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Publications Repository
Gdańsk University of Technology

Publications from the year 2019

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  • Performance-Based Nested Surrogate Modeling of Antenna Input Characteristics
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    2019 Full text IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION

    Utilization of electromagnetic (EM) simulation tools is mandatory in the design of contemporary antenna structures. At the same time, conducting designs procedures that require multiple evaluations of the antenna at hand, such as parametric optimization or yield-driven design, is hindered by a high cost of accurate EM analysis. To certain extent, this issue can be addressed by utilization of fast replacement models (also referred to as surrogates). Unfortunately, due to curse of dimensionality, traditional data-driven surrogate modeling methods are limited to antenna structures described by a few parameters with relatively narrow parameter ranges. This is by no means sufficient given the complexity of modern designs. In this paper, a novel technique for surrogate modeling of antenna structures is proposed. It involves a construction of two levels of surrogates, both realized as kriging interpolation models. The first model is based on a set of reference designs optimized for selected performance figures. It is used to establish a domain for the final (second-level) surrogate. This formulation permits efficient modeling within wide ranges of antenna geometry parameters and wide ranges of performance figures (e.g., operating frequencies). At the same time, it allows uniform allocation of training data samples in a straightforward manner. Our approach is demonstrated using two microstrip antenna examples and compared to conventional kriging and radial basis function modeling. Application examples for antenna optimization are also provided along with experimental validation.


  • Periodic expansion in determining minimal sets of Lefschetz periods for Morse–Smale diffeomorphisms
    • Grzegorz Graff
    • Małgorzata Lebiedź
    • Adrian Myszkowski
    2019 Full text Journal of Fixed Point Theory and Applications

    We apply the representation of Lefschetz numbers of iterates in the form of periodic expansion to determine the minimal sets of Lefschetz periods of Morse–Smale diffeomorphisms. Applying this approach we present an algorithmic method of finding the family of minimal sets of Lefschetz periods for Ng, a non-orientable compact surfaces without boundary of genus g. We also partially confirm the conjecture of Llibre and Sirvent (J Diff Equ Appl 19(3):402–417, 2013) proving that there are no algebraic obstacles in realizing any set of odd natural numbers as the minimal set of Lefschetz periods on Ng for any g.


  • Periodic Points for Sphere Maps Preserving MonopoleFoliations
    • Grzegorz Graff
    • Michał Misiurewicz
    • Piotr Nowak-Przygodzki
    2019 Full text Qualitative Theory of Dynamical Systems

    Let S^2 be a two-dimensional sphere. We consider two types of its foliations with one singularity and maps f:S^2→S^2 preserving these foliations, more and less regular. We prove that in both cases f has at least |deg(f)| fixed points, where deg(f) is a topological degree of f. In particular, the lower growth rate of the number of fixed points of the iterations of f is at least log|deg(f)|. This confirms the Shub’s conjecture in these classes of maps.


  • Permeability of the small intestinal mucus for physiologically relevant studies: Impact of mucus location and ex vivo treatment
    • Adam Macierzanka
    • Alan Mackie
    • Łukasz Krupa
    2019 Full text Scientific Reports

    The small intestinal mucus is a complex colloidal system that coats the intestinal mucosa. It allows passage on nutrients/pharmaceuticals from the gut lumen towards the epithelium, whilst preventing it from direct contact with luminal microorganisms. Mucus collected from intestinal tissue is often used in studies looking at inter-mucosal transport of food particulates, drug carriers, etc. However, detaching the highly hydrated native mucus from the tissue and storing it frozen prior to use may disrupt its physiological microstructure, and thus selective barrier properties. Multiple-particle tracking experiments showed that microstructural organisation of native, jejunal mucus depends on its spatial location in the intestinal mucosa. The inter-villus mucus was less heterogeneous than the mucus covering villi tips in the pig model used. Collecting mucus from tissue and subjecting it to freezing and thawing did not significantly affect (P > 0.05) its permeability to model, sub-micron sized particles, and the microviscosity profile of the mucus reflected the overall profiles recorded for the native mucus in the tissue. This implies the method of collecting and storing mucus is a reliable ex vivo treatment for the convenient planning and performing of mucus-permeability studies that aim to mimic physiological conditions of the transport of molecules/particles in native mucus.


