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Does the Use of Cell Phones and Headphones at the Signalised Pedestrian Crossings Increase the Risk of Accident?
PublicationReduction of the number of fatalities among pedestrians remains a topical issue in Poland. For many years, this percentage has remained at around 30% of all those who were killed on the road. At the same time, there is an increase in the use of electronic devices by pedestrians and cyclists that may affect their perception when crossing the road. This can lead to traffic accidents. In order to investigate the problem, field studies...
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Equivalent standard manoeuvres for pod-driven ships
PublicationProcedures for carrying out the manoeuvring tests presented in International Maritime Organisation (IMO) resolution MSC.137(76) are based on the capabilities of ships with conventional steering-propulsion systems. Therefore they do not correspond to ships with other steering-propulsion devices, like pod drives. IMO is aware of this shortcoming and for ships with non-conventional steering and propulsion system may permit the use...
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Innovative Research Into Road Restraint Systems
PublicationKey to understanding the needs and building road infrastructure management tools to prevent and mitigate run-off-road accidents is to identify hazards and their sources which are a result of wrong design, construction, installation and maintenance of road restraint systems [1]. Building such tools requires advanced studies with field tests, simulations and models to demonstrate the effects of selected parameters on road user safety...
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Using On-line Measurement by Electronic Nose and Computer Simulations for Real-time Control at WWTP
PublicationContinuous investigation of wastewater quality can be carried out by a device called an e-nose. One important feature of the proposed real-time control system for WWTP is that using on-line measurements by e-nose together (Figure 1) with technological sets picked on this basis by means of computer models, it is possible to change treatment process parameters, depending on the current quality of wastewater. It can be used for the...
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An Experimental Investigation of Pressure Wave Celerity During the Transient Slurry Flow
PublicationTransportation of slurries in pressure pipelines is an example of a complex flow due to specific parameters of transported medium. For practitioners, the economy of designing and maintenance is usually the most important factor. For this reason, most of hydrotransport installations are fairly simple; however, they become more vulnerable to negative effects of the transient flow which can occur in pressure pipelines. As the consequence,...
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Microstructure and corrosion behaviour of carbon steel and ferritic and austenitic stainless steels in NaCl solutions and the effect of p-nitrophenyl phosphate disodium salt
PublicationThe microstructure and corrosion behavior of carbon steel (CSA516) and ferritic (SS410) and austenitic (SS304L) stainless steels were studied and compared. Corrosion tests were carried out in 0.5 M NaCl solutions. Rates of corrosion were monitored based on weight loss, Tafel extrapolation and linear polarization resistance (LPR) methods. Rates of corrosion were ranked following the order: CSA516 >> SS410 > SS304L. The impact of...
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Influence of temperature on the activity of anammox granular biomass.
PublicationThe aim of this study was to determine a short-term and long-term effect of temperature on the anammox rate and determination of temperature coefficients in the Arrhenius and Ratkowsky equations. The short-term effects of temperature on the anammox granular biomass were investigated in batch tests at ten different temperatures in the range of 10–55 °C. The maximum overall nitrogen removal rate of 1.3 gN gVSS−1·d−1 was observed...
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Study of the formation of calcareous deposits on cathodically protected steel in Baltic sea water
PublicationPurpose – The purpose of this paper is to investigate whether the sedimentation of calcareous deposits occurs on cathodically protected steel in Baltic sea water. Design/methodology/approach – Steel electrodes were cathodically polarized in natural Baltic sea water at potential þ0.150 V vs Zn electrode in potentiostatic mode. During exposure chronoamperometric measurements were carried out. After the exposure, the electrode’s surface...
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Monte Carlo simulations of the fracture resistance degradation of asphalt concrete subjected to environmental factors
PublicationThe paper presents the results of laboratory tests of SCB (semi-circular beam) samples of asphalt concrete, subjected to the destructive effect of water and frost as well as the aging processes. The determined values of material parameters show significant dispersions, which makes the design of mixtures difficult. Statistical analysis of the test results supplemented by computer simulations made with the use of the proprietary...
