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Search results for: wireless sensor networks
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Relability of distributed networks
PublicationNiezawodność sieci jest jednym z parametrów opisujących jakość sieci. Jako parametr niezawodnościowy przyjęto liczbę niezależnych tras pomiędzy każdą parą węzłów. Podano dwie metody projektowania niezawodnych sieci. Jedna z nich wyznacza niezawodną strukturę sieci o minimalnym koszcie, druga wyznacza niezawodną strukturę z minimalną liczbą kanałów.
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Use of Neural Networks in Diagnostics of Rolling-Element Bearing of the Induction Motor
PublicationBearing defect is statistically the most frequent cause of an induction motor fault. The research described in the paper utilized the phenomenon of the current change in the induction motor with bearing defect. Methods based on the analysis of the supplying current are particularly useful when it is impossible to install diagnostic devices directly on the motor. The presented method of rolling-element bearing diagnostics used indirect...
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Directed percolation effects emerging from superadditivity of quantum networks
PublicationEntanglement-induced nonadditivity of classical communication capacity in networks consisting of quantum channels is considered. Communication lattices consisting of butterfly-type entanglement-breaking channels augmented, with some probability, by identity channels are analyzed. The capacity superadditivity in the network is manifested in directed correlated bond percolation which we consider in two flavors: simply directed and...
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Neural Networks, Support Vector Machine and Genetic Algorithms for Autonomous Underwater Robot Support
PublicationIn this paper, artificial neural networks, a classification technique called support vector machine and meta-heuristics genetic algorithm have been considered for development in autonomous underwater robots. Artificial neural networks have been used for seabed modelling as well as support vector machine has been applied for the obstacles classification to avoid some collision problems. Moreover, genetic algorithm has been applied...
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Evaluation of IEEE 802.21 Handover between IEEE 802.11 and UMTS Networks
PublicationThe paper presents IEEE 802.21 - the ongoing standard for network handovers - illustrating its functional features, and considering and simulating a set of scenarios of mobile stations moving between IEEE 802.11 and UMTS networks. In order to evaluate the performance of IEEE 802.21 hanover packet loses and switching delays caused by hanover procedures are investigated. The authors discuss example results of simulation experiments...
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<title>Correction of fiber optic ion sensor readings using a fiber optic temperature sensor</title>
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FIBRE-OPTIC SENSOR FOR SIMULTANEOUS MEASUREMENT OF THICKNESSAND REFRACTIVE INDEX OF LIQUID LAYERS
PublicationIn this paper, we present a fibre-optic sensor for simultaneous measurement of refractive index and thickness of liquid layers. We designed an experimental low-coherence setup with two broadband light sources and an extrinsic fibre-optic Fabry–Pérot interferometer acting as the sensing head. We examined how the refractive index of a liquid film and its thickness affect spectrum at the output of a fibre-optic interferometer. We...
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Electrochemical performance of indium-tin-oxide-coated lossy-mode resonance optical fiber sensor
PublicationAnalysis of liquids performed in multiple domain, e.g., optical and electrochemical (EC), has recently focus significant attention. Our previous works have shown that a simple device based on indium-tin-oxide (ITO) coated optical fiber core may be used for optical monitoring of EC processes. At satisfying optical properties and thickness of ITO a lossy-mode resonance (LMR) effect can be obtained and used for monitoring of optical...
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Investigation of sour substances by five-channel potentiometric taste sensor containing all-solid-state-electrodes ( ASSEs)
PublicationAn elaboration of taste sensor for discrimination of different food products is of great importance for food industry. Potentiometric taste sensor containing ion selective electrodes with lipid/polymer membranes has already been applied commercially in food industry. However, time-consuming and demanding preconditioning method of ions selective electrodes as well as maintenance of electrodes’ bodies are disadvantages of this taste...
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INVESTIGATION OF SOUR SUBSTANCES BY FIVE-CHANNEL POTENTIOMETRIC TASTE SENSOR CONTAINING ALL-SOLID-STATE- ELECTRODES (ASSEs)
PublicationAn elaboration of taste sensor for discrimination of different food products is of great importance for food industry. Potentiometric taste sensor containing ion selective electrodes with lipid/polymer membranes has already been applied commercially in food industry. However, time-consuming and demanding preconditioning method of ions selective electrodes as well as maintenance of electrodes’ bodies are disadvantages of this taste...
