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Hamilton, Craig D. "Density functional calculations of organometallic complexes containing metal-metal multiple bonds /". The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487950153600457.
Pełny tekst źródłaMcAllister, B. P. "A density functional theory study of reactions of metal and metal oxides". Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426760.
Pełny tekst źródłaLouca, P. "From X-ray structure factors to electron-density distributions". Thesis, University of Bristol, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374638.
Pełny tekst źródłaRemenyi, Christian. "Density functional studies on EPR parameters and spin-density distributions of transition metal complexes". Doctoral thesis, [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=982187890.
Pełny tekst źródłaRavetz, Megan Sarah. "Effect metal electron density on C-H activation reactions". Thesis, University of Salford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360458.
Pełny tekst źródłaBurrill, Daniel. "Density Functional Theory Study of Dilute Transition Metal Phthalocyanines". ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/508.
Pełny tekst źródłaZhuang, Houlong. "First-principles studies of metal-carbon nanotube systems". Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B39395789.
Pełny tekst źródłaZhuang, Houlong, i 庄厚龍. "First-principles studies of metal-carbon nanotube systems". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39395789.
Pełny tekst źródłaWang, Jiaqi. "Transition Metal Catalyzed Oxidative Cleavage of C-O Bond". Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc801914/.
Pełny tekst źródłaBansal, Shubhra. "Characterization of Nanostructured Metals and Metal Nanowires for Ultra-High Density Chip-to-Package Interconnections". Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14041.
Pełny tekst źródłaDurr, Christopher Blair. "The Effect of Metal Containing Ligands on The Metal-Metal Quadruple Bond: Structure, Synthesis, And Photophysics". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429542171.
Pełny tekst źródłaSadjadi, Seyedabdolreza. "Ab initio relativistic-consistent calculations and charge density and experimental mass-spectroscopic analysis of mono and poly-nuclearclusters of group 11 and 12 transition metals and metal chlorides: ySeyedabdolreza Sadjadi". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B5060577X.
Pełny tekst źródłapublished_or_final_version
Chemistry
Doctoral
Doctor of Philosophy
Durivage, Jason Curtis. "Ligand Effects on Metal-Metal Bonding: Photoelectron Spectroscopy and Electronic Structure Calculations of Dimetal Paddlewheel Complexes". Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/145427.
Pełny tekst źródłaDang, Li. "Density functional theory studies of copper(I) mediated borylation and carboxylation reactions /". View abstract or full-text, 2010. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202010%20DANG.
Pełny tekst źródłaCrabtree, Elaine. "The role of metal ions in LDL peroxidation". Thesis, Birkbeck (University of London), 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266211.
Pełny tekst źródłaWang, Jiaqi. "The Impact of Computational Methods on Transition Metal-containing Species". Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc822795/.
Pełny tekst źródłaTang, Miru. "DENSITY FUNCTIONAL THEORY STUDIES ON THE STRUCTURE AND CATALYTIC ACTIVITY OF METAL OXIDES". OpenSIUC, 2018. https://opensiuc.lib.siu.edu/dissertations/1602.
Pełny tekst źródła唐素明 i So-ming Glenna Tong. "Theoretical studies of transition metal containing diatomics and DNA electron transfer". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31244828.
Pełny tekst źródłaSchiros, Theanne. "Water-Metal Surfaces : Insights from core-level spectroscopy and density functional theory". Doctoral thesis, Stockholm University, Department of Physics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7435.
Pełny tekst źródłaComputational methods are combined with synchrotron-based techniques to analyze the structure and bonding of water and water plus hydroxyl at metal surfaces under UHV and at near-ambient conditions. Water-metal interaction plays a crucial role in a multitude of cosmic, atmospheric and biological phenomena as well as heterogeneous catalysis, electrochemistry and corrosion. A spotlight of renewed interest has recently been cast on water-metal systems due to their relevance for surface chemical reactions related to the production and utilization of hydrogen as a clean energy carrier. In particular, H2O and OH are essential reaction intermediates in the renewable production of hydrogen from sunlight and water and in fuel cell electrocatalysis.
