subject:(Magnetic materials)

Oregon State University

1. Gaskill, Steven G. Equivalent circuit modeling of on-chip magnetic devices based on terminal measurements.

Degree: PhD, Electrical and Computer Engineering, 2014, Oregon State University

URL: http://hdl.handle.net/1957/50151

► The addition of thin-film alloy magnetic materials to integrated circuit processing enables a number of novel monolithic circuits. Examples include fully integrated magnetic field sensors,… (more)

▼ The addition of thin-film alloy magnetic materials to integrated circuit processing enables a number of novel monolithic circuits. Examples include fully integrated magnetic field sensors, signal and power galvanic isolation circuits, and power supplies on chip (PwrSoC). There are several benefits to integrating these traditionally off-chip devices, including improved manufacturability, reduced cost, increased power density, better thermal management, and increase board space efficiency. Accurate circuit models are needed to enable successful circuit simulation of novel on-chip magnetic devices. This thesis focuses on physically-motivated models extracted from terminal characteristics for three categories of devices benefiting from the inclusion of ferromagnetic alloy thin films: a microinductor, a microtransformer, and a microfluxgate. All models are well-behaved asymptotically, are guaranteed passive, and have physical significance to elements and circuit quantities. Measurements used to generate the models are wafer-level compatible and easily obtained with an impedance analyzer or vector network analyzer; no knowledge of the internal physics of the device (e.g. the magnetic material's magnetization behavior) is necessary. For each device an extraction algorithm is presented which obtains all model parameters within a few minutes on a 3.2 GHz Pentium 4 workstation. The resulting models not only match the measurements used to generate the model, but accurately reproduce specific determinative performance figures in their respective applications. Microinductors in buck converters accurately reproduce saturation dynamics with errors less than 2.5% and power efficiency within 0.2% when compared to field solvers. A fabricated microinductor matched the 10 MHz pulse response of the model to within 10%. A microtransformer used as a signal isolation transformer is shown to match the voltage gain to within an error < 0.5%. Additionally, a microtransformer used in an isolated flyback converter captures the current with an error of 3.3% and power efficiency to with 5.6% error when compared to field solvers. The microfluxgate model exhibited accurate performance giving an error of 6.6% when compared to field solvers, and errors less than 7.5% when compared to measurements in the magnetic field sensitivity curve well beyond the linear range. Ultimately, this research enables accurate circuit simulations of novel on-chip magnetic devices potentially realizing first-pass design success. Advisors/Committee Members: Weisshaar, Andreas (advisor), Brekken, Ted (committee member).

Subjects/Keywords: magnetic materials; Magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gaskill, S. G. (2014). Equivalent circuit modeling of on-chip magnetic devices based on terminal measurements. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/50151

Chicago Manual of Style (16^th Edition):

Gaskill, Steven G. “Equivalent circuit modeling of on-chip magnetic devices based on terminal measurements.” 2014. Doctoral Dissertation, Oregon State University. Accessed January 15, 2021. http://hdl.handle.net/1957/50151.

MLA Handbook (7^th Edition):

Gaskill, Steven G. “Equivalent circuit modeling of on-chip magnetic devices based on terminal measurements.” 2014. Web. 15 Jan 2021.

Vancouver:

Gaskill SG. Equivalent circuit modeling of on-chip magnetic devices based on terminal measurements. [Internet] [Doctoral dissertation]. Oregon State University; 2014. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/1957/50151.

Council of Science Editors:

Gaskill SG. Equivalent circuit modeling of on-chip magnetic devices based on terminal measurements. [Doctoral Dissertation]. Oregon State University; 2014. Available from: http://hdl.handle.net/1957/50151

Nanyang Technological University

2. Zhong, Yaoying. Synthesis of Nd-Fe-B based magnetic materials through the mechanochemical process .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/47629

► The limited geographical availability of rare earth elements has resulted in fluctuations in the price of rare earth permanent magnets. The high cost of Nd-Fe-B… (more)

▼ The limited geographical availability of rare earth elements has resulted in fluctuations in the price of rare earth permanent magnets. The high cost of Nd-Fe-B permanent magnets has limited the range of applications of these magnets. Therefore, a reduction in the use of rare earth elements or a reduction in the processing cost of Nd-Fe-B based magnets is urgently needed. However, most conventional processing methods of rare earth magnets are physical methods which require elemental rare earths as precursors, these elements are much more expensive than rare earth oxides. Developing chemical methods using low cost precursors is necessary to reduce the cost of Nd-Fe-B magnets. The large energy product of nanostructured Nd-Fe-B particles is also of interest. In mechanochemical processing, low cost metal oxides (e.g., Nd2O3, Dy2O3, Fe2O3, CoO and B2O3) are reduced by Ca granules during milling, in the presence of a CaO diluent. The desired tetragonal crystal structure of Nd-Fe-B nanoparticles is observed after annealing. It is a low cost and scalable process to produce high coercivity Nd-Fe-B magnetic nanoparticles. However, only a few studies of the mechanochemical synthesis of Nd-Fe-B magnets have been conducted. Detailed studies of the process have not been carried out. Hence in this work, the role of process parameters, reaction mechanisms and reaction kinetics of mechanochemical processing of Nd-Fe-B based magnets were investigated. The effect of process parameters in the mechanochemical process, e.g., milling time and diluent (CaO) content, were investigated during the synthesis of Nd2(Fe,Co)14B magnetic nanoparticles. The diluent content influenced the formation of Nd2(Fe,Co)14B, with the reduction process delayed for larger CaO content. For smaller CaO content, reduction of precursor oxides occurred during milling. For larger CaO content, the reduction reaction could only be triggered by subsequent annealing. With increasing CaO content, the crystallite size of the synthesized Nd2(Fe,Co)14B magnetic nanoparticles increased from 11 nm to 38 nm, accompanied by an enhancement in coercivity. The highest coercivity value of 8.8 kOe was obtained with 50 wt% of diluent. This is the highest coercivity observed for Nd2(Fe,Co)14B magnetic nanoparticles synthesized by chemical methods. To investigate the reaction mechanism during mechanochemical milling, a study of the phase transformations as a function of milling time for a range of milling speeds was performed. It was found that continuous input of mechanical energy was required for the reaction to reach equilibrium. Three stages were observed during mechanochemical milling: (1) fast amorphization of precursor metal oxides, (2) continuous reduction of metal oxides, (3) steady state. A model was proposed to predict the milling kinetics, there is good agreement between experimental data and the predictions. The milling efficiencies at different milling speeds were calculated by the model; the highest milling efficiency was observed at a milling speed of 550 rpm. …

Subjects/Keywords: DRNTU::Engineering::Materials::Magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zhong, Y. (2018). Synthesis of Nd-Fe-B based magnetic materials through the mechanochemical process . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/47629

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhong, Yaoying. “Synthesis of Nd-Fe-B based magnetic materials through the mechanochemical process .” 2018. Thesis, Nanyang Technological University. Accessed January 15, 2021. http://hdl.handle.net/10220/47629.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhong, Yaoying. “Synthesis of Nd-Fe-B based magnetic materials through the mechanochemical process .” 2018. Web. 15 Jan 2021.

Vancouver:

Zhong Y. Synthesis of Nd-Fe-B based magnetic materials through the mechanochemical process . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10220/47629.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhong Y. Synthesis of Nd-Fe-B based magnetic materials through the mechanochemical process . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/47629

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

3. Ahmed, Anansa Sasha Shakil. Multifunctional magnet-polymer transducers .

Degree: 2016, Nanyang Technological University

URL: http://hdl.handle.net/10356/66416

► A key goal of current research is to develop the next generation of materials, structures and systems which can mimic “life” functions, thus imparting extended… (more)

▼ A key goal of current research is to develop the next generation of materials, structures and systems which can mimic “life” functions, thus imparting extended service lifetime and reliability, while also decreasing maintenance and operating costs. Living organisms can sense and react to environmental stimuli, e.g., they can sense damage to their structure and respond appropriately via a healing mechanism. This phenomenon can occur over multiple cycles during its lifetime. The objective of this thesis is to develop a bioinspired artificial material which can mimic the functions of multicycle damage sensing, self healing and actuation. This material will be of great significance in applications such as biomedical coatings or novel aircraft wing “skin” where damage sensing, healing, flexibility, actuation capability and extended lifetimes are required. Magnet filler-polymer matrix composites (Magpol) are an attractive material to combine multiple functions. This is because the inherent properties of both magnetic fillers and the polymer matrix can be readily tuned. Magpol can exhibit quick response, remote contactless actuation, high actuation strain and strain rate, remote heating in alternating magnetic fields (AMF), and self-sensing. These capabilities enable Magpol to respond to a range of stimuli to trigger self healing, sensing and actuation. In this work, a Magnet-polymer composite capable of actuation, damage sensing and self healing was developed by tuning the properties of a magnetic ferrite nanoparticle filler, commercial biocompatible thermoplastic shape memory matrix and stilbene dye molecules. The Curie temperature (Tc) of the Mn-Zn ferrite nanoparticles was tuned to provide a “failsafe” temperature stimulus required for sensing and healing via the application of an AMF; a constant (DC) magnetic field was utilized to induce actuation. Bis(benzoxazolyl)stilbene (BBS) mechanochromic dye was utilized as a colour changing damage sensor, while the shape memory properties of poly (ethylene-co-vinyl acetate) (EVA) was used to extend these functions over multiple cycles, increasing Magpol’s service life. Each of the three functionalities was studied and Magpol’s performance was compared to competing technologies through Ashby charts. The self healing ability of Magpol was evaluated over multiple cycles of damage and repair by subjecting it to multiple types of damage, such as tear tests, wear etc. The first study of the Tc dependence on healing efficiency was conducted and the healing efficiency obtained was comparable to self healing ionomers and supramolecular polymers. The heating behaviour of the magnetic nanoparticles and the healing efficiency was modelled and good agreement was found with experimental results. In a manner similar to biological sensing, colour change was used as a damage sensing mechanism. By studying the BBS interactions in the strained matrix, a linear relationship between the visible colour change and strain/damage was demonstrated in Magpol. The shape recovery property of Magpol was…

Subjects/Keywords: DRNTU::Engineering::Materials::Magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ahmed, A. S. S. (2016). Multifunctional magnet-polymer transducers . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/66416

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ahmed, Anansa Sasha Shakil. “Multifunctional magnet-polymer transducers .” 2016. Thesis, Nanyang Technological University. Accessed January 15, 2021. http://hdl.handle.net/10356/66416.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ahmed, Anansa Sasha Shakil. “Multifunctional magnet-polymer transducers .” 2016. Web. 15 Jan 2021.