  • Persistent organic pollutants (POPs) as an indicator of surface water quality in the vicinity of the Polish Polar Station, Horsund
    • Filip Pawlak
    • Krystyna Kozioł
    • Marek Ruman
    • Żaneta Polkowska
    2019 Full text MONATSHEFTE FUR CHEMIE

    Surface waters were collected in the vicinity of the Polish Polar Station in Hornsund (Svalbard) to determine their concentration of various persistent organic pollutants (POPs), such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). In addition, parameters such as pH, SEC and TOC were measured. In total, 15 samples of lake water from and 15 samples of stream water were analysed. The sampling took place between August and September 2010. Total PAHs and PCBs concentrations in surface water ranged from < LOD to 6212 ng/dm3 and < LOD to 273 ng/dm3. Moreover, the main compounds detected in the samples from these two groups were naphthalene and PCB 153. Based on the cluster analysis, it was found that there are no significant differences between the water taken from the lakes and the water taken from the streams.


  • Person Tracking in a Ferry Environment Using Ultra-Wide Band Radio Interface
    • Piotr Rajchowski
    • Krzysztof Cwalina
    • Jarosław Sadowski
    2019

    This article presents research and analysis of effectiveness of tracking moving people in an environment of passenger ferry, using measurements of propagation time of ultra-wide band radio signal (UWB - Ultra-Wide Band). Constructed measurement stand and results of measurements carried out in a real propagation conditions were shortly discussed.


  • Personalized nutrition in ageing society: redox control of major-age related diseases through the NutRedOx Network (COST Action CA16112)
    • Josep Tur
    • Jacob Claus
    • Patrick Chaimbault
    • Mohammad Tadayyon
    • Elke Richling
    • Nina Hermans
    • Claudia Nunes dos Santos
    • Marc Diederich
    • Linda Giblin
    • Mourad Elhabiri
    • Caroline Gaucher
    • Pierre Andreoletti
    • Ana Fernandes
    • Michael Davies
    • Agnieszka Bartoszek-Pączkowska
    • Mustapha Cherkaoui-malki
    2019 Full text FREE RADICAL RESEARCH

    A healthy ageing process is important when it is considered that one-third of the population of Europe is already over 50 years old, although there are regional variations. This proportion is likely to increase in the future, and maintenance of vitality at an older age is not only an important measure of the quality of life but also key to participation and productivity. So, the binomial “nutrition and ageing” has different aspects and poses considerable challenges, providing a fertile ground for research and networks. The NutRedOx network will focus on the impact of redox-active compounds in food on healthy ageing, chemoprevention, and redox control in the context of major age-related diseases. The main aim of the NutRedOx network is to gather experts from Europe, and neighbouring countries, and from different disciplines that are involved in the study of biological redox active food components and are relevant to the ageing organism, its health, function, and vulnerability to dis- ease. Together, these experts will form a major and sustainable EU-wide cluster in form of the NutRedOx Centre of Excellence able to address the topic from different perspectives, with the long- term aim to provide a scientific basis for improved nutritional and lifestyle habits, to train the next generation of multidisciplinary researchers in this field, to raise awareness of such habits among the wider population, and also to engage with industry to develop age-adequate foods and medicines.


  • PG przykładem dobrych praktyk w zakresie Strategii HR4R dla czeskiego uniwersytetu w Zlinie
    • Agnieszka Lendzion
    2019 Full text Pismo PG

    Przedstawiciele czeskiego uniwersytetu w Zlinie (Tomas Bata University, UTB) gościli na Politechnice Gdańskiej w dniach 24–25 września 2019 r. Celem wizyty było poznanie dobrych praktyk PG i wymiana doświadczeń w zakresie wdrażania zasad Europejskiej Karty Naukowca i Kodeksu Postępowania przy Rekrutacji Pracowników Naukowych. Instytut Centrum Systemów Polimerowych UTB uzyskał prawo posługiwania się wyróżnieniem HR na początku 2019 roku, a PG w lipcu 2017 r.