Fuel cells are considered one of the most promising power generation technologies for a sustainable energy future. A mechanistic understanding of the oxygen reduction reaction (ORR) pathway, including the role of electronic and geometric structure of the catalyst, is essential to the design of more efficient fuel cell catalysts. This is intimately connected to fundamental factors that affect the ability to form water-metal bonds as well as the site occupation and orientation of the adsorbed H2O and OH at active metal surfaces.
Key relationships related to critical issues in the fuel cell reaction are illuminated by the synergy of theory and experiment in this thesis. We emerge with a detailed understanding of the structure of the water-metal interface and the factors that rule the wettability of a metal surface, including geometric and electronic structure effects and the influence of coadsorbed species. We show that the preferred microscopic orientation of the water monolayer has consequences for macroscopic properties, and reveal the origin of the hydrophobic water layer. Finally, we identify a cooperativity effect that drives the stability of the mixed water/hydroxyl layer at metal surfaces, an important ORR intermediate.
Wedberg, Dan. "Dislocation density based material model applied in FE-simulation of metal cutting". Licentiate thesis, Luleå tekniska universitet, Material- och solidmekanik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26278.
Pełny tekst źródłaGodkänd; 2010; 20100809 (danwed); LICENTIATSEMINARIUM Ämnesområde: Materialmekanik/Material Mechanics Examinator: Professor Lars-Erik Lindgren, Luleå tekniska universitet Diskutant: Professor Bevis Hutchinson, Swerea KIMAB, Stockholm Tid: Torsdag den 23 september 2010 kl 10.00 Plats: E246, Luleå tekniska universitet
Martin, Lara J. "Study on metal adhesion mechanisms in high density interconnect printed circuit boards". Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/19628.
Pełny tekst źródłaLamb, David J. "The oxidation of low density lipoprotein by cells and transition metal ions". Thesis, University of Reading, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358450.
Pełny tekst źródłaEaglesham, D. J. "Charge density waves and their phase transitions in the transition metal chalcogenides". Thesis, University of Bristol, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375017.
Pełny tekst źródłaPardue, Daniel B. "Computational Studies of C–H/C–C Manipulation Utilizing Transition Metal Complexes". Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc801892/.
Pełny tekst źródłaPaget, Veronica J. "The modelling of transition metal centres using molecular mechanics and density functional theory". Thesis, University of Bath, 1996. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320428.
Pełny tekst źródłaKirichenko, E., i E. Belovol. "High-energy-density sugar biobattery". Thesis, Sumy State University, 2014. http://essuir.sumdu.edu.ua/handle/123456789/45213.
Pełny tekst źródłaMalliakas, Christos D. "Charge density waves and structural modulations in polytelluride compounds". Diss., Connect to online resource - MSU authorized users, 2007.
Znajdź pełny tekst źródłaOlaoye, Olufemi Opeyemi. "Density functional calculation of simple molecules". Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20345.
Pełny tekst źródłaAFRIKAANSE OPSOMMING: Berekeninge met Density Functional Theory (DFT) is ’n nuttige tegniek om die dinamika van molekules op potensiële energievlakke te verstaan. Beginnende met ’n prototipe molekuul formaldimien, wat die kern vorm van die groter fotochromiese molekuul dithizonatophenyl kwik (DPM), word die modellering van die molekuul meer ingewikkeld tot laasgenoemde bestudeer kan word asook sy fotochromiese afgeleides wat vervanging van elektronryk en elektronarm radikale by orto, meta en para posisies van die phenyl ringe insluit. DFT berekeninge word met spektra van Absorpsiespektroskopie met UV en sigbare lig asook tyd opgeloste spektra, verkry dmv femtosekondespektroskopie, vergelyk. In pol^ere aprotiese, pol^ere protiese en nie-pol^ere oplosmiddels, isomeriseer die molekuul om die C=N dubbelbinding. Daar kan tussen die twee isomere onderskei word deur dat die een in oplossing in sy grondtoestand blou en die ander een oranje voorkom. Die isomerisering is’n fotogeinduseerde proses. Die optimering van die molekul^ere struktuur, absorpsiespektra, oplosmiddel-afhanklikheid, en potensiële energievlak metings van die molekuul word bestudeer. Die sterk/swak wisselwerking wat in pol^ere protiese/aprotiese oplosmiddels verskyn word geopenbaar deur die hoe/lae absorpsie van die sekond^ere bande van die molekules. Daar is gevind dat die absorpsiespektra van DPM bathochromies in oplosmiddels met hoë diëlektriese konstantes is. Vir die potensiële energievlak berekeninge van die grondtoestand word rigiede en ontspanne metodes gebruik waar laasgenoemde met gebroke simmetrie berekeninge verkry word. Van alle metodes wat vir berekeninge gebruik was, gee die B3LYP/CEP-31G metode die beste benadering aan eksperimentele data. Alle berekeninge word gedoen met twee bekende sagteware pakkette; Amsterdam Density Functional (ADF) en Gaussian, wat op twee verskillende DFT metodes gebaseer is.