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Kinetics of hexane and cyclohexane biodegradation using Candida subhashii in mineral salt medium in the presence of DES solution
Open Research DataDataset presents results of investigations on kinetics of biodegradation of hexane and cyclohexane in Candida subhashii.
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Tropospheric parameters derived from the selected IGS stations in the global tropics for the years 2001-2018
Open Research DataThis dataset contains daily GNSS-derived zenith tropospheric delay (ZTD), a posteriori corrected zenith wet delay (ZWD), and precipitable water vapour (PWV) time series. These troposphere-related data were estimated for the period between January 2001 and December 2018, for the 43 International GNSS Service (IGS) stations, located in the global tropics....
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Employees’ self-expansion, work conditions, work engagement and productive behaviours: study 1&2
Open Research DataIn the following studies conducted in Poland, we examined the importance of workplace self-expansion and found that it is a significant mediator between job resources (e.g. compensation and benefits, job tasks) and work engagement (Study 1) as well as task-oriented engagement (Study 2). At the same time, our findings prove that job demands (e.g. role...
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Revenues to the state budget from the sale of shares in state-owned banks in 1994-2000
Open Research DataOn June 14, 1996, a special law was passed on the merger and grouping of certain banks in the form of joint-stock companies. Pursuant to these regulations, the PeKaO S.A. banking group was established, which was the only entity of this type established in this way. Additionally, by the end of 1996, four out of nine regional banks were sold, i.e. Wielkopolski...
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Electrochemical impedance spectroscopy measurements - conductivity vs. temperature and conductivity vs. oxygen partial pressure - BaCe0.6Zr0.2Y0.1Tb0.1O3-δ
Open Research DataThe dataset consists of two main catalogs consisting of measurement data: of the electrical conductivity of the BaCe0.6Zr0.2Y0.1Tb0.1O3-δ (BCZYTb) sample as a function of temperature and of the electrical conductivity as a function of oxygen partial pressure (pO2). Measurements as a function of temperature were carried out in dry and wet air (pH2O ~...
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The Mott-Schottky characteristics of microwave pulsed-plasma polymerized allylamine by DEIS analysis
Open Research DataThe dataset contains the results obtained for the Mott-Schottky analysis of the microwave pulsed-plasma polymerized allylamine using the multifrequency perturbation signal with Dynamic Electrochemical Impedance Spectroscopy (DEIS) technique. The results were obtained using the perturbation composed of the elementary signals with a frequency range between...
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Collective angst and collective action for progressive city policies: study1
Open Research DataPaweł Adamowicz, the liberal mayor of Gdańsk, died on January 14, 2019, after being stabbed by a man who rushed onstage during a charity event. Three studies were carried out to analyze the predictors of willingness to engage in collective action for the support of the progressive city policies he initiated. In this study 1 (N = 214), the questionnaire,...
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Linear impedance of vanadate glasses containing BaTiO3
Open Research DataThe linear impedance of vanadate glasses doped with BaTiO3 was measured. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on a preheated (573...
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Linear impedance of 2Si3N4–98(40Na2O-20CaO-40P2O5) glass measured with impedance spectroscopy method at low temperature region
Open Research DataThe linear electrical properties of 2Si3N4–98(40Na2O-20CaO-40P2O5) glass was measured by impedance spectroscopy method.
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Linear impedance of V2O5 nanorods obtained at 923K
Open Research DataThe DataSet contains the linear electrical properties of V2O5 nanorods which were measured by the impedance spectroscopy method. V2O5 nanorods were obtained by the sol-gel method. The information about xerogel powder synthesis is described in the Journal of Nanomaterials. The precursor powder was pressed into the disk-shaped pellets (12mm in diameter...
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Crack Resistance of Asphalt Concrete Subjected to Environmental Factors
PublicationThe paper presents an analysis of the influence of environmental factors on the cracking susceptibility of asphalt concrete resulting in a change in the durability of asphalt pavement. In order to assess the phenomenon, laboratory tests were carried out taking into account the destructive effects of moisture, freeze-thaw cycle and long-term ageing. The influence of both factors occurring simultaneously was also verified. Due to...
