corrosion resistance and on the densification behaviour of the obtained coatings. Cu determines an increase of CTE, while Fe has the opposite behavior. The synergic effect of the simultaneous Fe and Cu co-doping results in an improved densification and the stabilization of the MnCo2O4 cubic phase. The most interesting results in terms of corrosion resistance are obtained for the Mn1.28Co1.28Fe0.15Cu0.29O4 spinel.

  • Elektrochemiczne magazyny energii - baterie przepływowe typu "redox flow"
    • Joanna Krakowiak
    • Krzysztof Rafał
    2022

    Rozwój i wzrost udziału energii odnawialnej, ze względu na kurczące się zasoby konwencjonalnych źródeł energii i ochronę środowiska, jest możliwy tylko dzięki współpracującym z nimi odpowiednim stacjonarnym magazynom energii. Technologia baterii przepływowych (ang. redox flow batteries, RFB) pozwala świetnie zaspokoić tego typu potrzeby ze względu na: (i) wyjątkowo dużą skalowalność układów; (ii) niezależny dobór mocy i pojemności energetycznej; (iii) możliwość rozbudowy w czasie eksploatacji; (iv) łatwość i bezpieczeństwo obsługi; (v) długi czas eksploatacji niezależny od głębokości rozładowania; (vi) wysoką sprawność; (vii) możliwość regeneracji elektrolitu; (viii) pomijalnie mały stopień samorozładowania niezależnie od stopnia naładowania baterii. Niniejsza praca ma na celu przybliżenie obecnego stanu wiedzy nt. baterii przepływowych oraz ich zastosowań komercyjnych.

  • Elucidating the impact of enzymatic modifications on the structure, properties, and applications of cellulose, chitosan, starch and their derivatives: a review
    • Zahra Shokri
    • Farzad Seidi
    • Mohammad Saeb
    • Yongcan Jin
    • Chengcheng Li
    • Huining Xiao
    2022 Materials Today Chemistry

    Polysaccharides, as one of the most prominent natural biopolymers, display numerous biological activities and industrial applications. Nevertheless, some polysaccharides lack biological properties or display weak biological activities. Besides, practical usages of polysaccharides still remain challenging because of their poor solubility and inappropriate hydrophilic/hydrophobic balance. Hence, enzymatic or chemical modifications have been emerged to improve physicochemical and biological properties of polysaccharides by altering their structural and conformational features, and consequently to enlarge their industrial applications. Compared to chemical methods, enzymatic modifications have drawn more attention owing to decreasing the input energy and environmental pollution, as well as high specificity and selectivity. The present review describes different reactions, including hydrolysis, esterification, transesterification, polymer, and phenolics grafting, for the modification of cellulose, chitosan, starch and their derivatives by catalysis with free and immobilized enzymes. Beyond the reaction types and the enzymes, the properties and potential applications of the obtained products are also reviewed.

  • EM-Driven Size Reduction and Multi-Criterial Optimization of Broadband Circularly-Polarized Antennas Using Pareto Front Traversing and Design Extrapolation
    • Ullah Ubaid
    • Muath Al-hasan
    • Sławomir Kozieł
    • Ismail Mabrouk
    2022 Pełny tekst Scientific Reports

    Maintaining small size has become an important consideration in the design of contemporary antenna structures. In the case of broadband circularly polarized (CP) antennas, miniaturization is a challenging process due to the necessity of simultaneous handling of electrical and field properties (reflection, axial ratio, gain), as well as ensuring sufficient frequency range of operation, especially at the lower edge of the antenna bandwidth. An additional difficulty is that—for the sake of reliability—the design process has to be based on full-wave electromagnetic (EM) simulation tools. This is a computationally expensive endeavor because rendering the minimum-size design under the assumed constraints concerning the operating frequencies requires rigorous numerical optimization, which entails massive evaluations of the structure at hand. This paper describes an algorithmic framework for efficient identification of broadband CP antenna designs that realize the best possible trade-offs (Pareto set) between the antenna size and its operating bandwidth. The designs are generated sequentially by solving local optimization tasks targeting explicit reduction of the antenna footprint with implicit constraints imposed on the reflection and axial ratio characteristics. The data accumulated during the previous iterations is employed to yield good initial points for further stages by means of inverse surrogates and extrapolation. Low cost of the process is ensured by sparse sensitivity updates within the trust-region gradient-based algorithm being the main optimization engine. The proposed methodology is demonstrated using three examples of wide-slot CP structures with the trade-off designs representing broad ranges of achievable antenna sizes and operating bandwidth. The framework can be used to assess the antenna suitability for particular application areas as well to conclusively compare alternative CP geometries from the point of view of achievable miniaturization rate and capability of fulfilling given performance requirements.

