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Search results for: physico-chemical parameters
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Ab initio chemical kinetics of Isopropyl acetate oxidation with OH radicals
PublicationGlobal reactivity descriptors of isopropyl acetate (IPA) and thermo-kinetic aspects of its oxidation via OH radicals have been studied. Transition state theory (TST) was utilized to estimate the bimolecular rate constants. Ten oxidation pathways have been investigated, and all of them are exothermic. The potential energy diagram has been sketched using different pre- and post-reactive complexes for all reaction pathways. Rate coefficient...
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Experimental Evaluation of ND: YAG Laser Parameters and Sample Preparation Methods for Texturing Thin AISI 316L Steel Samples
PublicationIn mechanical and material engineering, the effect of laser texturing depends on many factors besides device specification, primarily the properties of the materials being processed, and, secondly, the preparation of the sample. Laser texturing of thin (<5 mm) samples is mostly performed utilizing short-pulse lasers, but depending on the power of the laser beam, the process can also be performed by using continuous operation lasers....
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Impact of Cultivation Conditions, Ethylene Treatment, and Postharvest Storage on Selected Quality and Bioactivity Parameters of Kiwifruit “Hayward” Evaluated by Analytical and Chemometric Methods
PublicationOrganic, semiorganic, and conventional “Hayward” kiwifruits, treated with ethylene for 24 h and stored during 10 days, were assessed by UV spectrometry, fluorometry, and chemometrical analysis for changes in selected characteristics of quality (firmness, dry matter and soluble solid contents, pH, and acidity) and bioactivity (concentration of polyphenols via Folin-Ciocalteu and p-hydroxybenzoic acid assays). All of the monitored...
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FROM HARVESTING TO DISTILLATION - EFFECT OF ANALYTICAL PROCEDURES ON THE YIELD AND CHEMICAL COMPOSITION OF RHODODENDRON TOMENTOSUM (LEDUM PALUSTRE) ESSENTIAL OIL
PublicationRhododendron tomentosum possesses the anti-inflammatory, analgesic and antimicrobial properties, determined by the chemical composition of its essential oil. The effects of place (Miszewko, Lubichowo) and time of harvesting (June, November) as well as drying (air-drying, oven-drying, freeze-drying) and isolation (in Deryng, Clevenger and Likens-Nickerson apparatus) procedures on the yield and quality of R. tomentosum essential...
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The impact of interactions between polyphenolic antioxidants on the redox-related chemical and biological properties of their mixtures – the extension of food synergy concept.
PublicationThe results of studies indicate that chemopreventive efficiency of isolated phytochemicals is lower than that of polyphenol-rich foods. This discrepancy has been ascribed to the food synergy concept that assumes additive or even synergistic influence of different food ingredients on human health. The results presented in the dissertation made it possible to propose an alternative and innovative explanation of these observations. The...
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Structure and optical parameters of Eu doped tellurium oxide thin films prepared by reactive magnetron sputtering method
PublicationIn this work the structural properties and photoluminescence of tellurium dioxide thin films doped by europium were described. Thin films were deposited by magnetron sputtering method and simultaneously heated at 200 °C. Presence of Eu ions and their valence states was confirmed by X-ray photoemission spectroscopy measurements. The structure of the films as well as the influence of europium dopant on crystalline structure of the...
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Low-cost and reliable geometry scaling of compact microstrip couplers with respect to operating frequency, power split ratio, and dielectric substrate parameters
PublicationA technique for rapid re-design of miniaturised microstrip couplers with respect to operating conditions as well as material parameters of the dielectric substrate is proposed. The dimension scaling process is based on a set of pre-optimised reference designs, obtained for an equivalent circuit model of the coupler at hand. The reference designs are utilised to construct an inverse surrogate model which – upon suitable correction...
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The In-Depth Studies of Pulsed UV Laser-Modified TiO2 Nanotubes: The Influence of Geometry, Crystallinity, and Processing Parameters
PublicationThe laser processing of the titania nanotubes has been investigated in terms of morphology, structure, and optical properties of the obtained material. The length of the nanotubes and crystallinity, as well as the atmosphere of the laser treatment, were taken into account. The degree of changes of the initial geometry of nanotubes were checked by means of scanning electron microscopy, which visualizes both the surface and the cross-section....
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Model studies to identify input parameters of an algorithm controlling electric supply/consumption process by underground iron ore enterprises
PublicationPurpose is the development of the research format of a mathematical model to select and assess input parameters of an algorithm controlling distribution of electric energy flows in the monitoring structure of electricity supply/ consumption by using equipment of mining enterprises engaged in underground iron ore raw materials extraction. Methods. The analytical research involved a theory of random processes adapted to the real...