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Przyczyny uszkodzeń i sposób naprawy posadzki ze styrobetonu
PublicationW artykule opisano uszkodzenia, badania i sposób naprawy posadzki wykonanej na istniejącym stropie żelbetowym o powierzchni ok. 1050 m2 i podłożu ze styrobetonu. W posadzce stwierdzono znaczne uszkodzenia w postaci zarysowań, odspojeń i nierówności. W celu określenia ich przyczyn wykonano badania in situ oraz badania laboratoryjne. Stwierdzono, że przyczyną powstania uszkodzeń są błędy wykonawcze. Wykonano próbną naprawę uszkodzeń...
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An insight into craft activities in rural areas of Dalmatia province - first data on iron working at the Roman settlement in Lopar (Island of Rab)
PublicationWithin multidisciplinary research carried out at Podšilo bay in Lopar on the island of Rab (north-eastern Adriatic), on the bases of movable finds and, possibly, geophysical measurements, evidence of ironworking has been detected within a Roman rural site where ceramic building materials production was ascertained before. Preliminary analyses of several samples of slug, iron objects and nearby collected minerals support the...
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Hydrodynamic Pressure Field of a Ship on Shallow Water
PublicationResults of calculations of the hydrodynamic pressure field around the ship were obtained by application of the boundary element method. Hydrodynamic field was calculated for a Polish Navy’s tugboat and transport ship using a program called SHiPP and compared with measurements of the field taken on river near Swinoujscie for two identical tugs H-4 and H-10. Next, a series of HPF calculations was carried out on planes situated at...
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Numerical estimation of the pile toe and shaft unit resistances during the installation process in sands
PublicationNumerical simulations of a pile jacking were carried out. A Coupled Eulerian–Lagrangian (CEL) formulation was used to treat with large deformation problems. An Abaqus, a commercial Finite Element Method software suit, was used as a computing environment. The Mohr–Coulomb constitutive model was applied and the Coulomb model of friction was used to describe pile-soil interaction. Calculations were made for three different pile diameters....
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Evaluation of Sound Enhancement in Mobile Device Using Virtual Bass Synthesiss Algorithm
PublicationAn experiment conducted to validate possibility of use virtual bass synthesis (VBS) algorithm in a portable computer is presented. The subjective listening tests based on the procedure of pairwise comparison between VBS, based on the so-called missing fundamental phenomenon, and standard bass boost technique are employed. The evaluation was carried out in two types of conditions: in a professional listening room and employing an...
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Theoretical analysis of the cable-stayed bridge over brda river in Bydgoszcz
PublicationThe topic of this article is the numerical analysis carried out for the cable-stayed tram (road) bridge over Brda river in Bydgoszcz. The goal of numerical studies was the verification of project assumptions and construction solutions elaborated by the autonomous team. The bridge calculations were conducted on three independent FEM models The internal forces and the elements effort under different loading schemes were examined....
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Niekorzystny wpływ przekształtnikowego zasilania PWM na silniki asynchroniczne trakcyjne
PublicationThe electric traction drives with an AC motor fed by a frequency converter are used more and more often nowadays. The most significant side effects, of a converter's output voltage forming PWM method for AC motor windings, are steep voltage changes, which can initiate several destructive phenomena. The paper presents the adverse influence of a converter common mode voltage on the motor windings' increased voltage exposure and the...
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Destructive impact of PWM inverters on traction AC motors
PublicationThe electric traction drives with an AC motor fed by a frequency converter are used more and more often nowadays. The most significant side effects, of a converter's output voltage forming PWM method for AC motor windings, are steep voltage changes, which can initiate several destructive phenomena. The paper presents the adverse influence of a converter common mode voltage on the motor windings's increased voltage exposure and...
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Destructive Consequences of PWM Inverter Feeding for Traction AC Motors
PublicationThe electric traction drives with an AC motor fed by a frequency converter are used more and more often nowadays. The most significant side effects, of a converter's output voltage forming PWM method for AC motor windings, are steep voltage changes, which can initiate several destructive phenomena. The paper presents the adverse influence of a converter common mode voltage on the motor windings' increased voltage exposure and the...
