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Ostatnie pozycje
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Stymulacyjna funkcja podatku dochodowego
- Piotr Kasprzak
W opracowaniu podjęto próbę opisania i usystematyzowania wiedzy na temat systemu ulg i zwolnień podatkowych stosowanych w Polsce. Autor przedstawia m.in. historię i ewolucję systemu podatkowego w Polsce, począwszy od roku 1989, tłumacząc przy tym rolę państwa. Omówione zostały też trendy i kierunki rozwoju podatków dochodowych. W książce znajdują się informacje na temat istoty i funkcji podatków, ze szczególnym uwzględnieniem stymulacyjnej funkcji podatków. W pracy omówiono również teorię dotyczącą podatków dochodowych od osób fizycznych i prawnych. Autor wymienia i objaśnia stosowane w praktyce ulgi i zwolnienia w podatku dochodowym dla osób fizycznych i prawnych. W opracowaniu przedstawiono analizę pojęć systemu gospodarczego, podatku dochodowego, preferencji podatkowych. Przeprowadzono także analizę sposobów stymulacji zachowań przedsiębiorców w kontekście mechanizmów makroekonomicznych, w tym automatycznych stabilizatorów koniunktury w postaci ulg i zwolnień. Niniejsza książka jest kolejną pozycją, która powstała na podstawie rozprawy doktorskiej autora. Tym razem skupiono się jednak na teoretycznej stronie systemu preferencji podatkowych w systemie gospodarczym.
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Subjective quality evaluation of 8- and 10-bit MP4-coded video sequences from Netflix
- Przemysław Falkowski-Gilski
- Tadeus Uhl
- Parameshachari Bidare Divakarachari
Recently, many researchers have been intensively conducting quality of service (QoS), quality of experience (QoE), and user experience (UX) studies in the field of video analysis. This paper is intended to make a new, complementary contribution to this field. Currently, streaming platforms are key products in relation to delivering video content online. Most often, they include the MP4 video format, which is most widely utilized among audio-visual codecs. This study involves a group of 38 individuals, aged between 21–35 years old, in a laboratory consisting of 20 iMacs with 4K retina display. The presented signal sequences included content sourced from the Netflix Chimera repository, with 8- and 10-bit depth, available in different resolutions of 270p, 432p, 720p, and 1080p. Tests included a subjective quality evaluation in a 5-step mean opinion score (MOS) scale, focused on the UX aspect. According to the obtained results, content with the lowest and highest resolutions is optimal in 8-bit depth, while movies with intermediate resolutions are better in 10-bit depth. For 8-bit content, the main problem is pixelation, whereas, in the case of 10-bit samples, the main issue is color noise, particularly in the case of the lowest resolution. Many viewers indicated that 10-bit encoding offered lower quality. Moreover, 8-bit movies caused a lower quality of the gradient, presumably due to the smaller range of the available color. However, 8-bit movies in the same situation generate visible stripes on static images in the background, causing a lower quality of the gradient, which is probably due to the smaller range of available colors. The results of the performed experiments may be of particular interest to content creators and distributors, particularly network and cable operators, as well as wireless and wired providers.
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Sub‐Nanometer‐Scale Cu9S5 Enables Efficiently Electrochemical Nitrate Reduction to Ammonia
- Chao Feng
- Hanyang Wu
- Jiaxin Shao
- Qihua Huo
- Afaq Hassan
- Hengpan Yang
- Qi Hu
- Chuanxin He
The sub-nanometer is a key feature size in materials science. Unlike single-atom and nanomaterials, size effects and inter-component cooperative actions in sub-nanomaterials will effective on its performance is more significant. Here, 0.95 nm ordered arrangement Cu9S5 sub-nanowires (Cu9S5 SNWs) are synthesized through the co-assembly effect of inorganic nuclei (Cu9S5) and clusters (phosphotungstic acid-PTA), achieving a significant increase in the specific surface area of the sample and ≈100% atomic exposure rate, which is the key to its high catalytic activity. PTA clusters not only act as a “charge transfer station” to accelerate the inter-component electron transfer process, but also facilitate the dissociation of water and provide more hydrogen protons, thus dramatically facilitating the electrocatalytic process. The experimental results show that the Cu9S5 SNWs exhibited excellent nitrate reduction reaction (NO3−RR) properties. The Faraday efficiency (FE) of NO3−RR is 90.4% at the optimum potential −0.3 VRHE (reversible hydrogen electrode) and the ammonia production is as high as 0.37 mmol h−1 cm−2, which is superior to most reported electrocatalysts. In addition, the Zn-NO3− liquid-flow battery devices assembled using Cu9S5 SNWs as electrode materials show excellent application results. This work provides a reference for the design of highly efficient sub-nanoscale NO3−RR electrocatalysts.
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Substrate Integrated Waveguide-Based Frequency-Tunable Self-Octaplexing Antenna
- Nrusingha Pradhan
- Sławomir Kozieł
- Karthikeyan Subramanian
This communication presents the first-ever substrate integrated waveguide (SIW)-based frequency-tunable self-octaplexing antenna (SOA) for wireless communication. The structure is arranged by implementing eight distinct patches with planar 50-ohm feedlines at the top of the SIW cavity, which realize eight distinct resonant frequencies. Independent tuning of each resonant frequency is achieved by incorporating appropriately allocated pockets in the antenna substrate, which can be filled with solid dielectrics of dierent permittivity. The obtained tuning range is broad, from 4.76 GHz to 9.82 GHz, with the capability of tuning each port individually. Furthermore, the port isolation (for all ports) that is better than 20.5 dB. The proposed antenna has a realized gain of 3.91, 3.2, 4.05, 4.14, 3.8, 3.37, 3.55 and 3.28 dBi when using Rogers RT-6010 for pocket filling. Furthermore, the antenna provides stable radiation characteristics with precise tuning. The proposed device is suitable for various applications, including multi-standard wireless communications, due to its small size, wide tuning range, consistent radiation patterns, and comparable isolation levels.
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Substrate Integrated Waveguide-Based Ultra-Compact Self-Heptaplexing Antenna for IoT Connectivity
- Nrusingha Pradhan
- Sławomir Kozieł
- Karthikeyan Subramanian
This paper introduces an innovative design of a substrate-integrated waveguide (SIW)-based self-heptaplexing antenna (SHA). The proposed structure is implemented using a combination of circular and rectangular HM-SIW cavities. Furthermore, the antenna contains seven individual patches on top of the SIW cavity to operate at seven distinct frequencies. The microstrip feeding technique has been used to activate seven distinct ports. All patches are excited through 50-ohm feedlines. The antenna operation is elucidated using an equivalent LC model. To demonstrate its operating principles a self-heptaplexing antenna has been designed to work at 2.45, 3, 3.58, 4, 4.45, 5.2, and 5.88 GHz. The measured realized gain of the proposed antenna at the respective bands is 3.2, 3.85, 3.1, 3.245, 4, 2.98, and 4.5 dBi. The isolation exceeds 20 dB over the entire working bands. The EM-simulated and measured characteristics are in good agreement. Although the suggested antenna has been designed for seven ports and lower frequencies, it has a relatively compact size of 0.28 2g. The major advantages of the proposed self-heptaplexing antenna include excellent isolation, an ultra-compact design, and good radiation characteristics. The proposed antenna offers a high degree of flexibility. It allows for independent frequency tuning, which makes it suitable for IoT, wireless communication systems, and diverse sub-6 GHz band applications.
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Suitability of acoustic power amplifiers as power amplifiers in underwater communication systems
- Aleksander Schmidt
- Jan Schmidt
- Iwona Kochańska
The paper presents selected acoustic power amplifiers from among those currently available. The results of a series of measurements characterising the amplifiers are presented. The measured amplitude and phase characteristics as a function of frequency for four selected amplifiers are analysed. The spectra of the output signal in the band from 4 kHz to 30 kHz are presented. The usefulness of the selected amplifiers in an underwater communication system is assessed.
