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Pathological and physiological high-frequency oscillations in focal human epilepsy
PublikacjaHigh-frequency oscillations (HFO; gamma: 40-100 Hz, ripples: 100-200 Hz, and fast ripples: 250-500 Hz) have been widely studied in health and disease. These phenomena may serve as biomarkers for epileptic brain; however, a means of differentiating between pathological and normal physiological HFO is essential. We categorized task-induced physiological HFO during periods of HFO induced by a visual or motor task by measuring frequency,...
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Dysfunctional prefrontal cortical network activity and interactions following cannabinoid receptor activation.
PublikacjaCoordinated activity spanning anatomically distributed neuronal networks underpins cognition and mediates limbic-cortical interactions during learning, memory, and decision-making. We used CP55940, a potent agonist of brain cannabinoid receptors known to disrupt coordinated activity in hippocampus, to investigate the roles of network oscillations during hippocampal and medial prefrontal cortical (mPFC) interactions in rats. During...
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Human verbal memory encoding is hierarchically distributed in a continuous processing stream
PublikacjaProcessing of memory is supported by coordinated activity in a network of sensory, association, and motor brain regions. It remains a major challenge to determine where memory is encoded for later retrieval. Here we used direct intracranial brain recordings from epilepsy patients performing free recall tasks to determine the temporal pattern and anatomical distribution of verbal memory encoding across the entire human cortex. High...
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Social Convergence in Nordic NUTS-3 Regions
PublikacjaGeographical proximity, common historical roots and collaboration within the Nordic Council make the Nordic countries, often wrongly treated as monoliths. However, in reality, Nordic regions differ in terms of broadly defined social and economic development. Issues concerning the standard of living are one of the priorities of the Helsinki Treaty signed by Nordic countries. The main goal of this paper is to analyze the existence...
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Direct determination of paraquat herbicide by square-wave voltammetry by two-step transfer mechanism at heterogeneous boron-doped carbon nanowall electrodes
PublikacjaBoron-doped carbon nanowalls (B:CNW) versus boron-doped diamond (BDD) materials were investigated for the effective electrochemical detection of highly toxic herbicide paraquat (PQ). Depending on the surface morphology and functional groups of BDD and B:CNWs, the electrochemical absorption and detection of the target analyte PQ revealed different detection mechanisms. The surface absorption mechanism was mainly observed for BDD,...
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Engineering Au nanoparticle arrays on SiO2 glass by pulsed UV laser irradiation
PublikacjaWe study semi-regular arrays of Au nanoparticles (NP) obtained via UV laser irradiation of thin Au films on glass substrate. The NP structures are prepared from films of a thickness up to 60 nm produced by discharge sputtering or pulsed laser deposition, and annealed by nanosecond laser pulses at 266 or 308 nm, respectively, at fluencies in the range of 60-410 mJ/cm2. For the rare- and close-packed NP structures, consistent description...
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Comment on "Quantitative comparison of analysis methods for spectroscopic optical coherence tomography"
PublikacjaIn a recent paper by Bosschaart et al. [Biomed. Opt. Express 4, 2570 (2013)] various algorithms of time-frequency signal analysis have been tested for their performance in blood analysis with spectroscopic optical coherence tomography sOCT). The measurement of hemoglobin concentration and oxygen saturation based on blood absorption spectra have been considered. Short time Fourier transform (STFT) was found as the best method for...
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Monte-Carlo Modeling of Optical Sensors for Postoperative Free Flap Monitoring
PublikacjaThis work aims to develop a numerical tissue model and implement software to simulate photon propagation using the Monte Carlo method to determine design guidelines for a physical measurement system. C++ was used for the simulation program, and Python as a programming environment to create an interface that allows the user to customize individual simulation elements, allowing for increased accuracy and flexibility when simulating...
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O 1s excitation and ionization processes in the CO2 molecule studied via detection of low-energy fluorescence emission
PublikacjaOxygen 1s excitation and ionization processes in the CO2 molecule have been studied with dispersed and non-dispersed fluorescence spectroscopy as well as with the vacuum ultraviolet (VUV) photon-photoion coincidence technique. The intensity of the neutral O emission line at 845 nm shows particular sensitivity to core-to-Rydberg excitations and core-valence double excitations, while shape resonances are suppressed. In contrast,...