ENGLISH ABSTRACT: Density functional theory is a useful computational tool in the understanding of molecular dynamics on potential energy surfaces. Starting with a prototype molecule formaldimine, the photochromic molecule dithizonatophenylmercury II (DPM) and a set of its photochromic derivatives, (involving substitutions of electron donating and electron withdrawing substituents at ortho, meta and para positions of the dithizonato phenyl rings), are studied through density functional calculation in comparison with steady state absorption spectra obtained from UV-Visible and femto second spectroscopy experiments. In polar aprotic, polar protic and non-polar solvents these molecules isomerise around C=N double bond chromophore, from orange electronic ground states to blue electronic ground states upon photo-excitation. We investigate the structural optimisations, the absorption spectra, the solvent dependence and the potential energy surface (PES) of these molecules. The strong (weak) interactions exhibited by the polar protic (aprotic) solvents used are revealed through high (low) absorbance in the secondary bands of these molecules. The absorption spectra of DPM are found to be bathochromic in solvents with high dielectric constants. For the ground state PES calculation we make use of rigid and relaxed methods, and the latter is obtained through broken symmetry calculation. Of all the methods used in calculation, B3LYP/CEP-31G method gives the best approximation to the experimental data. All calculations are done using the two renown software, Amsterdam Density Functional (ADF) and Gaussian, availing their different density functional methods.
Zhang, Yuhan. "POLYMER ELECTROLYTES FOR HIGH CURRENT DENSITY LITHIUM STRIPPING/PLATING TEST". University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1555090752890092.
Pełny tekst źródłaMoynihan, Randall H. "The flow stability of linear low-density polyethlene at polymer and metal interfaces". Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-07132007-143144/.
Pełny tekst źródłaLynch, Mark Francis. "Chemical reactions of small molecules on metal surfaces : a density functional theory study". Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314017.
Pełny tekst źródłaElliott, J. D. "The application of linear-scaling Density Functional Theory to large metal oxide nanotubes". Thesis, University of Liverpool, 2016. http://livrepository.liverpool.ac.uk/3003340/.
Pełny tekst źródłaHagiya, Toru. "Electronic Excitation and Density Response in Liquid Alkali Metals Studied by Inelastic X-ray Scattering". Kyoto University, 2020. http://hdl.handle.net/2433/253075.
Pełny tekst źródłaRitschel, Tobias. "Electronic self-organization in layered transition metal dichalcogenides". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-188265.
Pełny tekst źródłaD'Acchioli, Jason S. "On the nature of the electronics structure of metal-metal quadruply bonded complexes". Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1126621699.
Pełny tekst źródłaTitle from first page of PDF file. Document formatted into pages; contains xii, 286 p.; also includes graphics (some col.). Includes bibliographical references (p. 273-286). Available online via OhioLINK's ETD Center
Venter, Gerhard (Gerhard Abraham). "An Ab Initio density functional study of the structure and stability of transition metal ozone complexes". Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52650.
