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Repozytorium publikacji
Politechniki Gdańskiej

Publikacje z roku 2024

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  • Optimizing Control of Wastewater Treatment Plant With Reinforcement Learning: Technical Evaluation of Twin-Delayed Deep Deterministic Policy Gradient Agent
    • Zuzanna Klawikowska
    • Michał Grochowski
    2024 IEEE Access

    Control of the wastewater treatment processes presents significant challenges due to the fluctuating nature of inflow and wastewater composition, alongside the system’s non-linear dynamics. Traditional control methods struggle to adapt to these variations, leading to an economically suboptimal operation of the process and a violation of norms imposed on the quality of wastewater discharged to the catchment area. This study proposes using a reinforcement learning approach to control a wastewater treatment plant. Specifically, the twin-delayed deep deterministic policy gradient algorithm is employed and comprehensively validated. This algorithm enhances control efficiency, optimizing costs while improving the plant’s wastewater treatment capabilities. The proposed control approach is implemented and evaluated using Benchmark Simulation Model No. 1. The evaluation is based on four representative weather scenarios and examines sixteen different metrics. In the proposed case study, an agent controls oxygen transfer coefficients in three oxygen tanks of a wastewater treatment plant. Two distinct reward functions are employed to guide the reinforcement learning agent. The first one focuses on maintaining aerobic conditions and minimizing total nitrogen. The second function retains these objectives and also aims to minimize the aeration energy. The experimental results demonstrate that the proposed control strategy significantly enhances aeration energy efficiency and reduces the overall cost index, indicating a more cost-effective operation. However, future work is required to improve further the performance of reinforcement learning that optimizes the wastewater treatment process.


  • Optimizing Ni–Cr patterned boron-doped diamond band electrodes: Doping effects on electrochemical efficiency and posaconazole sensing performance
    • Anna Dettlaff
    • Michał Rycewicz
    • Łukasz Macewicz
    • Paweł Rutecki
    • Mirosław Sawczak
    • Paul Wittendorp
    • Shruti Jain
    • Elizaveta Vereshchagina
    • Robert Bogdanowicz
    2024 TALANTA.The International Journal of Pure and Applied Analytical Chemistry

    There is growing interest in developing diamond electrodes with defined geometries such as, for example, micrometer-sized electrode arrays to acquire signals for electroanalysis. For electroanalytical sensing applications, it is essential to achieve precise conductive patterns on the insulating surface. This work provides a novel approach to boron-doped diamond patterning using nichrome masking for selective seeding on an oxidized silicon substrate. The optimized process involves nichrome deposition, sonication, chemical etching, seeding, and tailored chemical vapor deposition of boron-doped diamond with an intrinsic layer to suppress boron diffusion. Through a systematic investigation, it was determined that isolated boron-doped diamond band electrodes can be efficiently produced on non-conductive silica. Additionally, the influence of boron doping on electrochemical performance was studied, with higher doping enhancing the electrochemical response of band electrodes. To demonstrate sensing capabilities, boron-doped diamond bands were used to detect posaconazole, an antifungal drug, exploiting its electroactive behaviour. A linear correlation between posaconazole concentration and oxidation peak current was observed over 1.43 × 10−8 – 5.71 × 10−6 M with a 1.4 × 10−8 M detection limit. The developed boron-doped diamond microbands could significantly impact the field of electroanalysis, facilitating detection of diverse biologically relevant molecules. Overall, this diamond patterning approach overcomes major challenges towards all-diamond electrochemical sensor chips.


  • Optymalizacja izolatora przepustowego średniego napięcia do zastosowań technologicznych
    • Paweł Pankowski
    • Marek Olesz
    2024 Pełny tekst Przegląd Elektrotechniczny

    W publikacji podjęto się rozpoznania przyczyn uszkodzeń izolatora przepustowego średniego napięcia (SN) stosowanego w procesie technologicznym oczyszczania ropy naftowej. Z uwagi na skomplikowany model izolatora wykonano obliczenia symulacyjne w układzie 2D na podstawie których wyznaczono charakterystyki natężenia pola elektrycznego. W obszarach wtrącin powietrznych lub nieprawidłowo dobranej izolacji promieniowej wartości natężenia pola silnie wzrastają powodując wyładowania niezupełne przyspieszające starzenie układu izolacyjnego.