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Novel Adaptive Method for Data Streams Allocation Based on the Estimate of Radio Channel Parameters in Heterogeneous WBAN Network
PublicationThe new adaptive method for data streams allocation in heterogeneous Wireless Body Area Networks and meas-urement equipment is presented. The results obtained using the developed method compared with the selected algorithms likely to be used in those networks. The pro-posed adaptive data streams allocation method based on radio channel parameters makes it even twice as efficient to use in terms of resources usage in a WBAN heterogeneous...
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Mater-Bi/Brewers’ Spent Grain Biocomposites—Novel Approach to Plant-Based Waste Filler Treatment by Highly Efficient Thermomechanical and Chemical Methods
PublicationThermoplastic starch (TPS) is a homogenous material prepared from native starch and water or other plasticizers subjected to mixing at a temperature exceeding starch gelatinization temperature. It shows major drawbacks like high moisture sensitivity, poor mechanical properties, and thermal stability. To overcome these drawbacks without significant cost increase, TPS could be blended with bio-based or biodegradable polymers and...
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The Influence of Tool Shape and Process Parameters on the Mechanical Properties of AW-3004 Aluminium Alloy Friction Stir Welded Joints
PublicationThe purpose of the following study was to compare the effect of the shape of a tool onthe joint and to obtain the values of Friction Stir Welding (FSW) parameters that provide the bestpossible joint quality. The material used was an aluminium alloy, EN AW-3004 (AlMn1Mg1). To theauthors’ best knowledge, no investigations of this alloy during FSW have been presented earlier. Fivebutt joints were made with a self-developed, cylindrical,...
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THEORETICAL AND EXPERIMENTAL INVESTIGATION OF THIN-WALLED BEARING SHELL’S DESIGN PARAMETERS AND ASSEMBLY CONDITIONS ON THE HOLDING TORQUE INSIDE A HOUSING BORE OF A CONNECTING ROD
PublicationThe aim of the work was the experimental and theoretical evaluation of the influence of the most important parameters determining the holding torque of a thin-walled bearing shell inside a housing bore of a connecting rod. The main investigated parameters were defned by authors experience in this feld. In the frst stage of research, a special test stand was designed in order to allow measuring the real values of the friction torque...
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The influence of chemical composition of amide block on the thermal properties and structure of terpoly(ester-b-ether-b-amide) elastomers
PublicationMultiblock terpolymers-(PBT-b-PTMO-b-PA12,10)(n)- constituting the polymer systems, in which one of the three blocks (PBT) does not dissolve in PA12,10 block (hard phase) and, depending on its molecular weight is slightly soluble in PTMO block (soft phase), have been obtained. The DSC method was applied to investigate the thermal properties of these polymers and it was found that PBT block acts as an element that produces stiffness...
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Influence of parameters of deep grinding on nanohardness and surface roughness of C45 steel
PublicationPrzedstawiono wyniki badań wpływu głębokości współbieżnego szlifowania powierzchni płaskich na chropowatość i nanotwardość warstwy wierzchniej stali C45 o strukturze ferrytyczno-perlitycznej i średniej wielkości ziarna 20 μm. Dla wszystkich wartości głębokości szlifowania uzyskano znaczny wzrost twardości warstwy wierzchniej przedmiotu obrabianego.
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Methodology for assessing the lighting of pedestrian crossings based on light intensity parameters
PublicationOne of the possible preventive measures that could improve safety at crossings is to assess the state of illumination of the lighting installation located in the transition area for pedestrians. The City of Warsaw has undertaken to comprehensively assess the pedestrian crossings to determine the level of road safety and the condition of lighting. The lighting conditions related to pedestrian crossings without traffic lights in...
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The Influence of Silica Fume on the Mechanical and Thermal Parameters of Portland Cement Concretes
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An integrated periodic structure in Silicon technology to improve power amplifier parameters
PublicationNowa zintegrowana struktura periodyczna wykonana w technologii krzemowej została wprowadzona do międzystopniowego układu dopasowania wzmacniacza mocy. Dzięki temu stwiedzono poprawę większości charakterystyk wzmacniacza, jak również własności filtrujących (tłumienie harmonicznych).
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Simulation of electric hearing - influence of simulation parameters on quality of output signal
PublicationW środowisku programistycznym Matlab stworzono symulację słuchu elektrycznego pacjenta implantowanego. W symulacji zastosowano algorytm przetwarzania wykorzystywany w komercyjnych systemach implantów ślimakowych - CIS (Continuous Interleaved Sampling). W pracy zbadano wpływ ilości kanałów, jak i innych parametrów sygnałów wyjściowych przy zastosowaniu sygału mowy jako sygnału wejściowego symulacji.
