The Ionic Diffusion Model For The Solid Oxide Cathode And Its Verification By The Electrolysis Of Ta2O5 In Molten Cacl2,
2014
College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China;
The Ionic Diffusion Model For The Solid Oxide Cathode And Its Verification By The Electrolysis Of Ta2O5 In Molten Cacl2, Hua-Lin Chen, Zhi-Yong Wang, Xian-Bo Jin, George Z. Chen
Journal of Electrochemistry
The deoxidation speed of a solid oxide cathode in molten CaCl2 can be estimated by the PRS steady diffusion model of O2-, which correlates the deoxidation speed with the precursor porosity, P, the metal-to-oxide molar volume ratio, R, and the cathode volume shrinkage S. The PRS model indicates that the porosity of the oxide cathode has important influence on the deoxidation speed, and provides a very simple equation for the prediction of the optimal cathode porosity. For the electrolysis of Ta2O5, the porosity of the cathode is better to be within 50%. …
Effects Of Conformational Transformations On Electronic Transport Properties Of Optical Molecular Switches: An Ab Initio Study,
2014
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210008, China;
Effects Of Conformational Transformations On Electronic Transport Properties Of Optical Molecular Switches: An Ab Initio Study, Yuan-Yuan He, Jian-Wei Zhao
Journal of Electrochemistry
A series of model molecules with 4 kinds of conformational transformations have been investigated as optical molecular switches by using density functional theory combined with nonequilibrium Green’s function method. The theoretical calculations show that molecules after conformational transformations have photoswitching characteristics. We find that the photochromic molecules with the same conformational transformation usually have a similar current on/off state when they are applied as photoshwitches. Among these transformations, the molecular switch with E(“trans”)/Z(“cis”)-isomerisation of the NN double bond has the highest current on-off ratio. The influences of the energy gap (HLG) between the highest occupied molecular orbital (HOMO) and the …
23Na Mas Nmr Spectroscopic Study Of Na2Mnpo4F As Cathode Material For Sodium-Ion Battery,
2014
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
23Na Mas Nmr Spectroscopic Study Of Na2Mnpo4F As Cathode Material For Sodium-Ion Battery, Xu Hou, Gui-Ming Zhong, Xiao-Chen Lin, Zi-Geng Liu, Xiao-Biao Wu, Yong Yang
Journal of Electrochemistry
The Na2MnPO4F is one of the promising cathode materials for the sodium ion batteries. In the paper, we employed the ex situ X-ray diffraction and solid state NMR techniques to study the charge and discharge processes of this material, including the crystal structure and sodium sites changes. The ex situ x-ray diffraction patterns showed that two new diffraction peaks could be observed at 31o and 36o indicating an intermediate phase formed with the extraction of Na+. From the 23Na MAS NMR spectrum of the material, three peaks were seen at -209 …
Effects Of Oxygen Coverage And Hydrated Proton Model On The Dft Calculation Of Oxygen Reduction Pathways On The Pt(111) Surface,
2014
College of Chemistry and Chemical Engineering, Hunan University of Arts and Science, Changde 415000, Hunan, China;College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China;
Effects Of Oxygen Coverage And Hydrated Proton Model On The Dft Calculation Of Oxygen Reduction Pathways On The Pt(111) Surface, Li-Hui Ou, Sheng-Li Chen
Journal of Electrochemistry
DFT calculation is used to study various possible steps in the oxygen reduction reaction (ORR), including the adsorption and dissociation process of O2 and the serial protonation process of dissociated products to form H2O on the Pt(111) surface. By using slabs of different sizes, and different numbers of pre-adsorbed oxygen atoms, the coverage effects on the pathways are investigated. The calculated results using different hydrated proton models are also compared. It is shown that the initial step of the ORR is the formation of a protonated end-on chemisorbed state of OOH*, which can transform to an unprotonated …