Vancouver:

Ahmed ASS. Multifunctional magnet-polymer transducers . [Internet] [Thesis]. Nanyang Technological University; 2016. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10356/66416.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ahmed ASS. Multifunctional magnet-polymer transducers . [Thesis]. Nanyang Technological University; 2016. Available from: http://hdl.handle.net/10356/66416

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

4. Nguyen, Quang Vinh. Magnet-polymer composite transducers .

Degree: 2011, Nanyang Technological University

URL: http://hdl.handle.net/10356/46443

► Current actuation technologies do not provide a satisfactory solution to the requirement of having a muscle like motion, such motion will be very useful in… (more)

Subjects/Keywords: DRNTU::Engineering::Materials::Magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Nguyen, Q. V. (2011). Magnet-polymer composite transducers . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/46443

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Nguyen, Quang Vinh. “Magnet-polymer composite transducers .” 2011. Thesis, Nanyang Technological University. Accessed January 15, 2021. http://hdl.handle.net/10356/46443.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Nguyen, Quang Vinh. “Magnet-polymer composite transducers .” 2011. Web. 15 Jan 2021.

Vancouver:

Nguyen QV. Magnet-polymer composite transducers . [Internet] [Thesis]. Nanyang Technological University; 2011. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10356/46443.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Nguyen QV. Magnet-polymer composite transducers . [Thesis]. Nanyang Technological University; 2011. Available from: http://hdl.handle.net/10356/46443

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

5. Zhao, Xing. Development of zinc oxide-based diluted magnetic semiconductor thin films and nanostructures possessing room temperature ferromagnetism .

Degree: 2013, Nanyang Technological University

URL: http://hdl.handle.net/10356/54657

► Spintronics has emerged as a new technology, which is based on electron spins rather than electron charges to carry information. Spintronics offers an opportunity for… (more)

▼ Spintronics has emerged as a new technology, which is based on electron spins rather than electron charges to carry information. Spintronics offers an opportunity for a new generation of devices combining standard microelectronics with spin-dependent effects that arise from the interactions between the spins of charge carriers and the magnetic properties of materials. In this project, pure ZnO thin films, Cu-doped ZnO thin films, Ni-doped ZnO thin films, pure ZnO nanostructures, and Co-doped ZnO nanostructures were developed as diluted magnetic semiconductor (DMS) materials for potential applications in spintronic devices. Annealing effect under varying conditions on the structural and magnetic properties of the ZnO-based DMS thin films was investigated. A lattice deviation of both as-deposited and annealed pure ZnO thin films was observed through X-ray diffraction (XRD), which was attributed to oxygen vacancies and interstitial Zn in the films. Significant diffusion of O from the bottom to the top surface of the films occurred during annealing in Ar and air as revealed by X-ray photoelectron spectroscopy (XPS), which resulted in increased oxygen vacancies in the films after annealing. Furthermore, prolonged annealing could promote the diffusion of O and induce more oxygen vacancies in the films. Both the as-deposited and the annealed pure ZnO thin films displayed diamagnetism at room temperature, though the oxygen vacancies existed in all the films, indicating that the oxygen vacancies were necessary while only oxygen vacancies were not enough to induce room temperature ferromagnetism (RTFM) of ZnO-based DMS. For the Cu-doped ZnO thin films, significant diffusion of O and Cu from the bottom to the top surface of the films was observed after annealing in Ar or air through XPS. Reduction of Cu occurred in the films annealed in Ar, while oxidization of Cu occurred in the films annealed in air. Extended annealing in air made a higher concentration of oxygen vacancies in the films, and also increased the amount of Cu2+ at Zn2+ sites of ZnO wurtzite lattice. The as-deposited Cu-doped ZnO thin film displayed RTFM that originated from Cu2+ based on the bound magnetic polaron (BMP) model. However, RTFM disappeared in the films annealed in Ar due to the disappearance of Cu2+. Extended annealing of the Cu-doped ZnO films in air enhanced the saturation magnetization (Ms) of the films, which was attributed to a stronger BMP effect. For the Ni-doped ZnO thin films, oxidization of metallic Ni to Ni2+ occurred in the film annealed in air at 600 °C, while reduction of Ni2+ to its metallic state occurred in the film annealed in Ar at 600 and 800 °C. In addition, there appeared to be significant diffusion of Ni from the bottom to the top surface of the film during annealing in Ar at 800 °C. Both as-deposited and annealed Ni-doped ZnO films displayed obvious RTFM which was from metallic Ni, Ni2+ or both with two distinct mechanisms. Furthermore, a significant improvement in Ms in the films was observed after annealing in air or Ar at…

Subjects/Keywords: DRNTU::Engineering::Materials::Magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zhao, X. (2013). Development of zinc oxide-based diluted magnetic semiconductor thin films and nanostructures possessing room temperature ferromagnetism . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/54657

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhao, Xing. “Development of zinc oxide-based diluted magnetic semiconductor thin films and nanostructures possessing room temperature ferromagnetism .” 2013. Thesis, Nanyang Technological University. Accessed January 15, 2021. http://hdl.handle.net/10356/54657.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhao, Xing. “Development of zinc oxide-based diluted magnetic semiconductor thin films and nanostructures possessing room temperature ferromagnetism .” 2013. Web. 15 Jan 2021.

Vancouver:

Zhao X. Development of zinc oxide-based diluted magnetic semiconductor thin films and nanostructures possessing room temperature ferromagnetism . [Internet] [Thesis]. Nanyang Technological University; 2013. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10356/54657.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhao X. Development of zinc oxide-based diluted magnetic semiconductor thin films and nanostructures possessing room temperature ferromagnetism . [Thesis]. Nanyang Technological University; 2013. Available from: http://hdl.handle.net/10356/54657

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Johannesburg

6. Tillwick, Dietlieb Louis. Magnetic properties of uranium monosulphide.

Degree: 2015, University of Johannesburg

URL: http://hdl.handle.net/10210/14890

►

D.Phil. (Physics)

Most of previous magnetic investigations performed on uranium chalcogenides have been limited to polycrystalline specimens. To extend the knowledge on magnetization processes in… (more)

Subjects/Keywords: Magnetism; Magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Tillwick, D. L. (2015). Magnetic properties of uranium monosulphide. (Thesis). University of Johannesburg. Retrieved from http://hdl.handle.net/10210/14890

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Tillwick, Dietlieb Louis. “Magnetic properties of uranium monosulphide.” 2015. Thesis, University of Johannesburg. Accessed January 15, 2021. http://hdl.handle.net/10210/14890.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Tillwick, Dietlieb Louis. “Magnetic properties of uranium monosulphide.” 2015. Web. 15 Jan 2021.

Vancouver:

Tillwick DL. Magnetic properties of uranium monosulphide. [Internet] [Thesis]. University of Johannesburg; 2015. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10210/14890.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Tillwick DL. Magnetic properties of uranium monosulphide. [Thesis]. University of Johannesburg; 2015. Available from: http://hdl.handle.net/10210/14890

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Northeastern University

7. Taheri, Parisa. Design, processing and characterization of mechanically alloyed galfenol & lightly rare-earth doped FeGa alloys as smart materials for actuators and transducers.

Degree: PhD, Department of Electrical and Computer Engineering, 2016, Northeastern University

URL: http://hdl.handle.net/2047/D20239605

► Smart materials find a wide range of application areas due to their varied response to external stimuli. The different areas of application can be in… (more)

Subjects/Keywords: galfenol; magnetic materials; magnetostrictive materials; smart materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Taheri, P. (2016). Design, processing and characterization of mechanically alloyed galfenol & lightly rare-earth doped FeGa alloys as smart materials for actuators and transducers. (Doctoral Dissertation). Northeastern University. Retrieved from http://hdl.handle.net/2047/D20239605

Chicago Manual of Style (16^th Edition):

Taheri, Parisa. “Design, processing and characterization of mechanically alloyed galfenol & lightly rare-earth doped FeGa alloys as smart materials for actuators and transducers.” 2016. Doctoral Dissertation, Northeastern University. Accessed January 15, 2021. http://hdl.handle.net/2047/D20239605.

MLA Handbook (7^th Edition):

Taheri, Parisa. “Design, processing and characterization of mechanically alloyed galfenol & lightly rare-earth doped FeGa alloys as smart materials for actuators and transducers.” 2016. Web. 15 Jan 2021.

Vancouver:

Taheri P. Design, processing and characterization of mechanically alloyed galfenol & lightly rare-earth doped FeGa alloys as smart materials for actuators and transducers. [Internet] [Doctoral dissertation]. Northeastern University; 2016. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/2047/D20239605.

Council of Science Editors:

Taheri P. Design, processing and characterization of mechanically alloyed galfenol & lightly rare-earth doped FeGa alloys as smart materials for actuators and transducers. [Doctoral Dissertation]. Northeastern University; 2016. Available from: http://hdl.handle.net/2047/D20239605

Mississippi State University

8. Guldal, Serkan. FIRST-PRINCIPLES STUDY OF THE SITE OCCUPANCY AND MAGNETIC PROPERTIES OF ZINC-TIN-SUBSTITUTED STRONTIUM HEXAFERRITE.

