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COMPARISON OF PREDICTIVE METHODS FOR FLOW BOILING HEAT TRANSFER IN CONVENTIONAL CHANNELS AND MINICHANNELS – THE EFFECT OF REDUCED PRESSURE
PublicationIn the paper are presented the results of follow on studies from [1]–[3] using authors own model to predict heat transfer coefficient during flow boiling. The model has been tested against a large selection of experimental data collected from various researchers to investigate the sensitivity of the in-house developed model. The collected experimental data came from various studies from literature and were conducted for the full...
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Comparison of predictive methods for flow boiling heat transfer in conventional channels and minichannels - the effect of reduced pressure
PublicationIn the paper are presented the results of follow on studies from [1]–[3] using authors own model to predict heat transfer coefficient during flow boiling. The model has been tested against a large selection of experimental data collected from various researchers to investigate the sensitivity of the in-house developed model. The collected experimental data came from various studies from literature and were conducted for the full...
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Experimental validation of pressure drop models during flow boiling of R134a – effect of flow acceleration and entrainment
PublicationA crucial step to assure proficient work of power and process apparatus is their proper design. A wide array of those devices operates within boiling or condensation of the working fluid to benefit from high heat transfer rates. Two-phase flows are associated with high heat transfer coefficients because of the latent heat of evaporation and high turbulence level between the liquid and the solid surface. Predicting heat transfer...
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Heat Transfer During Pool Boiling of Water, Methanol and R141b on Porous Coated Horizontal Tube Bundles
PublicationThis paper presents the results of experimental investigation of water, methanol and R141b refrigerant boiling on horizontal porous coated tube bundles supposed to represent a flooded-type evaporator. Experiments were carried out for a bundle of 19 tubes in triangular layout for two pitch-to-diameter ratio values – 1.7 and 2.0 – in atmospheric and sub-atmospheric pressure conditions. Average heat transfer coefficients – both local,...
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Comparison of heat transfer characteristics in surface cooling using microjets with water, ethanol and HFE7100 as test fluids
PublicationAccurate control of cooling parameters is required in ever wider range of technical applications. It is known that reducing the dimensions of the size of nozzle leads to an increase in the economy of cooling and improves its quality. Present study describes research related to the design and construction of the nozzles and microjet study, which may be applied in many technical applications such as in metallurgy, electronics, etc....
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Structural change of carbon supported Pt nanocatalyst subjected to a step-like potential cycling in PEM FC
PublicationIn this paper we present detailed X-ray absorption fine structure (XAFS), X-ray diffraction (XRD) and transmission electron microscopy (TEM) investigations of the changes in the local geometric and electronic structure of Pt nanoparticles used as a cathode catalyst in proton exchange membrane fuel cell (PEMFC), working under controlled potential cycling conditions.
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Modelling of saturated, subcooled and post-dryout flow boiling with the energy dissipation based semi-empirical model
PublicationA comprehensive semi-empirical model for saturated, subcooled and post dryout heat transfer is presented based on considerations of energy dissipation in the flow. The fundamental hypothesis in the model is the fact that heat transfer during flow boiling can be treated as a sum of two contributions constituting the total energy dissipation in the flow, namely the energy dissipation due to the shearing flow without the bubbles and...
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Recent Advances in Polymer Nanocomposites: Unveiling the Frontier of Shape Memory and Self-Healing Properties—A Comprehensive Review
PublicationShape memory and self-healing polymer nanocomposites have attracted considerable attention due to their modifiable properties and promising applications. The incorporation of nanomaterials (polypyrrole, carboxyl methyl cellulose, carbon nanotubes, titania nanotubes, graphene, graphene oxide, mesoporous silica) into these polymers has significantly enhanced their performance, opening up new avenues for diverse applications. The...