  • Organic pollutants photodegradation increment with use of TiO2 nanotubes decorated with transition metals after pulsed laser treatment
    • Zuzanna Bielan
    • Adam Kubiak
    • Jakub Karczewski
    • Jacek Ryl
    • Karol Załęski
    • Emerson Coy
    • Piotr Krawczyk
    • Katarzyna Siuzdak
    2024 MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING

    Among various titanium(IV) oxide (TiO2, titania) structures, 1D nanotubes (TiO2 NTs) produced during the two-electrode anodization process, are extensively utilized in sensors or supercapacitors as well as in photo(electro)catalytic water splitting. However, due to wide bandgap and fast electron-hole recombination additional modifications, mostly concerned on materials surface, are required. According to the recent research, TiO2 NTs photo(electro)catalytic characteristic were markedly improved by the combination of surface decoration with transition metal nanoparticles further treated with the laser beam. Nevertheless, until recently, the photocatalytic ability of laser-treated TiO2 NTs for recalcitrant chemicals degradation were hardly described. In this regard, our work focuses on obtaining long, about 7.3 μm TiO2 NTs (L-TiO2 NTs), together with their photoactivity and physicochemical characteristics, as well as their alterations following surface modification utilizing transition metals (tungsten, chromium and nickel) together with laser treatment. Obtained L-TiO2 NTs are characterized by over 13.5 times larger BET surface area in comparison to reference spaced TiO2 NTs with approximately 2 μm length (0.61 m2 g−1 and 0.05 m2 g−1, respectively). This allowed for increasing of the materials photocatalytic activity in both UV–vis and vis light. Additionally, phenol photodegradation reached up to 34% (0.21·10−2 min−1) for tungsten-modified titania after laser annealing at 20 mJ cm2 fluence. The reaction mechanism research revealed that reduction of organic pollutants concentration was primarily caused by superoxide radical anions •O2−. Furthermore, obtained modified L-TiO2 NTs showed remarkable durability without losing their initial activity over ten photocatalytic cycles.


  • Organizational ethics and position relationship moderators among knowledge workers: a regional study of Poland
    • Jolanta Kowal
    • Anna Jasińska-Biliczak
    • Paweł Weichbroth
    2024 Information Technology for Development

    This research explores organizational ethics among knowledge workers using ICT4Ds in regional enterprises in Poland before, during, and after the COVID-19 pandemic. The study addresses the importance of understanding how ethics in organizations, particularly ethical optimism, corporate social responsibility, and top management action, have evolved across these periods. This topic is crucial as organizational ethics influence employee behavior and decision-making, particularly during crises. The research question focuses on how organizational ethics, influenced by gender and the pandemic, differ by position. Online surveys and random sampling were employed to collect data among knowledge workers (139 before, 134 during, and 98 after the pandemic). The study applied multivariate statistical methods, including variance analysis and causal moderation. Findings were that superiors rated organizational ethics higher than subordinates, and ethical optimism fluctuated, rising during the pandemic and dropping afterward. The study contributes to understanding the role of gender and crises as moderators in organizational ethics, benefiting managers and policymakers.