Degree: MS, Physics and Astronomy, 2011, Mississippi State University

URL: http://sun.library.msstate.edu/ETD-db/theses/available/etd-07072011-131106/ ;

► I performed first principles studies of the site occupancy and magnetic properties of zinc-tin-substituted strontium hexaferrite by using density functional theory. In this study,… (more)

Subjects/Keywords: DFT; strontium hexaferrite; magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Guldal, S. (2011). FIRST-PRINCIPLES STUDY OF THE SITE OCCUPANCY AND MAGNETIC PROPERTIES OF ZINC-TIN-SUBSTITUTED STRONTIUM HEXAFERRITE. (Masters Thesis). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-07072011-131106/ ;

Chicago Manual of Style (16^th Edition):

Guldal, Serkan. “FIRST-PRINCIPLES STUDY OF THE SITE OCCUPANCY AND MAGNETIC PROPERTIES OF ZINC-TIN-SUBSTITUTED STRONTIUM HEXAFERRITE.” 2011. Masters Thesis, Mississippi State University. Accessed January 15, 2021. http://sun.library.msstate.edu/ETD-db/theses/available/etd-07072011-131106/ ;.

MLA Handbook (7^th Edition):

Guldal, Serkan. “FIRST-PRINCIPLES STUDY OF THE SITE OCCUPANCY AND MAGNETIC PROPERTIES OF ZINC-TIN-SUBSTITUTED STRONTIUM HEXAFERRITE.” 2011. Web. 15 Jan 2021.

Vancouver:

Guldal S. FIRST-PRINCIPLES STUDY OF THE SITE OCCUPANCY AND MAGNETIC PROPERTIES OF ZINC-TIN-SUBSTITUTED STRONTIUM HEXAFERRITE. [Internet] [Masters thesis]. Mississippi State University; 2011. [cited 2021 Jan 15]. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-07072011-131106/ ;.

Council of Science Editors:

Guldal S. FIRST-PRINCIPLES STUDY OF THE SITE OCCUPANCY AND MAGNETIC PROPERTIES OF ZINC-TIN-SUBSTITUTED STRONTIUM HEXAFERRITE. [Masters Thesis]. Mississippi State University; 2011. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-07072011-131106/ ;

Penn State University

9. Talalai, Gregory A. Theory of Electromagnetic Waves in Anisotropic, Magneto-Dielectric, Antenna Substrates.

Degree: 2018, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/14971gat131

► The unique electromagnetic properties of magneto-dielectric composite materials, including ferromagnetic particle composites, ferromagnetic film laminates, and crystal-oriented ferrites have yet to be extensively leveraged in… (more)

▼ The unique electromagnetic properties of magneto-dielectric composite materials, including ferromagnetic particle composites, ferromagnetic film laminates, and crystal-oriented ferrites have yet to be extensively leveraged in the design of modern microwave devices and antennas. By surveying the relevant literature, we first compile the relevant information on the dynamic permeability of magneto-dielectric materials, focusing on the various formulations of Snoek’s laws, their achievable permeability spectra, and the sources of anisotropy in a passive material medium. In subsequent chapters, an electromagnetic theory is developed for the investigation of planar antennas printed on anisotropic, magneto-dielectric substrates. For the case of a substrate whose in-plane permittivity and permeability are isotropic, expressions are derived for the surface wave modes. Similar to an isotropic substrate, the anisotropic magneto-dielectric substrate admits of a finite series of surface wave modes, which exist only provided the frequency of operation is above their respective cutoff frequencies. In most cases, the primary TM mode has no cutoff frequency. However, contrary to an isotropic substrate, the primary TM surface wave mode is suppressed completely in the anisotropic substrate provided the in-plane permeability, and out-of-plane permittivity are equal to 1. The more general theory for a fully anisotropic substrate can be developed indirectly through an investigation of wave propagation and radiation along principal axes and planes of the material. TE and TM decompositions of the electromagnetic field may be given for waves propagating within principal planes, but are impossible for arbitrary directions of propagation. An eigenvector approach shows how to resolve the electromagnetic field solutions into types, but these classifications are not, in general, TE/TM. For planar antennas the anisotropic magnetic response of a magneto-dielectric substrate enables circularly polarized radiation, even for single-fed linear antennas. Furthermore, the cutoff frequencies for the surface wave modes become directionally dependent. Dyadic Green’s functions are derived for a grounded, infinite, anisotropic magneto-dielectric substrate using spectral domain techniques. Utilizing the dyadic Green’s functions, the surface wave excitations and radiation patterns of short electric dipole antennas are calculated. The principal plane patterns for a dipole over a substrate possessing in-plane anisotropy are also derived. A method of moments computer program is developed for the numerical investigation of the input impedance and efficiency of microstrip dipoles printed over an anisotropic magneto-dielectric substrate. Example results are given to illustrate the effect of the anisotropic properties of the magneto-dielectric substrate on the dipole’s resonant length, impedance, and efficiency. Notably, the results indicate that a higher efficiency is obtained if the permittivity of the substrate in the direction normal to the air-substrate interface… Advisors/Committee Members: James Kenneth Breakall, Dissertation Advisor/Co-Advisor, James Kenneth Breakall, Committee Chair/Co-Chair, Victor P Pasko, Committee Member, Julio Urbina, Committee Member, Michael T Lanagan, Outside Member.

Subjects/Keywords: Magnetic Materials; Antennas; Electromagnetic Theory

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Talalai, G. A. (2018). Theory of Electromagnetic Waves in Anisotropic, Magneto-Dielectric, Antenna Substrates. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/14971gat131

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Talalai, Gregory A. “Theory of Electromagnetic Waves in Anisotropic, Magneto-Dielectric, Antenna Substrates.” 2018. Thesis, Penn State University. Accessed January 15, 2021. https://submit-etda.libraries.psu.edu/catalog/14971gat131.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Talalai, Gregory A. “Theory of Electromagnetic Waves in Anisotropic, Magneto-Dielectric, Antenna Substrates.” 2018. Web. 15 Jan 2021.

Vancouver:

Talalai GA. Theory of Electromagnetic Waves in Anisotropic, Magneto-Dielectric, Antenna Substrates. [Internet] [Thesis]. Penn State University; 2018. [cited 2021 Jan 15]. Available from: https://submit-etda.libraries.psu.edu/catalog/14971gat131.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Talalai GA. Theory of Electromagnetic Waves in Anisotropic, Magneto-Dielectric, Antenna Substrates. [Thesis]. Penn State University; 2018. Available from: https://submit-etda.libraries.psu.edu/catalog/14971gat131

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Brock University

10. Wang, Jian. The design, synthesis and characterization of new building blocks for the preparation of molecule-based magnetic materials .

Degree: Department of Chemistry, 2007, Brock University

URL: http://hdl.handle.net/10464/1680

► Two new families of building blocks have been prepared and fully characterized and their coordination chemistry exploited for the preparation of molecule-based magnetic materials. The… (more)

▼ Two new families of building blocks have been prepared and fully characterized and their coordination chemistry exploited for the preparation of molecule-based magnetic materials. The first class of compounds were prepared by exploiting the chemistry of 3,3'-diamino-2,2'-bipyridine together with 2-pyridine carbonyl chloride or 2-pyridine aldehyde. Two new ligands, 2,2'-bipyridine-3,3'-[2-pyridinecarboxamide] (Li, 2.3) and N'-6/s(2-pyridylmethyl) [2,2'bipyridine]-3,3'-diimine (L2, 2.7), were prepared and characterized. For ligand L4, two copper(II) coordination compounds were isolated with stoichiometrics [Cu2(Li)(hfac)2] (2.4) and [Cu(Li)Cl2] (2.5). The molecular structures of both complexes were determined by X-ray crystallography. In both complexes the ligand is in the dianionic form and coordinates the divalent Cu(II) ions via one amido and two pyridine nitrogen donor atoms. In (2.4), the coordination geometry around both Cu11 ions is best described as distorted trigonal bipyramidal where the remaining two coordination sites are satisfied by hfac counterions. In (2.5), both Cu(II) ions adopt a (4+1) distorted square pyramidal geometry. One copper forms a longer apical bond to an adjacent carbonyl oxygen atom, whereas the second copper is chelated to a neighboring Cu-Cl chloride ion to afford chloride bridged linear [Cu2(Li)Cl2]2 tetramers that run along the c-axis of the unit cell. The magnetic susceptibility data for (2.4) reveal the occurrence of weak antiferromagnetic interactions between the copper(II) ions. In contrast, variable temperature magnetic susceptibility measurements for (2.5) reveal more complex magnetic properties with the presence of ferromagnetic exchange between the central dimeric pair of copper atoms and weak antiferromagnetic exchange between the outer pairs of copper atoms. The Schiff-base bis-imine ligand (L2, 2.7) was found to be highly reactive; single crystals grown from dry methanol afforded compound (2.14) for which two methanol molecules had added across the imine double bond. The susceptibility of this ligand to nucleophilic attack at its imine functionality assisted via chelation to Lewis acidic metal ions adds an interesting dimension to its coordination chemistry. In this respect, a Co(II) quaterpyridine-type complex was prepared via a one-pot transformation of ligand L2 in the presence of a Lewis acidic metal salt. The rearranged complex was characterized by X-ray crystallography and a reaction mechanism for its formation has been proposed. Three additional rearranged complexes (2.13), (2.17) and (2.19) were also isolated when ligand (L2, 2.7) was reacted with transition metal ions. The molecular structures of all three complexes have been determined by X-ray crystallography. The second class of compounds that are reported in this thesis, are the two diacetyl pyridine derivatives, 4-pyridyl-2,6-diacetylpyridine (5.5) and 2,2'-6,6'-tetraacetyl-4,4'-bipyridine (5.15). Both of these compounds have been designed as intermediates for the metal templated…

Subjects/Keywords: Magnetic materials.

