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2014

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Articles 211 - 240 of 616

Full-Text Articles in Materials Science and Engineering

Synthesis And Characterization Of Cdse/Zns Core/Shell Quantum Dot Sensitized Pcpdtbt-P3ht:Pcbm Organic Photovoltaics, Buddy J. Bump Jul 2014

Synthesis And Characterization Of Cdse/Zns Core/Shell Quantum Dot Sensitized Pcpdtbt-P3ht:Pcbm Organic Photovoltaics, Buddy J. Bump

Master's Theses

Durable, cheap, and lightweight polymer based solar cells are needed, if simply to meet the demand for decentralized electrical power production in traditionally “off-grid” areas. Using a blend of Poly(3-hexylthiophene-2,5-diyl) (P3HT), Phenyl-C61-butyric acid methyl ester (PCBM), and the low band-gap polymer Poly[2,6-(4,4-bis-(2- ethylhexyl)-4H-cyclopenta [2,1-b;3,4-b′]dithiophene)-alt-4,7(2,1,3-benzothiadiazole)] (PCPDTBT), we have fabricated devices with a wide spectral response and 3% power conversion efficiency in AM 1.5 conditions; however, this thin film system exhibits only 0.43 optical density at 500 nm. To improve the performance of this polymer blend photovoltaic, we aim to increase absorption by adding CdSe(ZnS) core (shell) quantum dots. Four groups of …

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Correlation Between Microstructure And Thermionic Electron Emission From Os-Ru Thin Films On Dispenser Cathodes, Phillip D. Swartzentruber, Thomas John Balk, Michael P. Effgen Jul 2014

Correlation Between Microstructure And Thermionic Electron Emission From Os-Ru Thin Films On Dispenser Cathodes, Phillip D. Swartzentruber, Thomas John Balk, Michael P. Effgen

Chemical and Materials Engineering Faculty Publications

Osmium-ruthenium films with different microstructures were deposited onto dispenser cathodes and subjected to 1000 h of close-spaced diode testing. Tailored microstructures were achieved by applying substrate biasing during deposition, and these were evaluated with scanning electron microscopy, x-ray diffraction, and energy dispersive x-ray spectroscopy before and after close-spaced diode testing. Knee temperatures determined from the close-spaced diode test data were used to evaluate cathode performance. Cathodes with a large {10-11} Os-Ru film texture possessed comparatively low knee temperatures. Furthermore, a low knee temperature correlated with a low effective work function as calculated from the close-spaced diode data. It is proposed …

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Monoclinic Phases Arising Across Thermal Inter-Ferroelectric Phase Transitions, Yijia Gu, Fei Xue, Shiming Lei, Tom T. A. Lummen, Jianjun Wang, For Full List Of Authors, See Publisher's Website. Jul 2014

Monoclinic Phases Arising Across Thermal Inter-Ferroelectric Phase Transitions, Yijia Gu, Fei Xue, Shiming Lei, Tom T. A. Lummen, Jianjun Wang, For Full List Of Authors, See Publisher's Website.

Materials Science and Engineering Faculty Research & Creative Works

Thermotropic phase boundaries (TPBs), as thermal analogs of morphotropic phase boundaries (MPBs), are associated with the thermal inter-ferroelectric phase transitions. Similar to an MPB, a TPB exhibits a characteristically flattened energy profile which favors polarization rotation, thus giving rise to a structurally bridging low-symmetry phase. We report on the kinetic process of thermal inter-ferroelectric phase transitions in BaTiO3 and KNbO3 using the phase-field method. The domain structures are found to play key roles in stabilizing the monoclinic phase. In simple domain structures, the monoclinic phase is a transient phase and cannot be stabilized into its neighboring phase regimes. …

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An Investigation Of The Effect Of Direct Metal Deposition Parameters On The Characteristics Of The Deposited Layers, Tarak A. Amine, Joseph William Newkirk, Frank W. Liou Jul 2014

An Investigation Of The Effect Of Direct Metal Deposition Parameters On The Characteristics Of The Deposited Layers, Tarak A. Amine, Joseph William Newkirk, Frank W. Liou

Materials Science and Engineering Faculty Research & Creative Works

Multilayer direct laser deposition (DLD) is a fabrication process through which parts are fabricated by creating a molten pool into which metal powder is injected as particles. During fabrication, complex thermal activity occurs in different regions of the build; for example, newly deposited layers will reheat previously deposited layers. The objective of this study was to provide insight into the thermal activity that occurs during the DLD process. This work focused on the effect of the laser parameters of newly deposited layers on the microstructure and mechanical properties of the previously deposited layers in order to characterize these effects to …

