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Articles 181 - 210 of 326
Full-Text Articles in Ceramic Materials
Electrical Properties Of Phosphate Glasses, Andrea Mogus-Milankovic, Ana Santic, Signo Tadeu Dos Reis, D. E. Day
Electrical Properties Of Phosphate Glasses, Andrea Mogus-Milankovic, Ana Santic, Signo Tadeu Dos Reis, D. E. Day
Materials Science and Engineering Faculty Research & Creative Works
Investigation of the electrical properties of phosphate glasses where transition metal oxide such as iron oxide is the network former and network modifier is presented. Phosphate glasses containing iron are electronically conducting glasses where the polaronic conduction is due to the electron hopping from low to high iron valence state. The identification of structural defects caused by ion/polaron migration, the analysis of dipolar states and electrical conductivity in iron phosphate glasses containing various alkali and mixed alkali ions was performed on the basis of the impedance spectroscopy (IS). The changes in electrical conductivity from as-quenched phosphate glass to fully crystallized …
Development Of Microbial And Enzymatic Fuel Cells For Bio-Inspired Power Sources, Fatih Dogan, Shelley Minteer
Development Of Microbial And Enzymatic Fuel Cells For Bio-Inspired Power Sources, Fatih Dogan, Shelley Minteer
Materials Science and Engineering Faculty Research & Creative Works
This report is based on some of the revolutionary concepts described in the Road Map on Bioinspired Power Systems within the AFRLRW Campus Challenge II. Development of biofuel cell concepts integrated with fuel regeneration and energy storage capabilities are proposed to create a compact and self-sustaining power system. The first part of this work identified a sediment based microbial fuel cell that could power small electronics and maintain electrical activity over long periods of time. AFRLRW does not feel that this work adequately addresses the original scope nor does it provide a basis on which to continue work. The second …
Yttria Stabilized Zirconia As A Candidate For High Energy Density Capacitor, Oratai Jongprateep, Vladimir Petrovsky, Fatih Dogan
Yttria Stabilized Zirconia As A Candidate For High Energy Density Capacitor, Oratai Jongprateep, Vladimir Petrovsky, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
As one of the main components in power converters, dielectric capacitors can play crucial roles in facilitating power conversion in various applications, such as hybrid-electric and fuel cell vehicles. Capacitor reliability is a key challenge for development of high-performance capacitors. In this study, yttrium stabilized zirconia (YSZ) with various yttria concentrations were fabricated and tested for dielectric properties, such as breakdown strength and dielectric loss factors. The results indicated that the breakdown strength as high as 2 MV/cm could be achieved in YSZ samples with 10 mol% yttria. In addition, the dielectric loss factors of the samples were lower than …
N,N’-Bis(3,5-Di-T-Butylsalicylideneimine) Propanediamine And Its Some Tetradentate Schiff Base Complexes Synthesis, Characterization And Thermal Study, Fatih Dogan, M. Ulusoy, O. F. Ozturk, I. Kaya, B. Salih
N,N’-Bis(3,5-Di-T-Butylsalicylideneimine) Propanediamine And Its Some Tetradentate Schiff Base Complexes Synthesis, Characterization And Thermal Study, Fatih Dogan, M. Ulusoy, O. F. Ozturk, I. Kaya, B. Salih
Materials Science and Engineering Faculty Research & Creative Works
Several mononuclear Co (II), Ni (II), Cu (II) and Fe (II) complexes of tetradentate salpren-type diamine, obtained from 3,5-di-tert–butyl-2-hydroxybenzaldehyde and 1,3-diaminopropane have been prepared and characterized by analytical, spectroscopic (FTIR, UV-Vis) techniques, magnetic susceptibility measurements and thermogravimetric analyses (TG). The thermodynamic and thermal properties of complexes have been investigated. For further characterization direct insertion probe-mass spectrometry (DIP-MS) was used and the fragmentation pattern and also stability of the ions were evaluated. The characterization of the end products of the decomposition was achieved by X-ray diffraction. The thermal stabilities of metal complexes of N,N’-bis(3,5-di-t-butylsalicylideneimine) propane diamine ligand (L) were found as …
Nanoparticulate Composites Of Melt Textured Yba2cu3o7−X Superconductors, Oratai Jongprateep, Fatih Dogan
Nanoparticulate Composites Of Melt Textured Yba2cu3o7−X Superconductors, Oratai Jongprateep, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