Numerical Solution Of Burgers' Equation Arising In Longitudinal Dispersion Phenomena In Fluid Flow Through Porous Media By Crank-Nicolson Scheme,
2014
Department of Mathematics, Bhavan’s R. A. College of Science
Numerical Solution Of Burgers' Equation Arising In Longitudinal Dispersion Phenomena In Fluid Flow Through Porous Media By Crank-Nicolson Scheme, Ravi Borana, Vikas Pradhan, Manoj Mehta
5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry
The present paper discusses the numerical solution of the Burgers’ equation arising in longitudinal dispersion phenomenon in fluid flow through porous media. In the porous medium pure water, salt water or contaminated water disperse in longitudinal direction gives rise to a non-linear partial differential equation in the form of Burgers’ equation. The equation is solved by using Crank-Nicolson finite difference scheme with appropriate initial and boundary conditions. The longitudinal dispersion phenomenon may be miscible or immiscible fluid flow through porous media. The problem of miscible displacement can be seen in the coastal areas, where fresh water beds are gradually displaced …
Evaporation From A Capillary Tube: Experiment And Modelization,
2014
Université Paris-Est, Laboratoire Navier
Evaporation From A Capillary Tube: Experiment And Modelization, Emmanuel Keita, Pamela Faure, Stephane Rodts, Phillippe Coussot, David Weitz
5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry
Drying is known to play a major role in soils and buildings materials. Better understanding the physics may help saving cost and energy. Thus control of the drying kinetics is a key factor. In permeable porous media, capillary forces lead to constant curvature of the air/water interface. The value of the curvature and the shape of the interface depend strongly on the pore geometry. Thus small change in their shape may lead to main change of the air/water interface as the medium desaturates. As the surface is supplied with water the drying rate remains at a constant value set by …
Experimental Study For Air Cooling Using Membrane Covered Tray,
2014
King Saud University, Mechanical Engineering Department
Experimental Study For Air Cooling Using Membrane Covered Tray, Mohamed Ali, Obida Zeitoun, Hany Al-Ansary, Abdullah Nuhait
5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry
An experimental study is conducted to cool the outdoor air using a humidification technique. A wind tunnel was built with a membrane covered tray serves as a test section. An outdoor air passes over a tray full of water and covered with a specific membrane. Air temperatures and relative humidity are measured before and after the tray for several air and water speeds. Air speed is measured at different locations along the centerline of the cross section. Results show that as the angle of the tray increases the air temperature drop increases which improve the efficiency of the humidification technique. …
High Temperature Thermodynamic, Mechanical And Kinetic Properties From First Principles,
2014
Materials Department, University of California Santa Barbara, USA
High Temperature Thermodynamic, Mechanical And Kinetic Properties From First Principles, Anton Van Der Ven
Thermal Barrier Coatings IV
No abstract provided.
Demonstration Of Two Novel Methods For Residual Stress Management On Nial Bond Coats,
2014
Institute I: General Materials Properties, FAU Erlangen-Nuremberg
Demonstration Of Two Novel Methods For Residual Stress Management On Nial Bond Coats, Markus Krottenthaler, Karsten Durst, Mathias Goken
Thermal Barrier Coatings IV
No abstract provided.
