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Search results for: magnetic field intensity
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Maskowanie obiektu w kształcie elipsoidy w ziemskim polu magnetycznym = Masking ellipsoid-shaped object in the Earth's magnetic field
PublicationW pracy wyznaczono metodą analityczną rozkład okładu prądowego uzwojeń wewnątrz obiektu o powłoce ferromagnetycznej w kształcie wydłużonej elipsoidy, który redukuje zaburzenie rozkładu pola magnetycznego na zewnątrz obiektu.
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Torsional stability capacity of a nano-composite shell based on a nonlocal strain gradient shell model under a three-dimensional magnetic field
PublicationThis paper considers a single-walled composite nano-shell (SWCNS) exposed in a torsional critical stability situation. As the magnetic field affects remarkably nanostructures in the small size, a three-dimensional magnetic field is assessed which contains magnetic effects along the circumferential, radial and axial coordinates system. Based on the results of the nonlocal model of strain gradient small-scale approach and the first-order...
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Magnetic-field-induced electric quadrupole moments for relativistic hydrogenlike atoms: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function
PublicationWe consider a Dirac one-electron atom placed in a weak, static, uniform magnetic field. We show that, to the first order in the strength of the external field, the only electric multipole moments, which are induced by the perturbation in the atom, are those of an even order. Using the Sturmian expansion of the generalized Dirac-Coulomb Green function we derive a closed-form expression for the electric quadrupole moment induced...
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AN OVERVIEW OF HEAT TRANSFER ENHANCEMENT BASED UPON NANOPARTICLES INFLUENCED BY INDUCED MAGNETIC FIELD WITH SLIP CONDITION VIA FINITE ELEMENT STRATEGY
PublicationThe mathematical model of heat generation and dissipation during thermal energy transmission employing nanoparticles in a Newtonian medium is investigated. Dimensionless boundary layer equations with correlations for titanium dioxide, copper oxide, and aluminium oxide are solved by the finite element method. Parameters are varied to analyze their impact on the flow fields. Various numerical experiments are performed consecutively...
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Vibration and buckling characteristics of nonlocal beam placed in a magnetic field embedded in Winkler–Pasternak elastic foundation using a new refined beam theory: an analytical approach
PublicationIn this article, a new refined beam theory, namely one variable first-order shear deformation theory, has been employed to study the vibration and buckling characteristics of nonlocal beam. The beam is exposed to an axial magnetic field and embedded in Winkler–Pasternak foundation. The von Kármán hypothesis along with Hamilton’s principle has been implemented to derive the governing equations for both the vibration and buckling...
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Analiza pola magnetycznego wewnątrz i na zewnątrz cienkościennego obiektu ferromagnetycznego = An analisis of magnetic field inside and outside thin-walled ferromagnetic object
PublicationAnomalia wnoszona przez obiekt ferromagnetyczny znajdujący się w ziemskim polu magnetycznym związana jest z jego namagnesowaniem stałym i indukowanym.W pracy przedstawiono wyniki badań symulacyjnych dotyczące rozkładu indukowanego pola magnetycznego wewnątrz i na zewnątrz obiektu ferromagnetycznego odpowiadającemu kadłubowi okrętu. Analizę numeryczną przeprowadzono w pakiecie OPERA 3d.
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Electric-field-induced magnetic quadrupole moment in the ground state of the relativistic hydrogenlike atom: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function
PublicationStosując rozwinięcie sturmowskie uogólnionej funkcji Greena-Diraca-Coulomba, znaleziono wyrażenie analityczne dla magnetycznego momentu kwadrupolowego, indukowanego przez zewnętrzne słabe, stałe, jednorodne pole elektryczne w stanie podstawowym relatywistycznego atomujednoelektronowego.
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Sound Field Intensity Measurements and Visualization around the Human Head Model . Rozkłąd natężenia pola akustycznego w komorze bezechowej obecności sztucznej głowy i w przypadku braku jej obecności
PublicationThe main goal of this research study was to measure and visualize sound field intensity distribution in and without presence of the human head model. Measurements were performed in the anechoic chamber with the 5 cm grid. Experimental setup consisted of a multitone generator, two loudspeakers, human head model, intensimetric probe, the Cartesian robot applied for precise positioning of the acoustic sensor, and an analyzer. Based...
