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Practical superconductor development for electrical power applications - quarterly report for the period ending June 30, 2003.

Description: This is a multiyear experimental research program that focuses on improving relevant material properties of high-critical temperature (T{sub c}) superconductors and developing fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of the Argonne National Laboratory (ANL) program. A transport critical current density (J{sub c}) of 1.2 x 10{sup 6} A/cm{sup 2} was measured with a sample made with the standard inclined substrate deposition (ISD) architecture. Recent results are described from a study of SrRuO{sub 3} (SRO), a potential alternative buffer layer in coated conductors made by the inclined substrate deposition (ISD) method. Basic features of Raman microscopy are also discussed, and results are presented from a detailed Raman microprobe study of a 1.25-m-long YBCO coated conductor specimen produced at Oak Ridge National Laboratory (ORNL). Strain tolerance data are presented as a function of YBCO thickness for coated conductors with the standard ISD architecture.
Date: September 16, 2003
Creator: Dorris, S. E.
Partner: UNT Libraries Government Documents Department

Practical superconductor development for electrical power applications - quarterly report for the period ending March 31, 2004.

Description: This is a multiyear experimental research program that focuses on improving relevant material properties of high-critical-temperature (Tc) superconductors and developing fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of the Argonne National Laboratory (ANL) program.
Date: July 21, 2004
Creator: Dorris, S. E.
Partner: UNT Libraries Government Documents Department

Practical superconductor development for electrical applications - Argonne National Laboratory quarterly report for the period ending September 30, 2002.

Description: This is a multiyear experimental research program that focuses on improving relevant material properties of high-T{sub c} superconductors (HTSs) and developing fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of the Argonne (ANL) program.
Date: December 2, 2002
Creator: Dorris, S. E.
Partner: UNT Libraries Government Documents Department

Practical superconductor development for electrical power applications - quarterly report for the period ending Dec. 31, 2003.

Description: This is a multiyear experimental research program that focuses on improving relevant material properties of high-critical temperature (Tc) superconductors and developing fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of the Argonne National Laboratory (ANL) program.
Date: March 2, 2004
Creator: Dorris, S. E.
Partner: UNT Libraries Government Documents Department

Practical superconductor development for electrical power applications - quarterly report for the period ending June 30, 2004.

Description: This is a multiyear experimental research program that focuses on improving relevant material properties of high-critical-temperature (Tc) superconductors and developing fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of the Argonne National Laboratory (ANL) program.
Date: September 9, 2004
Creator: Dorris, S. E.
Partner: UNT Libraries Government Documents Department

Practical superconductor development for electrical power applications - Argonne National Laboratory - quarterly report for the period ending June 30, 2001.

Description: This is a multiyear experimental research program focused on improving relevant material properties of high-T{sub c} superconductors (HTSs) and on development of fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of the Argonne (ANL) program.
Date: August 21, 2001
Creator: Dorris, S. E.
Partner: UNT Libraries Government Documents Department

Practical superconductor development for electrical applications - quarterly report for the period ending June 30, 2002.

Description: This is a multiyear experimental research program that focuses on improving relevant material properties of high-T{sub c} superconductors (HTSs) and developing fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of the Argonne National Laboratory (ANL) program. The technical highlights from this quarter are that the capabilities and performance of a new pulsed laser deposition system (PLD2) are described. Using PLD2, a YBa{sub 2}Cu{sub 3}O{sub x} (YBCO) film with critical current density (J{sub c}) of 5.3 MA/cm{sup 2} was prepared on single-crystal SrTiO{sub 3} (STO). Study of a RABiTS{trademark} sample from Oak Ridge National Laboratory showed new effects of magnetic history on grain boundary transport in YBCO. The critical current (I{sub c}) of melt-textured YBCO rings was measured under pulsed current conditions.
Date: September 17, 2002
Creator: Dorris, S. E.
Partner: UNT Libraries Government Documents Department

Practical superconductor development for electrical power applications - quarterly report for the period ending March 31, 2002.

