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The efficiency and reliability of pollutant removal in a hybrid constructed wetland with giant miscanthus and Jerusalem artichoke in Poland
PublicationIn this paper, we analysed the pollutant removal efficiency and reliability of a vertical and horizontal flow hybrid constructed wetland (CW) planted with giant miscanthus and Jerusalem artichoke. The wastewater treatment plant, located in south-eastern Poland, treated domestic sewage at an average flow rate of 1.2m3·d−1. The tests were carried out during. 5-years of operation of the sewage treatment plant (2011–2016). During this...
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A newly-developed model for predicting cutting power during wood sawing with circular saw blades
PublicationIn the classical approach, cutting forces and cutting power in sawing processes of orthotropic materials such as wood are generally calculated on the basis of the specific cutting resistance kc (cutting force per unit area of cut). For every type of sawing kinematics (frame saws, band saws and circular sawing machines) different empirical values of specific cutting resistance kc have to be applied. It should be emphasised that...
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Investigation of behaviour of metal structures with polymer dampers under dynamic loads
PublicationA large number of accidents concerning structures subjected to dynamic loads have been recently observed. One of the examples of such a structure is a temporary steel grandstand erected using scaffolding system. Dynamic load that is generated by crowd movement has a significant influence on the behaviour of the structure and may lead to excessive structural vibrations. The aim of the study is to consider the idea of using polymer...
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Influence of Added Water Mass on Ship Structure Vibration Parameters in Virtual and Real Conditions
PublicationModelling of ship structures in a virtual environment is now standard practice. Unfortunately, many engineers forget to consideri the influence of added water on the frequency values and the amplitude of natural vibrations. The article presents the effect of water damping on the frequency values of the individual natural vibration modes. The tests were carried out in two stages. First, the mentioned values were determined using...
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The influence of SVC on the progress of voltage collapse
PublicationThe article presents the simulation concerning the cooperation of SVC circuit with a generative set in time, when of power system reaches low values which may lead to the fall-out of generator from the synchronous operation.
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Możliwości sterowania mocą bierną elektrowni wiatrowej : Reactive power control methods in wind parks
PublicationReferat poświęcony jest zagadnieniu sterowania mocą bierną w elektrowniach wiatrowych. W pierwszej części referatu opisano tło problemu sterowania mocą bierną w parkach wiatrowych, podano powody, dla których moc bierna powinna podlegać regulacji oraz zarysowano metody, które mogą być do niej użyte. W celu sprawdzenia proponowanych metod kompensacji, zbudowano model matematyczny elektrowni wiatrowej, którego poszczególne elementy...
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Experiments and Analysis of the Limit Stresses of a Magnetorheological Fluid
PublicationPaper presents the results of a rheological test of a commercial magnetorheological (MR) fluid (MRF-132DG). The researchincludes the problem of measuring and interpreting limit stresses under conditions close to the magnetic saturation of the fluid. Fourdifferent limit stresses were determined, two related to the yield point and two related to the flow point. Methods for determining limitstresses, especially due to excitation...
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Fluorescence of p-hydroxyazobenzocrowns – Tautomeric equilibrium effect
PublicationThe spectroscopic properties of a series of para-hydroxyazobenzocrowns, including three novel compounds, were investigated using UV–Vis absorption and emission spectroscopy. This study presents, for the first time, determined quantum yield (QY) values for macrocycles of this category, ranging between 0.122 and 0.195. The highest values were obtained for crowns bearing two phenyl substituents in benzene rings. The impact of aromatic...
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Experiment-aided virtual prototyping to minimize tool-workpiece vibration during boring of large-sized structures
PublicationThe paper presents the author's method of solving the problems of vi-bration suppression during boring of large-sized workpieces by means of an in-novative method of adjusting the rotational speed of the boring bar. It consists in selecting the spindle speed in accordance with the results of the cutting process simulation. The method includes identification of the model of the finite element method of the boring bar. The Root Mean...
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Analysis of Lombard speech using parameterization and the objective quality indicators in noise conditions
PublicationThe aim of the work is to analyze Lombard speech effect in recordings and then modify the speech signal in order to obtain an increase in the improvement of objective speech quality indicators after mixing the useful signal with noise or with an interfering signal. The modifications made to the signal are based on the characteristics of the Lombard speech, and in particular on the effect of increasing the fundamental frequency...
