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Relevant bibliographies by topics / Transition metal defect model

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Academic literature on the topic 'Transition metal defect model'

Author: Grafiati

Published: 4 June 2021

Last updated: 16 February 2022

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Journal articles on the topic "Transition metal defect model"

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Давыдов, С. Ю., and О. В. Посредник. "Барьер Шоттки на контакте магнитного 3d-металла с полупроводником." Письма в журнал технической физики 47, no. 11 (2021): 37. http://dx.doi.org/10.21883/pjtf.2021.11.51006.18650.

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With the aim of the Friedel transition metal d-band model and semiconductor local defect state model the analytical expressions for metal – semiconductor charge transfer and Schottky barrier height are obtained. It is shown that the account of metal magnetization leads to the increase of the charge transfer and corresponding contribution to the Schottky barrier height. Numerical estimates are made for the contacts of Co and Ni with 6H- and 4H-SiC polytypes.

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Bishop, A. R., J. Tinka Gammel, and S. R. Phillpot. "Ground and defect states in a two band model of halogen-bridged transition metal linear chain complexes." Synthetic Metals 29, no. 2-3 (March 1989): 151–59. http://dx.doi.org/10.1016/0379-6779(89)90893-x.

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Huu Kien, Pham. "Study of Structural and Phase Transition of Nickel Metal." ISRN Materials Science 2014 (March 9, 2014): 1–6. http://dx.doi.org/10.1155/2014/253627.

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Annealing study of nickel metal in the temperature range 300–1000 K has been carried out using molecular dynamics (MD) simulations. The simulation is done for models containing 104 particles Ni at both crystalline and amorphous states. We obtain the change as a function of annealing time for the potential energy of system, pair radial distribution function (PRDF), and distribution of coordination number (DCN). The calculation shows that the aging slightly reduces the potential energy of system. This result evidences that the amorphous model undergoes different quasiequilibrated states during annealing. The crystalline model undergoes the slow relaxation which reduces the energy of system and eliminates structural defects in crystal lattices.

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Christenson, Eric T., Dervla T. Isaac, Karin Yoshida, Erion Lipo, Jin-Sik Kim, Rodolfo Ghirlando, Ralph R. Isberg, and Anirban Banerjee. "The iron-regulated vacuolar Legionella pneumophila MavN protein is a transition-metal transporter." Proceedings of the National Academy of Sciences 116, no. 36 (August 20, 2019): 17775–85. http://dx.doi.org/10.1073/pnas.1902806116.

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Legionella pneumophila causes a potentially fatal form of pneumonia by replicating within macrophages in the Legionella-containing vacuole (LCV). Bacterial survival and proliferation within the LCV rely on hundreds of secreted effector proteins comprising high functional redundancy. The vacuolar membrane-localized MavN, hypothesized to support iron transport, is unique among effectors because loss-of-function mutations result in severe intracellular growth defects. We show here an iron starvation response by L. pneumophila after infection of macrophages that was prematurely induced in the absence of MavN, consistent with MavN granting access to limiting cellular iron stores. MavN cysteine accessibilities to a membrane-impermeant label were determined during macrophage infections, revealing a topological pattern supporting multipass membrane transporter models. Mutations to several highly conserved residues that can take part in metal recognition and transport resulted in defective intracellular growth. Purified MavN and mutant derivatives were directly tested for transporter activity after heterologous purification and liposome reconstitution. Proteoliposomes harboring MavN exhibited robust transport of Fe2+, with the severity of defect of most mutants closely mimicking the magnitude of defects during intracellular growth. Surprisingly, MavN was equivalently proficient at transporting Fe2+, Mn2+, Co2+, or Zn2+. Consequently, flooding infected cells with either Mn2+ or Zn2+ allowed collaboration with iron to enhance intracellular growth of L. pneumophila ΔmavN strains, indicating a clear role for MavN in transporting each of these ions. These findings reveal that MavN is a transition-metal-ion transporter that plays a critical role in response to iron limitation during Legionella infection.

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RENDULIC, K. D., and A. WINKLER. "THE INFLUENCE OF SURFACE DEFECTS AND FOREIGN ATOMS ON THE ADSORPTION KINETICS." International Journal of Modern Physics B 03, no. 07 (July 1989): 941–72. http://dx.doi.org/10.1142/s0217979289000701.

