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Articles 1681 - 1710 of 3295
Full-Text Articles in Engineering
Querie: Collaborative Database Exploration, Magdalini Eirinaki, Suju Abraham, Neoklis Polyzotis, Naushin Shaikh
Querie: Collaborative Database Exploration, Magdalini Eirinaki, Suju Abraham, Neoklis Polyzotis, Naushin Shaikh
Faculty Publications
No abstract provided.
A Position Analysis Of Coupled Spherical Mechanisms In Action Origami, Landen A. Bowen, L. A. Baxter, Spencer P. Magleby, Larry L. Howell
A Position Analysis Of Coupled Spherical Mechanisms In Action Origami, Landen A. Bowen, L. A. Baxter, Spencer P. Magleby, Larry L. Howell
Faculty Publications
Origami has been previously utilized in design to create deployable systems. Action origami, origami designed to move, has the ability to deploy to a larger state and have motion in the deployed state. The majority of action origami achieves motion through coupled systems of spherical mechanisms. An origami vertex, the point at which folds converge, is shown to be equivalent to a spherical change-point mechanism. A position analysis of an origami vertex is presented, resulting in a relationship between input and output angles as well as the path of the coupler link. A method for analyzing coupled systems of repeated …
Initial Capabilities Documents: A 10-Year Retrospective Of Tools, Methodologies, And Best Practices, Bryan D. Main, Michael P. Kretser, Joshua Shearer, Darrin A. Ladd
Initial Capabilities Documents: A 10-Year Retrospective Of Tools, Methodologies, And Best Practices, Bryan D. Main, Michael P. Kretser, Joshua Shearer, Darrin A. Ladd
Faculty Publications
The Joint Capabilities Integration and Development System (JCIDS) is 10 years old and ripe for review. A central output document of the JCIDS process is an Initial Capabilities Document (ICD) used by the Department of Defense to define gaps in a functional capability area and define new capabilities required. The research team analyzed 10 years of ICDs to identify methods and trends. The team found that several methodologies were favored and a convergence emerged in format and necessary content. Additionally, potential shortfalls in current best practices of interest to implementers and decision makers are identified. Guidelines and best practices are …
Are Undergraduate Gpa And General Gre Percentiles Valid Predictors Of Student Performance In An Engineering Graduate Program?, Larry L. Howell, Carl D. Sorenson, Matthew R. Jones
Are Undergraduate Gpa And General Gre Percentiles Valid Predictors Of Student Performance In An Engineering Graduate Program?, Larry L. Howell, Carl D. Sorenson, Matthew R. Jones
Faculty Publications
While both subjective measures and quantitative metrics play an important role in admissions decisions, quantitative metrics are amenable to critical analysis using the tools of academic analytics. The hypotheses that motivated this study are: 1. Can an applicant’s undergraduate grade point average (UGPA) and scores on the Graduate Records Examinations (GRE) be used to accurately predict the performance of the applicant in a graduate mechanical engineering program? 2. Is a single construct based on these quantitative predictive metrics a valuable tool in efficiently making admissions decisions? This study analyzed the relationship between quantitative predictive metrics, available at the time of …
Large Research Center Education And Outreach: Lessons From 5 Years Of Distributed Collaborative Design, Development And Implementation, Sean Brophy, Thalia Anagnos
Large Research Center Education And Outreach: Lessons From 5 Years Of Distributed Collaborative Design, Development And Implementation, Sean Brophy, Thalia Anagnos
Faculty Publications
Paper from the 121st ASEE Annual Conference, Indianapolis. The George E. Brown, Jr. Network for Earthquake Engineering Summation (NEES) completes its tenth year of operation in September 2014. The NEES Center consists of a network of 14 large-scale experimental laboratories that collaborate and share resources in support of research to inform civil engineering practice and reduce losses from future earthquakes. Since the development of the center in 2003, the education, outreach and training (EOT) program has grown from a federation of local outreach activities to an integrated network of “specialists” working together to obtain significant impact towards defined education goals. …
Phonon Confinement Using Spirally Designed Elastic Resonators In Discrete Continuum, Sourav Banerjee, Raiz U. Ahmed