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Magnetic field-induced electric quadrupole moment in the ground state of the relativistic hydrogen-like atom: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function
PublicationStosując rozwinięcie sturmowskie funkcji Greena-Diraca-Coulomba, znaleziono wyrażenie analityczne dla elektrycznego momentu kwadrupolowego, indukowanego przez zewnętrzne pole magnetyczne w relatywistycznym atomie wodoropodobnym w stanie podstawowym. Wykazano, że jest to efekt czysto relatywistyczny.
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Bio and slide biobearings, their lubrication by non-newtonian fluids and application in non-conventional systems. Vol. 1, Principles of human joint lubrication with non-newtonian liquids for deformable bone and cartilage in magnetic field
PublicationW monografii przedstawiono zasady smarowania stawów człowieka o odkształcalnych chrząstkach i powierzchniach kostnych w polach indukcji magnetycznej. Uwzględnione zostały nienewtonowskie, lepkosprężyste właściwości cieczy synowialnych jako czynnika smarującego. Monografia prezentuje rozkłady wartości ciśnienia i nośności stawów człowieka w warunkach niestacjonarnego smarowania dla drgań o różnych amplitudach i częstotliwościach...
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Multi-functional sensor based on photonic crystal fiber using plasmonic material and magnetic fluid
PublicationA unique highly sensitive photonic crystal fiber is investigated based on plasmonic material and magnetic fluid (MF) for the simultaneous measurement of temperature and magnetic field sensor. The designed sensor is explored by tracing the different parameters such as birefringence, coupling length, power spectrum, and the peak wavelength of the transmission intensity. The magnetic field and temperature computation are attained...
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A fast procedure of stress state evaluation in magnetically anisotropic steels with the help of a probe with adjustable magnetizing field direction
PublicationThe paper presents a novel approach to the stress state evaluation issue. It deals with a strongly (magnetically) anisotropic materials for which a direct interpretation of the Barkhausen effect (BE) intensity would lead to erroneous results. In such a case one has to take into account both the measured BE intensity and the orientation of the magnetisation direction relative to the magnetic easy axis. For the in plane stress distribution...
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HYGRO-MAGNETIC VIBRATION OF THE SINGLE-WALLED CARBON NANOTUBE WITH NONLINEAR TEMPERATURE DISTRIBUTION BASED ON A MODIFIED BEAM THEORY AND NONLOCAL STRAIN GRADIENT MODEL
PublicationIn this study, vibration analysis of single-walled carbon nanotube (SWCNT) has been carried out by using a refined beam theory, namely one variable shear deformation beam theory. This approach has one variable lesser than a contractual shear deformation theory such as first-order shear deformation theory (FSDT) and acts like classical beam approach but with considering shear deformations. The SWCNT has been placed in an axial or...
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Volumetric incorporation of NV diamond emitters in nanostructured F2 glass magneto-optical fiber probes
PublicationIntegration of optically-active diamond particles with glass fibers is a powerful method of scaling diamond's magnetic sensing functionality. We propose a novel approach for the integration of diamond particles containing nitrogen-vacancy centers directly into the fiber core. The core is fabricated by stacking the preform from 790 soft glass canes, drawn from a single rod dip-coated with submicron diamond particles suspended in...
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Smart Approach for Glioma Segmentation in Magnetic Resonance Imaging using Modified Convolutional Network Architecture (U-NET)
PublicationSegmentation of a brain tumor from magnetic resonance multimodal images is a challenging task in the field of medical imaging. The vast diversity in potential target regions, appearance and multifarious intensity threshold levels of various tumor types are few of the major factors that affect segmentation results. An accurate diagnosis and its treatment demand strict delineation of the tumor affected tissues. Herein, we focus on...
