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Full-Text Articles in Physical Sciences and Mathematics
Origin Of The Unique Activity Of Pt/Tio2 Catalysts For The Water–Gas Shift Reaction, Salai Ammal, Andreas Heyden
Origin Of The Unique Activity Of Pt/Tio2 Catalysts For The Water–Gas Shift Reaction, Salai Ammal, Andreas Heyden
Salai C. Ammal
No abstract provided.
Theoretical Investigation Of H2 Oxidation On The Sr2Fe1.5Mo0.5O6 (001) Perovskite Surface Under Anodic Solid Oxide Fuel Cell Conditions, S. Suthirakun, Salai Ammal, A. Muñoz-García, G. Xiao, Fanglin Chen, Hans-Conrad Zur Loye, E. Carter, Andreas Heyden
Theoretical Investigation Of H2 Oxidation On The Sr2Fe1.5Mo0.5O6 (001) Perovskite Surface Under Anodic Solid Oxide Fuel Cell Conditions, S. Suthirakun, Salai Ammal, A. Muñoz-García, G. Xiao, Fanglin Chen, Hans-Conrad Zur Loye, E. Carter, Andreas Heyden
Salai C. Ammal
No abstract provided.
Obtaining Mixed Ionic/Electronic Conductivity In Perovskite Oxides In A Reducing Environment: A Computational Prediction For Doped Srtio3, S. Suthirakun, Salai Ammal, G. Xiao, Fanglin Chen, Kevin Huang, Hans-Conrad Zur Loye, Andreas Heyden
Obtaining Mixed Ionic/Electronic Conductivity In Perovskite Oxides In A Reducing Environment: A Computational Prediction For Doped Srtio3, S. Suthirakun, Salai Ammal, G. Xiao, Fanglin Chen, Kevin Huang, Hans-Conrad Zur Loye, Andreas Heyden
Salai C. Ammal
No abstract provided.
L-Shaped Three-Center Two-Electron (C−C−C)+ Bonding Array, N. Yoshikai, Salai Ammal, E. Nakamura
L-Shaped Three-Center Two-Electron (C−C−C)+ Bonding Array, N. Yoshikai, Salai Ammal, E. Nakamura
Salai C. Ammal
No abstract provided.
On The Importance Of Metal–Oxide Interface Sites For The Water–Gas Shift Reaction Over Pt/Ceo2 Catalysts, S. Aranifard, Salai Ammal, Andreas Heyden
On The Importance Of Metal–Oxide Interface Sites For The Water–Gas Shift Reaction Over Pt/Ceo2 Catalysts, S. Aranifard, Salai Ammal, Andreas Heyden
Salai C. Ammal
No abstract provided.
Synergistic Dimetallic Effects In Propargylic Substitution Reaction Catalyzed By Thiolate-Bridged Diruthenium Complex, Salai Ammal, N. Yoshikai, Y. Inada, Y. Nishibayashi, E. Nakamura
Synergistic Dimetallic Effects In Propargylic Substitution Reaction Catalyzed By Thiolate-Bridged Diruthenium Complex, Salai Ammal, N. Yoshikai, Y. Inada, Y. Nishibayashi, E. Nakamura
Salai C. Ammal
No abstract provided.
Combinatorial Computational Chemistry Approach To The Design Of Metal Oxide Electronics Materials, B. Rodion, Salai Ammal, Y. Inaba, Y. Oumi, S. Takami, M. Kubo, A. Miyamoto, M. Kawasaki, M. Yoshimoto, H. Koinuma
Combinatorial Computational Chemistry Approach To The Design Of Metal Oxide Electronics Materials, B. Rodion, Salai Ammal, Y. Inaba, Y. Oumi, S. Takami, M. Kubo, A. Miyamoto, M. Kawasaki, M. Yoshimoto, H. Koinuma
Salai C. Ammal
Combinatorial chemistry has been developed as an experimental method where it is possible to synthesize hundreds of samples all at once and examine their properties. Recently, we introduced the concept of combinatorial approach to computational chemistry for material design and proposed a new method called `a combinatorial computational chemistry'. In this approach, the effects of large number of dopants, substrates, and buffer layers on the structures, electronic states, and properties of metal oxide electronics material is estimated systematically using computer simulations techniques, in order to predict the best dopant, substrate, and buffer layer for each metal oxide electronics materials.