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Superconductivity in Ternary Mg4Pd7As6
- Hanna Świątek
- Sylwia Gutowska
- Michał Winiarski
- Bartłomiej Wiendlocha
- Tomasz Klimczuk
The synthesis and characterization of a new compound Mg4Pd7As6, which is found to be a superconductor with Tc = 5.45 K is reported. Powder X-ray diffraction confirms the U4Re7Si6 structure (space group Im-3m, no. 229) with the lattice parameter a = 8.2572(1) Å. Magnetization, specific heat, and electrical resistivity measurements indicate that it is a moderate-coupling ( = 0.72) type-II superconductor. The electronic and phonon structures are calculated, highlighting the importance of antibonding Pd–As interactions in determining the properties of this material. The calculated electron–phonon coupling parameter = 0.76 agrees very well with the experimental finding, which confirms the conventional pairing mechanism in Mg4Pd7As6 .
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Superconductivity–Electron Count Relationship in Heusler Phases─the Case of LiPd2Si
- Karolina Górnicka
- Xin Gui
- Juan Chamorro
- Tyrel McQueen
- Robert J. Cava
- Tomasz Klimczuk
- Michał Winiarski
We report superconductivity in the full Heusler compound LiPd2Si (space group Fm3̅m, No. 225) at a critical temperature of Tc = 1.3 K and a normalized heat capacity jump at Tc, ΔC/γTc = 1.1. The low-temperature isothermal magnetization curves imply type-I superconductivity, as previously observed in LiPd2Ge. We show, based on density functional theory calculations and using the molecular orbital theory approach, that while LiPd2Si and LiPd2Ge share the Pd cubic cage motif that is found in most of the reported Heusler superconductors, they show distinctive features in the electronic structure. This is due to the fact that Li occupies the site which, in other compounds, is filled with an early transition metal or a rare-earth metal. Thus, while a simple valence electron count–property relationship is useful in predicting and tuning Heusler materials, inclusion of the symmetry of interacting frontier orbitals is also necessary for the best understanding.
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Support Materials of Organic and Inorganic Origin as Platforms for Horseradish Peroxidase Immobilization: Comparison Study for High Stability and Activity Recovery
- Muhammad Bilal
- Oliwia Degorska
- Daria Szada
- Agnieszka Rybarczyk
- Agata Zdarta
- Michał Kaplon
- Jakub Zdarta
- Teofil Jesionowski
In the presented study, a variety of hybrid and single nanomaterials of various origins were tested as novel platforms for horseradish peroxidase immobilization. A thorough characterization was performed to establish the suitability of the support materials for immobilization, as well as the activity and stability retention of the biocatalysts, which were analyzed and discussed. The physicochemical characterization of the obtained systems proved successful enzyme deposition on all the presented materials. The immobilization of horseradish peroxidase on all the tested supports occurred with an efficiency above 70%. However, for multi-walled carbon nanotubes and hybrids made of chitosan, magnetic nanoparticles, and selenium ions, it reached up to 90%. For these materials, the immobilization yield exceeded 80%, resulting in high amounts of immobilized enzymes. The produced system showed the same optimal pH and temperature conditions as free enzymes; however, over a wider range of conditions, the immobilized enzymes showed activity of over 50%. Finally, a reusability study and storage stability tests showed that horseradish peroxidase immobilized on a hybrid made of chitosan, magnetic nanoparticles, and selenium ions retained around 80% of its initial activity after 10 repeated catalytic cycles and after 20 days of storage. Of all the tested materials, the most favorable for immobilization was the above-mentioned chitosan-based hybrid material. The selenium additive present in the discussed material gives it supplementary properties that increase the immobilization yield of the enzyme and improve enzyme stability. The obtained results confirm the applicability of these nanomaterials as useful platforms for enzyme immobilization in the contemplation of the structural stability of an enzyme and the high catalytic activity of fabricated biocatalysts.
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Supramolecular deep eutectic solvents in extraction processes: a review
- Patrycja Makoś-Chełstowska
- Edyta Słupek
- Sophie Fourmentin
- Jacek Gębicki
Solvent selection is essential for industrial and analytical extraction processes to ensure environmental safety and neutrality. Nevertheless, toxic and hazardous solvents are often used, due to their cost-effectiveness and ready availability. In green chemistry, alternative solvents such as supramolecular deep eutectic solvents are gaining attention due to their superior performance compared with traditional non-green solvents in certain applications. Here we review the use of supramolecular deep eutectic solvents as a green solvent for analytical and industrial liquid–liquid extraction processes, with focus on physicochemical properties, extraction conditions, the capacity factor, the enrichment factor, fuel desulfurization, extraction of biological active compounds, lignin valorization, and sample preparation.
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Surface finite viscoelasticity and surface anti-plane waves
- Victor Eremeev
We introduce the surface viscoelasticity under finite deformations. The theory is straightforward generalization of the Gurtin–Murdoch model to materials with fading memory. Surface viscoelasticity may reflect some surface related creep/stress relaxation phenomena observed at small scales. Discussed model could also describe thin inelastic coatings or thin interfacial layers. The constitutive equations for surface stresses are proposed. As an example we discuss propagation shear (anti-plane) waves in media with surface stresses taking into account viscoelastic effects. Here we analysed surface waves in an elastic half-space with viscoelastic coatings. Dispersion relations were derived.
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Surprising Radiolytic Stability of 8‑Thiomethyladenine in an Aqueous Solution
- Magdalena Datta
- Adrian Szczyrba
- Magdalena Zdrowowicz
- Dariusz Wyrzykowski
- Olga Ciupak
- Sebastian Demkowicz
- Farhad Izadi
- Stephan Denifl
- Janusz Rak
8-Thiomethyladenine (ASCH3), a potentially radiosensitizing modified nucleobase, has been synthesized in a reaction between 8-thioadenine and methyl iodide. Despite favorable dissociative electron attachment (DEA) characteristics, the radiolysis of an aqueous solution of ASCH3 with a dose of X-ray amounting to as much as 300 Gy leads to no effects. Nevertheless, crossed electron-molecule beam experiments in the gas phase on ASCH3 confirm the theoretical findings regarding the stability of its radical anion, namely, the most abundant reaction channel is related to the dissociation of the S-CH3 bond in the respective anion. Furthermore, electroninduced degradation of ASCH3 has been observed in aprotic acetonitrile, which is strong evidence for the involvement of proton transfer (PT) in stabilizing the radical anion in an aqueous solution. These findings demonstrate that PT in water can be the main player in deciding the radiosensitizing properties of modified nucleobases/nucleosides.
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Survey of ICT students' views on self-assessment of professional preparation after remote study
- Marta Szczerska
- Michał Tomczak
- Paweł Ziemiański
- Katarzyna Wajszczyk
The contemporary post-pandemic reality is characterised by an undisputable shift toward remote education and work. The aim of this article is to identify the assessment of ICT evaluation of different forms of study, including desktop, remote and hybrid forms; to find out their preferences towards different forms of education and work, and to determine their sense of self-efficacy in terms of professional tasks undertaken after remote education. A survey method was used and the research sample was based on purposive sampling. The results indicate that, although a hybrid environment is preferred in both educational and professional contexts, the challenge remains to optimise this format in order to improve the quality of education. Nevertheless, the surveyed students feel self-efficacious in their professional activities after remote education.
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Suspension and process parameters selection for electrophoretic deposition of Mn–Co spinel coating on steel interconnects
- Omid Ekhlasiosgouei
- Federico Smeacetto
- Sebastian Molin
Metallic interconnect coatings, consisting of MnCo2O4 spinel, were effectively applied to Crofer 22 APU using the electrophoretic deposition (EPD) method in both H2O: ethanol and pure ethanol solvents. The primary goal of this method was to prevent chromium migration, minimize evaporation, and control the oxidation rate. The study aimed to assess the quality, adhesion, and thickness of the Mn–Co coating, with the objective of achieving a consistent and uniform layer. The results indicated a preference for pure ethanol solvent over H2O: ethanol (40:60 %Vol) for Mn–Co particles. Furthermore, the agglomeration of Mn–Co particles was notably lower (approximately 7 times) in ethanol compared to H2O: ethanol. The morphology and surface roughness of the sintered Mn–Co coating on the alloy were examined using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). A uniform and dense coating was successfully attained using pure ethanol solvent at a solid concentration of 10 g/L, with 0.5 g/L of iodine serving as a disperser. The deposition process, carried out at a voltage of 30V for 20 s, resulted in a coating with a thickness of 7.4 ± 0.3 μm and a surface roughness of 0.75 ± 0.5 μm.
