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Articles 571 - 600 of 1337

Full-Text Articles in Ceramic Materials

The Wettability Of Titanium Diboride By Molten Aluminum Drops, D. A. Weirauch, W. J. Krafick, G. Ackart, P. D. Ownby May 2005

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 …

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Dissolution, Reactor, And Environmental Behavior Of Zro2-Mgo Inert Fuel Matrix: Quarterly Report, January 2005 To March 2005, Earl Wolfram, Thomas Hartmann, Kenneth Czerwinski Mar 2005

Dissolution, Reactor, And Environmental Behavior Of Zro2-Mgo Inert Fuel Matrix: Quarterly Report, January 2005 To March 2005, Earl Wolfram, Thomas Hartmann, Kenneth Czerwinski

Fuels Campaign (TRP)

This project will examine inert matrix fuels containing ZrO2 and MgO as the inert matrix, with the relative amount of MgO varied from 30% to 70% in ZrO2. Reactor physics calculations will be used to examine suitable quantities of burnable poisons from the candidate elements Gd, Er, or Hf with reactor grade Pu providing the fissile component, with up to 10% of 239Pu. Ceramics will be synthesized and characterized based on the reactor physics results. The solubility the fuel ceramics, in reactor conditions, reprocessing conditions, and repository conditions, will be investigated in a manner to provide …

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Continuous Solidification Of Yba2cu3o7−X By Isothermal Undercooling, Fatih Dogan Jan 2005

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 …

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Dissolution, Reactor, And Environmental Behavior Of Zro2-Mgo Inert Fuel Matrix, Kenneth Czerwinski Jan 2005

Dissolution, Reactor, And Environmental Behavior Of Zro2-Mgo Inert Fuel Matrix, Kenneth Czerwinski

Fuels Campaign (TRP)

This project examines inert fuels containing ZrO2 and MgO as the inert matrix, with the relative amount of MgO varied from 30% to 70% in ZrO2. Reactor physics calculations are used to examine suitable quantities of burnable poisons from the candidate elements Gd, Er, or Hf with reactor grade Pu providing the fissile component, with up to 10% of 239Pu. Ceramics are synthesized and characterized based on the reactor physics results. The solubility of the fuel ceramics, in reactor conditions, reprocessing conditions, and repository conditions, are investigated in a manner to provide thermodynamic data necessary for …

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Development, Fabrication And Study Of Fullerene-Containing Carbon Material (Fcc) For Immobilization Of Iodine: Progress Report #1-4, Michael Savopulo, Boris E. Burakov Jan 2005

Development, Fabrication And Study Of Fullerene-Containing Carbon Material (Fcc) For Immobilization Of Iodine: Progress Report #1-4, Michael Savopulo, Boris E. Burakov

Separations Campaign (TRP)

During current reporting period the experiments on synthesis of ceramic-like material by conversion of iodine-doped FCC and activated carbon to SixCy have been completed. Cold pressed granules of FCC and activated carbon were rinsed in water-ethanol solution of tetraethoxysilane (TEOS), Si(OC2H5)4, and then used for further synthesis. All new samples obtained have been studied using precise powder XRD analysis.

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Single Chamber Electrolyte Supported Sofc Module, Toshio Suzuki, Piotr Jasinski, Harlan U. Anderson, Fatih Dogan Nov 2004

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 …

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Defect Chemistry Of Mixed Ionic/Electronic P-Type Oxides, Harlan U. Anderson, Xiao-Dong Zhou, Fatih Dogan Sep 2004

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.

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Anode Supported Single Chamber Solid Oxide Fuel Cell In Ch 4 -Air Mixture, Toshio Suzuki, Piotr Jasinski, Vladimir Petrovsky, Harlan U. Anderson, Fatih Dogan Sep 2004

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.

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Mixed Ion-Polaron Transport In Na2o-Pbo-Fe2o3-P2o5 Glasses, A. Moguš-Milanković, A. Šantić, Signo Tadeu Dos Reis, K. Furić, D. E. Day Aug 2004

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 …

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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 Jun 2004

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 …

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Polarized Neutron Measurement Of Magnetic Order In Yba2⁢Cu3⁢O6.45, Herbert A. Mook, Pengcheng Dai, Stephen M. Hayden, Arno Hiess, Sh Lee, Fatih Dogan Apr 2004

Polarized Neutron Measurement Of Magnetic Order In Yba2⁢Cu3⁢O6.45, 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 YBa2⁢Cu3⁢O6.45 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.

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Bioactive Materials, D. E. Day, Erik M. Erbe, Marina Richard, Joshua A. Wojcik Mar 2004

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.

