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Study on the Positioning Accuracy of the GNSS/INS System Supported by the RTK Receiver for Railway Measurements
PublicationCurrently, the primary method for determining the object coordinates is positioning using Global Navigation Satellite Systems (GNSS) supported by Inertial Navigation Systems (INS). The main goal of this solution is to ensure high positioning availability, particularly when access to satellite signals is limited (in tunnels, areas with densely concentrated buildings and in forest areas). The aim of this article is to determine whether...
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Manoeuvring forces on azimuthing podded propulsor model
PublicationThis paper presents the preliminary part of comprehensive manoeuvring open- water tests of a gas carrier model. The paper focuses on open water experiments with an azimuthing podded propulsor. The test program was carried out in the cavitation tunnel and the large towing tank of Ship Hydromechanics Division, Ship Design and Research Centre, Gdańsk. The pod was tested as a pushing unit with a 161.3 mm diameter propeller. Steering...
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Enhanced photocatalytic activity of accordion-like layered Ti3C2 (MXene) coupled with Fe-modified decahedral anatase particles exposing {1 0 1} and {0 0 1} facets
PublicationNew composites consisting of decahedral anatase particles exposing {001} and {101} facets coupled with accordion-like layered Ti3C2 with boosted photocatalytic activity towards phenol and carbamazepine degradation were investigated. The photocatalysts were characterized with X-ray diffraction (XRD), diffuse reflectance spectroscopy (DR/UV–Vis), Brunauer-Emmett-Teller (BET) specific surface area, Raman spectroscopy, scanning electron...
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Insight into Potassium Vanadates as Visible-Light-Driven Photocatalysts: Synthesis of V(IV)-Rich Nano/Microstructures for the Photodegradation of Methylene Blue
PublicationPhotocatalysis is regarded as a promising tool for wastewater remediation. In recent years, many studies have focused on investigating novel photocatalysts driven by visible light. In this study, K2V6O16·nH2O nanobelts and KV3O8 microplatelets were synthesized and investigated as photocatalysts. Samples were obtained via the facile method based on liquid-phase exfoliation with ion exchange. By changing the synthesis temperature...
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Preparation and photocatalytic activity of Nd-modified TiO2 photocatalysts: Insight into the excitation mechanism under visible light
PublicationTitanium dioxide (TiO2) nanoparticles (NPs) modified with neodymium (Nd) in the range between 0.1 and 1.0 mol% were prepared via the hydrothermal method. The samples obtained were characterized by diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), X-ray fluorescence (EDX), Brunauer–Emmett–Teller (BET) method, X-ray powder diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS) and photoluminescence...
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Visible light photocatalysis employing TiO2/SrTiO3-BiOI composites: Surface properties and photoexcitation mechanism
PublicationA series of binary TiO2/SrTiO3 and ternary TiO2/SrTiO3_BiOI composites have been synthesized using multistep preparation method. Characterization of the obtained photocatalysts covered complex analysis including morphology + y (SEM), BET specific surface area, porosity, optical properties (DRS), chemical composition of surface (XPS), crystal structure and crystal size (XRD). UV–vis and Vis ligh induced photocatalytic activity was...
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Hybrid TiO2–Polyaniline Photocatalysts and their Application in Building Gypsum Plasters
PublicationHybrid materials of conjugated polymer and titanium(IV) oxide have attracted considerable attention concerning their potential benefits, including (i) ecient exploitation of visible light, (ii) a high adsorption capacity for organic contaminants, (iii) and eective charge carriers separation. The new class of the photocatalysts is promising for the removal of environmental pollutants in both aqueous and gaseous phases. For the first...
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Innowacyjny moduł ultradźwiękowy systemu monitoringu technicznego mostu podwieszonego w Rzeszowie
PublicationW artykule przedstawiono system monitoringu technicznego konstrukcji mostu podwieszonego nad rzeką Wisłok. System będzie wyposażony w dodatkowy moduł ultradźwiękowy umożliwiający śledzenie degradacji mechanicznej betonu w pylonie mostu. Wczesne wykrywanie stref mikropęknięć, przed pojawieniem się widocznych rys, umożliwia monitorowanie amplitud propagującej fali ultradźwiękowej oraz analizę sygnałów w dziedzinie częstotliwości.