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Sustainable chemically modified poly(butylene adipate-co-terephthalate)/thermoplastic starch/poly(ε-caprolactone)/cellulose biocomposites: looking at the bulk through the surface
- Aleksander Hejna
- Mateusz Barczewski
- Paulina Kosmela
- Olga Mysiukiewicz
- Agnieszka Tercjak
- Adam Piasecki
- Mohammad Saeb
- Marek Szostak
Sustainable polymer composites (or biocomposites) based on renewable and green polymers are progressively under development in a technological paradigm shift from “just use more and more” to “convert into value-added products”. Therefore, significant efforts should focus not only on their reduced environmental impact but also on maximizing their performance and broadening their application range. Herein, the bio-based blends based on Mater-Bi bio-plastic and poly(ε-caprolactone), at a weight ratio of 70:30, were developed, followed by the addition of UFC100 cellulose filler to yield sustainable biocomposites. The effects of cellulose chemical modification with three diisocyanates, i.e., hexamethylene diisocyanate (HDI), methylene diphenyl isocyanate (MDI), or toluene diisocyanate (TDI) on the surface properties of biocomposites were evaluated by water contact angle and surface roughness detected by atomic force microscopy (AFM). Biocomposites containing cellulose modified with HDI, MDI, or TDI revealed contact angle values of 93.5°, 97.7°, and 92.4°, respectively, compared to 88.5° for reference blend, indicating an enlarged hydrophobicity window. This action was further confirmed by increased fracture surface roughness and miscibility detected by microscopic observation (scanning electron microscopy (SEM) and AFM). An in-depth oscillatory rheological evaluation has identified MDI, followed by TDI, as the most efficient compatibilizer of the analyzed system. Correspondingly, thermogravimetric analysis and differential scanning calorimetry analyses showed more residue and higher melting temperatures for biocomposites, more promisingly with MDI and TDI modifiers. In conclusion, either incorporation or diisocyanate modification of cellulose affects both surface and bulk properties, providing vital insights into future developments in the field. Proper selection of diisocyanate modifier of cellulose may enable engineering of composites performance.
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Sustainable energy consumption – Empirical evidence of a household in Poland
- Ewelina Sokołowska
- Jerzy Wiśniewski
There is an expected increase in the demand for electricity from households in European countries. The outcome of the growing proportion of renewable energy sources in the energy supply mix should result in improved customer awareness regarding their electricity usage. Additionally, they must assume a more proactive role in overseeing their electricity usage. Innovation and pollution management have become crucial catalysts for promoting sustainable economic development and environmental protection. This is a response to the increasing threats posed by climate change. This study addresses this existing research gap in sustainable energy consumption. The research aims to examine the advantages of replacing traditional sources of heating with renewable ones. The empirical case study of households in Poland serves as an illustration of the theoretical foundation. The purpose of the study entails the construction of a multi-equation econometric model describing the mechanisms of electricity consumption in a specific household. The model hypothesis indicates that the model should take the form of a system of interdependent equations. The following will be described: the monthly volume of electricity consumption, the cost of this energy payment (in PLN), and the price per one MWh in a given month. Monthly time series from September 2015 to June 2023 were used. The resulting time series amounted to a count of 94 statistical observations. The results in the form of a multi-level empirical econometric model indicate that the economic, environmental, and social benefits of using renewable sources of heating can make a significant contribution to reducing fossil fuel consumption and CO2 emissions. In the context of growing environmental awareness and the need to reduce greenhouse gas emissions, heat pumps are becoming an increasingly important element in the discussion of the future of heating. Their role in transforming the energy sector in the direction of sustainability is crucial.
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Sustainable Management of Food Wastes Through Cavitation-Assisted Conversion into Value-Added Products
- Zahra Askarniya
- Xun Sun
- Chongqing Wang
- Grzegorz Boczkaj
More than 30% of worldwide food consumption is thrown out as food wastes causing serious environmental, economic, and social problems. Therefore, it is required to develop sustainable food waste management methods leading to an enhancement in social and economic benefits and mitigation of environmental impacts. Anaerobic digestion can be regarded as one of those effective methods that can be employed for the conversion of food waste to value-added products. Food wastes are normally resistant towards hydrolysis (the first stage of anaerobic digestion), leading to a reduction in the formation of desired products. Cavitation is one of the useful pretreatment methods that can mitigate this problem and also increase mass transfer, which is a severe barrier to the reaction producing biodiesel (transesterification), leading to high rates of hydrolysis and transesterification. Cavitation is the formation, growth, and collapse of bubbles formed in the solution. Considering the subsequent effect of the collapse of generated bubbles (ability to disintegrate solid material, turbulence, high temperature and pressure, and radical formation), cavitation can be considered an efficient technique for minimizing the time and optimizing the generation of valuable products from food wastes. This technology can cause microbes to easily access substrates, resulting in an enhancement in microbial growth and the formation of products. Additionally, it can increase mass transfer between reactants, decreasing the time required in transesterification for producing biodiesel.
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Symbolic multibody models for digital-twin applications
- Nicolas Docquier
- Krzysztof Lipiński
- Olivier Lantsoght
- Sebastien Timmermans
- Paul Fisette
Symbolic generation of multibody systems equations of motion appeared in the 1980s. In addition to their computational advantage over their numerical counterparts, symbolic models can be very easily and straightforwardly interfaced with a wide range of software environments and hardware devices. These two features place this approach in a pole position to participate and intervene in the design of digital twins for systems such as vehicles, manipulators, walking robots or haptic devices. In this context, the first goal of this paper is to highlight the interest of symbolically generated multibody models – at the root of the ROBOTRAN program – in the form of a standalone set of equations calculating the dynamic model of multibody systems, for use as a computational component within a Digital-Twin-type process. The next goal is to embed realistic and complex multibody models within processes or devices whose functioning requires a synchronized real-time computation – or analysis – of their motion. An implementation (i) on specific hardware and (ii) on two extremely opposite but revealing applications (namely a railway vehicle and a digital piano) are presented to highlight the usefulness of symbolic models for the development of current and future multibody-based digital twins.
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Synergism of floated paperboard sludge cake /sewage sludge for maximizing biomethane yield and biochar recovery from digestate: A step towards circular economy
- Rania H. Hafez
- Ahmed Tawfik
- Gamal K. Hassan
- Magdy Zahran
- Ahmed A. Younes
- Aleksandra Ziembińska-Buczyńska
- Filip Gamoń
- Mahmoud Nasr
Anaerobic digestion of floated paperboard sludge (PS) cake suffers from volatile fatty acids (VFAs) accumulation, nutrient unbalanced condition, and generation of digestate with a risk of secondary pollution. To overcome these drawbacks, sewage sludge (SS) was added to PS cake for biogas recovery improvement under a co-digestion process followed by the thermal treatment of solid fraction of digestate for biochar production. Batch experimental assays were conducted at different SS:PS mixing ratios of 70:30, 50:50, 30:70, and 20:80 (w/w), and their anaerobic co-digestion performances were compared to the mono-digestion systems at 35±0.2 °C for 45 days. The highest methane yield (MY) of 241.68±14.81 mL/g CODremoved was obtained at the optimum SS:PS ratio of 50:50 (w/w). This experimental condition was accompanied by protein, carbohydrate, and VFA conversion efficiencies of 47.3±3.2%, 46.8±3.2%, and 56.3±3.8%, respectively. The synergistic effect of SS and PS cake encouraged the dominance of Bacteroidota (23.19%), Proteobacteria (49.65%), Patescibacteria (8.12%), and Acidovorax (12.60%) responsible for hydrolyzing the complex organic compounds and converting the VFAs into biomethane. Further, the solid fraction of digestate was subjected to thermal treatment at a temperature of 500 °C for 2.0 h, under an oxygen-limited condition. The obtained biochar had a yield of 0.48 g/g dry digestate, and its oxygen-to-carbon (O/C), carbon-to-nitrogen (C/N), and carbon-to-phosphorous (C/P) ratios were 0.55, 10.23, and 16.42, respectively. A combined anaerobic co-digestion/pyrolysis system (capacity 50 m3/d) was designed based on the COD mass balance experimental data and biogenic CO2 market price of 22 USD/ton. This project could earn profits from biogas (12565 USD/yr), biochar (6641 USD/yr), carbon credit (8014 USD/yr), and COD shadow price (6932 USD/yr). The proposed project could maintain a payback period of 6.60 yr. However, further studies are required to determine the associated life cycle cost model that is useful to validate the batch experiment assumptions.