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Photocatalytic decolourization of Rhodamine-B dye by visible light active ZIF-8/BiFeO3 composite
PublikacjaIn this work, preparation of ZIF-8 supported BiFeO3 photocatalyst by ultrasound cavitation technique was reported. The synthesized materials were characterized using solid UV absorption spectroscopy, Raman Spectroscopy, and SEM. The catalytic function of synthesized photocatalyst under ultraviolet and visible light was examined for the decolourization of Rhodamine-B (Rh-B) dye. To understand the action of the photocatalyst on Rh-B...
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Monte-Carlo Modeling of Optical Sensors for Postoperative Free Flap Monitoring
PublikacjaThis work aims to develop a numerical tissue model and implement software to simulate photon propagation using the Monte Carlo method to determine design guidelines for a physical measurement system. C++ was used for the simulation program, and Python as a programming environment to create an interface that allows the user to customize individual simulation elements, allowing for increased accuracy and flexibility when simulating...
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Synthesis and Spectroscopic Properties of New Bis-tetrazoles
PublikacjaSyntheses of N,N'-phenyltetrazole podands link with aliphatic chains containing oxygen, nitrogen and sulphur atoms, are described. The complexing properties of these compounds towards metal cations (Fe2+, Cu2+, Zn2+, Co2+, Ni2+) were investigated by absorption and infrared spectroscopy. The UV-Vis titrations were performed to estimate the stability constant values of the respective complexes with Cu2+ ion. Changes in UV-Vis absorption...
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rigid polyurethane foams modified with selected nanofillers
PublikacjaThe nanofillers: natural montmoryllonite (MMT) - Bentonite, natural MMT modified with a quaternary ammonium salt - Cloisite30B, has been used in rigid polyurethane foams (PUFs). The influence of fillers amounts on processing parameters, physical-mechanical properties (density, water absorption, brittleness and compression strength) and thermal properties (thermal stability, fire behaviours) of such foams has been analysed. The...
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Analytical chemistry in technical approaches: immobilization of biosorbent waste containing heavy metals in cemented materials
PublikacjaAn ecologically safe and economically justified method of stabilization of the used biosorbents was developed. Sorbent contaminated with heavy metals has been successfully solidified/stabilized using a hydraulic binder. The test results indicated that up to 1% of the biosorbent residue used could be added without compromising the compressive strength of the mortar. The compressive strength of the modified mortars did not change...
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Radionuclides activity and effective doses referred to geological formations
PublikacjaNaturally occurring radioactive materials (NORM) are present in Earth’s crust and they caused natural background radiation, variable in different regions. Liquid, gas and solid radionuclides emit three types of radiation – alpha, beta and gamma. Fluctuations of natural radioactivity in different geological formations in the world and in Poland were compared in relation to radiological hazard. Also drilling cuttings from boreholes...
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The Implementation of the Taxonomic Spatial Measure of Development in the Analysis of Convergence in the Standard of Living
PublikacjaThe main goal of this paper is to analyse the existence of the social convergence in the European Union between 19952012. The social convergence refers to a reduction in the dispersion of the standard of living across countries. A taxonomic spatial measure of development was used as the standard of living approximation. The use of the new approach proposed by E. Antczak allowed for an explanation of the disparities in the analysed...
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Enhanced Photoelectrocatalytical Performance of Inorganic-Inorganic Hybrid Consisting BiVO4, V2O5, and Cobalt Hexacyanocobaltate as a Perspective Photoanode for Water Splitting
PublikacjaThin layers of BiVO4/V2O5 were prepared on FTO substrates using pulsed laser deposition technique. The method of cobalt hexacyanocobaltate (Cohcc) synthesis on the BiVO4/V2O5 photoanodes consists of cobalt deposition followed by electrochemical oxidation of metallic Co in K3[Co(CN)6] aqueous electrolyte. The modified electrodes were tested as photoanodes for water oxidation under simulated sunlight irradiation. Deposited films...