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The Use of USV to Develop Navigational and Bathymetric Charts of Yacht Ports on the Example of National Sailing Centre in Gdańsk
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Analysis of concrete behaviour under cycling within coupled elasto-plastic-damage with non-local softening
PublicationArtykuł omawia wyniki symulacji zachowania sie elementów betonowych poddanych cyklicznemu obciążeniu. Do symulacji zastosowano 3 połączone modele sprężysto-plastyczne z degradacją sztywności i z nielokalnym osłabieniem. Wyniki symulacji porównano z doświadczeniami laboratoryjnymi..
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Single-walled carbon nanotube/sulfanyl porphyrazine hybrids deposited on glassy carbon electrode for sensitive determination of nitrites
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Analysis of multi-class pharmaceuticals in fish tissues by ultra-high-performance liquid chromatography tandem mass spectrometry
PublicationA new sensitive method based on pressurized liquid extraction (PLE) and purification by gel permeation chromatography (GPC) prior to ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC–MS/MS) was developed for the determination in fish homogenate, liver and muscle of twenty pharmaceuticals compounds and metabolites from seven commonly used therapeutic families. An extensive matrix effect evaluation...
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Nonlinear impedance of vanadate glass-ceramics containing BaTiO3
Open Research DataThe nonlinear impedance of vanadate glasses doped with BaTiO3 was measured. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on a preheated (573...
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Linear impedance of vanadate glass-ceramics containing BaTiO3
Open Research DataThe linear impedance of vanadate glass-ceramics containing BaTiO3 was measured. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on a preheated...
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XPS measurements of the Fe-Pb-Si based glass
Open Research DataGlass samples with nominal compositions of xFe2O3-(50-x)PbO–50SiO2, where x = 12.5, 15, 17.5 (mol%) were prepared. Analytical grade substrates were used: Fe2O3, SiO2, and PbO. The appropriate amounts of reagents were mixed in an agate mortar. The powders obtained were melted in porcelain un-enamelled crucibles in an electric furnace at a temperature...
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Model of heat transfer in the stagnation point of rapidly evaporating microjet
PublicationThe paper presents investigation into the single water microjet surface cooling producing evaporating film. Reported tests were conducted under steady state conditions. Experiments were conducted using the nozzle size of 70 and 100 mikrometer respectively. In the course of investigations obtained were experimental relations between heat flux and wall superheating. It was proved that the phenomenon is similar to that of pool boiling...
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Structural evaluation of percolating, self-healing polyurethane–polycaprolactone blends doped with metallic, ferromagnetic, and modified graphene fillers
PublicationComposites with differently shaped micro- and nanofillers show various, unique thermal, and physicochemical properties when mixed with carefully chosen polymer matrix. Selected composition holds strategic value in achieving desired properties that is biodegradability, thermoelectric conductivity, and shape memory for organic coating. The main aim of this work is to briefly examine structural changes after reaching percolation...
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Experimental study of flow boiling pressure drop and heat transfer of R1233zd(E) at moderate and high saturation temperatures
PublicationThe paper presents the results of experimental study of flow boiling of R1233zd(E) in minichannel at moderate and high saturation temperatures. The heat transfer coefficient and pressure drop were measured for flow boiling in a stainless steel tube with 2 mm inside diameter and a length of 300 mm. Experiment has been conducted for saturation temperatures ranging from 83 to 145 °C which corresponds to values of reduced pressures...
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Soiling Effect Mitigation Obtained by Applying Transparent Thin-Films on Solar Panels: Comparison of Different Types of Coatings
PublicationDust accumulation on the front cover of solar panels is closely linked to location and orientation of photovoltaic (PV) installation. Its build-up depends on the module tilt angle, frequency of precipitation, humidity, wind strength and velocity, as well as grain size. Additionally, soil composition is determined by solar farm surroundings such as local factories, agricultural crops, and traffic. Over time, molecules of atmospheric...