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Synergistic effects of a swirl generator and MXene/ water nanofluids used in a heat exchanger pipe of a negative CO2 emission gas power plant
- Milad Amiri
- Paweł Ziółkowski
- Dariusz Mikielewicz
focus on optimizing heat exchangers contributes to improved temperature control mechanisms, ensuring the sustainable operation of innovative power plants working towards negative CO2 emissions. In the realm of oxy-combustion within Negative CO2 Emission Power Plants (nCO2PP), the temperature of combustion products surpasses 3000 (K). Addressing this challenge, the imperative arises to reduce these elevated temperatures to a manageable 1100(°C). This critical cooling process is achieved through the injection of water, facilitated by the implementation of heat exchangers. The study delves into the optimization of heat transfer within the heat exchanger pipe, specifically tailored for the context of a Negative CO2 Emission Power Plant. Employing a numerical simulation, the investigation explores the impact of vortex generator geometry, vane angles, single and dual propeller-type swirl generators, and the integration of a novel class of fluid, MXene/water nanofluid. Initially, the study scrutinizes propeller-type geometry at vane angles spanning from 15 to 60 degrees. The enhanced swirl flow associated with lower vane angles leads to improved fluid mixing, fostering more effective heat transfer. Results showed that the 15-degree vane angle, with a wider circumferential coverage, may result in increased wall contact, influencing heat transfer efficiency. Subsequently, at Re=6000, incremental rates of the Nusselt number ((〖Nu〗_n-〖Nu〗_s)/〖Nu〗_s %), for θ=15, 30, 45, and 60 degrees are 175.1%, 108.8%, 90.7%, and 40.3%, respectively. Also, the increment rates of Friction Factor (f_n/f_s ) for aforementioned vane angle are 38.48%, 9.26%, 4.08%, and 2.42%, respectively. In addition, for ∅_MXene=0.5 %, the Nusselt number experiences considerable increments of 22.94%, 24.17%, 24.70%, and 24.707% at Reynolds numbers of 6000, 12000, 18000, and 24000, respectively, compared to pure water, emphasizing the potential of MXene to enhance heat transfer efficiency.
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Synteza i charakterystyka „zielonych” mieszanin polimerowych na bazie biopochodnego termoplastycznego poliuretanu i octanomaślanu celulozy
- Ewa Głowińska
- Joanna Smorawska
- Joanna Niesiobędzka
- Julia Grocholska
- Janusz Datta
Otrzymano mieszaniny polimerowe z biopochodnego termoplastycznego poliuretanu (TPU) i dostępnego handlowo octanomaślanu celulozy (CAB), stosowanego w ilości 0–20%. TPU syntezowano metodą prepolimerową z wykorzystaniem biopoliolu, glikolu 1,3-propylenowego i diizocyjanianu heksametylenu. Materiały poddano analizie pod kątem struktury chemicznej (FTIR), właściwości termicznych (TGA, DSC) i właściwości termomechanicznych (DMTA).
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Synteza małocząsteczkowych pochodnych 2-pirydonu wykazujących właściwości przeciwnowotworowe oraz przeciwbakteryjne
- Małgorzata Ryczkowska
Tematyka i cel badawczy niniejszej rozprawy doktorskiej dotyczy syntezy chemicznej związków heterocyklicznych z grupy 2-pirydonu wykazujących potencjał przeciwbakteryjny oraz przeciwnowotworowy. W części teoretycznej podjęto tematykę znanych fluorochinolonów oraz chinolonów wykazujących aktywność przeciwnowotworową. Dodatkowo przedstawiono nowe metody syntezy chinolonów niewymagające stosowania katalizatorów metali przejściowych oraz opublikowane na przestrzeni ostatnich 15 lat. W części badań własnych przedstawiono syntezę arylokarbamoilowych pochodnych 4-fenylo-5,6,7,8-tetrahydrochinolin-2(1H)-onu oraz badania mające na celu poznanie mechanizmu demetylowania podczas acylowania 2-metoksy-5,6,7,8-tetrahydrochinolin-8-olu izocyjanianami fenylowymi. Przedstawiono w niej również syntezę 4-fenylo-5,6,7,8-tetrahydrochinolin-2(1H)-onów modyfikowanych w pozycji 3 podstawnikami typu benzylowego. Ponadto opisano nową metodę syntezy typu „one-pot” rdzeni 4-fenylo-5,6,7,8-tetrahydrochinolin-2(1H)-onu, zbadano mechanizm powstawania trójcyklicznych pochodnych oraz przedstawiono funkcjonalizację pilicydu grupami o charakterze hydrofilowym. W części eksperymentalnej przedstawiono procedury syntezy oraz analizę spektralną wszystkich otrzymanych związków.
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Synthesis and biological evaluation of novel 3,6- amide and thioamide substituted- 2,3,4,9-tetrahydro-1H-carbazoles for anti-cancer activity
- Alicja Trocka
- Anoop Kallingal
- Natalia Maciejewska
- Narajczyk Magdalena
- Anna Hromova
- Sławomir Makowiec
Herein, we report the synthesis of new compounds with demonstrated anticancer properties based on the 2,3,4,9- tetrahydro-1H-carbazole scaffold. The Fischer indolization method was used to close the heterocyclic motif. The synthesis method’s scope and limitations were thoroughly assessed through a series of experiments. Biological assays revealed that two thioamide compounds exhibited significant anticancer activity against MCF-7, HTC116, and A596 cell lines. Comprehensive in vitro profiling included evaluation of cell cytotoxicity, morphological alterations, colony formation and cell adhesion in 3D cultures, cell cycle analysis, DNA damage induction, impact on mitochondria, and apoptosis. Ex ovo studies further demonstrated these compounds’ potential to inhibit angiogenic processes. Our results indicate that the newly developed compounds activate processes leading to DNA damage and disruption of mitochondrial function.
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Synthesis and characterization of MoS2-carbon based materials for enhanced energy storage applications
- Mariusz Szkoda
- Anna Ilnicka
- Konrad Trzciński
- Zuzanna Zarach
- Daria Roda
- Andrzej Nowak
The article delves into the synthesis and characterization of MoS2-carbon-based materials, holding promise for applications in supercapacitors and ion batteries. The synthesis process entails the preparation of MoS2 and its carbon hybrids through exfoliation, hydrothermal treatment, and subsequent pyrolysis. Various analytical techniques were employed to comprehensively examine the structural, compositional, and morphological properties of the resulting materials. The article explores the electrochemical performance of these electrode materials in supercapacitors and ion batteries (LiB, SiB, KiB). Electrochemical measurements were conducted in aqueous electrolyte for supercapacitors and various aprotic electrolytes for ion batteries. Results highlight the impact of the synthesis process on electrochemical performance, emphasizing factors such as capacitance, rate capability, and charge/discharge cycle performance. Hydrothermally treated MoS2-carbon exhibited a specific capacitance of approximately 150 F g-1 in supercapacitors, attributed to its high surface area and efficient charge storage mechanisms. Additionally, for Li-ion battery materials without hydrothermal treatment showed impressive capacity retention of around 88% after 500 charge-discharge cycles, starting with an initial specific capacity of about 920 mAh/g. Long-term stability was demonstrated in both supercapacitors and lithium-ion batteries, with minimal capacitance degradation even after extensive charge-discharge cycles. This research underscores the potential of MoS2-based materials as effective energy storage solutions.
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Synthesis and physical properties of Sm2PdGe3 in a context of RE2PdGe3 family
- Leszek Litzbarski
- Marcin Łapiński
- Tomasz Klimczuk
- Michał Winiarski
In this study, we present the crystallographic and magnetic characterization of a new intermetallic compound Sm2PdGe3, which was synthetized by a two stage method employing an eutectic alloy. The investigations carried out exhibited, that Sm2PdGe3 crystallize in AlB2-type structure with lattice parameters a = 4.2189(1) Å and c = 4.1031(2) Å. This compound can be classified as a cluster-glass with a spin freezing temperature Tf = 10.5 K. Furthermore, there were carried out the analysis of the role of the rare earth (RE) elements on the structural parameters of RE2PdGe3 and draw a correlation between the RE radius and the unit cell parameters. We show that a deviation from the ideal 1:3 Pd:Ge ratio is necessary to synthesize RE2PdGe3 with smaller RE elements.