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Monotonic, Creep-Rupture, And Fatigue Behavior Of Carbon Fiber Reinforced Silicon Carbide (C/Sic) At An Elevated Temperature, John M. Engesser Mar 2004

Monotonic, Creep-Rupture, And Fatigue Behavior Of Carbon Fiber Reinforced Silicon Carbide (C/Sic) At An Elevated Temperature, John M. Engesser

Theses and Dissertations

The main objective of this research effort was to examine the impact that cyclic loading frequency has on the life of a C/SiC composite at an elevated temperature of 550°C. Cyclic loading of C/SiC was investigated at frequencies of 375 Hz, 10 Hz, 1 Hz, and 0.1 Hz. Creep-Rupture tests and tests that were combinations of creep-rupture and fatigue were also accomplished. A monotonic tensile test was performed at 550°C and compared to a room temperature monotonic test. This study showed that an elevated temperature of 550°C has very little effect on the Ultimate Tensile Strength (UTS) of C/SiC. The …

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Preparation Of (Pb,Ba)Tio3 Powders And Highly Oriented Thin Films By A Sol-Gel Process, Stacey Boland, Suresh Pillai, Wein-Duo Yang, Sossina Haile Jan 2004

Preparation Of (Pb,Ba)Tio3 Powders And Highly Oriented Thin Films By A Sol-Gel Process, Stacey Boland, Suresh Pillai, Wein-Duo Yang, Sossina Haile

Articles

Solid solution Pb1-xBaxTiO3, with particular emphasis on Pb0.5Ba0.5TiO3, was prepared
using a sol-gel process incorporating lead acetate trihydrate, barium acetate, and
titanium isopropoxide as precursors, acetylacetone (2,4 pentanedione) as a chelating
agent, and ethylene glycol as a solvent. The synthesis procedure was optimized by
systematically varying acetylacetone: Ti and H2O:Ti molar ratios and calcination
temperature. The resulting effects on sol and powder properties were studied using
thermogravimetric analysis/differential scanning calorimetry, Fourier transform infrared
spectroscopy, Brunauer-Emmett-Teller analysis, and x-ray diffraction (XRD).
Crystallization of the perovskite structure occurred at a temperature as low as 450 °C.
Thin films were prepared by spin …

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Chemical Solution Deposition Of Electronic Oxide Films, Robert W. Schwartz, Theodor Schneller, Rainer Waser Jan 2004

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 …

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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 Jun 2003

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 …

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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 Jun 2003

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.

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Electron Microscopy Studies On Platinum-Ceramics Nanocomposites Synthesized By Spray Process, X.-D. Zhou Feb 2003

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.

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In-Plane Anisotropy And Temperature Dependence Of Oxygen Phonon Modes In Yba2⁢Cu3⁢O6.95, J-H Chung, Takeshi Egami, Rj Mcqueeney, Mohana Yethiraj, Masatoshi Arai, Tetsuya Yokoo, Y. Petrov, Herbert A. Mook, Yasuo Endoh, Setsuko Tajima, C. Frost, Fatih Dogan Jan 2003

In-Plane Anisotropy And Temperature Dependence Of Oxygen Phonon Modes In Yba2⁢Cu3⁢O6.95, J-H Chung, Takeshi Egami, Rj Mcqueeney, Mohana Yethiraj, Masatoshi Arai, Tetsuya Yokoo, Y. Petrov, Herbert A. Mook, Yasuo Endoh, Setsuko Tajima, C. Frost, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

Inelastic pulsed neutron scattering measurements on YBa2⁢Cu3⁢O6.95 single crystals indicate that the sample has a distinct a-b plane anisotropy in the oxygen vibrations. The Cu-O bond-stretching-type phonons, which are suspected to interact strongly with charge, are simultaneously observed along the a and b directions due to a 7-meV splitting arising from the orthorhombicity, even though the sample is twinned. The bond-stretching LO branch with the polarization along a (perpendicular to the chain) loses intensity beyond the middle of the zone, indicating branch splitting as seen in doped nickelates, with the second branch being located at …

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Comparison Of Anode And Electrolyte Support Configuration Of Single-Chamber Sofc, Piotr Jasinski, Toshio Suzuki, Zach Byars, Fatih Dogan, Harlan A. Anderson Jan 2003

Comparison Of Anode And Electrolyte Support Configuration Of Single-Chamber Sofc, Piotr Jasinski, Toshio Suzuki, Zach Byars, Fatih Dogan, Harlan A. Anderson

Materials Science and Engineering Faculty Research & Creative Works

The single-chamber solid oxide fuel cell (SOFC) has recently received considerable attention. This type of fuel cell operates in the mixed reactant gas and therefore does not require separation of the fuel and oxidant gases. In this paper we report the anode- and electrolyte-supported configurations of the single chamber SOFC that we have studied. The system based on typical fuel cell composition has been examined: yttrium stabilized zirconia (YSZ) as an electrolyte, nickel/YSZ cermet as an anode, lanthanum strontium manganese oxide (LSM) as a cathode. The cells were prepared by tape-casting and screen-printing techniques. The cathode processing parameters have been …