Phonon Confinement Using Spirally Designed Elastic Resonators In Discrete Continuum, Sourav Banerjee, Raiz U. Ahmed
Faculty Publications
Periodic and chiral orientation of microstructures, here we call phononic crystals, have extraordinary capabilities to facilitate the innovative design of new generation metamaterials. Periodic arrangements of phononic crystals are capable of opening portals of non-passing, non-dispersive mechanical waves. Defying conventional design of regular periodicity, in this paper spirally periodic but chiral orientation of resonators are envisioned. Dynamics of the spirally connected resonators and the acoustic wave propagation through the spirally connected multiple local resonators are studied using fundamental physics. In present study the spiral systems with local resonators are assumed to be discrete media immersed in fluid. In this paper …
Uncertainty Quantification Driven Predictive Multi-Scale Model For Synthesis Of Mycotoxins, Sourav Banerjee, Gabriel A. Terejanu, Anindya Chanda
Uncertainty Quantification Driven Predictive Multi-Scale Model For Synthesis Of Mycotoxins, Sourav Banerjee, Gabriel A. Terejanu, Anindya Chanda
Faculty Publications
Many toxic molds synthesize and release an array of poisons, termed mycotoxins that have an enormous impact on human health, agriculture and economy [1]. These molds contaminate our buildings, indoor air and crops, cause life threatening human and animal diseases and reduce agricultural output [2]. In order to design appropriate approaches to minimize the detrimental effects of these fungi, it is essential to develop diagnostic methodologies that can rapidly and accurately determine based on fungal strains and their growth patterns, the extent of mycotoxin mediated damage caused to the environment.Here we developed a novel multi-scale predictive mathematical model that could …
Effect Of Z1/2, Eh5, And Ci1 Deep Defects On The Performance Of N-Type 4h-Sic Epitaxial Layers Schottky Detectors: Alpha Spectroscopy And Deep Level Transient Spectroscopy Studies, M. A. Mannan, S. K. Chaudhuri, K. V. Nguyen, K. C. Mandal
Effect Of Z1/2, Eh5, And Ci1 Deep Defects On The Performance Of N-Type 4h-Sic Epitaxial Layers Schottky Detectors: Alpha Spectroscopy And Deep Level Transient Spectroscopy Studies, M. A. Mannan, S. K. Chaudhuri, K. V. Nguyen, K. C. Mandal
Faculty Publications
No abstract provided.
Comparison Of One-Dimensional Turbulence And Direct Numerical Simulations Of Soot Formation And Transport In A Nonpremixed Ethylene Jet Flame, David O. Lignell, Garrison C. Fredline, Adam D. Lewis
Comparison Of One-Dimensional Turbulence And Direct Numerical Simulations Of Soot Formation And Transport In A Nonpremixed Ethylene Jet Flame, David O. Lignell, Garrison C. Fredline, Adam D. Lewis
Faculty Publications
Accurate models of soot formation in turbulent flames are important for correctly predicting and simulating flames and fires. Modeling soot formation and transport is challenging due to the complex chemical formation processes, and differential diffusion of soot relative to a flame. Direct numerical simulations (DNS) have highlighted the importance of such transport on soot concentrations, however DNS is computationally expensive. The one-dimensional turbulence (ODT) model is able resolve a full range of length and timescales and solves the evolution of diffusive and reactive scalars in the natural physical coordinate. We present results of soot formation in ODT and compare the …
Broadband, Non-Destructive Characterisation Of Pec-Backed Materials Using A Dual-Ridged-Waveguide Probe, Milo W. Hyde Iv, Michael J. Havrilla
Broadband, Non-Destructive Characterisation Of Pec-Backed Materials Using A Dual-Ridged-Waveguide Probe, Milo W. Hyde Iv, Michael J. Havrilla
Faculty Publications
A new probe which utilises a dual-ridged waveguide to provide broadband, non-destructive (ND) material characterisation measurements of a perfect electric conductor (PEC)-backed material is introduced. The new probe possesses a bandwidth similar to existing coaxial probes and is structurally robust like rectangular waveguide probes. The combinations of these two qualities make it especially attractive for ND inspection/evaluation applications in the field. The theoretical development of the dual-ridged-waveguide probe is discussed. A magnetic field integral equation is derived by applying Love’s equivalence theorem and enforcing the continuity of transverse fields at the dual-ridged-waveguide aperture. The magnetic field integral equation is then …
Redox Stable Anodes For Solid Oxide Fuel Cells, Guoliang Xiao, Fanglin Chen