Density Functional Theory Study On The Electronic Structure Of N- And P-Type Doped Srtio3 At Anodic Solid Oxide Fuel Cell Conditions, S. Suthirakun, Salai Ammal, G. Xiao, Fanglin Chen, Hans-Conrad Zur Loye, Andreas Heyden
Density Functional Theory Study On The Electronic Structure Of N- And P-Type Doped Srtio3 At Anodic Solid Oxide Fuel Cell Conditions, S. Suthirakun, Salai Ammal, G. Xiao, Fanglin Chen, Hans-Conrad Zur Loye, Andreas Heyden
Salai C. Ammal
The electronic conductivity and thermodynamic stability of mixed n-type and p-type doped SrTiO3 have been investigated at anodic solid oxide fuel cell (SOFC) conditions using density functional theory (DFT) calculations. In particular, constrained ab initio thermodynamic calculations have been performed to evaluate the phase stability and reducibility of various Nb- and Ga-doped SrTiO3 at synthesized and anodic SOFC conditions. The density of states (DOS) of these materials was analyzed to study the effects of n- and p-doping on the electronic conductivity. In agreement with experimental observations, we find that the transformation from 20% Nb-doped Sr-deficient SrTiO3 to a non-Sr-deficient phase …
Data Management And Visualization Of X-Ray Diffraction Spectra From Thin Film Ternary Composition Spreads, I. Takeuchi, C. Long, O. Famodu, M. Murakami, Jason Hattrick-Simpers, G. Rubloff, M. Stukowski, K. Rajan
Data Management And Visualization Of X-Ray Diffraction Spectra From Thin Film Ternary Composition Spreads, I. Takeuchi, C. Long, O. Famodu, M. Murakami, Jason Hattrick-Simpers, G. Rubloff, M. Stukowski, K. Rajan
Jason R. Hattrick-Simpers
We discuss techniques for managing and visualizing x-ray diffraction spectrum data for thin film composition spreads which map large fractions of ternary compositional phase diagrams. An in-house x-ray microdiffractometer is used to obtain spectra from over 500 different compositions on an individual spread. The MATLAB software is used to quickly organize the data and create various plots from which one can quickly grasp different information regarding structural and phase changes across the composition spreads. Such exercises are valuable in rapidly assessing the “overall” picture of the structural evolution across phase diagrams before focusing in on specific composition regions for detailed …
The Effect Of Copt Crystallinity And Grain Texturing On Properties Of Exchange-Coupled Fe/Copt Systems, H. Oguchi, A. Zambano, M. Yu, Jason Hattrick-Simpers, D. Banerjee, Y. Liu, Z. Wang, J. Liu, S. Lofland, D. Josell, I. Takeuchi
The Effect Of Copt Crystallinity And Grain Texturing On Properties Of Exchange-Coupled Fe/Copt Systems, H. Oguchi, A. Zambano, M. Yu, Jason Hattrick-Simpers, D. Banerjee, Y. Liu, Z. Wang, J. Liu, S. Lofland, D. Josell, I. Takeuchi
Jason R. Hattrick-Simpers
The effect of the crystallinity and the grain texturing of CoPt hard layers on exchange coupled Fe/CoPt soft/hard magnetic systems was studied using gradient thickness multilayer thin films. We have studied the hard layer structures by transmission electron microscopy and x-ray diffraction, and characterized the exchange coupling interaction through magnetization loops obtained by the magneto-optical Kerr effect measurement. We found that exchange coupling strongly depends on the crystalline characteristics of the CoPt hard layer. There is correlation between the mixture of different grain orientations of the CoPt hard layer and coupling efficiency. In particular, interlayer coupling is enhanced when there …
Applications Of High Throughput (Combinatorial) Methodologies To Electronic, Magnetic, Optical, And Energy-Related Materials, Martin L. Green, Ichiro Takeuchi, Jason R. Hattrick-Simpers
Applications Of High Throughput (Combinatorial) Methodologies To Electronic, Magnetic, Optical, And Energy-Related Materials, Martin L. Green, Ichiro Takeuchi, Jason R. Hattrick-Simpers
Jason R. Hattrick-Simpers
High throughput (combinatorial) materials science methodology is a relatively new research paradigm that offers the promise of rapid and efficient materials screening, optimization, and discovery. The paradigm started in the pharmaceutical industry but was rapidly adopted to accelerate materials research in a wide variety of areas. High throughput experiments are characterized by synthesis of a “library” sample that contains the materials variation of interest (typically composition), and rapid and localized measurement schemes that result in massive data sets. Because the data are collected at the same time on the same “library” sample, they can be highly uniform with respect to …