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The Analysis and Solutions to the Problems of IPv6 Configuration Migration of Small Networks
PublicationThe paper analyzes the problems of IPv4 to IPv6 migration processes and indicates the areas in which migration can be done without expensive replacement of hardware, software and organizational changes. This paper presents the migration tools developed for the SOHO network administrators. The tools provide theoretical knowledge and practical advices on migrating to IPv6 and enable automation of the migration process. The article...
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Determination of chemical oxygen demand (cod) at boron-doped diamond (bdd) sensor by means of amperometric technique
PublicationA boron-doped diamond (BDD) sensor was proposed for effective detection of chemical oxygen demand (COD) by means of amperometric technique. Thin boron doped diamond active sensor layer was deposited on Si wafer and glassy carbon substrate by Microwave Plasma Enhanced Chemical Vapor Deposition (MW PE CVD). The structure of BDD was confirmed by Raman spectra analysis. Broad Raman bands centered at 482 cm-1 and 1219 cm-1 are typical...
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Measurements and Visualization of Sound Intensity Around the Human Head in Free Field Using Acoustic Vector Sensor
PublicationThis paper presents measurements and visualization of sound intensity around the human head simulator in a free field. A Cartesian robot, applied for precise positioning of the acoustic vector sensor, was used to measure sound intensity. Measurements were performed in a free field using a head and torso simulator and the setup consisting of four different loudspeaker configurations. The acoustic vector sensor was positioned around...
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Determination of Chemical Oxygen Demand (COD) at Boron-doped Diamond (BDD) Sensor by Means of Amperometric Technique
PublicationA boron-doped diamond (BDD) sensor was proposed for effective detection of chemical oxygen demand (COD) by means of amperometric technique. Thin boron doped diamond active sensor layer was deposited on Si wafer and glassy carbon substrate by Microwave Plasma Enhanced Chemical Vapor Deposition (MW PE CVD). The structure of BDD was confirmed by Raman spectra analysis. Broad Raman bands centered at 482 cm-1 and 1219 cm-1 are typical...
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A measurement method for lossy capacitive relative humidity sensors based on a direct sensor-to-microcontroller interface circuit
PublicationA new time-domain measurement method for determining the capacitance and resistance values of lossy relative humidity capacitive sensors is presented. The method is based on a direct sensor-to-microcontroller interface for microcontrollers with internal analog comparators and timers. The interface circuit consists only of four reference resistors (two reference resistors if a microcontroller includes a voltage reference source),...
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Optimum Choice of Randomly Oriented Carbon Nanotube Networks for UV-Assisted Gas Sensing Applications
PublicationWe investigated the noise and photoresponse characteristics of various optical transparencies of nanotube networks to identify an optimal randomly oriented network of carbon nanotube (CNT)-based devices for UV-assisted gas sensing applications. Our investigation reveals that all of the studied devices demonstrate negative photoconductivity upon exposure to UV light. Our studies confirm the effect of UV irradiation on the electrical...
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Process control of air stream deodorization from vapors of VOCs using a gas sensor matrix conducted in the biotrickling filter (BTF)
PublicationThis article presents the validity, advisability and purposefulness of using a gas sensor matrix to monitor air deodorization processes carried out in a peat-perlite-polyurethane foam-packed biotrickling filter. The aim of the conducted research was to control the effectiveness of air stream purification from vapors of hydrophobic compounds, i.e., n-hexane and cyclohexane. The effectiveness of hydrophobic n-hexane and cyclohexane...
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Discriminatory expressions, the young and social networks: The effect of gender
PublicationIn the framework of the «Project I: CUD» (Internet: Creatively Unveiling Discrimination), carried out in the United Kingdom, Italy, Belgium, Romania and Spain, we conducted a study into the expressions of discrimination used by young people on social network sites. To do so we designed a methodological strategy for detecting discriminatory content in 493 Facebook profiles and used this strategy to collect 363 examples for further...
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Electrocatalytic gas sensor response analysis
PublicationW pracy przedstawiono i porównano metody analizy odpowiedzi elektrokatalitycznych czujników gazów toksycznych. Opisane metody pozwalają na ekstrakcje z odpowiediz czujników informacji o rodzaju gazu oraz o jego stężeniu.
