Filtry
wszystkich: 1381
wybranych: 1053
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: VOLTAIRE
-
Zastosowanie specjalnego uziemienia żył powrotnych w liniach kablowych SN
PublikacjaW artykule porównano metody uziemiania żył powrotnych kabli średniego napięcia. Głównym kryterium oceny poszczególnych rozwiązań było ograniczenie strat w przesyle energii elektrycznej oraz zapewnienie ochrony przeciwprzepięciowej osłon kabli. Na podstawie symulacji kabli zamodelowanych w programie CYMCAP i otrzymanych wyników obciążalności prądowej i strat w linii zaprezentowano metodę krzyżowania żył powrotnych (CB – cross-bonding...
-
Metody doboru miejsc zainstalowania zasobników energii w sieciach elektroenergetycznych niskiego napięcia
PublikacjaW związku z rosnącą liczbą źródeł odnawialnych przyłączanych do sieci niskiego napięcia (nn) jakość energii elektrycznej w tej sieci ulega pogorszeniu. Jedną z metod jej poprawiania jest instalowanie zasobników energii, tj. baterii akumulatorów, superkondensatorów czy kół zamachowych. Zasobniki energii są w stanie złagodzić dobową zmienność obciążenia, skompensować moc bierną i wyższe harmoniczne oraz zmniejszyć asymetrię obciążenia...
-
Towards Understanding the Health Aspects of the Processing of Lignocellulosic Fillers
PublikacjaHealth and safety issues should be addressed during the development and investigation of the industrial processes. In order to develop a sustainable process and fully evaluate its benefits and drawbacks for its optimization, it is crucial to determine its impact on the surrounding environment. This study aimed to assess the emission of volatile organic compounds during the modification of lignocellulosic fillers with passive dosimetry....
-
Instrumental measurement of odour nuisance in city agglomeration using electronic nose
PublikacjaThe paper describes an operation principle of odour nuisance monitoring network in a city agglomeration. Moreover, it presents the results of investigation on ambient air quality with respect to odour obtained during six-month period. The investigation was carried out using a network comprised of six prototypes of electronic nose and Nasal Ranger field olfactometers employed as a reference method. The monitoring network consisted...
-
Effective method of treatment of industrial effluents under basic pH conditions using acoustic cavitation – a comprehensive comparison with hydrodynamic cavitation processes
PublikacjaThe use of acoustic cavitation in advanced oxidation processes (AOPs) is a promising trend in research for treatment of industrial effluents. The paper presents the results of investigations on the use of acoustic cavitation aided by additional oxidation processes (ozonation/H2O2 oxidation/Peroxone/UV-C) for the treatment of effluents from the production of bitumens. Under these conditions, the total contaminant load, expressed...
-
Comparison of the Physical and Sensory Properties of Hybrid Citrus Fruit Jaffa® Sweetie in Relation to the Parent Fruits
PublikacjaIn the presented study, an overall Jaffa sweetie evaluation was made to find a correlation between Citrus grandis Osbeck × Citrus paradisi Macf. and its parent fruits’ (Citrus grandis Osbeck, Citrus paradisi Macf.) properties. Based on the sensory analysis, it was found that the taste and aroma of the new hybrid fruit are close to pummelo. By the use of chromatographic analysis, the selected monoterpenes present in the fruits were...
-
Multi-agent large-scale parallel crowd simulation with NVRAM-based distributed cache
PublikacjaThis paper presents the architecture, main components and performance results for a parallel and modu-lar agent-based environment aimed at crowd simulation. The environment allows to simulate thousandsor more agents on maps of square kilometers or more, features a modular design and incorporates non-volatile RAM (NVRAM) with a fail-safe mode that can be activated to allow to continue computationsfrom a recently analyzed state in...
-
A calibration model for gas sensor array in varying environmental conditions
PublikacjaAbstract: Gas-analyzing systems based on gas sensors, commonly referred to as electronic noses, are the systems which enable the recognition of volatile compounds in their working environment and provide the on-line results of analysis. The most commonly used type of sensors in such systems is semiconductor gas sensors. They are considered to be the most reliable in the long-term applications (more than 1 year), however,...