  • Phase I and phase II metabolism simulation of antitumor-active 2-hydroxyacridinone with electrochemistry coupled on-line with mass spectrometry.
    • Agnieszka Potęga
    • Dorota Garwolińska
    • Anna M. Nowicka
    • Michał Fau
    • Agata Kot-Wasik
    • Zofia Mazerska
    2019 Full text XENOBIOTICA

    Here, we report the metabolic profile and the results of associated metabolic studies of 2-hydroxyacridinone (2-OH-AC), the reference compound for antitumor-active imidazo- and triazoloacridinones. Electrochemistry coupled with mass spectrometry was applied to simulate the general oxidative metabolism of 2-OH-AC for the first time. The reactivity of 2-OH-AC products to biomolecules was also examined. The usefulness of the electrochemistry for studying the reactive drug metabolite trapping (conjugation reactions) was evaluated by the comparison with conventional electrochemical (controlled-potential electrolysis) and enzymatic (microsomal incubation) approaches. 2-OH-AC oxidation products were generated in an electrochemical thin-layer cell. Their tentative structures were assigned based on tandem mass spectrometry in combination with accurate mass measurements. Moreover, the electrochemical conversion of 2-OH-AC in the presence of reduced glutathione and/or N-acetylcysteine unveiled the formation of reactive metabolite-nucleophilic trapping agent conjugates (m/z 517 and m/z 373, respectively) via the thiol group. This glutathione S-conjugate was also identified after electrolysis experiment as well as was detected in liver microsomes. Summing up, the present work illustrates that the electrochemical simulation of metabolic reactions successfully supports the results of classical electrochemical and enzymatic studies. Therefore, it can be a useful tool for synthesis of drug metabolites, including reactive metabolites.


  • pH-dependent composite coatings for controlled drug delivery system - Review
    • Łukasz Pawłowski
    • Michał Bartmański
    • Andrzej Zieliński
    2019 Full text Inżynieria Materiałowa

    Nowadays in case of long-term implants, the most common postoperative complications are bacterial infections, which in consequence may provoke loos- ening of the implants in the primary phase of stabilization. Bacterial infections are currently the most frequent cause of revision surgery of the implants such as hip joint endoprosthesis, knee joint endoprosthesis and dental implants. In order to provide the local and long-term antibacterial cover in the tissues surrounding the implant, research is performed on materials that are carriers of drugs, which release active substances only in the case of the pH change in the system during inflammation. In consequence, biomaterials ensure antibacterial protection for a long time, not only in short post-operative period. An example of such materials are biopolymers. Biopolymers sensitive to change in pH value of the environment of live tissue that surround the implants can be used as an independent implants or as the coatings on the implants. In this case in the polymer`s matrix is dispersed often used drugs such as doxorubicin, gentamicin, vancomycin and cefuroxime. Drugs are released from this biomaterial according to three main mechanisms: diffusion, swelling and material degradation. This review paper presents the mechanism of bacterial interaction with implant surface and biofilm formation, and mechanism of drugs release from the biological active substance. Therefore, the natural and synthetic polymer materials sensitive to the lower value of pH such as chitosan, Eudragit E 100, Poly (L-histidine) and Poly (4-vinyl pyridine) are described


  • Phosphorus removal by application of natural and semi-natural materials for possible recovery according to assumptions of circular economy and closed circuit of P
    • Magda Kasprzyk
    • Magdalena Gajewska
    2019 Full text SCIENCE OF THE TOTAL ENVIRONMENT

    In the last fewyears the idea of circular economy has become essential. Thus, designing methods of nutrients removal should be based on usingmaterials that make it possible to recover those nutrients. Recently,methods applied in wastewater treatment plants cannot provide optimal results; moreover, the application of commercial coagulants like ferric chloride and polyaluminumchloride can cause difficulties in potential recovery of phosphorus fromsludge. Sorption materials, both natural and modified, are appearing as successful forwastewater treatment, especially for treatment wetland effluent. To pursue circular economy principles, the capacity of waste materials needs to be testedwith regard to nutrients removal. If in addition a possibility to recover themappears, it will be possible to close the circuit. The aim of the investigation, according to HELCOM and EU Water Framework Directive recommendations, was to explore the possibility of ensuring good and stable quality of effluent by the application of natural materials for phosphorous removal with possible minimum energy and material consumption. The objective was to determine the sorption capacity of two selected materials (waste material and chemicallymodified material) in steady conditions. The research focused also on the time ofmixing, a period of sedimentation of absorbent materials, and the influence of usedmaterials on the basic parameters of the solution: pH, temperature, total suspended solids, conductivity, turbidity, and color. M1 was a waste material after thermal treatment of carbonate-siliceous rock in temperature above 700 °C (Rockfos®). Material M2 was lanthanum-modified bentonite, a material of anthropogenic origin. Both selected materials have shown a high ability to reduce phosphates concentration in synthetic wastewater. Sorption capacity of materials M1 and M2 were 45.6 mg/g and 5.6 mg/g, respectively.


