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Real-Time Volatilomics: A Novel Approach for Analyzing Biological Samples
PublikacjaThe use of the ‘omics techniques in environmental research has become common-place. The most widely implemented of these include metabolomics, proteomics, genomics, and transcriptomics. In recent years, a similar approach has also been taken with the analysis of volatiles from biological samples, giving rise to the so-called ‘volatilomics’ in plant analysis. Developments in direct infusion mass spectrometry (DI-MS) techniques have...
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Modelling the impact of the agricultural holdings and land-use structure on the quality of inland and coastal waters with an innovative and interdisciplinary toolkit
PublikacjaThe changes taking place in the marine coastal zones are extremely important, as about 40% of the human population currently lives in the coastal areas (within 100 kilometres of the coastline) increasing anthropogenic pressure on the marine ecosystems. Agriculture is a significant source of nutrients to the marine environment that increase hypoxia, eutrophication and may pose a threat to the services provided by ecosystems. In...
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Multi-Beam Antenna for Ka-Band CubeSat Connectivity Using 3-D Printed Lens and Antenna Array
PublikacjaIn this paper, the design of a passive multi-beam lens antenna is proposed for the CubeSat space communication system as an alternative application of a 2-D microstrip antenna array that has originally been designed for a 39 GHz 5 G MU-MIMO system. The half-ellipsoid lens is 3-D printed using stereolithography (SLA) technology. The antenna prototype is capable of selecting the main beam between 16 different directions with a gain...
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Automatic sound source localization in disturbing conditions using acoustic vector sensors
PublikacjaA concept, practical realization and applications of a passive acoustic radar to automatic localization and tracking of sound sources in disturbing conditions were presented in the paper. The device consists of the new kind of multichannel miniature sound intensity sensors and a group of digital signal processing algorithms. The sensitivity of the realized acoustic radar was examined in free sound field. Several kinds of sound...
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Semi complex navigation with an active optical gesture sensor
PublikacjaThis paper presents the methods of diversified touchless interactions between a user and a mobile platform utilizing the optical gesture sensor. The sensor uses 8 photodiodes to measure the reflected light in the active mode (using embedded LEDs) or it measures shadows caused by fingers in the passive mode. Several algorithms were implemented: automatic mode switching, adaptive illumination level compensation, resolution improvements...
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Implementation of DIFAR Processing in ASW Dipping Sonar
PublikacjaThis paper presents the implementation of the signal processing algorithm used by buoy DIFAR (Directional Frequency Analysis and Recording), that is fully operational on Polish Navy anti-submarine warfare (ASW) helicopters and ships, applied to dipping sonars for detection and tracking of submarines. The development of the DSP algorithms was a part of the modernization of sonars conducted at the Gdansk University of Technology....
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Capillary pumped loop as a tool for collecting large heat fluxes from electronic devices on warships
PublikacjaThe combat potential of future warships will be directly related to the use of modern electronic devices being parts of advanced systems, such as, for instance, radar systems, fire aiming systems, fire detection systems, electric drive systems, and even electronic and radio-electronic weaponry, railguns and lasers, installed on these warships. The capacity and functionality of these devices is continually increasing, at decreasing...
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Model matematyczny przełączalnego silnika reluktancyjnego w układzie napędowym
PublikacjaPrzedstawiono sposób modelowania i opracowany model matematyczny przełączalnego silnika reluktancyjnego w układzie napędowym wyprowadzony z metody energetycznej Lagrange'a. Dokonano odpowiedniego podziału przełączalnego silnika reluktancyjnego na elementy skupione, sformułowano funkcje stanu elementów zachowawczych i rozpraszających. Wyznaczono funkcję Lagrange'a i funkcję dyssypacji Rayleigha we współrzędnych uogólnionych oraz...
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HMSE: A tool for coupling MODFLOW and HYDRUS-1D computer programs
PublikacjaA new software HMSE has been developed to facilitate external coupling between two well-known programs for subsurface flow modeling: MODFLOW-2005 (saturated zone flow) and HYDRUS-1D (unsaturated zone flow). Two coupling schemes have been implemented. In the first case the groundwater recharge flux is calculated by HYDRUS-1D assuming a fixed water table position and then passed to MODFLOW input files. In the second case the water...