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HDAC Inhibitors: Innovative Strategies for Their Design and Applications
PublicationHistone deacetylases (HDACs) are a large family of epigenetic metalloenzymes that are involved in gene transcription and regulation, cell proliferation, differentiation, migration, and death, as well as angiogenesis. Particularly, disorders of the HDACs expression are linked to the development of many types of cancer and neurodegenerative diseases, making them interesting molecular targets for the design of new efficient drugs...
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Insights into Seawater Biodegradation of Sustainable Mater-Bi/Poly(ε-caprolactone)-Based Biocomposites Filled with Diisocyanate-Modified Cellulose Particles
Publication: Due to rapid economic growth, the use of plastics in almost all areas of human life has significantly increased over recent decades, leading to massive pollution. Therefore, works dealing with sustainable and biodegradable polymer materials are vital now. Herein, sustainable MaterBi/poly(ε-caprolactone) (PCL)-based biocomposites, filled with diisocyanate-modified cellulose particles, were prepared and subjected to 12-week seawater...
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System wykrywania i przeciwdziałania spoofingowi GPS
PublicationSpoofing w systemach nawigacji satelitarnej jest atakiem elektronicznym, który polega na nieuprawnionej emisji sygnałów stanowiących imitacje rzeczywistych sygnałów odbieranych z satelitów. Powoduje on wyznaczenie nieprawidłowych informacji o czasie, położeniu i prędkości odbiornika. Z uwagi na trudność jego wykrycia, spoofing stanowi poważniejsze zagrożenie niż proste zagłuszanie sygnałów zakłóceniem o dużej mocy (ang. jamming)....
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Badania charakterystyki obciążeń oddziałujących na modułowe urządzenie dylatacyjne w pasie ruchu ciężkiego autostrady A8
PublicationPrzedstawiono badania urządzenia dylatacyjnego typu nożycowego. Dokonano statycznych i dynamicznych pomiarów odkształceń oraz przemieszczeń konstrukcji nożyc na najbardziej obciążonym pasie autostrady A8. Określono wpływ oddziaływania dynamicznego oraz sporządzono histogramy obciążeń i współczynników przewyższenia dynamicznego na podstawie pomiarów ciągłych w okresie nasilonego ruchu. Wskazano przyczyny degradacji urządzenia. Odniesiono...
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Detection of the Direct Sequence Spread Spectrum Signals with BPSK Modulation
PublicationThis paper presents a method of the DS CDMA signals with BPSK modulation detection through the examination of the enhanced signal spectrum density. On the base of experiments carried out on the real radio communication signals the impact of a narrowband emission occurring in the examined frequency band on the detection process effectiveness was shown. The results of the experiment aimed at the detection of the satellite navigation...
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BADANIE I ANALIZA WYBRANYCH PARAMETRÓW UŻYTKOWYCH NAZIEMNEGO SYSTEMU RADIOLOKALIZACYJNEGO AEGIR
PublicationMimo olbrzymiej popularności radionawigacyjnych systemów satelitarnych GNSS (Global Navigation Satelite System), naziemne systemy radiolokalizacyjne są cały czas rozwijane. W artykule przedstawiono wyniki analizy wybranych parametrów użytkowych systemu AEGIR, który powstał w ramach projektu badawczo-rozwojowego numer O R00 0049 06 w latach 2009-2011.
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Machine Learning and Text Analysis in an Artificial Intelligent System for the Training of Air Traffic Controllers
PublicationThis chapter presents the application of new information technology in education for the training of air traffic controllers (ATCs). Machine learning, multi-criteria decision analysis, and text analysis as the methods of artificial intelligence for ATCs training have been described. The authors have made an analysis of the International Civil Aviation Organization documents for modern principles of ATCs education. The prototype...