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wang, J. (2007). The design, synthesis and characterization of new building blocks for the preparation of molecule-based magnetic materials . (Thesis). Brock University. Retrieved from http://hdl.handle.net/10464/1680

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wang, Jian. “The design, synthesis and characterization of new building blocks for the preparation of molecule-based magnetic materials .” 2007. Thesis, Brock University. Accessed January 15, 2021. http://hdl.handle.net/10464/1680.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wang, Jian. “The design, synthesis and characterization of new building blocks for the preparation of molecule-based magnetic materials .” 2007. Web. 15 Jan 2021.

Vancouver:

Wang J. The design, synthesis and characterization of new building blocks for the preparation of molecule-based magnetic materials . [Internet] [Thesis]. Brock University; 2007. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10464/1680.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wang J. The design, synthesis and characterization of new building blocks for the preparation of molecule-based magnetic materials . [Thesis]. Brock University; 2007. Available from: http://hdl.handle.net/10464/1680

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Hong Kong

11. 顧若愚. Physical properties of some magnetic systems.

Degree: 2000, University of Hong Kong

URL: http://hdl.handle.net/10722/35945

Subjects/Keywords: Magnetic materials.

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

顧若愚. (2000). Physical properties of some magnetic systems. (Thesis). University of Hong Kong. Retrieved from http://hdl.handle.net/10722/35945

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

顧若愚. “Physical properties of some magnetic systems.” 2000. Thesis, University of Hong Kong. Accessed January 15, 2021. http://hdl.handle.net/10722/35945.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

顧若愚. “Physical properties of some magnetic systems.” 2000. Web. 15 Jan 2021.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Vancouver:

顧若愚. Physical properties of some magnetic systems. [Internet] [Thesis]. University of Hong Kong; 2000. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10722/35945.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

顧若愚. Physical properties of some magnetic systems. [Thesis]. University of Hong Kong; 2000. Available from: http://hdl.handle.net/10722/35945

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Not specified: Masters Thesis or Doctoral Dissertation

University of Waterloo

12. Attia, Hussein. Artificial Magnetic Materials for High Gain Planar Antennas.

Degree: 2011, University of Waterloo

URL: http://hdl.handle.net/10012/5825

► A new method is proposed to enhance the gain and efficiency of planar printed antennas. The proposed method is based on using artificial magnetic materials… (more)

▼ A new method is proposed to enhance the gain and efficiency of planar printed antennas. The proposed method is based on using artificial magnetic materials as a superstrate for planar printed antennas while maintaining the low-profile attractive feature of these antennas. It is found that the antenna's gain increases as the permeability of the superstrate increases. Due to the lack of low-loss natural magnetic materials in the microwave band, designing artificial materials with magnetic properties has become increasingly attractive in recent years. In particular, using magneto-dielectric superstrates reduces the wavelength in the media leading to a miniaturized composite structure (antenna with superstrate). The split ring resonator SRR is used as a unit cell of an artificial magnetic superstrate for a microstrip antenna to enhance the antenna gain and efficiency. Also, in this work, mechanism of operation for artificial magnetic materials is theoretically investigated. Analytical and numerical methods are provided to model the behaviour of these materials. Full-wave analysis of multilayered periodic structures is an expensive computational task which requires considerable computer resources. In this work, a fast analytical solution for the radiation field of a microstrip antenna loaded with a generalized superstrate is proposed. The proposed solution is based on using the cavity model in conjunction with the reciprocity theorem and the transmission line analogy. The proposed analytical formulation reduces the simulation time by two orders of magnitude in comparison with full-wave analysis. The method presented in this work is verified using both numerical and experimental results for the case of a patch antenna covered with an artificial 3D periodic superstrate. Another useful feature of a microstrip antenna covered with superstrate is controlling the direction and beamwidth of the main beam of the antenna. Beam steering has been traditionally implemented in antenna arrays using phase shifters which result in complex and expensive structures and suffer from high loss and mass. This work provides a novel method to steer the main beam of a patch antenna by partially covering it with a high refractive index superstrate. The beam steering of a single patch is possible because of the dual-slot radiation mechanism of the microstrip antenna (according to the cavity model). Full-wave simulations, analytical modeling and experiments are provided to support the proposed technique of beam steering in planar antennas.

Subjects/Keywords: Antenna; Artificial Magnetic Materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Attia, H. (2011). Artificial Magnetic Materials for High Gain Planar Antennas. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/5825

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Attia, Hussein. “Artificial Magnetic Materials for High Gain Planar Antennas.” 2011. Thesis, University of Waterloo. Accessed January 15, 2021. http://hdl.handle.net/10012/5825.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Attia, Hussein. “Artificial Magnetic Materials for High Gain Planar Antennas.” 2011. Web. 15 Jan 2021.

Vancouver:

Attia H. Artificial Magnetic Materials for High Gain Planar Antennas. [Internet] [Thesis]. University of Waterloo; 2011. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10012/5825.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Attia H. Artificial Magnetic Materials for High Gain Planar Antennas. [Thesis]. University of Waterloo; 2011. Available from: http://hdl.handle.net/10012/5825

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Houston

13. Song, Shuangqi 1982-. Electrochemical Synthesis of Magnetic Nanostructures for Mutifunctionalization.

Degree: PhD, Materials Engineering, 2012, University of Houston

URL: http://hdl.handle.net/10657/771

► Compared to the traditional physical vapor deposition or chemical synthesis methods, electrochemical deposition has the advantages of low cost, high yield, low processing temperature and… (more)

▼ Compared to the traditional physical vapor deposition or chemical synthesis methods, electrochemical deposition has the advantages of low cost, high yield, low processing temperature and is easy to scale-up. In this study, we aim to reveal the nanoscale electrochemical growth mechanism and develop efficient electrochemical based approaches to produce multifunctional nanomaterials and structures that are difficult to obtain by other synthesis methods. This study focuses on developing electrochemical based nanomanufacturing techniques to synthesize magnetic nanostructures with controllable size, morphology, composition and structure with cost efficiency and scalability. The dissertation includes two research themes: 1) Electrodeposition mechanism study of metallic nanostructure on carbon micro- nano-structure surfaces; and 2) Electrochemical synthesis of non-spherical magnetic nanostructures for bio-medical applications. By combining synchrotron x-ray diffraction/fluorescence and special electrochemical experimental setup design, we demonstrated real time, non-contact and high resolution composition and structure characterization capabilities for electrochemical processes. As an example, we systematically studied the solution concentration, pH value and deposition potential effects on the Ni nucleation, growth, stability and dissolution on the surfaces of carbon micro- and nano-materials. When acidic electroplating solutions are used, the deposited Ni nuclei are found to have strong size dependent instability and can dissolve chemically. This stability also depends on deposition potential; a passivation layer can form under more negative deposition potential which can prevent chemical dissolution and even electrochemical dissolution. At the micron and below dimensions, the substrate surface curvature also shows significant impact on the deposition rate and efficiency when compared to conventional flat substrates. To explore the unique synthesis capability of electrochemical synthesis and application potential of non-spherical nanomaterials, we have fabricated high aspect ratio Fe nanowires with sizes suitable for bio-medical applications. In situ synchrotron diffraction has again been used to provide real time compositional and crystallographic information during electrodeposition. The composition of nanowires with iron at the core and iron oxide at the surface can also be confirmed by TEM-EDS and XPS study. The biocompatibility of the Fe nanowires has been evaluated by using rat-2 fibroblast cells. In summary, through the study of nanoscale nucleation, growth and micro-structure evolution, this research helps to quantify the nanoscale electrochemical process, establish structure-properties correlation and develop novel magnetic materials applications. Advisors/Committee Members: Sun, Li (advisor), Ardebili, Haleh (committee member), Bao, Jiming (committee member), Masson, Philippe J. (committee member), Song, Gangbing (committee member).

Subjects/Keywords: Electrochemistry; Nanostructures; Magnetic materials; Materials engineering

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Song, S. 1. (2012). Electrochemical Synthesis of Magnetic Nanostructures for Mutifunctionalization. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/771

Chicago Manual of Style (16^th Edition):

Song, Shuangqi 1982-. “Electrochemical Synthesis of Magnetic Nanostructures for Mutifunctionalization.” 2012. Doctoral Dissertation, University of Houston. Accessed January 15, 2021. http://hdl.handle.net/10657/771.

MLA Handbook (7^th Edition):

Song, Shuangqi 1982-. “Electrochemical Synthesis of Magnetic Nanostructures for Mutifunctionalization.” 2012. Web. 15 Jan 2021.

Vancouver:

Song S1. Electrochemical Synthesis of Magnetic Nanostructures for Mutifunctionalization. [Internet] [Doctoral dissertation]. University of Houston; 2012. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10657/771.

Council of Science Editors:

Song S1. Electrochemical Synthesis of Magnetic Nanostructures for Mutifunctionalization. [Doctoral Dissertation]. University of Houston; 2012. Available from: http://hdl.handle.net/10657/771

Hong Kong University of Science and Technology

14. Ma, Rong PHYS. The fabrication of low-loss multifunctional magnetodielectric composites and the study for their structure-properties relationship.

Degree: 2019, Hong Kong University of Science and Technology

URL: http://repository.ust.hk/ir/Record/1783.1-100075 ; https://doi.org/10.14711/thesis-991012730461703412 ; http://repository.ust.hk/ir/bitstream/1783.1-100075/1/th_redirect.html

► The miniaturization and integration of electronic devices demand the development of more excellent materials with multifunction as well as novel structural designs. In this dissertation,… (more)

Subjects/Keywords: Magnetic materials ; Composite materials ; Dielectric devices

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ma, R. P. (2019). The fabrication of low-loss multifunctional magnetodielectric composites and the study for their structure-properties relationship. (Thesis). Hong Kong University of Science and Technology. Retrieved from http://repository.ust.hk/ir/Record/1783.1-100075 ; https://doi.org/10.14711/thesis-991012730461703412 ; http://repository.ust.hk/ir/bitstream/1783.1-100075/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ma, Rong PHYS. “The fabrication of low-loss multifunctional magnetodielectric composites and the study for their structure-properties relationship.” 2019. Thesis, Hong Kong University of Science and Technology. Accessed January 15, 2021. http://repository.ust.hk/ir/Record/1783.1-100075 ; https://doi.org/10.14711/thesis-991012730461703412 ; http://repository.ust.hk/ir/bitstream/1783.1-100075/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ma, Rong PHYS. “The fabrication of low-loss multifunctional magnetodielectric composites and the study for their structure-properties relationship.” 2019. Web. 15 Jan 2021.