Redox Stable Anodes For Solid Oxide Fuel Cells, Guoliang Xiao, Fanglin Chen
Faculty Publications
Solid oxide fuel cells (SOFCs) can convert chemical energy from the fuel directly to electrical energy with high efficiency and fuel flexibility. Ni-based cermets have been the most widely adopted anode for SOFCs. However, the conventional Ni-based anode has low tolerance to sulfur-contamination, is vulnerable to deactivation by carbon build-up (coking) from direct oxidation of hydrocarbon fuels, and suffers volume instability upon redox cycling. Among these limitations, the redox instability of the anode is particularly important and has been intensively studied since the SOFC anode may experience redox cycling during fuel cell operations even with the ideal pure hydrogen as …
Simulation And Analysis Of Inhomogeneous Degradation In Large Format Limn2O4/ Carbon Cells, Yiling Dai, Long Cai, Ralph E. White
Simulation And Analysis Of Inhomogeneous Degradation In Large Format Limn2O4/ Carbon Cells, Yiling Dai, Long Cai, Ralph E. White
Faculty Publications
Degradation phenomena are not distributed uniformly in a large-format cell. To better understand the inhomogeneous degradation in large-format cells, a two-dimensional model was developed for a LiMn2O4 (LMO)/Carbon cell. The model includes both the non-uniform porous electrode properties and the electrode mismatch. The simulation results show that when the anode edge is extended over the cathode edge, the LMO particles near the edge suffer larger potential difference, larger charge/discharge depth, and higher insertion-induced stress. Therefore, the predicted loss of LMO is more pronounced near the edge as has been seen experimentally. The influence of different design adjustable …
Quaternion Based Attitude Error For A Tailsitter In Hover Flight, Timothy Mclain, Matthew E. Argyle, Jason M. Beach, Randall W. Beard, Stephen Morris
Quaternion Based Attitude Error For A Tailsitter In Hover Flight, Timothy Mclain, Matthew E. Argyle, Jason M. Beach, Randall W. Beard, Stephen Morris
Faculty Publications
The tailsitter is a promising airframe that can take off and land on its tail and transition to level flight. While this ability provides vertical takeoff and landing capabilities with no additional moving parts, it introduces interesting control challenges. In this paper, we look at the attitude control system of a tailsitter in hover flight and show that the behaviour of the aircraft relies on the method used to compute the attitude error. We investigate three different methods of computing the attitude error, quaternion feedback, resolved tilt twist, and the resolved Euler angles, and compare them through simulated hover flight.
Tailsitter Heading Estimation Using A Magnetometer, Timothy Mclain, Jason M. Beach, Matthew E. Argyle, Randall W. Beard, Stephen Morris
Tailsitter Heading Estimation Using A Magnetometer, Timothy Mclain, Jason M. Beach, Matthew E. Argyle, Randall W. Beard, Stephen Morris
Faculty Publications
The tailsitter aircraft merges the endurance and speed of fixed-wing aircraft with the flexibility and VTOL abilities of rotorcraft. Typical control and estimation schemes make assumptions about the maximum attitude an aircraft will experience that are not valid for tailsitters. This paper discusses the limitations of a typical EKF magnetometer measurement update that uses Euler angles. It is shown how to use a second set of Euler angles to avoid gimbal lock. A method is given that bypasses the use of Euler angles altogether and directly uses the quaternion to determine heading error and update the attitude estimate. This method …
Analysis Of The Conduction-Radiation Problem In Absorbing, Emitting, Non-Gray Planar Media Using An Exact Method, Travis J. Moore, Matthew R. Jones
Analysis Of The Conduction-Radiation Problem In Absorbing, Emitting, Non-Gray Planar Media Using An Exact Method, Travis J. Moore, Matthew R. Jones
Faculty Publications
Systems in which both conduction and radiation are the dominant modes of heat transfer are important in many engineering applications and various numerical methods exist to analyze such systems. An exact solution to the conduction–radiation problem in a one-dimensional, planar, absorbing, emitting, non-gray medium is presented. The method uses an integrating factor to solve the radiative transfer equation and variation of parameters is used to solve the energy equation. The model is verified by comparing the temperature profiles calculated from this work to those found using numerical methods for both gray and non-gray cases.