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Modulating Notochordal Differentiation Of Human Induced Pluripotent Stem Cells Using Natural Nucleus Pulposus Tissue Matrix, Yongxing Liu, M. N. Rahaman, B. Sonny Bal Jul 2014

Modulating Notochordal Differentiation Of Human Induced Pluripotent Stem Cells Using Natural Nucleus Pulposus Tissue Matrix, Yongxing Liu, M. N. Rahaman, B. Sonny Bal

Materials Science and Engineering Faculty Research & Creative Works

Human induced pluripotent stem cells (hiPSCs) can differentiate into notochordal cell (NC)-like cells when cultured in the presence of natural porcine nucleus pulposus (NP) tissue matrix. The method promises massive production of high-quality, functional cells to treat degenerative intervertebral discs (IVDs). Based on our previous work, we further examined the effect of cell-NP matrix contact and culture medium on the differentiation, and further assessed the functional differentiation ability of the generated NC-like. The study showed that direct contact between hiPSCs and NP matrix can promote the differentiation yield, whilst both the contact and non-contact cultures can generate functional NC-like cells. …

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Overview Of Instruments For Investigating Dust Interactions On Small Solar System Bodies By Landers And Rovers, Ryan L. Kobrick, Jeffrey A. Hoffman, Kenneth W. Street Jr., Douglas L. Rickman Jul 2014

Overview Of Instruments For Investigating Dust Interactions On Small Solar System Bodies By Landers And Rovers, Ryan L. Kobrick, Jeffrey A. Hoffman, Kenneth W. Street Jr., Douglas L. Rickman

Publications

Small Solar System bodies such as asteroids, comets and Mars' moons Phobos and Deimos have relatively unknown regolith environments. It is hypothesized that dust preserved in the regolith on the surfaces will have similar mechanical properties to lunar dust because of similar formation processes from micrometeoric bombardment, low relative gravity for slow settling times, and virtually no weathering because there is no atmosphere.

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Shape Fixity And Shape Recovery Characteristics Of Aliphatic Epoxy-Benzoxazine Shape Memory Polymer, T Tanpitaksit, M Okhawilai, S Rimdusit Jul 2014

Shape Fixity And Shape Recovery Characteristics Of Aliphatic Epoxy-Benzoxazine Shape Memory Polymer, T Tanpitaksit, M Okhawilai, S Rimdusit

Journal of Metals, Materials and Minerals

Shape memory polymers (SMPs) are polymers that can fix the temporary shape and recover to the permanent shape by external stimuli. Epoxy resins are an important family of SMPs due to their excellent stability, thermomechanical endurance and the high values of shape fixity. However, epoxide ring opening polymerization required a curing agent which possesses some disadvantages such as high cost, toxic problem to the user and corrosion to the processing apparatus. In this research, novel series of SMPs were prepared from aliphatic epoxy as soft segment and benzoxazine resin (BA-a) as hard segment. Additionally, benzoxazine resin can also function as …

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Development Of Electronic Packages From Polypropylene/Ethylene Propylene Rubber Blends: A Double Percolation Approach, S Phromdee, P Lorjai, S Tiptipakorn, S Rimdusit Jul 2014

Development Of Electronic Packages From Polypropylene/Ethylene Propylene Rubber Blends: A Double Percolation Approach, S Phromdee, P Lorjai, S Tiptipakorn, S Rimdusit

Journal of Metals, Materials and Minerals

Volume resistivity of less than 104 W.cm is required for typical electrically conductive packages. Conductive polypropylene (PP) packages with the above level of conductivity value can be achieved by a use of carbon black (CB) as conductive filler. To maintain processability of PP with low cost, minimal amount of carbon black is preferable in the conductive composites. By introducing a second polymer with immiscible or partially miscible nature to the first polymer, and if the conductive filler is localized in one polymer phase, a system of double percolation with minimal filler content can be achieved. In this work, electrically conductive …

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Property Enhancement Of Polybenzoxazine Modified With Maleic Anhydride, W Punuch, M Okhawilai, S Rimdusit Jul 2014

Property Enhancement Of Polybenzoxazine Modified With Maleic Anhydride, W Punuch, M Okhawilai, S Rimdusit