Prediction Of The Cyclic Durability As A Function Of Cycle Duration And Temperature Of An Air Plasma Sprayed Coating Using Inelastic Strain,
2014
University of Connecticut, USA
Prediction Of The Cyclic Durability As A Function Of Cycle Duration And Temperature Of An Air Plasma Sprayed Coating Using Inelastic Strain, Eric H. Jordan, Shayan Ahmadian, Maurice Gell
Thermal Barrier Coatings IV
A detailed study of the failure mechanisms in an APS TBC was carried out involving over 1000 micrographs. As a result the kinetics of oxidation and rumpling were characterized. In addition it was found that the failure was always within the ceramic caused by progressive cracking. At approximately half the spallation life, crack linking became the dominant growth mode for cracks. This pattern of damage remained constants over the temperature range of 1066 °C to 1149 °C and for cycle durations of 0.5 hours to 50 hours. The change in temperature resulted in a variation in spallation life of a …
Use Of Liquid Pressure-Pulse Decay Permeameter In Experimental Evaluation Of Permeability In Wellbore Cement Under Geopressured Geothermal Conditions,
2014
Craft and Hawkins Department of Petroleum Engineering, Louisiana State University
Use Of Liquid Pressure-Pulse Decay Permeameter In Experimental Evaluation Of Permeability In Wellbore Cement Under Geopressured Geothermal Conditions, Kolawole Bello, Mileva Radonjic
5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry
Geopressured reservoirs in the northern Gulf of Mexico basin along the coast of Louisiana have been determined to be viable source of geothermal energy and potential sites for carbon sequestration, where CO2 can be utilized to induce convective flow of geofluids and enhance heat harvesting. These reservoirs are made of unconsolidated sandstone capped by shale layers and possess temperatures as high as 140⁰C. At high temperatures, cement strength retrogression occur when calcium silicate hydrate phase in hydrated cement converts to alpha dicalcium silicate hydrate phase. The higher the temperature, the quicker the rate of transformation of calcium silicate hydrate. The …
Nondestructive Thickness Measurements On Ebpvd Thermal Barrier Coatings By Using Terahertz Technique,
2014
MTU Aero Engines
Nondestructive Thickness Measurements On Ebpvd Thermal Barrier Coatings By Using Terahertz Technique, Thomas Cosack, Jens Klier, Joachim Jonuscheit
Thermal Barrier Coatings IV
No abstract provided.
Biomaterial Testing Methodology For Long-Term In Vivo Applications: Silicon Carbide Corrosion Resistance, Biocompatibility And Hemocompatibility,
2014
University of South Florida
Biomaterial Testing Methodology For Long-Term In Vivo Applications: Silicon Carbide Corrosion Resistance, Biocompatibility And Hemocompatibility, Maysam Nezafati
USF Tampa Graduate Theses and Dissertations
Biomedical devices that function in-vivo offer a tremendous promise to improve the quality of life for many who suffer from disease and trauma. The most important consideration for these devices is that they interact with the physiological environment as designed without initiating a deleterious inflammatory response. ISO 10993 outlines the current international guideline for investigating the biocompatibility of such devices. Numerous groups report the use of ISO 10993 as the basis for their experimental evaluation of candidate materials for neuroprosthetics, as well as other biomedical devices, however most of these reports fail to completely comply with the standard. This leads …
Heat Flow From A Buried Cylindrical Tank Partially Submerged In Groundwater,
2014
University of Auckland
Heat Flow From A Buried Cylindrical Tank Partially Submerged In Groundwater, Robert Mckibbin, Shigeo Kimura
5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry
This study was motivated by the possibility of re-use of buried cylindrical tanks, once a facility for fuel storage at motor vehicle service stations (now relinquished by oil companies), but remaining for use as thermal reservoirs connected to space heating systems (e.g. for convenience stores) in Japan. The ground in which a tank is buried is assumed to be of uniform porosity and permeability, with a phreatic groundwater surface (water table) that may rise and fall, albeit slowly, over time. The ground and the water are subject to heating and cooling according to the season and weather conditions. Here, it …
Investigation Of Transpiration Cooling With Local Thermal Non-Equilibrium Model: Effects Of Different Thermal Boundary Conditions At The Porous-Fluid Interface,
2014
Tsinghua University
Investigation Of Transpiration Cooling With Local Thermal Non-Equilibrium Model: Effects Of Different Thermal Boundary Conditions At The Porous-Fluid Interface, Zheng Huang, Yin-Hai Zhu, Pei-Xue Jiang, Yan-Bin Xiong
5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry
In this study, the main stream coupled with a porous medium with local thermal non-equilibrium assumption is analyzed. The flow inside the porous material is modelled using the Darcy–Brinkman–Forchheimer equation and the incompressible Navier-Stokes equations are solved for the main stream. Several couple conditions between the main flow temperature and the temperatures of the solid matrix and coolant flow at the fluid/porous interface is calculated. The results show that the Model C assumes the main flow temperature equals the solid phase temperature and the main flow heat flux is all imposed on the solid phase gives the most reasonable answer.