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A Planar-Structured Circularly Polarized Single-Layer MIMO Antenna for Wideband Millimetre-Wave Applications
PublicationIn this paper, a simple geometry, planar-structured printed multiple-input-multiple-output (MIMO) antenna utilizing dual circular polarization (CP) is presented. The proposed numerically and experimentally validated design features a fully grounded coplanar waveguide (CPW) and a systematically perturbed feedline radiator. The fringing electric (E) field along the feedline is altered by extruding periodic stubs on each side of the...
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Spatial characterization of H 2: CH 4 dissociation level in microwave ECR plasma source by fibre-optic OES
PublicationSpatially 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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Non-Coaxially Rotating Motion in Casson Martial along with Temperature and Concentration Gradients via First-Order Chemical Reaction
PublicationThe effect of non-coaxial rotation on the transport of mass subjected to first-order chemical reaction is studied analytically. The effects of thermal radiation, buoyancy, constructive and destructive chemical reactions along with Casson fluid in rotating frame are discussed. Time evolution of primary and secondary velocities, energy and solute particles are analyzed. The behavior of flow under the variation of intensity of magnetic...
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ANALIZA ROZKŁADU POLA MAGNETYCZNEGO WEWNĄTRZ OBIEKTU FERROMAGNETYCZNEGO
PublicationW artykule przedstawione zostały wyniki analizy rozkładu natężenia pola magnetycznego wewnątrz obiektu ferromagnetycznego. Obiekt ferromagnetyczny znajdujący się w zewnętrznym polu magnetycznym wywołuje jego zaburzenie, które może być podstawą do wykrycia tego obiektu. Pożądanym zatem jest, aby kompensować to zaburzenie przez zastosowanie cewek kompensujących umieszczonych wewnątrz obiektu. Analiza rozkładu natężenia pola magnetycznego...
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Study on the applicability of the measurements of magnetoelastic properties for a nondestructive evaluation of thermally inducted microstructure changes in the P91 grade steel
PublicationThe paper presents the resuIts of the investigation of the influence of duration and temperature oftempering process on the magnetoacoustic properties of P91 tempered martensite ferritic steeI. Duringtempering of martensitic steels the dislocation density. which initially is very high. systematicallydecreases what is confirmed both by analysis of the width of X-ray diffraction peaks and hardnessmeasurements. Magnetic hysteresis...
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Jednoelektronowy atom Diraca w słabym polu magnetycznym
PublicationW rozprawie przedstawiono opis wpływu zewnętrznego stałego, słabego, jednorodnego pola magnetycznego na jednoelektronowy atom Diraca. Wykorzystując funkcje gęstości ładunku elektrycznego oraz gęstości prądu elektrycznego, rozważono procesy indukowania się w atomie dodatkowych elektromagnetycznych momentów multipolowych. Dokonano analizy indukowanego momentu dipolowego, w wyniku której uzyskano wyrażenie dla magnetyzowalności atomu....
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Study of microstress state of P91 steel using complementary mechanical Barkhausen, magnetoacoustic emission, and X-ray diffraction techniques
PublicationThe paper deals with assessment of microstress state of martensite P91 steel using three complementary techniques: mechanical Barkhausen emission, magnetoacoustic emission (MAE), and X-ray diffraction (XRD) profile analysis. Magnetic coercivity Hc and microstructure were investigated with inductive magnetometry and magnetic force microscopy (MFM), respectively. Internal stress level of P91 steel was modified by heat treatment....
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Metabolomic and antioxidant properties of different varieties and origins of Dragon fruit
PublicationDragon fruit has appealed much concern from consumers as a novelty fruit with potent nutritional and medicinal benefits. Dragon fruit quality warrants comprehensive evaluation, based on the contents of pigments and health- promoting natural compounds in different varieties. This study was aimed to evaluate the differences among dragon fruit varieties extracted with methanol–water (CD3OD-D2O) and methanol (CD3OD) by proton nuclear magnetic...