Vancouver:

Ma RP. The fabrication of low-loss multifunctional magnetodielectric composites and the study for their structure-properties relationship. [Internet] [Thesis]. Hong Kong University of Science and Technology; 2019. [cited 2021 Jan 15]. Available from: http://repository.ust.hk/ir/Record/1783.1-100075 ; https://doi.org/10.14711/thesis-991012730461703412 ; http://repository.ust.hk/ir/bitstream/1783.1-100075/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ma RP. The fabrication of low-loss multifunctional magnetodielectric composites and the study for their structure-properties relationship. [Thesis]. Hong Kong University of Science and Technology; 2019. Available from: http://repository.ust.hk/ir/Record/1783.1-100075 ; https://doi.org/10.14711/thesis-991012730461703412 ; http://repository.ust.hk/ir/bitstream/1783.1-100075/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

15. Ding, Hui. Electric-field control of magnetism in multiferroic composites .

Degree: 2015, Nanyang Technological University

URL: http://hdl.handle.net/10356/65405

► Multiferroic materials have at least two of the ferroic properties, namely ferroelectricity, ferro (anitferro) magnetism and ferroelasticity.The term usually refers to materials that possess both… (more)

▼ Multiferroic materials have at least two of the ferroic properties, namely ferroelectricity, ferro (anitferro) magnetism and ferroelasticity.The term usually refers to materials that possess both ferroelectric and magnetic orders. An interesting and important consequence of the coexistence of multiple orders is the possible coupling between them, which is named magnetoelectric coupling. It implies that the magnetization could be modulated by an electric field and vice versa. We aim to understand the magnetoelectric coupling phenomenon in multiferroic composite systems in this project. Single-phase multiferroic materials are scarce in nature. However, by combining ferroelectric and ferro (ferri) magnetic materials together, we could design composites with multiferroic properties with much more flexibility. In such a composite, magnetoelectric coupling is achieved through interface-mediated strain effect. There are different ways to combine ferroic phases to form composites. In this project, we focus our effort on the two types of composite systems that would exhibit minimal clamping effect, such as the bulk composites and a magnetic film on a piezoelectric substrate. First, the bulk composites consisting barium titanate (BaTiO3) and cobalt ferrite (CoFe2O4) were synthesized using conventional and spark plasma sintering (SPS) techniques. Dense BaTiO3-CoFe2O4 ceramics were obtained at high temperatures in both cases. SPS has the advantage of producing samples with higher density without any secondary phases. Ferroelectric and magnetic properties of the bulk composites were investigated which showsenhanced properties as density of the composite increased. Unfortunately, due to the high leakage current and the small magnetoelectric coupling effect in bulk ceramics, we were not able to achieve electric-field control of magnetism. Subsequently, we investigated a composite where a magnetic film was deposited on a piezoelectric substrate, which had a well-defined, high-quality interface between the two phases, and was totally free of substrate clamping effect. . Magnetic CoFe2O4 films were deposited on piezoelectric Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) single crystal substrates by pulsed laser deposition. Using an active piezoelectric substrate not only eliminates the clamping effect which is prevalent in the conventional composite film systems on passive substrates, but also facilitates effective strain coupling at the interface. Accurate crystal structure investigation confirms the strain transfer between the PMN-PT substrate and the CoFe2O4 film. When an electric field was applied to the PMN-PT substrate, the magnetic response of the CoFe2O4 film clearly altered as revealed by both their magnetic hysteresis loops and domain structures. The demonstrates magnetoelectric coupling between the substrate and the film, which can be explained using a strain transfer model. Our work has provided experimental evidence for the strain mediated magnetoelectric coupling in this composites where a magnetic CoFe2O4 film is on a ferroelectric…

Subjects/Keywords: DRNTU::Engineering::Materials::Magnetic materials; DRNTU::Engineering::Materials::Nanostructured materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ding, H. (2015). Electric-field control of magnetism in multiferroic composites . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/65405

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ding, Hui. “Electric-field control of magnetism in multiferroic composites .” 2015. Thesis, Nanyang Technological University. Accessed January 15, 2021. http://hdl.handle.net/10356/65405.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ding, Hui. “Electric-field control of magnetism in multiferroic composites .” 2015. Web. 15 Jan 2021.

Vancouver:

Ding H. Electric-field control of magnetism in multiferroic composites . [Internet] [Thesis]. Nanyang Technological University; 2015. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10356/65405.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ding H. Electric-field control of magnetism in multiferroic composites . [Thesis]. Nanyang Technological University; 2015. Available from: http://hdl.handle.net/10356/65405

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Hong Kong University of Science and Technology

16. Yan, Peng. Current-induced magnetization dynamics in magnetic nanostructures.

Degree: 2011, Hong Kong University of Science and Technology

URL: http://repository.ust.hk/ir/Record/1783.1-7369 ; https://doi.org/10.14711/thesis-b1155405 ; http://repository.ust.hk/ir/bitstream/1783.1-7369/1/th_redirect.html

► This thesis deals with the study of current-induced magnetization dynamics for both macrospins and magnetic domain walls, driven by the so-called spin transfer torque effect.… (more)

▼ This thesis deals with the study of current-induced magnetization dynamics for both macrospins and magnetic domain walls, driven by the so-called spin transfer torque effect. It consists of three distinct components: (1) a study of spin transfer torque enhancement in dual spin valves in the ballistic regime, (2) a proposal of domain wall propagation due to the synchronization with circularly polarized microwaves, which can be mapped to uniform spin current driven case, and (3) a derivation of an optimal temporally and spatially varying spin current pattern for fast domain wall propagation along nanowires. The spin transfer torque in all-metal dual spin valves, in which two antiparallelly aligned pinned ferromagnetic layers are on the two sides of a free ferromagnetic layer with two thin normal metal spacers in between, is studied in the ballistic regime. It is argued that, similar to the results in the diffusive regime, the spin transfer torque is dramatically enhanced in comparison to that in a conventional spin valve in the ballistic regime. Within the Slonczewski approach, an analytical expression of the torque on the free magnetic layer is obtained, which may serve as a theoretical model for the micromagnetic simulation of the spin dynamics in dual spin valve. Depending on the orientation of free layer and the degree of electron polarization, the spin transfer torque enhancement could be tens of times. The general cases when transmission and reflection probabilities of free layer are different from zero or one are also numerically calculated. Finding a new control parameter for magnetic domain wall motion is important in general and in particular for the spintronics applications. Here, we show that a circularly polarized magnetic field (CPMF) at gigahertz frequency (microwave) can efficiently drive a domain wall to propagate along a magnetic nanowire. Two motion modes are identified: rigid-domain wall propagation at low frequency and oscillatory propagation at high frequency. Moreover, domain wall motion under a CPMF is equivalent to the domain wall motion under a uniform spin current in the current perpendicular to the plane magnetic configuration proposed recently by Khvalkovskiy et al. [Phys. Rev. Lett. 102, 067206 (2009)], and the CPMF frequency plays the role of the current. How to lower the current needed for a technologically useful domain wall propagation speed is also an important issue in nanomagnetism. Based on the modified Landau-Lifshitz-Gilbert equation with both Slonczewski spin-transfer torque and the field-like torque, we derive an optimal temporally and spatially varying spin current pattern for fast domain wall propagation along nanowires. Under such conditions, the domain wall velocity in biaxial wires can be enhanced as much as tens of times higher than that achieved in experiments so far. Moreover, the fast variation of spin polarization can efficiently help domain wall depinning. Possible experimental realizations are discussed.

Subjects/Keywords: Nanostructured materials – Magnetic properties ; Ferromagnetic materials – Magnetic properties

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Yan, P. (2011). Current-induced magnetization dynamics in magnetic nanostructures. (Thesis). Hong Kong University of Science and Technology. Retrieved from http://repository.ust.hk/ir/Record/1783.1-7369 ; https://doi.org/10.14711/thesis-b1155405 ; http://repository.ust.hk/ir/bitstream/1783.1-7369/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Yan, Peng. “Current-induced magnetization dynamics in magnetic nanostructures.” 2011. Thesis, Hong Kong University of Science and Technology. Accessed January 15, 2021. http://repository.ust.hk/ir/Record/1783.1-7369 ; https://doi.org/10.14711/thesis-b1155405 ; http://repository.ust.hk/ir/bitstream/1783.1-7369/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Yan, Peng. “Current-induced magnetization dynamics in magnetic nanostructures.” 2011. Web. 15 Jan 2021.