-
A calibration model for gas sensor array in varying environmental conditions
PublikacjaAbstract: Gas-analyzing systems based on gas sensors, commonly referred to as electronic noses, are the systems which enable the recognition of volatile compounds in their working environment and provide the on-line results of analysis. The most commonly used type of sensors in such systems is semiconductor gas sensors. They are considered to be the most reliable in the long-term applications (more than 1 year), however,...
-
Extraction and evaluation of gas-flow-dependent features from dynamic measurements of gas sensors array
PublikacjaGas analyzers based on gas sensors are the devices which enable recognition of various kinds of volatile compounds. They have continuously been developed and investigated for over three decades, however there are still limitations which slow down the implementation of those devices in many applications. For example, the main drawbacks are the lack of selectivity, sensitivity...
-
Preparation and characterization of asphaltene based adsorbents for gas-solid adsorption systems
PublikacjaThe dissertation presents results of the experimental research on asphaltene-based adsorbents (support coated with asphaltene layer) for gas-solid adsorption systems, with special reference to volatile organic compounds (VOCs) removal from gas streams. Analysis of gas adsorption properties revealed that asphaltenes isolated from oxidized bitumen have strong affinity toward VOCs. Interactions with target gas molecules, and selectivity...
-
Effective method of treatment of effluents from production of bitumens under basic pH conditions using hydrodynamic cavitation aided by external oxidants
PublikacjaUtilization of cavitation in advanced oxidation processes (AOPs) is a promising trend in research on treatment of industrial effluents. The paper presents the results of investigations on the use of hydrodynamic cavitation aided by additional oxidation processes (O3/H2O2/Peroxone) to reduce the total pollution load in the effluent from the production of bitumens. A detailed analysis of changes in content of volatile organic compounds...
-
Waste printer ink as modifier for natural rubber/carbon black composites: No haste, use waste
PublikacjaFrom a sustainability perspective, achieving a greener future with a minimal carbon footprint requires maximizing waste materials' reuse. The four pillars of satisfying customer demands are processing, price, properties, and performance. Along with such a global policy, this work seeks to utilize waste printer ink (WPI) as a source of carbon in combination with low- and high-surface carbon black (LCB and HCB, respectively) additives...
-
Electrohydrodynamic Flow Patterns in a Narrow Electrostatic Precipitator with Longitudinal Wire Electrode for Various Electrode Geometries
PublikacjaRecently narrow electrostatic precipitators (ESPs) have become a subject of interest because of their possible application in diesel engines. In this paper results of 2-dimensional (2D) Particle Image Velocimetry (PIV) measurements of the flow patterns in a narrow ESP for a various electrode geometries are presented. The PIV measurements were carried out in the observation plane that is perpendicular to the ESP duct. The ESP was...
-
Wykorzystanie słabych sygnałów, foresightu i ciągu zarządzania strategicznego w konfiguracji biznesu przyszłości
PublikacjaBurzliwość współczesnego otoczenia wyostrza zagadnienie przystosowania prowadzonej działalności gospodarczej do funkcjonowania w przyszłości. Do osiągnięcia sukcesu w biznesie przyszłości przyczynić się może wykorzystanie dostępnej już obecnie wiedzy. Na szczególną uwagę zasługuje teoria słabych sygnałów, metoda foresight oraz ciąg zarządzania strategicznego, które w połączeniu umożliwiają wypracowanie stanowiska w sprawie kształtu...
-
Raman miniaturised system for field applications
PublikacjaRaman spectroscopy is a powerful and versatile research technique with a broad range of potential applications, which includes laboratory studies, on-line industrial process monitoring and field measurements. Scope of the field applications includes environment monitoring, detection of dangerous or prohibited materials and rapid identification of unknown samples. It stimulates development of dedicated Raman measurement equipment...