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Revalorisation of the Szewalski’s concept of the law of varying the last-stage blade retraction in a gas-steam turbine
PublicationThe article presents the implementations of the free vortex law to the blade of the last stage of a gas-steam turbine. First, a thermodynamic analysis was carried out, determining the parameters at the inlet, then the number of stages of the high and low-pressure part of the turbine was constructed, together with the kinematics and velocity vectors for subsequent stages of the axial turbine. The last step of article was to take...
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Measurement of expenditure efficiency of Polish cities with county rights in the context of quality of life
PublicationThe article is devoted to the measurement of efficiency of overall expenditures. The purpose of the study is to evaluate the efficiency of use of budget resources by local government units in the context of fostering quality of life. The subject of the study is 65 Polish cities with county rights (county status). Calculations were carried out using Data Envelopment Analysis (DEA). The results of analysis confirm the two research...
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The Finite Elements Method application to assesment the impact of turbulence generated by wind turbines on their lacation inclose proximity of overhead high voltage power transmissionlines
PublicationThe paper presents selected aspects of construction of wind turbines location concerning aerodynamic impact on power lines. Reaserch is based on the source data concerning the aerodynamic impact of a wind farm consisting of 8 turbines and 400 kV power line, an analysis of the possibility of wind farm locating in the immediate vicinity of the line was carried out. There are serious problems with locating higher capacity wind farms...
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The use of machine learning for face regions detection in thermograms
PublicationThe aim of this study is to analyse the methods of detecting characteristic points of the face in thermographic images. As part of the implementation an extensive analysis of scientific publications covering similar issues both for the analysis of images made in visible light and thermographic images was carried out. On the basis of this analysis, 3 models were selected and then they were implemented and tested on the basis of...
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Comparison of Mathematical Models of Torque Transmitted by Multi-disc Wet Clutch with Experimental Results
PublicationIn this article was described the methodology for the experimental study of flows in the prototype of a satellite hydraulic motor with a rotating body. The experimental tests of the motor were carried out at a low constant rotational speed in a wide range of pressure drop in this motor. The constant rotational speed of the motor was kept by a worm gear. Based on the test results, the leakage characteristics in the flat gaps of...
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Experimental Study of Flow Rate in Hydraulic Satellite Motor with the Rotating Case at a Low Constant Rotational Speed
PublicationIn this article was described the methodology for the experimental study of flows in the prototype of a satellite hydraulic motor with a rotating body. The experimental tests of the motor were carried out at a low constant rotational speed in a wide range of pressure drop in this motor. The constant rotational speed of the motor was kept by a worm gear. Based on the test results, the leakage characteristics in the flat gaps of...
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Innovative rehabilitation lifts – mechanics in medical devices
PublicationMechanical devices are now widely used in physiotherapy and other rehabilitation processes. Particular importance is attached to devices enabling easy and effective transport of disabled people. The article presents innovative designs of rehabilitation lifts offered by the Polish manufacturer of lifts and medical accessories, LeviCare company. Moreover, the main assumptions of the research and development project implemented by...
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Ernst Cassirer’s Idea of the Critique of Knowledge
PublicationThe article analyses systematically and historically the specific idea of transcenden-talism developed in the Marburg School of Neo-Kantianism. The unique line of the Marburg’s School interpretation of Kant’s critical philosophy consists in contrasting critical (relational) and dogmatic (substantial) understandings of basic philosophical concepts. This line is characteristic of the Marburg School...
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Design and implementation of the driver system for Hamamatsu C12880MA microspectrometer
PublicationRecent miniaturization developments in devices for spectroscopy have reduced greatly their costs and increased their availability for a wide range of users and applications. This paper presents the design and implementation of a driver system for a Hamamatsu C12880MA microspectrometer. The system implementation was carried out and compared using two independent microcontroller modules: Arduino Uno and STM32F411RE Nucleo. We assessed...
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Surface quality control of a thin SiN layer by optical measurements
PublicationFiber optic interferometers have a wide range of applications, including biological and chemical measurements. Nevertheless, in the case of a reflective interferometer setup, standard silver mirrors cannot be used in every measurement, due to their chemical activity. This work investigates the surface quality of a thin optical layer of silicon nitride (SiN), which can serve as an alternative material for silver mirrors. We present...