It has been shown that Nd1+xBa2−xCu3O7−x could exhibit a pronounced Jc(H) peak effect, which results in an enhancement of the critical current density under the medium range magnetic field. Additions of small quantities of Nd2O3 into Pt-doped YBa2Cu3O7−x (Y123) resulted in the formation of nanosized (30–60 nm) secondary phases which are expected to have a significant effect on superconducting properties of melt textured Y123 single crystals. By considering of solidification kinetics, effect of neodymium oxide and platinum addition on processing parameters of melt textured Y123 superconductors are …
Composition Dependence Of The In-Plane Cu-O Bond-Stretching Lo Phonon Mode In Yba2cu3o6+X, F. Stercel, T. Egami, Herbert A. Mook, M. Yethiraj, J.-H. Chung, M. Arai, C. Frost, Fatih Dogan
Composition Dependence Of The In-Plane Cu-O Bond-Stretching Lo Phonon Mode In Yba2cu3o6+X, F. Stercel, T. Egami, Herbert A. Mook, M. Yethiraj, J.-H. Chung, M. Arai, C. Frost, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
An inelastic pulsed neutron scattering study was performed on the dependence of the dispersion and spectral intensity of the in-plane Cu-O bond-stretching LO phonon mode on doped charge density. The measurements were made in the time-of-flight mode with the multiangle position sensitive spectrometer of the ISIS facility on single crystals of YBa2Cu3O6+x x=0.15, 0.35, 0.6, 0.7, and 0.95. The focus of the study is the in-plane Cu-O bond-stretching LO phonon mode, which is known for strong electron-phonon coupling and unusual dependence on composition and temperature. It is shown that the dispersions for the samples with x=0.35, 0.6, and 0.7 are …
Composition Dependence Of The In-Plane Cu-O Bond-Stretching Lo Phonon Mode In YBa2Cu3O6+X, Ferenc Stercel, Takeshi Egami, Herbert A. Mook, Mohana Yethiraj, J-H Chung, M. Arai, C. Frost, Fatih Dogan
Composition Dependence Of The In-Plane Cu-O Bond-Stretching Lo Phonon Mode In YBa2Cu3O6+X, Ferenc Stercel, Takeshi Egami, Herbert A. Mook, Mohana Yethiraj, J-H Chung, M. Arai, C. Frost, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
An inelastic pulsed neutron scattering study was performed on the dependence of the dispersion and spectral intensity of the in-plane Cu-O bond-stretching LO phonon mode on doped charge density. The measurements were made in the time-of-flight mode with the multiangle position sensitive spectrometer of the ISIS facility on single crystals of YBa2Cu3O6+x (x=0.15, 0.35, 0.6, 0.7, and 0.95). The focus of the study is the in-plane Cu-O bond-stretching LO phonon mode, which is known for strong electron-phonon coupling and unusual dependence on composition and temperature. It is shown that the dispersions for the samples with …
Thickness Effects On The Ac And Dc Electrical Behavior Of Rf-Sputtered Batio3 Nano-Capacitors With Pt And Ni Electrodes, James N. Reck, Matthew O'Keefe, Fatih Dogan
Thickness Effects On The Ac And Dc Electrical Behavior Of Rf-Sputtered Batio3 Nano-Capacitors With Pt And Ni Electrodes, James N. Reck, Matthew O'Keefe, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
Nanoscale BaTiO3 capacitors were deposited on Si wafers at dielectric thicknesses of approximately 25, 50, 100, and 200 nm using RF-magnetron sputtering with either 25 nm thick Ni or Pt electrodes. Multiple DC and AC tests were conducted on these devices to determine the effects of BaTiO3 thickness on the measured dielectric behaviors. All films were observed to have non-linear responses for resistance, permittivity, and loss with respect to dielectric thickness. The permittivity was found to follow a standard dead layer model behavior with measured values ranging from approximately 350 to 1700 for Ni electrodes and approximately 100 …
Using Science, Engineering, And Education To Address Water Supply Challenges In The Highlands Of Guatemala, Andrew Curtis Elmore, William Fahrenholtz
Using Science, Engineering, And Education To Address Water Supply Challenges In The Highlands Of Guatemala, Andrew Curtis Elmore, William Fahrenholtz
Materials Science and Engineering Faculty Research & Creative Works
The Guatemalan Highlands is a Popular Destination for Non-Government Organizations Interested in Performing Relief Projects. U.S.-Based Organizations Such as Rotary International, Engineers Without Borders, and Various Religious Organizations Travel to Guatemala to Conduct Humanitarian Activities Which May Be Effective for the Short Term, But It is Not Clear that the Efforts Have a Systematic Impact. Students and Faculty at the University of Missouri-Rolla Have Systematically Studied Water Supply Issues Including Undergraduate and Graduate Research Projects and Undergraduate Engineering Courses Such as International Capstone Design. Materials Engineers Have Been Involved in the Study of Ceramic-Based Water Treatment Devices. These Microfilters Have …