-
Selective Harmonic Elimination PWM For a Cascaded Multi-level Inverter
PublikacjaThis paper deals with the selective harmonic elimination pulse width modulation (SHE-PWM) technique. This technique is used for the elimination of selected dominant low order harmonics in the multi-level inverter output voltage. The presence of these harmonics is the essential drawback of such kind of inverters; especially when it is used for the control of different AC drivers. The SHE-PWM is based...
-
Generation-recombination and 1/f noise in carbon nanotube networks
PublikacjaThe 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...
-
SrCe0.9In0.1O3-δ-based reversible symmetrical Protonic Ceramic Cell
PublikacjaIn-doped SrCe0.9In0.1O3-δ (SCI) perovskite-type oxide is utilized as the solid electrolyte, as well as a component, together with SrFe0.75Mo0.25O3-δ (SFM) compound, in the composite-type electrodes to construct symmetrical Protonic Ceramic Fuel Cells (PCFC). With good mutual stability of SCI and SFM at high temperatures in water vapor-containing reducing and oxidizing conditions, as well as sufficient ionic conductivity with high...
-
Nanotubular Oxide Layer Formed on Helix Surfaces of Dental Screw Implants
PublikacjaSurface modification is used to extend the life of implants. To increase the corrosion resistance and improve the biocompatibility of metal implant materials, oxidation of the Ti-13Nb- 13Zr titanium alloy was used. The samples used for the research had the shape of a helix with a metric thread, with their geometry imitating a dental implant. The oxide layer was produced by a standard electrochemical method in an environment of...
-
Influence of operation temperature instability on gas sensor performance
PublikacjaGas sensors based on the semiconducting metal-oxides, such as SnO2, have been found to be very useful for detecting a wide range of gases. The reversible interactions of the gas with the surface of the sensing layer made of semiconducting metal-oxides are responsible for changes of sensor resistance which is usually used as a measure of sensor response. Semiconductor gas sensors are commercially available and applied in numerous...
-
The Possibility of Phase Change Materials (PCM) Usage to Increase Efficiency of the Photovoltaic Modules
PublikacjaSolar energy is widely available, free and inexhaustible. Furthermore this source of energy is the most friendly to the environment. For direct conversion of solar energy into useful forms like of electricity and thermal energy, respectively photovoltaic cells and solar collectors are being used. Forecast indicate that the first one solution will soon have a significant part in meeting the global energy demand. Therefore it is...
-
THE PROPERTIES OF NANOSILVER – DOPED NANOHYDROXYAPATITE COATING ON THE Ti13Zr13Nb ALLOY
PublikacjaThe aim of this research was to study the properties of nanohydroxyapatite (nanoHAp) and nanohydroxyapatite, doped with nanosilver (nanoHAp/nanoAg), coatings obtained by an electrophoretic deposition process. The suspensions was prepared by dispersing 0.1 g of HAp nanopowder for nanoHAp coatings and 0.1 g of nanoHAp and 0.025 g nanoAg for nanoHAp/nanoAg coatings. The deposition was carried out for 1 min at 50 V voltage followed...
-
The influence of nanostructures size on V2O5 electrochemical properties as cathode materials for lithium ion battery
PublikacjaIn this paper, V2O5 nanostructures with a size depending on the annealing temperature are successfully synthesized by a sol-gel method. The crystal structure and morphology of samples are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), selected area electron diffraction (SEAD) and scanning electron microscopy (SEM), respectively. Electrochemical testing such...
-
Gas Detection Using Resistive Gas Sensors And Radial Basis Function Neural Networks
PublikacjaWe present a use of Radial Basis Function (RBF) neural networks and Fluctuation Enhanced Sensing (FES) method in gas detection system utilizing a prototype resistive WO3 gas sensing layer with gold nanoparticles. We investigated accuracy of gas detection for three different preprocessing methods: no preprocessing, Principal Component Analysis (PCA) and wavelet transformation. Low frequency noise voltage observed in resistive gas...