Journal of Metals, Materials and Minerals

One seemingly shortcoming of polybenzoxazine is its relatively high rigidity. Therefore, various efforts have been attempted to toughen polybenzoxazine such as by alloying with more flexible monomers or polymers e.g. urethane elastomers or flexible epoxy. The alloying of polybenzoxazine with those resins or polymers has been reported to show synergy in some properties thus economically provide a novel class of resin systems with superior performance. In this work, polybenzoxazine alloys were prepared from bisphenol-A-aniline based benzoxazine resin (BA-a) and maleic anhydride (MA) in N, N-Dimethyformamide (DMF) solvent. The miscible monomer mixture was easily transformed into transparent polymer alloys by thermal …

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Nickel Aluminum Shape Memory Alloys Via Molecular Dynamics, Keith Ryan Morrison Jul 2014

Nickel Aluminum Shape Memory Alloys Via Molecular Dynamics, Keith Ryan Morrison

Open Access Theses

Shape memory materials are an important class of active materials with a wide range of applications in the aerospace, biomedical, and automobile industries. These materials exhibit the two unique properties of shape memory and superelasticity. Shape memory is the ability to recover its original shape by applying heat after undergoing large deformations. Superelasticity is the ability to undergo large, reversible deformations (up to 10%) that revert back when the load is removed. These special properties originate from a reversible, diffusionless solid-solid phase transformation that occurs between a high temperature austenite phase and a low temperature martensite phase. The development of …

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Preparation & Characterization Of High Purity Cu2 Znsn(Sxse1-X)4 Nanoparticles, Bethlehem G. Negash Jul 2014

Preparation & Characterization Of High Purity Cu2 Znsn(Sxse1-X)4 Nanoparticles, Bethlehem G. Negash

Open Access Theses

Research in thin film solar cells applies novel techniques to synthesize cost effective and highly efficient absorber materials in order to generate electricity directly from solar energy. Of these materials, copper zinc tin sulfoselenide (Cu2ZnSn(SxSe1-x) 4) nanoparticles have shown great promise in solar cell applications due to optimal material properties as well as low cost & relative abundance of materials.1,2 Sulfoselenide nanoparticles have also a broader impact in other industries including electronics3, LED 4, and biomedical research5. Of the many routes of manufacturing these class of semiconductors, …

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Correlating Grain Size To Radiation Damage Tolerance Of Tungsten Materials Exposed To Relevant Fusion Conditions, Sean Robert Gonderman Jul 2014

Correlating Grain Size To Radiation Damage Tolerance Of Tungsten Materials Exposed To Relevant Fusion Conditions, Sean Robert Gonderman

Open Access Theses

Tungsten remains a leading candidate for plasma facing component (PFC) in future fusion devices. This is in large part due to its strong thermal and mechanical properties. The ITER project has already chosen to use an all tungsten divertor. Despite having a high melting temperature and low erosion rate, tungsten faces a large variety of issues when subject to fusion like conditions. These include embrittlement, melting, and extreme morphology change (growth of fuzz nanostructure). The work presented here investigates mechanisms that drive surface morphology change in tungsten materials exposed to fusion relevant plasmas. Specifically, tungsten materials of different grain sizes …

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Technology, Science, And Environtmental Impact Of A Novel Cu-Ag Core-Shell Solderless Interconnect System, Milea Joy Kammer Jul 2014

Technology, Science, And Environtmental Impact Of A Novel Cu-Ag Core-Shell Solderless Interconnect System, Milea Joy Kammer

Open Access Dissertations

Tin-based solder is ubiquitous in microelectronics manufacturing and plays a critical role in electronic packaging and attachment. While manufacturers of consumer electronics have made the transition to the use of lead-free solder, there are still a variety of reliability issues associated with these lead-free alternatives, particularly for high performance, high reliability applications. Because of these performance short-comings, researchers are still searching for a material, an alloy, or a unique alternative that can meet the thermal, mechanical, and electrical requirements for conventional reflow solder applications. In an effort to produce a more reliable alternative, Kim et al. proposed the low-temperature (200°C) …

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A New Silver Electrode Based On The Composite Silver Sulfide/Attapulgite As Ionophore, Wen-Zhuo Li, Ding-Jia Xu, Jun Wang, Jian-Long Wang Jun 2014

A New Silver Electrode Based On The Composite Silver Sulfide/Attapulgite As Ionophore, Wen-Zhuo Li, Ding-Jia Xu, Jun Wang, Jian-Long Wang

Journal of Electrochemistry

A novel silver ion selective electrode with its ionophore being a kind of organic/inorganic composite composed of silver sulfide and attapulgite has been prepared. Attapulgite is a type of natural inorganic polymer which has some properties similar to zeolite, such as a higher specific surface area and plenty of intercrystalline cavities. In this work, the silver ions were firstly adosrbed in the micropores of the attapulgite, then thioacetamidetiny was selected to mix with the prepared silver ions/ attapulgite composite. Owning to the existence of sulfur atoms in the structure of thioacetamide molecules, thioacetamide molecules can react with the silver ions/attapulgite …