  • Organizational Resilience in Hospitality and Tourism
    • Małgorzata Rozkwitalska-Welenc
    • Jacek Borzyszkowski,
    • Beata Basińska
    • Fevzi Okumus
    • Osman M. Karatepe
    2024

    Although ‘VUCA’ is not a new term, the features of the world it describes, a volatile, uncertain, complex and ambiguous environment, have never been more valid. The VUCA world has become the new reality for business, specifically for hospitality and tourism organizations that are more vulnerable than any other sector due to the historically-recognized turbulent environment in which they operate. In this book, the authors present unique factors that make hospitality and tourism organizations resilient in the VUCA world. With contacts at the center of their hospitality and tourism organizational resilience model, the organizational and psychological perspectives are also incorporated. This innovative volume tests the model of organizational resilience in hospitality and tourism organizations. The study identifies and validates organizational and individual factors that create a resilient organization in the hospitality and tourism sector. It will be of interest to researchers, academics, practitioners, and advanced students in the fields of organizational studies, strategic management, hospitality, and tourism management.


  • Orientation effects on the fracture behaviour of additively manufactured stainless steel 316L subjected to high cyclic fatigue
    • Mateusz Kopec
    • Gunputh Urvashi
    • Wojciech Macek
    • Zbigniew Kowalewski
    • Paul Wood
    2024 THEORETICAL AND APPLIED FRACTURE MECHANICS

    In this paper, stainless steel 316L (SS316L) bars were additively manufactured (AM) in three orientations (Z – vertical, XY – horizontal, ZX45 – midway between vertical and horizontal) by using the Laser Powder Bed Fusion Melting (LPBF-M) method. The AM specimens were subjected to load control fatigue testing under full tension and compression (R = -1) at stress amplitudes ±350, ±400 and ±450 MPa. The XY and ZX45 printing orientations were found to significantly improve service life. Although similar strain response was found for each orientation when the same stress amplitude was applied, slightly different fracture mechanisms were identified during the post-mortem surface observations.


  • Origami Antennas for Wireless Communication Systems
    • Syed Imran Hussain Shah
    • Shahid Bashir
    • Sławomir Kozieł
    2024

    This book discusses the lightweight, reconfigurable, and deployable origami antennas for adaptive communication systems. Traditional antennas, with their fixed characteristics, struggle to meet the evolving needs of modern communication systems. Reconfigurable antennas, on the other hand, can dynamically adjust their operating parameters, offering significant advantages in terms of performance, size, and cost. Origami technology has emerged as a disruptive force in antenna design, enabling the development of lightweight, reconfigurable antennas with tailored radiation characteristics. Deployable origami antennas offer a transformative solution for applications demanding mobility and rapid deployment in challenging environments. These innovative antennas hold immense promise to revolutionize communication systems, paving the way for a future where adaptability and versatility are paramount. This book offers a comprehensive guide to origami antenna technology, encompassing both fundamentals and practical applications. It might be a valuable resource for researchers and engineers working in the field of antenna development, particularly those focused on wireless communication systems with reconfigurability and deployability are essential design prerequisites.


  • OrphaGPT: An Adapted Large Language Model for Orphan Diseases Classification
    • Kushal Pokhrel
    • Cesar Sanin
    • Md Rafiqul Islam
    • Edward Szczerbicki
    2024

    Orphan diseases (OD) represent a category of rare conditions that affect only a relatively small number of individuals. These conditions are often neglected in research due to the challenges posed by their scarcity, making medical advancements difficult. Then, the ever-evolving medical research and diagnosis landscape calls for more attention and innovative approaches to address the complex challenges of rare diseases and OD. Pre-trained LLMs are a crucial component of contemporary artificial intelligence (AI), contributing to significant advancements in the performance of complex AI tasks. In this research, we aim to introduce a novel model that leverages the capabilities of a fine-tuned GPT-3.5 Turbo model with reasonable accuracy. We design a comprehensive, customized user interface named OrphaGPT, an interactive GPT chat that allows users to engage in deeper conversations about ODs. Our model achieves an 80% accuracy rate, attained through an exploration of Natural Language Processing (NLP), and domain-specific fine-tuning and fine-prompting. Our findings provide valuable insights into the new perspectives of prompting as a way of fine-tuning LLMs while customizing them to specialised domains. This showcases the potential for adaptive generative AI to play a pivotal role in the specific field of OD. The implications of this research extend to medical practitioners, researchers, and the OD community, offering new interactive ways to understand, identify, and diagnose such complex diseases through the customized advanced language model. The successful customization of LLMs into specific fields signifies an advancement of AI, contextualising dialogues and presenting implications for future advances.


