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Linking Initial Microstructure to ORR Related Property Degradation in SOFC Cathode: A Phase Field Simulation
Creators: Lei, Y. [National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV (United States). Albany Research Center (ARC)] (ORCID:0000000202001491); Cheng, T. -L. [National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV (United States). Albany Research Center (ARC); AECOM, Albany, OR (United States)]; Wen, Y. H. [National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV (United States). Albany Research Center (ARC)]
Date: 07/05/2017
Description: Microstructure evolution driven by thermal coarsening is an important factor for the loss of oxygen reduction reaction rates in SOFC cathode. In this work, the effect of an initial microstructure on the microstructure evolution in SOFC cathode is investigated using a recently developed phase field model. Specifically, we tune the phase fraction, the average grain size, the standard deviation of the grain size and the grain shape in the initial microstructure, and explore their effect on the evolution of the grain size, the density of triple phase boundary, the specific surface area and the effective conductivity in LSM-YSZ cathodes. It is found that the degradation rate of TPB density and SSA of LSM is lower with less LSM phase fraction (with constant porosity assumed) and greater average grain size, while the degradation rate of effective conductivity can also be tuned by adjusting the standard deviation of grain size distribution and grain aspect ratio. The implication of this study on the designing of an optimal initial microstructure of SOFC cathodes is discussed.


Pre-treating water with non-thermal plasma
Creators: Cho, Young I.; Fridman, Alexander; Rabinovich, Alexander; Cho, Daniel J.
Date: 07/04/2017
Description: The present invention consists of a method of pre-treatment of adulterated water for distillation, including adulterated water produced during hydraulic fracturing ("fracking") of shale rock during natural gas drilling. In particular, the invention is directed to a method of treating adulterated water, said adulterated water having an initial level of bicarbonate ion in a range of about 250 ppm to about 5000 ppm and an initial level of calcium ion in a range of about 500 ppm to about 50,000 ppm, said method comprising contacting the adulterated water with a non-thermal arc discharge plasma to produce plasma treated water having a level of bicarbonate ion of less than about 100 ppm. Optionally, the plasma treated water may be further distilled.


Spatio-temporal distribution of Oklahoma earthquakes: Exploring relationships using a nearest-neighbor approach: Nearest-neighbor analysis of Oklahoma
Creators: Vasylkivska, Veronika S. [National Energy Technology Laboratory, Albany OR USA; Oak Ridge Institute for Science and Education, Oak Ridge TN USA] (ORCID:0000000211481271); Huerta, Nicolas J. [National Energy Technology Laboratory, Albany OR USA]
Date: 06/24/2017
Description:


Mechanistic insights into the oxidation behavior of Ni alloys in high-temperature CO2
Creators: Oleksak, Richard P.; Baltrus, John P.; Nakano, Jinichiro; Nakano, Anna; Holcomb, Gordon R.; Dogan, Omer N.
Date: 06/01/2017
Description: We present results of a Ni superalloy oxidized for short times in high purity CO2 and similarly in Ar containing ≤ 1 ppb O2. A detailed analysis of the oxidized surfaces reveals striking similarities for the two exposure environments, suggesting O2 impurities control the oxidation process in high-temperature CO2. Selective oxidation results in Cr-rich oxide layers grown by 2 outward diffusion, while Cr vacancies left in the metal contribute to significant void formation at the oxide/metal interface. Unlike for most of the alloy surface, the oxidation behavior of secondary phase metal carbides is considerably different in the two environments.


Over-voltage protection system and method
Creators: Chi, Song; Dong, Dong; Lai, Rixin
Date: 05/02/2017
Description: An over-voltage protection system includes an electronic valve connected across two terminals of a circuit and an over-voltage detection circuit connected across one of the plurality of semiconductor devices for detecting an over-voltage across the circuit. The electronic valve includes a plurality of semiconductor devices connected in series. The over-voltage detection circuit includes a voltage divider circuit connected to a break-over diode in a way to provide a representative low voltage to the break-over diode and an optocoupler configured to receive a current from the break-over diode when the representative low voltage exceeds a threshold voltage of the break-over diode indicating an over-voltage condition. The representative low voltage provided to the break-over diode represents a voltage across the one semiconductor device. A plurality of self-powered gate drive circuits are connected to the plurality of semiconductor devices, wherein the plurality of self-powered gate drive circuits receive over-voltage triggering pulses from the optocoupler during the over-voltage condition and switch on the plurality of semiconductor devices to bypass the circuit.