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Social convergence in Nordic countries at regional level
PublikacjaResearch background: Geographical proximity, common historical roots and collaboration within the Nordic Council cause the Nordic countries to be often wrongly treated as monoliths. However, in reality, Nordic regions differ in terms of broadly defined social and economic development. Issues concerning the standard of living are one of the priorities of the Helsinki Treaty signed by Nordic countries. Purpose of the article: The...
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Tomografia perfuzyjna pCT w diagnostyce cukrzycowej mikroangiopatii płucnej
PublikacjaNiniejsza rozprawa jest poświęcona zagadnieniom diagnostyki mikroangiopatii płucnej ze szczególnym uwzględnieniem perfuzyjnej tomografii komputerowej (pCT). Retinopatia, nefropatia i neuropatia są znanymi powikłaniami cukrzycy. Mało poznany jest wpływ cukrzycy na funkcjonowanie układu oddechowego. Obecnie stosowana metoda diagnostyki cukrzycowej mikroangiopatii płucnej ma ograniczoną wiarygodność. W rozprawie została przedstawiona...
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A Novel Ru(II) Polypyridine Black Dye Investigated by Resonance Raman Spectroscopy and TDDFT Calculations
PublikacjaThe optical properties of a new(bipyridine)2Ru(4H-imidazole) complex presenting a remarkablebroad absorption in the visible range are investigated. Thestrong overlap of the absorption with the solar radiationspectrum renders the studied complex promising as a blackabsorber and hence as a starting structure for applications inthe field of dye-sensitized solar cells. The correlations betweenstructural and electronic features for...
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Desmuramylopeptydy - struktura i aktywność biologiczna = Desmuramylpeptide - structure and biological activity
PublikacjaWśród fragmentów bakteryjnych ścian komórkowych, ktore wzbudzają duże zainteresowanie, są tak zwane desmuramylopeptydy. Są to cząsteczki nie zawierające reszty kwasu muraminowego. W niniejszym artykule opisano desmuramylopeptydy, które z uwagi na swoje właściwości farmakologiczne, takie jak stymulowanie niespecyficznej odporności przeciwbakteryjnej, aktywność przeciwwirusową i przeciwnowotworową oraz synergistyczne oddziaływanie...
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The uses of the pressuremeter test for the design of north transversal tunnel in Grenoble
PublikacjaWyniki otrzymane z badań presjometrycznych wykorzystano do obliczeń statycznych za pomocą programu Extreme, którym wyznacza się wartość średnią X, odchylenie standardowe, wartość charakterystyczną Xk i rozkład teoretyczny każdego z parametrów. Obliczono wartość charakterystyczną kąta tarcia wewnętrznego dla każdego rodzaju gruntów z prawdopodobieństwem Alfa (równym 5%). Badano rozkłady: normalny, log normalny, wykładniczy, Weybulla,...
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Development of methods improving storage stability of bitumen modified with ground tire rubber: A review
PublikacjaThe following paper presents an overview of methods for improving the storage stability at high temperature of rubber modified bitumen. The storage stability of the rubber modified bitumen can be improved by using a various types of modifiers that form the bonds between the components of these binders. The increase in stability can also be achieved by using crumbrubber surface-activated by furaldehyde or ground tire rubber (GTR)...
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Electronic States of Tris(bipyridine) Ruthenium(II) Complexes in Neat Solid Films Investigated by Electroabsorption Spectroscopy
PublikacjaWe present the electric field-induced absorption (electroabsorption, EA) spectra of the solid neat films of tris(bipyridine) Ru(II) complexes, which were recently functionalized in our group as photosensitizers in dye-sensitized solar cells, and we compare them with the results obtained for an archetypal [Ru(bpy)3]2+ ion (RBY). We argue that it is difficult to establish a unique set of molecular parameter values by discrete parametrization...
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Use of optical skin phantoms for preclinical evaluation of laser efficiency for skin lesion therapy
PublikacjaSkin lesions are commonly treated using laser heating. However, the introduction of new devices into clinical practice requires evaluation of their performance. This study presents the application of optical phantoms for assessment of a newly developed 975-nm pulsed diode laser system for dermatological purposes. Such phantoms closely mimic the absorption and scattering of real human skin (although not precisely in relation to...