  • Emergency condition of the ceramic facade of a residential building
    • Maciej Niedostatkiewicz
    2022 Pełny tekst Modern Engineering

    The paper presents a description of the technical condition of the ceramic cladding of a residential building, the technical condition of which deteriorated significantly after only a few years of operation. The analysis of the influence of the applied design and working solutions on the façade failure frequency was analyzed. The article presents a conceptual solution to bring the building to the proper technical condition in terms of defects and damage to the facade.

  • Emergency condition of the ceramic facade of a residential building
    • Maciej Niedostatkiewicz
    2022 Pełny tekst Inżynieria Bezpieczeństwa Obiektów Antropogenicznych

    The paper presents a description of the technical condition of the ceramic cladding of a residential building, the technical condition of which deteriorated significantly after only a few years of operation. The analysis of the influence of the applied design and working solutions on the façade failure frequency was analyzed. The article presents a conceptual solution to bring the building to the proper technical condition in terms of defects and damage to the facade.

  • EMI mitigation of GaN power inverter leg by local shielding techniques
    • Paweł Derkacz
    • Jean-Luc Schanen
    • Pierre-Olivier Jeannin
    • Piotr Chrzan
    • Piotr Musznicki
    • Mickael Petit
    2022 IEEE TRANSACTIONS ON POWER ELECTRONICS

    This paper presents local shielding techniques applied to a half-bridge inverter leg with the aim to reduce the common mode (CM) current noise at converter’s DC input. The research study is conducted for 650V Enhancement mode Gallium Nitride (GaN) power transistor switches. Main contributors of parasitic capacitances referred to the inverter-leg middle point node are identified. Then, shielding solutions are proposed to reduce CM current emission by these capacitances. Respecting the precautions concerning the isolation of CM currents of the half-bridge inverter leg, the electromagnetic compatibility measurement setup is developed. Experimental step-by-step addition of local shielding copper layers to different contributors of middle point capacitance shows progressive attenuation of CM noise spectra.

  • Emission Profiles of Volatiles during 3D Printing with ABS, ASA, Nylon, and PETG Polymer Filaments
    • Wojciech Wojnowski
    • Mariusz Marć
    • Kaja Kalinowska
    • Paulina Kosmela
    • Bożena Zabiegała
    2022 Pełny tekst MOLECULES

    In this short communication we characterize the emission of volatile organic compounds (VOCs) from fused filament fabrication (FFF) 3D printing using four polymer materials, namely polyethylene terephthalate glycol-modified (PETG), acrylonitrile styrene acrylate (ASA), Nylon, and acrylonitrile butadiene styrene (ABS). Detailed emission profiles are obtained during thermal degradation of the polymers as a function of temperature and also in real-time during 3D printing. Direct quantitative measurement was performed using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS). Qualitative determination of the volatiles emitted from the printed elements at various temperatures was accomplished using gas chromatography-mass spectrometry (GC-MS). The emission rates of VOCs differ significantly between the different polymer filaments, with the emission from Nylon and PETG more than an order of magnitude lower than that of ABS.

  • Emotion Recognition from Physiological Channels Using Graph Neural Network
    • Tomasz Wierciński
    • Mateusz Rock
    • Robert Zwierzycki
    • Teresa Zawadzka
    • Michał Zawadzki
    2022 Pełny tekst SENSORS

    In recent years, a number of new research papers have emerged on the application of neural networks in affective computing. One of the newest trends observed is the utilization of graph neural networks (GNNs) to recognize emotions. The study presented in the paper follows this trend. Within the work, GraphSleepNet (a GNN for classifying the stages of sleep) was adjusted for emotion recognition and validated for this purpose. The key assumption of the validation was to analyze its correctness for the Circumplex model to further analyze the solution for emotion recognition in the Ekman modal. The novelty of this research is not only the utilization of a GNN network with GraphSleepNet architecture for emotion recognition, but also the analysis of the potential of emotion recognition based on differential entropy features in the Ekman model with a neutral state and a special focus on continuous emotion recognition during the performance of an activity The GNN was validated against the AMIGOS dataset. The research shows how the use of various modalities influences the correctness of the recognition of basic emotions and the neutral state. Moreover, the correctness of the recognition of basic emotions is validated for two configurations of the GNN. The results show numerous interesting observations for Ekman’s model while the accuracy of the Circumplex model is similar to the baseline methods.