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We describe the influence of surface structure, surface steps, point defects and foreign atoms on the physics of adsorption and desorption. The investigations are performed on the model systems H 2- Ni and H 2- Pt as representatives of adsorption on transition metals and H 2- Cu as an example for adsorption on a noble metal. The energy variation of the sticking coefficient and the angular variation of the adsorption and desorption probability are used to characterize the different physical processes occurring during adsorption.

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Martin, M. "Trapping during hopping conduction of electronic defects: A conductivity model for doped transition metal oxides." Phys. Chem. Chem. Phys. 6, no. 13 (2004): 3627–32. http://dx.doi.org/10.1039/b402156h.

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Brown, Randall H., and A. E. Carlsson. "Effective pair interactions for a model binary transition metal alloy at point and extended defects." Solid State Communications 61, no. 12 (March 1987): 743–46. http://dx.doi.org/10.1016/0038-1098(87)90469-8.

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Hanzig, Juliane, Matthias Zschornak, Erik Mehner, Florian Hanzig, Sven Jachalke, Melanie Nentwich, Hartmut Stöcker, Tilmann Leisegang, Christian Röder, and Dirk Meyer. "Defect separation in strontium titanate: Formation of a polar phase." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C233. http://dx.doi.org/10.1107/s2053273314097666.

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Stoichiometric perovskite-type strontium titanate acts as an insulator because of its wide electronic band gap and has therefore great potential as high-k dielectric and storage material in memory applications. Degradation phenomena of insulating properties of transition metal oxides occur during long time voltage application. From the defect chemistry point of view the question arises how mobile species react on an external electric field and which impact the redistribution has on the stability of the crystal structure. Here, we discuss near-surface reversible structural changes in SrTiO3 single crystals caused by oxygen vacancy redistribution in an external electric field. We present in-situ X-ray diffraction during and after electroformation. Several reflections are monitored and show a tetragonal elongation of the cubic unit cell. Raman investigations were carried out to verify that the expansion involves a transition from the centrosymmetric to a less symmetric structure. Regarding a whole formation cycle, two different time scales occur: a slow one during the increase of the lattice constant and a fast one after switching off the electric field. Based on the experimental data we suggest a model containing the formation of a polar SrTiO3 unit cell stabilized by the electric field, which is referred to as migration-induced field-stabilized polar phase [1] at room temperature. As expected by a non-centrosymmetric crystal structure, pyroelectric properties will be presented in conjunction with temperature modulated electroformation cycles. Furthermore, we show that intrinsic defect separation establishes a non-equilibrium accompanied by an electromotive force. A comprehensive thermodynamic deduction in terms of theoretical energy and entropy calculations indicates an exergonic electrochemical reaction after the electric field is switched off. Based on that driving force the experimental and theoretical proof of concept of a solid-state SrTiO3 battery is reported.

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Сафиулина, И. А., Е. В. Алтынбаев, Е. Г. Яшина, A. Heinemann, Л. Н. Фомичева, А. В. Цвященко, and С. В. Григорьев. "Исследование мезоструктуры моногерманидов переходных металлов, синтезированных под давлением." Физика твердого тела 60, no. 4 (2018): 747. http://dx.doi.org/10.21883/ftt.2018.04.45687.236.

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AbstractThe mesostructure of transition-metal monogermanides Mn_1 – x Co_ x Ge is studied by small-angle neutron scattering in a wide range of concentrations x = 0–0.95. These compounds were synthesized under high pressure and are metastable under normal conditions. The experimental dependences I ( Q ) obtained for the whole series of samples in the range of transferred momenta (6 × 10^–2 nm^–1 < Q < 2.5 nm^–1) are described by the power dependence Q ^– n with an exponent n = 2.99 ± 0.02, uniquely related to the fractal properties of the system under study. The dependence obtained indicates that the superatomic structure of the samples is characterized by the presence of defects with a spatial organization described by a fractal model with a logarithmic dependence of the correlation function of the defect density. It is interesting to note that such defects are absent in the isostructural FeGe compound, i.e., the experimental dependences of the intensity are described well by the expression Q ^– n with an exponent n = 4.1 ± 0.1, which demonstrates the presence of crystallites with a uniform density distribution inside and a sharp boundary characterizing the surface.