Vancouver:

Yan P. Current-induced magnetization dynamics in magnetic nanostructures. [Internet] [Thesis]. Hong Kong University of Science and Technology; 2011. [cited 2021 Jan 15]. Available from: http://repository.ust.hk/ir/Record/1783.1-7369 ; https://doi.org/10.14711/thesis-b1155405 ; http://repository.ust.hk/ir/bitstream/1783.1-7369/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Yan P. Current-induced magnetization dynamics in magnetic nanostructures. [Thesis]. Hong Kong University of Science and Technology; 2011. Available from: http://repository.ust.hk/ir/Record/1783.1-7369 ; https://doi.org/10.14711/thesis-b1155405 ; http://repository.ust.hk/ir/bitstream/1783.1-7369/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

17. Ang, Derrick. Magnetic nanoparticle assisted gene delivery .

Degree: 2012, Nanyang Technological University

URL: http://hdl.handle.net/10356/47726

► Gene delivery is the process of delivering foreign DNA into host cells. Viruses are commonly used because of their very high transfection efficiency. Unfortunately, viral… (more)

Subjects/Keywords: DRNTU::Engineering::Materials::Magnetic materials; DRNTU::Engineering::Materials::Biomaterials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ang, D. (2012). Magnetic nanoparticle assisted gene delivery . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/47726

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ang, Derrick. “Magnetic nanoparticle assisted gene delivery .” 2012. Thesis, Nanyang Technological University. Accessed January 15, 2021. http://hdl.handle.net/10356/47726.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ang, Derrick. “Magnetic nanoparticle assisted gene delivery .” 2012. Web. 15 Jan 2021.

Vancouver:

Ang D. Magnetic nanoparticle assisted gene delivery . [Internet] [Thesis]. Nanyang Technological University; 2012. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10356/47726.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ang D. Magnetic nanoparticle assisted gene delivery . [Thesis]. Nanyang Technological University; 2012. Available from: http://hdl.handle.net/10356/47726

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

18. Pitts, J. Roland. Structural and magnetic studies of Al-base rare earth alloys.

Degree: MS, 1972, Oregon Health Sciences University

URL: doi:10.6083/M4MS3QNP ; http://digitalcommons.ohsu.edu/etd/26

Subjects/Keywords: Alloys; Magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Pitts, J. R. (1972). Structural and magnetic studies of Al-base rare earth alloys. (Thesis). Oregon Health Sciences University. Retrieved from doi:10.6083/M4MS3QNP ; http://digitalcommons.ohsu.edu/etd/26

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Pitts, J Roland. “Structural and magnetic studies of Al-base rare earth alloys.” 1972. Thesis, Oregon Health Sciences University. Accessed January 15, 2021. doi:10.6083/M4MS3QNP ; http://digitalcommons.ohsu.edu/etd/26.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Pitts, J Roland. “Structural and magnetic studies of Al-base rare earth alloys.” 1972. Web. 15 Jan 2021.

Vancouver:

Pitts JR. Structural and magnetic studies of Al-base rare earth alloys. [Internet] [Thesis]. Oregon Health Sciences University; 1972. [cited 2021 Jan 15]. Available from: doi:10.6083/M4MS3QNP ; http://digitalcommons.ohsu.edu/etd/26.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Pitts JR. Structural and magnetic studies of Al-base rare earth alloys. [Thesis]. Oregon Health Sciences University; 1972. Available from: doi:10.6083/M4MS3QNP ; http://digitalcommons.ohsu.edu/etd/26

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Utah

19. Vo, Hoa-Lan. An investigation of 1,4-dicyanotetrazine as a building block in molecule-based magnetic materials.

Degree: MS, Chemistry, 2012, University of Utah

URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/1115/rec/226

► Organic ligands are important components in molecule-based magnets, as they allow for control over the physical and magnetic properties. Spin-carrying radical organic ligands, specifically, have… (more)

Subjects/Keywords: Molecule-based magnetic materials; 1,4-dicyanotetrazine

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Vo, H. (2012). An investigation of 1,4-dicyanotetrazine as a building block in molecule-based magnetic materials. (Masters Thesis). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/1115/rec/226

Chicago Manual of Style (16^th Edition):

Vo, Hoa-Lan. “An investigation of 1,4-dicyanotetrazine as a building block in molecule-based magnetic materials.” 2012. Masters Thesis, University of Utah. Accessed January 15, 2021. http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/1115/rec/226.

MLA Handbook (7^th Edition):

Vo, Hoa-Lan. “An investigation of 1,4-dicyanotetrazine as a building block in molecule-based magnetic materials.” 2012. Web. 15 Jan 2021.

Vancouver:

Vo H. An investigation of 1,4-dicyanotetrazine as a building block in molecule-based magnetic materials. [Internet] [Masters thesis]. University of Utah; 2012. [cited 2021 Jan 15]. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/1115/rec/226.

Council of Science Editors:

Vo H. An investigation of 1,4-dicyanotetrazine as a building block in molecule-based magnetic materials. [Masters Thesis]. University of Utah; 2012. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/1115/rec/226

University of Guelph

20. Michalowicz, Carolyn. 1,2,3,5-Dithiadiazolyl Radical Ligands with Sulfur-Containing Heterocyclic R-groups and their Coordination Complexes.

Degree: Master of Applied Science, Department of Chemistry, 2016, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9620

► This thesis presents the first 1,2,3,5-dithiadiazolyl (DTDA) radicals with a sulfur-containing moiety outside the DTDA ring. Three new DTDA-based ligands were synthesized and characterized along… (more)

Subjects/Keywords: DTDA; thiazyl; radicals; SMM; dysprosium; magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Michalowicz, C. (2016). 1,2,3,5-Dithiadiazolyl Radical Ligands with Sulfur-Containing Heterocyclic R-groups and their Coordination Complexes. (Masters Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9620

Chicago Manual of Style (16^th Edition):

Michalowicz, Carolyn. “1,2,3,5-Dithiadiazolyl Radical Ligands with Sulfur-Containing Heterocyclic R-groups and their Coordination Complexes.” 2016. Masters Thesis, University of Guelph. Accessed January 15, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9620.

MLA Handbook (7^th Edition):

Michalowicz, Carolyn. “1,2,3,5-Dithiadiazolyl Radical Ligands with Sulfur-Containing Heterocyclic R-groups and their Coordination Complexes.” 2016. Web. 15 Jan 2021.

Vancouver:

Michalowicz C. 1,2,3,5-Dithiadiazolyl Radical Ligands with Sulfur-Containing Heterocyclic R-groups and their Coordination Complexes. [Internet] [Masters thesis]. University of Guelph; 2016. [cited 2021 Jan 15]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9620.

Council of Science Editors:

Michalowicz C. 1,2,3,5-Dithiadiazolyl Radical Ligands with Sulfur-Containing Heterocyclic R-groups and their Coordination Complexes. [Masters Thesis]. University of Guelph; 2016. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9620

Hong Kong University of Science and Technology

21. Zheng, Rongkun. Exchange bias in magnetic nanoparticles.

Degree: 2004, Hong Kong University of Science and Technology

URL: http://repository.ust.hk/ir/Record/1783.1-2061 ; https://doi.org/10.14711/thesis-b837449 ; http://repository.ust.hk/ir/bitstream/1783.1-2061/1/th_redirect.html

► Exchange bias and related magnetic properties have been studied on CoO coated Co nanoparticles, γ-Fe2O3 coated Fe nanoparticles, α-Cr2O3 coated CrO2 nanoparticles, and Mn doped… (more)

Subjects/Keywords: Nanoparticles ; Magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zheng, R. (2004). Exchange bias in magnetic nanoparticles. (Thesis). Hong Kong University of Science and Technology. Retrieved from http://repository.ust.hk/ir/Record/1783.1-2061 ; https://doi.org/10.14711/thesis-b837449 ; http://repository.ust.hk/ir/bitstream/1783.1-2061/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zheng, Rongkun. “Exchange bias in magnetic nanoparticles.” 2004. Thesis, Hong Kong University of Science and Technology. Accessed January 15, 2021. http://repository.ust.hk/ir/Record/1783.1-2061 ; https://doi.org/10.14711/thesis-b837449 ; http://repository.ust.hk/ir/bitstream/1783.1-2061/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zheng, Rongkun. “Exchange bias in magnetic nanoparticles.” 2004. Web. 15 Jan 2021.

Vancouver:

Zheng R. Exchange bias in magnetic nanoparticles. [Internet] [Thesis]. Hong Kong University of Science and Technology; 2004. [cited 2021 Jan 15]. Available from: http://repository.ust.hk/ir/Record/1783.1-2061 ; https://doi.org/10.14711/thesis-b837449 ; http://repository.ust.hk/ir/bitstream/1783.1-2061/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zheng R. Exchange bias in magnetic nanoparticles. [Thesis]. Hong Kong University of Science and Technology; 2004. Available from: http://repository.ust.hk/ir/Record/1783.1-2061 ; https://doi.org/10.14711/thesis-b837449 ; http://repository.ust.hk/ir/bitstream/1783.1-2061/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Hong Kong University of Science and Technology

22. Wu, Qiang. Magnetic ordering, spin and electronic configurations of iron thin films on tungsten substrates.

Degree: 2013, Hong Kong University of Science and Technology

URL: http://repository.ust.hk/ir/Record/1783.1-7989 ; https://doi.org/10.14711/thesis-b1240149 ; http://repository.ust.hk/ir/bitstream/1783.1-7989/1/th_redirect.html

► Thin films of magnetic materials have attracted a great deal of interest due to the possibility of unique and desirable magnetic properties which promote valuable… (more)