  • Photocatalytic activity of solvothermal prepared BiOClBr with imidazolium ionic liquids as a halogen sources in cytostatic drugs removal
    • Patrycja Wilczewska
    • Aleksandra Bielicka-giełdoń
    • Agnieszka Fiszka Borzyszkowska
    • Jacek Ryl
    • Tomasz Klimczuk
    • E.m. Siedlecka
    2019 Full text JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY

    In this work, the BiOClBr, as a new family of bismuth based semiconductors, was successfully applied to remove of cytostatic drugs from water under UV-Vis light irradiation. BiOCl, BiOBr and BiOClBr were synthesized using two steps solvothermal method in glycerol. The inorganic salts (KCl and KBr) and 1-butyl-3-metylimidazolium chloride (BmimCl) and 1-butyl-3-metylimidazolium bromide (BmimBr) ionic liquids (ILs) were used as the source of halides for the photocatalysts synthesis. The as-fabricated samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and UV-vis diffuse reflectance spectroscopy (DRS). The specific surface area was measured by Brauner-Emmett-Teller (BET) technique. Additionally, Fourier-transform infrared spectroscopy was used to evaluate the presence of IL on the photocatalysts surface. The comparison of photocatalytic activity between BiOCl and BiOClBr photocatalysts towards 5-fluorouracil (5-FU), imatinib (IMA) and cyclophosphamide (CP) removal was conducted. The highest photocatalytic activity in the cytostatic drugs degradation and mineralization was found using BiOClBr IL synthetized via ILs as the halogens source. The study showed that BiOClBr IL synthesized in the presence of ILs can be a promising material in the water decontamination methods.


  • Photocatalytic and Antimicrobial Properties of Ag2O/TiO2 Heterojunction
    • Maya Endo-Kimura
    • Marcin Janczarek
    • Zuzanna Bielan
    • Dong Zhang
    • Kunlei Wang
    • A. Markowska-Szczupak
    • Ewa Kowalska
    • Agata Markowska-Szczupak
    2019 Full text ChemEngineering

    Ag2O/TiO2 heterojunctions were prepared by a simple method, i.e., the grinding of argentous oxide with six different titania photocatalysts. The physicochemical properties of the obtained photocatalysts were characterized by diffuse-reflectance spectroscopy (DRS), X-ray powder diffraction (XRD) and scanning transmission electron microscopy (STEM) with an energy dispersive X-ray spectroscopy (EDS). The photocatalytic activity was investigated for the oxidative decomposition of acetic acid and methanol dehydrogenation under UV/vis irradiation and for the oxidative decomposition of phenol and 2-propanol under vis irradiation. Antimicrobial properties were tested for bacteria (Escherichia coli) and fungi (Candida albicans and Penicillium chrysogenum) under UV and vis irradiation and in the dark. Enhanced activity was observed under UV/vis (with synergism for fine anatase-containing samples) and vis irradiation for almost all samples. This suggests a hindered recombination of charge carriers by p-n heterojunction or Z-scheme mechanisms under UV irradiation and photo-excited electron transfer from Ag2O to TiO2 under vis irradiation. Improved antimicrobial properties were achieved, especially under vis irradiation, probably due to electrostatic attractions between the negative surface of microorganisms and the positively charged Ag2O.


  • Photocatalytic Decomposition of Air Pollutants using Electrodeposited Photocatalysts on Stainless Steel
    • Andreas Haenel
    • Marcin Janczarek
    • Marek Lieder
    • Jan Hupka
    2019 Full text POLISH JOURNAL OF ENVIRONMENTAL STUDIES

    The aim of research was to develop an immobilization method for photocatalysts, which is an alternative to the sol-gel or dip coating methods and can be simply scaled up for technical applications. The investigated photocatalyst was TiO2, which was electrochemically deposited onto a cathode made of stainless steel. This deposited film was photocatalytically active. In order to enhance the photoactivity of the TiO2 film, commercially available P25 photocatalyst nanoparticles were occluded into the film. The effect of deposition current density as well as the amount of occluded nanoparticles on the photocatalytic activity and photoelectrochemical behavior was investigated. The photocatalytic activity was evaluated in an UV-LED reactor. The decomposition rate of toluene and cyclohexane in air was examined for all prepared stainless steel-photocatalyst composites. It was observed that deposits prepared with 5 g dm-3 of P25 in the deposition bath showed the best photocatalytic activity and highest photocurrent.