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Analiza symulacyjna wybranych algorytmów dostarczania paczek wiadomości w sieci DTN na Bałtyku
PublicationJedną z dróg zwiększania bezpieczeństwa żeglugi morskiej jest zapewnienie powszechnej dostępności usług e-nawigacji na obszarach morskich pozbawionych dostępu do Internetu. W artykule opisano wyniki symulacji wybranych algorytmów przekazywania wiadomości usług niewrażliwych na opóźnienia w znacznej odległości od lądu, w sieci o nieciągłej i sporadycznej łączności.
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DOP and Pseudorange Error Estimation in Mobile GNSS Systems for Android OS Applications
PublicationIn the near past, GNSS (Global Navigation Satellite Systems) were only offered for a narrow group of recipients. Nowadays, thanks to mobile devices, they are available to anyone and everywhere. Personal navigation, searching for POI (Point of Interest), etc., had become a basic essential activity. Thanks to the widespread and availability of smartphones each user can obtain information considering his or her location even in an...
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Concept of an Innovative Autonomous Unmanned System for Bathymetric Monitoring of Shallow Waterbodies (INNOBAT System)
PublicationBathymetry is a subset of hydrography, aimed at measuring the depth of waterbodies and waterways. Measurements are taken inter alia to detect natural obstacles or other navigational obstacles that endanger the safety of navigation, to examine the navigability conditions, anchorages, waterways and other commercial waterbodies, and to determine the parameters of the safe depth of waterbodies in the vicinity of ports, etc. Therefore,...
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DOP and Pseudorange Error Estimation in Urban Environments for Mobile Android GNSS Applications
PublicationJust a couple of years ago, GNSS (Global Navigation Satellite Systems) were available only for a narrow group of users. Currently, with the outbreak of mobile devices, they are accessible to anyone and everywhere. Urban navigation or searching for POIs (Points of Interest) had become an everyday activity. With the availability of consumer electronics and wireless technologies, each user can obtain information considering his or...
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Automatic Watercraft Recognition and Identification on Water Areas Covered by Video Monitoring as Extension for Sea and River Traffic Supervision Systems
PublicationThe article presents the watercraft recognition and identification system as an extension for the presently used visual water area monitoring systems, such as VTS (Vessel Traffic Service) or RIS (River Information Service). The watercraft identification systems (AIS - Automatic Identification Systems) which are presently used in both sea and inland navigation require purchase and installation of relatively expensive transceivers...
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Diffusible Hydrogen Control in Flux Cored Arc Welding Process
PublicationOne of the types of hydrogen degradation of steel welded joints is cold cracking. The direct cause of the formation of cold cracks is simultaneous presence of hydrogen, residual stresses and brittle structure. The way of preventing the occurring of degradation is to eliminate at least one of these factors. Practice has shown that the best solution is to control the amount of hydrogen in deposited metal. In this paper an experimental...
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Experimental and numerical investigations of ultimate strength of imperfect stiffened plates of different slenderness
PublicationThe objective of this study is to analyse the behaviour of compressed stiffened plates of different slenderness using experimental and numerical methods. The presented results are part of a long-term project to investigate the ultimate strength of geometrically imperfect structures subjected to different degradation phenomena, including corrosion degradation and locked cracks. Several specimens were subjected to a uniaxial compressive...
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Tuning the photocatalytic performance through magnetization in Co-Zn ferrite nanoparticles
PublicationIn this work, the link between the photocatalytic performance of Co-Zn ferrite nanoparticles and the net magnetic moment is analyzed. CoxZn1-xFe2O4 nanoparticles (0 ≤ x ≤ 1) were synthesized by co-precipitation method and different physicochemical techniques were employed to characterize the samples (X-ray diffraction, Transmission Electron Microscopy (TEM), BET surface area, Diffuse Reflectance Spectroscopy (DRS), Photoluminescence spectroscopy,...
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Carbon nitride exfoliation for photocatalysis and photocatalytic ozonation over emerging contaminants abatement
PublicationThe production of graphitic carbon nitride was studied with the addition of a following exfoliation step using ultrasounds, at different times. The treatment produced catalysts with much higher surface areas, from 2.18 m2 g 1 with no treatment to 28.34 m2 g 1 after 36 h of exfoliation. During exfoliation, melem was also produced, and may further enhance the photoluminescence and photocatalytic properties. The photocatalytic reaction...