  • „Osiem kobiet”, ogólnopolska wystawa malarstwa, grafiki i rzeźby, Muzeum Śremskie.
    • Dominika Krechowicz
    2024

    „Osiem kobiet”, ogólnopolska wystawa malarstwa, grafiki i rzeźby, Muzeum Śremskie. W wystawie biorą udział: Dominika Krechowicz, Jowita Mormul, Paulina Komorowska-Birger, Monika Korona, Joanna Trzcińska, Katarzyna Słuchocka, Joanna Stefańska, Natalia Wegner. Kuratorstwo wystawy: Katarzyna Słuchocka, Joanna Stefańska, Instytut Architektury Wnętrz i Wzornictwa Przemysłowego, Wydział Architektury Politechniki Poznańskiej


  • Otwarte zasoby edukacyjne w codziennych zadaniach pracownika biblioteki publicznej – wyniki ankiety
    • Kamila Kokot-Kanikuła
    • Alicja Toboła-Rynkiewicz
    2024 Pełny tekst

    Artykuł prezentuje wyniki ankiety przeprowadzonej przez pracowników Biblioteki Politechniki Gdańskiej wśród pracowników bibliotek publicznych w Gdańsku i Gdyni na temat wykorzystania otwartych zasobów edukacyjnych w ich codziennej pracy. Celem badania było określenie stopnia znajomości otwartych zasobów edukacyjnych oraz zaproponowanie ewentualnej oferty szkoleniowej na ten temat. Ankieta była przeprowadzona w formie online za pomocą formularza Google w okresie od listopada 2021 do lutego 2022 r. Spośród 50 osób biorących udział w badaniu, 37 zadeklarowało, że zetknęło się z otwartymi zasobami edukacyjnymi, co daje 74%. Natomiast niska frekwencja wśród respondentów (na 319 zaproszonych wpłynęło 50 odpowiedzi) spowodowała, że przeprowadzający ankietę zrezygnowali z organizacji szkoleń.


  • Overcoming Phobias: Harnessing the Power of Immersive Virtual Reality Therapy
    • Agnieszka Popławska
    • Jacek Lebiedź
    • Przemysław Bąbel
    2024

    The goal of the chapter was to review the different therapeutic techniques used in the treatment of various forms of phobias, with particular emphasis on virtual reality treatment. We define different types of phobias, including social ones. We also describe treatment techniques – adopted from behavioral therapy – which have been developed to aid the treatment of phobias. Particular emphasis has been placed on the flooding, implosive therapy and systematic desensitization. We review the results of virtual reality treatment, which show that one of the most effective and most emotionally engaging techniques is that known as Cave Automatic Virtual Environment CAVE – literally a room which one enters and is automatically completely immersed in a virtual reality. In this context, a description of the possibilities on offer at the Immersive 3D Visualization Lab built on the premise of Gdańsk University of Technology, is a substantial and significant part of the chapter. The laboratory, which, unlike any other such laboratory in the world, features a spherical walk simulator, offers people the possibility to move around the CAVE while they are completely immersed in 3D virtual reality. We also present a few applications which make use of virtual reality and have been developed to serve as therapeutic tools in the treatment of phobias. Thus, our chapter combines a narrative review of the literature with a detailed description and discussion of the technical and practical issues in applying CAVE in the treatment of phobias.