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Pervaporation of volatile organohalogen compounds throughpolydimethylsiloxane membrane
PublikacjaThe objective of this work was to apply dense polymeric membranes for pervaporation of tetrachloroethene from aqueous solution. Three membranes were evaluated: polydimethylsiloxane (PDMS-PV1 and PDMSPV2) membranes, and a PDMS with ZSM-5 zeolite filled (PERVAP-1070) membrane. The effect of feed composition on flux and selectivity was also investigated. Tested membranes showed good properties in the separation of tetrachloroethylene,...
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ARRAY OF MINIJETS – THERMAL AND HYDRAULIC PHENOMENA IN BOUNDARY LAYER
PublikacjaPresented work considers flow and thermal phenomena occurring in the system consisting of minijets array and heated with constant heat flux surface. Numerical analyses, based on the mass, momentum and energy conservation laws, were conducted. Focus was placed on the proper model construction, in which turbulence and boundary layer modelling was crucial. Calculations were done for various mass flow rates. The main calculations were...
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Release and Transport of Toxic, Mobile Organic Compounds (Formaldehyde and Phenols) on an Arctic Glacier
PublikacjaAs a result of current deglaciation, the chemical cycles of many compounds, including toxic formaldehyde and phenols, are changing. However, the processes by which these chemicals are released have yet to be studied in situ. Here, we quantify fluxes of HCHO and phenols in a glacial catchment within one summer season, obtaining a net release from the glacier of 0.106 · 106 g formaldehyde and 0.255 · 106 g phenols, which can be interpreted...
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Finite Element Method Applied in Electromagnetic NDTE: - A Review
PublikacjaThe paper contains an original comprehensive review of finite element analysis (FEA) applied by researchers to calibrate and improve existing and developing electromagnetic non-destructive testing and evaluation techniques, including but not limited to magnetic flux leakage (MFL), eddy current testing, electromagnetic-acoustic transducers (EMATs). Premium is put on the detection and modelling of magnetic field, as the vast majority...
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Numerical simulation of natural convection of Glycol-Al2O3 nanofluids from a horizontal cylinder
PublikacjaThis paper deals with natural convection around a circular cylinder with constant heat flux in a cavity using computational fluid dynamics. As fluids ethylene glycol and a mixture of ethylene glycol with Al2O3 nanoparticles (mass concentrations of nanoparticles: 0.1% and 1%) are chosen. Rayleigh number ranges from 3104 to 3105. The nanofluids are modeled with single-phase approach. For the investigated range of nanoparticle concentration, the...
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Flow Boiling in Minigap in the Reversed Two-Phase Thermosiphon Loop
PublikacjaThe paper presents the results of experimental investigations of a model of a heat exchanger featuring a minigap, which is perceived as an evaporator for an inverted thermosiphon. The system works with a single component test fluid. The tested evaporator generates pumping power in the test loop in a way similar to the mammoth pump. The tests regarded a module of the heat exchanger, consisting of a hot leg and a cold leg with the...
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A subdomain model for armature reaction field and open‐circuit field prediction in consequent pole permanent magnet machines
PublikacjaIn this paper, the machine quantity, such as electromagnetic torque, self and mutual inductances, and electromotive force, is analytically calculated for non-overlapping winding consequent pole slotted machine for open-circuit field and armature reaction. The sub-domain approach of (2-D) analytical model is developed using Maxwell's equations and divide the problem into slots, slot-openings, airgap and magnets region, the magnet...
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Analiza wydajności kolektora słonecznego przeznaczonego dla systemu ogrzewania budynku o niskim zapotrzebowaniu na ciepło
PublikacjaNiniejsza praca przedstawia wyniki badań numerycznych kolektora słonecznego, przeznaczonego dla budynków o niskim zapotrzebowaniu na ciepło. W pracy przedstawiono nowatorską koncepcję kolektora słonecznego o obniżonej wydajności, niskich kosztach wykonania oraz wykorzystującego istniejące elementy konstrukcji przekryć budynku. Istotną zaletą kolektora jest brak ingerencji w architekturę zewnętrzną budynku. Za pomocą symulacji numerycznej...