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The influence of selected parameters of idd on vibrations of contact in ac hybrid breaker
PublicationWzrost mocy systemów zasilania na statkach wymaga poszukiwania nowych rozwiązań wyłączników dc oraz ac. Od kilku lat trwają prace nad modelowaniem ultra szybkiego hybrydowego wyłącznika prądu. Czas wyłączenia prądu wyłącznika zależy od wielu parametrów. W pracy przedstawiono wyniki badań eksperymentalnych i symulacyjnych wyłącznika ze szczególnym uwzględnieniem rezystancji zestyku.
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Selection of SOM parameters for the needs of clusterization of data obtained by interferometric methods
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Reliability of UAVs in Fire Services Operations. Tests and Measurements of Selected Parameters
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Determination of operational load parameters of dredge pumps under dredging operations
PublicationArtykuł przedstawia propozycję metody określania parametrów rozkłądów eksploatacyjnych obciążeń, jednego z najważniejszych odbiorników energii mechanicznej na pogłębiarkach - pomp pogłębiarskich (gruntowych). Metoda wykorzystująca wyniki własnych badań eksploatacyjnych, odnosi się do dwóch podstawowych stanów eksploatacji pomp pogłębiarskich, a mianowicie do stanu nazywanego załadunkiem ładowni gruntowej (pogłebiarki lub szalandy)...
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Methods of material parameters identification for isotropic damage in viscoplastic flow conditions
PublicationW pracy zaprezentowano trzy metody identyfikacji parametrów materiałowych dla izotropowego zniszczenia w warunkach lepkoplastycznego płynięcia. Przedstawiono wyniki identyfikacji dla dwóch stopów aluminium, które następnie zweryfikowano porównując wyniki symulacji numerycznych z wynikami eksperymentalnymi.
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Use of Satellite Data in Monitoring of Hydrophysical Parameters of the Baltic Sea Environment
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Optimization of Parameters in Macromolecular Potential Energy Functions by Conformational Space Annealing
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Maximum A Posteriori Bayesian Estimation of Chromatographic Parameters by Limited Number of Experiments
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Global Optimization-Based Method for Deriving Intermolecular Potential Parameters for Crystals
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The influence of sampling parameters on accuracy of capacitance measurement in the method based on DSP.
PublicationW artykule przedstawiono metodę pomiaru parametrów impedancyjnych bazującą na próbkowaniu sygnałów pomiarowych i DSP. Przeanalizowano wpływ głównych źródeł niepewności i błędów na dokładność pomiaru pojemności. Zawarto analizę dla następujących parametrów: niesynchroniczne próbkowanie sygnałów pomiarowych (napięciowego i prądowego), rozdzielczość przetwornika a/c i ilość zbieranych próbek. Załączono wyniki symulacji.
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Cavitation erosion of steels processed by CO2 laser beams of various parameters.
PublicationPrzedstawiono wpływ parametrów przetapiania stali za pomocą wiązki lasera CO2 na jej własności kawitacyjne. Do badań użyto stali 45, 2H13 i OH18N9. Wyniki badań wskazują na znaczny wpływ parametrów przetapiania na poziom odporności kawitacyjnej stali.
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Estimation of optical parameters of highly scattering materials by time-of-flight spectroscopy.
PublicationPrzedstawiono metody wyznaczania podstawowych parametrów materiałów silnie rozpraszających światło na podstawie pomierzonego rozkładu czasu przelotu krótkich impulsów laserowych. W algorytmie wykorzystano metodę Monte Carlo i metodę dyfuzji do opisu propagacji światła. Oszacowano dokładność oszacowywania tych parametrów.
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Estimation of the short-term predictor parameters of speech under noisy conditions
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Recreation of Voltage Fluctuation Using Basic Parameters Measured in the Power Grid
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Influence of material properties of charge on electrical parameters of induction heating setup
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Modeling of Heat Source Based on Parameters of Electron Beam Welding Process
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Influence of 8-Hour Road Transportation on Selected Physiological Parameters in Horses
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Influence of ducting geometry on working parameters of pipe type hydraulic turbines
PublicationMała energetyka wodna. Omówiono własności użytkowe - głównie, sprawność i adaptacyjność - uzyskiwane poprzez rozwiązania układów turbinowych stosowanych w obszarze zagospodarowywania piętrzeń niskospadowych. Wskazano przyczyny od których te własności zależą. Pokazano też przykład rozwiązania o pożądanych własnościach dla zagospodarowywania obiektów w mało atrakcyjnym ekonomicznie obszarze piętrzeń najniższych.
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DESIGNING OF PARKING SPACES TAKING INTO ACCOUNT THE PARAMETERS OF DESIGN VEHICLES IN RUSSIA
PublicationNowadays, in all the cities, there is an acute problem of a lack of parking spaces. The number of vehicles are becoming more and more larger, not only in megacities, but in small cities of the country, as well and there are no more parking places - the pace of solving the problem is several times slower than the rate of the transport growth among the citizens. The article is dedicated to the determination of the optimum sizes parking...
