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Measuring the density of DNA films using ultraviolet-visible interferometry
PublicationIn order to determine a proper value for the density of dry DNA films we have used a method based upon the measurement of interference effects in transmission spectra of thin DNA layers. Our results show that the methodology is effective and the density of DNA in this state, 1.407 g/cm3, is much lower than the commonly used 1.7 g/cm3. Obtaining accurate values for the DNA film density will allow the optical constants for DNA to...
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Reliable Multi-Stage Optimization of Antennas for Multiple Performance Figures in Highly-Dimensional Parameter Spaces
PublicationDesign of modern antenna structures needs to account for multiple performance figures and geometrical constraints. Fulfillment of these calls for the development of complex topologies described by a large number of parameters. EM-driven tuning of such designs is mandatory yet immensely challenging. In this letter, a new framework for multi-stage design optimization of multi-dimensional antennas with respect to several performance...
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EVOLUTIONARY MULTI–OBJECTIVE WEATHER ROUTING OF SAILBOATS
PublicationThe paper presents a multi-objective method, which optimises the route of a sailboat. The presented method makes use of an evolutionary multi-objective (EMO) algorithm, which performs the optimisation according to three objective functions: total passage time, a sum of all course alterations made during the voyage and the average angle of heel. The last two of the objective functions reflect the navigator’s and passenger’s comfort,...
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Improved Performance of 1-Ethyl-3-Methylimidazolium Tetrafluoroborate at Steel/HCl Interface by Iodide Ions
PublicationThe corrosion and corrosion inhibition of St37 steel in 0.1 M HCl solution by 1-ethyl-3-methylimidazolium tetrafluoroborate (EMITFB) and the effect of addition of KI on the inhibitive performance of EMITFB have been examined by electrochemical [electrochemical impedance spectroscopy, potentiodynamic polarization, and dynamic electrochemical impedance spectroscopy (DEIS)] and surface examination [scanning electron microscope (SEM)...
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β-cyclodextrin-containing polymer based on renewable cellulose resources for effective removal of ionic and non-ionic toxic organic pollutants from water
PublicationA novel, bio-derived cyclodextrin-based trifunctional adsorbent has been successfully synthesized for efficient, rapid and simultaneous removal of a broad-spectrum of toxic ionic (anionic and cationic dyes) and non-ionic organic pollutants from water. The composition, morphology and the presence of functional groups in the obtained sorption material were characterized by elemental analysis, XRD, SEM, and FTIR spectroscopy. The...
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The comparison of antioxidant properties and nutrigenomic redox-related activities of vitamin C, C-vitamers, and other common ascorbic acid derivatives
PublicationThe term ‘vitamin C’ describes a group of compounds with antiscorbutic activity of L-ascorbic acid (AA). Despite AA’s omnipresence in plant-derived foods, its derivatives have also been successfully implemented in the food industry as antioxidants, including the D-isomers, which lack vitamin C activity. This study aimed to determine the relationship between redox-related activities for five derivatives of AA using electrochemical,...
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COMPARISON OF HEAT TRANSFER CHARACTERISTICS IN SURFACE COOLING WITH BOILING MICROJETS OF WATER, ETHANOL AND HFE7100
PublicationThe basis of microjet technology is to produce laminar jets which when impinging the surface have a very high kinetic energy at the stagnation point. Boundary layer is not formed in those conditions, while the area of film cooling has a very high turbulence resulting from a very high heat transfer coefficient. Applied technology of jet production can result with the size of jets ranging from 20 to 500μm in breadth and 20 to 100μm...
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Homoisocitrate dehydrogenase from Candida albicans: properties, inhibition, and targeting by an antifungal pro-drug
PublicationThe LYS12 gene from Candida albicans, coding for homoisocitrate dehydrogenase was cloned and expressed as a His-tagged protein in Escherichia coli. The purified gene product catalyzes the Mg2+- and K+-dependent oxidative decarboxylation of homoisocitrate to alpha-ketoadipate. The recombinant enzyme demonstrates strict specificity for homoisocitrate. SDS-PAGE of CaHIcDH revealed its molecular mass of 42.6±1 kDa, while in size-exclusion...