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Concentrations of monoaromatic hydrocarbons in the air of the underground car park and individual garages attached to residential buildings
PublikacjaThe paper describes the characteristics of a two-level underground car park and three individual garages attached to residential buildings, differing by the resident utilization habits, located in North Poland (Tri-City agglomeration area). The strategy of collecting the analyte samples from air in mentioned enclosed areas, concerning the determination of benzene, toluene, ethylbenzene, o-xylene and p,m-xylenes (BTEX) concentrations...
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A new construction of shell-and-tube heat exchanger with impinging jets and minichannels technologies for heat recovery from gases – experimental analysis
PublikacjaA dynamic development of technologies allowing waste heat utilization is observed in a correspondence with a pro-ecological approach of the zero waste idea. Such approach becomes the most demanding in the area of low-temperature was heat sources, especially gaseous media. Till now, they were usually not utilized due to unfavorable thermal conditions and high costs. Therefore, the zero waste approach directs research on techniques...
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SiC-based T-type modules for multi-pulse inverter with coupled inductors
PublikacjaThe paper presents SiC-based three-level T-type modules designed for a high-performance 30kVA DC/AC inverter operating at high frequency 85 kHz with low THD of the output voltage. This inverter system consists of two integrated parts. The first part is active and contains three parallelconnected three-phase T-type modules built with fast-switching SiC power transistors. The second, passive part of the system is a set of inductors...
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Influence of metallic porous microlayer on pressure drop and heat transfer of stainless steel plate heat exchanger
PublikacjaThe experimental analysis of passive heat transfer intensification in the case of plate heat exchanger has been carried out. On the heat transfer surface of heat exchanger the metallic porous layer was created. The experiment was accomplished in two stages. In the first stage the commercial stainless steel gasketed plate heat exchanger was investigated, while in the second one – the identical heat exchanger but with the modified...
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Experiment with small objects floating under water in the harbor security aspect.
PublikacjaObservation of the underwater area is the element of general trend which primary purpose is to protect and enhance the safety of the selected region. The aim of the paper is to present the acoustic characteristics of typical objects floating on the surface or under the water, which constitute some knowledge on how to detect these objects. Create a catalog of acoustic signatures and acoustic images of objects mostly floating under...
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HARDWARE AND SOFTWARE OF DIAGNOSTIC SYSTEM OF WHEELED TRACTORS = Hardwer i softwer systemu diagnostycznego ciągników kołowych
PublikacjaPodstawowym elementem systemu diagnostycznego jest komputer pokładowy Fujitsu FUTURO S100 z chłodzeniem pasywnym w wykonaniu odpornym na drgania i wstrząsy, z pamięcią Compact Flesh 16Gb. Do komputera dołączony jest monitor dotykowy NVOX LCD 10" VGA/FVAT. Oprogramowanie komputera obejmujesystem operacyjny Windows XP-2000, driver konwertera USB/DeviceNet oraz opracowany program diagnostyczny. Komputer połączony jest łączem USB z...
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Stress anisotropy characterisation with the help of Barkhausen effect detector with adjustable magnetic field direction
PublikacjaIn the paper we describe a novel apparatus for the measurement of the Barkhausen noise (BN) angular dependence, which in turn may be indicative of the stress induced anisotropy of magnetic properties. Such dependence can be further used for the stress distribution evaluation. The change of magnetization direction in the material is obtained by varying the magnetic flux density in two perpendicular yokes of the apparatus. We present...
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Detailed experimental investigations on frictional pressure drop of R134a during flow boiling in 5 mm diameter channel: The influence of acceleration pressure drop component =Études expérimentales détaillées sur la chute de pression frictionnelle du R134a lors de l'ébullition en écoulement dans un canal de 5 mm de diamètre : influence de la composante d'accélération de la chute de pression
PublikacjaThis article presents detailed two-phase diabatic pressure drop data for refrigerant R134a at a saturation pressure of 5.5 bar corresponding to the saturation temperature of 19.4 °C. Study cases have been set for a mass flux varying from 100 to 500 kg m−2 s−1. The obtained data are used as a validation of the void fraction literature models, a set of graphs shows comparisons, for a representative set of experimental conditions,...