Enhanced Shrinkage Of Lanthanum Strontium Manganite (La0.90sr0.10mno3+Δ) Resulting From Thermal And Oxygen Partial Pressure Cycling, Benjamin P. Mccarthy, Larry R. Pederson, Harlan U. Anderson, Xiao Dong Zhou, Prabhakar Singh, Gregory W. Coffey, Edwin C. Thomsen
Enhanced Shrinkage Of Lanthanum Strontium Manganite (La0.90sr0.10mno3+Δ) Resulting From Thermal And Oxygen Partial Pressure Cycling, Benjamin P. Mccarthy, Larry R. Pederson, Harlan U. Anderson, Xiao Dong Zhou, Prabhakar Singh, Gregory W. Coffey, Edwin C. Thomsen
Materials Science and Engineering Faculty Research & Creative Works
Exposure of (La0.90Sr0.10)0.98MnO3+δ (LSM-10) to repeated oxygen partial pressure cycles (air/10 ppm O2) resulted in enhanced densification rates, similar to behavior shown previously due to thermal cycling. Shrinkage rates in the temperature range 700°-1000°C were orders of magnitude higher than Makipirtti-Meng model estimations based on stepwise isothermal dilatometry results at a high temperature. a maximum in enhanced shrinkage due to oxygen partial pressure cycling occurred at 900°C. Shrinkage was the greatest when LSM-10 bars that were first equilibrated in air were exposed to gas flows of lower oxygen fugacity than in …
Transportation Fuel Research And Development: Statistically Validated Codes And Standards, Fatih Dogan
Transportation Fuel Research And Development: Statistically Validated Codes And Standards, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
The recent establishment of the National University Transportation Center at MST under the "Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users," expands the research and education activities to include alternative transportation fuels and other issues that are at the forefront of society and the national agenda. UMR in partnership with MTI will establish a rural hydrogen transportation test bed for developing, demonstrating, evaluating, and promoting hydrogen-based technologies in a real-world environment. The State of Missouri is ideally suited to develop and demonstrate the proper operation of hydrogen highways in a rural setting, which represents over 25 percent …
Effects Of Surface-Deposited Nanocrystalline Chromite Thin Films On The Performance Of A Ferritic Interconnect Alloy, I. Belogolovsky, X. D. Zhou, H. Kurokawa, P. Y. Hou, S. Visco, H. U. Anderson
Effects Of Surface-Deposited Nanocrystalline Chromite Thin Films On The Performance Of A Ferritic Interconnect Alloy, I. Belogolovsky, X. D. Zhou, H. Kurokawa, P. Y. Hou, S. Visco, H. U. Anderson
Materials Science and Engineering Faculty Research & Creative Works
LaCrO3 -Based nanocrystalline thin films, substituted with Sr and Zn and coated onto a Fe-26 atom % Cr Ebrite alloy were evaluated at 750-900°C as potential enhancers of oxide properties in ferritic alloy interconnects of a solid oxide fuel cell. It was found that at 750°C the coatings provided (i) lower oxidation rates, (ii) increased electrical conductivity, (iii) protection during 24 h cycling and at least 2375 h of isothermal oxidation, and (iv) a fine-grained and uniform oxide microstructure. Although after oxidation at 850°C the grains grew substantially and the scale seemed to be overgrowing the film, conductivity and …
Enhancement Of Crystal Growth And Superconducting Properties Of Melt-Textured Yba2cu3o7−X Through Addition Of Baceo3 And Basno3, Oratai Jongprateep, Fatih Dogan
Enhancement Of Crystal Growth And Superconducting Properties Of Melt-Textured Yba2cu3o7−X Through Addition Of Baceo3 And Basno3, Oratai Jongprateep, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
The effects of additions of BaSnO3 in combination with BaCeO3 on the microstructure, crystal growth and superconducting properties of melt-textured YBa2Cu3O7−x (Y123) have been investigated. It has been reported that the addition of BaCeO3 to Y123 results in an increase in the critical current density. However, higher cerium concentrations affect the solidification process and inhibit the growth of melt-textured Y123 single crystals. BaSnO3 has been shown to restore the properties of Y123 with BaCeO3 additives. Increasing the amount of added BaSnO3 leads to refinement of Y211 particles, enhancement of …