Description: This is a multiyear experimental research program that focuses on improving relevant material properties of high-T{sub c} superconductors (HTSs) and developing fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of the Argonne National Laboratory (ANL) program. Technical Highlights are the capabilities and performance of a new pulsed laser deposition system (PLD2) are described. Using PLD2, a YBa{sub 2}Cu{sub 3}O{sub x} (YBCO) film with critical current density (J{sub c}) of 5.3 MA/cm{sup 2} was prepared on single-crystal SrTiO{sub 3} (STO). Study of a RABiTS{trademark} sample from Oak Ridge National Laboratory showed new effects of magnetic history on grain boundary transport in YBCO. The critical current (I{sub c}) of melt-textured YBCO rings was measured under pulsed current conditions.
Date: May 22, 2002
Creator: Dorris, S. E.
Partner: UNT Libraries Government Documents Department

Development of proton-conducting membranes for separating hydrogen from gas mixtures

Description: Dense ceramic membranes made from mixed protonic/electronic conductors are permeable only to hydrogen, and in principle, provide a simple efficient means of separating hydrogen from gas mixtures. At a time when world demand for hydrogen is growing, such proton- conducting membranes have the potential to significantly alter the economics of hydrogen separation and purification processes and thus improve the economic viability of processes that utilize hydrogen, such as some refinery operations and direct and indirect coal liquefaction. This paper describes a recently initiated program to develop materials and fabrication processes to separate hydrogen with dense ceramic membranes in a non-Galvanic mode of operation (i.e., without electrodes or external power supply).
Date: June 1, 1996
Creator: Dorris, S.E. & Balachandran
Partner: UNT Libraries Government Documents Department

Development of proton-conducting membranes for separating hydrogen from gas mixtures

Description: Thin and dense ceramic membranes fabricated from mixed protonic/electronic conductors can provide a simple, efficient means of separating hydrogen from gas streams and offer an alternative to existing methods of hydrogen recovery. Because mixed electronic/protonic conductors internally transport not only hydrogen (and thus provide the means to separate hydrogen from other gaseous components) but also electrons, hydrogen separation could be achieved in a non-Galvanic mode of operation (i.e., without the need for external electrodes, circuitry, and/or power supply). To be suitable as a hydrogen-permeable membrane, a material must exhibit sufficiently high electronic and protonic conductivities, and these conductivities must be approximately equal to one another to maximize hydrogen permeation through the material. In addition, the material must have sufficient mechanical integrity to withstand normal operating stresses and must be chemically stable under a wide range of gas atmospheres. This talk summarizes results obtained in Argonne`s effort to develop material for use as a hydrogen separation membrane. The transport properties of BaCe{sub 0.95}Y{sub 0.05}O{sub 3{minus}{alpha}} (5%-BCY) and SrCe{sub 0.95}Y{sub 0.05}O{sub 3{minus}{alpha}} (5%-SCY) were characterized by impedance spectroscopy, gas permeation, and open-cell voltage measurements. In this presentation, the authors describe the materials selection, synthesis, characterization, and performance evaluation of mixed-conducting dense ceramic membranes for hydrogen separation applications.
Date: September 1, 1997
Creator: Balachandran, U.; Guan, J.; Dorris, S.E. & Liu, M.
Partner: UNT Libraries Government Documents Department

Development of proton-conducting membranes for hydrogen separation

Description: The objective of this project is to develop dense ceramic membranes that can efficiently and economically separate hydrogen from gaseous mixtures (e.g., syngas, coal gas, etc.). Toward this end, materials with suitable electronic and protonic conductivities will be identified, and methods for fabricating thin, dense ceramic membranes from such materials will be developed. The chemical and mechanical stability of the membranes will be determined to estimate the expected lifetime of the membranes. Scoping-level evaluations will be performed to identify potential applications of proton membrane technology. Areas that will be evaluated include overall market scale, typical site operating scale, process integration opportunities and issues, and alternative-source economics. The literature on mixed electronic/protonic conductors was surveyed to identify suitable candidate materials. SrCe{sub 1{minus}x}M{sub x}O{sub 3{minus}{delta}} and BaCe{sub 1{minus}x}M{sub x}O{sub 3{minus}{delta}} (where M is a fixed-valent dopant such as Ca, Y, Yb, In, Nd, or Gd) were selected for further investigation on the basis of their reported total conductivities and proton transference numbers.
Date: July 1, 1998
Creator: Balachandran, U.; Guan, J. & Dorris, S.E.
Partner: UNT Libraries Government Documents Department