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Numerical Modelling of Connections Between Stones in Foundations of Historical Buildings
PublicationThe aim of this paper is to analyse the behaviour of old building foundations composed of stones (the main load-bearing elements) and mortar, based on numerical analysis. Some basic aspects of historical foundations are briefly discussed, with an emphasis on their development, techniques, and material. The behaviour of a foundation subjected to the loads transmitted from the upper parts of the structure is described...
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Vegetable derived-oil facilitating carbon black migration from waste tire rubbers and its reinforcement effect
PublicationThree dimensional chemically cross-linked polymer networks present a great challenge for recycling and reutilization of waste tire rubber. In this work, the covalently cross-linked networks of ground tire rubber (GTR) were degraded heterogeneously under 150 °C due to the synergistic effects of the soybean oil and controlled oxidation. The degradation mechanism was discussed using Horikx theory and Fourier transformation infrared...
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Failure Monitoring and Condition Assessment of Steel-Concrete Adhesive Connection Using Ultrasonic Waves
PublicationAdhesive bonding is increasingly being incorporated into civil engineering applications. Recently, the use of structural adhesives in steel-concrete composite systems is of particular interest. The aim of the study is an experimental investigation of the damage assessment of the connection between steel and concrete during mechanical degradation. Nine specimens consisted of a concrete cube and two adhesively bonded steel plates...
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The effect of metal cluster deposition route on structure and photocatalytic activity of mono- and bimetallic nanoparticles supported on TiO2 by radiolytic method
PublicationTiO2 (P25) was modified with small and relatively monodisperse mono- and bimetallic clusters (Ag, Pd, Pt, Ag/Pd, Ag/Pt and Pd/Pt) induced by radiolysis to improve its photocatalytic activity. The as-prepared samples were characterized by X-ray fluorescence spectrometry (XRF), photoluminescence spectrometry (PL), diffuse reflectance spectroscopy (DRS), X-ray powder diffractometry (XRD), scanning transition electron microscopy (STEM)...
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The chemistry of river–lake systems in the context of permafrost occurrence (Mongolia, Valley of the Lakes) Part II. Spatial trends and possible sources of organic composition
PublicationThe chemistry of river–lake systems located in Central Mongolia near the southern border of permafrost occurrence has not been well studied. The main aim of this paper is to summarize patterns in water chemistry in supply springs, rivers and lakes in relation to permafrost occurrence, as well as other natural and anthropogenic impacts. The analyses involved water samples taken from two river–lake systems: the Baydrag River–Böön...
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An Overview of Treatment Approaches for Octahydro-1, 3, 5, 7-tetranitro-1, 3, 5, 7-tetrazocine (HMX) Explosive in Soil, Groundwater, and Wastewater
PublicationOctahydro-1, 3, 5, 7-tetranitro-1, 3, 5, 7-tetrazocine (HMX) is extensively exploited in the manufacturing of explosives; therefore, a significant level of HMX contamination can be encountered near explosive production plants. For instance, up to 12 ppm HMX concentrations have been observed in the wastewater effluent of a munitions manufacturing facility, while up to 45,000 mg/kg of HMX has been found in a soil sample taken from...
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5-Selenocyanato and 5-trifluoromethanesulfonyl derivatives of 2′-deoxyuridine: synthesis, radiation and computational chemistry as well as cytotoxicity
Publication5-Selenocyanato-2′-deoxyuridine (SeCNdU) and 5-trifluoromethanesulfonyl-2′-deoxyuridine (OTfdU) have been synthesized and their structures have been confirmed with NMR and MS methods. Both compounds undergo dissociative electron attachment (DEA) when irradiated with X-rays in an aqueous solution containing a hydroxyl radical scavenger. The DEA yield of SeCNdU significantly exceeds that of 5-bromo-2′-deoxyuridine (BrdU), remaining...
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Non invasive optical cellular imaging in humans.