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Kinetics of Cross-Linking Reaction of Epoxy Resin with Hydroxyapatite-Functionalized Layered Double Hydroxides
PublicationThe cure kinetics analysis of thermoset polymer composites gives useful information about their properties. In this work, two types of layered double hydroxide (LDH) consisting of Mg2+ and Zn2+ as divalent metal ions and CO32− as an anion intercalating agent were synthesized and functionalized with hydroxyapatite (HA) to make a potential thermal resistant nanocomposite. The curing potential of the synthesized nanoplatelets in the...
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Possibility of thermal imaging use in studies of natural convection heat transfer on the example of an isothermal vertical plate.
PublicationA new method of infrared (IR) camera use in convective heat transfer studies has been presented. Until now, IR cameras were utilized for temperature field visualizations of flat heated surfaces of solid objects only. Because liquids and gasses do not emit radiation in the infrared range of wave lengths, detection of temperature field in the air was conducted with the use of plastic mesh, which, after heating by hot air, emits infrared...
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Proportional-Derivative and Model-Based Controllers for Control of a Variable Mass Manipulator
PublicationIn the paper, numerical analysis of dynamics of a variable mass manipulator is presented. A revolute joints composed manipulator is considered. Payload of the gripper is considered as the only element characterized by unknown value of its mass (variable between subsequent operations). As in other cases of the revolute joints composed manipulators, its behaviour dependents significantly on the pose of the manipulator. When the manipulator...
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Static electric multipole susceptibilities of the relativistic hydrogenlike atom in the ground state: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function
PublicationThe ground state of the Dirac one-electron atom, placed in a weak, static electric field of definite $2^{L}$ polarity, is studied within the framework of the first-order perturbation theory. The Sturmian expansion of the generalized Dirac-Coulomb Green function [R. Szmytkowski, J. Phys. B: At. Mol. Opt. Phys. 30, 825 (1997); erratum R. Szmytkowski, J. Phys. B: At. Mol. Opt. Phys. 30, 2747 (1997)] is used to derive closed-form analytical...
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Structural, magnetic and spectral properties of tetrahedral cobalt(II) silanethiolates: a variety of structures and manifestation of field-induced slow magnetic relaxation
PublicationBlue crystals of five heteroleptic cobalt(II) silanethiolates 1–5 have been obtained by the reaction of [Co{SSi (tBuO)3}2(NH3)]2 with aminopyridines and aminomethylpyridines at an appropriate molar ratio and their structural, spectral, thermal and magnetic properties have been established and described. All complexes 1–5 contain Co(II) ions in a tetrahedral CoN2S2 environment formed by (tBuO)3SiS− residues and pyridines and present...
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Health System Efficiency in European Countries: Network Data Envelopment Analysis Approach
PublicationPurpose: The article's main aim is to investigate the effectiveness of health systems in European countries based on EUROSTAT data. A comparative analysis of the health systems' effectiveness in different countries is based on their improvement (reform), using the best practices approach. Design/Methodology/Approach: The network DEA model and a slack-based model (NDEA – SBM) are used. A non-oriented model is used. The research...
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Designing acoustic scattering elements using machine learning methods
PublicationIn the process of the design and correction of room acoustic properties, it is often necessary to select the appropriate type of acoustic treatment devices and make decisions regarding their size, geometry, and location of the devices inside the room under the treatment process. The goal of this doctoral dissertation is to develop and validate a mathematical model that allows predicting the effects of the application of the scattering...
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A ship domain-based model of collision risk for near-miss detection and Collision Alert Systems
PublicationThe paper presents a new model of ship collision risk, which utilises a ship domain concept and the related domain-based collision risk parameters. An encounter is here described by five variables representing: degree of domain violation (DDV), relative speed of the two vessels, combination of the vessels’ courses, arena violations and encounter complexity. As for the first three variables, their values can be directly computed...
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Density, sound velocity, viscosity, and refractive index of new morpholinium ionic liquids with amino acid-based anions: Effect of temperature, alkyl chain length, and anion
PublicationIn this work, room temperature synthesis of twenty new ionic liquids (ILs) based on the N-alkyl-N-methylmorpholinium ([Mor1,R], R = 2, 3, 4, 6, 8) cation and N-acetyl-L-amino acid anions (L-alaninate, L-valinate, L-leucinate, L-isoleucinate) was described. The synthesized ILs were characterized by various spectroscopic techniques and high-resolution mass spectrometry. Furthermore, density (ρ), sound velocity (v), viscosity (η)...
