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Transparent nanocomposite coatings based on epoxy and layered double hydroxide: Nonisothermal cure kinetics and viscoelastic behavior assessments
PublicationLayered double hydroxide (LDH) has a particular place in clay family because of its flame retardant action. The nanoplatelet-like structure of LDH makes possible development of polymer composites with cationic or anionic nature structures in which macromolecules are positioned in between nanoplatelet galleries. In this work, neat epoxy and its transparent nanocomposite coatings with sodium dodecylbenzene sulfonate (SDBS)-modified...
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Global energy transition: From the main determinants to economic challenges regions
PublicationDynamic global energy transition has been accelerating for the last decade. Interestingly, the energy transition is multidimensional and concerns both the dimensions of technique/ technology and the economic, social, institu-tional, and legal spheres (Shuguang et al., 2022; Tzeremes et al., 2022; Ram-zan et al., 2022; Tzeremes et al., 2022). The literature also points to the signif-icant impact of the digitization of the global...
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Aluminium in glacial meltwater demonstrates an association with nutrient export (Werenskiöldbreen, Svalbard)
PublicationThe aluminium (Al) cycle in glacierised basins has not received a great deal of attention in studies of biogeochemical cycles. As Almay be toxic for biota, it is important to investigate the processes leading to its release into the environment. It has not yet been ascertained whether filterable Al (passing through a pore size of 0.45 m) is incorporated into biogeochemical cycles in glacierised basins. Our study aims to determine...
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Comparison of natural frequencies of a circular saw blade obtained empirically and with FEM
PublicationThe knowledge of the natural frequencies’ values of circular saw blades is necessary to determine the minimal critical rotational speed in which they can work with required stability. Moreover, testing the circular saw blades with more complicated shapes, e.g. which have additional holes inside blades for cleaning knifes or additional indirect teeth in gullets, reveals some kind of problematic properties of these saw blades. The...
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Thermal self-action effects of acoustic beam in a vibrationally relaxing gas
PublicationThermal self-action of acoustic beam in a molecular gas with excited internal degrees of molecules’ freedom, is studied. This kind of thermal self-action differs from that in a Newtonian fluid. Heating or cooling of a medium takes place due to transfer of internal vibrational energy. Equilibrium and non-equilibrium gases, which may be acoustically active, are considered. A beam in an acoustically active gas is self-focusing unlike...
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How Machine Learning Contributes to Solve Acoustical Problems
PublicationMachine learning is the process of learning functional relationships between measured signals (called percepts in the artificial intelligence literature) and some output of interest. In some cases, we wish to learn very specific relationships from signals such as identifying the language of a speaker (e.g. Zissman, 1996) which has direct applications such as in call center routing or performing a music information retrieval task...
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Wpływ zawartości grafitu na właściwości mechaniczne warstw hybrydowych Ni-P/Si3N4/grafit osadzonych na stopie AW-7075 metodą redukcji chemicznej.
PublicationPrzedstawiono wpływ obecności grafitu jako fazy dyspersyjnej na właściwości mechaniczne warstw hybrydowych Ni-P/Si3N4/grafit, które osadzono metodą redukcji chemicznej na stopie glinu AW-7075. Wykonano badania morfologii powierzchni warstw metodą mikroskopii świetlnej i skaningowej. Dalszą część pracy stanowiły badania mechaniczne, czyli pomiary mikrotwardości warstw oraz ich adhezji do aluminiowego podłoża, a także analizy wpływu...
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Podatność złączy spawanych stopów aluminium na korozję warstwową.
PublicationPrzedstawiono wyniki badań trzech stopów grup Al-Mg i Al-Zn-Mg na korozję warstwową. Wykazano, że mimo zróżnicowanego składu odporność stopów jest podobna, zaś największa korozja występuje w spoinie.
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Influence of heat transformations on microstructure and properties of some wrought aluminium alloys.