New Advances In Post-Installed Subsea Monitoring Systems For Structural And Flow Assurance Evaluation, Reza Asgharzadeh Shishavan, David Brower, John Hedengren, Alexis Brower
New Advances In Post-Installed Subsea Monitoring Systems For Structural And Flow Assurance Evaluation, Reza Asgharzadeh Shishavan, David Brower, John Hedengren, Alexis Brower
Faculty Publications
An overview of fiber optic sensors for temperature, pressure, strain, and fatigue of subsea structures is provided. Current progress details efforts to ensure proper installation and bonding to existing risers, flow-lines, mooring lines, trees, and other structures in actual subsea environments. Developments include clamp prototypes, bonding techniques, long-term fatigue analysis, sensor calibration, and temperature compensation. Fiber optic technology in subsea monitoring began over 20 years ago by migrating expertise from decommissioning of rocket motors. The first installations were on new installations of subsea pipelines, production risers, and drilling risers to measure strain and vibration for fatigue life monitoring. Of particular …
Towards The Development Of The Observability-In-Depth Safety Principle In The Nuclear Industry, Francesca Favaro, Joseph Saleh
Towards The Development Of The Observability-In-Depth Safety Principle In The Nuclear Industry, Francesca Favaro, Joseph Saleh
Faculty Publications
No abstract provided.
Automatic Evaluation Of Multidisciplinary Derivatives Using A Graph-Based Problem Formulation In Openmdao, Justin Gray, Tristan Hearn, Kenneth Moore, John Hwang, Joaquim Martins, Andrew Ning
Automatic Evaluation Of Multidisciplinary Derivatives Using A Graph-Based Problem Formulation In Openmdao, Justin Gray, Tristan Hearn, Kenneth Moore, John Hwang, Joaquim Martins, Andrew Ning
Faculty Publications
The optimization of multidisciplinary systems with respect to large numbers of design variables is best pursued using a gradient-based optimization together with a method that efficiently evaluates coupled derivatives, such as the coupled adjoint method. However, implementing such a method in a problem with more than a few disciplines is time consuming and error prone. To address this issue, we develop an automated procedure for assembling and solving the coupled derivative equations that takes into account the disciplinary couplings using the interdisciplinary dependency graph of the problem. The coupled derivatives can be computed completely analytically, if analytic derivatives are available …
Understanding The Benefits And Limitations Of Increasing Maximum Rotor Tip Speed For Utility-Scale Wind Turbines, Andrew Ning
Understanding The Benefits And Limitations Of Increasing Maximum Rotor Tip Speed For Utility-Scale Wind Turbines, Andrew Ning
Faculty Publications
For utility-scale wind turbines, the maximum rotor rotation speed is generally constrained by noise considerations. Innovations in acoustics and/or siting in remote locations may enable future wind turbine designs to operate with higher tip speeds. Wind turbines designed to take advantage of higher tip speeds are expected to be able to capture more energy and utilize lighter drivetrains because of their decreased maximum torque loads. However, the magnitude of the potential cost savings is unclear, and the potential trade-offs with rotor and tower sizing are not well understood. A multidisciplinary, system-level framework was developed to facilitate wind turbine and wind …
Copper Doping Of Zno Crystals By Transmutation Of 64Zn To 65Cu: An Electron Paramagnetic Resonance And Gamma Spectroscopy Study, Matthew C. Recker, John W. Mcclory, Maurio S. Holston, Eric M. Golden, Nancy C. Giles, Larry E. Halliburton
Copper Doping Of Zno Crystals By Transmutation Of 64Zn To 65Cu: An Electron Paramagnetic Resonance And Gamma Spectroscopy Study, Matthew C. Recker, John W. Mcclory, Maurio S. Holston, Eric M. Golden, Nancy C. Giles, Larry E. Halliburton
Faculty Publications
Transmutation of 64Zn to 65Cu has been observed in a ZnO crystal irradiated with neutrons. The crystal was characterized with electron paramagnetic resonance (EPR) before and after the irradiation and with gamma spectroscopy after the irradiation. Major features in the gamma spectrum of the neutron-irradiated crystal included the primary 1115.5 keV gamma ray from the 65Zn decay and the positron annihilation peak at 511 keV. Their presence confirmed the successful transmutation of 64Zn nuclei to 65Cu. Additional direct evidence for transmutation was obtained from the EPR of Cu2+ ions (where 63Cu and 65 …