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Chemical and biological evaluation of antioxidant activity of endogenous redox-active compounds compared to plant-derived exogenous antioxidants
PublicationThe research conducted so far has shown that endogenous antioxidants, despite being regarded as the first line of antioxidant defense, may not be sufficient to maintain redox homeostasis in cells exposed to oxidative stress. The results obtained in the doctoral dissertation show that endogenous redox-active compounds were moderate or weak scavengers of ABTS and DPPH radicals, while in cellular setting, their impact on the reducing...
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Key issues in modeling and optimization of lignocellulosic biomass fermentative conversion to gaseous biofuels
PublicationThe industrial-scale production of lignocellulosic-based biofuels from biomass is expected to benefit society and the environment. The main pathways of residues processing include advanced hydrolysis and fermentation, pyrolysis, gasification, chemical synthesis and biological processes. The products of such treatment are second generation biofuels. The degree of fermentation of organic substances depends primarily on their composition...
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Waveform design for fast clutter cancellation in noise radars
PublicationCanceling clutter is an important, but computation-ally intensive part of signal processing in noise radars. It is shown that considerable improvements can be made to a simple least squares canceler if minor constraints are imposed onto noise waveform. The proposed scheme is potentially capable of canceling clutter in real-time, even for high sampling rates.
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Strategie miast powiatowych na obszarze peryferyjnym województwa pomorskiego.
PublicationArtykuł nawiązuje do badań problemów rozwoju obszarów peryferyjnych (czyli poza obszarami metropolitalnymi) prowadzonych przez autora od 2009 r. Postawił on hipotezę, że rozwój miast powiatowych może zaktywizować gospodarczo ich otoczenie. W 2013 r. zbadał czynniki rozwojowe wskazane w planach strategicznych miast powiatowych na obszarze peryferyjnym województwa pomorskiego, obecnie - strategie tych miast w części dotyczącej rozwoju...
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Novel analysis methods of dynamic properties for vehicle pantographs
PublicationTransmission of electrical energy from a catenary system to traction units must be safe and reliable especially for high speed trains. Modern pantographs have to meet these requirements. Pantographs are subjected to several forces acting on their structural elements. These forces come from pantograph drive, inertia forces, aerodynamic effects, vibration of traction units etc. Modern approach to static and dynamic analysis should...
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Analysis of the design development of the sliding table saw spindles
PublicationProducers of sliding table saws constantly strive for improvement in sawing accuracy. One of the method is an upswing in a spindle behavior, since, it affects to a large degree sawing effects. The design development of sliding table saw spindles during the last quarter-century is presented. The spindle system of the modernized spindle of the sawing machine Fx550 is described.
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Elctrochemical oxidation and corrosion resistance of the Ti13Nb13Zr alloy
PublicationThis paper presents the results of oxidation and corrosion tests carried out on titanium alloy Ti13Nb13Zr. The oxide film was prepared by electrochemical environment 2M H3PO4 for 30 min and 1 h, at a constant voltage 40V. The tests of corrosion resistance were performed by potentiostatic method in Ringer's solution at different pH values: 7, 5 and 3. The change in an appearance of surface and the increase in corrosion resistance...
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Web component for automatic extraction of ontological information from informal description of web services
PublicationThis article treats about usage possibilities of Web Services and cooperation in development that leads to constant improvement of these components. It describes the semantic methods which can beused to create the description that is comprehensible for computers. It also presents the two models supporting the automatic generation of the semantic description based on informal description. Thepaper draws upon the comparison of two...
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Who makes Europe
Publication"Obrzeża" seria obrazów Obrzeża to kompozycja złożona z obrazów akwarelowych, połączonych w poziomą linię o wysokości 10 cm, która narasta etapami, ciągle powiększając się. Jest to dość przewrotna opowieść o miejscach, bazująca na subiektywnej selekcji motywów przedstawionych za pomocą realistycznych odwzorowań zestawionych na zasadzie dyptyku z ich abstrakcyjnymi kontrapunktami.