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Kräuter, Jessica, Lars Mohrhusen, Tim Thiedemann, Michael Willms, and Katharina Al-Shamery. "Activation of Small Organic Molecules on Ti2+-Rich TiO2 Surfaces: Deoxygenation vs. C–C Coupling." Zeitschrift für Naturforschung A 74, no. 8 (August 27, 2019): 697–707. http://dx.doi.org/10.1515/zna-2019-0135.

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AbstractRutile TiO2 is an important model system for understanding the adsorption and conversion of molecules on transition metal oxide catalysts. In the last decades, point defects, such as oxygen vacancies and Ti3+ interstitials, exhibited an important influence on the reaction of oxygen and oxygen-containing molecules on titania surfaces. In brief, partially reduced TiO2 containing a significant amount of Ti3+ is often more active for the conversion of such molecules. In this study, we investigate an even higher reduced surface prepared by argon ion bombardment of a rutile TiO2 (110) single crystal. By X-ray photoelectron spectroscopy we show that, besides Ti4+, this surface is almost equally dominated by Ti3+ and Ti2+. To probe the reactivity of these highly reduced surfaces, we have adsorbed two different classes of oxygen-containing molecules and utilized temperature programmed reaction spectroscopy to investigate the conversion. While alcohols (in this case methanol) already show a defect-dependent partial conversion in a deoxygenation reaction on the (stochiometric or slightly reduced) rutile TiO2 (110) surface, ketones (e.g. acetone) are usually not converted on the rutile TiO2 (110) surface independent on the bulk defect density. Here, we present a nearly full conversion for both molecules via deoxygenation reactions and reductive C–C coupling, forming different hydrocarbons at different temperatures between 375 K and 640 K on the sputtered Ti2+ rich surface.

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Dissertations / Theses on the topic "Transition metal defect model"

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Ackland, G. J. "Non-pairwise potentials and defect modelling for transition metals." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379869.

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Andraud, Chantal. "Defauts d'empilement dans le materiau unidimensionnel cscdbr::(3) : etude spectroscopique." Paris 6, 1987. http://www.theses.fr/1987PA066140.

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L'etude des proprietes optiques de cscdbr::(3) a montre l'existence de centres br::(2)**(2-). L'excitation des echantillons par des rayonnements ionisants (rx, faisceau d'electrons) et des experiences d'absorption a deux photons ont permis d'associer les differentes bandes d'emission et d'absorption observees a des transitions appartenant a ces centres. L'existence de ces centres br::(2)**(2-) est attribuee a la presence de defauts d'empilement. L'effet d'une pression hydrostatique, le dopage par des ions pb**(2x) et le recuit des cristaux confirment l'hypothese

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Bogaert, Kevin Christopher. "Defect-driven processing of two-dimensional transition metal dichalcogenides." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/122072.

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This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2019
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 149-161).
Two-dimensional transition metal dichalcogenides (TMDs) are an emerging class of semiconductor materials that offer exciting new properties for future electronic and optoelectronic applications. However, many ongoing challenges related to synthesis and processing must be overcome before this nascent technology can become industrially viable. In this thesis, processing-related phenomena relevant to the fabrication of TMD heterostructures, alloys, and nanoporous membranes are presented. This thesis begins with an investigation of the role of substrate temperature in two-step chemical vapor deposition (CVD) growth of MoS₂/WS₂ heterostructures. We demonstrate diffusion-mediated synthesis of inverted lateral heterostructures following low MoS2 growth temperatures in the second CVD step and homogeneous Mo[subscript x]W[subscript 1-x]S₂ alloyed crystals following higher MoS₂ growth temperatures.
Investigating the nature of this diffusion-mediated process, we identify an energetically favorable atomistic model proposing that transition metal diffusion is driven by a heterogeneous distribution of sulfur vacancies. This model is corroborated by the synthesis of a composition-graded Mo[subscript x]W[subscript 1-x]S₂ alloy crystals in which the final-stage spatial distribution of transition metal atoms correlates with intermediate-stage distribution of point defects. These heterogeneous crystals allow for correlation of the local optical properties with the local composition, demonstrating a variation in photoluminescence intensity spanning two orders of magnitude and reaching the maximum value for equicompositional alloy Mo₀.₅W₀.₅S₂ (x=0.5). Furthermore, the correlation between intermediate-stage distribution of point defects and final-stage spatial distribution of transition metal atoms enables the opportunity for bespoke patterning.
Utilizing a laser annealing technique, we demonstrate the ability to locally induce defects that define the regions of preferential nucleation during subsequent CVD growth. Finally, defect processing is also demonstrated in nanoporous TMD membrane applications. Combining modeling with experimentation, we demonstrate the relationship between vacuum annealing time and temperature with nanopore properties such as average radius and edge structure. Control of these properties is essential for the fabrication of functional nanoporous membrane devices for sensing, filtration, and energy applications. This thesis motivates further work on TMD processing in pursuit of developing a fundamental understanding of the defect-driven diffusion mechanism, a larger library of interesting TMD compositions and structures, as well as industrially viable TMD devices.
by Kevin Christopher Bogaert.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Materials Science and Engineering