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Synthesis and Properties of the Ba2PrWO6 Double Perovskite
- Damian Włodarczyk
- Mikolaj Amilusik
- Katarzyna M. Kosyl
- Maciej Chrunik
- Krystyna Ławniczak-Jabłońska
- Hanka Przybylińska
- Paulina Kosmela
- Michał Strankowski
- Lev-Ivan Bulyk
- Volodymyr Tsiumra
- Rajibul Islam
- Carmine Autieri
- Fei Xue
- Marcin Zając
- Anastasiia Lysak
- Roman Minikayev
- Michal Bockowski
- Andrzej Suchocki
We report details on the synthesis and properties of barium praseodymium tungstate, Ba2PrWO6, a double perovskite that has not been synthesized before. Room-temperature (RT) powder X-ray diffraction identified the most probable space group (SG) as monoclinic I2/m, but it was only slightly distorted from the cubic structure. X-ray photoelectron spectroscopy confirmed that the initial (postsynthesis) material contained praseodymium in both 3+ and 4+ charge states. The former (Pr3+) disappeared after exposure to UV light at RT. Photoluminescence studies of Pr3+ revealed that Ba2PrWO6 is an insulator with a band gap exceeding 4.93 eV. Pressure-dependent Raman spectroscopy excluded the possibility of a phase transition up to 20 GPa; however, measurements between 8 and 873 K signified that there might be a change toward the lower symmetry SG below 200 K. Electron paramagnetic resonance spectra revealed the presence of interstitial oxygen which acts as a deep electron trap.
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Synthesis and Structure of Novel Hybrid Compounds Containing Phthalazin-1(2H)-imine and 4,5-Dihydro-1H-imidazole Cores and Their Sulfonyl Derivatives with Potential Biological Activities
- Łukasz Balewski
- Maria Gdaniec
- Anna Herring
- Christophe Furman
- Alina Ghinet
- Jakub Kokoszka
- Anna Ordyszewska
- Anita Kornicka
A novel hybrid compound—2-(4,5-dihydro-1H-imidazol-2-yl)phthalazin-1(2H)-imine (5) was synthesized and converted into di-substituted sulfonamide derivatives 6a–o and phthalazine ring opening products—hydrazonomethylbenzonitriles 7a–m. The newly prepared compounds were characterized using elemental analyses, IR and NMR spectroscopy, as well as mass spectrometry. Single crystal X-ray diffraction data were collected for the representative compounds 5, 6c, 6e, 7g, and 7k. The antiproliferative activity of compound 5, sulfonyl derivatives 6a–o and benzonitriles 7a–m was evaluated on approximately sixty cell lines within nine tumor-type subpanels, including leukemia, lung, colon, CNS, melanoma, ovarian, renal, prostate, and breast. None of the tested compounds showed any activity against the cancer cell lines used. The antioxidant properties of all compounds were assessed using the DPPH, ABTS, and FRAP radical scavenging methods, as well as the β-carotene bleaching test. Antiradical tests revealed that among the investigated compounds, a moderate ABTS antiradical effect was observed for sulfonamide 6j (IC50 = 52.77 µg/mL). Benzonitrile 7i bearing two chlorine atoms on a phenyl ring system showed activity in a β-carotene bleaching test (IC50 = 86.21 µg/mL). Finally, the interaction AGE/RAGE in the presence of the selected phthalazinimines 6a, 6b, 6g, 6m, and hydrazonomethylbenzonitriles 7a, 7c–g, and 7i–k was determined by ELISA assay. A moderate inhibitory potency toward RAGE was found for hydrazonomethylbenzonitriles—7d with an electron-donating methoxy group (R = 3-CH3O-C6H4) and 7f, 7k with an electron-withdrawing substituent (7f, R = 2-Cl-C6H4; 7k, R = 4-NO2-C6H4).
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Synthesis, characterization and application of cross-linked functional terpolymer through epoxy group as sorbent for extraction of cadmium from waters and foods: Multivariate optimization
- Ersen Yılmaz
- Ali Boztuğ
- Hameed Haq
- Grzegorz Boczkaj
- Nail Altunay
The purpose of this study was to develop a selective sorbent for cadmium ions (Cd(II)) enrichment in orbital shaker assisted solid phase microextraction (OS-SPME) from different aqueous and food samples. A maleic anhydride-styrene-glycidyl methacrylate (MA-St-GMA) terpolymer was synthesized and characterized in detail. Experimental variables of sample preparation step were optimized using a central composite design (CCD). The final determination step was performed using flame atomic absorption spectroscopy (FAAS). The MA-St-GMA sorbent exhibited a high adsorption capacity (195.9 mg g−1) for the Cd(II) ion. The developed method under optimal conditions provides satisfactory performance and a significant improvement compared to other protocols available in the literature. The linear range and detection limit of the method is 0.1–130 ng mL−1 and 0.03 ng mL−1, respectively. The robustness, intraday/interday precision, selectivity, and accuracy of the method were investigated. To further validate the method, a dedicated series of analysis was performed using certified reference materials (CRMs). This part of the study confirmed the applicability of the method for routine analysis. The OS-SPME-FAAS method was validated using water and food samples. Relative standard deviations and recovery for real-world samples were in ranges 1.7–2.2 % and 95.5–98.5 %, respectively. As a result, the MA-St-GMA sorbent showed that it could quantitatively extract Cd(II) ions from aqueous solution.
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Synthesis of Trehalose by the Erythritol-Producing Yeast Yarrowia lipolytica Co-Displaying Maltooligosyltrehalose Synthase and Maltooligosyltrehalose Trehalohydrolase
- Shuo Xu
- Yawen Zou
- Liyun Ji
- Muhammad Bilal
- Hairong Cheng
Industrial trehalose production faces economic challenges with costly enzyme preparations, prompting the exploration of eco-friendly alternatives. Here, we established a coupled functional sugar production line leveraging erythritolproducing cells as an innovative enzyme preparation for trehalose synthesis. The erythritol-producing Yarrowia lipolytica was modified to express a fusion protein consisting of maltooligosyltrehalose synthase and maltooligosyltrehalose trehalohydrolase from Sulfolobus solfataricus ATCC35092. The engineered strain YlxsT08 was used for the simultaneous synthesis of erythritol and the fusion protein. The yield, production, and productivity of erythritol reached 0.55 g/g of glucose, 166.18 g/L, and 1.98 g/(L· h), respectively, in a 5 L bioreactor. The recycled cells (49.77 U/ mg of DCW) exhibited a high catalytic efficiency in the bioconversion of maltodextrin to generate trehalose. The yield, production, and productivity of trehalose reached 0.67 g/g maltodextrin, 134.40 g/L, and 5.60 g/(L·h), respectively, in a 5 L bioreactor. The byproducts were removed by biological purification, and the resulting cells were recycled as catalysts for at least the next 5 rounds of trehalose production. Our novel strategy provides an ecologically sustainable and economically feasible alternative to enzyme combinations in trehalose production, offering a cost-effective and eco-friendly enzyme manufacturing method.