Freeze-Spray Processing Of Layered Ceramic Composites, Qiang Fu, Oratai Jongprateep, Ashlee Abbott, Fatih Dogan
Freeze-Spray Processing Of Layered Ceramic Composites, Qiang Fu, Oratai Jongprateep, Ashlee Abbott, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
Thermal gradients and associated stresses are critical in designing with ceramic composites having low thermal conductivity. In order to reduce the stresses from thermal gradients, compositional gradients are employed in designing of composite structures. This study addresses development of freeze-spray process to fabricate layered ceramic structures with controlled layer thickness and microstructural development. The composites were processed by spraying of ceramic slurries with low binder content and relatively high solids loadings (up to 40 vol%) on a cooled substrate. The frozen parts were freeze-dried and sintered at elevated temperatures. The relationship between microstructural development and thermal expansion behavior of Al …
Freeze-Spray Processing Of Layered Ceramic Composites (Preprint), Oratai Jongprateep, Q. Fu, A. Abbott, Fatih Dogan
Freeze-Spray Processing Of Layered Ceramic Composites (Preprint), Oratai Jongprateep, Q. Fu, A. Abbott, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
Thermal gradients and associated stresses are critical in designing with ceramic composites having low thermal conductivity. In order to reduce the stresses from thermal gradients, compositional gradients are employed in designing of composite structures. This study addresses development of freeze-spray process to fabricate layered ceramic structures with controlled layer thickness and microstructural development. The composites were processed by spraying of ceramic slurries with low binder content and relatively high solids loadings up to 40 vol on a cooled substrate. The frozen parts were freeze-dried and sintered at elevated temperatures. The relationship between microstructural development and thermal expansion behavior of Al …
Effect Of Nozzle Base Material On The Rate Of Clogging During The Continuous Casting Of Aluminum-Killed Steels, Luis Trueba, Kent D. Peaslee, Jeffrey D. Smith, Musa Karakus
Effect Of Nozzle Base Material On The Rate Of Clogging During The Continuous Casting Of Aluminum-Killed Steels, Luis Trueba, Kent D. Peaslee, Jeffrey D. Smith, Musa Karakus
Materials Science and Engineering Faculty Research & Creative Works
One approach to solving the problem of nozzle clogging during the continuous casting of aluminum-killed steels is through careful selection of nozzle materials. in this study, the rate of clogging was measured while casting steel through simulated nozzles produced from alumina, zirconia, magnesia, zirconia-graphite, and alumina-graphite - three common base materials and two common carbon-containing nozzle materials. Spent nozzles were characterized using optical and cathodoluminescence microscopy. Interactions between the nozzles and steel were not observed in the alumina, zirconia, and zirconia-graphite nozzles. Slight interactions were observed in the magnesia nozzles as alumina inclusions within the steel interacted with the nozzle …
Effect Of Baceo3 And Basno3 Additives On Microstructural Development And Critical Current Density Of Melt Textured Yba2cu3o7-X, Oratai Jongprateep, Fatih Dogan, Michael Strasik, Kevin E. Mccrary
Effect Of Baceo3 And Basno3 Additives On Microstructural Development And Critical Current Density Of Melt Textured Yba2cu3o7-X, Oratai Jongprateep, Fatih Dogan, Michael Strasik, Kevin E. Mccrary
Materials Science and Engineering Faculty Research & Creative Works
Improvement of superconducting properties, such as critical current density Jc and trapped magnetic field, of melt textured YBa2Cu3O7-x (Y123) require introducing of effective pinning sites, e.g., nonsuperconducting inclusions, twin boundaries and other defects. It has been shown that addition of small quantities of BaCeO3 (< 0.5 wt.%) into Y123 results in an increase of the J/sub c/. However, higher cerium concentrations affect the solidification process and inhibit the growth of melt textured Y123 single crystals. In this study, the effect of BaCeO/sub 3/ additions on the growth and microstructural development of melt textured Y123 single crystals were investigated. The relationship between the solidification kinetics, microstructural development and superconducting properties of Y123 melt textured single crystals with cerium additives is discussed.