-
Propagation Characteristics of Partial Discharges in an Oil-Filled Power Transformer
PublikacjaPower transformers are among the most important assets in the power transmission and distribution grid. However, they suffer from degradation and possible faults causing major electrical and financial losses. Partial discharges (PDs) are used to identify the insulation health status and their degradation level. PDs are incipient, low-magnitude faults caused by localized dielectric breakdown. Those activities emit signals in many...
-
Innovative Bidirectional Isolated High-Power Density On-Board Charge for Vehicle-to-Grid
PublikacjaThis paper deals with developing and implementing a bidirectional galvanically isolated on-board charger of a high-power density. The power density of the new charger was 4 kW/kg and 2.46 kW/dm3, and the maximum efficiency was 96.4% at 3.4 kW. Due to the requirement to achieve a high-power density, a single-stage inverter topology was used. Regarding switching losses, due to the topology of the circuit with so-called hard switching,...
-
Evaluation of VSC Impact on Power System Using Adequate P-Q Capability Curve
PublikacjaRenewable energy sources, which are becoming increasingly popular, often use a voltage source converter (VSC) for connection to the power system. Assessing the effects of connecting such a source to the power system is essential to ensure the proper operation of the power system and the connected source. For this purpose, it is necessary to know the range of active and reactive power generation by the converter. The authors indicate...
-
Low-frequency noise in Au-decorated graphene–Si Schottky barrier diode at selected ambient gases
PublikacjaWe report results of the current–voltage characteristics and low-frequency noise in Au nanoparticle (AuNP)-decorated graphene–Si Schottky barrier diodes. Measurements were conducted in ambient air with addition of either of two organic vapors, tetrahydrofuran [(CH2)4O; THF] and chloroform (CHCl3), as also during yellow light illumination (592nm), close to the measured particle plasmon polariton frequency of the Au nanoparticle...
-
Ocena stopnia degradacji termicznej olejów jadalnych z wykorzystaniem techniki ultraszybkiej chromatografii gazowej
PublikacjaPod wpływem podwyższonej temperatury oleje jadalne ulegają procesowi degradacji termicznej. W tym przypadku ilość lotnych związków organicznych, charakteryzujących się dużą polarnością, występujących w olejach jadalnych jest większa. Zmiany składu olejów jadalnych mogą stanowić zagrożenie dla zdrowia człowieka. Obecnie istnieje możliwości wykorzystania techniki ultraszybkiej chromatografii gazowej do oceny stopnia degradacji olejów...
-
Kontrola procesowa za pomocą technik czujnikowych nowych metod selektywnego oczyszczania biogazu ze związków uciążliwych zapachowo
PublikacjaW obecnym czasie dużą uwagę zwraca się na opracowanie efektywnej technologii oczyszczania biogazu do gazu wysokometanowego. Głównym celem rozprawy doktorskiej było opracowanie ekonomicznie opłacalnych absorbentów do efektywnego oczyszczania strumieni biogazu z substancji uciążliwych zapachowo. Procesy absorpcji fizycznej prowadzono z wykorzystaniem zaprojektowanych i otrzymanych dotąd jeszcze nie publikowanych sorbentów na bazie...
-
Treatment of bitumen post oxidative effluents by sulfate radicals based advanced oxidation processes (S-AOPs) under alkaline pH conditions
PublikacjaSulfate radicals based Advanced Oxidation Processes (S-AOPs), namely Persulfate and peroxymonosulfate, were used for the treatment of post oxidative effluents from a production of petroleum bitumens under alkaline pH. Studies on the identification and monitoring of the volatile organic compounds (VOCs) along with COD, BOD and sulfide ions reduction were performed. Persulfate with a ratio between the oxygen from the oxidant and...
-
Exhaled breath analysis by resistive gas sensors
PublikacjaBreath analysis has attracted human beings for centuries. It was one of the simplest methods to detect various diseases by using human smell sense only. Advances in technology enable to use more reliable and standardized methods, based on different gas sensing systems. Breath analysis requires the detection of volatile organic compounds (VOCs) of the concentrations below individual ppm (parts per million). Therefore, advanced detection...