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On the synthesis of coupled-lossy resonator filters with unloaded quality factor control
PublicationA technique for fast synthesis of coupling matrix low-pass prototypes of generalized Chebyshev bandpass filters with lossy resonators is presented in this paper. The coupling matrix is found by solving a nonlinear least squares problem based on zeros and poles of filter's transfer functions. Additional constraints are introduced that allow one to control the level of unloaded quality factor of resonators.
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Local and global response of sandwich beams made of GFRP facings and PET foam core in three point bending test
PublicationIn the paper behaviour of laminated sandwich beams (FRP face sheet – PET foam core – FRP face sheet) subjected to three point bending is studied. The paper aim is to find practical descriptions enabling effective and accurate estimation of the elastic response, damage and failure of the beams, basing on experiments and static calculations. Therefore a number of tests are described, that were done on laminated coupons and foam specimens...
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HYDROGEN PRODUCTION PERFORMANCE IN THERMOCATALYTIC REACTOR BASED ON THE INTERMETALLIC PHASE OF NI3AL
PublicationThe main aim of the following paper is mathematical modelling for momentum, heat and mass transfer, which is accompanied by chemical surface reactions of the flow of the mixture helium and methanol. The thermocatalytic devices used for decomposition of hydrocarbons incorporate vertical microchannels coupling at the ends and heated to 500 oC at the walls. The results of the experiment were compared with CFD calculations to calibrate...
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Comparison of the exponential thermal transient parameterization methods with the SMTP method in the unipedicled DIEP flap computer modelling and simulation
PublicationThe aim of this paper is to compare the spatial contrast of the image descriptors obtained via three different thermal transient parameterization methods in Active Dynamic Thermography. The thermal constants and amplitude values of the one- and two- exponential parametrization are compared to the Simplified Magnitude-Temporal Parametrization method (SMTP). The comparison is performed using the data obtained by simulating the cold...
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A study of concentration depolarization and quenching of photoluminescence of solutions
PublicationThe concentration-dependence of emission anisotropy r/r0 and quantum yield eta/eta0 of the photoluminescence of glycerol-water solutions of rhodamine B in two systems of viscosities 7.4 P and 0.72 P is investigated. The experimental data are compared with the new theory of concentraticn depolarization (J. Lumin., 5, 413 (1972)) and concentration quenching of photoluminescence (Acta Phys. Hungar., 30, 145 (1972)), which takes...
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Physical and Thermophysical Properties of 1-Hexyl-1,4-diaza[2.2.2]bicyclooctanium Bis(trifluoromethylsulfonyl)imide Ionic Liquid
PublicationOwing to their unique properties, ionic liquids (ILs) have become a real alternative to organic compounds. Nowadays, ILs are commonly used in a number of areas such as chemical synthesis and separation techniques. However, ionic liquids continue to have a limited applicability in industry because the information on their physical and chemical properties is not readily available. This paper presents, for the first time, the results...
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A novel heterogeneous model of concrete for numerical modelling of ground penetrating radar
PublicationThe ground penetrating radar (GPR) method has increasingly been applied in the non-destructive testing of reinforced concrete structures. The most common approach to the modelling of radar waves is to consider concrete as a homogeneous material. This paper proposes a novel, heterogeneous, numerical model of concrete for exhaustive interpretation of GPR data. An algorithm for determining the substitute values of the material constants...
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The Use of an Autoencoder in the Problem of Shepherding
PublicationThis paper refers to the problem of shepherding clusters of passive agents consisting of a large number of objects by a team of active agents. The problem of shepherding and the difficulties that arise with the increasing number of data describing the location of agents have been described. Several methods for reducing the dimensionality of data are presented. Selected autoencoding method using a Restricted Boltzmann Machine is...
