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NANOCRYSTALLINE CATHODES FOR SOLID OXIDE FUEL CELLS MADE OF NOBLE METALS
PublikacjaCathodes for solid oxide fuel cells prepared by the infiltration method at 600 °C are presented. The infiltration method allows to produce stable, nanostructured electrodes. Cathodes were prepared using gold, platinum, La2NiO4+δ (L2N) and La0.6Sr0.4Co0.2Fe0.8O3 δ (LSCF). Symmetrical cathode/electrolyte/cathode samples were prepared and examined with SEM microscopy and electrochemical impedance spectroscopy. Despite successful deposition...
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The influence of anchoring group position in ruthenium dye molecule on performance of dye-sensitized solar cells
PublikacjaThe effect of anchoring group position and, in consequence, the orientation of the ruthenium dye molecule on titania surface on the performance of dye-sensitized solar cells has been studied intensively. Three model ruthenium sensitizing dyes bearing carboxylic anchoring group in ortho, meta or para position were synthesized and well characterized by spectroscopic, electrochemical, photophysical and photochemical measurements....
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Efficiency limit of excitonic photovoltaic cells under phosphor-based white LED illumination
PublikacjaThe limit of energy conversion of excitonic photovoltaic cells working under white light illumination generated by phosphor-based LED is analysed using the modified Giebink approach. Particularly, the impact of the optical energy gap and energy loss associated with the excitons dissociation at the heterojunction interface on power conversion efficiency of the device are discussed. From the results of our study it follows that the...
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Highly stable CsFAPbIBr perovskite solar cells with dominant bulk recombination at real operating temperatures
PublikacjaMixed-cation mixed-halide perovskite solar cells have been characterized in DC at different temperatures (from −20 °C up to 50 °C) and the time evolution of the device efficiency has been assessed using different degradation protocols (indoors and outdoors). The completely planar p–i–n structure is ITO/CuNiOx/PTAA/CsFAPbIBr/PCBM/PEI/Ag. Pristine current–voltage characteristics barely show hysteresis, at any temperature. Open circuit...
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Light intensity analysis of photovoltaic parameters for perovskite solar cells
PublikacjaThe number of publications on perovskite solar cells (PSC) continues to grow exponentially. Although the efficiency of PSC is exceeded 25.5%, not every research laboratory can reproduce this result or even pass the border of 20%. Unfortunately, it is not always clear which dominating mechanism is responsible for the performance drop. Here, we develop a simple method of light intensity analysis of JV parameters allowing the understanding...
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Investigation of catalytic layers on anode for solid oxide fuel cells operating with synthetic biogas
PublikacjaIn this paper solid oxide fuel cells operating with dry synthetic biogas have been examined. In order to increase their stability the layers of CuO-CeO2, Cu1.3Mn1.7O4 and Y0.08Sr0.92Ti0.8Fe0.2O3 -δ have been deposited on the Ni-YSZ anode site. These layers should catalyze the internal biogas reforming and prevent the carbon deposition on the anode site. It has been found that CuO-CeO2 and Cu1.3Mn1.7O4 catalysts led to an increase...
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Effect of Different Bromine Sources on the Dual Cation Mixed Halide Perovskite Solar Cells
PublikacjaRecent research has shown that perovskite solar cells with a mixed dual A-cation have much better structural stability without loss of efficiency than single cation devices. Mixed cation perovskites create a lot of questions about the salts being used for the formation of the best-quality layer. Here, we have investigated three sources of bromide in the perovskite absorption layer, using lead bromide (PbBr2), formamidinium bromide...
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Efficiency of exciton splitting in organic photovoltaic cells within EQE spectrum
PublikacjaThe paper presents a procedure of estimating the efficiency of exciton splitting at ED/EA interface. The procedure consists in evaluation of splitting of excitons into electron-hole pairs on the basis of the external quantum efficiency spectra of planar cells and spectra of absorbance of active organic layers. The fitting parameters are the exciton splitting probabilities at ED/EA interface. The presented procedure was applied...