PublicationOmówiono wpływ spawania na podatność do korozji naprężeniowej stopów Al-Mg i Al-Zn-Mg stwierdzając, że wzrost zawartości cynku wywołuje wzrost właściwości mechanicznych i spadek odporności na korozję naprężeniową. Wykazano, że obróbka cieplna złożona z retrogresji i powtórnego starzenia w przypadku stopów Al-Zn-Mg nie powoduje szczególnych zmian odporności na korozję naprężeniową, co pozostaje w związku z niewielką zmianą struktur...
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Application of ionic liquids in electronic nose instruments
PublicationAmong many applications in different fields of science and technology the ionic liquids (ILs) are also utilised in chemical sensors yielding improvement of their operation parameters (Buzzeo, 2004; Wei and Ivaska, 2008; Silvester, 2011; Gebicki et al., 2013). Some of these chemical sensors are the components of the devices, which resemble human sense of smell as far as their operation is concerned. These devices are named electronic...
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Low-Dimensional Magnetic Semimetal Cr0.65Al1.35Se3
PublicationWhile exploring novel magnetic semiconductors, the new phase Cr0.65Al1.35Se3 was discovered and characterized by both structural and physical properties. Cr0.65Al1.35Se3 was found to crystallize into orthorhombic CrGeTe3-type structure with space group Pnma (no. 62). Vacancies and mixed occupancies were tested, and the results show that one of the 4c sites accommodates a mixture of Cr and Al atoms, while the other 4c site is fully...
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Analysis of airborne metal containing particles with EDX/EDS detectorsin electron microscopes
PublicationIn years 2006-2010 particulate matter analysis was undertaken for dust samples collected from Gdansk and London area in orderto compare their morphology and composition. Part of those studies was devoted to analysis of particulate matter (PM) bearingmetals. Characterization of the morphology and size of the particles collected onto the filters was performed using a scanning electronmicroscope (SEM) and transmission electron microscope...
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Deep neural networks approach to skin lesions classification — A comparative analysis
PublicationThe paper presents the results of research on the use of Deep Neural Networks (DNN) for automatic classification of the skin lesions. The authors have focused on the most effective kind of DNNs for image processing, namely Convolutional Neural Networks (CNN). In particular, three kinds of CNN were analyzed: VGG19, Residual Networks (ResNet) and the hybrid of VGG19 CNN with the Support Vector Machine (SVM). The research was carried...
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Electromodulation of photoluminescence in vacuum-evaporated films of fac-tris(2-phenylpyridine)iridium(III)
PublicationZaobserwowano silne wygaszenie fosforescencji w komórkach sandwiczowych Al/Ir(ppy)3/Al/kwarc, które w polu elektrycznym o natężeniu 3 MV/cm dochodzi do 30%. Mechanizm wygaszania jest związany z dysocjacją ekscytonów trypletowych pod działaniem zewnętrznego pola elektrycznego w obszarach zdefektowanych sieci krystalicznej.
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Laser Welding of UNS S33207 Hyper-Duplex Stainless Steel to 6061 Aluminum Alloy Using High Entropy Alloy as a Filler Material
PublicationThe high entropy alloy (HEA) filler used during the fabrication method determines the reliability of HEAs for steel-aluminum dissimilar alloy configuration. HEAs have a direct impact on the formation of intermetallic compounds (IMC) formed by the interaction of iron (Fe) and aluminum (Al), and influence the size of the joint’s interaction zone. A novel welding process for Fe-Al alloy joints was developed to prevent the development...
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Hybrid Obfuscation of Encryption
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Instantaneous Heating and Cooling Caused by Periodic or Aperiodic Sound of Any Characteristic Duration in a Gas with Vibrational Relaxation
PublicationThermodynamic relaxation of internal degrees of a molecule's freedom in a gas occurs with some characteristic time. This makes wave processes in a gas behave differently depending on the ratio of characteristic duration of perturbations and the relaxation time. In particular, generation of the secondary non-wave modes by intense sound in a nonlinear flow dependens on frequency. These kinds of interaction are considered in this...
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INFORMATION SOCIETY DEVELOPMENT TRENDS, FROM DATA THROUGH KNOWLEDGE TO WISDOM
PublicationThe paper investigates both the causes and effects of the rapid increase in the data volume(BigData)andtheirimpactonhumancognition.TheroleoftheInternetindistributing and exchanging of such data, and their impact on the growth of the Information Society are emphasized. As a result, Wisdom Science – a new kind of research – emerges which has the potential to facilitate more advanced solutions in the digital world. In consequence,...