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Nanocrystalline undoped ceria oxygen sensor.
PublicationW pracy przedstawiono wyniki badań struktury i elektrycznych właściwości nanokrystalicznego czujnika na bazie niedomieszkowanego tlenku ceru. Zbadano wpływ ciśnienia parcjalnego tlenu na rezystancję cienkowarstwowego tlenku ceru. Konduktancja tlenku ceru w zakresie stężeń tlenu od 10ppm do 100% ma charakter eksponecjalny z parametrem -0.25. Zbadano szybkość odpowiedzi oraz wpływ dwutlenku azotu oraz dwutlenku siarki na odpowiedź...
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Selectivity of amperometric sulfur dioxide sensor.
PublicationW pracy przedstawiono wartości współczynników selektywności amperometrycznego czujnika ditlenku siarki względem siarkowodoru. Obliczenia wykonane zostały w oparciu o krzywe kalibracyjne wyznaczone dla zaprezentowanego wcześniej przez nas amperometrycznego czujnika ditlenku siarki. Analiza krzywych kalibracyjnych pod względem czułości oznaczenia oraz analiza wartości amperometrycznych współczynników selektywności odgrywa dużą pomocniczą...
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Sztuczny sensor smaku a zmysł smaku
PublicationOmówiono klasy smaku i działanie zmysłu smaku, który odgrywa ogromną rolę w ocenie jakości żywności metodami organoleptycznymi. Metody te nie są w pełni obiektywne, stąd poszukiwanie sztucznego sensora smaku. Przedstawiono szereg rozwiązań prowadzących do opracowania sensora smaku na większą skalę. Omówiono wybrane potencjometryczne i woltamperometryczne sensory smaku, a także ich handlowe modele.
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Optimal Sensor Placement for Damage Detection
PublicationW pracy przedstawiono dwie konfiguracje czujników PZT do detekcji uszkodzeń w płytach. Omówion zalety i wady obu konfiguracji.
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Optimization of a Fabry-Perot Sensing Interferometer design for an optical fiber sensor of hematocrit level
PublicationContinuous measurement of the hemato crit level in blo o d can p otentially b e p erformed using optical bre sensors. The FabryPerot interferometric sensors are a promising candidate in this application. The most imp ortant step in the design of the sensor is design of the sensing interferometer. Adequate cavity length and high interference contrast are two most imp ortant requirements in this application. The design metho d of...
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Physics-guided neural networks (PGNNs) to solve differential equations for spatial analysis
PublicationNumerous examples of physically unjustified neural networks, despite satisfactory performance, generate contradictions with logic and lead to many inaccuracies in the final applications. One of the methods to justify the typical black-box model already at the training stage and lead to many inaccuracies in the final applications. One of the methods to justify the typical black-box model already at the training stage involves extending...
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System Loss Model for Body Area Networks in Room Scenarios
PublicationThis paper presents an analysis of system loss in Body Area Networks for room scenarios, based on a wideband measurement campaign at 5.8 GHz. The measurements were performed with a fixed antenna transmitting vertically and horizontally polarised signals, while the user wears dualpolarised antennas. The average system losses in co- and crosspolarised channels are 41.4 and 42.6 dB for vertically polarised transmitted signals and...
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TDOA versus ATDOA for wide area multilateration system
PublicationThis paper outlines a new method of a location service (LCS) in the asynchronous wireless networks (AWNs) where the nodes (base stations) operate asynchronously in relation to one another. This method, called asynchronous time difference of arrival (ATDOA), enables the calculation of the position of the mobile object (MO) through the measurements taken by a set of non-synchronized fixed nodes and is based on the measurement of...
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New Alternative Passive Networks to Improve the Range Output Voltage Regulation of the PWM Inverters
PublicationThis paper presents different topologies of buck-boost converters with passive input networks that have alternative topologies; this is known in the literature as a Z-source inverter. Alternative passive networks were named by the authors as T-inverters; these improve output voltage regulation of the PWM inverters. T-inverter has fewer reactive components in comparison to conventional Z-source inverter. The most significant advantage...