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The Analysis of Working Parameters Decrease in Photovoltaic Modules as a Result of Dust Deposition
PublicationThe aspect of dust accumulation on the surface of photovoltaic (PV) modules should be thoroughly understood in order to minimize possible obstacles affecting energy generation. Several elements affect the amount of pollutant gathered on the surface of a solar device, mainly its localization, which is irreversibly linked to factors such as annual rainfall, occasional snow coverage, or, in a dry climate, increased blow of dust during...
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Determination of Fe2+/Fe3+ mole ratio based on the change of precursor lattice parameters of wustite based iron catalysts for the ammonia synthesis
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The Concept of a Methodology for Selecting the Optimal Parameters of Heat Received from a Nuclear Power Plant Operating in a Partial Cogeneration Mode
PublicationThe paper presents the concept of the objective function which is to allow the selection of optimal parameters of the district heating system using a nuclear power plant operating in partial cogeneration mode. The concept is based on research carried out a number of years ago. The size of annual expenses was proposed as the objective function, which allows to compare the operation of a nuclear power plant in partial cogeneration...
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Chemical Composition of Atmospheric Air in Nemoral Scots Pine Forests and Submountainous Beech Forests: The Potential Region for the Introduction of Forest Therapy
PublicationStudies show that forests are one of the main recreational destinations. This can be explained by their beneficial effects on the health of their visitors, which can be attributed to compounds from the terpene group. The aim of this research was to determine the chemical composition of air in the interiors of Nemoral Scots pine forests and submountainous beech forests, with the determination of compounds of the terpene group. Samples...
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Application of Multivariate Adaptive Regression Splines (MARSplines) for Predicting Hansen Solubility Parameters Based on 1D and 2D Molecular Descriptors Computed from SMILES String
PublicationA new method of Hansen solubility parameters (HSPs) prediction was developed by combining the multivariate adaptive regression splines (MARSplines) methodology with a simple multivariable regression involving 1D and 2D PaDEL molecular descriptors. In order to adopt the MARSplines approach to QSPR/QSAR problems, several optimization procedures were proposed and tested. The effectiveness of the obtained models was checked via standard...
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The effect of Fe on chemical stability and oxygen evolution performance of high surface area SrTix-1FexO3-δ mixed ionic-electronic conductors in alkaline media
PublicationDevelopment of environmentally friendly, high performing oxygen evolution reaction (OER) catalysts is an important research challenge. In this work, iron doped strontium titanates with a general formula SrTi1-xFexO3-δ (x = 0.35, 0.50, 0.70, 0.90, and 1.00) denoted as STFx, were synthesized via a solid state reaction technique and characterized in terms of oxygen evolution reaction electrocatalysis in an alkaline electrolyte (0.1...
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Determination of Thermophysical Parameters Involved in The Numerical Model to Predict the Temperature Field of Cast-In-Place Concrete Bridge Deck
PublicationThe paper dealswith a concept of a practical computationmethod to simulate the temperature distribution in an extradosed bridge deck. The main goal of the study is to develop a feasible model of hardening of concrete consistent with in-situ measurement capabilities. The presented investigations include laboratory tests of high performance concrete, measurements of temperature evolution in the bridge deck and above all, numerical...
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Chemical, Aroma and Pro-Health Characteristics of Kaffir Lime Juice—The Approach Using Optimized HS-SPME-GC-TOFMS, MP-OES, 3D-FL and Physiochemical Analysis
PublicationThe study aimed to provide the chemical, aroma and prohealth characteristics of the kaffir lime juice. A procedure using solid-phase microextraction with gas chromatography (SPME-GC-TOFMS) was optimized and validated for the determination of terpenes of kaffir lime. Main physicochemical parameters: pH, vitamin C, citric acid and °Brix were evaluated. Micro- and macro elements were determined using microwave plasma optic emission...
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Analysis of Positioning Error and Its Impact on High Frequency Performance Parameters of Differential Signal Coupler of Differential Signal Coupler
PublicationThis paper presents the analysis of the effect of differential signal coupler positioning accuracy on its high frequency performance parameters for contact-less high speed chip-to-chip data transmission on PCB application. Our considerations are continuation of the previous works on differential signal coupler concept, design methodology and analysis for high speed data transmission monitoring presented in [1, 2]. The theoretical...
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Alkali-activated slag (AAS) and OPC-based composites containing crumb rubber aggregate: Physico-mechanical properties, durability and oxidation of rubber upon NaOH treatment
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Influence of Hydrogenation on Morphology, Chemical Structure and Photocatalytic Efficiency of Graphitic Carbon Nitride
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A Comprehensive Review on Shilajit: What We Know about Its Chemical Composition
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