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Automatic sound source localization in disturbing conditions using acoustic vector sensors
PublicationA concept, practical realization and applications of a passive acoustic radar to automatic localization and tracking of sound sources in disturbing conditions were presented in the paper. The device consists of the new kind of multichannel miniature sound intensity sensors and a group of digital signal processing algorithms. The sensitivity of the realized acoustic radar was examined in free sound field. Several kinds of sound...
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Geochemical fractionation of organic matter in the Jurassic-Cretaceous Vaca Muerta shale, Argentina
PublicationSeveral studies have indicated the presence of more than one generation of bitumen that could be isolated from rocks through sequential extraction or after demineralization or both. Nabbefeld et al. (2010a) and Holman et al. (2012, 2014) termed bitumen obtained after solvent extraction from the undigested rock as “Bitumen I" and that obtained by extraction after demineralization of rock as “Bitumen II.” The occurrence of different...
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Internal electric fields in vacuum-evaporated films as studied by electroabsorption spectroscopy
PublicationMierzono sygnały elektroabsorpcji na I-szej harmonicznej częstości przykładanego sinusoidalnego pola elektrycznego w komórkach sandwiczowych Al/warstwa organiczna/Al. Wyznaczono elektryczne pola wewnętrzne (Fi) dla materiałów stosowanych w organicznych diodach elektroluminescencyjnych (TPD, TAPC, MTDATA, QAC, Alq3, Ir(ppy)3, PtOEP). Mechanizm powstawania pól Fi powiązano z pułapkowaniem ładunku w obszarach przyelektrodowych.
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Polska adaptacja Metody Oceny Wypalenia Zawodowego (BAT-PL) autorstwa Schaufeliego i współpracowników
PublicationAim. The study aimed to present the Polish version of the Burnout Assessment Tool (BAT-PL) by Schaufeli et al. and to assess its validity and reliability. The tool measures the core symptoms of burnout (BAT-C): exhaustion, mental distance, cognitive and emotional impairment, and its secondary symptoms (BAT-S): psychosomatic complaints and psychological distress. Method. The participants were 255 nursing staff members....
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Review on friction stir welding of dissimilar magnesium and aluminum alloys: Scientometric analysis and strategies for achieving high-quality joints
PublicationMagnesium and aluminum alloys continually attract interest as lightweight structural materials for transport applications. However, joining these dissimilar alloys is very challenging. The main obstacle that hinders progress in dissimilar Mg-Al joining is the formation of brittle intermetallic compounds (IMCs). As a solid-state joining technique, FSW is an excellent candidate to attenuate the deleterious IMC effects in dissimilar...
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Acoustic radar employing particle velocity sensors
PublicationA concept, practical realization and applications of a passive acoustic radar to automatic localization, tracking of sound sources were presented in the paper. The device consist of the new kind of multichannel miniature sound intensity sensors and a group of digital signal processing algorithms. Contrary to active radars, it does not emit the scanning beam but after receiving surroundings sounds it provide information about the...
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Formulating a defensive technique to prevent the threat of prohibited reverse engineering
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The Efficiency of Polish Stock Market: Ordinal Patterns Approach
PublicationZunino et al. analyzed the problem of discrimination of developed and emergent markets by the use of ordinal patterns methods: number of forbidden patterns and ordinal pattern probability distribution as a basis for entropy and statistical measure of complexity. In this paper we apply the same methodology for the analysis of Polish stock market (index WIG). The results indicate that Polish market belongs neither to developed, nor...
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Investigation of corrosion behavior of 6060 and 6082 aluminum alloys under simulated acid rain conditions
PublicationInstantaneous impedance changes of 6060 and 6082 type aluminum alloys in pure water, and simulated acid rain poured into the pure water was investigated by dynamic electrochemical impedance spectroscopy (DEIS). In this way, the influence of aluminum content on the corrosion behavior of 6060 and 6082 type aluminum alloys immersed in simulated acid rain was determined. The corrosion rate of the alloy decreased with increasing Al...