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A novel luminescent chemical sensor for the determination of Pb 2+ and Cu 2+ ions
PublicationSilica xerogel surface grafted with aminopropyl (PrNH2) groups was additionally treated by cetyltrimethylammonium bromide (CTAB) surfactant and ascorbic acid (asc) in alkaline solution. This material symbolized as SiO2-PrNH2-CTAB/asc, proved to be a stable luminescent material, exhibited an emission band peaked at 393 nm under excitation wavelength 335 nm. Time evolution of the band intensity suggests changes of defect concentration...
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Service-based Resilience via Shared Protection in Mission-critical Embedded Networks
PublicationMission-critical networks, which for example can be found in autonomous cars and avionics, are complex systems with a multitude of interconnected embedded nodes and various service demands. Their resilience against failures and attacks is a crucial property and has to be already considered in their design phase. In this paper, we introduce a novel approach for optimal joint service allocation and routing, leveraging virtualized...
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The Analysis of Cross-Polarisation Discrimination for Body Area Networks in Cylindrical Metallic Environment
PublicationThe analysis of cross-polarisation discrimination for Body Area Networks in an untypical environment of cylindrical metallic room has been performed in the paper. This analysis was done based on the measurements carried out for dynamic narrowband off-body channels operating at the frequency of 2.45 GHz. The results have shown that there is a strong dependence of the depolarisation effect on the existence of direct component in...
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A novel approach exploiting properties of convolutional neural networks for vessel movement anomaly detection and classification
PublicationThe article concerns the automation of vessel movement anomaly detection for maritime and coastal traffic safety services. Deep Learning techniques, specifically Convolutional Neural Networks (CNNs), were used to solve this problem. Three variants of the datasets, containing samples of vessel traffic routes in relation to the prohibited area in the form of a grayscale image, were generated. 1458 convolutional neural networks with...
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Simultaneous optical and electrochemical label-free biosensing with ITO-coated lossy-mode resonance sensor
PublicationIn this work we discuss a new label-free biosensing device based on indium tin oxide (ITO) overlaid section of a multimode optical fiber fused silica core. The sensor has been used to optical measurements also simultaneously interrogated electrochemically (EC). Due to optimized thickness and optical properties of ITO film, a lossy-mode resonance (LMR) could be observed in the optical domain, where electrical properties of the film...
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Enhanced voice user interface employing spatial filtration of signals from acoustic vector sensor
PublicationSpatial filtration of sound is introduced to enhance speech recognition accuracy in noisy conditions. An acoustic vector sensor (AVS) is employed. The signals from the AVS probe are processed in order to attenuate the surrounding noise. As a result the signal to noise ratio is increased. An experiment is featured in which speech signals are disturbed by babble noise. The signals before and after spatial filtration are processed...
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Improving voltage levels in low-voltage networks with distributed generation – case study
PublicationThe use of distributed generation in low-voltage networks may cause the voltage variation in them, within the wide range. In unfavourable circumstances, the voltage may reach unacceptable values. The paper presents the effect of distributed generation on voltage levels in a selected low-voltage rural distribution network in Poland. An analysis of possible methods for improving voltage levels in this network is conducted. The most...
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System Loss Model for Body-to-Body Networks in Indoor and Outdoor Environments
PublicationA system loss model for body-to-body networks in indoor and outdoor environments is proposed in this paper, based on measurements taken at 2.45 GHz. The influence of the type of environment, antenna visibility and user mobility on model parameters has been investigated. A significant impact of mutual antennas’ placement and their visibility is shown. The proposed model fits well to empirical data, with the average root mean square...
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Experimental Comparison of Designed Inductance Coils for Wireless Power Transfer
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Research and Development of Inductive-Resonant Wireless Power Transfer System
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Coil Design for Wireless Power Transfer with Series-Parallel Compensation
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Hybrid Excited Synchronous Machine with Wireless Supply Control System
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Enforsing cooperative behaviour in multi wireless ad-hoc network.
PublicationMechanizmy kontroli przekazywania pakietów tranzytowych w rozległych sieciach had-hoc wykorzystują nasłuchiwanie pakietów transmitowanych przez stacje sąsiednie i ich porównywanie z zachowanymi kopiami. W pracy pokazuje się możliwość egoistycznych zachowań stacji podlegających na niekontrolowanej admisji pakietów źródłowych, a następnie odmowie przyjmowania pakietów tranzytowych z powodu przepełnienia lokalnej pamięci buforowej.