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Paul, Marcus. "Synthesis and characterisation of transition metal-doped lithium niobate and lithium tantalate." Thesis, University of Aberdeen, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319341.

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The study of ferroelectric LiNbO₃ and LiTaO₃ doped with transition metals involves the characterisation of LiNbO₃/LiTaO₃ solid solutions in the systems Li₂O-Nb₂O₅-M_xO_y and Li₂O-Ta₂O₅-M_xO_y (M = Cr, Mn, Fe, Co, Ni, Cu). Compounds were made by solid state reaction at temperatures between 1000 and 1500°C, depending on the system studied. The emphasis of this work is on the characterisation of the defect structure of LiNbO₃/LiTaO₃ solid solutions using phase diagram determination, X-ray and neutron powder diffraction, EXAFS, ESR and optical spectroscopy. The valence of the incorporated cations was studied by magnetic measurements. The electrical properties of these materials have been investigated using AC impedance spectroscopy. It can be shown that the physical properties of LiNbO₃ and LiTaO₃ depend strongly on the defects in the structure which can be controlled by purposeful doping with other cations. Structural refinements of the X-ray and neutron powder diffraction data have shown that the defects arising from nonstoichiometry are accommodated by vacancies created on the Li site. This affects the structure when doped with third cations, giving rise to complex substitution mechanisms Spectroscopic studies have shown that the dopants (Cr³⁺, Mn²⁺/Mn³⁺, Co²⁺, Ni²⁺, Cu⁺, Cu²⁺) are shifted from the central octahedral position towards the adjacent empty octahedron. The electrical properties of LiNbO₃ and LiTaO₃, measured by AC impedance spectroscopy, depend strongly on the dopant content: the conductivity generally rises, whereas the activation energy for the electrical conductivity drops with increasing dopant concentration. The microstructure of electroceramics can also be probed by AC impedance spectroscopy and it was shown that the texture of all samples was bad due to poor sintering of the pellets. Longer sintering times did not improve the quality of the ceramics which exhibit a large pore size distribution. An important aspect for future work would be the quality improvement of LiNbO₃/LiTaO₃ based ceramics.

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Kummari, Venkata Chandra Sekhar. "A New Approach for Transition Metal Free Magnetic Sic: Defect Induced Magnetism After Self-ion Implantation." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc271849/.

