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Showing 1 to 20 of 40 for “"ferrites"”.
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Cerenkov Radiation From Anisotropic Ferrites
Made available in DSpace on 2014-12-04T21:03:40Z (GMT). No. of bitstreams: 1 6402954.pdf: 3471886 bytes, checksum: bb87b06bd69bcdd6358b68f351db30cd (MD5) Previous issue date: 1963
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Nanocrystalline Transition Metal Ferrites Synthesis, Characterization and Surface Functionalization
In this thesis, a new synthetic methodology for the high yield synthesis of spineltype transition metal ferrite nanoparticles has been developed. This approach is based on the complexation of the first-row transition metal cations with diethylene glycol (DEG) followed by the hydrolysis of the …
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Hyperfine interactions in ferrites and orthoferrites at high pressure
Submitted by William Weathers (weathrs2@illinois.edu) on 2012-04-22T17:17:54Z No. of bitstreams: 1 1974_halasa.pdf: 3132428 bytes, checksum: 380ab58e42a377ba9f6add8751daa288 (MD5)
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Investigation of the high-frequency effects in Mn-Zn ferrites for EMI filter applications
… determine the high-frequency properties of Mn-Zn ferrites up to 20 MHz. Complex permeability and permittivity, as well as specific power loss, are typically provided as one value by the manufacturer, regardless of the core shape and size. Therefore, various magnetic materials are characterized for …
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Comparative study of rare- earth based ferrites for flammable and volatile organic compound gas sensors
… Gas sensors fabricated from the spinel ferrites were tested towards various organic compound vapours (acetone, methanol, p-xylene, ethylbenzene, toluene, and benzene) and flammable gases (LPG, Methane, Propane, Butane and Ammonia) at an operating temperature of 225 °C. The MgCe0.2Fe1.8O4 …
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Comparative of Flammable and Toxic Gas Sensing behavior for Rare-Earth Elements Substituted Cobalt based Spinel Ferrites
… we present a variety of cobalt-based spinel ferrites doped with 4f electron rare-earth ions to be used as flammable gas sensors. These spinel ferrites were fabricated following a glycol hydrothermal chemical-process. Due to their electronic configuration and charge dynamics, they are very …
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Investigation of the promotional effect of Cu and Ag on iron-based Fischer-Tropsch catalysts using ferrites as model catalysts
… active phase. In this study, copper and silver ferrites which are model iron catalysts composed of Cu or Ag as promoters (CuFe2O4, CuFeO2 and AgFeO2) will be prepared via the co-precipitation method. The model catalysts will then be activated in H2 and CO reaction environment and exposured to …
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Radio frequency miniature passive devices: ferrite antennas and inductors
… wave propagation, and RF signal processing. Ferrites possess both frequency-dependent permeability and permittivity. Thus, miniaturization and electromagnetic scaling of antennas and inductors can be realized with the magnetic and dielectric properties of ferrites. In addition, the unique …
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Chemical Correlation of Magnetic Permeability and Microwave Absorption in Spinel Ferrite Nanoparticles
Spinel ferrites (MFe₂O₄, where M = Mn²⁺, Co²⁺, Zn²⁺, etc.) are magnetic nanomaterials with tunable properties that are valuable for wireless communication, memory storage, and electronics. Their complex permeabilities that are governed by composition, particle size, and spin-orbit interactions play …
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Core loss characterization and design optimization of high-frequency power ferrite devices in power electronics applications
… core loss measurement technique for power ferrites, the modeling and analysis of mechanisms of high-frequency losses, and design methodology for optimization for high-frequency magnetics are presented. The high-frequency losses of ferrite materials are characterized employing a large-signal …
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ΚΑΤΑΛΥΤΙΚΕΣ ΙΔΙΟΤΗΤΕΣ ΧΗΜΙΚΩΝ ΟΞΕΙΔΙΩΝ ΤΟΥ ΣΙΔΗΡΟΥ ΚΑΘΑΡΩΝ ΚΑΙ ΜΙΚΤΩΝ ΣΤΗ ΜΕΤΑΤΡΟΠΗ ΤΟΥ ΜΟΝΟΞΕΙΔΙΟΥ ΤΟΥ ΑΝΘΡΑΚΑ ΤΟΥ ΥΔΡΑΕΡΙΟΥ
PURE MAGNETIDE AND MIXED SPINEL FERRITES CONTAINING IN VARIOUS CONCENTRATIONS CR, CO OR NI AS A PROMOTER WERE PREPARED BY COPRECIPITATION, CALCINATION AND, WHEN NEEDED, REDUCTION X-RAY DIFFRACTION AND MOSSBAUER SPECTROSCOPY CONFIRMED THEFORMATION OF SPINEL FERRITES. THE ACTIVITIES OF THE PREPARED …
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ΜΕΛΕΤΗ ΤΗΣ ΕΠΙΔΡΑΣΗΣ ΤΗΣ ΠΑΡΑΣΚΕΥΑΣΤΙΚΗΣ ΔΙΑΔΙΚΑΣΙΑΣ ΣΤΙΣ ΦΥΣΙΚΟΧΗΜΙΚΕΣ ΙΔΙΟΤΗΤΕΣ ΤΩΝ ΦΕΡΡΙΤΩΝ ΤΩΝ ΣΤΟΙΧΕΙΩΝ ΤΗΣ ΣΕΙΡΑΣ ΤΩΝ ΛΑΝΘΑΝΙΔΩΝ. ...