Rapid Structural Mapping Of Ternary Metallic Alloy Systems Using The Combinatorial Approach And Cluster Analysis, C. Long, Jason Hattrick-Simpers, M. Murakami, R. Srivastava, I. Takeuchi, V. Karen, X. Li
Rapid Structural Mapping Of Ternary Metallic Alloy Systems Using The Combinatorial Approach And Cluster Analysis, C. Long, Jason Hattrick-Simpers, M. Murakami, R. Srivastava, I. Takeuchi, V. Karen, X. Li
Jason R. Hattrick-Simpers
We are developing a procedure for the quick identification of structural phases in thin film composition spread experiments which map large fractions of compositional phase diagrams of ternary metallic alloy systems. An in-house scanning x-ray microdiffractometer is used to obtain x-ray spectra from 273 different compositions on a single composition spread library. A cluster analysissoftware is then used to sort the spectra into groups in order to rapidly discover the distribution of phases on the ternary diagram. The most representative pattern of each group is then compared to a database of known structures to identify known phases. Using this method, …
Interphase Exchange Coupling In Fe/Sm-Co Bilayers With Gradient Fe Thickness, Ming-Hui Yu, Jason Hattrick-Simpers, Ichiro Takeuchi, Jing Li, Z. Wang, J. Liu, S. Lofland, Somdev Tyagi, J. Freeland, D. Giubertoni, M. Bersani, M. Anderle
Interphase Exchange Coupling In Fe/Sm-Co Bilayers With Gradient Fe Thickness, Ming-Hui Yu, Jason Hattrick-Simpers, Ichiro Takeuchi, Jing Li, Z. Wang, J. Liu, S. Lofland, Somdev Tyagi, J. Freeland, D. Giubertoni, M. Bersani, M. Anderle
Jason R. Hattrick-Simpers
We have fabricated Fe∕Sm–Co bilayers with gradient Fe thicknesses in order to systematically study the dependence of exchange coupling on the thickness of the Fe layer. The Fe layer was deposited at two different temperatures (150 and 300°C) to study the effect of deposition temperature on the exchange coupling. Magneto-optical Kerr effect and x-ray magnetic circular dichroism (XMCD) have been employed as nondestructive rapid characterization tools to map the magnetic properties of the gradient samples. Systematic enhancement in exchange coupling between the soft layer and the hard layer is observed as the soft layer thickness is decreased. Separate exchange couplings …
High-Throughput Screening Of Shape Memory Alloy Thin-Film Spreads Using Nanoindentation, Arpit Dwivedi, Thomas Wyrobek, Oden Warren, Jason Hattrick-Simpers, Olubenga Famodu, Ichiro Takeuchi
High-Throughput Screening Of Shape Memory Alloy Thin-Film Spreads Using Nanoindentation, Arpit Dwivedi, Thomas Wyrobek, Oden Warren, Jason Hattrick-Simpers, Olubenga Famodu, Ichiro Takeuchi
Jason R. Hattrick-Simpers
We have demonstrated the utility of nanoindentation as a rapid characterization tool for mapping shape memoryalloy compositions in combinatorial thin-film libraries. Nanoindentation was performed on Ni–Mn–Al ternary composition spreads. The indentation hardness and the reduced elastic modulus were mapped across a large fraction of the ternary phase diagram. The large shape memoryalloy composition region, located around the Heusler composition (Ni2MnAl), was found to display significant departure in these mechanical properties from the rest of the composition spread. In particular, the modulus and the hardness values are lower for the martensite region than those of the rest of the phase diagram.
Note: A Simple Thermal Gradient Annealing Unit For The Treatment Of Thin Films, C. Metting, Johnathan Bunn, Ellen Underwood, Yihao Zhu, G. Koley, T. Crawford, Jason Hattrick-Simpers
Note: A Simple Thermal Gradient Annealing Unit For The Treatment Of Thin Films, C. Metting, Johnathan Bunn, Ellen Underwood, Yihao Zhu, G. Koley, T. Crawford, Jason Hattrick-Simpers
Jason R. Hattrick-Simpers
A gradient annealing cell has been developed for the high-throughput study of thermalannealing effects on thin-film libraries in different environments. The inexpensive gradientannealing unit permits temperature gradients as large as 28 °C/mm and can accommodate samples ranging in length from 13 mm to 51 mm. The system was validated by investigating the effects of annealing temperature on the crystallinity, resistivity, and transparency of tin-doped indium oxide deposited on a glass substrate by magnetron sputtering. The unit developed in this work will permit the rapid optimization of materials properties such as crystallinity, homogeneity, and conductivity across a variety of applications.