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Physical and sealing properties of BaO–Al2O3–SiO2–CaO–V2O5 glasses for solid oxide fuel cell applications
PublicationIn this study, the properties of BaO–Al2O3–SiO2 (SAB) glasses incorporated with CaO and V2O5 as the network modifier and additive, respectively, are evaluated. The electrical resistivities of the glasses decrease upon the addition of CaO but increase upon increasing their V2O5 content because the V5+ species lower the ionic mobility of the glasses. The addition of V2O5 improves the wettability of the glasses on the Crofer 22 APU...
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Modelling of Ship’s Heeling and Rolling for the Purpose of Gantry Control Improvement in the Course of Cargo Handling Operations in Sea Ports
PublicationThe paper presents two proposals of models of interaction between a ship and cargo being loaded or discharged by a gantry in port, in terms of heeling and rolling of the vessel. The main purpose of such modelling is the need for improvement of gantry control with regard to faster operations thanks to more accurate estimation of level and moment of cargo release from a gantry hook or spreader. The study may be the contribution to...
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Correction to: The chemistry and toxicity of discharge waters from copper mine tailing impoundment in the valley of the Apuseni Mountains in Romania
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Badania wrzenia R22 w rurkach z powłoką porowatą. Investigation of R22 flow boiling in porous tubes.
PublicationW pracy przedstawiono wyniki pomiarów współczynnika przejmowania ciepła przy wrzeniu w przepływie R22 w poziomej rurce z aluminiową powłoką porowatą. Otrzymane dane odniesiono do wyników uzyskanych dla gładkiej stalowej rurki oraz rurki typu microfin. Rurka gładka i z powłoką porowatą była wykonana ze stali nierdzewnej o grubości ścianki 0.6 mm. Grubość powłoki porowatej wynosiła 0,2 mm. Eksperymenty prowadzono przy stopniu suchości...
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Verification of the theoretical methods for the prediction of resistance of sailing yachts based on model test results of a yacht V.O.60
PublicationWeryfikacja opiera się głównie na serii systematycznych badań modelowych wykonanych w roku 2001 w Laboratorium Hydromechaniki Okrętu WOIO PG. Zademonstrowano prognozy oporu jachtu wykonane trzema metodami z oszacowaniem i dyskusją rozbieżności wyników. Przeprowadzone badania są zorientowane na opracowanie wiarygodnego programu komputerowego dla prognozowania prędkości i innych parametrów ruchu żaglowych, regatowych jachtów oceanicznych...
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Structural evaluation of percolating, self-healing polyurethane–polycaprolactone blends doped with metallic, ferromagnetic, and modified graphene fillers
PublicationComposites with differently shaped micro- and nanofillers show various, unique thermal, and physicochemical properties when mixed with carefully chosen polymer matrix. Selected composition holds strategic value in achieving desired properties that is biodegradability, thermoelectric conductivity, and shape memory for organic coating. The main aim of this work is to briefly examine structural changes after reaching percolation threshold...
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A common method for calculation of flow boiling and flow condensation heat transfer coefficients in minichannels with account of nonadiabatic effects
PublicationW pracy przedstawiono metodę ogólną wyznaczania współczynników przejmowania ciepła podczas wrzenia w przepływie i kondensacji w przepływie w minikanałach z uwzględnieniem efektu nieadiabatycznego. Uwzględnia ona wpływ modyfikacji naprężeń stycznych na granicy ciecz-para na wymianę ciepła.
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A semi-empirical method for calculation of flow boiling heat transfer coefficients for conventional channels and small diameter tubes
PublicationW pracy przedstawiono rozważania na temat modelowania dwufazowego przepływu wrzącego w kanałach konwencjonalnych i w kanałach o małej średnicy. Przedstawiono modyfikację korelacji zaproponowanej wcześniej przez J. Mikielewicza na podstawie nowych danych eksperymentalnych, uzyskanych dla kanałów o małej średnicy. Bank danych obejmował ponad 460 punktów pomiarowych dla czynników R141b, R134a, R113, R123, R12, R11 i wody. Uzyskano...
