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Showing 1 to 20 of 70 for “"Curie temperature"”.
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The Diffusion of Carbon in Nickel Above and Below The Curie Temperature
Made available in DSpace on 2014-12-10T17:57:42Z (GMT). No. of bitstreams: 1 6511769.pdf: 1277418 bytes, checksum: 698ebcbe5957f6668b147e5d3743c787 (MD5) Previous issue date: 1965
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Phase transitions in thin iron-palladium films
… Undulating Interference Device) to measure the Curie temperature of thin films of Pd(1-x)Fe(x). The Curie temperatures of these films were found to be significantly less than bulk samples having the same iron concentration. The Curie temperature, furthermore, showed a systematic shift to higher …
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X-ray scattering and lattice dynamics studies for impurity effects on the para-to-ferroelectric phase transformation behavior in lead titanate and barium titanate
Doping of impurities may affect the Curie temperature (T$\sb{\rm c})$ associated with the ferroelectric phase transition in terms of lattice harmonicity and anharmonicity including the creation of the defect energy. Its role in the para-to-ferroelectric transition has been investigated on two …
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Micromagnetic Study of Composite Media for High Density Heat Assisted Magnetic Recording
… GPU parallel computing. Thermal fluctuations and Curie temperature variance are verified to be two import noise sources for FePt recording media besides the grain size distribution and anisotropy variance. A more easily implemented method called thermal switching probability distribution (SPD) is …
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Thermal Modeling of Cooling Time of Submarine Dacite Lapilli Tuff: Brothers Volcano, Kermadec Arc
… a lapilli dacite clast from its initial eruption temperature to the Curie temperature of magnetite to compare to the acquisition of the paleomagnetic remanent vector to test modes of eruption style.</p> <p>The model was created using three initial temperatures: 800℃, 900℃, and 1000°C, and a clast …
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Preparation and characterization of doped lead zirconate titanate Pb(Zr<sub>x</sub>Ti<sub>1-x</sub>)O₃ films
… of various thickness and annealed at a range of temperatures and times. The effects of dopants were studied in terms of the Curie temperature, crystal distortion, transformation temperature, microstructure, optical properties, and electrical properties. In addition to the dopant effect, the …
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Surface magnetic order of ultra thin epitaxial vanadium films on silver
… to bulk vanadium which is paramagnetic at all temperatures. The films of thickness of 5 monolayers possess a surface Curie temperature T$\sb{\rm cs}$ = 475.1 K, and the critical behavior of the magnetization of the films is identical to that predicted by the well-known two-dimensional Ising …
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The possibility of ferromagnetism in the liquid state
<p>The melting temperature and the Curie temperature of a system of spins are calculated in order to study the possibility of ferromagnetism in the liquid state. A model which was proposed by Honda and Kato is used. The calculations are trade in the mean field approximation. Some terms in the …
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Probing the Dynamics of Pressure- and Magnetic Field -Tuned Transitions in Strongly-Correlated Electron Systems: Raman Scattering Studies
… of doping, B isotope, magnetic field, and temperature. Our results reveal a variety of distinct regimes as a function of decreasing T: (i) a paramagnetic semimetal regime, characterized by a collision-dominated electronic scattering response whose scattering rate Gamma decreases with …
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High temperature ultrasonic gas flow sensor based on lead free piezoelectric material
… are identified as the inability to operate at temperatures above 400 °C due to limitation of piezoelectric materials used, and a case for development of an alternative high temperature material is put forward. A novel and highly enhanced, lead free piezoelectric material, suitable for …
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Properties of off stoichiometric yttrium iron garnet
… YIG (~140 Ms~45/emu/cc). Furthermore, the Curie temperature of samples grown on (111) GGG is ~ 310K, in obvious contrast with standard YIG ~560K.
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Actuation of shape memory polymer using magnetic fields for applications in medical devices
… of shape memory polymer using dispersed Curie temperature thermo-regulated particles is proposed. Such a material has potential applications in medical devices which are delivered via catheters. A variety of tests were performed to determine the feasibility of this new approach to shape …
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An Investigation of the Magnetic and Electrical Properties of YNi3
… others, such as the critical exponent at low temperature, differ from previous work. Some of the experiments performed are the first such studies of this material. The key new findings in our high purity samples with residual resistivity ratios (RRR =R300K/R4K) of at least 130, can be …
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Investigating Ferroelastic and Piezoelectric Vibration Damping Behavior in Nickel-Barium Titanate and Nickel-PZT Composites
… analyzer. Tanδ has been found to increase with temperature up to the Curie temperature (Tc) of BaTiO3, after which there was a drop in damping capacity values due to the disappearance of ferroelectric domains above Tc. Furthermore within the frequency range tested, tanδ has been found to …
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The study of weak ferromagnetism by andreev reflection spin spectroscopy and development of bimorph electro-thermal actuators
… such as saturation magnetization or the Curie temperature so that better spintronic materials can be identified and developed. We investigated how the spin polarization of itinerant ferromagnet MnSi changes as it undergoes magnetic phase transition from helical to conical to induced …
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Topological Structures in Ferroic Materials
… phase at moderate fields just below their Curie temperature, which for some compositions was close to room temperature; an essential feature for potential skyrmion-based devices. Results in the literature also provide evidence that the reduced dimensionality of thin plates or films of …
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Understanding Ferroelastic Domain Reorientation as a Damping Mechanism in Ferroelectric Reinforced Metal Matrix Composites
… have been investigated versus frequency, temperature (above and below the Curie temperature of the reinforcement), and number of strain cycles. FR-MMCs currently represent a material system capable of exhibiting increased damping ability, as compared to the structural metal matrix alone. …
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Magnetic and critical behavior of thin terbium(0001)/tungsten(110) films studied by electron capture spectroscopy (ECS)
… the Tb(0001) films is studied as a function of temperature. The topmost layer is found to order ferromagnetically below a surface Curie temperature T$\sb{\rm C\sb s}$ = 249.96 K, which lies above both the bulk Curie and Neel temperatures T$\sb{\rm C\sb b}$ = 220 K and T$\sb{\rm N\sb b}$ = 228 K, …
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Fundamental magnetic properties of Greigite (Fe3S4)
… of the 3d electrons. By measuring the low-temperature Ms of pure greigite samples and based on the Bloch spin wave expansion, the spin wave stiffness of greigite was determined to be ~193 meV·Å2, with a corresponding exchange constant JAB of ~1.03 meV. High-temperature magnetic analyses on …
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Resistivity anomalies for ferromagnetic metals at Curie points
… anomalies of ferromagnetic metals at the Curie point using the itinerant model. The nature of these resistivity anomalies is related to phase transitions of second kind. Current theory describing these anomalies is based on the localized model of the magnetic electrons in ferromagnetic …
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