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Lamp of adjustable spectrum for photographic usage
PublikacjaPhotography is a unique rapidly growing interdisciplinary field encompassing aspects of science, art and technology. Expectations of photographers are steadily increasing with the development of technology. One of the areas playing a crucial role in photography is lighting. Consequently, several types of light sources for photographic use have been developed. The ongoing research in this field concentrates on lamps with tunable...
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Determination of dryout localization using a five-equation model of annular flow for boiling in minichannels
PublikacjaDetailed studies have suggested that the critical heat flux in the form of dryout in minichannels occurs when the combined effects of entrainment, deposition, and evaporation of the film make the film flow rate go gradually and smoothly to zero. Most approaches so far used the mass balance equation for the liquid film with appropriate formulations for the rate of deposition and entrainment respectively. It must be acknowledged...
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Hydrogen embrittlement of X2CrNiMoCuN25-6-3 super duplex stainless steel welded joints under cathodic protection
PublikacjaThe effect of cathodic polarization conditions on hydrogen degradation of X2CrNiMoCuN25-6-3 super duplex stainless steel welded joints, obtained using flux cored arc and submerged arc welding methods, was evaluated. Slow strain rate tensile tests of base material and welded specimens, ferrite content measurements, scanning electron microscopy observations, and statistical analysis were performed. It was found that hydrogenation...
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New Tetragonal ReGa5(M) (M = Sn, Pb, Bi) Single Crystals Grown from Delicate Electrons Changing
PublikacjaSingle crystals of the new Ga-rich phases ReGa~5(Sn), ReGa~5(Pb) and ReGa~5(Bi) were successfully obtained from the flux method. The new tetragonal phases crystallize in the space group P4/mnc (No. 128) with vertex-sharing capped Re2@Ga14 oblong chains. Vacancies were discovered on the Ga4 and Ga5 sites, which can be understood as the direct inclusion of elemental Sn, Pb and Bi into the structure. Heat capacity measurements were...
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Models of Brushless Synchronous Generator for Studying Autonomous Electrical Power System
PublikacjaThis is a PhD dissertation. The work presented in this monograph was carried out at the Department of Power Electronics and Electrical Machines, Faculty of Electrical and Control Engineering at the Gdansk University of Technology. Developed during the research models of brushless synchronous generator ware verified using FEM based simulations and measurements conducted on the prototype generator. The main focus of the research...
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A finite element analysis of thermal energy inclination based on ternary hybrid nanoparticles influenced by induced magnetic field
PublikacjaThe use of hybrid nanoparticles to improve thermal processes is a key method that has implications for a variety of interventions utilized in many sectors. This paper aimed to look into the impacts of ternary nanoparticles on hyperbolic tangent materials to establish their thermal characteristics. Flow describing equations have been explored in the presence of heat production, non-Fourier heat flux, and an induced magnetic field....
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Burnout Investigation of Small Diameter Tubes Immersed in Nanofluids
PublikacjaThis paper deals with research into pool boiling critical heat flux (CHF) of water–Al2O3, water–TiO2 and water–Cu nanofluids on horizontal stainless steel tubes. The experiments were conducted under atmospheric pressure. Nanoparticles were tested at concentrations of 0.001%, 0.01%, 0.1% and 1% by weight. Ultrasonic vibration was used in order to stabilize the dispersion of the nanoparticles. Although dispersants were not used to...
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New insights of nanomaterials usage toward superhydrophobic membranes for water desalination via membrane distillation: A review
PublikacjaMembrane distillation (MD) is a promising technology for seawater desalination due to the ability to process high-salinity waters and the ability to be driven by low-grade or waste heat. However, practical applications of MD membranes are limited by the low vapor flux and fouling problem. Recently, there is a growing interest in developing novel MD membrane materials with enhanced hydrophobicity to improve the efficiency of desalination...