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Antimony substituted lanthanum orthoniobate proton conductor – structure and electronic properties.
PublikacjaX‐ray and neutron diffraction have been utilized to analyze the crystalline and electronic structure of lanthanum orthoniobate substituted by antimony. Using X‐ray absorption spectroscopy and photoelectron spectroscopy, changes in the electronic structure of the material upon substitution have been analyzed. The structural transition temperature between fergusonite and scheelite phases for 30 mol% antimony substitution was found...
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Nowe czynniki chłodnicze i zmiany w instalacjach chłodniczych. Cz.2
PublikacjaW drugiej części artykułu kontynuowany jest temat związany z ograniczeniami stosowania syntetycznych czynników chłodniczych. W części pierwszej przedstawiono tendencje do zastępowania wycofywanych substancji czynnikami naturalnymi. Niniejszy artykuł traktuje natomiast o możliwości wykorzystywania nowych, syntetycznych czynników z grupy HFO, będących substancjami bezpiecznymi dla środowiska naturalnego, w kontekście ich wpływu na...
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Redox State Sensitive Spectroscopy of the Model Compound [(H-dcbpy)(2)Ru-II(NCS)(2)](2-) (dcbpy=2,2 '-Bipyridine-4,4 '-dicarboxylato)
PublikacjaThe charge transfer reaction mechanism in a ruthenium polypyridine model complex with isothiocyanato ligands, i.e., [(H-dcbpy)(2)Ru(NCS)(2)](2-) 2Bu(4)N(+) (Ru2H) (dcbpy = 2,2'-bipyridine-4,4'-dicarboxylato), has been investigated by combining UV-vis absorption, resonance Raman spectroscopy, and electrochemical methods. Understanding the photophysics of light-harvesting complexes of this class is an indispensable prerequisite to...
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Deep Eutectic Solvents: Properties and Applications in CO2 Separation
PublikacjaNowadays, many researchers are focused on finding a solution to the problem of global warming. Carbon dioxide is considered to be responsible for the “greenhouse” effect. The largest global emission of industrial CO2 comes from fossil fuel combustion, which makes power plants the perfect point source targets for immediate CO2 emission reductions. A state-of-the-art method for capturing carbon dioxide is chemical absorption using...
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RecA Proteins from Deinococcus geothermalis and Deinococcus murrayi - Cloning, Purification and Biochemical Characterisation
PublikacjaEscherichia coli RecA plays a crucial role in recombinational processes, the induction of SOS response and mutagenic lesion bypasses. It has also been demonstrated that RecA protein is indispensable when it comes to the reassembly of shattered chromosomes in gamma-irradiated Deinococcus radiodurans, one of the most radiation-resistant organisms known. Moreover, some functional differences between E. coli and D. radiodurans RecA...
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Spray-BasedMethodforProtectingandRestoringHistoricAdobe WallsUsingNanomontmorilloniteClay
PublikacjaRestoringandprotectinghistoricbuildingsworldwideareimportant becauseheritagebuildingsarerecordsofthecivilizationsofvariouscountries.Herein, nanotechnologywasusedtorestorehistoricadobewalls.AccordingtotheIranPatent andTrademarkOffice(IRPATENT)102665,nanomontmorilloniteclayhasbeen selectedasanaturalandcompatiblematerialwithadobe.Furthermore,ithasbeenused asnanospraytobeaminimallyinvasivemethodtofillcavitiesandcracksintheadobe surface.Variouspercentagesofnanomontmorilloniteclay(1−4%)intheethanolsolvent...
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Assessment of absorbability of seamless flux cored wires stored in extreme conditions
PublikacjaWater absorption tests by gravimetric method of three specimens of seamless rutile flux cored wires for flux cored arc welding were carried out. Examined wires are characterized by varied absorbability (Wg is ranged from 0.03 to 0.11% after 200 h of moisturizing).
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Solution of coupled integral equations for quantum scattering in the presence of complex potentials
PublikacjaIn this paper, we present a method to compute solutions of coupled integral equations for quantum scattering problems in the presence of a complex potential. We show how the elastic and absorption cross sections can be obtained from the numerical solution of these equations in the asymptotic region at large radial distances.