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Solvation of ionic liquids based on N-methyl-N-alkyl morpholinium cations in dimethylsulfoxide – volumetric and compressibility studies
PublicationThe density and sound velocity of the solutions of ionic liquids based on N-alkyl-N-methyl-morpholinium cations, N-ethyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide, N-butyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide, N-methyl-N-octyl-morpholinium bis(trifluoromethanesulfonyl)imide and N-decyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide in dimethylsulfoxide were measured at T = (298.15 to 318.15)...
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Entropic Measures of Complexity of Short-Term Dynamics of Nocturnal Heartbeats in an Aging Population
PublicationTwo entropy-based approaches are investigated to study patterns describing differences in time intervals between consecutive heartbeats. The first method explores matrices arising from networks of transitions constructed following events represented by a time series. The second method considers distributions of ordinal patterns of length three, whereby patterns with repeated values are counted as different patterns. Both methods provide...
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Selected properties and parameters of radio channel impulse response estimation in ISM 2.4 GHz band
PublicationThe article presents experimental research indicating that the impulse response of the communication channel, determined in practice, are not of an universal character, but only represent its approximate value for the frequency on which this measurement was made. Phases for each of the replicas of the measurement signal were determined during the analysis of the received signals in the baseband. Phase changes of individual replicas...
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Analysis of magnetic field of Helmholtz's coils
PublicationThe 3-axis fluxgate magnetometer requires conducting a precise calibration in the magnetic field whose value is determined and which is characterized by the high uniformity of the distribution of the field, especially along the axis of the sensors. The generation of the magnetostatic field characterized by the high uniformity, can be achieved by using the Helmholtz's coils. The requirements of the uniformity of distribution of...
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An Approach to Mean Path Loss Model Estimation for Off-Body Channels
PublicationThis paper presents an approach to estimation of the mean path loss model parameters in off-body Body Area Networks channels. In this approach, the path loss exponent is constrained to a value obtained for the line-of-sight (LoS) propagation in the co-polarised channel, considering a generalised static scenario. The comparison of the goodness of fit between the proposed approach and other approaches, for a set of measurements obtained...
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Secondary emission influenced fluorescence decay of a homogeneous fluorophore solution
PublicationAn analytical expression is found allowing the calculation of the secondary emission influenced fluorescence decay of a homogeneous fluorophore solution. Before starting the calculation one has to know the shape of the primary fluorescence decay of the fluorophore and the value of the parameter kappa denoting the ratio of the secondary to primary steady-state fluorescence intensities. The method elaborated by Budo and Ketskemety...
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Scaling of numbers in residue arithmetic with the flexible selection of scaling factor
PublicationA scaling technique of numbers in resudue arithmetic with the flexible selection of the scaling factor is presented. The required scaling factor can be selected from the set of moduli products of the Residue Number System (RNS) base. By permutation of moduli of the number system base it is possible to create many auxilliary Mixed-Radix Systems associated with the given RNS with respect to the base, but they have different sets...
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Comparative analysis of balancing of V6 engines with common- and split-pin crankshafts
PublicationAn analysis of balancing of V6 engines equipped with split-pin crankshafts with any cylinder bank angle based on the mathematical relations derived in the paper was carried out. A comparison of the quality of their balancing with engines equipped with common-pin crankshafts was also carried out. The bank angle ranges beneficial for balancing of moments of inertia forces in reciprocating motion were determined. A mathematical relation...
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Fuzzy regresion approach to road safety analysis at regional level
PublicationRoad safety modelling on regional level of NUTS 2 in the EU is the complex issue and authors of this article indicate this in previous publications. NUTS 2 are basic regions for the application of regional policies (0.8-3 m inhabitants). During multivariate models development they discovered that it is difficult to make regression model well described all regions, even if they are from one country. In the first step Poisson model...
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Free randomness amplification using bipartite chain correlations
PublicationA direct analysis of the task of randomness amplification from Santha-Vazirani sources using the violation of the chained Bell inequality is performed in terms of the convex combination of no-signaling boxes required to simulate quantum violation of the inequality. This analysis is used to find the exact threshold value of the initial randomness parameter from which perfect randomness can be extracted in the asymptotic limit of...
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Minimum drag shape bodies moving in inviscid fluid - revisited
PublicationThis paper presents the classic approach to minimum drag shape body problem, moving at hypersonic speeds, leading to famous power law shapes with value of the exponent of 3/4. Two- and three-dimensional cases are considered. Furthermore, an exact pseudo solution is given and its uselessness is discussed. Two new solutions are introduced, namely an approximate solution due to form of the functional and solution by means of optimisation...