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Surface Enhanced Raman Spectroscopic Studies Of Pyridine Adsorbed On Ti/Au@Sio2 Film Electrode, Min-Min Xu, Ke Liu, Qing-Hua Guo, Jian-Lin Yao Jun 2014

Surface Enhanced Raman Spectroscopic Studies Of Pyridine Adsorbed On Ti/Au@Sio2 Film Electrode, Min-Min Xu, Ke Liu, Qing-Hua Guo, Jian-Lin Yao

Journal of Electrochemistry

This study was performed based on shell-isolated nanoparticles-enhanced Raman spectroscopy (SHINERS) technology. The Au@SiO2 nanoparticles were prepared and characterized by TEM and cyclic voltammetry. It was shown that the shell of SiO2 was compact. The high quality signal measured by surface enhanced Raman spectroscopy (SERS) was obtained from the adsorbed pyridine on Ti/Au@SiO2 electrode. The origin of the SERS signals was further confirmed by testing Pt and Ni electrodes. In addition, potential dependent adsorption behavior was investigated. It was found that pyridine was adsorbed parallel on the surface from -0.1 V to -0.6 V, and converted to …

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Horseradish Peroxidase-Attapulgite Clay Nanocomposites: Fabrication And Application To Sensing The Extracellular H2O2 Released From Cells, Ping Wu, Chen-Xin Cai Jun 2014

Horseradish Peroxidase-Attapulgite Clay Nanocomposites: Fabrication And Application To Sensing The Extracellular H2O2 Released From Cells, Ping Wu, Chen-Xin Cai

Journal of Electrochemistry

The nanostructured attapulgite clay was employed as a support matrix for immobilizing horseradish peroxidase (HRP). FTIR and electrochemical methods demonstrated that HRP had been effectively assembled on attapulgite surface with the formation of HRP-attapulgite nanocomposites. The HRP-attapulgite hybrid was deposited on the glassy carbon (GC) electrode forming the HRP-attapulgite/GC electrode. Cyclic voltammetric results showed a pair of well-defined redox peaks, which were ascribed to direct electron transfer (DET) of HRP, with the formal potential E0′ = -335 mV (vs. SCE) in the phosphate buffer solution (PBS, pH 7.0). The dependence of E0′ on solution pH indicated …

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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 Jun 2014

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%. …

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Effects Of Conformational Transformations On Electronic Transport Properties Of Optical Molecular Switches: An Ab Initio Study, Yuan-Yuan He, Jian-Wei Zhao Jun 2014

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 …

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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 Jun 2014

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 …

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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 Jun 2014

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 …

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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 Jun 2014

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 …

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Evaporation From A Capillary Tube: Experiment And Modelization, Emmanuel Keita, Pamela Faure, Stephane Rodts, Phillippe Coussot, David Weitz Jun 2014

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 …

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Experimental Study For Air Cooling Using Membrane Covered Tray, Mohamed Ali, Obida Zeitoun, Hany Al-Ansary, Abdullah Nuhait Jun 2014

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. …

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High Temperature Thermodynamic, Mechanical And Kinetic Properties From First Principles, Anton Van Der Ven Jun 2014

High Temperature Thermodynamic, Mechanical And Kinetic Properties From First Principles, Anton Van Der Ven

Thermal Barrier Coatings IV

No abstract provided.

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Demonstration Of Two Novel Methods For Residual Stress Management On Nial Bond Coats, Markus Krottenthaler, Karsten Durst, Mathias Goken Jun 2014

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.

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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 Jun 2014

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 …

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Use Of Liquid Pressure-Pulse Decay Permeameter In Experimental Evaluation Of Permeability In Wellbore Cement Under Geopressured Geothermal Conditions, Kolawole Bello, Mileva Radonjic Jun 2014

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 …

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Nondestructive Thickness Measurements On Ebpvd Thermal Barrier Coatings By Using Terahertz Technique, Thomas Cosack, Jens Klier, Joachim Jonuscheit Jun 2014

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.

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Biomaterial Testing Methodology For Long-Term In Vivo Applications: Silicon Carbide Corrosion Resistance, Biocompatibility And Hemocompatibility, Maysam Nezafati Jun 2014

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 …

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Heat Flow From A Buried Cylindrical Tank Partially Submerged In Groundwater, Robert Mckibbin, Shigeo Kimura Jun 2014

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 …

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