Mechanical membrane for the separation of a paramagnetic constituent from a fluid
Creators: Maurice, David
Date: 05/02/2017
Description: The disclosure provides an apparatus and method for the separation of a paramagnetic component from a mixture using a mechanical membrane apparatus. The mechanical membrane comprises a supporting material having a plurality of pores where each pore is surrounded by a plurality of magnetic regions. The magnetic regions augment a magnetic field on one side of the supporting material while mitigating the field to near zero on the opposite side. In operation, a flow of fluid such as air comprising a paramagnetic component such as O.sub.2 is directed toward the mechanical membrane, and the paramagnetic component is typically attracted toward a magnetic field surrounding a pore while dimagnetic components such as N.sub.2 are generally repelled. As some portion of the fluid passes through the plurality of magnetic apertures to the opposite side of the mechanical membrane, the mechanical membrane generates a fluid enriched in the paramagnetic component. Alternately, the magnetic field may act to repel the paramagnetic component while diamagnetic components such as N.sub.2 are generally unaffected and pass to the opposite side of the mechanical membrane.


US-UK Collaboration on Fossil Energy Advanced Materials: Task 2—Materials for Advanced Boiler and Oxy-combustion Systems(NETL-US)
Creators: Holcomb, Gordon; Tylczak, Joseph; Carney, Casey
Date: 04/19/2017
Description:


NETL CO2 Storage prospeCtive Resource Estimation Excel aNalysis (CO2-SCREEN) User's Manual
Creators: Sanguinito, Sean M. [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States)]; Goodman, Angela [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States)]; Levine, Jonathan [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States)]
Date: 04/03/2017
Description: This user’s manual guides the use of the National Energy Technology Laboratory’s (NETL) CO2 Storage prospeCtive Resource Estimation Excel aNalysis (CO2-SCREEN) tool, which was developed to aid users screening saline formations for prospective CO2 storage resources. CO2- SCREEN applies U.S. Department of Energy (DOE) methods and equations for estimating prospective CO2 storage resources for saline formations. CO2-SCREEN was developed to be substantive and user-friendly. It also provides a consistent method for calculating prospective CO2 storage resources that allows for consistent comparison of results between different research efforts, such as the Regional Carbon Sequestration Partnerships (RCSP). CO2-SCREEN consists of an Excel spreadsheet containing geologic inputs and outputs, linked to a GoldSim Player model that calculates prospective CO2 storage resources via Monte Carlo simulation.


Method of CO and/or CO.sub.2 hydrogenation to higher hydrocarbons using doped mixed-metal oxides
Creators: Shekhawat, Dushyant; Berry, David A.; Haynes, Daniel J.; Abdelsayed, Victor; Smith, Mark W.; Spivey, James J.
Date: 03/21/2017
Description: A method of hydrogenation utilizing a reactant gas mixture comprising a carbon oxide and a hydrogen agent, and a hydrogenation catalyst comprising a mixed-metal oxide containing metal sites supported and/or incorporated into the lattice. The mixed-metal oxide comprises a pyrochlore, a brownmillerite, or mixtures thereof doped at the A-site or the B-site. The metal site may comprise a deposited metal, where the deposited metal is a transition metal, an alkali metal, an alkaline earth metal, or mixtures thereof. Contact between the carbon oxide, hydrogen agent, and hydrogenation catalyst under appropriate conditions of temperature, pressure and gas flow rate generate a hydrogenation reaction and produce a hydrogenated product made up of carbon from the carbon oxide and some portion of the hydrogen agent. The carbon oxide may be CO, CO.sub.2, or mixtures thereof and the hydrogen agent may be H.sub.2. In a particular embodiment, the hydrogenated product comprises olefins, paraffins, or mixtures thereof.


Chromia refractory brick with carbon treatment
Creators: Bennett, James P.; Kwong, Kyei-Sing
Date: 03/21/2017
Description: The disclosure provides a refractory brick system comprising a chromia refractory brick for operation in the slagging environment of an air-cooled gasifier. The chromia refractory brick comprises a ceramically-bonded porous chromia refractory having a porosity greater than 9% and having carbon deposits residing within the pores. The brick may be further comprised of Al.sub.2O.sub.3. The air-cooled gasifier generates a liquefied slag in contact with the refractory brick and generally operates at temperatures between 1250.degree. C. and 1575.degree. C. and pressures between 300 psi to 1000 psi, with oxygen partial pressures generally between 10.sup.-4 and 10.sup.-10 atm. The refractory brick performs without substantial chromium carbide or chromium metal formation in the low oxygen partial pressure environment. The inclusion of carbon without chromium carbide formation provides for significant mitigation of slag penetration and significantly reduced refractory wear.


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