  • Own or public? Later livelihoods of Ukrainian war migrant households in Poland
    • Katarzyna Kochaniak
    • Anna M. Korzeniowska
    • Michał Pietrzak
    2024 Pełny tekst INTERNATIONAL MIGRATION

    This paper presents empirical research on the livelihood resources of Ukrainian households that fled to Poland due to the Russian invasion and reside there long term. Using a nationwide sample of these households and an accurate econometric framework, we investigate the factors influencing the role of income from work, other private resources and public assistance in covering their living costs in exile. Our findings confirm the importance of public assistance addressed to professional activation and childcare for households' self-reliance. Assistance from employers, housing conditions, intentions to settle permanently in Poland and financial responsibility for relatives in Ukraine are also among the decisive factors. However, sufficient monetary aid hinders households' self-reliance, along with health problems, language barriers and a lack of professional qualifications. Household composition is also significant, as those with children face the most adverse outcomes. Based on our results, we provide recommendations for public authorities responsible for migration policy.


  • Oxidation kinetics and electrical properties of oxide scales formed under exposure to air and Ar–H2-H2O atmospheres on the Crofer 22 H ferritic steel for high-temperature applications such as interconnects in solid oxide cell stacks
    • Tomasz Brylewski
    • Sebastian Molin
    • M Stygar
    • Maciej Bik
    • Piotr Jeleń
    • Maciej Sitarz
    • Aleksander Gil
    • Ming Chen
    • Peter Vang Hendriksen
    2024 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    A 100 h isothermal oxidation kinetics study for Crofer 22H was conducted in air and the Ar–H2-H2O gas mixture (p(H2)/p(H2O) = 94/6) in the range of 973–1123 K. The parabolic rate constant was independent of oxygen partial pressure in the range from 6.2 × 10−24 to 0.21 atm at 1023 and 1073 K, while at 973 and 1123 K it was higher in air than in Ar–H2-H2O. The scales consisted of Cr2O3 and manganese chromium spinel with an Mn:Cr ratio dependent on the oxidation conditions. Cross-scale resistance was evaluated with regards to the application of the steel in solid oxide fuel cells using a number of methods, including X-ray diffraction, scanning electron microscopy, confocal Raman imaging and area-specific resistance measurements.


  • Oxolane Ammonium Salts (Muscarine-Like)—Synthesis and Microbiological Activity
    • Patrycja Bogdanowicz
    • Janusz Madaj
    • Piotr Szweda
    • Artur Sikorski
    • Justyna Samaszko-Fiertek
    • Barbara Dmochowska
    2024 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Commercially available 2-deoxy-D-ribose was used to synthesize the appropriate oxolane derivative—(2R,3S)-2-(hydroxymethyl)oxolan-3-ol—by reduction and dehydration/cyclization in an acidic aqueous solution. Its monotosyl derivative, as a result of the quaternization reaction, allowed us to obtain eight new muscarine-type derivatives containing a quaternary nitrogen atom and a hydroxyl group linked to the oxolane ring. Their structure was fully confirmed by the results of NMR, MS and IR analyses. The crystal structure of the pyridinium derivative showed a high similarity of the conformation of the oxolane ring to previously published crystal structures of muscarine. Two reference strains of Gram-negative bacteria (Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853), two reference strains of Gram-positive staphylococci (Staphylococcus aureus ATCC 25923 and Staphylococcus aureus ATCC 29213) and four reference strains of pathogenic yeasts of the genus Candida spp. (Candida albicans SC5314, Candida glabrata DSM 11226, Candida krusei DSM 6128 and Candida parapsilosis DSM 5784) were selected for the evaluation of the antimicrobial potential of the synthesized compounds. The derivative containing the longest (decyl) chain attached to the quaternary nitrogen atom turned out to be the most active.