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A compact seven-section rat-race hybrid coupler incorporating pbg cells
PublikacjaA conventional rat-race coupler has been doubly miniaturized: (i) characteristic impedances and electrical lengths of microstrip sections have been adequately modified as the first step of size reduction and (ii) T-shaped PBG cells have been implemented to diminish strip section length as the second step of circuit rat-race couplerminiaturization. The experimental results show good agreement with theoretical characteristics. Furthermore,...
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Expression of goose parvovirus whole VP3 protein and its epitopes in Escherichia coli cells
PublikacjaThe aim of this study was the expression of goose parvovirus capsid protein (VP3) and its epitopes in Escherichia coli cells. Expression of the whole VP3 protein provided an insufficient amount of protein. In contrast, the expression of two VP3 epitopes (VP3ep4, VP3ep6) in E. coli, resulted in very high expression levels. This may suggest that smaller parts of the GPV antigenic determinants are more efficiently expressed than the...
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Effects of Salvia officinalis and Thymus vulgaris on oxidant-induced DNA damage and antioxidant status in HepG2 cells
PublikacjaSalvia officinalis (SO) and Thymus vulgaris (TV) are medicinal plants well known for their curative powers. However, the molecular mechanisms responsible for these abilities of sage and thyme have not been fully understood yet. In this study we investigated the composition and the quantitative estimation of plant extracts, the protective effects of plant extracts against hydrogen peroxide- and 2,3-dimethoxy-1,4 naphthoquinone-induced...
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Implementation of DEIS for reliable fault monitoring and detection in PEMFC single cells and stacks
PublikacjaDynamic Electrochemical Impedance Spectroscopy (DEIS) was presented as novel method for diagnostic and monitoring of PEMFC stack and single cells operation. Impedance characteristics were obtained simultaneously with current - voltage characteristics for stack and each individual cell. Impedance measurements were performed in galvanodynamic mode. It allowed to compare performance of each cell and identification of faulty cell operation...
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Polyphenolic Characterization, Antioxidant, Antihyaluronidase and Antimicrobial Activity of Young Leaves and Stem Extracts from Rubus caesius L.
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Exploring the interfacial effects at the ETL/perovskite boundary in the semitransparent perovskite solar cells
PublikacjaThe recent focus has been made on the perovskite solar cells (PSCs) with an inverted configuration, where substantial improvements have been already achieved. However, the p–i–n structure needs a buffer layer for most of the configurations to modify the work-function of a deposited electrode. Additionally and very importantly, such a layer can also serve as a protective film that improves a stability of solar cells. Here, we study...
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Nongeminate recombination in organic bulk heterojunction solar cells: Contribution of exciton–polaron interaction
PublikacjaA new model to explain nongeminate recombination in organic bulk heterojunction solar cells is presented. We suggest that the annihilation of excitons on charge carriers at the interface between donor and acceptor phases competes with the bimolecular recombination of Coulombically bound electron–hole pairs. The exciton–polaron interaction gives visible contribution to the reduction of Langevin recombination. An analytical formula,...
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The antitumor compound triazoloacridinone C-1305 inhibits FLT3 kinase activity and potentiates apoptosis in mutant FLT3-ITD leukemia cells.
PublikacjaAim: FMS-like receptor tyrosine kinase (FLT3) is expressed in some normal hematopoietic cell types and plays an important role in the pathogenesis of acute myeloid leukemia (AML). In this study, we examined the effects of triazoloacridinone C-1305, an antitumor compound, on AML cells with different FLT3 status in vitro. Methods: A panel of human leukemic cell lines with different FLT3 status was used, including FLT3 internal tandem...
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CeCu2O4 as a functional layer on solid oxide fuel cells for synthetic biogas reforming
PublikacjaSolid Oxide Fuel Cells (SOFC) are one of the most promising electrochemical devices, which can convert chemical energy to the electrical energy these days. Their ability to work with different kind of fuel makes them noteworthy. SOFC can work with biogas. The problem arises when solid carbon starts to be deposited in anode. That leads to degradation of fuel cell. Simple solution is to apply catalytic functional layer, which is...