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Distillery Wastes as External Carbon Sources for Denitrification in Municipal Wastewater Treatment Plants
PublicationIn order to improve efficiency of N removal within the existing capacities, the denitrification process can be enhanced by adding external carbon sources. The studies on utilization of various by-products or waste materials as alternative carbon sources for denitrification have been carried out for over 20 years (Sage et al. 2006). Among several commercially available organic compounds (such as methanol, ethanol, acetic acid, glucose),...
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Reliable method of assessing fracture properties of asymmetric bonded joints
PublicationTwo methods of assessing fracture properties of adhesive joints were studied. Two wedge tests: with continuous deflection and with force measurements were compared. Asymmetric geometry of the bonded joint was considered, i.e. two different plates of aluminium alloys: Al-Cu and Al-Mg, were bonded with epoxy DGEBA adhesive. The analytical model is shown to estimate the values of fracture properties: crack position and critical fracture...
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Chiral Schiff base complexes as an effective catalyst in Diels-Alder reaction
PublicationDiels Alder reaction is a very important tool in carbon-carbon bond formation. It is a cycloaddition between a conjugated diene and a second compound called dienophile. Where one or more heteroatoms are present in the diene and/or dienophile framework, the cycloaddition is called hetero-Diels-Alder reaction (HDA). The asymmetric Diels-Alder reaction is among the most powerful available methodologies for that construction of optically...
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Galerkin finite element analysis of Darcy–Brinkman–Forchheimer natural convective flow in conical annular enclosure with discrete heat sources
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Efektywność flotacji jonowej i precypitacyjnej mieszaniny jonów cynku i glinu
PublicationPrzedmiotem badań była ocena wpływu pH surówki oraz stężenia kolektora na efektywność półperiodycznych flotacji jonowej i precypitacyjnej, zachodzących w roztworach zawierających mieszaniny jonów Zn(II) i Al(III). Stwierdzono, iż w warunkach flotacji jonowej, zachodzących w roztworach kwaśnych, występuje konkurencja pomiędzy flotowanymi kationami w tworzeniu związków z kolektorem. Dla roztworów o pH>11 możliwa jest selektywna flotacja...
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Fractional neutron point kinetics equations for nuclear reactor dynamics – Numerical solution investigations
PublicationThis paper presents results concerning numerical solutions to a fractional neutron point kinetics model for a nuclear reactor. The paper discusses and expands on results presented in (Espinosa-Paredes et al., 2011). The fractional neutron point kinetics model with six groups of delayed neutron precursors was developed and a numerical solution using the Edwards’ method was proposed (Edwards et al., 2002). The mathematical model...
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Evidence for consolidation of neuronal assemblies after seizures in humans
PublicationThe establishment of memories involves reactivation of waking neuronal activity patterns and strengthening of associated neural circuits during slow-wave sleep (SWS), a process known as "cellular consolidation" (Dudai and Morris, 2013). Reactivation of neural activity patterns during waking behaviors that occurs on a timescale of seconds to minutes is thought to constitute memory recall (O'Keefe and Nadel, 1978), whereas consolidation...
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Zgrzewanie tarciowe z mieszaniem wewnętrznym zgrzeiny stopów aluminium AW7075-T651 i AW6082-T6 = Friction stir welding of aluminium alloys AW-7075-t651 and AW-6082-t6
PublicationW pracy przedstawione są wyniki badań nad złączami doczołowymi zgrzewanymi przy użyciu technologii Friction Stir Welding (FSW), wykonanymi z wysokowytrzymałego stopu Al-Zn (AW-7075-T651) oraz stopu Al-Mg2Si (AW-6082-T6) o wysokiej odporności na korozję. Stop AW-7075-T651 okazał się bardziej podatny na obniżenie własności mechanicznych w odniesieniu do materiału rodzimego. Złącza ze stopu AW-6082-T6 wykazały się lepszą plastycznością....