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Two-criteria optimisation problem for ventral hernia repair
PublicationTwo-criteria optimisation problem related to laparoscopic ventral hernia repair is formulated in this paper. An optimal implant from a given set and its orientation is sought. The implant is subjected to kinematic extortions due to a patient’s body movement and intra-abdominal pressure. The first criterion of the optimisation problem deals with the reaction force in the implant fastener, while the deflection of the implant constitutes...
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Big Data Processing by Volunteer Computing Supported by Intelligent Agents
PublicationIn this paper, volunteer computing systems have been proposed for big data processing. Moreover, intelligent agents have been developed to efficiency improvement of a grid middleware layer. In consequence, an intelligent volunteer grid has been equipped with agents that belong to five sets. The first one consists of some user tasks. Furthermore, two kinds of semi-intelligent tasks have been introduced to implement a middleware...
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Designing a ship course controller by applying the adaptivebackstepping method
PublicationThe article discusses the problem of designing a proper and efficient adaptive course-keeping control system for a seagoingship based on the adaptive backstepping method. The proposed controller in the design stage takes into account thedynamic properties of the steering gear and the full nonlinear static maneuvering characteristic. The adjustable parametersof the achieved nonlinear control structure were tuned up by using the...
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Thermodynamic interpretation and prediction of CO2 solubility in imidazolium ionic liquids based on regular solution theory
PublicationRegular solution theory (RST) is the most popular model for the interpretation of the interaction between CO2 and ionic liquids. In the present work, the parameters of this model were determined for the CO2 absorption in eleven imidazolium ionic liquids. The y-intercept (A) of the RST model for the investigated imidazolium liquids increases with increasing temperature whereas the slope (B) remains constant. The values of RST parameters...
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The Influence of the Depth of Cut in Single-Pass Grinding on the Microstructure and Properties of the C45 Steel Surface Layer
PublicationThe paper contains the results of a metallographic examination and nanoindentation test conducted for the medium carbon structural steel with low content of Mn, Si, Cu, Cr, and Ni after its grinding to a depth ranging from 2 μm to 20 μm, at constant cutting speed (peripheral speed) of vs = 25 ms−1 and constant feed rate of vft = 1 m/min. Applied grinding parameters did not cause the surface layer hardening, which could generate...
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Degradation of ferritic X10CrAlSi18 stainless steel caused by slurry
PublicationThe slurry erosion tests of ferritic X10CrAlSi18 steel were carried out using a slurry pot device. In order to investigate the erosion process, two series of tests were performed: first one with a constant impact velocity of 5 m/s, 7 m/s and 9 m/s and the second one, during which the impact velocity was changed after every exposure. During each test, an influence of test conditions on volume loss, surface hardness and roughness...
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Thermal and economic investigation of straight and U-bend double tube heat exchanger with coiled wire turbulator
PublicationExperimental research has been carried out for four individual heat exchanger constructions, i.e., plain double tube, turbulized double tube, plain U-bend and U-bend with turbulator. Tests were made for the water-water system. The study covered a wide measuring range, i.e., Re = 800–9000 – on the shell side, for a constant cold water temperature of 9 ◦C and hot water of 50 ◦C. The heat exchangers were made from copper tubes with...
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Modelling and Simulation of a New Variable Stiffness Holder for Milling of Flexible Details
PublicationModern industry expectations in terms of milling operations often demand the milling of the flexible details by using slender ball-end tools. This is a difficult task because of possible vibration occurrence. Due to existence of certain conditions (small depths of cutting, regeneration phenomena), cutting process may become unstable and self-excited chatter vibration may appear. Frequency of the chatter vibration is close to dominant...
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Influence of electrode geometric arrangement on the operation of narrow circular electrostatic precipitator
PublicationIn this work the influence of electrode geometric arrangement on the operation of a circular electrostatic precipitator (ESP) was investigated using Particle Image Velocimetry (PIV) method. The ESP was a glass circular cylinder (29 mm in diameter, 300 mm long) equipped with a wire discharge electrode and circular-cylinder collecting electrode. The stainless-steel discharge wire electrode (0.23 mm in diameter, 100 mm long) was mounted...