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A method for testing the wide-sense stationary uncorrelated scattering assumption fulfillment for an underwater acoustic channel
PublicationWide-sense stationary and uncorrelated scattering (WSSUS) assumptions are often applied for the statistical description of wireless communication channels. However, in the case of underwater acoustic channels the WSSUS model is of limited value. The degree of similarity of in-phase and quadrature components of the channel impulse response, measured with the use of bandpass modulated signals, can be used as an indicator of WSSUS...
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Optical Magnetometry Based on Nanodiamonds with Nitrogen-Vacancy Color Centers
PublicationNitrogen-vacancy color centers in diamond are a very promising medium for many sensing applications such as magnetometry and thermometry. In this work, we study nanodiamonds deposited from a suspension onto glass substrates. Fluorescence and optically detected magnetic resonance spectra recorded with the dried-out nanodiamond ensembles are presented and a suitable scheme for tracking the magnetic-field value using a continuous...
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Influence of Operation Conditions on Temperature Hazard of Lithium-Iron-Phosphate (LiFePO4) Cells
PublicationThe article presents and discusses the results of research on hazard, especially temperature, for selected lithium-ion-phosphate cells operated in accordance with the manufacturer’s recommendations but used under onerous mining conditions. This applies to the performance of cells in battery sets without the application of any management system (BMS). On the basis of the obtained test results, first of all, the influence of the...
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Method of determining the residual fluxes in transformer core
PublicationThe article presents the method of calculating the residual induction in transformer columns. The method is based on measurement of the magnetic induction in selected points around the transformer core. The values of residual induction are calculated as linear combination of the results of measurement.
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Rewitalizacja przestrzeni miejskiej poprzez wydarzenia i inicjatywy sportowe
PublicationArtykuł opisuje powiązania pomiędzy procesami rewitalizacji przestrzeni miejskiej, a wydarzeniami i inicjatywami sportowymi różnej skali i rangi. Można wyodrębnić trzy główne uwarunkowania występowania tych powiązań: 1) podczas organizacji największych wydarzeń sportowych o zasięgu globalnym, takich jak igrzyska olimpijskie oraz mistrzostwa Świata i Europy w piłce nożnej; 2) podczas przedsięwzięć aktywizujących mieszkańców w formie...
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The environmental dimension of city dwellers’ quality of life and the city’s social and spatial variability
PublicationThe purpose of this paper is to attempt an analysis of the environmental dimension of the quality of life using quantitative surveys conducted among residents of Gdańsk. In the paper, we make reference to the theoretical assumptions ensuing from the concept of a comprehensive and integrated approach to the development of the urban environment, whilst noting the profound impact humans bring to their evaluation of the environmental...
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Dynamic Analysis of the Turnout Diverging Track for HSR with Variable Curvature Sections
PublicationThe paper presents an analytical method of identifying the curvature of the turnout diverging track consisting of sections of varying curvature. Both linear and nonlinear (polynomial) curvatures of the turnout diverging track are identified and evaluated in the paper. The presented method is a universal one, it enables to assume curvature values at the beginning and end point of the geometrical layout of the turnout. The results...
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Evaluation of Ambient Air Odour Quality in Vicinity of Municipal Landfill Using Electronic Nose Technique
PublicationThe paper presents the results of investigation on ambient air quality evaluation with respect to concentration of odorants in a vicinity of municipal landfill. The investigation was carried out with a prototype of electronic nose and a team of panelists utilizing the Nasal Ranger field olfactometers. The prototype was equipped with a set of six semiconductor sensors by FIGARO Co. and one PID-type sensor. Performed measurements...
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The reduction of vibrations in circular sawing machines
PublicationThe presented in this paper the main objectives of the research were to explore vibrations signals of the main spindle system, the machine tool body and a circular saw to extract informative features for assessment of the designs of the panel saw Fx3 and its follower Fx550.Even though the main spindle of the new table sliding saw Fx550 has its rotational speeds larger about 20% in comparison to the Fx3, peak values of the vibrational...
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Preliminary studies on the effect of feed speed on the colour change of wood
PublicationThis paper presents the results of preliminary analyses of the effect of cutting parameters on changes in the colour of wood. Beech wood cut with use circular saw was analysed. The cutting parameter tested was the feed speed, represented by the feed per tooth. Sawing processes with different feed per tooth ranging from 0.0008 mm to 0.09 mm were analysed. It was observed that over the entire range of feed rate per tooth analysed,...