  • Empirical Analysis of Forest Penalizing Attribute and Its Enhanced Variations for Android Malware Detection
    • Abimbola G. Akintola
    • Abdullateef O. Balogun
    • Luiz Fernando Capretz
    • Hammed Mojeed
    • Shuib Basri
    • Shakirat A. Salihu
    • Fatima E. Usman-Hamza
    • Peter O. Sadiku
    • Ghaniyyat B. Balogun
    • Zubair O. Alanamu
    2022 Pełny tekst Applied Sciences-Basel

    As a result of the rapid advancement of mobile and internet technology, a plethora of new mobile security risks has recently emerged. Many techniques have been developed to address the risks associated with Android malware. The most extensively used method for identifying Android malware is signature-based detection. The drawback of this method, however, is that it is unable to detect unknown malware. As a consequence of this problem, machine learning (ML) methods for detecting and classifying malware applications were developed. The goal of conventional ML approaches is to improve classification accuracy. However, owing to imbalanced real-world datasets, the traditional classification algorithms perform poorly in detecting malicious apps. As a result, in this study, we developed a meta-learning approach based on the forest penalizing attribute (FPA) classification algorithm for detecting malware applications. In other words, with this research, we investigated how to improve Android malware detection by applying empirical analysis of FPA and its enhanced variants (Cas_FPA and RoF_FPA). The proposed FPA and its enhanced variants were tested using the Malgenome and Drebin Android malware datasets, which contain features gathered from both static and dynamic Android malware analysis. Furthermore, the findings obtained using the proposed technique were compared with baseline classifiers and existing malware detection methods to validate their effectiveness in detecting malware application families. Based on the findings, FPA outperforms the baseline classifiers and existing ML-based Android malware detection models in dealing with the unbalanced family categorization of Android malware apps, with an accuracy of 98.94% and an area under curve (AUC) value of 0.999. Hence, further development and deployment of FPA-based meta-learners for Android malware detection and other cybersecurity threats is recommended.

  • End-of-life management of single-use baby diapers: Analysis of technical, health and environment aspects
    • Justyna Płotka-Wasylka
    • Patrycja Makoś-Chełstowska
    • Aleksandra Kurowska-Susdorf
    • María José Santoyo Treviño
    • Sergio Zarazúa Guzmán
    • Heba Mostafa
    • Mauro Cordella
    2022 Pełny tekst SCIENCE OF THE TOTAL ENVIRONMENT

    Single-use baby diapers belongs to an important group of products used in the parenting journey because of their high performance and convenience. Single-use baby diapers are normally thrown away after one-time use, resulting in a waste management problem. The goal of this paper was to better understand main environmental concerns of different types of diapers and address how to reduce them, with a special consideration of waste management strategies and user behaviour practices. Furthermore, health and environmental hazards potentially associated with materials included in diapers, or substances formed from diapers during the waste treatment stage, are also analysed (e.g., phthalates, pesticides, dioxins, pesticides). Three main types of baby diapers have been analysed: single-use baby diapers, reusable baby diapers, and biodegradable single-use diapers. Each type of diaper comes with technical characteristics and environmental concerns and challenges, which are discussed in this paper to support the development of measures for the safe(r) and sustainable design, use and end of life management of baby diapers.