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Designing intranet portals as electronic workplaces
PublikacjaThis paper highlights the most important requirements for developing intranet portals, especially in the areas of user interface ergonomics and usability. In specifying relevant usability requirements both perspectives are considered: of company employees and of executives. Best practices are reviewed, regarding successes and failures in intranet absorption, basing on the results on recent research in a number of surveyed Polish...
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Measurements of fundamental properties of homogeneous tissue phantoms
PublikacjaWe present the optical measurement techniques used in human skin phantom studies. Their accuracy and the sources of errors in microscopic parameters’ estimation of the produced phantoms are described. We have produced optical phantoms for the purpose of simulating human skin tissue at the wavelength of 930 nm. Optical coherence tomography was used to measure the thickness and surface roughness and to detect the internal inhomogeneities....
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Hydrothermal Cobalt Doping of Titanium Dioxide Nanotubes towards Photoanode Activity Enhancement
PublikacjaDoping and modification of TiO2 nanotubes were carried out using the hydrothermal method. The introduction of small amounts of cobalt (0.1 at %) into the structure of anatase caused an increase in the absorption of light in the visible spectrum, changes in the position of the flat band potential, a decrease in the threshold potential of water oxidation in the dark, and a significant increase in the anode photocurrent. The material...
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Dissolution of Nb-doped hydroxyapatite prepared via low-temperature mechanochemical method: Spectroscopy studies
PublikacjaCalcium phosphate glass ceramics with nominal hydroxyapatite stoichiometry doped with niobium were synthesized using simple as well as low-temperature mechanochemical method and then in the form of compressed pellet were submitted to the static dissolution process in distilled water for one month. The results of structural analysis, performed mainly on the base of spectroscopic methods such as: infrared absorption spectroscopy,...
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Visualizing spatially decomposed intermolecular correlations in the infrared spectra of aprotic liquids
PublikacjaInfrared (IR) spectroscopy is commonly used to study intermolecular interactions in the liquid phase, including solvation phenomena. On the other hand, ab initio molecular dynamics (AIMD) simulations offer the possibility to obtain IR spectra from first principles. Surpassing the experiment, AIMD simulations can deliver additional information on the spatial intermolecular correlations underlying the IR spectrum of the liquid. Although...
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Unusual odd-chain and trans-octadecenoic fatty acids in tissues of feral European beaver (Castor fiber), Eurasian badger (Meles meles) and raccoon dog (Nyctereutes procyonoides).
PublikacjaW lipidach wyizolowanych z różnych partii ciała bobrów, borsuków i jenotów stwierdzono obecność znaczących ilości niezwykłych jak na zwierzęta jednożołądkowe kwasów tłuszczowych - nieparzystowęglowych nasyconych i jednonienasyconych KT (15:0, 17:0, 15:1 i 17:1) oraz (w lipidach tkanek bobra i jenota) oktadecenowych KT konfiguracji trans, w tym kwasu wakcenowego - KT charakterystycznych dla tkanek i mleka przeżuwaczy. Obecność tych...
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Theory and application of Near-infrared spectroscopy
PublikacjaIn recent years one can observe a significant increase in the requirements on quality control in all industrial sectors. The growing number of involved analyses makes the traditional, time consuming, requiring use of large quantities of reagents, thus expansive methods inconvenient especially for industrial applications. Fortunately, there is a very fast, cheap and not invasive analytical method that is increasingly used in qualitative...
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Low to intermediate energy elastic electron scattering from dichloromethane (CH2Cl2)
PublikacjaWe report a theoretical-experimental investigation of electron scattering by dichloromethane (CH2Cl2) in the low- and intermediate energy ranges. Experimental elastic differential cross sections (DCS), in the incident electron energy range of 0.5-800 eV and scattering angle range of 10°–130°, were measured using a crossed beam relative flow technique. Integral and momentum- transfer cross sections were determined from the experimental...
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Analysis of metals in air particles from Gdańsk and London with EDX/EDS detectors in electron microscope
PublikacjaElectron microscopy with energy dispersive X-ray spectrometry (EDX/EDS) is the example of non-destructive analytical method for surface elemental analysis, with a potential detection limit of 0.1-0.5 wt.% for most elements. A spatial resolution <10 nm can be achieved using this technique, which provides a basis for the generation of quantitative and qualitative elemental data for individual particles. In order to obtain quantitative...