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SiC has become an attractive wide bandgap semiconductor due to its unique physical and electronic properties and is widely used in high temperature, high frequency, high power and radiation resistant applications. SiC has been used as an alternative to Si in harsh environments such as in the oil industry, nuclear power systems, aeronautical, and space applications. SiC is also known for its polytypism and among them 3C-SiC, 4H-SiC and 6H-SiC are the most common polytypes used for research purposes. Among these polytypes 4H-SiC is gaining importance due to its easy commercial availability with a large bandgap of 3.26 eV at room temperature. Controlled creation of defects in materials is an approach to modify the electronic properties in a way that new functionality may result. SiC is a promising candidate for defect-induced magnetism on which spintronic devices could be developed. The defects considered are of room temperature stable vacancy types, eliminating the need for magnetic impurities, which easily diffuse at room temperature. Impurity free vacancy type defects can be created by implanting the host atoms of silicon or carbon. The implantation fluence determines the defect density, which is a critical parameter for defect induced magnetism. Therefore, we have studied the influence of low fluence low energy silicon and carbon implantation on the creation of defects in n-type 4H-SiC. The characterization of the defects in these implanted samples was performed using the techniques, RBS-channeling and Raman spectroscopy. We have also utilized these characterization techniques to analyze defects created in much deeper layers of the SiC due to implantation of high energy nitrogen ions. The experimentally determined depths of the Si damage peaks due to low energy (60 keV) Si and C ions with low fluences (< 1015 cm-2) are consistent with the SRIM-2011 simulations. From RBS-C Si sub-lattice measurements for different fluences (1.1×1014 cm-2 to 3.2×1014 cm-2) of Si implantation in 4H-SiC, the Si vacancy density is estimated to range from 1.29×1022 cm-3 to 4.57×1022 cm-2, corresponding to average vacancy distances of 4.26 Å to 2.79 Å at the damage peak (50±5 nm). Similarly, for C implanted fluences (1.85×1014 cm-2 to 1×1015 cm-2), the Si vacancy density varies from 1.37×1022 cm-3 to 4.22×1022 cm-3 with the average vacancy distances from 4.17 Å to 2.87 Å at the damage peak (110±10 nm). From the Raman spectroscopy, the implantation-induced lattice disorders calculated along the c-axis (LO mode) and perpendicular to c-axis (TO mode) in 4H-SiC are found to be similar. Furthermore, the results obtained from SQUID measurements in C implanted n-type 4H-SiC sample with fluences ranging from 1×1012 to 1.7×1016 ions/cm2 have been discussed. The implanted samples showed diamagnetism similar to the unimplanted sample. To date, to our best of knowledge, no experimental work has been reported on investigating defect induced magnetism for self-ion implantation in n-type 4H-SiC. These first reports of experimental results can provide useful information in future studies for a better understanding of self-ion implantation in SiC-based DMS.

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Schmid, John Robert 1952. "A model for estimating allowable transition metal contamination in DRAMs." Thesis, The University of Arizona, 1993. http://hdl.handle.net/10150/291463.

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Due to new memory-cell architectures, the leakage-current requirements for semiconductor memories will become less stringent with increased levels of integration. The implication of these requirements with regard to allowable metallic contamination levels is investigated with a one-dimensional model based on Shockley-Read-Hall generation-recombination. The model was developed to predict leakage-current in carrier-depleted regions as a function of basic process and metallic contaminant parameters. As device dimensions are reduced, transition metal homogeneous contamination in process chemicals can be an important source of generation-recombination centers that result in the dominant generation-current in the space-charge region. The model allows an estimation of an upper bound for transition metal contamination in advanced processes and is applied for DRAM leakage predictions. Using the model, it is demonstrated that the trend toward lower leakage-current density requirements reverses after the 64-Mbit generation DRAM as a result of memory-cell architecture trends which significantly reduce the space-charge volume.

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Petzold, Stefan [Verfasser], Lambert [Akademischer Betreuer] Alff, and Leopoldo [Akademischer Betreuer] Molina-Luna. "Defect Engineering in Transition Metal Oxide-based Resistive Random Access Memory / Stefan Petzold ; Lambert Alff, Leopoldo Molina-Luna." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2020. http://d-nb.info/1204200912/34.

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Khalajzadeh, Vahid. "Modeling of shrinkage porosity defect formation during alloy solidification." Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6155.