  • .Energia a rozwój gospodarki
    • Waldemar Kamrat
    2022

    Przedstawiono uwarunkowania rozwoju gospodarki krajowej vs rozwój sektora energii. Wskazano na koniecznosc transformacji energetycznej

  • ENERGY AND EMISSION QUALITY RANKING OF NEWLY PRODUCED LOW-SULPHUR MARINE FUEL
    • Zbigniew Korczewski
    2022 Pełny tekst Polish Maritime Research

    The article describes the methodology of engine tests on new types of low-sulphur marine fuels in laboratory conditions in order to conduct a comprehensive assessment of their suitability for powering full-size marine engines. The innovativeness of the proposed solution consists of adapting the laboratory Diesel Engine Test Bed to carry out experimental tests using residual and alternative fuels so that it is possible to imitate the real operating conditions of the ship engine. The main aim of the research program was to assess the energy efficiency of six different low-sulphur marine fuels and their impact on the chemical emissivity of engine exhaust gases and air pollution with toxic and harmful chemical compounds. In order to achieve the research purpose formulated in this way, it was necessary to: (1) equip the constructed laboratory stand with highly specialised measuring equipment and (2) develop a technology for determining diagnostic parameters representing the basis for developing a ranking of the energy and emission quality of the tested marine fuels according to the proposed physical model. The model distinguishes 10 diagnostic parameters that, after normalisation, form two subsets of evaluation parameters - stimulant and destimulant. Determining their values made it possible to estimate a synthetic variable, according to which all the tested fuels were adjusted in the order from the “best” to the “worst”, in accordance with the adopted qualitative criteria of such an assessment. The results of the laboratory tests show that among the considered fuels, i.e., MDO, MGO, RMD 80/L, RMD 80/S, RME 180, and RMG 380 type, the best solution is to use MDO distillate fuel to power full-size marine engines. However, taking into account its high purchase price, a rational alternative decision is to choose RMG 380 type residual fuel, which ranks second in the ranking of the functional quality of the tested marine fuels.

  • Energy and valuable organic products recovery from anaerobic processes
    • Ewa Zaborowska
    • Mojtaba Maktabifard
    • Xiang Li
    • Xianbao Xu
    • Jacek Mąkinia
    2022

    Chapter 8 contains: Introduction, Energy balance in wastewater treatment plants and potential energy recovery, Potential valuable products recovery, Anaerobic processes focused on liquid products recovery; Anaerobic digestion (AD) processes focused on gaseous products recovery, Processes enhancing energy and valuable organic products recovery, Conclusions and perspectives. Anaerobic processes offer different pathways for the recovery of a wide variety of valuable products, both in liquid and gaseous form. These processes can be directed through the appropriate selection of substrates and methods of their pretreatment, process conditions and upgrading in order to obtain valuable products of the expected quality. Both well-established and emerging technologies can be applied and combined to implement the principles of circular economy and sustainability in wastewater treatment and organic waste management. In response to scientific achievements and technological development, promoted and stimulated by global trends, policies and favorable economic conditions, wastewater treatment plants are gradually transforming into water resource recovery facilities.

  • Energy Management for PV Powered Hybrid Storage System in Electric Vehicles Using Artificial Neural Network and Aquila Optimizer Algorithm
    • Namala Narasimhulu
    • R. S. R. Krishnam Naidu
    • Przemysław Falkowski-Gilski
    • Parameshachari Bidare Divakarachari
    • Upendra Roy
    2022 Pełny tekst ENERGIES

    In an electric vehicle (EV), using more than one energy source often provides a safe ride without concerns about range. EVs are powered by photovoltaic (PV), battery, and ultracapacitor (UC) systems. The overall results of this arrangement are an increase in travel distance; a reduction in battery size; improved reaction, especially under overload; and an extension of battery life. Improved results allow the energy to be used efficiently, provide a comfortable ride, and require fewer energy sources. In this research, energy management between the PV system and the hybrid energy storage system (HESS), including the battery, and UC are discussed. The energy management control algorithms called Artificial Neural Network (ANN) and Aquila Optimizer Algorithm (AOA) are proposed. The proposed combined ANN–AOA approach takes full advantage of UC while limiting the battery discharge current, since it also mitigates high-speed dynamic battery charging and discharging currents. The responses’ behaviors are depicted and viewed in the MATLAB simulation environment to represent load variations and various road conditions. We also discuss the management among the PV system, battery, and UC to achieve the higher speed of 91 km/h when compared with existing Modified Harmony Search (MHS) and Genetic Algorithm-based Proportional Integral Derivative (GA-PID). The outcomes of this study could aid researchers and professionals from the automotive industry as well as various third parties involved in designing, maintaining, and evaluating a variety of energy sources and storage systems, especially renewable ones.