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Comparison of heat transfer characteristics in surface cooling using microjets with water, ethanol and HFE7100 as test fluids
PublikacjaAccurate control of cooling parameters is required in ever wider range of technical applications. It is known that reducing the dimensions of the size of nozzle leads to an increase in the economy of cooling and improves its quality. Present study describes research related to the design and construction of the nozzles and microjet study, which may be applied in many technical applications such as in metallurgy, electronics, etc....
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Monitoring and analytics of semivolatile organic compounds (SVOCs) in indoor air
PublikacjaThis paper reviews literature information on the behaviour of semivolatile organic compounds (SVOCs) in the indoor environment, as well as the most likely emission sources. The consecutive stages of analytical procedures used for monitoring SVOCs in indoor environments are described. The most common approaches used for collecting samples from the gas and particulate phases are mentioned. The paper discusses and compares various...
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Influence of metallic porous microlayer on pressure drop and heat transfer of stainless steel plate heat exchanger
PublikacjaThe experimental analysis of passive heat transfer intensification in the case of plate heat exchanger has been carried out. The metallic porous layer was created on the heat transfer surface of analyzed unit. The experiment was accomplished in two stages. In the first stage the commercial stainless steel gasketed plate heat exchanger was investigated, while in the second one – the identical heat exchanger but with the modified...
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Problems and challenges associated with estimating the emissions of organic compounds from indoor materials
PublikacjaFor several years intensive research has been carried out with the aim of developing a database of the types and amounts of pollutants released from indoor materials to the indoor environment. The paper discusses in detail basic problems and challenges encountered when estimating the emissions of chemical compounds released from of indoor materials. Factors affecting the validity of data obtained by using two different types of...
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Influence of Additional Loads on Chosen Gait Parameters and Muscles Activity
PublikacjaThis paper is devoted to human motion analysis and comparison of chosen kinematics parameters during normal gait with and without additional load in a form of backpack. A stability in both cases were compared in both frontal and sagittal planes, by applying a video tracking system. Experimental tests performed on treadmill, passive markers, placed on volunteers bare skin were used. Additionally, an infra-red camera was employed...
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Nonlinear planar modeling of massive taut strings travelled by a force-driven point-mass
PublikacjaThe planar response of horizontal massive taut strings, travelled by a heavy point-mass, either driven by an assigned force, or moving with an assigned law, is studied. A kinematically exact model is derived for the free boundary problem via a variational approach, accounting for the singularity in the slope of the deflected string. Reactive forces exchanged between the point-mass and the string are taken into account via Lagrange...
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A New Microwave Ceramic – Polymer Composite with 0-3 Connectivity
PublikacjaGoal of the present research was to fabricate and study two-phase BiNbO4//PVDF composites with 0-3 connectivity. Such composite consists of there-dimensionally connected polymer matrix loaded with dielectric ceramic particles. In the present case BiNbO4 powder acted as an active phase (dispersed phase) whereas polyvinylidene fluoride (PVDF) acted as a non-active (passive) phase (matrix). BiNbO4//PVDF composites with the volume...
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Pursuing the Deep-Learning-Based Classification of Exposed and Imagined Colors from EEG
PublikacjaEEG-based brain-computer interfaces are systems aiming to integrate disabled people into their environments. Nevertheless, their control could not be intuitive or depend on an active external stimulator to generate the responses for interacting with it. Targeting the second issue, a novel paradigm is explored in this paper, which depends on a passive stimulus by measuring the EEG responses of a subject to the primary colors (red,...
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Acoustic Detector of Road Vehicles Based on Sound Intensity
PublikacjaA method of detecting and counting road vehicles using an acoustic sensor placed by the road is presented. The sensor measures sound intensity in two directions: parallel and perpendicular to the road. The sound intensity analysis performs acoustic event detection. A normalized position of the sound source is tracked and used to determine if the detected event is related to a moving vehicle and to establish the direction of movement....