… ON THE CHEMICAL AND PHYSICAL PROPERTIESOF ERBIUM FERRITES WAS INVESTIGATED. FOR THE PREPARATION OF THE VARIOUS ERBIUMFERRITES A "WET CHEMICAL" TECHNIQUE WAS EMPLOYED AND MIXED HYDRATED OXIDES OF ERBIUM AND IRON WITH VARIOUS (G.AR.ER) (G.AT.FE) RATIOS WERE FIRED AT A DESIGNATED, VARYING EACH TIME, …
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Interfacial Phenomena in Electrical Ceramics and the Design and Fabrication of Semiconducting Ceramics
… coefficient of resistance thermistors; and ferrites have been considered.
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Complex oxides of the system Cu-Ni-Fe-O: synthesis parameters, phase formation and properties
… are the solid solutions CuxNi1-xFe2O4, the ferrites occurring in the phase triangle Cu0.5Ni0.5Fe2O4 -Cu0.9Fe2.1O4 - Cu0.5Fe2.5O4 and some copper-nickel oxide solid solutions. Three synthesis routes have been used, namely (i) the preparation and the thermal decomposition of freeze-dried …
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System and Reactor Design, and Materials Testing, for Efficient Thermochemical Solar Fuel Production in Temperature/Pressure Swing Redox Cycles
… 1300℃) is used to reduce metal oxides like doped ferrites or ceria in a low oxygen environment. The reduced metal oxide is then used to split water at ~ 800℃ and atmospheric pressure. The large temperature and pressure swings severely penalize heat-to-fuel conversion efficiency if measures like …
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Analysis of a composite dielectric-ferrite loaded resonator using the transmission line model with application to a tunable dual mode bandpass filter
… using by using two oppositely biased ferrites. Specifically, a change in the applied magnetic field is used to alter the permeability of the ferrite so as to achieve maximum tuning range. Through electromagnetic (EM) simulations and laboratory experiments, tuning of the filter passband …
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High Frequency Magnetic Core Loss Study
… loss models. Several commercially available MnZn ferrites are characterized and modeled. Other than conventional MnZn ferrite materials, three commercial LTCC ferrite materials are characterized for integrated power supply applications. Based on characterized properties of these LTCCs, a group of …
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A one-step ambient temperature ferrite process for treatment of acid mine drainage waters
… massive volumes of AMD are concerned is to form ferrites at ambient temperatures. A second challenge is to form ferrites at ambient temperature in the presence of calcium, as lime (Ca(OH)2) is the most economical agent available for raising pH, but calcium is known to interfere with magnetite …
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Permeability Spectra of Electrodeposited CoFe Film for Inductor Applications
… inductors is vital. Traditional materials like ferrites are unsuitable due to their low stability frequency. Thin film alloy deposition methods, such as electrodeposition, offer scalability and cost efficiency. This thesis investigates the influence of electrochemical process parameters and …
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ΜΕΛΕΤΗ ΔΟΜΙΚΩΝ ΚΑΙ ΜΑΓΝΗΤΙΚΩΝ ΙΔΙΟΤΗΤΩΝ ΣΕ ΥΛΙΚΑ ΜΟΝΙΜΩΝ ΜΑΓΝΗΤΩΝ: ΟΙ ΥΠΟΚΑΤΕΣΤΗΜΕΝΟΙ ΜΕ ΖΝ ΕΞΑΓΩΝΙΚΟΙ ΦΕΡΙΤΕΣ ΜΝ2-W
… METALS OXIDES, NAMELY THE W-TYPE HEXAGONAL FERRITES CONTAINING ZN AND MN, WITH CHEMICAL FORMULAE SRZNXMN2-XFE16027 AND BAZNXMN2- XFE16O27O. THE STRUCTURAL AND MAGNETIC PROPERTIESOF THESE SERIES ARE STUDIED AND THEIR TECHNOLOGICAL INTEREST AS PERMANENT MAGNET MATERIALS IS EXAMINED. SINGLE …
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