Phase stability domains of (Bi,Pb-2223): Data sources, correlation, and assessment

Description: An assessment of the phase stability of lead-doped Bi-2223, (Bi,Pb)-2223, as a function of temperature and partial pressure of oxygen, p(0{sub 2}), derived from equilibration and electromotive force studies carried out by numerous groups of investigators is presented. The data obtained from this assessment, coupled with additional more recent data from the laboratory, can be used to estimate the stability of this promising high-{Tc} bismuth cuprate system in the temperature range from 650 to 870 C and for oxygen partial pressures ranging from 10{sup {minus}5} to one atm.
Date: December 23, 1999
Creator: Tetenbaum, M.; Maroni, V. A.; Murphy, N. M. & Dorris, S. E.
Partner: UNT Libraries Government Documents Department

Development of mixed-conducting ceramic membrane for hydrogen separation.

Description: The Office of Fossil Energy of the US Department of Energy is formulating ''Vision 21,'' a program aimed at developing technologies for highly efficient power and coproduction plants that discharge almost no pollutants and close the carbon cycle. An integrated gasification combined cycle (IGCC) system is a likely modular component of a Vision 21 coproduction plant. IGCC technology is ideally suited for the coproduction of electricity and high-quality transportation fuel and/or a host of high-value chemicals. As part of the IGCC system, high-temperature membranes for separating hydrogen from coal gasification and other partial-oxidation-product streams are being considered. Thin and dense ceramic membranes fabricated from mixed protonic and electronic conductors provide a simple, efficient means for separating hydrogen from gas streams. Dense mixed-conducting ceramic membranes effect transport via ion- and electron-conducting mechanisms. Because these membranes have no interconnected porosity, selectively for hydrogen is nearly 100%. Hydrogen separation is achieved in a nongalvanic mode, i.e., without the need for electrodes and external power supply to drive the separation. BaCeO{sub 3}-based materials exhibit protonic conductivity that is significantly higher than its electronic conductivity. To enhance the electronic conductivity and increase hydrogen permeation, we have fabricated BaCeO{sub 3}-containing cermet membranes and used them in a nongalvanic mode to separate hydrogen from gas streams containing H{sub 2}, CO, CO{sub 2} and trace amounts of H{sub 2}S. Material selection, fabrication, performance as well as technical/technological challenges of the ceramic membranes for hydrogen separation are discussed in this talk.
Date: August 20, 1999
Creator: Balachandran, U.; Dorris, S. E. & Lee, T. H.
Partner: UNT Libraries Government Documents Department

Current status of dense ceramic membranes for hydrogen separation.

Description: We have developed cermet membranes that nongalvanically separate hydrogen from gas mixtures. The highest measured hydrogen flux was 16.2 cm{sup 3} (STP)/min-cm{sup 2} for an ANL-3a membrane at 900 C. For ANL-3 membranes with thickness of 0.04-0.5 mm, permeation rate is limited by the bulk diffusion of hydrogen through the metal phase. The effect of hydrogen partial pressure on permeation rate confirmed this conclusion and suggested that higher permeation rates may be obtained by decreasing the membrane thickness. Permeation rate in a syngas atmosphere for times up to 190 h showed no degradation in performance, which indicates that ANL-3 may be suitable for long-term, practical hydrogen separation.
Date: February 22, 2002
Creator: Balachandran, U.; Lee, T. H.; Wang, S.; Zhang, G. & Dorris, S. E.
Partner: UNT Libraries Government Documents Department

Dense ceramic membranes for hydrogen separation.