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Numerical simulation of temperature distribution of heat flow on reservoir tanks connected in a series
PublicationThe flow of temperature distribution through a medium in thermodynamic studies plays an important role in understanding physical phenomena in chemical science and petroleum engineering, while temperature distribution indicates the degree of reaction that must be undergone to obtain the final product. Therefore, this paper aims to present and apply the exponential matrix algorithm (EMA), differential transformation algorithm (DTA),...
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Theoretical and experimental analysis of guided wave propagation in plate-like structures with sinusoidal thickness variations
PublicationGuided waves have attracted significant attention for non-destructive testing (NDT) and structural health monitoring (SHM) due to their ability to travel relatively long distances without significant energy loss combined with their sensitivity to even small defects. Therefore, they are commonly used in damage detection and localization applications. The main idea of incorporating guided waves in NDT and SHM is based on processing...
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Determination of stepped plate thickness distribution using guided waves and compressed sensing approach
PublicationGuided waves recently have attracted significant interest as a very promising research area. The signals registered by a specially designed sensor network are processed to assess the state of the tested structure. Despite the constant development of novel damage detection algorithms employing guided waves, the phenomenon of wave propagation still needs detailed recognizing and understanding for the further progress of non-destructive...
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Constrained aerodynamic shape optimization using neural networks and sequential sampling
PublicationAerodynamic shape optimization (ASO) involves computational fluid dynamics (CFD)-based search for an optimal aerodynamic shape such as airfoils and wings. Gradient-based optimization (GBO) with adjoints can be used efficiently to solve ASO problems with many design variables, but problems with many constraints can still be challenging. The recently created efficient global optimization algorithm with neural network (NN)-based prediction...
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Supervised model predictive control of wastewater treatment plant
PublicationAn optimizing control of a wastewater treatment plant (WWTP), allowing for cost savings over long time period and fulfilling effluent discharge limits at the same time, requires application of advanced control techniques. Model Predictive Control (MPC) is a very suitable control technology for a synthesis of such a truly multivariable controller that can handle constraints and accommodate model-based knowledge combined with hard...
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Influence of Gd deposition on the oxidation behavior and electrical properties of a layered system consisting of Crofer 22 APU and MnCo2O4 spinel
PublicationIn the study, the surface of the Crofer 22APU ferritic steel was modified with gadolinium oxide nanoparticles and a protective-conducting layer consisting of the MnCo2O4 spinel. This system was studied in the context of application in IT-SOFC interconnects. Four types of samples were studied: unmodified steel, steel coated with a manganese-cobalt spinel layer, steel modified with gadolinium oxide nanoparticles, and a system consisting...
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Multisine impedimetric monitoring with an in-depth distribution of relaxation times analysis of WE43 and AZ31 magnesium alloys corrosion
PublicationThis research aims to develop and utilize an impedance-based tool for monitoring non-stationary electrochemical processes, coupling the multisinusoidal perturbation signal approach and distribution of relaxation times (DRT) analysis for the first time. The approach was used to distinguish independent processes occurring at the surface of AZ31 and WE43 Mg alloys undergoing corrosion in Hank’s Balanced Salt Solution at 37 °C. We...
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Photophysics of Ru(II) Dyads Derived from Pyrenyl-Substitued Imidazo[4,5-f][1,10]phenanthroline Ligands.
PublicationThe photophysics of a series of Ru(II) dyads based on the 2-(1-pyrenyl)-1H-imidazo[4,5-f][1,10]-phenanthroline ligand was investigated. The ability of these metal complexes to intercalate DNA and induce cell death upon photoactivation makes them attractive photosensitizers for a range of photobiological applications, including photodynamic therapy. In the present study, time-resolved transient absorption and emission spectroscopy...