  • Photoelectrochemically Active N‐Adsorbing Ultrathin TiO2 Layers for Water‐Splitting Applications Prepared by Pyrolysis of Oleic Acid on Iron Oxide Nanoparticle Surfaces under Nitrogen Environment
    • Ahmet Kertmen
    • Enzo Barbe
    • Mariusz Szkoda
    • Katarzyna Siuzdak
    • Višnja Babačić
    • Pau Torruella
    • Igor Iatsunskyi
    • Michał Kwiatkowski
    • Karol Rytel
    • Sonia Estrade
    • Peiró Francesca
    • Jurga Stefan
    • Li Yanguang
    • Emerson Coy
    2019 Advanced Materials Interfaces

    Highly performing photocatalytic surfaces are nowadays highly desirable in energy fields, mainly due to their applicability as photo water‐splitting electrodes. One of the current challenges in this field is the production of highly controllable and efficient photoactive surfaces on many substrates. Atomic layer deposition has allowed the deposition of photoactive TiO2 layers over wide range of materials and surfaces. However, nitrogen doping of the growing layers, a highly effective way of controlling the absorption edges of photoactive surfaced, is still a challenging task. Here, the preparation of hierarchical nanostructured surfaces based on Langmuir–Schaefer and atomic layer deposition is proposed. Ultrathin TiO2 layers that are photoelectrochemically active in water splitting are prepared by a relatively low‐temperature catalytic decomposition of oleic acid capping layers of iron oxide nanoparticles and the posterior nitrogen adsorption. The results evidence that simple N‐adsorption is sufficient to narrow the bandgap of TiO2 layers that is equal to bandgap narrowing (0.12 eV) observed for substitutionally N‐doped materials. The photocatalytic activity tests of the prepared surfaces in water‐splitting applications demonstrate ≈90% increase in the activity of the N‐adsorbing TiO2 layers.


  • Photoinduced electron transfer in 5-bromouracil labeled DNA. A contrathermodynamic mechanism revisited by electron transfer theories
    • Lorenzo Cupellini
    • Paweł Wityk
    • Benedetta Mennucci
    • Janusz Rak
    2019 PHYSICAL CHEMISTRY CHEMICAL PHYSICS

    The understanding of the 5-bromouracil (BrU) based photosensitization mechanism of DNA damage is of large interest due to the potential applications in photodynamic therapy. Photoinduced electron transfer (ET) in BrU labeled duplexes comprising the 50 -GBrU or 50 -ABrU sequence showed that a much lower reactivity was found for the 50 -GBrU pattern. Since the ionization potential of G is lower than that of A, this sequence selectivity has been dubbed a contrathermodynamic one. In the current work, we employ the Marcus and Marcus–Levich–Jortner theory of ET in order to shed light on the observed effect. By using a combination of Density Functional Theory (DFT) and solvation continuum models, we calculated the electronic couplings, reorganization energies, and thermodynamic stimuli for electron transfer which enabled the rates of forward and back ET to be estimated for the two considered sequences. The calculated rates show that the photoreaction could not be efficient if the ET process proceeded within the considered dimers. Only after introducing additional adenines between G and BrU, which accelerates the forward and slows down the back ET, is a significant amount of photodamage expected.


  • Photoluminescence of partially reduced Eu2+/Eu3+ active centers in a NaF–Al2O3–P2O5 glassy matrix with tunable smooth spectra
    • Tomasz Pietrzak
    • Agata Gołębiewska
    • Jakub Płachta
    • Michał Jarczewski
    • Jacek Ryl
    • Marek Wasiucionek
    • Jerzy Garbarczyk
    2019 Full text JOURNAL OF LUMINESCENCE