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Synthesis, photophysical characterisation, quantum-chemical study and in vitro antiproliferative activity of cyclometalated Ir(iii) complexes based on 3,5-dimethyl-1-phenyl-1H-pyrazole and N,N-donor ligands
- Joanna Masternak
- Karol Okła
- Adam Kubas
- Jiří Voller
- Karolína Kozlanská
- Małgorzata Zienkiewicz-Machnik
- Agnieszka Gilewska
- Jerzy Sitkowski
- Anna Kamecka
- Katarzyna Kazimierczuk
- Barbara Barszcz
In this paper, we present the synthesis of four new complexes: the dimeric precursor [Ir(dmppz)2(μ-Cl)]2 (1) (Hdmppz – 3,5-dimethyl-1-phenyl-1H-pyrazole) and heteroleptic bis-cyclometalated complexes: [Ir (dmppz)2 (Py2CO)]PF6 · 1 2 CH2 Cl2 (2), [Ir(dmppz)2 (H2biim)]PF6·H 2 O (3), and [Ir(dmppz)2 (PyBIm)]PF 6 (4), with auxiliary N,N-donor ligands: 2-di(pyridyl)ketone (Py2CO), 2,2’-biimidazole (H 2biim) and 2-(2’-pyridyl)ben- zimidazole (PyBIm). In the obtained complexes, SC-X-ray analysis revealed that Ir( III) has an octahedral coordination sphere with chromophores of the type {IrN2 C2Cl2 } (1) or {IrN 4C 2} (2–4). The complexes obtained, which have been fully characterised by physicochemical methods (CHN, TG, FTIR, UV-Vis, PL and 1 H, 13 C, 15 N NMR), were used to continue our studies on the factors influencing the cytotoxic pro- perties of potential chemotherapeutic agents (in vitro). To this end, the following studies are presented: (i) comparative analysis of the effects on the biological properties of N,N-donor ligands and C,N-donor ligands in the studied complexes, (ii) studies of the interactions of the compounds with the selected molecular target: DNA and BSA (UV-Vis, CD and PL methods), (iii) and the reactivity towards redox mole- cules: GSH, NADH (UV-Vis and/or ESI-MS methods), (iv) cytotoxic activity (IC50) of potential chemothera- peutics against MCF-7, K-562 and CCRF-CEM cell lines.
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Synthesis, structure and luminescence properties of borate-bismuth glasses and glass-ceramics doped with rare earth ions
- Karolina Milewska
In a doctoral dissertation, new borate-bismuth glasses and glass-ceramics containing AlF3 and SrF2 were examined as potential hosts for RE3+ ions. Experimental studies were conducted to determine optimal conditions for synthesizing transparent borate-bismuth glasses and glass ceramics, with a focus on analyzing their structure and luminescence properties. The introduction of AlF3 into the glass matrix led to an increase in the luminescence intensity of RE3+ ions in glasses containing 10 mol% AlF3. It was observed that the emitted color could be adjusted by varying the ratios of RE3+ ions. In the study of glass-ceramic systems doped with SrF2, successful crystallization of SrF2 nanocrystals was achieved. Structural modifications of the parental glass, leading to SrF2 nanostructure crystallization, were found to depend strongly on the initial amount of strontium fluoride. An increase in luminescence intensity was observed after annealing in samples containing 20 mol% SrF2. Luminescence lifetimes indicated that some of the Eu3+ ions were located in SrF2 nanocrystals, which was further supported by analysis of Judd–Ofelt parameters and luminescence intensity ratio. The presented results suggest that the proposed glasses and glass ceramics could serve as suitable matrices for optically active RE3+ ions.
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System oceny efektywności użytkowania aparatów słuchowych
- Piotr Szymański
Celem rozprawy jest opracowanie metody oceny efektywności protezowania słuchu przy użyciu aparatów słuchowych, która pozwoli w łatwy sposób poddawać ocenie korzyść z użytkowania protez słuchowych w najbardziej typowych sytuacjach akustycznych. Przedstawiono genezę podjętych badań i na tej podstawie zaproponowano cele i tezy rozprawy doktorskiej. W pracy w pierwszej kolejności zawarto przegląd dotyczący rodzajów ubytku słuchu i jego wpływu na jakość życia, rozwiązania wspomagające osoby z ubytkiem słuchu oraz stosowane metody oceny efektywności użytkowania aparatów słuchowych. Wybrane metody omówiono zgodnie ze stanem wiedzy, ze szczególnym uwzględnieniem kwestionariusza APHAB (Abbreviated Profile of Hearing Aid Benefit), który jest jedną z najważniejszych i najczęściej aktualnie stosowanych metod dopasowania aparatów słuchowych. W celu realizacji badań i zebrania danych przygotowano aplikację internetową, która została wdrożona w około 200 punktach protetycznych. Uzyskane dane poddano analizie statystycznej. Analiza wykorzystująca test MUSHRA (MUltiple Stimuli with Hidden Reference and Anchor) oraz wnioskowanie regułowe oparte na logice rozmytej stała się podstawą modyfikacji zaproponowanego systemu. We wnioskach odniesiono się do tez badawczych, wdrożenia zaproponowanej metody, jak również podano kierunki rozwoju prowadzonych badań.
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System wizyjny dla robota łapiącego piłki
- Bartosz Czaja
- Marek Tatara
- Jan M. Kelner
W niniejszej pracy zaproponowano i przetestowano system wizyjny służący śledzeniu lecącej piłki w celu wypracowania sterowania dla robota wieloosiowego mającego za zadanie złapanie jej. Do detekcji i lokalizacji piłki na obrazie z dwóch, prostopadle ustawionych, kamer zastosowano laplasjan filtru gaussowskiego (LoG) oraz autorski podsystem filtracji rozmytej. Estymację trajektorii lecącej piłki w przestrzeni wykonano w oparciu o metodę najmniejszych kwadratów z wykorzystaniem funkcji liniowej i kwadratowej. Zamieszczono szczegółowy opis proponowanego rozwiązania oraz wyniki przeprowadzonych testów.
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Szlifowanie na docierarkach sposobem zmniejszenia skażenia powierzchni ziarnami ściernymi w obróbce wykończeniowej
- Adam Barylski
W artykule przedstawiono szkodliwość skażenia powierzchni mikroziarnami ściernymi w procesach docierania luźnym ścierniwem żeliwa szarego oraz sferoidalnego. Omówiono technologie szlifowania powierzchni płasko-równoległych z kinematyką docierania obiegowego, jako sposób zmniejszenia skażenia powierzchni ścierniwem po obróbce wykończeniowej.
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Szlifowanie powierzchni płasko-równoległych z kinematyką docierania
- Adam Barylski
Przedstawiono charakterystykę szlifowania powierzchni płasko-równoległych z kinematyką docierania obiegowego. Analizowano obróbkę materiałów konstrukcyjnych na docierarkach dwutarczowych. Porównano warunki i wyniki szlifowania z tradycyjnym docieraniem luźnym ścierniwem. Scharakteryzowano sposób wyrównywania powierzchni roboczych narzędzi oraz omówiono główne zalety szlifowania na docierarkach.
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Tailoring Defects in B, N-Codoped Carbon Nanowalls for Direct Electrochemical Oxidation of Glyphosate and its Metabolites
- Mattia Pierpaoli
- Paweł Jakóbczyk
- Mateusz Ficek
- Bartłomiej Dec
- Jacek Ryl
- Bogdan Rutkowski
- Aneta Lewkowicz
- Robert Bogdanowicz
Tailoring the defects in graphene and its related carbon allotropes has great potential to exploit their enhanced electrochemical properties for energy applications, environmental remediation, and sensing. Vertical graphene, also known as carbon nanowalls (CNWs), exhibits a large surface area, enhanced charge transfer capability, and high defect density, making it suitable for a wide range of emerging applications. However, precise control and tuning of the defect size, position, and density remain challenging; moreover, due to their characteristic labyrinthine morphology, conventional characterization techniques and widely accepted quality indicators fail or need to be reformulated. This study primarily focuses on examining the impact of boron heterodoping and argon plasma treatment on CNW structures, uncovering complex interplays between specific defect-induced three-dimensional nanostructures and electrochemical performance. Moreover, the study introduces the use of defect-rich CNWs as a label-free electrode for directly oxidizing glyphosate (GLY), a common herbicide, and its metabolites (sarcosine and aminomethylphosphonic acid) for the first time. Crucially, we discovered that the presence of specific boron bonds (BC and BN), coupled with the absence of Lewis-base functional groups such as pyridinic-N, is essential for the oxidation of these analytes. Notably, the D+D* second-order combinational Raman modes at ≈2570 cm–1 emerged as a reliable indicator of the analytes’ affinity. Contrary to expectations, the electrochemically active surface area and the presence of oxygen-containing functional groups played a secondary role. Argon-plasma post-treatment was found to adversely affect both the morphology and surface chemistry of CNWs, leading to an increase in sp3-hybridized carbon, the introduction of oxygen, and alterations in the types of nitrogen functional groups. Simulations support that certain defects are functional for GLY rather than AMPA. Sarcosine oxidation is the least affected by defect type.