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Influence of excitons interaction with charge carriers on photovoltaic parameters in organic solar cells
PublikacjaWe report on theoretical analysis of excitons annihilation on charge carriers in organic solar cells. Numerical calculations based on transient one-dimensional drift-diffusion model have been carried out. An impact of three quantities (an annihilation rate constant, an exciton mobility and a recombination reduction factor) on current density and concentrations of charge carriers and excitons is investigated. Finally, we discuss...
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Design and characterization of apatite La9.8Si5.7Mg0.3O26±δ-based micro-tubular solid oxide fuel cells
PublikacjaIn this study, electrolyte-supported (Cell A) and anode-supported (Cell B) micro-tubular solid oxide fuel cells (SOFCs) based on the La9.8Si5.7Mg0.3O26±δ (LSMO) electrolyte is built through an extrusion and dip-coating processes. The formulations and process conditions for these cells are established and optimized. Both cell configurations show no visible delamination or cracking, and reaction zones and inter-diffusion of any species...
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Applications of calcium electroporation to effective apoptosis induction in fibrosarcoma cells and stimulation of normal muscle cells
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Performance and Stability in H2S of SrFe0.75Mo0.25O3-δ as Electrode in Proton Ceramic Fuel Cells
PublikacjaThe H2S-tolerance of SrFe0.75Mo0.25O3-δ (SFM) electrodes has been investigated in symmetric proton ceramic fuel cells (PCFC) with BaZr0.8Ce0.1Y0.1O3-δ (BZCY81) electrolyte. The ionic conductivity of the electrolyte under wet reducing conditions was found to be insignificantly affected in the presence of up to 5000 ppm H2S. The fuel cell exhibited an OCV of about 0.9 V at 700 °C, which dropped to about 0.6 V and 0.4 V upon exposure...
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The influence of UV light on Performance of poly(methyl methacrylate) in regard to dyesensitised solar cells
PublikacjaNiskie kosztu produkcji i prosta budowa Barwnikowych Ogniw Słonecznych (ang.DSSC-Dye Sensitized Solar Cells) a także porównywalne wydajności czynią je konkurencyjnymi wsród komercyjnych technologii ogniw słonecznych. Jednym z elementów wchodzących w skład BOS jest transparentne szkło przewodzące stanowiące jego elektrody. Doskonała transparentność omozliwia zastosowanie polimeru PMMA jako substytutu transparaentnego szkła przewodzącego....
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Targeting of FLT3-ITD kinase contributes to high selectivity of imidazoacridinone C-1311 against FLT3-activated leukemia cells
PublikacjaDrugs targeting receptor tyrosine kinase FLT3 are of particular interest since activating FLT3-internal tandem duplication (ITD) mutations abundantly occur in fatal acute myeloid leukemias (AMLs). Imidazoacridinone C-1311, a DNA-reactive inhibitor of topoisomerase II, has been previously shown to be a potent and selective inhibitor of recombinant FLT3. Here, we expand those findings by studying its effect on leukemia cells with...
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The Influence of Titania Electrode Modification with Lanthanide Ions Containing Thin Layer on the Performance of Dye-Sensitized Solar Cells
PublikacjaThe lanthanide and scandium groups ions (except Pm and Ac) have been used as dopants of TiO2 film in dye-sensitized solar cells. The X-ray diffraction spectra show that the modification has no influence on the structure of the electrode; however, the diffuse reflectance UV-Vis measurements exhibit significant changes in the electronic properties of modified electrodes. The appearance of energy barrier preventing photoexcited electron...
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Antitumor 1-nitroacridine derivative C-1748 induces significant apoptosis in pancreatic cancer cells.