Pełny tekst źródłaENGLISH ABSTRACT: A thorough search through the literature as well as through the Cambridge Crystallographic Structural Database resulted in no examples of a neutral ozone acting as ligand in a complex with any metal. Ionic compounds containing ozonide as anionic species, however, are well known throughout the literature and not surprisingly the only result for 0₃ and a metal in the CCSD was an ionic rubidium ozonide compound. What follows is a systematic study into the result of placing an ozone ligand within complexing distance of a transition metal (the first transition row from titanium to copper). Due to the novelty of the system, as first approximation four different orientations of the ozone ligand relative to the metal (a metal cation in these calculations) were investigated. It was found that coordination through the terminal oxygens resulted in energy minima for all the metal cations, although not necessarily the absolute energy minimum on the potential energy surface for the specific cation. A further structural study was done by adding carbonyl and hydrogen ligands to the system, according to the 18-electron rule. For these calculations coordination through the terminal oxygens was employed. In both series the dissociation energy was also calculated. The dissociation energies for the M(CO)nHm(0₃) complexes were all positive, indicating that they are theoretically stable structures. The resulting wave functions were then analysed with the help of three techniques: Atoms in Molecules (AIM), Charge Decomposition Analysis (CDA) and Natural Bond Orbital Analysis (NBO). AIM showed that bonds were indeed formed between the ozone ligand and the transition metal and hinted that the bonding model can be interpreted with the Dewar-Chatt-Duncanson (DCD) model of σ-donation and л-back donation. CDA confirmed that this was the case. NBO results proved erroneous due to the largely delocalized electronic structure of the complexes.
AFRIKAANSE OPSOMMING: 'n Deeglike soektog deur die literatuur en die Cambridge Crystallographic Structural Database het geen resultate gelewer van komplekse waarin 'n neutrale osoonligand komplekseer met 'n metaal nie. Ioniese verbindings waarin die osonied as anioon optree, is wel bekend deur die literatuur en die enigste resultaat in die CCSD - vir 'n soektog bevattende osoon en 'n metaal - het 'n rubidiumosonied-verbinding opgelewer. Wat volg is 'n stelselmatige studie om die effek te ondersoek indien 'n osoonligand naby genoeg aan 'n oorgangsmetaal geplaas word om kompleksering te bevoordeel (metale wat gebruik is, is die eerste oorgangsreeks vanaf titanium tot koper). As gevolg van die onbekendheid van die sisteem is vier verskillende oriëntasies van die osoonligand relatied tot die metal ('n metal katioon in die geval) as beginpunt ondersoek. Daar is gevind dat koordinasie deur die terminale suurstowwe van die osoonligand vir al die metal katione lei tot energie minima, alhoewel dié minima nie noodwendig die globale minima op die potensiële energie oppervlaktes van die katione is nie. 'n Verdere studie is gedoen deur karboniel- en waterstofligande tot die sisteem te voeg, gelei deur die 18-elektron reel. Vir hierdie berekeninge is koördinasie deur die terminale suurstowwe gebruik. In beide reeks is dissosiasie-energieë bereken. Die dissosiasie energieë van die M(CO)nHm(0₃) komplekse was deurgaan positief wat aandui dat die komplekse teoreties stabiel is. Die verkrygde golffunksies is hierna analiseer deur middel van drie tegnieke: Atoms in Molecules (AIM), Charge Decomposition Analysis (CDA) en Natural Bond Orbital Analysis (NBO). AIM het getoon dat bindings inderdaad gevorm word tussen die osoonligand en die metal en bet die moontlikheid laat ontstaan dat die bindingsmodel volgens die Dewar-Chatt-Duncason (DCD) model van σ-donasie en л-terugdonasie geïnterpreteer kan word. Hierdie waarneming is bevestig deur CDA. NBO resultate kon nie suksesvol gebruik word nie as gevolg van die hoë graad van electron delokalisasie van die komplekse.
Kinzer, Raymond Edward. "Fourier transform infrared spectroscopy study of small transition-metal carbide clusters". [Fort Worth, Tex.] : Texas Christian University, 2009. http://etd.tcu.edu/etdfiles/available/etd-10152009-103514/unrestricted/kinzer.pdf.
Pełny tekst źródłaTanaka, Yukio, Yasuhiro Asano i Alexander A. Golubov. "Shape of Cooper pairs in a normal-metal/superconductor junction". American Physical Society, 2008. http://hdl.handle.net/2237/11296.
Pełny tekst źródłaWang, Siwen. "Orbital Level Understanding of Adsorbate-Surface Interactions in Metal Nanocatalysis". Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/98923.