  • Energy Security of Polish Consumers in 2004-2021
    • Krystyna Gomółka
    • Piotr Kasprzak
    2022 Pełny tekst Annales Universitatis Mariae Curie-Skłodowska, Sectio H Oeconomia

    Theoretical background: Energy security is one of the most important components of economic security. It is influenced not only by access to energy sources and the economic situation of the state and the individual consumer. The authors adopted the definition of energy security of an individual consumer as included in the UN report. It states that energy security of an individual consumer is guaranteed when the average consumer has access to energy at all times, in various forms, in sufficient quantity and at a reasonable price, with the simultaneous development of support mechanisms for socially and economically sensitive consumers, and after implementation of independent mechanisms for resolving disputes with the energy company, which eliminate or at least alleviate the economic advantage of the enterprises

  • Engineering and Management of Space Systems (EMSS) - an international joint Master's double-degree program
    • Jasminka Matevska
    • Justyna Szostak
    • Zbigniew Łubniewski
    • Szymon Krawczuk
    • Marek Chodnicki
    2022 Pełny tekst

    Dynamic development of the space sector of European, and especially of Polish and German economies results in a necessity for suitable Higher Education Institution graduates. The increasing digitization, distribution and networking of technical systems leads to the necessity of a degree programme teaching “the systems view” and “interdisciplinarity” methods and skills. Furthermore, it is necessary to consider the entire life cycle of the systems starting with the analysis of the requirements, through design, integration, verification, to operation and maintenance, with supplementation of management, social and intercultural skills. Since interdisciplinarity and internationality are essential for engineering and management of space systems, the international project was launched early last year by two universities – Hochschule Bremen (Bremen City University of Applied Sciences, HSB, Germany) and Politechnika Gdańska (Gdańsk University of Technology, Gdańsk Tech, Poland) establishing an international interdisciplinary joint Master's double-degree program - Engineering and Management of Space Systems (EMSS). It consists of three different fixed three- or four-semester study paths of several mobility schemes, though individual educational pathways adjusted to students' preference are also allowed. Each path includesa joint academic year – first semester is conducted in Gdańsk, the second in Bremen. The remaining semesters can be studied at either of the universities. All of the EMSS curricula meet the highest education standards of both countries. Several mandatory modules and many elective courses are included in the EMSS curricula. Upon graduation, students of the program are awarded two Master’s degrees - in Space and Satellite Technologies, issued by Gdańsk Tech, and, depending on the chosen study path, in Aerospace Technologies, Computer Science, or Electronics Engineering issued by HSB. Work on the establishment of a new, international, joint field of study - Engineering and Management of Space Systems, run by both universities is currently in progress. The curriculum of the new study programme will be based on the recommendations of the International Council On Systems Engineering (INCOSE) and its German Chapter, Gesellschaft für Systems Engineering (GfSE), and will offer the possibility of certification as a Systems Engineering Professional, Associate Level. This paper includes the lecturers’ and students’ perspective

  • Enhanced aging resistance of poly(ε-caprolactone)/brewers’ spent grain composites
    • Aleksander Hejna
    • Krzysztof Formela
    • Mateusz Barczewski
    • Tairong Kuang
    • Mohammad Saeb
    2022 Pełny tekst Polimery

    The presented paper investigated the influence of brewers’ spent grain (BSG) extrusion pa-rameters on the photo-oxidative resistance of poly(ε-caprolactone)-based wood polymer composites. Filler samples characterized by the higher melanoidin content were more efficient in hindering of poly-mer degradation, inhibiting the decomposition of the polymer amorphous phase. As aresult, deteriora-tion of mechanical performance was limited, which was expressed by the higher values of aging factor for samples containing BSG extruded at higher temperatures.