Description: We have developed cermet membranes that nongalvanically separate hydrogen from gas mixtures. The highest measured hydrogen flux was 20.0 cm{sup 3} (STP)/min-cm{sup 2} for an ANL-3a membrane at 900 C. For ANL-3 membranes with thickness of 40-500 {micro}m, hydrogen permeation is limited by the bulk diffusion of hydrogen through the metal phase. The effect of hydrogen partial pressure on permeation rate confirmed this conclusion, suggesting that higher permeation rates may be obtained by decreasing the membrane thickness. Permeation rate in a syngas atmosphere for times up to 190 h showed no degradation in performance, which indicates that ANL-3 membranes may be suitable for long-term, practical hydrogen separation.
Date: May 7, 2002
Creator: Balachandran, U.; Lee, T. H.; Wang, S.; Zhang, G. & Dorris, S. E.
Partner: UNT Libraries Government Documents Department

Hydrogen production by high-temperature water splitting using mixed oxygen ion-electron conducting membranes.

Description: Hydrogen production from water splitting at high temperatures has been studied with novel mixed oxygen ion-electron conducting cermet membranes. Hydrogen production rates were investigated as a function of temperature, water partial pressure, membrane thickness, and oxygen chemical potential gradient across the membranes. The hydrogen production rate increased with both increasing moisture concentration and oxygen chemical potential gradient across the membranes. A maximum hydrogen production rate of 4.4 cm{sup 3}/min-cm{sup 2} (STP) was obtained with a 0.10-mm-thick membrane at 900 C in a gas containing 50 vol.% water vapor in the sweep side. Hydrogen production rate also increased with decreasing membrane thickness, but surface kinetics play an important role as membrane thickness decreases.
Date: April 24, 2002
Creator: Lee, T. H.; Wang, S.; Dorris, S. E. & Balachandran, U.
Partner: UNT Libraries Government Documents Department

The effect of processing parameters during heat treatment of bulk high- Tc superconductors

Description: Plastic extrusion is a promising method for producing the long lengths of high-{Tc} superconductor that will be necessary to meet many potential applications. A crucial phase of the extrusion method is removal of organic constituents. Incomplete removal can leave residual carbon at grain boundaries, which can adversely affect the superconducting properties, whereas excessively rapid removal of the organics can cause the extruded superconductor to disintegrate completely. In this paper, we analyze the effects of the following aspects of organics removal, as they apply to the firing of extruded YBa{sub 2}Cu{sub 3}O{sub x} coils: (1) total pressure in the furnace, (2) oxygen flow, (3) heat conduction, and (4) diffusion of volatile components during removal of organics.
Date: April 1, 1991
Creator: Cha, Y.S.; Dorris, S.E.; Hull, J.R. & Poeppel, R.B.
Partner: UNT Libraries Government Documents Department

The effect of processing parameters during heat treatment of bulk high-{Tc} superconductors

Description: Plastic extrusion is a promising method for producing the long lengths of high-{Tc} superconductor that will be necessary to meet many potential applications. A crucial phase of the extrusion method is removal of organic constituents. Incomplete removal can leave residual carbon at grain boundaries, which can adversely affect the superconducting properties, whereas excessively rapid removal of the organics can cause the extruded superconductor to disintegrate completely. In this paper, we analyze the effects of the following aspects of organics removal, as they apply to the firing of extruded YBa{sub 2}Cu{sub 3}O{sub x} coils: (1) total pressure in the furnace, (2) oxygen flow, (3) heat conduction, and (4) diffusion of volatile components during removal of organics.
Date: April 1, 1991
Creator: Cha, Y. S.; Dorris, S. E.; Hull, J. R. & Poeppel, R. B.
Partner: UNT Libraries Government Documents Department

Sealant research for solid oxide fuel cells

Description: The objective of this work is to develop sealing materials for solid oxide fuels cells (SOFCs). A suitable sealant must form strong, dense bonds with SOFC components, be chemically and mechanically compatible with the components, be stable at 1000{sup degrees}C in the operating environment of the SOFC (H{sup 2} and H{sup 2}O on the anode side, O{sub 2} on the cathode side), and must be nonconductive.
Date: June 1, 1992
Creator: Dorris, S. E.; Bloom, I.; Hash, M. C. & Krumpelt, M.
Partner: UNT Libraries Government Documents Department

Hydrogen production by water dissociation using ceramic membranes. Annual report for FY 2007.