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Evaluation of occupational exposure in a slide bearings factory on the basis of urine and blood sample analyses
PublicationZbadano wpływ pracy w zakładach łożysk ślizgowych na zdrowie pracowników. Przeprowadzono analizę próbek moczu i krwi pobranych od 42 pracowników i 6 osób zatrudnionych w administracji przedsiębiorstwa, stanowiących grupę kontrolną. Oznaczono zawartość Al, Cu, Pb i Zn we krwi i moczu pracowników dwukrotnie, przed i po terapii za pomocą chelatowania, stosując ICP-MS oraz metodę dodatku wzorca. Istotność różnic w zawartości pierwiastków...
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Wpływ metodyki obliczania mózgowej objętości krwi na wiarygodność diagnozy udaru niedokrwiennego w badaniach DSC-MRI
PublicationNiedokrwienny udar mózgu jest jednym z najczęściej spotykanych oraz najlepiej udokumentowanych incydentów mózgowo-naczyniowych (Dani et al., Ann Neurol 2011, 70(3), 384-401), a obrazowanie mózgu metodą DSC-MRI (ang. Dynamic Susceptibility Contrast - Magnetic Resonance Imaging) wskazuje się jako umożliwiające m.in. diagnozę niedokrwionej tkanki, prognozę jej dalszych losów, oraz rozróżnienie niedokrwienia odwracalnego od nieodwracalnego...
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Proximity and Innovation in Clusters: How Close, How Far?
PublicationThe concept of proximity, whilst attractive cognitively, is still a poorly explored area in management sciences. The earliest publications on proximity were published at the end of the twentieth century and the development of this concept was strongly influenced by The French School of Proximity (Kirat & Lung, 1999; Rallet & Torre, 1999; Torre & Gilly, 2000; Carrincazeaux et al., 2001; Torre & Rallet, 2005). However, the most influential...
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Examination of the factors influencing binaural rendering on headphones with the use of directivity patterns
PublicationThis paper presents a study on the influence of the directional sound sources with the use of the directivity patterns. This contribution also includes a comparison to the work done by Wendt et al., where several directivity pattern designs used to gradually control the auditory source distance in a room were showed. While the tests of Wendt et al. were done by auralizing source and room using a loudspeaker ring in an anechoic...
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Global edge alliances in graphs
PublicationIn the paper we introduce and study a new problem of finding a minimum global edge alliance in a graph which is related to the global defensive alliance (Haynes et al., 2013; Hedetniemi, 2004) and the global defensive set (Lewoń et al., 2016). We proved the NP-completeness of the global edge alliance problem for subcubic graphs and we constructed polynomial time algorithms for trees. We found the exact values of the size of the...
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Ocena wpływu przejazdu pojazdów ponadnormatywnych na konstrukcje nawierzchni drogowych. Drogi krajowe i wojewódzkie klas technicznych A, S, GP, G
PublicationZagadnienie dotyczy dopuszczenia przejazdu po drogach publicznych zestawu specjalistycznego Girder Set AL 500, który służy do transportu ponadnormatywnego ładunku. Zestaw pojazdów składa się z naczepy AL 500 o maksymalnej masie całkowitej (wraz z ładunkiem) 715 ton oraz dwóch ciągników balastowych Trojan o masie 48 ton każdy. Zestaw pojazdów o tak dużej masie całkowitej będzie wywierać zdecydowanie większe oddziaływanie na konstrukcję...
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Photoconduction in the archetype organic hole transporting material TPD
PublicationW pracy przedstawiono charakterystykę fotoprzewodnictwa w zależności od przyłożonego pola elektrycznego, długości fali i natężenia światła wzbudzającego molekuły pochodnej diaminy (TPD)wykorzystywanej powszechnie jako organiczny przewodnik dziurowy w organicznych diodach elektroluminescencyjnych. Układy z pojedynczą warstwą TPD, kwarc/ITO/TPD/Al i kwarc/Al/TPD/Al, zostały wzbudzane od strony podłoża kwarcowego. Przy długościach...