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Optically transparent boron-doped nanocrystalline diamond films for spectroelectrochemical measurements on different substrates
PublicationFabrication process of optically transparent boron nanocrystalline diamond (BNCD) electrode on silicon and quartz substrate was shown. The B-NCD films were deposited on the substrates using Microwave Plasma Assisted Chemical Vapor Deposition (MWPACVD) at glass substrate temperature of 475 ºC. A homogenous, continuous and polycrystalline surface morphology with high sp3 content in B-NCD films and film thickness depending from substrate...
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Removal of nonsteroidal anti-inflammatory drugs and analgesics from wastewater by adsorption on cross-linked β-cyclodextrin
PublicationWe present a method using the material in the form of cross-linked β-cyclodextrin (CD) showing high efficiency in the simultaneous removal of hazardous pollutants from sewage, such as diclofenac (DIC), ibuprofen (IBU), ketoprofen (KETO), naproxen (NAPR), salicylic acid (SALI) and tramadol (TRAM). The material is stable and particularly easy to regenerate. The sorbent probably remembers the shape of the contaminants, which increases...
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Scheduling of compatible jobs on parallel machines
PublicationThe dissertation discusses the problems of scheduling compatible jobs on parallel machines. Some jobs are incompatible, which is modeled as a binary relation on the set of jobs; the relation is often modeled by an incompatibility graph. We consider two models of machines. The first model, more emphasized in the thesis, is a classical model of scheduling, where each machine does one job at time. The second one is a model of p-batching...
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Właściwości niskotemperaturowe betonów asfaltowych o wysokim module sztywności (AC-WMS) w badaniach trzypunktowego zginania
PublicationArtykuł przedstawia właściwości niskotemperaturowe betonów asfaltowych o wysokim module sztywności. Przedstawione wyniki zostały uzyskane w dwóch badaniach zginania trzypunktowego próbek belkowych: ze stałą prędkością przemieszczenia oraz pod stałym obciążeniem. Obie te metody są od dawna stosowane na Politechnice Gdańskiej do oceny właściwości niskotemperaturowych betonów asfaltowych. Badaniu poddano pięć betonów asfaltowych –...
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Fuzzy Control of Waves Generation in a Towing Tank
PublicationThis paper presents the results of research related to the transformation of electrical energy into potential and kinetic energy of waves generated on the water surface. The waves are generated to model the environmental conditions for the needs of the model tests. The model tests are performed on model-scale objects to predict the features of full-scale maritime objects. It is done to improve human safety and the survivability...
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Combining Computational Fluid Dynamics with a Biokinetic Model for Predicting Ammonia and Phosphate Behavior in Aeration Tanks
PublicationThe aim of this study was to use computational fluid dynamics for predicting the behavior of reactive pollutants (ammonia and phosphate) in the aerobic zone of the bioreactor located at the Wschod wastewater treatment plant in Gdansk, Poland. The one-dimensional advection-dispersion equation was combined with simple biokinetic models incorporating the Monod-type expressions as source terms for the two pollutants. The problem was...
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Preliminary Testing of the Influence of Modified Polycaprolactones on Anabaena Variabilis Growth in Seawater
PublicationSeveral new biodegradable polymer materials have recently come onto the global market. Mostly the results on degradation kinetic studies are presented. This paper suggests using one of the tests to estimate the impact of polymer packaging material on sea life. The microorganism chosen was Anabaena variabilis (identified in many waters, including those of the Baltic Sea, especially in the Gulf of Gdansk and Puck Bay; this cyanobacterium...
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Interactions of telomeric proteins with nucleic acids: sequence recognition on intact and oxidatively damaged telomeres
PublicationTelomeres are complex nucleoprotein assemblies that play a vital role in the maintenance of functional ends of linear chromosomes. Telomeric DNA, composed of tandem repeats of the 5'-TTAGGG-3' motif, solves the so-called end replication problem: as chromosomes shorten with each cell division, no information is lost, and the telomere can be re-extended. In the cell, many protein factors regulate telomere length, nuclear positioning...