▼ Thin films of magnetic materials have attracted a great deal of interest due to the possibility of unique and desirable magnetic properties which promote valuable technological applications, particularly in the data storage industry. The magnetic properties of Fe thin films were known to be complicated on different substrates due to its structure transition from fcc to bcc and also many kinds of anisotropy competitions. Fe film growth on W(111) surface was carried out to probe the fcc structure according to earlier report. However, our structure investigations by low energy electron microscopy (LEEM) and diffraction (LEED) show no evidence of the formation of fcc Fe over the entire thickness range studied, up to 18 monolayers (ML). Observations are instead consistent with the formation of a well-ordered, laterally (tensile) strained bcc Fe layer that gradually relaxes vertically and develops increasing disorder with increasing thickness. Magnetic measurements of the Fe film on W(111) using spin polarized low energy electron microscopy (SPLEEM) show ferromagnetic order appears at 6 ML, but surprisingly vanishes at 8 ML and reappears just as suddenly at 9 ML during Fe deposition at room temperature. The evolution of magnetism and exchange asymmetry with increasing thickness and the appearance of the ferromagnetic gap are attributed to structural and morphological changes in the strained Fe layer, which eventually lead to a relaxed although highly disordered bcc Fe layer. The magnetization direction of a mono-domainstructure remains constant before and after the magnetization “gap” at 8-9 ML until the formation of a multi-domain structure at about 12 ML. Ferromagnetism between 6-8 ML also vanishes at only five degrees above room temperature. Spin-resolved quantum size effect (QSE) in electron reflectivity from Fe films grown on 1ML and 2ML Cu layer pre-covered W(110) surface is studied with SPLEEM. The analysis of the intensity oscillations using the phase accumulation model provides information on the unoccupied spin polarized band structure in the Fe film above the vacuum level. Compared to Fe / W(110) films, the presence of one non-magnetic Cu layer shifts spin polarized quantum well resonances in the Fe layer uniformly downward in energy by 1.1 eV. The QSE induced intensity oscillations from Fe films on Cu (2ML) / W(110) are obviously weaker than that from Fe films on Cu (1ML) / W(110), and this is attributed to the film roughness caused by the interdiffusion when the Fe is deposited on the fcc Cu(111) surface of Cu (2ML) / W(110). In-plane spin reorientation transition (SRT) is observed at the early stage of Fe growth on Au (2ML) / W(110) substrate, and this indicates the thickness related non-collinear magnetization of Fe thin film. The SRT phenomenon results from that the interaction between the Fe film and the W(110) substrate forces the magnetization of Fe film along [11̄0] direction, with Fe film thickness increasing the magnetization of Fe film would prefer to along the easy axis of bcc Fe, which is [001] .…

Subjects/Keywords: Thin films ; Magnetic properties ; Ferromagnetic materials ; Tungsten

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wu, Q. (2013). Magnetic ordering, spin and electronic configurations of iron thin films on tungsten substrates. (Thesis). Hong Kong University of Science and Technology. Retrieved from http://repository.ust.hk/ir/Record/1783.1-7989 ; https://doi.org/10.14711/thesis-b1240149 ; http://repository.ust.hk/ir/bitstream/1783.1-7989/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wu, Qiang. “Magnetic ordering, spin and electronic configurations of iron thin films on tungsten substrates.” 2013. Thesis, Hong Kong University of Science and Technology. Accessed January 15, 2021. http://repository.ust.hk/ir/Record/1783.1-7989 ; https://doi.org/10.14711/thesis-b1240149 ; http://repository.ust.hk/ir/bitstream/1783.1-7989/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wu, Qiang. “Magnetic ordering, spin and electronic configurations of iron thin films on tungsten substrates.” 2013. Web. 15 Jan 2021.

Vancouver:

Wu Q. Magnetic ordering, spin and electronic configurations of iron thin films on tungsten substrates. [Internet] [Thesis]. Hong Kong University of Science and Technology; 2013. [cited 2021 Jan 15]. Available from: http://repository.ust.hk/ir/Record/1783.1-7989 ; https://doi.org/10.14711/thesis-b1240149 ; http://repository.ust.hk/ir/bitstream/1783.1-7989/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wu Q. Magnetic ordering, spin and electronic configurations of iron thin films on tungsten substrates. [Thesis]. Hong Kong University of Science and Technology; 2013. Available from: http://repository.ust.hk/ir/Record/1783.1-7989 ; https://doi.org/10.14711/thesis-b1240149 ; http://repository.ust.hk/ir/bitstream/1783.1-7989/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Michigan State University

23. Cowen, Jerry Arnold, 1924-. The temperature dependence of the ferromagnetic resonance line width in single crystals of iron and nickel.

Degree: PhD, 1954, Michigan State University

URL: http://etd.lib.msu.edu/islandora/object/etd:27578

Subjects/Keywords: Magnetism; Magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Cowen, Jerry Arnold, 1. (1954). The temperature dependence of the ferromagnetic resonance line width in single crystals of iron and nickel. (Doctoral Dissertation). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:27578

Chicago Manual of Style (16^th Edition):

Cowen, Jerry Arnold, 1924-. “The temperature dependence of the ferromagnetic resonance line width in single crystals of iron and nickel.” 1954. Doctoral Dissertation, Michigan State University. Accessed January 15, 2021. http://etd.lib.msu.edu/islandora/object/etd:27578.

MLA Handbook (7^th Edition):

Cowen, Jerry Arnold, 1924-. “The temperature dependence of the ferromagnetic resonance line width in single crystals of iron and nickel.” 1954. Web. 15 Jan 2021.

Vancouver:

Cowen, Jerry Arnold 1. The temperature dependence of the ferromagnetic resonance line width in single crystals of iron and nickel. [Internet] [Doctoral dissertation]. Michigan State University; 1954. [cited 2021 Jan 15]. Available from: http://etd.lib.msu.edu/islandora/object/etd:27578.

Council of Science Editors:

Cowen, Jerry Arnold 1. The temperature dependence of the ferromagnetic resonance line width in single crystals of iron and nickel. [Doctoral Dissertation]. Michigan State University; 1954. Available from: http://etd.lib.msu.edu/islandora/object/etd:27578

Montana State University

24. Trudnowski, Jacob Donald. Nuclear magnetic resonance studies of wormlike micelles in porous media.

Degree: MS, College of Engineering, 2016, Montana State University

URL: https://scholarworks.montana.edu/xmlui/handle/1/9587

► Interest of worm-like micelles (WLM) in porous media has grown in oil industries as a rock fracturing fluid due to its fluid rheology properties. Non-invasive… (more)

Subjects/Keywords: Nuclear magnetic resonance.; Micelles.; Porous materials.

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Trudnowski, J. D. (2016). Nuclear magnetic resonance studies of wormlike micelles in porous media. (Masters Thesis). Montana State University. Retrieved from https://scholarworks.montana.edu/xmlui/handle/1/9587

Chicago Manual of Style (16^th Edition):

Trudnowski, Jacob Donald. “Nuclear magnetic resonance studies of wormlike micelles in porous media.” 2016. Masters Thesis, Montana State University. Accessed January 15, 2021. https://scholarworks.montana.edu/xmlui/handle/1/9587.

MLA Handbook (7^th Edition):

Trudnowski, Jacob Donald. “Nuclear magnetic resonance studies of wormlike micelles in porous media.” 2016. Web. 15 Jan 2021.

Vancouver:

Trudnowski JD. Nuclear magnetic resonance studies of wormlike micelles in porous media. [Internet] [Masters thesis]. Montana State University; 2016. [cited 2021 Jan 15]. Available from: https://scholarworks.montana.edu/xmlui/handle/1/9587.

Council of Science Editors:

Trudnowski JD. Nuclear magnetic resonance studies of wormlike micelles in porous media. [Masters Thesis]. Montana State University; 2016. Available from: https://scholarworks.montana.edu/xmlui/handle/1/9587

Montana State University

25. Rassi, Erik Michael. Supercritical fluids, oscillatory flow, and partially saturated porous media by magnetic resonance microscopy.

Degree: PhD, College of Engineering, 2011, Montana State University

URL: https://scholarworks.montana.edu/xmlui/handle/1/2106

► The research presented in this dissertation used Magnetic Resonance (MR) techniques to study fluid dynamics in complex systems. The systems investigated were critical and supercritical… (more)

▼ The research presented in this dissertation used Magnetic Resonance (MR) techniques to study fluid dynamics in complex systems. The systems investigated were critical and supercritical fluids, partially saturated porous media, and oscillatory flow. Supercritical fluids (SCF) are useful solvents in green chemistry and oil recovery and are of great current interest in the context of carbon sequestration. Flow in partially saturated porous media and the resultant hydrodynamics are important in fields including but not limited to hydrology, chemical, medical, and the petroleum industry. Lastly, Pulsatile and oscillatory flows are prevalent in many biological, industrial, and natural systems. Displacement propagators were measured at various displacement observation times to quantify the time evolution of dynamics in critical and supercritical fluid flow. In capillary flow, the critical phase transition fluid C2F6 showed increased compressibility compared to the near critical gas and supercritical fluid. These flows exhibit large variations in buoyancy arising from large changes in density due to very small changes in temperature. Ensemble averaged MR measurements were taken to observe the effects on a bead pack partially saturated with air under flowing conditions of water. Air was injected into the bead pack as water flowed simultaneously through the sample. The initial partially saturated state was characterized with MR imaging density maps, free induction decay (FID) experiments, propagators, and velocity maps before the water flow rate was increased. After the maximum flow rate, the MR imaging density maps, FID experiments, propagators, and velocity maps were repeated and compared to the data taken before the maximum flow rate. The work performed here showed that a partially saturated single phase flow had global flow dynamics that returned to characteristic flow statistics once a steady state high flow rate was reached. A system was constructed to provide a controllable and predictable oscillatory flow in order to gain a better understanding of the impact of oscillatory flow on Newtonian and non-Newtonian fluids, specifically water, xanthan gum (XG), polyacrylamide (PAM) colloidal suspensions. The oscillatory flow system coupled with MR measured the velocity distributions and dynamics of the fluid undergoing oscillatory flow at specific points in the oscillation cycle. Advisors/Committee Members: Chairperson, Graduate Committee: Sarah L. Codd, Joseph D. Seymour (co-chair) (advisor).

Subjects/Keywords: Supercritical fluids.; Porous materials.; Magnetic resonance microscopy.

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rassi, E. M. (2011). Supercritical fluids, oscillatory flow, and partially saturated porous media by magnetic resonance microscopy. (Doctoral Dissertation). Montana State University. Retrieved from https://scholarworks.montana.edu/xmlui/handle/1/2106

Chicago Manual of Style (16^th Edition):

Rassi, Erik Michael. “Supercritical fluids, oscillatory flow, and partially saturated porous media by magnetic resonance microscopy.” 2011. Doctoral Dissertation, Montana State University. Accessed January 15, 2021. https://scholarworks.montana.edu/xmlui/handle/1/2106.