Probing The Roles Of Polymeric Separators In Lithium-Ion Battery Capacity Fade At Elevated Temperatures, Jianchao Chen, Yongda Yan, Tao Sun, Yue Qi, Xiaodong Li
Probing The Roles Of Polymeric Separators In Lithium-Ion Battery Capacity Fade At Elevated Temperatures, Jianchao Chen, Yongda Yan, Tao Sun, Yue Qi, Xiaodong Li
Faculty Publications
The high temperature mechanical property of separators is very important for safety of lithium-ion batteries. However, the mechanical integrity of polymeric separators in lithium-ion batteries at elevated temperatures is still not well characterized. In this paper, the temperature dependent micro-scale morphology change of PP (polypropylene)-PE (polyethylene)-PP sandwiched separators (Celgard 2325) was studied by in-situ high temperature surface imaging using an atomic force microscope (AFM) coupled with power spectral density (PSD) analysis and digital image correlation (DIC) technique. Both PSD and DIC analysis results show that the PP phase significantly closes its pores by means of dilation of the nanofibrils surrounding …
Averaging Improves Strain Images Of The Biceps Brachii Using Quasi-Static Ultrasound Elastography, Matthew Leineweber, J Westborn, A Cochran, Y Gao, J Choi
Averaging Improves Strain Images Of The Biceps Brachii Using Quasi-Static Ultrasound Elastography, Matthew Leineweber, J Westborn, A Cochran, Y Gao, J Choi
Faculty Publications
OBJECTIVE:Quasi-static ultrasound elastography is a technique for measuring tissue deformation (strain) under externally applied loading and can be used to identify the presence of abnormalities. The objective of this study was to demonstrate the efficacy of averaging strain images from repeated compression cycles in mitigating user-induced error using quasi-static ultrasound elastography.METHODS:Freehand compressions were performed with an ultrasound transducer on the biceps brachii of nine participants (five males and four females), as well as with a custom automated compression system. Sets of strain images from the freehand techniques were averaged to create single representative images and compared against strain images from …
The Odijk Regime In Slits, Douglas R. Tree, Wesley F. Reinhart, Kevin D. Dorfman
The Odijk Regime In Slits, Douglas R. Tree, Wesley F. Reinhart, Kevin D. Dorfman
Faculty Publications
De Gennes’ blob theory has been remarkably successful at describing weakly confined polymers in both slits and channels, and comparable results surround Odijk’s theory of deflection segments for strongly confined wormlike polymers in nanochannels. However, given the success of Odijk’s theory in channels, it is remarkable that there is no comprehensive theory for the simple case of a wormlike polymer strongly confined between two parallel plates. We propose such a theory by drawing inspiration from the existing literature on ideal wormlike chains in slits and Daoud and de Gennes’ idea of mapping a slit-confined chain to a two-dimensional chain. We …
A Novel Intermediate-Temperature All Ceramic Iron–Air Redox Battery: The Effect Of Current Density And Cycle Duration, Xuan Zhao, Xue Li, Yunhui Gong, Nansheng Xu, Kevin Huang
A Novel Intermediate-Temperature All Ceramic Iron–Air Redox Battery: The Effect Of Current Density And Cycle Duration, Xuan Zhao, Xue Li, Yunhui Gong, Nansheng Xu, Kevin Huang
Faculty Publications
We here report the energy storage characteristics of a new all ceramic iron–air redox battery comprising of a reversible solid oxide fuel cell as the charger/discharger and a Fe–FeOx redox couple as the chemical storage bed. The effects of current density and cycle duration on specific energy and round trip efficiency of the new battery have been systematically studied at 650°C and 550°C. The results explicitly show that current density is the most influential variable on the performance, signifying the importance of improving electrochemical performance of the reversible solid oxide fuel cell.
Defect Levels In Cu₂Znsn(Sₓse₁₋ₓ)₄ Solar Cells Probed By Current-Mode Deep Level Transient Spectroscopy, S. Das, S. K. Chaudhuri, R. N. Bhattacharya, K. C. Mandal
Defect Levels In Cu₂Znsn(Sₓse₁₋ₓ)₄ Solar Cells Probed By Current-Mode Deep Level Transient Spectroscopy, S. Das, S. K. Chaudhuri, R. N. Bhattacharya, K. C. Mandal
Faculty Publications
No abstract provided.