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Among all casting defects, shrinkage porosities could significantly reduce the strength of metal parts. As several critical components in aerospace and automotive industries are manufactured through casting processes, ensuring these parts are free of defects and are structurally sound is an important issue. This study investigates the formation of shrinkage-related defects in alloy solidification. To have a better understanding about the defect formation mechanisms, three sets of experimental studies were performed. In the first experiment, a real-time video radiography technique is used for the observation of pore nucleation and growth in a wedge-shaped A356 aluminum casting. An image-processing technique is developed to quantify the amount of through-thickness porosity observed in the real-time radiographic video. Experimental results reveal that the formation of shrinkage porosity in castings has two stages: 1-surface sink formation and 2- internal porosity evolution. The transition from surface sink to internal porosity is defined by a critical coherency limit of . In the second and third experimental sets, two Manganese-Steel (Mn-Steel) castings with different geometries are selected. Several thermocouples are placed at different locations in the sand molds and castings to capture the cooling of different parts during solidification. At the end of solidification, castings are sectioned to observe the porosity distributions on the cut surfaces. To develop alloys’ thermo-physical properties, MAGMAsoft (a casting simulation software package) is used for the thermal simulations. To assure that the thermal simulations are accurate, the properties are adjusted to get a good agreement between simulated and measured temperatures by thermocouples. Based on the knowledge obtained from the experimental observations, a mathematical model is developed for the prediction of shrinkage porosity in castings. The model, called “advanced feeding model”, includes 3D multi-phase continuity, momentum and pore growth rate equations which inputs the material properties and transient temperature fields, and outputs the feeding velocity, liquid pressure and porosity distributions in castings. To solve the model equations, a computational code with a finite-volume approach is developed for the flow calculations. To validate the model, predicted results are compared with the experimental data. The comparison results show that the advanced feeding model can accurately predict the occurrence of shrinkage porosity defects in metal castings. Finally, the model is optimized by performing several parametric studies on the model variables.

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Suntivich, Jin. "Interplay between electronic structure and catalytic activity in transition metal oxide model system." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/76134.

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Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 109-125).
The efficiency of many energy storage and conversion technologies, such as hydrogen fuel cells, rechargeable metal-air batteries, and hydrogen production from water splitting, is limited by the slow kinetics of the oxygen electrochemical reactions. Transition-metal oxides can exhibit high catalytic activity for oxygen electrochemical reactions, which can be used to improve efficiency and cost of these devices. Identifying a catalyst "design principle" that links material properties to the catalytic activity can accelerate the development of highly active, abundant transition metal oxide catalysts fore more efficient, cost-effective energy storage and conversion system. In this thesis, we demonstrate that the oxygen electrocatalytic activity for perovskite transition metal oxide catalysts primarily correlates to the a* orbital ("eg") occupation. We further find that the extent of B-site transition metal-oxygen covalency can serve as a secondary activity descriptor. We hypothesize that this correlation reflects the critical influences of the a* orbital and transition metal-oxygen covalency on the ability of the surface to displace and stabilize oxygen-species on surface transition metals. We further propose that this ability to stabilize oxygen-species reflect as the rate-limiting steps of the oxygen electrochemical reactions on the perovskite oxide surfaces, and thus highlight the importance of electronic structure in controlling the oxide catalytic activity.
by Jin Suntivich.
Sc.D.

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Sawant, Ronit Prasad. "COMSOL Multi-physics model for Transition Metal Dichalcogenides (TMD’s)-Nafion composite Based Electromechanical Actuators." Digital WPI, 2018. https://digitalcommons.wpi.edu/etd-theses/1261.

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The ability to convert electrical energy into mechanical motion is of significant interest in many energy conversion technologies. For more than a decade Ionic polymer-metal composite (IPMC) as an electroactive smart polymer material has been extensively studied and has shown great potential as soft robotic actuators, artificial muscles and dynamic sensors in the micro-to-macro size range. IPMC consists of an ion exchange polymer membrane sandwiched between two noble metal electrodes on either side of the membrane. Under applied potential, the IPMC actuator results in bending deformation because of ion migration and redistribution across its surface due to the imposed voltage. Nafion are highly porous polymer materials which have been extensively studied as the ion exchange membrane in IPMC. Nafion has also been mixed with carbon nanotubes, graphene, and metallic nanoparticles to improve actuation and bending characteristics of electro-mechanical actuators. For the first time, liquid phase exfoliated Transition Metal Dichalcogenides (TMDs)-Nafion nanocomposite based electro-mechanical actuators has been studied and demonstrate the improvement in the electromechanical actuation performance. In this thesis, we create a 2D model of the TMD-Nafion based electromechanical actuator in COMSOL Multi-physics software. The behavior of the model is examined at different electric potentials, frequencies, and actuation lengths. The simulation results were compared with the experimental data for validation of the model. The data showed improvement in the actuation for TMD-Nafion actuator when compared with pure Nafion actuator. The improvement in the actuation was due to the increase in diffusivity of the TMD-Nafion actuator in comparison with pure Nafion actuator. This increase in the diffusivity as seen in the model is because of the new proton conducting pathways being established with the addition of TMDs. The model also shows an increase in the stress and strain values with the incorporation of TMDs. With the same length of the actuator we were able to obtain more stress and strain with the addition of TMDs. This helps in improving the performance of the actuator as it would be able to handle more stress cycles which also increases the life of the actuator.