PublikacjaPancreatic cancer is the fifth leading cause of cancer death and has the lowest survival rate of any solid cancer in the industrial countries. The poor prognosis of pancreatic cancer results from its tendency for late presentation, aggressive invasion, early metastasis, and resistance to chemotherapy. Gemcitabine still remains the best chemotherapeutic agent available for the treatment of advanced pancreatic cancer. However, gemcitabine...
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CYP3A4 overexpression enhances apoptosis induced by anticancer agent imidazoacridinone C-1311, but does not change the metabolism of C-1311 in CHO cells
PublikacjaWe examine whether CYP3A4 overexpression influences the rate and pattern of antitumor imidazoacridinone C-1311 metabolism, in relation to the impact of this overexpression on cell cycle progression and final cellular response of CHO cells following C-1311 treatment. Methods: Three CHO cell lines: CHO-WT, wild type, CHO-HR, overexpressing cytochrome P450 reductase (CPR) and CHO-HR-3A4, coexpressing CPR and CYP3A4 were applied....
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The impact of air humidity on the operation of proton exchange membrane fuel cells determined using dynamic electrochemical impedance spectroscopy
PublikacjaThis paper describes the changes in the fuel cell impedance across a range of current loads and humidity changes. The changes of each equivalent circuit parameters representing specific processes occurring in fuel cells, as a function of humidity and current changes, were determined. Within the combined scope of current and humidity, the optimal working conditions of the cells were determined, corresponding to the lowest impedance...
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CYP3A4-dependent cellular response does not relate to CYP3A4-catalysed metabolites of C-1748 and C-1305 acridine antitumor agents in HepG2 cells
PublikacjaHigh CYP3A4 expression sensitizes tumor cells to certain antitumor agents while for others it can lower their therapeutic ef fi cacy. We have elucidated the in fl uence of CYP3A4 overexpression on the cellular response induced by antitumor acridine derivatives, C-1305 and C-1748, in two hepatocellular carcinoma (HepG2) cell lines, Hep3A4 stably transfected with CYP3A4 isoenzyme, and HepC34 expressing empty vector. The compounds...
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Optimization of the Relative Humidity of Reactant Gases in Hydrogen Fuel Cells Using Dynamic Impedance Measurements
PublikacjaWater management is a key factor affecting the efficiency of proton exchange membrane fuel cells (PEMFCs). The currently used monitoring methods of PEMFCs provide limited information about which processes or components that humidity has a significant impact upon. Herein, we propose the use of a novel approach of impedance measurements using a multi-sinusoidal perturbation signal, which enables impedance measurements under dynamic...
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Inhibition of T-type calcium channel disrupts Akt signaling and promotes apoptosis in glioblastoma cells.
PublikacjaGlioblastoma multiforme (GBM) are brain tumors that are exceptionally resitant to both radio- and chemotherapy regimens and novel approaches to treatment are needed. T-type calcium channels are one type of low voltage-gated channel (LVCC) involved in embryonic cell proliferation and differentiation; however they are often over-expressed in tumors, including GBM. In this study, we found that inhibition of T-type Ca channels in GBM...
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Chromatographic analyses of Lavandula angustifolia and Rosmarinus officinalis extracts and their biological effects in mammalian cells and cell-free systems
PublikacjaKnowledge of biological properties of natural compounds allows to understand their therapeutic value, efficacy and security. We investigated: composition of Lavandula angustifolia (LA) and Rosmarinus officinalis (RO) extracts, their antioxidant capacity, cytotoxicity and genotoxicity, their DNA-protective potential against DNA damage induced in hamster V79 cells by several genotoxins or in plasmid DNA by Fe2+ ions and activity...
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The imidazoacridinone C-1311 induces p53-dependent senescence or p53-independent apoptosis and sensitizes cancer cells to radiation
PublikacjaC-1311 is a small molecule, which has shown promise in a number of preclinical and clinical studies. However, the biological response to C-1311 exposure is complicated and has been reported to involve a number of cell fates. Here, we investigated the molecular signaling which determines the response to C-1311 in both cancer and non-cancer cell lines. For the first time we demonstrate that the tumor suppressor, p53 plays a key role...