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Abundance and biomass of bacteria in two Arctic glacial fjords
PublicationTotal numbers and biomass of bacterioplankton in water in two glacial fjords off west Spitsbergen have been studied. Samples were collected from different water depth layers - from the surface to 80-90 m. Total bacterial number (TBN), biomass and morphological structure were determined by the acridine orange direct count method. The highest values of TBN and biomass in the water column were found on stations situated adjacent...
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Identyfikacja parametrów dynamicznych want mostu Rędzińskiego we Wrocławiu
Publicationthe paper presents results of dynamic analysis conducted on stay-cables of rędziński bridge in wrocław. identified in situ dynamic parameters (natural frequency and logarithmic decrement damping ratio) of selected stays were and compared to the values featured in the project.
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Reliability and types of diagnosis in the process of diesel engine operation
PublicationThe article presents complexity of the problem concerning development of diagnosis with defined reliability by a diagnosing system (SDG) on technical condition of marine combustion engines, especially main engines. It was shown that development of the final diagnosis, the so-called initial operation diagnosis, on the operational usability (fDG on PEx) of a main engine in particular, is not possible without prior development of...
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The relationship between standard reduction potentials of catechins and biological activities involved in redox control
PublicationRedox homeostasis involves factors that ensure proper function of cells. The excess reactive oxygen species (ROS) leads to oxidative stress and increased risk of oxidative damage to cellular components. In contrast, upon reductive stress, insufficient ROS abundance may result in faulty cell signalling. It may be expected that dietary antioxidants, depending on their standard reduction potentials (E°), will affect both scenarios....
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Dia- and paramagnetic contributions to magnetizabilities of relativistic hydrogenlike atoms in some low-lying discrete energy eigenstates
PublicationIn this paper we present tabulated data for relative diamagnetic and paramagentic contributions to the magnetizability ($\chi$) of the relativistic hydrogenlike atoms with a pointlike, motionless and spinless nucleus of charge $Ze$. Utilizing general analytical formulas for the diamagnetic ($\chi_{d}$) and paramagnetic ($\chi_{p}$) components of $\chi$, recently derived by us [P. Stefa{\'n}ska, 2020] with the aid of the Gordon...
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Mechanical and structural investigations of wings of selected insect species
PublicationThis paper presents research and measurements leading to obtaining the Young’s modulus of wing bearing structures of selected insect species. A small testing machine intended for three-point bending and equipped with instruments registering low forces was constructed for the needs of the experiment. The machine was used to perform numerous bending tests of wings of three species of insects (obtained from a breeding farm): Attacus...
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Investigation of the Antifungal Activity and Mode of Action of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimum basilicum, and Eugenia caryophyllus Essential Oils
PublicationThe antimicrobial activity of plant oils and extracts has been recognized for many years. In this study the activity of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimumbasilicum, and Eugenia caryophyllus essential oils (EOs) distributed by Pollena Aroma (Nowy Dwór Mazowiecki, Poland) was investigated against a group of 183 clinical isolates of C. albicans and 76 isolates of C. glabrata. All of...
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A comparative study on the decolorization of Tartrazine, Ponceau 4R, and Coomassie Brilliant Blue using persulfate and hydrogen peroxide based Advanced Oxidation Processes combined with Hydrodynamic Cavitation
PublicationDecolorization of Ponceau 4R, Tartrazine, and Coomassie Brilliant Blue (CBB) was studied using hybrid processes of hydrodynamic cavitation (HC) with potassium persulfate (KPS) and hydrogen peroxide (H2O2). The different properties of these dyes such as hydrophobicity, molecular structures, and molecular weights provided this opportunity to investigate the effects of these factors by comparing the decolorization values of the dyes....
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Research on Tool Temperature Dependence on Lapping Grains Size
PublicationCommonly used as a finishing operation, lapping has been used for achieving ultra-high finishes and close tolerances between mating pieces. Its carried out by applying loose abrasive grains between work and lap surfaces, and causing a relative motion between them resulting in a finish of multi-directional lay. The grains activity (sliding and rolling) in the working gap causes not only the material removal but also the temperature...
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Experimental investigation of the PEM fuel cells performance for automotive and stationary applications
PublicationThe aim of the study was to provide dynamic characteristics of the PEM fuel cell system consisted of Nexa modules, provide steady-state characteristics of the for different values of air excess ratio and steady-state characteristics for different stack temperatures and given load.