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Tailoring Physicochemical Properties of V2O5 Nanostructures: Influence of Solvent Type in Sol-Gel Synthesis
- Klaudia Prusik
- Daniel Jaworski
- Justyna Gumieniak
- Agnieszka Kramek
- Kamila Sadowska
- Marta Prześniak-Welenc
The influence of different solvents, including aqueous and nonaqueous types, on the physicochemical properties of V2O5 nanostructures was thoroughly investigated. Various characterization techniques, such as XRD, XPS, FTIR, Raman spectroscopy, UV-vis DRS, SEM, TEM, and BET, were employed to analyze the obtained materials. Additionally, the adsorption properties of the synthesized V2O5 nanostructures for methylene blue were examined, and kinetic parameters of adsorption were calculated. The results demonstrate that the morphology of the obtained crystals can be finely controlled by manipulating water concentration in the solution, showcasing its profound impact on both the structural characteristics and adsorption properties of the nanostructures. Furthermore, the structural changes of the resulting V2O5 material induced by solvents show strong impacts on its photocatalytic properties, making it a promising photocatalyst.
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Tailoring the Transport Layer Interface for Relative Indoor and Outdoor Photovoltaic Performance
- Chia-Feng Li
- Shih-Han Cheng
- Hou-Chin Cha
- Ssu-Yung Chung
- Damian Głowienka
- Chih-Min Chuang
- Yu-Ching Huang
The ability to achieve notable indoor power conversion efficiency (PCE) makes organic photovoltaics (OPV) a potential technology for indoor applications. Currently, ongoing research in indoor OPVs focuses on improving both their indoor PCE and their stability. However, little attention has been given to investigating the fabrication yield of indoor OPVs, a pivotal determinant of their potential commercial viability. In this study, we discovered that despite assessing the PCE of OPVs under indoor and solar illumination conditions using the same devices, the fabrication yields under these distinct light sources vary significantly. Employing diverse analytical measurements, we elucidated the underlying mechanisms contributing to this variance. Our findings suggest that disparities in fabrication yield resulted from the interfacial interactions between the hole transport layer (HTL) and the active layer. Particularly, the interfacial behavior between these layers plays a decisive role in achieving elevated fabrication yields in indoor OPVs. Furthermore, we demonstrate the function of a combination of two HTLs (TAPC/MoO3), which not only enhances the indoor PCE of OPVs but also substantially improves the fabrication yield of indoor OPVs. Our study offers insights and critical guidance for the advancement of indoor OPVs with high fabrication yields.
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Tailor-Made Polysaccharides for Biomedical Applications
- Mohsen Khodadadiyazdi
- Farzad Seidi
- Aleksander Hejna
- Payam Zarrintaj
- Navid Rabiee
- Justyna Kucińska-Lipka
- Mohammad Saeb
- Sidi A. Bencherif
Polysaccharides (PSAs) are carbohydrate-based macromolecules widely used in the biomedical field, either in their pure form or in blends/nanocomposites with other materials. The relationship between structure, properties, and functions has inspired scientists to design multifunctional PSAs for various biomedical applications by incorporating unique molecular structures and targeted bulk properties. Multiple strategies, such as conjugation, grafting, cross-linking, and functionalization, have been explored to control their mechanical properties, electrical conductivity, hydrophilicity, degradability, rheological features, and stimuli-responsiveness. For instance, custom-made PSAs are known for their worldwide biomedical applications in tissue engineering, drug/gene delivery, and regenerative medicine. Furthermore, the remarkable advancements in supramolecular engineering and chemistry have paved the way for mission-oriented biomaterial synthesis and the fabrication of customized biomaterials. These materials can synergistically combine the benefits of biology and chemistry to tackle important biomedical questions. Herein, we categorize and summarize PSAs based on their synthesis methods, and explore the main strategies used to customize their chemical structures. We then highlight various properties of PSAs using practical examples. Lastly, we thoroughly describe the biomedical applications of tailor-made PSAs, along with their current existing challenges and potential future directions.
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Targeting Candida albicans O-acetyl-L-homoserine sulfhydrylase (Met15p) in antifungal treatment
- Aleksandra Kuplińska
- Kamila Rząd
- Joanna Stefaniak-Skorupa
- Katarzyna Kozłowska-Tylingo
- Marek Wojciechowski
- Sławomir Milewski
- Iwona Gabriel
Fungal infections are a serious threat to public health as they are becoming increasingly frequent. A major problem stems also from a rising fungal resistance to currently available antifungal therapies, therefore novel molecular targets are highly desirable. Exploration of enzymes participating in the biosynthesis pathways of essential amino acids such as L-methionine (L-Met) may provide new insights into pharmaceutical development. The MET15 gene from Candida albicans, encoding O- acetyl-L-homoserine sulfhydrylase (Met15p), an enzyme catalyzing the second step in that pathway, was cloned and expressed in two versions: as N and C-terminal oligo-His-tagged fusion proteins. The recombinant enzymes revealed appropriate activity, and catalyzed conversion of O-acetyl-L-homoserine and a sulfide ion to produce L-homocysteine. A new RP-HPLC-DAD method, using the enzymatic reaction product pre-column derivatization with 5,5’-dithio-bis-(2-nitrobenzoic acid) was developed and used by us to determine Met15p activity. Newly synthesized compounds as well as two commercially available exhibited a Met15p inhibitory effect which was related to antifungal activity. Fungal cells’ sensitivity to inhibitors depending on the presence or absence of L-Met in the medium clearly indicated Met15p targeting. Moreover, the synergistic effect of the first methionine biosynthetic enzyme affecting inhibitor and Met15p inhibitors indicate that methionine biosynthesis pathway enzymes are promising molecular targets.
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Targeting shelterin proteins for cancer therapy.
- Wioletta Brankiewicz-Kopcinska
- Anoop Kallingal
- Radosław Krzemieniecki
- Maciej Bagiński
As a global health challenge, cancer prompts continuous exploration for innovative therapies that are also based on new targets. One promising avenue is targeting the shelterin protein complex, a safeguard for telomeres crucial in preventing DNA damage. The role of shelterin in modulating ataxia- telangiectasia mutated (ATM) and ataxia-telangiectasia and Rad3-related (ATR) kinases, key players in the DNA damage response (DDR), establishes its significance in cancer cells. Disrupting these defence mechanisms of shelterins, especially in cancer cells, renders telomeres vulnerable, potentially leading to genomic instability and hindering cancer cell survival. In this review, we outline recent approaches exploring shelterins as potential anticancer targets, highlighting the prospect of developing selective molecules to exploit telomere vulnerabilities toward new innovative cancer treatments.
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Targeting yeast topoisomerase II by imidazo and triazoloacridinone derivatives resulting in their antifungal activity
- Kamila Rząd
- Iwona Gabriel
- Ewa Paluszkiewicz
- Aleksandra Kuplińska
- Mateusz Olszewski
- Agnieszka Chylewska
- Aleksandra M. Dąbrowska
- Katarzyna Kozłowska-Tylingo
Fungal pathogens are considered as serious factors for deadly diseases and are a case of medical concern. Invasive fungal infections also complicate the clinical course of COVID-19, leading to a significant increase in mortality. Furthermore, fungal strains' multidrug resistance has increased the demand for antifungals with a different mechanism of action. The present study aimed to identify antifungal compounds targeting yeast topoisomerase II (yTOPOII) derived from well-known human topoisomerase II (hTOPOII) poisons C-1305 and C-1311. Two sets of derivatives: triazoloacridinones (IKE1-8) and imidazoacridinones (IKE9-14) were synthetized and evaluated with a specific emphasis on the molecular mechanism of action. Our results indicated that their effectiveness as enzyme inhibitors was not solely due to intercalation ability but also as a result of influence on catalytic activity by the formation of covalent complexes between plasmid DNA and yTOPOII. Lysine conjunction increased the strength of the compound's interaction with DNA and improved penetration into the fungal cells. Triazoloacridinone derivatives in contrast to starting compound C-1305 exhibited moderate antifungal activity and at least twice lower cytotoxicity. Importantly, compounds (IKE5-8) were not substrates for multidrug ABC transporters whereas a derivative conjugated with lysine (IKE7), showed the ability to overcome C. glabrata fluconazole-resistance (MIC 32–64 µg mL−1).