Pełny tekst źródłaDoctor of Philosophy
The interactions between reaction intermediates and catalysts should be neither too strong nor too weak for catalytic optimization. This Sabatiers principle arising from the scaling relations among the energetics of reacting species at geometrically similar sites, provides the conceptual basis for designing improved catalysts, but imposes volcano-type limitations on the attainable catalytic activity and selectivity. One of the greatest challenges faced by the catalysis community today is how to develop design strategies and ultimately predictive models of catalytic systems that could circumvent energy scaling relations. This work brings the quantum-chemical modeling and machine learning technique together and develops a novel stochastic modeling approach to rationally design the catalysts with desired properties and bridges our knowledge gap between the empirical kinetics and atomistic mechanisms of catalytic reactions.
Lin, Xi 1973. "First-principles density functional theory study of sulfur oxide chemistry on transition metal surfaces". Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29642.
Pełny tekst źródłaVita.
Includes bibliographical references (p. 297-309).
In this thesis, the chemistry of sulfur oxides on transition metals is studied extensively via first-principles density functional theory (DFT) computations, focusing on the chemical reactivity and selectivity in sulfur poisoning chemical processes that address environmental concerns. The systematic approach we establish can be extended to general computational studies of small gas-phase molecules interacting with extended surfaces or finite-size clusters. The thesis starts with a theoretical presentation of modem quantum many-body theory that brings together mean-field theory, DFT, and Green's function quantum Monte Carlo theory. The essence of chemical reactivity theory in the framework of DFT is emphasized. The thesis continues with an extensive survey of the current status of sulfur oxide chemistry and an overall presentation of our computational approaches towards a detailed understanding of chemical reactivity and selectivity. The basic guidelines in chemical reactivity are systematically constructed by computed comprehensive thermodynamic data of surface S, O, SO, SO2, SO3, and S04 species as a function of coverage at low and intermediate temperatures. Under these basic guidelines, experimentally measured surface spectra are interpreted, contradictory experimental observations are resolved, and applicable experimental measurements are suggested for confirming computational predictions. Moreover, the chemical reactivity study is supplemented by our chemical kinetics study focusing on the catalytic oxidation of SO2 under oxygen rich conditions. This is the key process that hampers the implementation of the next-generation automotive catalytic converter. The revealed Langmuir-Hinshelwood mechanism demonstrates the essential catalytic performance of the Pt(1 11) surface.
(cont.) The thesis closes with a chemical selectivity analysis of the effects of catalyst particle size on chemisorption of gas-phase adatoms. In summary, the presentation of the chemistry of sulfur-containing molecules in this work is aimed at a scientific understanding of the strong poisoning effects in heterogeneous catalysis. However, the chemistry of sulfur-containing molecules has many more fundamental implications, such as in designing novel re-conjugated conducting devices for quantum computers. The underlying hybrid bonding flexibility of sulfur allows it to simultaneously bind to heavy transition metal atoms (such as Pt, Cu, or Au) and first-row atoms (such as oxygen atoms or carbon atoms in organic molecules).
by Xi Lin.
Ph.D.
Martin, Claudia. "Density functional study of the electronic and magnetic properties of selected transition metal complexes". Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2014. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-134958.
Pełny tekst źródłaMelo, Leonardo de. "Powder jet particle density distribution analysis and qualification for the laser metal deposition process". reponame:Repositório Institucional da UFSC, 2015. https://repositorio.ufsc.br/xmlui/handle/123456789/171441.
Pełny tekst źródłaMade available in DSpace on 2016-12-13T03:03:04Z (GMT). No. of bitstreams: 1 340514.pdf: 4063742 bytes, checksum: 6a2f911982008b177bc31b52c459c372 (MD5) Previous issue date: 2015
Abstract: The quality of the Laser Metal Deposition process depends on several factors and components. One of them and also one of the most important is the powder jet. Regular monitoring of the different variables involved on the powder jet need to be performed in order to assure the demanded high stability and quality standards of the produced coating layers. This monitoring is done through process monitoring techniques, where the powder jet is illuminated from the side, by a laser line, and recorded by a coaxially aligned camera through the powder feed nozzle. Symmetry, geometry and position of different levels of the powder jet can be analyzed through relevant algorithms. They also provide calculations of the particle density distribution the recorded images. The spatial particle density distribution of the powder jet can be calculated by superimposing individual levels along the jet. The measurement and monitoring principle was successfully tested with various nozzles and powder properties, making it possible to fully characterize a powder jet.