-
α-Pinene, 3-carene and d-limonene in indoor air of Polish apartments: The impact on air quality and human exposure
PublikacjaMonoterpenes are among most ubiquitous volatile organic compounds (VOCs) to be detected in indoor air. Since the quality of indoor air is considered important for inhabitants' well-being, the present study aimed at investigating impact of human activity on levels of selected monoterpenes applying passive sampling technique followed by thermal desorption and gas chromatography coupled mass spectrometry. One of the objectives of...
-
A fast start-up of the organotrophic anammox process inoculated with constructed wetland sediment
PublikacjaOrganotrophic anaerobic ammonium oxidation (anammox) bacteria can utilize small volatile fatty acids with nitrate as electron acceptors with less energy consumption and no biomass production. To achieve a faster and stable start-up of organotrophic anammox process, in this study, the growth of organotrophic anammox bacteria seeded from hybrid constructed wetland (CW) sediment under different TOC/TN ratios and different chloramphenicol...
-
Mass spectrometric identification of 13C-Labeled metaboloites during anaerobic propanoic acid oxidation
PublikacjaBiowaste digestion is a possibility to gain biogas as a renewable fuel source. However, the anaerobic food chain may be disrupted by, e.g., substrate overload or by inhibitors, leading to the accumulation of volatile fatty acids (VFAs), predominantly of propanoic acid (PA). VFA Accumulation may cause a rapid pH decrease, less biogas production, or even a total inhibition. To maintain high biogas productivity or to prevent a collapse...
-
Mass Spectrometric Identification of 13C-Labeled Metabolites DuringAnaerobic Propanoic Acid Oxidation
PublikacjaBiowaste digestion is a possibility to gain biogas as a renewable fuel source. However, the anaerobic food chain may be disrupted by, e.g., substrate overload or by inhibitors, leading to the accumulation of volatile fatty acids (VFAs), predominantly of propanoic acid (PA). VFA Accumulation may cause a rapid pH decrease, less biogas production, or even a total inhibition. To maintain high biogas productivity or to prevent a collapse...
-
Deep eutectic solvents – Ideal solution for clean air or hidden danger?
PublikacjaThe industrial sector is one of the fastest-growing sources of greenhouse gases, due to its excessive energy consumption to meet the rapidly growing demand for energy-intensive products. The use of deep eutectic solvents (DESs) has been studied extensively in order to cope with these harmful gases, but their usage can be an issue in respect to ecological reasons. Do deep eutectic solvents harm the atmosphere? Yes, these solvents...
-
Detekcja i lokalizacja nieprzewodzenia tranzystorów falownika napięcia na podstawie analizy prądu obciążenia
PublikacjaPrzedstawiono nową metodę detekcji i lokalizacji nieprzewodzenia tranzystorów w falownikach napięcia zasilających silniki indukcyjne małej mocy. Metoda bazuje na monitorowaniu wartości dwóch sygnałów dia-gnostycznych. Pierwszy z nich, wskaźnik braku przepływu prądu, wykorzystano w celu detekcji uszkodzeń. Drugi, stosunek wartości średniej prądu do wartości średniej bezwzględnej, zawiera informacje umożliwiające lokalizację uszkodzonych...
-
Assessment of organic coating degradation via local impedance imaging
PublikacjaThe paper presents a new approach to organic coating condition evaluation at micrometer scale using localized impedance measurements. It is based on atomic force microscopy (AFM) in contact mode. Impedance is measured between conductive AFM tip and metal substrate covered with organic coating. A single-frequency voltage perturbation signal is applied between the electrodes and current response signal is registered. As the tip is...
-
Behavior of residual current devices at frequencies up to 50 kHz
PublikacjaThe use of residual current devices (RCDs) is obligatory in many types of low-voltage circuits. They are devices that ensure protection against electric shock in the case of indirect contact and may ensure additional protection in the case of direct contact. For the latter purpose of protection, only RCDs of a rated residual operating current not exceeding 30 mA are suitable. Unfortunately, modem current-using equipment supplied...