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Pomiar naprężeń własnych metodą Barkhausena za pomocą sondy z wirującym polem magnetycznym
PublicationW pracy przedstawiono nowy sposób pomiaru naprężeń własnych w elementach konstrukcji z wykorzystaniem polowego efektu Barkhausena. Informację o stanie naprężeń uzyskano z analizy rozkładu kątowego natężenia efektu Barkhausena zmierzonego w sposób automatyczny poprzez sondę z wirującym polem magnetycznym. Przedstawiono zasadę działania i opis układu pomiarowego oraz przykłady wykorzystania tej metody w ocenie stanu naprężenia w...
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Structure and magnetic properties of BeO-Fe2O3-Al2O3-TeO2 glass-ceramic composites
PublicationIn this work, glass-ceramics in the xBeO–20Fe2O3–(80-x)TeO2 system with x = 0–25 mol% were synthesized by the traditional melt quenching route and studied by inductively coupled plasma optical emission spectroscopy, X-ray diffraction, confocal microscopy, infrared and Raman spectroscopy. BeO addition was found to support the crystallization process of Fe2O3 during melting, and an increased BeO content was associated with an increased...
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LOKALIZACJA OBIEKTÓW BUDOWLANYCH W SĄSIEDZTWIE LINII 110 kV
PublicationW artykule omówiono wymagania przepisów w zakresie dopuszczalnych wartości pola elektrycznego i magnetycznego niskiej częstotliwości. Przedstawiono wyniki obliczeń rozkładu pola elektrycznego metodą ładunków stymulowanych i w programie FEMM dla przykładowej lokalizacji obiektu przemysłowego w sąsiedztwie linii 110 kV.
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Analysis of the possibility of creep damage detection in T24 heat resistant steel with the help of magnetic nondestestructive testing methods
PublicationThe paper presents the result of an analysis of applicability of various electromagnetic methods of nondestructive evaluation for creep damage detection in a novel heat resistant steel - T24 grade. Two sample sets, cut out from membrane wall tubes, were investigated – the as-delivered one and another exploited for 36,000 h in a power plant. There are described results of magnetic hysteresis loops B(H), Barkhausen noise (BN) and...
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Mobilny system do detekcji obiektów ferromagnetycznych z magnetometrami pompowanymi optycznie
PublicationW pracy przedstawiono mobilny system do detekcji obiektów ferromagnetycznych. Każdy obiekt ferromagnetyczny zaburza w swoim otoczeniu równomierność pola magnetycznego Ziemi. Zaburzenie to może być zmierzone za pomocą precyzyjnych magnetometrów. W prezentowanym mobilnym systemie zastosowano magnetometry pompowane optycznie pracujące w układzie różnicowym. W pracy opisano magnetometryczny system do detekcji obiektów ferromagnetycznych,...
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On the application of magnetoelastic properties measureme nts for plastic level determination in martensitic steels
PublicationThe change in the dislocation density, induced by plastic deformation, influences strongly the magnetic domain structure inside the material. Being so, classic parameters, like the coercivity or magnetic permeability, can be a good measure of the deformation level, yet their reliable determination in a non-destructive way in industrial environment is problematic. The magnetoacoustic emission (MAE) which results from the non-180...
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Fabrication of high-density nitrogen-vacancy (NV) center-enriched diamond particles through methyl trityl amine (C20H19N) seeding
PublicationDiamond particles (DPs) show promise for advanced applications in bioimaging and quantum sensing due to the presence of defect centers. This work reports a unique growth process for diamond particles composed of nitrogen-vacancy centers (NV-DPs) using a methyl trityl amine (C20H19N) diamondoid seed, which acts as a nitrogen source for NV creation. Growth was performed via microwave plasma-assisted chemical vapor deposition in a...
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POTENCJALNE MOŻLIWOŚCI APLIKACJ TECHNIKI E-NOS W DIAGNOSTYCE MEDYCZNEJ=APPLICATION POTENTIALITIES OF E-NOSE TECHNIQUE IN MEDICAL DIAGNOSTICS
PublicationW pracy przedstawiono i omówiono zasadę działania instrumentu analitycznego - elektronicznego nosa (e-nos) zdolnego rozróżnić i sklasyfikować intensywność zapachu. Urządzenia te służą do automatycznej analizy i rozróżniania próbek zapachowych o złożonym składzie, do rozpoznawania ich charakterystycznych właściwości i najczęściej przeznaczone są do szybkiej analizy jakościowej. Dzięki unikatowym właściwościom technika ta znalazła...