Description: The objective of this project is to develop dense ceramic membranes that, without using an external power supply or circuitry, can produce hydrogen via coal/coal gas-assisted water dissociation. This project grew out of an effort to develop a dense ceramic membrane for separating hydrogen from gas mixtures such as those generated during coal gasification, methane partial oxidation, and water-gas shift reactions [1]. That effort led to the development of various cermet (i.e., ceramic/metal composite) membranes that enable hydrogen to be produced by two methods. In one method, a hydrogen transport membrane (HTM) selectively removes hydrogen from a gas mixture by transporting it through either a mixed protonic/electronic conductor or a hydrogen transport metal. In the other method, an oxygen transport membrane (OTM) generates hydrogen mixed with steam by removing oxygen that is generated through water splitting [1, 2]. This project focuses on the development of OTMs that efficiently produce hydrogen via the dissociation of water. Supercritical boilers offer very high-pressure steam that can be decomposed to provide pure hydrogen by means of OTMs. Oxygen resulting from the dissociation of steam can be used for coal gasification, enriched combustion, or synthesis gas production. Hydrogen and sequestration-ready CO{sub 2} can be produced from coal and steam by using the membrane being developed in this project. Although hydrogen can also be generated by high-temperature steam electrolysis, producing hydrogen by water splitting with a mixed-conducting membrane requires no electric power or electrical circuitry.
Date: March 4, 2008
Creator: Balachandran, U.; Chen, L.; Dorris, S. E.; Emerson, J. E.; Lee, T. H.; Park, C. Y. et al.
Partner: UNT Libraries Government Documents Department

Hydrogen separation membranes - annual report for FY 2007.

Description: The objective of this work is to develop dense ceramic membranes for separating hydrogen from other gaseous components in a nongalvanic mode, i.e., without using an external power supply or electrical circuitry.
Date: January 31, 2008
Creator: Chen, L.; Dorris, S. E.; Emerson, J. E.; Lee, T. H.; Park, C. Y.; Picciolo, J. J. et al.
Partner: UNT Libraries Government Documents Department

Hydrogen production by water dissociation using ceramic membranes - annual report for FY 2010.

Description: The objective of this project is to develop dense ceramic membranes that can produce hydrogen via coal/coal gas-assisted water dissociation without using an external power supply or circuitry. This project grew from an effort to develop a dense ceramic membrane for separating hydrogen from gas mixtures such as those generated during coal gasification, methane partial oxidation, and water-gas shift reactions. That effort led to the development of various cermet (i.e., ceramic/metal composite) membranes that enable hydrogen production by two methods. In one method, a hydrogen transport membrane (HTM) selectively removes hydrogen from a gas mixture by transporting it through either a mixed protonic/electronic conductor or a hydrogen transport metal. In the other method, an oxygen transport membrane (OTM) generates hydrogen mixed with steam by removing oxygen that is generated through water splitting. This project focuses on the development of OTMs that efficiently produce hydrogen via the dissociation of water. Supercritical boilers offer very high-pressure steam that can be decomposed to provide pure hydrogen using OTMs. Oxygen resulting from the dissociation of steam can be used for coal gasification, enriched combustion, or synthesis gas production. Hydrogen and sequestration-ready CO{sub 2} can be produced from coal and steam by using the membrane being developed in this project. Although hydrogen can also be generated by high-temperature steam electrolysis, producing hydrogen by water splitting with a mixed-conducting membrane requires no electric power or electrical circuitry.
Date: March 14, 2011
Creator: Balachandran, U.; Dorris, S. E.; Emerson, J. E.; Lee, T. H.; Lu, Y.; Park, C. Y. et al.
Partner: UNT Libraries Government Documents Department