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Improved semi-empirical method for determination of heat transfer coefficient in flow boiling in conventional and small diameter tubes
PublicationPraca dotyczy przedstawienia poprawionego modelu umożliwiającego wyznaczanie współczynnika przejmowania ciepła w kanałach o małych średnicach jaj i tych tradycyjnych. Model zweryfikowano na 6 czynnikach chłodnuiczych uzyskując bardzo zadowalającą zgodność.
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Three-Dimensional Thematic Map Imaging of the Yacht Port on the Example of the Polish National Sailing Centre Marina in Gdańsk
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The analgesic hybrid of dermorphin/substance P and analog of enkephalin improve wound healing in streptozotocin‐induced diabetic rats
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Autologous Platelet-Rich Plasma Reduces Healing Time of Chronic Venous Leg Ulcers: A Prospective Observational Study
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Measuring moisture damage of asphalt mixtures: The development of a new modified boiling test based on color image processing
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Hydrogel Delivery System Containing Calendulae flos Lyophilized Extract with Chitosan as a Supporting Strategy for Wound Healing Applications
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Non-isothermal effects in a common method for calculation of heat transfer coefficient in flow boiling and flow condensation in minichannels
PublicationW pracy przestawiono efekty nieizotermiczne w metodzie wyznaczania współczynnika przejmowania ciepła podczas wrzenia w przepływie oraz kondensacji w przepływie w minikanałach. Wyniki obliczeń porównano z badaniami eksperymentalnymi z literatury, uzyskując dobrą zgodność.
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Neotenic phenomenon in gene expression in the skin of Foxn1- deficient (nude) mice - a projection for regenerative skin wound healing
PublicationMouse fetuses up to 16 day of embryonic development and nude (Foxn1- deficient) mice are examples of animals that undergo regenerative (scar-free) skin healing. The expression of transcription factor Foxn1 in the epidermis of mouse fetuses begins at embryonic day 16.5 which coincides with the transition point from scar-free to scar-forming skin wound healing. In the present study, we tested the hypothesis that Foxn1 expression...
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Experimental investigation of M-shape heat transfer coefficient distribution of R123 flow boiling in small-diameter tubes
PublicationW publikacji przedstawiono wyniki badań wrzenia czynnika R123 w srebrnych rurkach o małych średnicach (średnice wewnętrzne wynosiły odpowiednio 1.15 mm i 2.3 mm). Badania przeprowadzono w szerokim zakresie stopnia suchości pary (0.01-0.9), gęstości strumienia masy (650-3000 kg/(m2s)) oraz gęstości strumienia ciepła (40-80 kW/m2). W badaniach wykazano, że istnieją dwa lokalne maksima współczynnika przejmowania ciepła w jego profilu...
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Reduced graphene oxide/iron(II) porphyrazine hybrids on glassy carbon electrode for amperometric detection of NADH and L-cysteine
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Photoluminescence of partially reduced Eu2+/Eu3+ active centers in a NaF–Al2O3–P2O5 glassy matrix with tunable smooth spectra
PublicationIn 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...
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A 0.5-V bulk-driven voltage follower / DC level shifter and its application in class AB output stage
PublicationA simple realization of a 0.5-V bulk-driven voltage follower/DC level shifter, designed in a 0.18um CMOS technology is presented in the paper. The circuit is characterized by large input and output voltage swings, and a DC voltage gain close to unity. The DC voltage shift between input and output terminals can be regulated in a certain interval around zero, by means of biasing current sinks. An application of the proposed voltage...
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Anthra[1,2-d][1,2,3]triazine-4,7,12(3H)-triones as a New Class of Antistaphylococcal Agents: Synthesis and Biological Evaluation
PublicationThe development and spread of resistance of human pathogenic bacteria to the action of commonly used antibacterial drugs is one of the key problems in modern medicine. One of the especially dangerous and easily developing antibiotic resistant bacterial species is Staphylococcus aureus. Anthra[1,2-d][1,2,3]triazine-4,7,12(3H)-triones 22–38 have been developed as novel effective antistaphylococcal agents. These compounds have been...