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CLEANING METHODS FOR DUST DEPOSITED ON THE FRONT COVER OF PHOTOVOLTAIC MODULE
PublikacjaPhotovoltaic modules are one of the renewable energy sources with great potential for application in various regions of the world as well as for different terrain. They are, however, sensitive to external factors, affecting the overall amount of energy generated, such as solar irradiance, shading effects and any form of soil build-up on the front glass cover of solar device. The latter issue happens over a course of weeks, months...
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Selektywne chłodzenie mózgu noworodka po niedotlenieniu okołoporodowym. Cześć 2. Koncepcja hybrydowego systemu selektywnego chłodzenia mózgu noworodka
PublikacjaMózg ludzki jest organem delikatnym, dlatego tak ważne jest zadbanie o to, aby już w momencie przyjścia na świat noworodek miał zapewnioną, w razie konieczności możliwość minimalizacji uszkodzeń neurologicznych, spowodowanych niedotlenieniem okołoporodowym. Niedotlenienie to w dramatyczny sposób zaburza homeostazę mózgu, który jako organ najbardziej energochłonny potrzebuje najwięcej tlenu. Zapoczątkowane brakiem tlenu procesy...
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Thermal and hydraulic phenomena in boundary layer of minijets impingement on curved surfaces
PublikacjaPresented work considers flow and thermal phenomena occurring during the single minijet impingement on curved surfaces, heated with a constant heat flux, as well as the array of minijets. Numerical analyses, based on the mass, momentum and energy conservation laws, were conducted, regarding single phase and two-phase simulations. Focus was placed on the proper model construction, in which turbulence and boundary layer modeling...
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Spatial characterization of H 2: CH 4 dissociation level in microwave ECR plasma source by fibre-optic OES
PublikacjaSpatially resolved optical emission spectroscopy (SR-OES) was used to investigate microwave activated H2/Ar/CH4 plasma under conditions of the electron cyclotron resonance (ECR). The chemistry and composition of the gas phase were studied using self-designed fibre-optic system with echelle type spectrometer during CVD deposition of polycrystalline diamond. One-dimensional intensity profiles of the main species were collected along...
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Thermal performance of a prototype plate heat exchanger with minichannels under boiling conditions
PublikacjaTo solve the problem and to meet the requirements of customers in the field of high heat fluxes transfer in compact units, a new design of plate heat exchanger with minichannels (minichannels PHE) was proposed. The aim was to construct a compact heat exchanger of high effectiveness for the purpose of household cogeneration ORC system. In this paper the experimental analysis of an assembled prototype of such compact heat exchanger...
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Corrosion behavior of hydrogen charged super duplex stainless steel welded joints
PublikacjaThe electrochemical behavior of the weld metal, heat-affected zone (HAZ), and base material of super duplex stainless steel (SDSS) welded joints, made with the application of flux-cored arc welding (FCAW) and submerged arc welding (SAW), were investigated with the use of metallographic examinations (optical microscopy and scanning electron microscopy), potentiodynamic polarization measurements and total hydrogen content determination...
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Numerical Study of Turbulent Flow and Heat Transfer of Nanofluids in Pipes
PublikacjaIn this work, Nusselt number and friction factor are calculated numerically for turbulent pipe flow (Reynolds number between 6000 and 12000) with constant heat flux boundary condition using nanofluids. The nanofluid is modelled with the single-phase approach and the simulation results are compared with experimental data. Ethylene glycol and water, 60:40 EG/W mass ratio, as base fluid and SiO2 nanoparticles are used as nanofluid...
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Single crystal growth and physical properties of MCo2Al9 (M= Sr, Ba)
PublikacjaSingle crystals of SrCo2Al and BaCo2Al9 were grown using a self-flux method. A LeBail analysis of the powder X-ray diffraction patterns show that both compounds crystallize in a hexagonal (P6/mmm) crystal structure with lattice parameters: a = 7.8995(1) Å, c = 3.9159(1) Å for SrCo2Al9, and a = 7.9162(2) Å, c = 3.9702(1) Å for BaCo2Al9 aluminide. The low temperature analysis of the heat capacity measurements give a Sommerfeld...