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Books on the topic "Transition metal defect model"

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1953-, Fujimori A., Tokura Y. 1954-, and Taniguchi International Symposium on the Theory of Condensed Matter (17th : 1994 : Kashikojima, Japan), eds. Spectroscopy of mott insulators and correlated metals: Proceedings of the 17th Taniguchi Symposium, Kashikojima, Japan, October 24-28, 1994. Berlin: Springer, 1995.

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Fujimori, Atsushi, and Yoshinori Tokura. Spectroscopy of Mott Insulators and Correlated Metals: Proceedings of the 17th Taniguchi Symposium, Kashikojima, Japan, October 24 - 28, 1994 (Springer Series in Solid-State Sciences). Springer, 1995.

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Book chapters on the topic "Transition metal defect model"

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Dubinin, N. E., L. D. Son, and N. A. Vatolin. "Thermodynamic Properties of Liquid Binary Transition-Metal Alloys in the Bretonnet-Silbert Model." In Defect and Diffusion Forum, 105–10. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/3-908451-35-3.105.

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Schmidt, Harald, Günter Borchardt, S. Weber, and Hubert Scherrer. "Diffusion in Transition Metal Diborides - An Overview." In Defect and Diffusion Forum, 219–24. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/3-908451-35-3.219.

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Jong, A. M., J. C. Muijsers, Th Weber, L. J. Ijzendoorn, V. H. J. Beer, J. A. R. Veen, and J. W. Niemantsverdriet. "Preparation, Structure and Surface Chemical Properties of Hydrotreating Model Catalysts: A Surface Science Approach." In Transition Metal Sulphides, 207–34. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-3577-3_9.

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Tomlinson, S. M., C. R. A. Catlow, and J. H. Harding. "Defect Clustering In Rock-Salt Structured Transition Metal Oxides." In Transport in Nonstoichiometric Compounds, 539–50. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2519-2_41.

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Capshew, C. E. "Commercialization of Olefin Polymerization Catalysts: Model for Success." In Handbook of Transition Metal Polymerization Catalysts, 113–29. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2010. http://dx.doi.org/10.1002/9780470504437.ch5.

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Zacher, M. G., A. Dorneich, C. Gröber, R. Eder, and W. Hanke. "The Metal-Insulator Transition in the Hubbard Model." In High Performance Computing in Science and Engineering ’99, 130–48. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/978-3-642-59686-5_12.

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Anda, E. V. "The Metal Insulator Transition in the Hubbard Model." In NATO ASI Series, 377–83. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4899-1042-4_42.

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Dohn, Asmus Ougaard. "Treating Relativistic Effects in Transition Metal Complexes." In Transient Changes in Molecular Geometries and How to Model Them, 23–36. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-18747-1_3.

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Novion, C. H., B. Beuneu, T. Priem, N. Lorenzelli, and A. Finel. "Defect Structures and Order-Disorder Transformations in Transition Metal Carbides and Nitrides." In The Physics and Chemistry of Carbides, Nitrides and Borides, 329–55. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-2101-6_20.

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Tabor, Christopher, Radha Narayanan, and Mostafa A. El-Sayed. "Catalysis with Transition Metal Nanoparticles in Colloidal Solution: Heterogeneous or Homogeneous?" In Model Systems in Catalysis, 395–414. New York, NY: Springer New York, 2009. http://dx.doi.org/10.1007/978-0-387-98049-2_18.

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Conference papers on the topic "Transition metal defect model"

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Jeong, Mun Seok. "Exploring defect-induced Raman mode of transition metal dichalcogenides monolayer using tip-enhanced resonance Raman spectroscopy." In Enhanced Spectroscopies and Nanoimaging 2020, edited by Prabhat Verma and Yung Doug Suh. SPIE, 2020. http://dx.doi.org/10.1117/12.2567945.

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Feng, Shaw C., Tesfaye Moges, and Paul W. Witherell. "Functional Requirements of Data Analytic Tools and Software for Metal Additive Manufacturing." In ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-24117.