PublicationOne of the most appealing and still unsolved problems in biological and medical imaging is the possibility of noninvasive visualization of tissue in vivo with an accuracy of microscopic examination. A major difficulty to solve in biomedical imaging is a degradation of image quality caused by the presence of optical inhomogeneity of tissue. Is there any chance to develop a microscopic method that allows non-invasive observation...
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Experimental Verification of the CFD Model of the Squeeze Film Lifting Effect
PublicationAbstract: The presented study shows the results of the research into the squeeze film levitation phenomena. The system introduced in the investigation is composed of a vibrating surface, air squeeze film, and the surface of the body freely suspended over the film. The use of the CFD (Computational Fluid Dynamics) model used in the system allows us to determine the steady state, periodic behavior of the air film (described by Navier–Stokes,...
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Towards Contactless, Hand Gestures-Based Control of Devices
PublicationGesture-based intuitive interactions with electronic devices can be an important part of smart home systems. In this paper, we adapt the contactless linear gesture sensor for the navigation of smart lighting system. Set of handled gestures allow to propose two methods of active light source selection, continuous dimming, and turning on and off based on discrete gestures. The average gesture recognition accuracy was 97.58% in the...
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Special Issue: Recent Advances in Corrosion Science
PublicationThe dynamic development of the global industry and growing demand for new material technologies generates constantly increasing problems regarding premature material degradation and the requirement to determine corrosion mechanisms and to develop new protection/evaluation approaches. This Special Issue, “Recent Advances in Corrosion Science”, brings together fourteen articles and one review, providing a snapshot of the recent activity...
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Cooperative Word Net Editor for Lexical Semantic Acquisition
PublicationThe article describes an approach for building Word Net semantic dictionary in a collaborative approach paradigm. The presented system system enables functionality for gathering lexical data in a Wikipedia-like style. The core of the system is a user-friendly interface based on component for interactive graph navigation. The component has been used for Word Net semantic network presentation on web page, and it brings functionalities...
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Information transfer during the universal gravitational decoherence
PublicationRecently Pikovski et al. (Nat Phys 11:668, 2015) have proposed in an intriguing universal decoherence mechanism, suggesting that gravitation may play a conceptually important role in the quantum-to-classical transition, albeit vanishingly small in everyday situations. Here we analyze information transfer induced by this mechanism. We show that generically on short time-scales, gravitational decoherence leads to a redundant information...
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An approach for the response of buildings subjected to impact load after soft-story failure due to earthquake excitation
Publicationhe soft-story failure is one of the most typical types of damage observed in buildings during earthquakes. The failure of an intermediate soft story of a structure results in large impact loading acting on the lower floors due to the fall of the upper stories. The aim of the present paper is to study the behavior of the structural members exposed to such extreme load conditions occurring under ground motion excitation. Special...
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TiO2-based magnetic nanocomposites with core-shell structure
PublicationThe main aim of the doctoral dissertation was preparation and characterization of photocatalysts, with particular emphasis on modified titanium (IV) oxide photocatalysts, which can be applied for the degradation of organic pollutants not susceptible to biodegradation. A particularly important aspect of the work was the development of preparation method of nanocomposites with the magnetic core-shell and photocatalyst shell (TiO2)...
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Propagation Characteristics of Partial Discharges in an Oil-Filled Power Transformer
PublicationPower transformers are among the most important assets in the power transmission and distribution grid. However, they suffer from degradation and possible faults causing major electrical and financial losses. Partial discharges (PDs) are used to identify the insulation health status and their degradation level. PDs are incipient, low-magnitude faults caused by localized dielectric breakdown. Those activities emit signals in many...
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Stone cutting industry waste-supported zinc oxide nanostructures for ultrasonic assisted decomposition of an anti-inflammatory non-steroidal pharmaceutical compound
PublicationPowdered stone waste (PSW) obtained from a stone cutting industrial unit was applied as support for the immobilization of nano-sized ZnO to be utilized as an effective catalyst for the catalytic conversion of acetaminophen (ACE) under ultrasonication. The incorporation of ZnO nanostructures into PSW structure enhanced the specific surface area and pore volume of the as-prepared nanocompound. The change in the value of zero point...