The Wettability Of Titanium Diboride By Molten Aluminum Drops, D. A. Weirauch, W. J. Krafick, G. Ackart, P. D. Ownby
The Wettability Of Titanium Diboride By Molten Aluminum Drops, D. A. Weirauch, W. J. Krafick, G. Ackart, P. D. Ownby
Materials Science and Engineering Faculty Research & Creative Works
Titanium diboride is widely accepted to be completely wet by liquid aluminum, yet few published wetting studies demonstrate this behavior, and reported contact angles vary widely. Sessile drop substrates from four different sources were selected and their microstructures and chemistries characterized. the results of sessile drop experiments using four techniques to modify oxide film behavior were compared. the Al-TiB2 interfaces were examined in metallographic sections or after chemical removal of the Al drop. Al wets a material containing 5.5 wt% Ni in vacuum experiments before the hold temperature of 1025°C is reached. the other TiB2 substrates are completely wet by …
Continuous Solidification Of Yba2cu3o7−X By Isothermal Undercooling, Fatih Dogan
Continuous Solidification Of Yba2cu3o7−X By Isothermal Undercooling, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
Growth kinetics and microstructural development of single crystal YBa2Cu3O7−x (Y123) superconductors, prepared by a melt texturing method under isothermal undercooling conditions, were investigated. At small undercooling, ΔT = 6 K, the initial growth of Y123 crystal was terminated at a size of ∼8 mm × 8 mm in the semisolid phase before the entire sample was fully solidified through the peritectic reaction. With incremental increase of ΔT, the growth of the crystal continued so that the whole sample (22 mm diameter and 8 mm thickness) solidified as a single crystal. Termination of the crystal growth …
Single Chamber Electrolyte Supported Sofc Module, Toshio Suzuki, Piotr Jasinski, Harlan U. Anderson, Fatih Dogan
Single Chamber Electrolyte Supported Sofc Module, Toshio Suzuki, Piotr Jasinski, Harlan U. Anderson, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
An electrolyte supported single chamber solid oxide fuel cell (SOFC) module consisting of two cells has been proposed. The module consists of one Sm-doped CeO2 (SDC) electrolyte substrate (0.5 mm thick with the size of 5 3 10 mm), two Ni-SDC anodes on one side, and two SDC-(La,Sr)(Co,Fe)O3 cathodes on the other side. Two modules with different electrode areas were prepared and tested using an air-propane mixture. The electrode area had a strong influence on the performance of the module. It was shown that the two-cell module generated 1.5 V open-circuit voltage and about 17 mW maximum power …
Defect Chemistry Of Mixed Ionic/Electronic P-Type Oxides, Harlan U. Anderson, Xiao-Dong Zhou, Fatih Dogan
Defect Chemistry Of Mixed Ionic/Electronic P-Type Oxides, Harlan U. Anderson, Xiao-Dong Zhou, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
The p-type perovskite structure oxides are finding use in a number of energy related applications. In particular they are being used as cathodes in fuel cells as well as dense oxygen separation membranes. The defect concentration and defect mobility determine the electrical properties. Since both of these are dependent upon the operating temperature and oxygen activity, it is important to understand how an oxide equilibrates with its environment. In this paper, a defect chemistry model for the oxidation-reduction behavior of p-type perovskites is reviewed with formulations in the (La,Sr)(Cr,Mn,Co,Fe)03 system being used as examples.