  • Oxygen concentration regulated the efficient liquefaction of vulcanized natural rubber
    • Teng Ren
    • Xinyan Yue
    • Xiaorong He
    • Krzysztof Formela
    • Shifeng Wang
    2024 POLYMER DEGRADATION AND STABILITY

    Oxidative liquefaction represents a promising avenue for the homogeneous and high-value utilization of waste tire rubber. Given that truck tires predominantly comprise natural rubber (NR), this study investigated the efficient liquefaction of vulcanized NR regulated by oxygen concentration. Remarkably, the liquefaction of vulcanized NR was realized with an oxygen concentration of 75 % at 200 °C within 3 min. FTIR spectroscopy showed that carbonyl, ether and sulphoxide groups were produced during the liquification of NR vulcanizates. Oxygen concentration significantly affected the oxidative efficiency of both the main chains and crosslinks, with a more pronounced effect observed on the main chains. Nevertheless, the similar molecular weights and polydispersity indices across various degraded products suggested a selective oxidative cleavage of the NR backbone. Furthermore, online ATR-FTIR was used to monitor the dynamic changes of NR's molecular structure to elucidate the oxidative degradation mechanism. The oxidative cleavage of NR main chain primarily occurred at the C-C bonds connected with allyl groups, producing oxidized products enriched with conjugated carbonyl groups. Alternatively, the main chain scission may also occur due to the electronic rearrangement effect of the C=C bond and produce saturated carbonyl groups. Oxygen concentration modulated the degradation efficiency of vulcanized NR, which provided an efficient strategy for the upcycling of NR-based waste tires.


  • Oxylipin profiling for clinical research: Current status and future perspectives
    • Karol Parchem
    • Sophia Letsiou
    • Toni Petan
    • Olga Oskolkova
    • Isabel Medina
    • Ondrej Kuda
    • Valerie B. O'Donnell
    • Anna Nicolaou
    • Maria Fedorova
    • Valery Bochkov
    • Cécile Gladine
    2024 Pełny tekst PROGRESS IN LIPID RESEARCH

    Oxylipins are potent lipid mediators with increasing interest in clinical research. They are usually measured in systemic circulation and can provide a wealth of information regarding key biological processes such as inflammation, vascular tone, or blood coagulation. Although procedures still require harmonization to generate comparable oxylipin datasets, performing comprehensive profiling of circulating oxylipins in large studies is feasible and no longer restricted by technical barriers. However, it is essential to improve and facilitate the biological interpretation of complex oxylipin profiles to truly leverage their potential in clinical research. This requires regular updating of our knowledge about the metabolism and the mode of action of oxylipins, and consideration of all factors that may influence circulating oxylipin profiles independently of the studied disease or condition. This review aims to provide the readers with updated and necessary information regarding oxylipin metabolism, their different forms in systemic circulation, the current limitations in deducing oxylipin cellular effects from in vitro bioactivity studies, the biological and technical confounding factors needed to consider for a proper interpretation of oxylipin profiles.


  • Ozone nanobubble technology as a novel AOPs for pollutants degradation under high salinity conditions
    • Priya Koundle
    • Neelkanth Nirmalkar
    • Malwina Momotko
    • Grzegorz Boczkaj
    2024 WATER RESEARCH

    Conventional water treatment systems frequently exhibit diminished efficiency at high salinity - a significant issue especially for real industrial effluents - mostly due to the creation of intricate structures between pollutants and salts. One of the primary obstacles associated with high salinity conditions is the generation of by-products that pose additional hurdles for treatment. In this work, we have investigated the novel advanced oxidation process a so-called ozone nanobubble technology for degradation of the pollutants at high salinity conditions. The mass transfer is often the rate-limiting step in gas-liquid process and the poor rate of mass transfer diminishes the overall efficacy. One of the primary disadvantages associated with ozone is its restricted solubility and instability when dissolved in an aqueous solution. These characteristics impose limitations on its potential applications and need the use of specialized systems to facilitate gas-liquid interaction. In this work, we have also suggested enhancing the ozonation process through the utilization of ozone nanobubbles. The findings of our experiment and subsequent analysis indicate that the presence of nanobubbles enhances the process of ozonation through three key mechanisms: (i) an increased mass transfer coefficient, (ii) a higher rate of reactive oxygen species (ROS) generation attributed to the charged interface, and (iii) the nanobubble interface serving as an active surface for chemical reactions. The predicted mass transfer coefficients were found to range from 3 to 3.5 min−1, a value that is notably greater than that seen for microbubbles. The study showcased the degradation of methylene blue dye through the utilization of ozone nanobubbles, which exhibited a much higher rate of dye degradation compared to ozone microbubbles. The confirmation of the radical degradation mechanism was achieved by the utilization of electron spin resonance (ESR) measurements. The developed process has high potential for application in industrial scale textile wastewater treatment.