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Local basis function estimators for identification of nonstationary systems
PublicationThe problem of identification of a nonstationary stochastic system is considered and solved using local basis function approximation of system parameter trajectories. Unlike the classical basis function approach, which yields parameter estimates in the entire analysis interval, the proposed new identification procedure is operated in a sliding window mode and provides a sequence of point (rather than interval) estimates. It is...
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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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Signal Processing in the Investigation of Two-phase Liquid-gas Flow by Gamma-ray Absorption
Publicationn this paper, the use of the gamma-absorption method applied in the investigation of the two-phase liquid-gas flow in the pipeline is described. An example of its application to the air transported by water in a horizontal pipeline is evaluated. In the measurements, Am-241 radioactive sources and probes with Nal (Tl) scintillation crystals have been used. The signals from the radiometric set were used to determine the velocity...
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Suitability of LoRaWAN Technology for the Development of Maritime Applications
PublicationThe LoRaWAN Technology opens new possibilities for gathering and analysis of distributed data. In the paper we concentrate on its maritime usability which was tested by us in the period from June to August 2018. Measurements of the LoRaWAN network coverage in the Bay of Gdansk area were carried out. Various conditions and places were tested. The research was planned in such a way as to gradually increase the range and control the...
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Extending transition curve in analytical design method
PublicationThe paper presents the problem of extending the transitional curves, using for this purpose an analytical design method. The basis for the analysis of numerical calculations were carried out for a wide set of parameters characterizing the standard geometric system. We considered an importance of the size of radius of the circular arc and return angle of route on the obtained results after the formulation of appropriate theoretical...
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New concept and analysis of the multicell piezoelectric motor
PublicationThis work presents the design, modeling and tests of the prototype multicell piezoelectric motor (MPM). A new concept of the electromechanical structure of the considered prototype is based on three rotating-mode actuators. The electromechanical structure of each actuator has been considered as an independent one - referred to as a ”single cell” (single actuator). Combined three resonant actuators generate three traveling waves...
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Search for the most useful geometry of an acoustic journal bearing
PublicationComputer simulations of a number of journal bearing’s geometries utilising acoustic levitation were carried out. The choice of the best geometry depended on the ability of a deformed shape, created by piezo-electric elements, to facilitate squeeze film ultrasonic levitation, and also to create three evenly distributed diverging aerodynamic gaps. Deformations of analysed variants of the bearing’s shape were generated by numerical...
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Chosen Analysis Results Of The Prototype Multicell Piezoelectric Motor
PublicationThis paper presents the design, modeling and tests of the prototype multicell piezoelectric motor (MPM). A new concept of the electromechanical structure of the considered prototype is based on three rotating-mode actuators. The electromechanical structure of each actuator has been considered as an independent one - referred to as a “single cell” (single actuator). Combined three resonant actuators generate three traveling waves...
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Lattice filter based autoregressive spectrum estimation with joint model order and estimation bandwidth adaptation
PublicationThe problem of parametric, autoregressive model based estimation of a time-varying spectral density function of a nonstationary process is considered. It is shown that estimation results can be considerably improved if identification of the autoregressive model is carried out using the two-sided doubly exponentially weighted lattice algorithm which combines results yielded by two one-sided lattice algorithms running forward in...
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DEEP CONVOLUTIONAL NEURAL NETWORKS AS A DECISION SUPPORT TOOL IN MEDICAL PROBLEMS – MALIGNANT MELANOMA CASE STUDY
PublicationThe paper presents utilization of one of the latest tool from the group of Machine learning techniques, namely Deep Convolutional Neural Networks (CNN), in process of decision making in selected medical problems. After the survey of the most successful applications of CNN in solving medical problems, the paper focuses on the very difficult problem of automatic analyses of the skin lesions. The authors propose the CNN structure...
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The electrochemical response to glassy carbon electrode modification steps towards viral electrochemical immunosensor preparation
Open Research DataThe dataset contains the electrochemical measurements (CV/EIS) carried out for the consecutive steps of the glassy carbon GC electrode functionalization, in separate subfolders, as described. The cyclic voltammetry (CV) was conducted using a Palmsens 4 potentiostat/galvanostat system (Methrom, Autolab, Netherlands) in the standard three-electrode configuration,...