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Wyznaczanie współczynnika przejmowania ciepła podczas wrzenia w przepływie dwutlenku węgla (Prediction of flow boling heat transfer coefficient for carbon dioxide in minichannels)
PublicationW pracy przedstawiono wyniki obliczeń uzyskane za pomocą własnego modelu półemirycznego dla wybranych danych eksperymentalnych dla wrzenia w przepływie dwutlenku węgla. Metoda obliczeniowa została zweryfikowana z danymi eksperymentalnymi Docoulombiera i innych (2011) oraz Mastrullo i innych (2009). Badania eksperymentalne dotyczą pełnego zakresu zmienności stopnia suchości oraz zakresu prędkości masowej G=200-1200 kg/m2s. rozwijany...
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Automotive fleet repair facility wastewater treatment using air/ZVI and air/ZVI/H2 O2 processes
PublicationAdvanced automotive fl eet repair facility wastewater treatment was investigated with Zero-Valent Iron/Hydrogen Peroxide (Air/ZVI/H2 O2 ) process for different process parameters: ZVI and H2 O2 doses, time, pH. The highest Chemical Oxygen Demand (COD) removal effi ciency, 76%, was achieved for ZVI/H2 O2 doses 4000/1900 mg/L, 120 min process time, pH 3.0. COD decreased from 933 to 227 mg/L. In optimal process conditions odor and...
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Electric-field-induced quenching of photoluminescence in photoconductive organic thin film structures based on Eu3+ complexes
PublicationW pracy badano elektrycznopolowe wygaszenie fotoluminescencji w organicznych kompleksach europu Eu(III) rozdyspergowanych w matrycy poliwęglan: dwuamina TPD. W układzie z elektrodami Al/Al obserwowano wygaszenie fotoluminescencji wywołane dysocjacją ekscytonów. W układzie z elektrodami ITO(+)/Au(-) oprócz dysocjacji ekscytonów obserwowano również silne wygaszenie ekscytonów na ładunku elektrycznym wstrzykniętym do próbki. Analiza...
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Performance of a new commercial high-definition 3D patient specific quality assurance system for CyberKnife robotic radiotherapy and radiosurgery
PublicationConventional two dimensional and low-definition measurement techniques for dosimetric verification of radiotherapy treatment deliveries are no longer adequate in the era of hypofractionation and extremely high dose gradients. New quality assurance (QA) tools with 3D capability and high definition are urgently needed. The purpose of this study was to evaluate the performance of one of the first such commercial systems as applied...
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Spectral dependences of photocurrent of the aluminium-nickel phthalocyanine-tetracene-aluminium heterojunction
PublicationAnalizowano charakterystyki spectralne fotoprądu płynącego przez heterozłącze tetracen-ftalocyjanina niklu. Obserwowany fotoprąd jest prądem dziurowym generowanym w trzech obszarach: w pobliżu obu elektrod Al i międzypowierzchni tetracen-ftalocyjanina niklu.
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Wytwarzanie oraz własności struktur nanokrystalicznych i amorficznych w warstwach wierzchnich stopów aluminium.
PublicationPrzedstawiono sposób otrzymywania nanokrystalicznych a morficznych strukur warstwy wierzchniej stopów Al-Si za pomocą Przetapiania laserowego w temperaturze ciekłego azotu. Wykazano znacznie lepszą odporność na zużycie i korozję po przetapianiu.
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Aggregation of nonionic surfactants in imidazolium ionic liquids
PublicationMicellar aggregation of surfactants in aqueous solutions has been described in terms of the balance between dispersive interactions of the hydrocarbon part of the amphiphilic molecule, and the hydration and electrostatic repulsive effects of hydrophilic head group. Changing the interactions by replacing water with another polar solvent, such as amides or glycols, has been studied to a smaller extent (Singh, Saleem et al. 1980;...
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Detection of corrosion process in marine environment by means of acoustic emission technique
PublicationW pracy przedstawiono możliwość detekcji procesu korozyjnego nieniszczącą metodą emisji akustycznej konstrukcji metalowych pracujących w środowisku wody morskiej. Pewną alternatywą wobec technik elektrochemicznych w monitorowaniu korozji zaproponowano nieniszczącą technikę emisji akustycznej. Emisja akustyczna znana jako zjawisko fizyczne i technika pomiarowa znalazły zastosowanie w detekcji korozji obiektów morskich. W związku...