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Magnetic disturbances caused by magnetic contamination of plastics
PublicationIn the study of low magnetic fields precision magnetometers working in a differential system are used. Two optically pumped magnetometers working in a differential system allow for precise measuring of disturbances in the magnetic field. In order to attain high accuracy of magnetic field measurement, it is necessary to use appropriate materials for the construction of a magnetometric system, particularly of those located closely...
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The Dominant Influence of Plastic Deformation Induced Residual Stress on the Barkhausen Effect Signal in Martensitic Steels
PublicationThe paper presents the results of investigation of the influence of plastic deformation on the magnetic properties of martensitic steel (P91 grade). The properties of the hysteresis loops as well as of the Barkhausen effect (BE) signal are analysed for both tensile and compressive loading up to ε = 10% of plastic deformation. The choice of the steel and of the deformation range is unique, since for such combination one can expect...
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Model of ship's magnetic signature
PublicationShips made of ferromagnetic metals interfere with Earth's magnetic field in their surrounding. The disturbance of the magnetic field makes possible localization and even identification of the ship, which could determine a threat to the ship. The measurement of the magnetic field around the ship enables to determine its magnetic signature. The paper presents a multidipoles model of the ship magnetic field, which allows to determine...
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Magnetic signatures of land vehicles
PublicationThe results of numerical simulations of the magnetic field surrounding of land vehicles' models have been presented in this paper. Vehicle containing of ferromagnetic elements distorts the Earth's magnetic field. This distortion can be measured by magnetometers. It is possible to detect and identify an object on the basis of its magnetic signature.
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Insight into (Electro)magnetic Interactions within Facet-Engineered BaFe12O19/TiO2 Magnetic Photocatalysts
PublicationA series of facet-engineered TiO2/BaFe12O19 composites were synthesized through hydrothermal growth of both phases and subsequent deposition of the different, faceted TiO2 nanoparticles onto BaFe12O19 microplates. The well-defined geometry of the composite and uniaxial magnetic anisotropy of the ferrite allowed alternate interfaces between both phases and fixed the orientation between the TiO2 crystal structure and the remanent...
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Sound intensity distribution around organ pipe
PublicationThe aim of the paper was to compare acoustic field around the open and stopped organ pipes. The wooden organ pipe was located in the anechoic chamber and activated with a constant air flow, produced by an external air-compressor. Thus, long-term steady state response was possible to obtain. Multichannel acoustic vector sensor was used to measure the sound intensity distribution of radiated acoustic energy. Measurements have been...
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Numerical modeling of sound intensity distributions around acoustic transducer
PublicationThe aim of this research study is to measure, simulate and compare sound intensity distribution generated by the acoustic transducers of the loudspeaker. The comparison of the gathered data allows for validating the numerical model of the acoustic radiation. An accurate model of a sound source is necessary in mathematical modeling of the sound field distribution near the scattering obstacles. An example of such obstacle is a human...
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MAKING OF FERROMAGNETIC ELLIPTICAL SHELL IN TRANSVERSE MAGNETIC
PublicationA ferromagnetic object, located in the Earth’s magnetic field, changes its distribution. Through measuring such disturbances, one can locate the object and destroy it. To conceal the object, a special winding is placed inside its ferromagnetic shell, and its task is to eliminate the disturbances in the distribution of the Earth’s magnetic field.
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System of wireless magnetic sensors for detection and identification of ferromagnetic vehicles
PublicationThe paper presents the results of deformation of the Earth's magnetic field by land vehicles. Basing on the analysis of the shape of the magnetic field deformation, it is possible to detect and identify a vehicle. In order to eliminate the interference of the Earth's magnetic field by the environment, the measurements were performed in a differential configuration. Under a development project a wireless system of magnetic sensors...