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Phase Diagram For Stripes In Yba2cu3o6+X Superconductors, Herbert A. Mook, Fatih Dogan Dec 2002

Phase Diagram For Stripes In Yba2cu3o6+X Superconductors, Herbert A. Mook, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

Neutron scattering has been used to measure the charge and spin structure in the YBa2Cu3O6+x superconductors. Incommensurate static charge ordering is found at low doping levels while only charge fluctuations are found at higher doping. The spin structure is complex with both a commensurate resonance and incommensurate structure observed at low temperatures. The scattering results are used to construct a phase diagram for stripes in the YBa2Cu3O6+x system.

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Magnetic Order In Yba2⁢Cu3⁢O6+X Superconductors, Herbert A. Mook, Pengcheng Dai, Stephen M. Hayden, Arno Hiess, Jw Lynn, S-H Lee, Fatih Dogan Oct 2002

Magnetic Order In Yba2⁢Cu3⁢O6+X Superconductors, Herbert A. Mook, Pengcheng Dai, Stephen M. Hayden, Arno Hiess, Jw Lynn, S-H Lee, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

Polarized and unpolarized neutron diffraction has been used to search for magnetic order in YBa2⁢Cu3⁢O6+x superconductors. Most of the measurements were made on a high-quality crystal of YBa2⁢Cu3⁢O6.6. It is shown that this crystal has highly ordered ortho-II chain order, and a sharp superconducting transition. Inelastic scattering measurements display a very clean spin-gap and pseudo gap with any intensity at 10 meV being 50 times smaller than the resonance intensity. The crystal shows a complicated magnetic order that appears to have three components. A magnetic phase is found at …

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Phonon Dispersion Measurements Of Yba2cu3o6.15 And Yba2cu3o6.95 By Time-Of-Flight Neutron Spectroscopy, J-H Chung, T. Egami, R. J. Mcqueeney, M. Yethiraj, M. Arai, T. Yokoo, Herbert A. Mook, Y. Endoh, S. Tajima, C. Frost, Fatih Dogan Oct 2002

Phonon Dispersion Measurements Of Yba2cu3o6.15 And Yba2cu3o6.95 By Time-Of-Flight Neutron Spectroscopy, J-H Chung, T. Egami, R. J. Mcqueeney, M. Yethiraj, M. Arai, T. Yokoo, Herbert A. Mook, Y. Endoh, S. Tajima, C. Frost, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

We measured the phonon dispersions of YBa2Cu3O6.15 and YBa2Cu3O6.95 by time-of-flight inelastic neutron scattering. The in-plane bond-stretching modes in the metallic phase showed a distinct a-b plane an isotropy beyond what is expected for structural origin. Such an isotropy in the longitudinal optical modes, which is absent in the TO, suggests strong in-plane anisotropy in the underlying electronic structure. Apical oxygen bond-stretching modes showed a large frequency change between the insulating and the metallic phases. This large softening also is beyond structural origin, and suggests the effect of local electronic …

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Method For Sintering Ceramic Tapes, Fatih Dogan, Jian-Huei Feng, Lucian G. Ferguson Sep 2002

Method For Sintering Ceramic Tapes, Fatih Dogan, Jian-Huei Feng, Lucian G. Ferguson

Materials Science and Engineering Faculty Research & Creative Works

Flexible Setter powder deposition sheets containing Setter powders were developed for Sintering of ceramic articles including tapes by an economical, fast and Simple method. The sheets provide for deposition of a thin and uniform layer of Setter powders on a green ceramic article after burnout of a binder in the sheet. Because of high Strength and low burnout temperature, hydroxypropyl methylcellulose binder is preferred for production of these sheets. Tape cast sheets with low Solids loading can be obtained by optimizing the wetting behavior of aqueous slurries on tape carrier. Setter, powder deposition sheets are of particular benefit in processing …

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Dopant Effect On Local Dielectric Properties In Barium Titanate Based Electroceramics Determined By Transmission Eels, Kalpana S. Katti, Maoxu Quian, Fatih Dogan, Mehmet Sarikaya Sep 2002

Dopant Effect On Local Dielectric Properties In Barium Titanate Based Electroceramics Determined By Transmission Eels, Kalpana S. Katti, Maoxu Quian, Fatih Dogan, Mehmet Sarikaya

Materials Science and Engineering Faculty Research & Creative Works

Investigates the local electronic excitations of barium titanate electro ceramic using low-loss electron energy loss spectroscopy. Process for monitoring of electronic structure of titanate; Changes in valence and conduction band states by valence state of barium; Shift of oscillator strengths of excitations in local regions.