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Selected Problems of Transport in Port Towns – Tri-City as an Example
PublicationPort towns are strategic places from the point of view of transport systems. They form integration junctions for various transport branches , apart from the traditional - road and railway ones , also for water( sea) transport which is active there. Moreover, air transport comes also into consideration , whose efficient functioning must be connected with good accessibility, that concerns sea transport as well. Efficient and...
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MnxCo3-xO4 spinel oxides as efficient oxygen evolution reaction catalysts in alkaline media
PublicationThe design of efficient electrocatalysts for oxygen evolution reaction (OER) is an essential task in developing sustainable water splitting technology for the production of hydrogen. In this work, manganese cobalt spinel oxides with a general formula of MnxCo3-xO4 (x=0, 0.5, 1, 1.5, 2) were synthesised via a soft chemistry method. Non-equilibrium mixed powder compositions were produced, resulting in high electrocatalytic activity....
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Semantic Driven Table Understanding in Born-Digital Documents
PublicationThis paper presents a new approach to table understanding, suitable for born-digital PDF documents. Advance beyond the current state of the art in table understanding is provided by the proposed reverse MVC method, which takes advantage of only partial logic structure loss (degradation) in born-digital PDF documents, as opposed to unrecoverable loss (deterioration) taking place in scan based PDF documents.
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Effect of long term service at elevated temperatures on mechanical properties of Manaurite XM reformer tubes
PublicationMicrostructure transformations occur in the Manaurite XM cast steel tubes during long-term operation in the reformer furnace were revealed and described. The rela tionship between mechanical properties, an increase of internal diameter of the tube and microstructure degradation is discussed. Static tensile test was performed on two types of samples with different shapes. It has been shown differences in the results of tests...
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Thermogravimetric analysis/ pyrolysis of used tyres and waste rubber
PublicationThe process of pyrolysis is investigated in this paper. The pyrolysis results of two samples: waste tyres and rubber at different heating rates (10, 20, 50 K/min), were compared. In other experiments the degradation of two pyrolysis products, char and oil was examined. The kinetic study using the thermogravimetry equipment (TG) was done, which allowed determination of the kinetic mechanism of the process. The elemental analysis...
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Fluorine ions in photocatalysts’ synthesis: an obstacle or an ally? The investigation of photocatalysts in Ti-O-F system
PublicationTitanium(IV) oxide (TiO2) is one of the most promising photocatalysts, which is expected to be applied in the photocatalytic degradation of xenobiotics. For sustainable development and green chemistry approach recently, much effort has been paid to enhance TiO2 photocatalytic activity in UV-vis light by modifying its structure. The photocatalytic process’s complexity cannot be simply described as electron-hole pairs generations...
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Unlocking the Secrets of River Pollution: Analyzing Organic Pollutants in Sediments—Experimental Study
PublicationUntreated wastewater released into rivers can result in water pollution, the spread of waterborne diseases, harm to ecosystems, contamination of soil and groundwater, as well as air pollution and respiratory problems for nearby humans and animals due to the release of greenhouse gases. The current study aims to investigate the recent input of anthropogenic loads into the rivers using linear alkylbenzene (LAB), which is one of the...
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Mono- and bimetallic (Pt/Cu) titanium(IV) oxide core–shell photocatalysts with UV/Vis light activity and magnetic separability
PublicationTitanium(IV) oxide is one of the most widely investigated photocatalysts. However, separation of nano-sized particulate titania might result in profitless technologies for commercial applications. Additionally, bare titania is almost inactive under the Vis range of solar spectrum due to its wide bandgap. Therefore, the present study aims to prepare novel coreinterlayer- shell TiO2 magnetic photocatalysts modified with metal nanoparticles...
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The shallow sea experiment with usage of linear hydrophone array
PublicationPurpose of this article is to present designed and made linear hydrophone array and the results obtained during in situ trails on Gulf of Gdańsk. The measuring system allowed to localize hydrophones in the selected points and perform measurements in both the horizontal antenna positioning and vertical. Made in this way recordings allow creating accurate 3D imaging of sound intensity/propagation. During research three floating objects...