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Abstract:

Abstract Additive manufacturing’s (AM’s) transition to an accepted production technology has led to increasing demands on data requirements. Many of these advances have been made possible by an increase in in-situ sensing and ex-situ measurement devices. These new devices are rapidly increasing the volume, variety, and value of AM data. The number of software tools used to measure, model, simulate, and manage AM material, part, and process is increasing to take advantage of emerging customer needs and market opportunities. However, the capabilities and accessibility of these tools, which are being used by both practitioners and researchers, vary greatly. Software tools for AM users should be able to handle ex-situ needs as well as address emerging in-situ requirements, including 1) process the different types of measured data, 2) understand defect formation, geometric variation, surface roughness, and 3) run fast enough for the layer-by-layer, scanning process. To better understand both the current capabilities and future needs, this paper provides an AM product-lifecycle landscape of software tools. The landscape includes tools for product design, design analysis, process planning, process monitoring, process modeling, process simulation, and production management. A preliminary set of functional requirements are identified, and requirements that if supported will further data analytics capabilities in AM. Furthermore, this paper identifies opportunities to develop new data-analytics tools that can improve product quality and reduce production time.

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Ahn, Hyeyoung, and Guan-Hua Lee. "Efficient defect healing of transition metal dichalcogenides by phthalocyanines." In 2D Photonic Materials and Devices II, edited by Arka Majumdar, Carlos M. Torres, and Hui Deng. SPIE, 2019. http://dx.doi.org/10.1117/12.2506867.

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Cheng, Wu-Tung, Brady Benware, Ruifeng Guo, Kun-Han Tsai, Takeo Kobayashi, Kazuyuki Maruo, Michinobu Nakao, Yoshiaki Fukui, and Hideyuki Otake. "Enhancing Transition Fault Model for Delay Defect Diagnosis." In 2008 17th Asian Test Symposium (ATS). IEEE, 2008. http://dx.doi.org/10.1109/ats.2008.44.

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Chen, Ying-Yu, Zelei Sun, and Deming Chen. "A SPICE model of flexible transition metal dichalcogenide field-effect transistors." In DAC '15: The 52nd Annual Design Automation Conference 2015. New York, NY, USA: ACM, 2015. http://dx.doi.org/10.1145/2744769.2744782.

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Bendler, J. T., J. J. Fontanella, M. F. Shlesinger, M. C. Wintersgill, Michio Tokuyama, Irwin Oppenheim, and Hideya Nishiyama. "The Defect Diffusion Model, Glass Transition and the Properties of Glass-Forming Liquids." In COMPLEX SYSTEMS: 5th International Workshop on Complex Systems. AIP, 2008. http://dx.doi.org/10.1063/1.2897787.

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Jongsawat, Nipat, and Wichian Premchaiswadi. "Developing a Bayesian Network Model Based on a State and Transition Model for Software Defect Detection." In 2012 13th ACIS International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel & Distributed Computing (SNPD). IEEE, 2012. http://dx.doi.org/10.1109/snpd.2012.41.

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Dmitrieva, Ludmila A., Yuri A. Kuperin, and German E. Rudin. "Mathematical model and design of nanoeloctronic device based on metal-dielectric transition." In Days on Diffraction 2007. IEEE, 2007. http://dx.doi.org/10.1109/dd.2007.4531986.

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Wu, Jixuan, Zhiqiang Fan, Jiezhi Chen, and Xiangwei Jiang. "A study on W vacancy defect in mono-layer transition-metal dichalcogenide (TMD) TFETs through systematic ab initio calculations." In 2017 Silicon Nanoelectronics Workshop (SNW). IEEE, 2017. http://dx.doi.org/10.23919/snw.2017.8242271.

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Brunthaler, G., and T. Hörmann. "Trap Model for the Metal-Insulator Transition in two-dimensional Si-MOS structures." In PHYSICS OF SEMICONDUCTORS: 28th International Conference on the Physics of Semiconductors - ICPS 2006. AIP, 2007. http://dx.doi.org/10.1063/1.2729832.

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Reports on the topic "Transition metal defect model"

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Jarrold, Caroline, and Krishnan Raghavachari. Probing catalytic activity in defect sites in transition metal oxides and sulfides using cluster models: A combined experimental and theoretical approach. Office of Scientific and Technical Information (OSTI), December 2019. http://dx.doi.org/10.2172/1580109.

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