Characterization Of 3d Interconnected Microstructural Network In Mixed Ionic And Electronic Conducting Ceramic Composites, William M. Harris, Kyle S. Brinkman, Ye Lin, Dong Su, Alex P. Cocco, Arata Nakajo, Matthew B. Degostin, Yu-Chen Karen Chen-Wiegart, Jun Wang, Fanglin Chen, Yong S. Chu, Wilson K. S. Chiu
Characterization Of 3d Interconnected Microstructural Network In Mixed Ionic And Electronic Conducting Ceramic Composites, William M. Harris, Kyle S. Brinkman, Ye Lin, Dong Su, Alex P. Cocco, Arata Nakajo, Matthew B. Degostin, Yu-Chen Karen Chen-Wiegart, Jun Wang, Fanglin Chen, Yong S. Chu, Wilson K. S. Chiu
Faculty Publications
The microstructure and connectivity of the ionic and electronic conductive phases in composite ceramic membranes are directly related to device performance. Transmission electron microscopy (TEM) including chemical mapping combined with X-ray nanotomography (XNT) have been used to characterize the composition and 3-D microstructure of a MIEC composite model system consisting of a Ce0.8Gd0.2O2 (GDC) oxygen ion conductive phase and a CoFe2O4 (CFO) electronic conductive phase. The microstructural data is discussed, including the composition and distribution of an emergent phase which takes the form of isolated and distinct regions. Performance implications are considered …
Piezoresistive Sensing Of Bistable Micro Mechanism State, Jeffrey K. Anderson, Larry L. Howell, Jonathan W. Wittwer, Timothy W. Mclain
Piezoresistive Sensing Of Bistable Micro Mechanism State, Jeffrey K. Anderson, Larry L. Howell, Jonathan W. Wittwer, Timothy W. Mclain
Faculty Publications
The objective of this work is to demonstrate the feasibility of on-chip sensing of bistable mechanism state using the piezoresistive properties of polysilicon, thus eliminating the need for electrical contacts. Changes in position are detected by observing changes in resistance across the mechanism. Sensing the state of bistable mechanisms is critical for various applications, including high-acceleration sensing arrays and alternative forms of nonvolatile memory. A fully compliant bistable micro mechanism was designed, fabricated, and tested to demonstrate the feasibility of this sensing technique. Testing results from two fabrication processes, SUMMiT IV and MUMPs, are presented. The SUMMiT mechanism was then …
System Safety Principles: A Multidisciplinary Engineering Perspective, Joseph Saleh, Karen Marais, Francesca Favaro
System Safety Principles: A Multidisciplinary Engineering Perspective, Joseph Saleh, Karen Marais, Francesca Favaro
Faculty Publications
System safety is of particular importance for many industries. Broadly speaking, it refers to the state or objective of striving to sustainably ensure accident prevention through actions on multiple safety levers (technical, organizational, and regulatory). While complementary to risk analysis, it is distinct in one important way: risk analysis is anticipatory rationality examining the possibility of adverse events (or accident scenarios), and the tools of risk analysis support and in some cases quantify various aspects of this analysis effort. The end-objective of risk analysis is to help identify and prioritize risks, inform risk management, and support risk communication. These tools …
Tailsitter Attitude Control Using Resolved Tilt-Twist, Timothy Mclain, Jason M. Beach, Matthew E. Argyle, Randall W. Beard, Stephen Morris
Tailsitter Attitude Control Using Resolved Tilt-Twist, Timothy Mclain, Jason M. Beach, Matthew E. Argyle, Randall W. Beard, Stephen Morris
Faculty Publications
The tailsitter aircraft merges the endurance and speed of fixed-wing aircraft with the flexibility and VTOL abilities of rotorcraft. Because of the requirement to be functional at a full range of attitudes, quaternions are typically employed to calculate attitude error. Attitude control is then accomplished by using the vector component of the error quaternion to drive flight control surfaces. This paper demonstrates that this method of driving the flight control surfaces can be suboptimal for tailsitter type aircraft and can lead to undesired vehicle movement. An alternate method of calculating attitude error called resolved tilt-twist is improved and validated. The …
A Sinteractive Ni-Bazr0.8Y0.2O3-Δ Composite Membrane For Hydrogen Separation, Shumin Fang, Siwei Wang, Kyle S. Brinkman, Fanglin Chen
A Sinteractive Ni-Bazr0.8Y0.2O3-Δ Composite Membrane For Hydrogen Separation, Shumin Fang, Siwei Wang, Kyle S. Brinkman, Fanglin Chen
Faculty Publications
BaZr0.8Y0.2O3−δ (BZY) is an excellent candidate material for hydrogen permeation membranes due to its high bulk proton conductivity, mechanical robustness, and chemical stability in H2O- and CO2-containing environments. Unfortunately, the use of BZY as a separation membrane has been greatly restrained by its highly refractory nature, poor grain boundary proton conductivity, high number of grain boundaries resulting from limited grain growth during sintering, as well as low electronic conductivity. These problems can be resolved by the fabrication of a Ni–BZY composite membrane with large BZY grains, which requires the development …