Anode Supported Single Chamber Solid Oxide Fuel Cell In Ch 4 -Air Mixture, Toshio Suzuki, Piotr Jasinski, Vladimir Petrovsky, Harlan U. Anderson, Fatih Dogan
Anode Supported Single Chamber Solid Oxide Fuel Cell In Ch 4 -Air Mixture, Toshio Suzuki, Piotr Jasinski, Vladimir Petrovsky, Harlan U. Anderson, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
In this study, yttrium-stabilized zirconia (YSZ) thin films 1-2 μm thick electrolyte have been prepared using NiO-YSZ anode as substrates. Fuel cell test was conducted with the single chamber configuration in methane-air gas mixture using (la,Sr)(Co,Fe) O3 (LSCF) as the cathode. Test results showed that the open-circuit voltage to be >0.8 V, with power density as high as 0.12 W cm−2. It was also shown that gas flow rate has a large influence on the performance of the fuel cell, which indicates the importance of the geometrical design for anode support fuel cell system.
Mixed Ion-Polaron Transport In Na2o-Pbo-Fe2o3-P2o5 Glasses, A. Moguš-Milanković, A. Šantić, Signo Tadeu Dos Reis, K. Furić, D. E. Day
Mixed Ion-Polaron Transport In Na2o-Pbo-Fe2o3-P2o5 Glasses, A. Moguš-Milanković, A. Šantić, Signo Tadeu Dos Reis, K. Furić, D. E. Day
Materials Science and Engineering Faculty Research & Creative Works
The electrical and dielectric properties of the xNa2O · (100 - x) · [28.3PbO · 28.7Fe2O3 · 43.0P2O5] (0 ≤ x ≤ 30) glasses were measured by impedance spectroscopy in the frequency range from 0.01 Hz to 3 MHz and the temperature range from 303 to 473 K. the conductivity for glasses containing ≤15 mol% Na2O is predominantly electronic and is controlled by electron hopping between Fe(II) and Fe(III) ions. in these glasses the sodium ions have such a low mobility, caused by ion-polaron interaction, that they make no …
The Structure Of The High-Energy Spin Excitations In A High-Transition-Temperature Superconductor, S. M. Hayden, H. A. Mook, Pengcheng Dal, T. G. Perring, F. Doǧan
The Structure Of The High-Energy Spin Excitations In A High-Transition-Temperature Superconductor, S. M. Hayden, H. A. Mook, Pengcheng Dal, T. G. Perring, F. Doǧan
Materials Science and Engineering Faculty Research & Creative Works
In conventional superconductors, lattice vibrations (phonons) mediate the attraction between electrons that is responsible for superconductivity. The high transition temperatures (high-Tc) of the copper oxide superconductors has led to collective spin excitations being proposed as the mediating excitations in these materials. The mediating excitations must be strongly coupled to the conduction electrons, have energy greater than the pairing energy, and be present at Tc. The most obvious feature in the magnetic excitations of high-Tc superconductors such as YBa 2Cu3O6+x is the so-called 'resonance'. Although the resonance may be strongly coupled to the superconductivity, it is unlikely to be the main …
Polarized Neutron Measurement Of Magnetic Order In Yba2Cu3O6.45, Herbert A. Mook, Pengcheng Dai, Stephen M. Hayden, Arno Hiess, Sh Lee, Fatih Dogan
Polarized Neutron Measurement Of Magnetic Order In Yba2Cu3O6.45, Herbert A. Mook, Pengcheng Dai, Stephen M. Hayden, Arno Hiess, Sh Lee, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
Orbital current order of the d-density-wave type has been postulated to explain the pseudo gap in high temperature superconductors. We have performed neutron scattering experiments to search for this order and show here the results obtained on an YBa2Cu3O6.45 sample using the best neutron spectrometers available. We argue that the data are consistent with a small, largely c-axis-directed moment, found below about 200 K.