    In this work, a series of photoluminescent materials have been synthesized based on optically transparent and chemically stable glasses of the nominal composition Na3Al2(PO4)2F3 (NaF–Al2O3–P2O5 system) doped with 1 wt% of europium. It has been shown that the synthesis conditions (mainly the temperature and duration of the melting stage under reducing conditions) strongly affected the photoluminescence spectra of the material. This effect has been ascribed to varying proportions between Eu3+ and Eu2+ ions concentrations, imposed by the synthesis conditions, which was confirmed by XPS, absorption and decay times measurements. As both Eu3+ and Eu2+ centers exhibit photoluminescence in different ranges of the visible spectra (Eu3+ – red, and Eu2+ – mainly blue) the possibility, shown by us, to control relative proportions of the oxidation states of europium and consequently to control the photoluminescence spectra, may be advantageous from the viewpoint of potential applications of such materials as novel phosphors for white LEDs with the emission spectra resembling natural light


  • Phototransformation of three selected pharmaceuticals, naproxen, 17α-Ethinylestradiol and tetracycline in water: Identification of photoproducts and transformation pathways
    • Magdalena Śliwka-Kaszyńska
    • A. Jakimska-Nagórska
    • Andrzej Wasik
    • Agata Kot-Wasik
    2019 MICROCHEMICAL JOURNAL

    Transformation products (TPs) may be formed during various processes, however, it was proved that one of the main mechanisms responsible for degradation of pharmaceuticals in natural waters is photolysis. Three compounds were selected, tetracycline (TC), 17-α-ethinylestradiol (EE2) and naproxen (NAP), for degradation experiments which were performed using a xenon lamp emitting light with a spectrum closely approximating that of natural sunlight. Identification of photodegradation products was achieved via liquid chromatography coupled with high resolution quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) providing accurate mass measurements and MS/MS experiments for structural elucidation. Results indicate that degradation of compounds under the study follows pseudo-first-order kinetics. Photolysis rate constants (k) were determined and half-lifes (t1/2) calculated to be 11, 120, and 13 min for TC, EE2 and NAP, respectively. Xenon lamp irradiation led to the formation of several photoproducts. Many of them have been identified for the first time. LC-QTOF-MS analysis allowed for the identification of seven, four, and eight TPs of TC, EE2 and NAP, respectively. Finally, the presence of parent compounds and identified TPs was investigated in various real-world water samples. Only three degradation products of 17-α-ethinylestradiol and naproxen were detected in wastewater effluent and treated water samples. Quantitative structure-activity relationship (QSAR) approach was applied in order to estimate physical-chemical properties of selected pharmaceuticals and their TPs. This allowed predicting the fate of all analytes in the aqueous environment.


  • Photovoltaic effect in the single-junction DBP/PTCBI organic system under low intensity of monochromatic light
    • Rafał Marczyński
    • Justyna Szostak
    • Ryszard Signerski
    • Grażyna Jarosz
    2019 Full text CURRENT APPLIED PHYSICS

    Photoelectric properties of the planar ITO/MoO3/DBP/PTCBI/BCP/Ag system were characterized on the basis of short-circuit current, open-circuit voltage and absorption spectra, and current-voltage measurements in the dark and under monochromatic illumination of low intensity. Photovoltaic performance of the system was compared with the performance of ideal semiconductor and excitonic cells of chosen bandgaps. Such analysis shows, that the fabricated cell exhibits quite high value of the open-circuit voltage, in comparison to the SQ limits calculated for semiconductor devices of bandgaps close to the LUMOPTCBI-HOMODBP offset or crystalline silicon cells of the same absorptivity. This confirms that the DBP/PTCBI junction exhibits good properties for conversion of exciton energy to chemical energy of electron-hole pair. Moreover, open-circuit voltage and short-circuit current of the investigated cell practically do not change within the 520 nm–620 nm range, for which they reach the maximum values, making the junction of DBP/PTCBI attractive for use in indoor photovoltaics.


  • Photovoltaic Roof Tiles: The Influence of Heat Recovery on Overall Performance
    • Jan Wajs
    • Aleksandra Gołąbek
    • Roksana Bochniak
    2019 Full text ENERGIES

    A photovoltaic (PV) roof tile serves both as a roofing material and as an electricity-producing surface. The main aim of the present study was to increase the overall system efficiency of PV tiles by using heat recovery. The chosen strategy was two-fold: determine the operational efficiency of PV tiles and optimize construction to increase the cooling effect when using air as the working medium. A detailed experimental study was undertaken to determine these effects. The results indicated that a combined electrical and thermal efficiency of 24% could be reached. This is promising and proves the potential for air to be the working medium in such systems. Moreover, this shows a direction for future system optimization.