A qualidade do processo de deposição de metais a laser depende de diversos fatores e componentes. Um dos componentes mais importantes é o fluxo de pó metálico. É necessário o monitoramento contínuo das diferentes variáveis e parâmetros que influenciam no fluxo de pó para se garantir os altos padrões de qualidade e estabilidade requeridos nas peças produzidas. Este monitoramento é realizado através de técnicas de controle de processos, onde o fluxo de pó metálico é iluminado lateralmente, por um laser de iluminação em formato de linha, e gravado por uma câmera coaxial ao bocal alimentador de pó. Simetria, geometria e posição de diferentes níveis do fluxo de pó podem ser analisados através de algoritmos relevantes. Tais algoritmos tornam possíveis também cálculos da distribuição das partículas no fluxo, através da sobreposição de imagens de todos os frames gravados no vídeo em cada nível do fluxo de pó. O processo de medição e análise foi testado com sucesso em diferentes bocais alimentadores de pó e com diferentes materiais e parâmetros do fluxo, tornando possível sua caracterização e qualificação.
Liu, Haitao. "Novel 3-D CMOS and BiCMOS devices for high-density and high-speed ICs /". View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202003%20LIU.
Pełny tekst źródłaWeerawardene, K. L. Dimuthu M. "Optical and luminescence properties of noble metal nanoparticles". Diss., Kansas State University, 2017. http://hdl.handle.net/2097/38189.
Pełny tekst źródłaDepartment of Chemistry
Christine M. Aikens
The remarkable optical and luminescence properties of noble metal nanoparticles (with diameters < 2 nm) attract researchers due to potential applications in biomedicine, photocatalysis, and optoelectronics. Extensive experimental investigations on luminescence properties of thiolate-protected gold and silver nanoclusters during the past decade have failed to unravel their exact photoluminescence mechanism. Herein, density functional and time-dependent density functional theory (DFT and TDDFT) calculations are performed to elucidate electronic-level details of several such systems upon photoexcitation. Multiple excited states are found to be involved in photoemission from Au₂₅(SR)₁₈– nanoclusters, and their energies agree well with experimental emission energies. The Au₁₃ core-based excitations arising due to electrons excited from superatom P orbitals into the lowest two superatom D orbitals are responsible for all of these states. The large Stokes shift is attributed to significant geometrical and electronic structure changes in the excited state. The origin of photoluminescence of Ag₂₅(SR)₁₈– nanoclusters is analogous to their gold counterparts and heteroatom doping of each cluster with silver and gold correspondingly does not affect their luminescence mechanism. Other systems have been examined in this work to determine how widespread these observations are. We observe a very small Stokes shift for Au₃₈(SH)₂₄ that correlates with a relatively rigid structure with small bond length changes in its Au₂₃ core and a large Stokes shift for Au₂₂(SH)₁₈ with a large degree of structural flexibility in its Au₇ core. This suggests a relationship between the Stokes shift of gold−thiolate nanoparticles and their structural flexibility upon photoexcitation. The effect of ligands on the geometric structure and optical properties of the Au₂₀(SR)₁₆ nanocluster is explored. Comparison of the relative stability and optical absorption spectra suggests that this system prefers the [Au₇(Au₈SR₈)(Au₃SR₄)(AuSR₂)₂] structure regardless of whether aliphatic or aromatic ligands are employed. The real-time (RT) TDDFT method is rapidly gaining prominence as an alternative approach to capture optical properties of molecular systems. A systematic benchmark study is performed to demonstrate the consistency of linear-response (LR) and RT-TDDFT methods for calculating the optical absorption spectra of a variety of bare gold and silver nanoparticles with different sizes and shapes.
Huang, Chender 1960. "Characterization of interface trap density in power MOSFETs using noise measurements". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276872.
Pełny tekst źródłaVaddadi, Sridhar. "Computational Studies of Coordinatively Unsaturated Transition Metal Complexes". Thesis, University of North Texas, 2006. https://digital.library.unt.edu/ark:/67531/metadc5488/.
Pełny tekst źródłaCranswick, Matthew A. "Gas-phase Photoelectron Spectroscopy and Computational Studies of Metal-thiolate Interactions: Implications to Biological Electron Transfer". Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195569.