Effective Permeability Upscaling From Heterogenous To Homogenous Porous Media,
2014
University of Oklahoma Norman Campus
Effective Permeability Upscaling From Heterogenous To Homogenous Porous Media, Mehmet Cicek, Deepak Devegowda, Faruk Civan, Richard Sigal
5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry
An effective method to upscale permeability is presented to represent a heterogeneous reservoir with homogeneous permeability and porosity values. As a result, there is no need to deal with dual-porosity or dual-permeability models in reservoir simulations. Thus, the required CPU time for reservoir production and flow simulations is reduced significantly.
Modified Rhie-Chow / Piso Algorithm For Collocated Variable Finite Porous Media Flow Solvers,
2014
Phillip Morris International R&D
Modified Rhie-Chow / Piso Algorithm For Collocated Variable Finite Porous Media Flow Solvers, Markus Nordlund
5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry
A modified Rhie-Chow/ PISO segregated algorithm is proposed, whic by construction avoids the development of spurious oscillations in the solution fields for low Mach number flow in heterogeneous, isotropic porous media. The collocated variable finite volume based algorithm modifies the commonly used Rhie-Chow interpolation to maintain a strong pressure-velocity coupling when large discontinuous implicit momentum sources are present. This Redistributed Resistivity PISO algorithm is based on a redistribution of the flow resistivity over the neighboring grid cells to the discontinuity. The proposed algorithm is successfully verified against published data for the velocity and pressure for two cases. The robustness of …
Pressure Transient Characteristics Of Multi-Stage Fractured Horizontal Wells In Shale Gas Reservoirs With Consideration Of Multiple Mechanisms,
2014
State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University
Pressure Transient Characteristics Of Multi-Stage Fractured Horizontal Wells In Shale Gas Reservoirs With Consideration Of Multiple Mechanisms, Jingjing Guo, Liehui Zhang, Haitao Wang
5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry
The approach of multi-stage fractured horizontal wells (MFHWs) has been proven an efficient technology for successful development of shale gas reservoirs. Together with multiple gas flow mechanisms, the existence of multiple hydraulic fractures further complicates the gas flowing problem in shale gas reservoirs. Understanding pressure transient dynamics of MFHWs in shale gas reservoirs is of great importance to provide a perception into long-term pressure dynamics forecast as well as to estimate relevant reservoir and fracturing parameters. This paper presents a comprehensive seepage model to investigate the characteristics of pressure transient responses of a horizontal well intercepted by multiple finitely conductive …
Turbulence In Porous Media: Some Fundamental Questions Addressed By Dns Solutions,
2014
Hamburg University of Technology
Turbulence In Porous Media: Some Fundamental Questions Addressed By Dns Solutions, Marc Florian Uth, Y. Jin, A. V. Kuznetsov, H. Herwig
5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry
In a generic porous matrix built by a large number of rectangular bars the flow is determined numerically by a DNS approach. Turbulent flow is thus simulated avoiding modelling in order to decide whether turbulent structures with scales much larger than the pore scale exist. So far only under-resolved DNS solutions are determined from which, however, definite conclusions with respect to the maximum turbulent length scale can be drawn.
Numerical Solutions Of Non-Linear Fractional Transport Models In Unconventional Hydrocarbon Reservoirs Using Variational Iteration Method,
2014
King Fahd University of Petroleum and Minerals
Numerical Solutions Of Non-Linear Fractional Transport Models In Unconventional Hydrocarbon Reservoirs Using Variational Iteration Method, Nadeen Malik, Iftikhar Ali, Bilal Chanane
5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry
Unconventional hydrocarbon reservoirs, such as, shale gas deposits, offer a new source of energy resources. These reservoirs consist of tight porous rocks which are characterized by nano-scale size porous networks with ultra-low permeability. The mathematical modeling of phenomena through such tight porous media provides its own challenges. In this study, we consider a relatively new approach by modeling the transport of gas by the time-fractional advection-diffusion equation,