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Electron–Phonon Interactions In Htsc Cuprates, Takeshi Egami, J-H Chung, Rj Mcqueeney, Mohana Yethiraj, Herbert A. Mook, C. Frost, Y. Petrov, Fatih Dogan, Yasuhiro Inamura, Masatoshi Arai, Setsuuko Tajima, Yasuo Endoh May 2002

Electron–Phonon Interactions In Htsc Cuprates, Takeshi Egami, J-H Chung, Rj Mcqueeney, Mohana Yethiraj, Herbert A. Mook, C. Frost, Y. Petrov, Fatih Dogan, Yasuhiro Inamura, Masatoshi Arai, Setsuuko Tajima, Yasuo Endoh

Materials Science and Engineering Faculty Research & Creative Works

Phonons have been generally considered to be irrelevant to the high-temperature superconductivity in the cuprates. However, such a bias is usually based upon the assumption of conventional electron–phonon coupling, while in the cuprates the coupling can be rather unconventional because of strong electron correlation. We present the results of our recent measurements of phonon dispersion in YBa2Cu3O6+x by inelastic neutron scattering. These suggest certain phonon modes interact strongly with electrons and are closely involved in the superconductivity phenomenon with possible contribution to pairing.

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Biodegradable Glass Compositions And Methods For Radiation Therapy, D. E. Day, James E. White Apr 2002

Biodegradable Glass Compositions And Methods For Radiation Therapy, D. E. Day, James E. White

Materials Science and Engineering Faculty Research & Creative Works

A nonradioactive glass in particulate form adapted for radiation therapy in a mammal comprise a biodegradable rare earth-lithium borate glass material of a specified composition which, upon being subjected to an effective amount of neutron irradiation, will produce a beta or gamma emitting radioisotope, the radioisotope being distributed throughout the glass material, the glass upon being introduced into a body fluid for radiation therapy being adapted to react therewith causing the radioisotope to form an insoluble compound on the surface of the glass material which is retained in the glass material and thereby prevented from escaping from the treatment site. …

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Spectral Analysis Of Transition Metal-Doped Mgo “Matched Emitters” For Thermophotovoltaic Energy Conversion, Lucian G. Ferguson, Fatih Dogan Apr 2002

Spectral Analysis Of Transition Metal-Doped Mgo “Matched Emitters” For Thermophotovoltaic Energy Conversion, Lucian G. Ferguson, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

A new, thermally excited Co/Ni-doped MgO ceramic emitter for TPV energy conversion is described in this work and termed the “matched emitter” because its emissive power spectrum is very efficiently matched with the portion of the electromagnetic spectrum that can be converted directly into electrical energy by infrared responding GaSb photovoltaic cells. Ligand Field Theory calculations are used to estimate the crystal field splitting energies at high temperatures for Co and Ni-doped MgO matched emitters. Experimental measurements of the high temperature (1300–1400◦C) emissive power spectrums for Co and Ni-doped MgO emitters are compared with predictions obtained from ligand field calculations …

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Synthesis Of Pmma-Ceramics Nanocomposites By Spray Process, X.-D. Zhou, H. C. Gu Apr 2002

Synthesis Of Pmma-Ceramics Nanocomposites By Spray Process, X.-D. Zhou, H. C. Gu

Materials Science and Engineering Faculty Research & Creative Works

PMMA-ceramics nanocomposites particles were synthesized by a spray process. PMMA-ZnO compositions showed a higher homogeneous than PMMA-SiO2. The surface of PMMA-SiO2 composites was SiO2 rich. Donut shape particles were formed at high gas flow rate, which was due to the competition between surface tension and dragging force. The Zeta potential dramatically changed in PMMA-ZnO composites whereas there was a slight change in PMMA-SiO2 system.

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Method For Preparing Porous Shells Or Gels From Glass Particles, D. E. Day, Samuel D. Conzone Mar 2002

Method For Preparing Porous Shells Or Gels From Glass Particles, D. E. Day, Samuel D. Conzone

Materials Science and Engineering Faculty Research & Creative Works

A method is provided for preparing shells, concentric shells or porous, homogenous gels from alkali borate glass particles at low temperatures (i.e. room temperature or less than above 100° C.). The alkali borate glass particles contain one or more cations such as aluminum which react with an aqueous solution containing an anion such as hydroxide to form an aqueous insoluble material having a solubility limit of less than about 0.01 wt. percent. TTie resulting shells or gels may be used in many different applications such as a filler in resins, as filters, precursors for nano-sized powders, as thin surface films …

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