MLA Handbook (7^th Edition):

Rassi, Erik Michael. “Supercritical fluids, oscillatory flow, and partially saturated porous media by magnetic resonance microscopy.” 2011. Web. 15 Jan 2021.

Vancouver:

Rassi EM. Supercritical fluids, oscillatory flow, and partially saturated porous media by magnetic resonance microscopy. [Internet] [Doctoral dissertation]. Montana State University; 2011. [cited 2021 Jan 15]. Available from: https://scholarworks.montana.edu/xmlui/handle/1/2106.

Council of Science Editors:

Rassi EM. Supercritical fluids, oscillatory flow, and partially saturated porous media by magnetic resonance microscopy. [Doctoral Dissertation]. Montana State University; 2011. Available from: https://scholarworks.montana.edu/xmlui/handle/1/2106

University of Arizona

26. Mehrten, John Alan, 1932-. Ferrite frequency doubling from 9 to 18 kmc .

Degree: 1961, University of Arizona

URL: http://hdl.handle.net/10150/319407

Subjects/Keywords: Ferrites (Magnetic materials)

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Mehrten, John Alan, 1. (1961). Ferrite frequency doubling from 9 to 18 kmc . (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/319407

Chicago Manual of Style (16^th Edition):

Mehrten, John Alan, 1932-. “Ferrite frequency doubling from 9 to 18 kmc .” 1961. Masters Thesis, University of Arizona. Accessed January 15, 2021. http://hdl.handle.net/10150/319407.

MLA Handbook (7^th Edition):

Mehrten, John Alan, 1932-. “Ferrite frequency doubling from 9 to 18 kmc .” 1961. Web. 15 Jan 2021.

Vancouver:

Mehrten, John Alan 1. Ferrite frequency doubling from 9 to 18 kmc . [Internet] [Masters thesis]. University of Arizona; 1961. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10150/319407.

Council of Science Editors:

Mehrten, John Alan 1. Ferrite frequency doubling from 9 to 18 kmc . [Masters Thesis]. University of Arizona; 1961. Available from: http://hdl.handle.net/10150/319407

University of Arizona

27. Landry, Clifford John, 1930-. Line width behavior of hybrid single crystal garnet ferrites .

Degree: 1962, University of Arizona

URL: http://hdl.handle.net/10150/319420

Subjects/Keywords: Ferrites (Magnetic materials)

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Landry, Clifford John, 1. (1962). Line width behavior of hybrid single crystal garnet ferrites . (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/319420

Chicago Manual of Style (16^th Edition):

Landry, Clifford John, 1930-. “Line width behavior of hybrid single crystal garnet ferrites .” 1962. Masters Thesis, University of Arizona. Accessed January 15, 2021. http://hdl.handle.net/10150/319420.

MLA Handbook (7^th Edition):

Landry, Clifford John, 1930-. “Line width behavior of hybrid single crystal garnet ferrites .” 1962. Web. 15 Jan 2021.

Vancouver:

Landry, Clifford John 1. Line width behavior of hybrid single crystal garnet ferrites . [Internet] [Masters thesis]. University of Arizona; 1962. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10150/319420.

Council of Science Editors:

Landry, Clifford John 1. Line width behavior of hybrid single crystal garnet ferrites . [Masters Thesis]. University of Arizona; 1962. Available from: http://hdl.handle.net/10150/319420

University of Arizona

28. McGregor, Thomas, 1931-. Line width behavior of a single crystal garnet ferrite .

Degree: 1962, University of Arizona

URL: http://hdl.handle.net/10150/347451

Subjects/Keywords: Ferrites (Magnetic materials)

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

McGregor, Thomas, 1. (1962). Line width behavior of a single crystal garnet ferrite . (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/347451

Chicago Manual of Style (16^th Edition):

McGregor, Thomas, 1931-. “Line width behavior of a single crystal garnet ferrite .” 1962. Masters Thesis, University of Arizona. Accessed January 15, 2021. http://hdl.handle.net/10150/347451.

MLA Handbook (7^th Edition):

McGregor, Thomas, 1931-. “Line width behavior of a single crystal garnet ferrite .” 1962. Web. 15 Jan 2021.

Vancouver:

McGregor, Thomas 1. Line width behavior of a single crystal garnet ferrite . [Internet] [Masters thesis]. University of Arizona; 1962. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10150/347451.

Council of Science Editors:

McGregor, Thomas 1. Line width behavior of a single crystal garnet ferrite . [Masters Thesis]. University of Arizona; 1962. Available from: http://hdl.handle.net/10150/347451

Georgia Tech

29. Rondinone, Adam Justin. Superparamagnetic relaxation dynamics of magnetic spinel ferrite nanoparticles.

Degree: PhD, Chemistry, 2001, Georgia Tech

URL: http://hdl.handle.net/1853/30958

Subjects/Keywords: Magnetic materials; Nanoparticles

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rondinone, A. J. (2001). Superparamagnetic relaxation dynamics of magnetic spinel ferrite nanoparticles. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/30958

Chicago Manual of Style (16^th Edition):

Rondinone, Adam Justin. “Superparamagnetic relaxation dynamics of magnetic spinel ferrite nanoparticles.” 2001. Doctoral Dissertation, Georgia Tech. Accessed January 15, 2021. http://hdl.handle.net/1853/30958.

MLA Handbook (7^th Edition):

Rondinone, Adam Justin. “Superparamagnetic relaxation dynamics of magnetic spinel ferrite nanoparticles.” 2001. Web. 15 Jan 2021.

Vancouver:

Rondinone AJ. Superparamagnetic relaxation dynamics of magnetic spinel ferrite nanoparticles. [Internet] [Doctoral dissertation]. Georgia Tech; 2001. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/1853/30958.

Council of Science Editors:

Rondinone AJ. Superparamagnetic relaxation dynamics of magnetic spinel ferrite nanoparticles. [Doctoral Dissertation]. Georgia Tech; 2001. Available from: http://hdl.handle.net/1853/30958

University of British Columbia

30. Banville, Marcel. Sur la theorie de l'aimantation spontanee d'une substance ferromagnetique aux basses temperatures.

Degree: MS- MSc, Physics, 1959, University of British Columbia

URL: http://hdl.handle.net/2429/40266

► In 1930, Bloch derived a formula for the temperature-dependence of the spontaneous magnetisation of a ferromagnetic substance (in the sense of the well-known Heisenberg model)… (more)

▼ In 1930, Bloch derived a formula for the temperature-dependence of the spontaneous magnetisation of a ferromagnetic substance (in the sense of the well-known Heisenberg model) valid asymptotically as the temperature T tends to zero. In 1936, Kramers rederived Bloch's formula using an entirely new approximate method. In 1937, Opechowski applied Kramers’ method to obtain, in addition to Bloch's T³′²-term in the expression for the magnetisation, two additional terms, in T² and T⁵′². In 1956, Dyson found a rigourous method for dealing with this problem. His result shows that there is no T²-term and the T⁵′²-term has a coefficient different from that found by Opechowski. In this thesis, some possibilities are investigated of modifying Kramers' method. In particular, the question is considered, which assumptions in Kramers' method are responsible for the above mentioned discrepancies. In Kramers' method, the partition function of the Heisenberg model is identified with the largest term in its power series expansion. The calculation of the largest term is in turn reduced to a certain random walk problem. This reduction of the problem to a random walk problem involves certain assumptions which we have not tried to modify in this thesis. What is new is a careful discussion of, and improvement on the solution of the random walk problem. The improved method of solving this problem leads to a cubic equation in P¹′², where P is a certain parameter with no single physical meaning. In chapters 6 and 7, a first approximation is obtained by omitting the term in P³′². The resulting quadratic equation in P¹′² leads to an expression for the spontaneous magnetisation containing no term in T² as in Dyson's formula. The solution of the complete cubic equation unfortunately leads to an expression for the spontaneous magnetisation, in which the term in T² reappears again. One obtains again Opechowski's result, except for a small modification of the coefficient of the T⁵′²-term; this is due to a better approximation for the factorials occuring in the calculations. This fact shows that Kramers’ random walk problem constitutes too crude an approximation of the actual problem. After the writing of this thesis was completed, Professor Opechowski found a way of modifying Kramers' method. The calculation of the partition function in the modified method is reduced to a slightly different random walk problem. The expression for the spontaneous magnetisation becomes then identical with Dyson's up to the T⁷′²-term inclusive.

Subjects/Keywords: Magnetism; Magnetic materials

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Banville, M. (1959). Sur la theorie de l'aimantation spontanee d'une substance ferromagnetique aux basses temperatures. (Masters Thesis). University of British Columbia. Retrieved from http://hdl.handle.net/2429/40266

Chicago Manual of Style (16^th Edition):

Banville, Marcel. “Sur la theorie de l'aimantation spontanee d'une substance ferromagnetique aux basses temperatures.” 1959. Masters Thesis, University of British Columbia. Accessed January 15, 2021. http://hdl.handle.net/2429/40266.

MLA Handbook (7^th Edition):

Banville, Marcel. “Sur la theorie de l'aimantation spontanee d'une substance ferromagnetique aux basses temperatures.” 1959. Web. 15 Jan 2021.

Vancouver:

Banville M. Sur la theorie de l'aimantation spontanee d'une substance ferromagnetique aux basses temperatures. [Internet] [Masters thesis]. University of British Columbia; 1959. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/2429/40266.

Council of Science Editors:

Banville M. Sur la theorie de l'aimantation spontanee d'une substance ferromagnetique aux basses temperatures. [Masters Thesis]. University of British Columbia; 1959. Available from: http://hdl.handle.net/2429/40266

		in
And / Or
		in
And / Or
		in
And / Or
		in

Open Access Theses and Dissertations