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Task-recency bias strikes back: Adapting covariances in Exemplar-Free Class Incremental Learning
- Grzegorz Rypeść
- Sebastian Cygert
- Tomasz Trzciński
- Bartłomiej Twardowski
Exemplar-Free Class Incremental Learning (EFCIL) tackles the problem of training a model on a sequence of tasks without access to past data. Existing state-of-the-art methods represent classes as Gaussian distributions in the feature extractor's latent space, enabling Bayes classification or training the classifier by replaying pseudo features. However, we identify two critical issues that compromise their efficacy when the feature extractor is updated on incremental tasks. First, they do not consider that classes' covariance matrices change and must be adapted after each task. Second, they are susceptible to a task-recency bias caused by dimensionality collapse occurring during training. In this work, we propose AdaGauss - a novel method that adapts covariance matrices from task to task and mitigates the task-recency bias owing to the additional anti-collapse loss function. AdaGauss yields state-of-the-art results on popular EFCIL benchmarks and datasets when training from scratch or starting from a pre-trained backbone.
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Teaching High–performance Computing Systems – A Case Study with Parallel Programming APIs: MPI, OpenMP and CUDA
- Paweł Czarnul
- Mariusz Matuszek
- Adam Krzywaniak
High performance computing (HPC) education has become essential in recent years, especially that parallel computing on high performance computing systems enables modern machine learning models to grow in scale. This significant increase in the computational power of modern supercomputers relies on a large number of cores in modern CPUs and GPUs. As a consequence, parallel program development based on parallel thinking has become a necessity to fully utilize modern HPC systems' computational power. Therefore, teaching HPC has become essential in developing skills required by the industry. In this paper we share our experience of conducting a dedicated HPC course, provide a brief description of the course content, and propose a way to conduct HPC laboratory classes, in which a single task is implemented using several APIs, i.e., MPI, OpenMP, CUDA, hybrid MPI+Pthreads, and MPI+OpenMP. Based on the actual task of verifying Goldbach's conjecture for a given range of numbers, we present and analyze the performance evaluation of students' solutions and code speed-ups for MPI and OpenMP. Additionally, we evaluate students' subjective assessment of ease of use of particular APIs along with the lengths of codes, and students' performance over recent years.
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Teaching of Robot Arm Programming - Tasks with Increasing Difficulty
- Marek Chodnicki
- Alina Guzik
- Marek Galewski
- Wiktor Sieklicki
- Michał Mazur
The article describes education techniques using robotics. For example, educational exercises on programming the Nachi MZ04 robotic arm are presented. The exercises use a wooden railroad toy model and elements printed in additive manufacturing technology. The exercises have increasing difficulty and can be used to educate young people in high school and specialized higher engineering studies (both bachelor's and master's).
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Team research project – evolution from faculty activity to university study standard
- Mariusz Kaczmarek
- Krzysztof Nowicki
The article will describe the idea of a university-wide team student project as a tool of modern academic teaching in the era of widespread use of artificial intelligence tools. The problem of contemporary teaching is the emerging tools for automatic content generation, including didactic and scientific content. The question arises how to verify students' qualifications and learning outcomes. The solution may be students' group work on an interdisciplinary problem and a comprehensive approach to solving it. The article will present the current experience of the Faculty of Electronics, Telecommunications and Computer Science in the implementation of student group and research projects and the assumptions of changes in the study programs at the Gdańsk University of Technology (GUT) introducing a university-wide student team research project during master's studies.
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Techno-economic analysis of a hybrid energy system for electrification using an off-grid solar/biogas/battery system employing HOMER: A case study in Vietnam
- Van Bac Nguyen
- Prabhakar Sharma
- Bhaskor Jyoti Bora
- Thi Minh Tu Bui
- Cristina Efremov
- Minh Ho Tran
- Jerzy Kowalski
- Sameh M. Osman
- Dao Nam Cao
- Van Huong Dong
The electrification of off-grid /island villages is a critical step towards improving the techno-economic circumstances of rural regions and the overall general growth of the country. However, consistent supply from a single source is not possible in these areas. Thus, a hybrid renewable energy system performs better in these conditions. The research challenge now is to identify the optimal combinations of HRES from the available resources in a specific village site that can supply the power demand sustainably and to determine whether this is a cost-effective option. The present work is an endeavour to develop a sustainable and dynamic energy demandsupply model using HOMER Pro energy software in a specified off-grid rural site in Vietnam. The research presents four unique configurations of a combined energy system for Vietnam’s island settlements, incorporating biomass-based biogas facilities, photovoltaic panels, lithium-ion batteries, and converters. Homer Pro was used for optimization and design, focusing on key performance measures such as cost of energy, net present cost, initial cost, operating cost, renewable fraction, and carbon emissions. The best HES system layout includes a 100- kW biomass-based generator, 2.62 kW photovoltaic installation, 10 lithium-ion batteries, and a 6.31 kW converter, producing 100 % renewable energy. The system’s low cost of energy ($0.48), and net present cost ($25,730.89) make it an economically viable alternative, while its low CO2 emissions demonstrate its commitment to reducing greenhouse gas emissions.
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Technological solutions to landfill management: Towards recovery of biomethane and carbon neutrality
- Hussein Al-Hazmi
- Gamal K. Hassan
- Tonni Agustiono Kurniawan
- Bogna Śniatała
- Tomy M. Joseph
- Joanna Majtacz
- Grzegorz Piechota
- Xiang Li
- Fatma A. El-Gohary
- Mohammad Saeb
- Jacek Mąkinia
Inadequate landfill management poses risks to the environment and human health, necessitating action. Poorly designed and operated landfills release harmful gases, contaminate water, and deplete resources. Aligning landfill management with the Sustainable Development Goals (SDGs) reveals its crucial role in achieving various targets. Urgent transformation of landfill practices is necessary to address challenges like climate change, carbon neutrality, food security, and resource recovery. The scientific community recognizes landfill management's impact on climate change, evidenced by in over 191 published articles (1998–2023). This article presents emerging solutions for sustainable landfill management, including physico-chemical, oxidation, and biological treatments. Each technology is evaluated for practical applications. The article emphasizes landfill management's global significance in pursuing carbon neutrality, prioritizing resource recovery over end-of-pipe treatments. It is important to note that minimizing water, chemical, and energy inputs in nutrient recovery is crucial for achieving carbon neutrality by 2050. Water reuse, energy recovery, and material selection during manufacturing are vital. The potential of water technologies for recovering macro-nutrients from landfill leachate is explored, considering feasibility factors. Integrated waste management approaches, such as recycling and composting, reduce waste and minimize environmental impact. It is conclusively evident that the water technologies not only facilitate the purification of leachate but also enable the recovery of valuable substances such as ammonium, heavy metals, nutrients, and salts. This recovery process holds economic benefits, while the conversion of CH4 and hydrogen into bioenergy and power generation through microbial fuel cells further enhances its potential. Future research should focus on sustainable and cost-effective treatment technologies for landfill leachate. Improving landfill management can mitigate the adverse environmental and health effects of inadequate waste disposal.
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Temperature Measurements at Tyre Tread Rubber on Sandpaper Oscillatory Sliding Contacts Using Acicular Grindable Thermocouples
- Oleksii Nosko
- Yurii Tsybrii
- Pablo Guillermo Torrelio Arias
- Adolfo Senatore
The tribological performance of tyre–road contacts depends crucially on the contact temperature. This study investigates the reliability and accuracy of acicular grindable thermocouples possessing an original needle-shaped wearable part as applied to measuring temperature at the oscillatory sliding contact between a rubber tyre tread sample and a sandpaper. A linear oscillatory tribometer is used to imitate the sliding phase of tyre–road contact under mild friction conditions. It is shown that the acicular grindable thermocouple measurements are generally test–retest repeatable. Moreover, the thermocouple signal becomes more stable with increasing contact pressure. Compared to the conventional thermocouple technique, the acicular grindable thermocouple overestimates temperature at the rubber friction surface by about 23% due to involvements of its wearable part in friction with the sandpaper. The findings suggest an expansion of the acicular grindable thermocouple technique to full-scale experiments with tyres on the road.
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Teoria grafów wczoraj i dziś
- Marek Kubale
W pracy naszkicowano kamienie milowe teorii grafów poczynając od pierwszego artykułu Eulera na temat mostów w Królewcu z połowy 18. wieku. Następnie opisano słynny problem 4 barw i jego wariacje. Pracę kończy charakterystyka najnowszych wyzwań teorii grafów.