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Spray deposited carbon nanotubes counter electrodes for dye-sensitized solar cells
PublikacjaCarbon nanotubes due to their catalytic properties are a promising alternative to platinum counter electrodes (CE) for dye-sensitized solar cells (DSSC). In this study, counter electrodes were made from double-walled carbon nanotube (DWCNT) ink using the spray printing technique and afterwards thermally treated at temperatures ranging from 120 to 300 °C. Morphology and structure was studied using scanning electron microscopy and...
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Spray-deposited carbon-nanotube counter-electrodes for dye-sensitized solar cells
PublikacjaCarbon nanotubes due to their catalytic properties are a promising alternative to platinum counter electrodes (CE) for dye-sensitized solar cells (DSSC). In this study, counter electrodes were made from double-walled carbon nanotube (DWCNT) ink using the spray printing technique and afterwards they were thermally treated at temperatures ranging from 120 to 300 °C. Morphology and structure was studied using scanning electron microscopy...
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c-Myc Protein Level Affected by Unsymmetrical Bisacridines Influences Apoptosis and Senescence Induced in HCT116 Colorectal and H460 Lung Cancer Cells
PublikacjaUnsymmetrical bisacridines (UAs) are highly active antitumor compounds. They contain in their structure the drugs previously synthesized in our Department: C-1311 and C-1748. UAs exhibit different properties than their monomer components. They do not intercalate to dsDNA but stabilize the G-quadruplex structures, particularly those of the MYC and KRAS genes. Since MYC and KRAS are often mutated and constitutively expressed in cancer...
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Design and experimental validation of a single-stage PV string inverter with optimal number of interleaved buck-boost cells.
PublikacjaIncreasing converter power density is a problem of topical interest. This paper discusses an interleaved approach of the efficiency increase in the buck-boost stage of an inverter with unfolding circuit in terms of losses in semiconductors, output voltage ripples and power density. Main trends in the power converter development are reviewed. A losses model was designed and used for the proposed solution to find an optimal number...
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Synthetic lipopeptides as potential topical therapeutics in wound and skin care: in vitro studies of permeation and skin cells behaviour
PublikacjaSeveral Gly-His-Lys analogues were obtained to investigate their antimicrobial properties. Three lipophilic analogues with the structure numbering 1b, 2b, 4b, exhibit significant effect against bacteria and were selected for in vitro evaluation of skin cells behaviour. In the present studies, an in vitro model of wound repair, proliferative cell staining, and tracking of living cells were used. Cell proliferation and cell migration,...
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Foliate-Targeting Quantum Dots-β-Cyclodextrin Nanocarrier for Efficient Delivery of Unsymmetrical Bisacridines to Lung and Prostate Cancer Cells
PublikacjaTargeted drug delivery by nanocarriers molecules can increase the efficiency of cancer treatment. One of the targeting ligands is folic acid (FA), which has a high affinity for the folic acid receptors, which are overexpressed in many cancers. Herein, we describe the preparation of the nanoconjugates containing quantum dots (QDs) and β-cyclodextrin (β-CD) with foliate-targeting properties for the delivery of anticancer compound...
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DNA-damaging imidazoacridinone C-1311 induces autophagy followed by irreversible growth arrest and senescence in human lung cancer cells
PublikacjaImidazoacridinone 5-diethylaminoethylamino-8-hydroxyimidazoacridinone (C-1311) is an antitumor inhibitor of topoisomerase II and FMS-like tyrosine kinase 3 receptor. In this study, we describe the unique sequence of cellular responses to C-1311 in human non-small cell lung cancer (NSCLC) cell lines, A549 and H460. In A549 cells, C-1311 (IC80 = 0.08 µM) induced G1 and G2/M arrests, whereas H460 cells (IC80 = 0.051 µM) accumulated...