  • Packing Incubation and Addition of Rot Fungi Extracts Improve BTEX Elimination from Air in Biotrickling Filters
    • Piotr Rybarczyk
    • Krzysztof Cichon
    • Karolina Kucharska
    • Dominik Dobrzyniewski
    • Bartosz Szulczyński
    • Jacek Gębicki
    2024 MOLECULES

    The removal of benzene, toluene, ethylbenzene, and xylene (BTEX) from air was investigated in two similar biotrickling filters (BTFs) packed with polyurethane (PU) foam, differing in terms of inoculation procedure (BTF A was packed with pre-incubated PU discs, and BTF B was inoculated via the continuous recirculation of a liquid inoculum). The effects of white rot fungi enzyme extract addition and system responses to variable VOC loading, liquid trickling patterns, and pH were studied. Positive effects of both packing incubation and enzyme addition on biotrickling filtration performance were identified. BFF A exhibited a shorter start-up period (approximately 20 days) and lower pressure drop (75 ± 6 mm H2O) than BTF B (30 days; 86 ± 5 mm H2O), indicating the superior effects of packing incubation over inoculum circulation during the biotrickling filter start-up. The novel approach of using white rot fungi extracts resulted in fast system recovery and enhanced process performance after the BTF acidification episode. Average BTEX elimination capacities of 28.8 ± 0.4 g/(m3 h) and 23.1 ± 0.4 g/(m3 h) were reached for BTF A and BTF B, respectively. This study presents new strategies for controlling and improving the abatement of BTEX in biotrickling filters.


  • Paid work activity and entrepreneurial cognitions of students – evidence from European emerging economies
    • Liubov Halkiv
    • Paweł Ziemiański
    2024 Pełny tekst Journal of Entrepreneurship in Emerging Economies

    Purpose – This paper aims to investigate whether paid work activity (PWA) experience of students from five emerging economies is related to academic results and self-assessment of possessed entrepreneurial traits. Additionally, the authors verify the relationship between obtaining work experience and the willingness to start own business among students. Design/methodology/approach – Participants included 3,631 students of the first level of higher education at six universities in five countries (Bulgaria, Latvia, Lithuania, Poland and Ukraine). A survey questionnaire was used which included questions on the previous work experience, paid work during university studies, the assessment of competencies related to entrepreneurship and the assessment of the desirability of entrepreneurship as a career choice. Findings – Findings indicate that students who engaged in PWA before studies are more likely to do it during studies.PWAduring studies is related to perceiving oneself as a worse-performing student, but also to the perception of oneself as an entrepreneurial person. No such relationship was found for the PWA experience before entering the university. Itwas also found that students are likely to start their businesses after obtaining work experience. Practical implications – Practical implications pertain to the role of the contemporary academic institutions that should consider their approach to enabling students’ PWA and teaching them how to engage in it for the benefit of their own and the societies to which they belong. It is argued that it may be particularly essential in emerging economies. Originality/value – The correlates of PWA of students have been underexplored. This paper allows broadening the current understanding of this phenomenon. The authors investigated its relationship with feeling entrepreneurial and academic achievements among young people from five emerging economies, which provides valuable insights for policymakers and educational institutions. It is argued that such insights may be particularly essential in emerging economies. Additionally, the authors contribute to advancing two theories that have not been extensively used in the entrepreneurial context: expectancy theory and social learning theory of career development.