  • Enhanced solar light photocatalytic performance of Fe-ZnO in the presence of H2O2, S2O82−, and HSO5− for degradation of chlorpyrifos from agricultural wastes: Toxicities investigation
    • Noor S. Shah
    • Jibran Iqbal
    • Murtaza Sayed
    • Ayman A. Ghfar
    • Javed Ali Khan
    • Zia Ul Haq Khan
    • Behzad Murtaza
    • Grzegorz Boczkaj
    • Farrukh Jamil
    2022 CHEMOSPHERE

    This study reported Fe doped zinc oxide (Fe-ZnO) synthesis to degrade chlorpyrifos (CPY), a highly toxic organophosphate pesticide and important sources of agricultural wastes. Fourier transform infrared, X-ray diffraction, scanning electron microscope, and energy-dispersive X-ray spectroscopic analyses showed successful formation of the Fe-ZnO with highly crystalline and amorphous nature. Water collected from agricultural wastes were treated with Fe-ZnO and the results showed 67% degradation of CPY by Fe-ZnO versus 39% by ZnO at 140 min treatment time. Detail mechanism involving reactive oxygen species production from solar light activated Fe-ZnO and their role in degradation of CPY was assessed. Use of H2O2, peroxydisulfate (S2O82−) and peroxymonosulfate (HSO5−) with Fe-ZnO under solar irradiation promoted removal of CPY. The peroxides yielded hydroxyl (radical dotOH) and sulfate radical (Image 1) under solar irradiation mediated by Fe-ZnO. Effects of several parameters including concentration of pollutant and oxidants, pH, co-existing ions, and presence of natural organic matter on CPY degradation were studied. Among peroxides, HSO5− revealed to provide better performance. The prepared Fe-ZnO showed high reusability and greater mineralization of CPY. The GC-MS analysis showed degradation of CPY resulted into several transformation products (TPs). Toxicity analysis of CPY as well as its TPs was performed and the formation of non-toxic acetate imply greater capability of the treatment technology.

  • Enhanced stability of electrochemical performance of few-layer black phosphorus electrodes by noncovalent adsorption of 1,4-diamine-9,10-anthraquinone
    • Paweł Jakóbczyk
    • Anna Dettlaff
    • Grzegorz Skowierzak
    • Tadeusz Ossowski
    • Jacek Ryl
    • Robert Bogdanowicz
    2022 Pełny tekst ELECTROCHIMICA ACTA

    In this paper, the novel noncovalent functionalisation strategy of few-layer black phosphorus by 1,4-diamine-9,10-anthraquinone electrode was proposed and studied. The degradation of few-layer black phosphorus under exposure to oxygen and water is a significant obstacle to its use as an electroanalytical electrode. The anthraquinone compound adsorbed at black phosphorus flakes results in improved prevention of the phosphorus surface against degradation and electrode decomposition. Furthermore, a large concentration of amino group present in 1,4-diamine-9,10-anthraquinone enhances the electrochemical performance of electrode revealed by a faster rate of heterogeneous electron transfer observed in cyclic voltammetry studies. The designed electrode exhibits stable redox peaks over 100 cycles with separation between the peaks of 79 ± 2 mV and the formal redox potential reaching 257 ± 3 mV. The differential pulse voltammetry was utilised for the detection of ascorbic acid, revealing a limit of detection equal to 3.29 ppm (18.68 µM) and a limit of quantification of 9.98 ppm (56.66 µM). The linear range of 1–20 ppm was achieved, allowing for the detection of ascorbic acid in real conditions. Thus, anthraquinone-modified few-layer black phosphorus may be an attractive novel electrode material for sensitive electroanalytical applications.

  • Enhanced susceptibility of SARS-CoV-2 spike RBD protein assay targeted by cellular receptors ACE2 and CD147: Multivariate data analysis of multisine impedimetric response
    • Mateusz Brodowski
    • Mattia Pierpaoli
    • Monika Janik
    • Marcin Kowalski
    • Mateusz Ficek
    • Paweł Ślepski
    • Bartosz Trzaskowski
    • Greg N. Swain
    • Jacek Ryl
    • Robert Bogdanowicz
    2022 Pełny tekst SENSORS AND ACTUATORS B-CHEMICAL

    Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enters the cells through the binding of spike protein to the host cell surface-expressing angiotensin-converting enzyme 2 (ACE2) or by endocytosis mediated by extracellular matrix metalloproteinase inducer (CD147). We present extended statistical studies of the multisine dynamic electrochemical impedance spectroscopy (DEIS) revealing interactions between Spike RBD and cellular receptors ACE2 and CD147, and a reference anti-RBD antibody (IgG2B) based on a functionalised boron-doped diamond (BDD) electrode. The DEIS was supported by a multivariate data analysis of a SARS-CoV-2 Spike RBD assay and cross-correlated with the atomic-level information revealed by molecular dynamics simulations. This approach allowed us to study and detect subtle changes in the electrical properties responsible for the susceptibility of cellular receptors to SARS-CoV-2, revealing their interactions. Changes in electrical homogeneity in the function of the RBD concentration led to the conclusion that the ACE2 receptor delivers the most homogeneous surface, delivered by the high electrostatic potential of the relevant docking regions. For higher RBD concentrations, the differences in electrical homogeneity between electrodes with different receptors vanish. Collectively, this study reveals interdependent virus entry pathways involving separately ACE2, CD147, and spike protein, as assessed using a biosensing platform for the rapid screening of cellular interactions (i.e. testing various mutations of SARS-CoV-2 or screening of therapeutic drugs).

  • Enhanced Toxicity of Bisphenols Together with UV Filters in Water: Identification of Synergy and Antagonism in Three-Component Mixtures
    • Błażej Kudłak
    • Natalia Jatkowska
    • Wen Liu
    • Michael Williams
    • Damia Barcelo
    • Helgi B. Schiöth
    2022 Pełny tekst MOLECULES

    Contaminants of emerging concern (CEC) localize in the biome in variable combinations of complex mixtures that are often environmentally persistent, bioaccumulate and biomagnify, prompting a need for extensive monitoring. Many cosmetics include UV filters that are listed as CECs, such as benzophenone derivatives (oxybenzone, OXYB), cinnamates (2-ethylhexyl 4-methoxycinnamate, EMC) and camphor derivatives (4-methylbenzylidene-camphor, 4MBC). Furthermore, in numerous water sources, these UV filters have been detected together with Bisphenols (BPs), which are commonly used in plastics and can be physiologically detrimental. We utilized bioluminescent bacteria (Microtox assay) to monitor these CEC mixtures at environmentally relevant doses, and performed the first systematic study involving three sunscreen components (OXYB, 4MBC and EMC) and three BPs (BPA, BPS or BPF). Moreover, a breast cell line and cell viability assay were employed to determine the possible effect of these mixtures on human cells. Toxicity modeling, with concentration addition (CA) and independent action (IA) approaches, was performed, followed by data interpretation using Model Deviation Ratio (MDR) evaluation.

  • Enhancing Customer Engagement in Social Media with AI – a Higher Education case study
    • Edyta Gołąb-Andrzejak
    2022 Pełny tekst

    Purpose. The study aims to demonstrate the importance of artificial intelligence (AI) and examples of tools based on it in the process of enhancing (building, measuring, and managing) customer engagement (CE) in social media in the higher education industry. CE is one of the current essential non-financial indicators of company performance in Digital Marketing strategy. The article presents a decision support system (DSS) based on social media engagement management with the use of AI-based tools in a higher education industry case study. Methodology. The study was based on an analysis of the literature on AI in conjunction with CE, the results of research – 2022 Social Media Industry Benchmark – prepared by Rival IQ, and qualitative research (in-depth interviews with experts) at selected universities in Poland. At a later stage, the interviews were transcribed, thematically analyzed, and open coding with NVivo was performed. Findings. The conducted study was of an introductory and exploratory nature. It recognises the significant role of AI in enhancing CE in social media. At the same time, examples of AI-based tools that can be used for this have been indicated. It was unequivocally stated that by implementing AI in marketing, universities can act more effectively and consequently enhance their non-financial performance. For them, it is a system that assists decision-making in the field of social media engagement management. Research limitations. Due to its preliminary nature, the study used secondary sources (Rival IQ Report 2022) and individual indepth interviews with three managers of promotion/marketing departments, which does not give a complete picture of the situation under analysis. However, it is the first step in research on this subject that is to be continued. The theoretical contribution. The conducted research demonstrated the role of AI in enhancing customer engagement in social media in higher education while at the same time showing its auxiliary role in the decision-making process. Practical implications. Specific tools such as Sprout Social or Rival IQ were identified that, when applied in universities, can measure the engagement rate and effective CE management in social media used by the university.