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Handwritten signature verification system employing wireless biometric pen
PublicationThe handwritten signature verification system being a part of the developed multimodal biometric banking stand is presented. The hardware component of the solution is described with a focus on the signature acquisition and on verification procedures. The signature is acquired employing an accelerometer and a gyroscope built-in the biometric pen plus pressure sensors for the assessment of the proper pen grip and then the signature...
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Multihomed Wireless Terminals: MAC Configuration and Network Selection Games
PublicationW artykule rozpatruje się rozdział pasma pomiędzy zbiór racjonalnych terminali bezprzewodowych dołączonych do wielu sieci lokalnych. Przy pomocy narzędzi analitycznych teorii gier pokazuje się, w jaki sposób można zniechęcać terminale do agresywnej konfiguracji protokołu MAC. Analizowana jest ilościowo rola prędkości generacji informacji zwrotnej z sieci w stosunku do częstości generacji żądań dostępu terminala do sieci. Wykazano,...
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Optical properties of thin TiO2 film deposited on the fiber optic sensor head
PublicationThe presented study was focused on investigation of the titanium dioxide (TiO2) thin film deposited on the fiber tip. The intention of this investigation was using TiO2 film in the construction of the optical fiber sensor head. In the demonstrated construction TiO2 thin layer was deposited on the tip of a commonly used telecommunication single mode optical fiber (SMF-28) by means of the Atomic Layer Deposition (ALD). Thickness...
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Low-strain sensor based on the flexible boron-doped diamond-polymer structures
PublicationA free-standing high boron-doped diamond nanosheet (BDDNS) has been fabricated for the development of a flexible BDDNS strain senor. High boron-doped diamond was initially grown on a tantalum substrate in a microwave plasma-assisted chemical vapor deposition method, and was then transferred to a Kapton polymer substrate to fabricate the flexible BDDNS/Kapton device. Before performing the transfer process, the thin BDDNS’s morphology...
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Characteristics of an image sensor with early-vision processing fabricated in standard 0.35 µm CMOS technology
PublicationThe article presents measurement results of prototype integrated circuits for acquisition and processing of images in real time. In order to verify a new concept of circuit solutions of analogue image processors, experimental integrated circuits were fabricated. The integrated circuits, designed in a standard 0.35 µm CMOS technology, contain the image sensor and analogue processors that perform low-level convolution-based image...
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Supply current signal and artificial neural networks in the induction motor bearings diagnostics
PublicationThis paper contains research results of the diagnostics of induction motor bearings based on measurement of the supply current with usage of artificial neural networks. Bearing failure amount is greater than 40% of all engine failures, which makes their damage-free operation crucial. Tests were performed on motors with intentionally made bearings defects. Chapter 2 introduces the concept of artificial neural networks. It presents...
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Settlement Networks in Polish Spatial Development Regional Plans
PublicationIn 1999, ten years after the great political changes in Poland, 16 self-governed regions (in Polish: voivodeship) were created. According to Polish law, voivodeship spatial development plans, or regional plans in short, determine basic elements of the settlement network. No detailed regulations indicate the specific elements of the settlement network or what features of these elements should be determined. For this reason, centres...
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Generation-recombination and 1/f noise in carbon nanotube networks
PublicationThe low-frequency noise is of special interest for carbon nanotubes devices, which are building blocks for a variety of sensors, including radio frequency and terahertz detectors. We studied noise in as-fabricated and aged carbon nanotube networks (CNNs) field-effect transistors. Contrary to the majority of previous publications, as-fabricated devices demonstrated the superposition of generation-recombination (GR) and 1/f noise...
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Potentiometric sensor containing set of ion selective electrodes with lipid modified membranes for quality assessment of tested non-alcoholic beverages
PublicationPotentiometric sensors may be a good tool for fast quality control of commercial drinks. In this work, such a sensor, containing a set of ion-selective electrodes with lipid-modified membranes (benzylhexadecyldimethylammonium chloride monohydrate, hexadecylamine, 1-dodecanol, elaidic acid, cholesterol) was used for discrimination and quality control of non-alcoholic beverages, mainly composed of sugar and citric acid. It was found...