Pełny tekst źródłaLi, Qiang. "Density functional theory studies of biomass conversion on metal surfaces: from small to large molecules". Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/461081.
Pełny tekst źródłaEn esta tesis se han propuesto y calculado una serie de mecanismos de reacción relacionados con diversas moléculas derivadas de biomasa sobre modelos de superficie usando el paquete VASP (Vienna Ab initio simulation package). Se ha realizado una investigación multiescala sobre formación de hidrógeno a partir de moléculas pequeñas de metanol, etanol, etilenglicol y glicerol. Los cálculos de los alcoholes C1 y C2 se realizaron en superficies de Cu(111) y Ru(0001), mientras que los de glicerol sólo en Ru(0001). Se optimizaron las geometrías de enlace de los intermedios completos, así como se ha propuesto la descomposición detallada y los mecanismos de hidrogenación relacionados con dichas especies. Se han analizado las relaciones BEP y TSS y se ha realizado también una simulación microcinética ab initio en diferentes condiciones. Hidrogenación de ácido levulínico a gamma-valerolactona sobre Ru(0001) y sobre Ru(0001) decorada con HHDMA. Se ha propuesto el mecanismo de formación del anillo intramolecular en la superficie de Ru(0001). Se ha elucidado la acidez interfacial y las estructuras locales en la interfaz HHDMA-Ru(0001) que promueven la velocidad de catálisis y la estabilidad frente a la oxidación. Hidrogenación de glucosa y manosa a sus alcoholes de azúcar sobre la superficie de Ru(0001). Las reacciones de los isómeros lineales y cíclicos se han calculado y comparado entre dos moléculas de azúcar y con los resultados experimentales. El autor encontró que concentraciones de diferentes isómeros reactivos en la fase líquida, diferentes energías de adsorción y mecanismos de reacción trabajan juntos para controlar las velocidades de reacción totales. Descomposición de lignina e hidrogenación sobre superficies de Ni(111) y Ni(111) dopadas con Ru. Se han esclarecido los mecanismos de descomposición de la lignina basados en un modelo de dímero más complicado. Los efectos del estereocentro en sus conversiones se han discutido y los efectos de dopaje de Ru promocionando el comportamiento de los catalizadores también se ha aclarado.
In this thesis, a series of surface reaction mechanisms related with various biomass derived molecules on slab models have been proposed and computed by using the Vienna Ab initio simulation package (VASP). 1 Multiscale investigation of hydrogen releasing from small molecules of methanol, ethanol, ethylene glycol, and glycerol have been studied. C1 and C2 alcohols’ calculations are performed both on Cu(111) and Ru(0001) surfaces and glycerol is on Ru(0001). Complete intermediates binding geometries were optimized, detailed decomposition, hydrogenation mechanisms related with these species have been proposed. BEP and TSS relationship have been analyzed and ab initio microkinetic simulation under different conditions has been also performed. 2 Glucose and mannose hydrogenation to their sugar alcohols on Ru(0001) surface. Reactions from linear and ring isomers have been calculated and compared between two sugar molecules, and compared with experiment results. The author found that concentrations of different reactant isomers in the liquid phase, different adsorption energies and reaction mechanisms work together to control the overall reaction rates. 3 Levulinic acid hydrogenation to gamma-valerolactone on Ru(0001) and HHDMA decorated Ru(0001) surface. Intramolecular ring formation mechanism on Ru(0001) surface has been outlined. Interfacial acidity and local structures in the HHDMA-Ru(0001) interface which promote the catalysis rate and stability against oxidation have been illuminated. 4 Lignin decomposition and hydrogenation on Ni(111) and Ru doped Ni(111) surfaces. Lignin decomposition mechanisms based on more complicated dimer model have been clarified. Stereocenter effects in its conversions have been discussed and the Ru doping effects on promoting the catalysts behavior is also elucidated.
Sheen, Paul David. "Towards a hybrid density functional theory and molecular mechanics model for large transition metal systems". Thesis, University of Bath, 1995. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296297.
Pełny tekst źródłaKulkarni, B. S. "Structure and reactivity study of beta zeolite and al metal clusters using density functional theory". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2010. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3753.
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