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PARP inhibition potentiates the cytotoxic activity of C-1305, a selective inhibitor of topoisomerase II, in human BRCA1-positive breast cancer cells
PublikacjaTwo cellular proteins encoded by the breast and ovarian cancer type 1 susceptibility (BRCA1 and BRCA2) tumor suppressor genes are essential for DNA integrity and the maintenance of genomic stability.Approximately 5-10% of breast and ovarian cancers result from inherited alterations or mutations in these genes.Remarkably, BRCA1/BRCA2-deficient cells are hypersensitive to selective inhibition of poly(ADPribose) polymerase 1 (PARP-1),...
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Synthesis of novel dinuclear ruthenium polypyridine dye for dye-sensitized solar cells application
PublikacjaA new dinuclear ruthenium(II) polypyridine complex has been successfully synthesized. The new compound has been characterized by spectroscopic and electrochemical methods. Its potential application as a sensitizing dye in dye-sensitized solar cells has been checked under AM 1.5 G irradiation conditions (100 mW cm−2) and its performance was compared to that of a commercially available mononuclear analogous dye. The overall light-to-electricity...
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Stromal-Epithelial Cross-Talk in the Intestinal Stem Cell Niche is Mediated by a Regulatory Network that Involves TGF-Beta and CTGF
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Induced Pluripotent Stem Cell (iPSC)–Derived Extracellular Vesicles Are Safer and More Effective for Cardiac Repair Than iPSCs
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Electricity generation from rapeseed straw hydrolysates using microbial fuel cells
PublikacjaRapeseed straw is an attractive fuel material for microbial fuel cells (MFCs) due to its high content of carbohydrates (more than 60% carbohydrates). This study has demonstrated that reducing sugars can be efficiently extracted from raw rapeseed straw by combination of hydrothermal pretreatment and enzymatic hydrolysis followed by utilization as a fuel in two-chamber MFCs for electrical power generation. The most efficient method...
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Magnetic field effects in dye-sensitized solar cells controlled by different cell architecture
PublikacjaThe charge recombination and exciton dissociation are generally recognized as the basic electronic processes limiting the efficiency of photovoltaic devices. In this work, we propose a detailed mechanism of photocurrent generation in dye-sensitized solar cells (DSSCs) examined by magnetic field effect (MFE) technique. Here we demonstrate that the magnitude of the MFE on photocurrent in DSSCs can be controlled by the radius and...
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Experimental review of the performances of protective coatings for interconnects in solid oxide fuel cells
PublikacjaFerritic stainless steel interconnects are used in solid oxide fuel cells; however, coatings are required to improve their performance. Although several types of coatings have been proposed, they have been scarcely investigated under similar conditions. This study compares the characteristics of uncoated Crofer 22 APU and eight different coatings on Crofer 22 APU for up to 3000 h at 800 ◦C. The coatings were deposited at various...
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Tribology of the cartilage cells in the intelligent bioreactor
PublikacjaW badaniach analityczno-numerycznych wyznaczone zostały pola prędkości przepływu lepkosprężystej, odżywczej nienewtonowskiej cieczy biologicznej, a także powstające siły tarcia w trakcie hodowli w warstwie granicznej wokoło powierzchni hodowanych komórek w bioreaktorach, stawach człowieka oraz w szczelinach mikrołożysk. Dodatkowo rozpatrywane będą przepływy potencjalne płynu stawowego z jamy stawowej, które odżywiają chrząstkę...
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Perovskites in Solid Oxide Fuel Cells
PublikacjaPrzeglądowa publikacja dotycząca wykorzystania ceramicznych materiałów perowskitowych w tlenkowych ogniwach paliwowych.
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Alternative Energy: Photovoltaic Solar Cells
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Recycling of raw materials, silicon wafers and complete solar cells from photovoltaic modules
PublikacjaPhotovoltaic modules (PVs) are an attractive way of generating electricity in reliable and maintenance-free systems with the use of solar energy. The average lifetime of photovoltaic modules is 25 to 30 years. To offset the negative impact of photovoltaic modules on the environment, it is necessary to introduce a long-term strategy that includes a complete lifecycle of all system components from the production phase through installation...