Combinatorial Investigation Of Magnetostriction In Fe-Fa And Fe-Ga-Al, Jason R. Hattrick-Simpers, Dwight Hunter, Corneliu M. Craciunescu, Kyu Sung Jang, Makoto Murakami, James Cullen, Manfred Wuttig, Ichiro Takeuchi, Samuel E. Lofland, Leonid Bendersky, Noble Woo, Robert Bruce Vandover, Toshiya Takahashi, Yasubumi Furuya
Combinatorial Investigation Of Magnetostriction In Fe-Fa And Fe-Ga-Al, Jason R. Hattrick-Simpers, Dwight Hunter, Corneliu M. Craciunescu, Kyu Sung Jang, Makoto Murakami, James Cullen, Manfred Wuttig, Ichiro Takeuchi, Samuel E. Lofland, Leonid Bendersky, Noble Woo, Robert Bruce Vandover, Toshiya Takahashi, Yasubumi Furuya
Jason R. Hattrick-Simpers
A high-throughput high-sensitivity optical technique for measuringmagnetostriction of thin-film composition-spread samples has been developed. It determines the magnetostriction by measuring the induced deflection of micromachined cantilever unimorph samples. Magnetostrictionmeasurements have been performed on as-deposited Fe–Ga and Fe–Ga–Al thin-film composition spreads. The thin-film Fe–Ga spreads display a similar compositional variation of magnetostriction as bulk. A previously undiscovered peak in magnetostriction at low Ga content was also observed and attributed to a maximum in the magnetocrystalline anisotropy. Magnetostrictive mapping of the Fe–Ga–Al ternary system reveals the possibility of substituting up to 8at.%Al in Fe70Ga30 without significant degradation of magnetostriction.
Characterization Of Magnetic Degradation Mechanism In A High Neutron-Flux Environment, Adib Samin, Jie Qiu, Jason Hattrick-Simpers, Liyang Dai-Hattrick, Yuan Zheng, Lei Cao
Characterization Of Magnetic Degradation Mechanism In A High Neutron-Flux Environment, Adib Samin, Jie Qiu, Jason Hattrick-Simpers, Liyang Dai-Hattrick, Yuan Zheng, Lei Cao
Jason R. Hattrick-Simpers
No abstract provided.
Optical Cell For Combinatorial In Situ Raman Spectroscopic Measurements Of Hydrogen Storage Materials At High Pressures And Temperatures, Jason Hattrick-Simpers, Wilbur Hurst, Sesha Srinivasan, James Maslar
Optical Cell For Combinatorial In Situ Raman Spectroscopic Measurements Of Hydrogen Storage Materials At High Pressures And Temperatures, Jason Hattrick-Simpers, Wilbur Hurst, Sesha Srinivasan, James Maslar
Jason R. Hattrick-Simpers
An optical cell is described for high-throughput backscattering Raman spectroscopic measurements of hydrogen storagematerials at pressures up to 10 MPa and temperatures up to 823 K. High throughput is obtained by employing a 60 mm diameter × 9 mm thick sapphire window, with a corresponding 50 mm diameter unobstructed optical aperture. To reproducibly seal this relatively large window to the cell body at elevated temperatures and pressures, a gold o-ring is employed. The sample holder-to-window distance is adjustable, making this cell design compatible with optical measurement systems incorporating lenses of significantly different focal lengths, e.g., microscope objectives and single element …
Demonstration Of Magnetoelectric Scanning Probe Microscopy, Jason R. Hattrick-Simpers, Liyang Dai, Manfred Wuttig, Ichiro Takeuchi, Eckhard Quandt
Demonstration Of Magnetoelectric Scanning Probe Microscopy, Jason R. Hattrick-Simpers, Liyang Dai, Manfred Wuttig, Ichiro Takeuchi, Eckhard Quandt
Jason R. Hattrick-Simpers
A near-field room temperature scanning magnetic probe microscope has been developed using a laminated magnetoelectric sensor. The simple trilayer longitudinal-transverse mode sensor, fabricated using Metglas as the magnetostrictive layer and polyvinylidene fluoride as the piezoelectric layer, shows an ac field sensitivity of 467±3μV∕Oe in the measured frequency range of 200Hz–8kHz. The microscope was used to image a 2mm diameter ring carrying an ac current as low as 10−5A. ac fields as small as 3×10−10T have been detected.
An Infrared Imaging Method For High-Throughput Combinatorial Investigation Of Hydrogenation-Dehydrogenation And New Phase Formation Of Thin Films, H. Oguchi, Jason Hattrick-Simpers, I. Takeuchi, E. Heilweil, L. Bendersky
An Infrared Imaging Method For High-Throughput Combinatorial Investigation Of Hydrogenation-Dehydrogenation And New Phase Formation Of Thin Films, H. Oguchi, Jason Hattrick-Simpers, I. Takeuchi, E. Heilweil, L. Bendersky
Jason R. Hattrick-Simpers
We have developed an infrared imaging setup enabling in situ infrared images to be acquired, and expanded on capabilities of an infrared imaging as a high-throughput screening technique, determination of a critical thickness of a Pd capping layer which significantly blocks infrared emission from below, enhancement of sensitivity to hydrogenation and dehydrogenation by normalizing raw infrared intensity of a Mg thin film to an inert reference, rapid and systematic screening of hydrogenation and dehydrogenation properties of a Mg–Ni composition spread covered by a thickness gradient Pd capping layer, and detection of formation of a Mg2Si phase in a Mg thin …