-
A novel dual-band rectifier circuit with enhanced bandwidth for RF energy harvesting applications
PublikacjaIn recent years, a rapid development of low-power sensor networks, enabling machine-to-machine communication in applications such as environmental monitoring, has been observed. Contemporary sensors are normally supplied by an external power source, typically in a form of a battery, which limits their lifespan and increases the maintenance costs. This problem can be addressed by harvesting and converting ambient RF energy into...
-
In Vitro Biological Characterization of Silver-Doped Anodic Oxide Coating on Titanium
PublikacjaDespite the high biocompatibility and clinical effectiveness of Ti-based implants, surface functionalization (with complex osteointegrative/antibacterial strategies) is still required. To enhance the dental implant surface and to provide additional osteoinductive and antibacterial properties, plasma electrolytic oxidation of a pure Ti was performed using a nitrilotriacetic acid (NTA)-based Ag nanoparticles (AgNP)-loaded calcium–phosphate...
-
Methods of trend removal in electrochemical noise data – overview
PublikacjaIn this paper we shall review popular methods of trend removal from electrochemical noise time records. The basic principles of operation of the six most popular methods are explained. The proposed methods are: high - pass filtering, Moving Average Removal, polynomial detrending, wavelet detrending, Empirical Mode Decomposition and Variational Mode Decomposition. Estimation of trend removal quality...
-
Role of surface recombination in perovskite solar cells at the interface of HTL/CH3NH3PbI3
PublikacjaIn order to achieve the highest performance of organometal trihalide perovskite solar cells, it is required to recognize the dominant mechanisms which play a key role in a perovskite material. In the following studies, we have focused on the interfacial recombination between the hole transporting layer (HTL) and the perovskite CH3NH3PbI3 in solar cell devices with p–i–n architecture. It has been shown that Cu:NiOx : used as HTL...
-
Testing sensitivity of A-type residual current devices to earth fault currents with harmonics
PublikacjaIn many applications, modern current-using equipment utilizes power electronic converters to control the consumed power and to adjust the motor speed. Such equipment is used both in industrial and domestic installations. A characteristic feature of the converters is producing distorted earth fault currents, which contain a wide spectrum of harmonics, including high-order harmonics. Nowadays, protection against electric shock in...
-
Infrared techniques for natural convection investigations in channels between two vertical, parallel, isothermal and symmetrically heated plates
PublikacjaThe effect of the gap width between two symmetrically heated vertical, parallel, isothermal plates on intensity of natural convective heat transfer in a gas (Pr = 0.71) was experimentally studied using the balance and gradient methods. In the former method heat fluxes were determined based on measurements of the voltage and electric current supplying the heaters placed inside the walls. In the latter, heat fluxes were calculated...
-
The excitation controller with gain scheduling mechanism for synchronous generator control
PublikacjaThe power systems, including the synchronous generators and power systems networks, are complex nonlinear systems with configuration and parameters which change through time. That leads to electromechanical oscillations occurring in that system. Thus synchronous generator excitation controller must be capable of providing appropriate stabilization signal over broad range of operating conditions and disturbances. In this paper,...
-
Switched-capacitor DC-DC converters in arbitrary switching mode - topologically derived resistive models based on incremental graph approach.
PublikacjaIn the preceding paper we reviewed some of modeling approaches aimed at systematic formulation and solution of switched capacitor DC-DC converters. In our review, special attention was paid to computationally efficient and mathematically elegant methods. In so doing we had tried to demonstrate the virtues of unified Incremental Graph (IG) approach. Incremental Graph is, in concept, a tool originally created for analysis and synthesis...
-
Inhibition of T-type calcium channel disrupts Akt signaling and promotes apoptosis in glioblastoma cells.
PublikacjaGlioblastoma multiforme (GBM) are brain tumors that are exceptionally resitant to both radio- and chemotherapy regimens and novel approaches to treatment are needed. T-type calcium channels are one type of low voltage-gated channel (LVCC) involved in embryonic cell proliferation and differentiation; however they are often over-expressed in tumors, including GBM. In this study, we found that inhibition of T-type Ca channels in GBM...