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Influence of synthesis conditions on glass formation, structure and thermal properties in the Na 2 O-CaO-P 2 O 5 system doped with Si 3 N 4 and Mg
PublicationOxynitride phosphate glasses and glass-ceramics were prepared using new synthesis routes for phosphate glasses. Materials were melted from pre-prepared glass samples in the system Na-Ca-P-O with addition of Mg and/or Si3N4 powders under different preparation conditions. The melting process was conducted at 1000–1500 °C either under air or nitrogen atmosphere to obtain materials with different nitrogen content. Their topography...
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XRD patterns of V2O5 thin films deposited on quartz glass
Open Research DataThe DataSet contains the XRD patterns of V2O5 thin films deposited on a quartz glass substrate. The as-prepared thin films were annealing under an oxidizing atmosphere in the temperature range 200-600C. The results show that the structure of the films dependent on the annealing temperature.
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Nonlinear high temperature impedance of 35P2O5-30Fe2O3-35Nb2O5 glass
Open Research DataThe nonlinear high temperature impedance of iron- phosphate glasses doped with niobium oxide was measured. Glass samples of the composition of 35P2O5-30Fe2O3-35Nb2O5 (in %mol) were prepared by the conventional melt quenching technique. Appropriate amounts of reagents ((NH4)2HPO4 (≥99.9%, POCH), Fe2O3 (≥99.9%, POCH) and Nb2O5 (≥99.9%, PLUKA AG) were...
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Tellurite based glass doped by Eu3+ ions - XPS measurements
Open Research DataEu3+ doped tellurite glass ceramics containing SrF2 nanocrystals were prepared using melt quenching technique and subsequent heat treatment of glass in 370 °C for different time periods. Thermal properties of glass matrix have been determined based on DSC measurements. XRD and XPS results confirmed formation of SrF2 nanocrystals in glass matrices after...
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Detection of the Ag nanoparticles in Te-Bi-Ba-Oa glass
Open Research DataThe influence of the manufacturing parameters of tellurium-bismuth-barium glasses on the presence of silver nanoparticles was investigated. Glasses were annealed at 330, 335, 340, 345 and 350 degrees Celsius for 24 and 48 hours. Presence of the Ag nanoparticles was measured by XPS method. The growth of nanoparticles was observed along with the extension...
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The New LM-PCR/Shifter Method for the Genotyping of Microorganisms Based on the Use of a Class IIS Restriction Enzyme and Ligation Mediated PCR
PublicationThis study details and examines a novel Ligation-Mediated - Polymerase Chain Reaction (LM-PCR) method. Named the LM-PCR/Shifter, it relies on the use of a Class IIS restriction enzyme giving restriction fragments with different 4 base, 5' overhangs, this being the Shifter, and the ligation of appropriate oligonucleotide adapters. A sequence of 4-base, 5' overhangs of the adapter and a 4-base sequence of the 3' end of the primer(s)...
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A Zn-Dependent Metallopeptidase Is Responsible for Sensitivity to LsbB, a Class II Leaderless Bacteriocin of Lactococcus lactis subsp. lactis BGMN1-5
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Reducing the number of periodic points in the smooth homotopy class of a self-map of a simply-connected manifold with periodic sequence of Lefschetz numbers
PublicationLet f be a smooth self-map of an m-dimensional (m >3) closed connected and simply-connected manifold such that the sequence of the Lefschetz num- bers of its iterations is periodic. For a fixed natural r we wish to minimize, in the smooth homotopy class, the number of periodic points with periods less than or equal to r. The resulting number is given by a topological invariant J[f] which is defned in combinatorial terms and is...
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Weighted Ensemble with one-class Classification and Over-sampling and Instance selection (WECOI): An approach for learning from imbalanced data streams
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Multiwalled carbon nanotube/sulfanyl porphyrazine hybrids deposited on glassy carbon electrode — effect of nitro peripheral groups on electrochemical properties
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