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Detection of ferromagnetic objects in local magnetic anomaly of the Baltic Sea
PublicationIn geological researches several kinds of methods are applied to discovering the natural resources. Planes, helicopters and UAVs (UnmAnned Vehicle) are used in researches in large areas. The gravity, electromagnetic and magnetic methods, which are used in geological researches, are presented in this paper. The special attention was paid to magnetic systems installed on mobile platforms. The magnetic field of the Earth obtained...
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Enhancement of the Magnetic Coupling in Exfoliated CrCl 3 Crystals Observed by Low‐Temperature Magnetic Force Microscopy and X‐ray Magnetic Circular Dichroism
PublicationMagnetic crystals formed by 2D layers interacting by weak van der Waals forces are currently a hot research topic. When these crystals are thinned to nanometric size, they can manifest strikingly different magnetic behavior compared to the bulk form. This can be the result of, for example, quantum electronic confinement effects, the presence of defects, or pinning of the crystallographic structure in metastable phases induced by...
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Magnetic photocatalysts for water treatment
PublicationThe concept of magnetic photocatalysts with separation function requires ferromagnetic material with high magnetic susceptibility to an external magnetic field to enable recycling of composite nanoparticles. Currently, much attention is devoted to functionalization of photocatalyst using MFe2O3, where M =Fe, Zn, Co, Mn. However direct contact between photocatalyst and magnetic iron oxide particles leads to photodissolution of iron...
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Application of magnetic nanoparticles for magnetic solid-phase extraction in preparing biological, environmental and food samples
PublicationThe need to obtain meaningful results as the basis for determining the content of trace amounts of analytes has become the driving force behind the development of modern analytical techniques, including sample-preparation techniques, such as solid-phase extraction (SPE). Recently, great interest was aroused in the use of magnetic nanoparticles (MNPs) in SPE. These materials exhibit high selectivity, and, in small amounts, can provide...
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Magnetic nanocomposites for biomedical applications
PublicationTissue engineering and regenerative medicine have solved numerous problems related to the repair and regeneration of damaged organs and tissues arising from aging, illnesses, and injuries. Nanotechnology has further aided tissue regeneration science and has provided outstanding opportunities to help disease diagnosis as well as treat damaged tissues. Based on the most recent findings, magnetic nanostructures (MNSs), in particular,...
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3D Sound Intensity Measurement Around Organ Pipes Using Acoustic Vector Sensors
PublicationThe aim of the presented paper was to obtain and visualize sound intensity distribution of radiated acoustic energy around the organ pipes. The experimental setup consisted of the multichannel acoustic vector sensor and the specialized Cartesian robot. Measurements were performed in free field with spatial resolution of 0.1 [m]. Two organ pipes, i.e. wooden and metal were measured during the ex-periment. The organ pipes were activated...
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Acoustic Detector of Road Vehicles Based on Sound Intensity
PublicationA 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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Individual Characteristics and Cognitions of Students with Different Levels of Entrepreneurial Intensity
PublicationRESEARCH OBJECTIVE: The objective of the current paper is to verify in what way university students who declare high individual level of entrepreneurial intensity differ from those who are characterized by its intensity level. THE RESEARCH PROBLEM AND METHODS: A statistical analysis of obtained survey results was conducted. The group of research participants included 413 business students. Following statistical methods were used...
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Effect of excitation intensity on slope stability assessed by a simplified approach
PublicationThe paper concerns the selection of a design accelerograms used for the slope stability assessment under earthquake excitation. The aim is to experimentally verify the Arias Intensity as an indicator of the excitation threat to the slope stability. A simple dynamic system consisting of a rigid block on a rigid inclined plane subjected to horizontal excitation is adopted as a slope model. Strong ground motions recorded during earthquakes...
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Mathemathical model of radial passive magnetic bearing
PublicationIn the article mathematical radial model of passive magnetic bearings to ocean engineering units has been presented. The units application in underwater thrusters should increase propulsion systems durability and gives lower maintenance costs. The rotor of electric motor is hanging in magnetic field taken from radial passive magnetic bearings. However axial direction maintenance must be controlled with electromagnets and their...