Bioactive Materials, D. E. Day, Erik M. Erbe, Marina Richard, Joshua A. Wojcik
Bioactive Materials, D. E. Day, Erik M. Erbe, Marina Richard, Joshua A. Wojcik
Materials Science and Engineering Faculty Research & Creative Works
Bioactive substantially silica-free glass material with a hydroxyapatite layer thereon is described, as well as methods for producing hydroxyapatite on a borate glass.
Chemical Solution Deposition Of Electronic Oxide Films, Robert W. Schwartz, Theodor Schneller, Rainer Waser
Chemical Solution Deposition Of Electronic Oxide Films, Robert W. Schwartz, Theodor Schneller, Rainer Waser
Materials Science and Engineering Faculty Research & Creative Works
The chemical solution deposition (CSD) technique as a highly flexible method for the fabrication of electronic oxide thin films is reviewed. Various chemical aspects of different approaches are discussed, including sol-gel, hybrid, and metallo-organic decomposition (MOD) routes, which all have been successfully applied for the deposition of this class of materials. Principles of the selection and properties of the educts, the mechanism of film crystallization, and tailoring of microstructure through manipulation of deposition parameters are reported. the role of thermodynamics on the phase transformation process is also reviewed. Finally, some of the applications for chemical solution-derived thin films currently under …
Neodymium Oxide Doped Melt Textured Yba2cu3o7-X Single Crystals, Fatih Dogan, Stephen W. Sofie, William C. Hicks, Michael Strasik, Kevin E. Mccrary, Arthur C. Day
Neodymium Oxide Doped Melt Textured Yba2cu3o7-X Single Crystals, Fatih Dogan, Stephen W. Sofie, William C. Hicks, Michael Strasik, Kevin E. Mccrary, Arthur C. Day
Materials Science and Engineering Faculty Research & Creative Works
Processing, microstructure and property relationships in neodymium oxide doped high temperature superconducting YBa2Cu3O7-x were investigated. It has been observed that a small amount (0.25–1 mol%) of Nd2O3 results in the formation of nanosized secondary phases which may have a significant effect on the superconducting properties of melt textured Y123 single crystals. It was further observed that addition of Nd2O3 greater than 1 mol% leads to multiple nucleation during solidification of Y123 and results in polycrystalline samples. Melt textured single crystals of Y123 with 1 mol% were successfully grown and …
Neodymium Oxide Doped Melt Textured Yba2cu3o7-X Single Crystals, Fatih Dogan, Stephen W. Sofie, William C. Hicks, Michael Strasik, Kevin E. Mccrary, Arthur C. Day
Neodymium Oxide Doped Melt Textured Yba2cu3o7-X Single Crystals, Fatih Dogan, Stephen W. Sofie, William C. Hicks, Michael Strasik, Kevin E. Mccrary, Arthur C. Day
Materials Science and Engineering Faculty Research & Creative Works
Processing, microstructure and property relationships in neodymium oxide doped high temperature superconducting YBa2Cu3O7-x (Y123) were investigated. It has been observed that a small amount (/spl sim/ 0.25 - 1 mol%) of Nd2O3 results in the formation of nanosized secondary phases which may have a significant effect on the superconducting properties of melt textured Y123 single crystals. It was further observed that addition of Nd2O3 greater than 1 mol% leads to multiple nucleation during solidification of Y123 and results in polycrystalline samples. Melt textured single crystals of Y123 with < 1 mol% were successfully grown and characterized with respect to microstructural development and superconducting properties.
Electron Microscopy Studies On Platinum-Ceramics Nanocomposites Synthesized By Spray Process, X.-D. Zhou
Electron Microscopy Studies On Platinum-Ceramics Nanocomposites Synthesized By Spray Process, X.-D. Zhou
Materials Science and Engineering Faculty Research & Creative Works
The platinum-ceramics nanocomposites synthesized by spray process were discussed using electron microscopy. It was found that the nanocomposites of Pt-ceramics were synthesized by spray process with a controllable distribution of Pt primary particles. the analysis showed that the nanometer Pt primary particles encapsulating YSZ nanocomposites were derived when ethanol was used as solvent.