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Capillary Electrophoresis in determination of short - chain carboxylic acids in aqueous samples
PublikacjaAnalysis of pollution is extremely important especially in areas directly adjacent tothe residential district. Studies show that short- chain carboxylic acids are a group ofcompounds widespread around sewage treatment plants, landfills, livestock farms. The mostcommon techniques for determination of short - chain carboxylic acids are chromatographictechniques, especially gas chromatography, whose main limitation is that only volatilemonocarboxylic...
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Modelowanie przepływu ustalonego niejednostajnego w sieciach kanałów otwartych z uwzględnieniem obiektów hydrotechnicznych
PublikacjaW pracy sformułowano zagadnienie brzegowe dla równania energii opisującego przepływ ustalony niejednostajny i przedstawiono sposób jego rozwiązania przy pomocy metody różnicowej. Zaproponowana metoda obliczeń nadaje się do analizy przepływu w dendrycznych i pierścieniowych sieciach kanałów otwartych. Ponadto na przykładzie przelewu prostokątnego zaproponowano metodę uwzględnienia w obliczeniach zabudowy hydrotechnicznej. Słowa...
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DEGRADATION OF GFRP MARINE LAMINATES WITH NANO PARTICLE MODIFIED COATINGS
PublikacjaWater absorption and surface blistering behaviour was studied for polyester-matrix laminates with SiO2 nanoparticle reinforced gel coats. Accelerated water immersion tests at 37°C showed that addition of 10% nanoparticles increases blisters incubation time by ca. 50% compared to 5% and 0% nanoparticles composites.
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Two-dimensional gas chromatography – principles and application in fruits analysis
PublikacjaTwo-dimensional gas chromatography is a rapidly developing analytical technique. One of the major uses of this technique is its use for food analysis. The paper presents the principle of operation and history of this analytical technique. The specification of the two-dimensional gas chromatography technique has been discussed. The principles of separation of ingredients and application of the method, particularly in the analysis...
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Modelowanie perfuzji mózgu w badaniach MRI.
PublikacjaPraca dotyczy dynamicznego badania mózgu z wykorzystaniem techniki MRI (badanie perfuzji). W rezultacie pomiarów, tj. czasowej sekwencji skanów MRI w odpowiedzi na podanie znacznika zmieniajšcego właciwoci magnetyczne tkanek, wyznaczony zostaje model procesu perfuzji. Dla badanego procesu perfuzji opracowano model nieparametryczny (odpowied aproksymowana niezupełnš funkcjš gamma o 3 parametrach) oraz dwukompartmentowy model...
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Structural and optical investigations of sol-gel derived lithium titanate thin films
Publikacjain this paper structural and optical studies of lithium titanate (lto) thin films are presented. nanocrystalline thin films with 800 nm thickness were prepared by sol-gel method. to examine the influence of the annealing time on as-prepared films crystallization, the coatings were heated at 550 °c for 10, 20 and 80 h. structure of manufactured thin films was investigated using x-ray diffraction (xrd). the most visible lithium titanate...
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A Comprehensive Review of Phytonutrients as a Dietary Therapy for Obesity
PublikacjaObesity is a complex medical condition mainly caused by eating habits, genetics, lifestyle, and medicine. The present study deals with traditional diets like the Mediterranean diet, Nordic diet, African Heritage diet, Asian diet, and DASH, as these are considered to be sustainable diets for curing obesity. However, the bioavailability of phytonutrients consumed in the diet may vary, depending on several factors such as digestion...
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Functional Bi2O3/Gd2O3 Silica-Coated Structures for Improvement of Early Age and Radiation Shielding Performance of Cement Pastes
PublikacjaThis study presents a new approach towards the production of sol-gel silica-coated Bi2O3/Gd2O3 cement additives towards the improvement of early mechanical performance and radiation attenuation. Two types of silica coatings, which varied in synthesis method and morphology, were used to coat Bi2O3/Gd2O3 structures and evaluated...