Дисертації з теми "Emissive cathode"
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Asselin, Daniel Joseph. "Characterization of the Near-Plume Region of a Low-Current Hollow Cathode." Digital WPI, 2011. https://digitalcommons.wpi.edu/etd-theses/438.
Повний текст джерелаSary, Gaétan. "Modélisation d'une cathode creuse pour propulseur à plasma." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30182/document.
Повний текст джерелаA hollow cathode is a critical component of plasma thrusters. In a plasma thruster, a propellant gas is ionized in a discharge chamber and accelerated out of it so as to generate thrust. In Hall thrusters in particular, the ionization of the gas is caused by an intense electron current (from a few to hundred amps) which flows through the discharge chamber. The hollow cathode is the device which is responsible for providing the discharge current. This key element is often idealized in thruster numerical models and its physical behavior is rarely studied for its own sake. Yet, developing high power Hall thrusters, designed to propel in the long run every type of space mission, requires new hollow cathodes able to supply an intense electron current (over 100 A) over a duration on the order of ten thousand hours. So far, designing new cathodes proved difficult because of the lack of model capable of predicting the performance of a cathode based on its design. In this work, we build up a predictive model of a hollow cathode capable of simulating the physics relevant to the operation of the cathode. In the end, we aim at using this model to associate design characteristics of the cathode to key aspects of the cathode performance during operation. Our goal with this model is to guide the development of future high power hollow cathodes. We will first briefly describe the range of application of hollow cathodes related to space propulsion. Then we will give a brief account of the working principles of the cathode and we will set the numerical models available in the literature prior to this one out. The numerical model developed in this work will then be described. It includes a fluid treatment of the plasma as well as an account of the heat fluxes to the walls which largely control the performance of the cathode. Simulation results will be thoroughly compared to experimental measurements available in the literature and specific aspects of the model will be refined to match up simulation results with the physical reality. For instance, a model that specifically represents the transition region between the internal plasma of the cathode and the plume of the cathode will be described. This model will enable us to highlight plasma instability phenomena which were so far observed experimentally, yet never properly included in hollow cathode models. Using the model just developed, we will analyze the physics of a particular hollow cathode which has been developed by NASA at the Jet Propulsion Laboratory, the NSTAR hollow cathode. Then, thanks to the numerical model, we will be able to carry out a parametric study revolving around the design of the NSTAR cathode. This will allow us to bring out the influence of the design on the cathode performance and we will eventually express recommendations regarding the design of future high power cathodes. To conclude, the versatility of the numerical model built up here will also be displayed through simulations of the behavior of a hollow cathode based on an alternate geometry
Pagaud, Francis. "Control and stability of magnetised plasma columns : plasma-cathode interactions and helicon plasma operation." Electronic Thesis or Diss., Lyon, École normale supérieure, 2024. http://www.theses.fr/2024ENSL0016.
Повний текст джерелаRadial transport, azimuthal waves and instabilities are common features in magnetised plasmas, causing major challenges for plasma propulsion, plasma wakefield particle acceleration or fusion devices. Plasma properties control is desirable yet complex. This PhD thesis follows two goals, one being the use of an emissive cathode as a new parameter control and the other being the fundamental understanding of the helicon plasma operational stability. Firstly, the role of the injection of electrons inside a magnetised plasma column has been studied experimentally and numerically. The experimental set-up is a 80 cm long and 20 cm diameter vacuum vessel connected to a 11 cm wide glass tube. The argon gas at a base pressure of 0.13 Pa is ionised by a 3-turns inductive radio-frequency antenna supplied at 1 kW. Magnetic field ranging from 170 G to 340 G, ensures a weak magnetisation of the plasma. A large tungsten hot cathode was placed at the end of the plasma column to inject an important thermionic current. Electrical and optical measurements of the cathode temperature revealed a highly inhomogeneous cathode temperature profile due to plasma–cathode interactions. A detailed thermal modelling solved numerically accurately reproduces the heterogeneous rise in temperature witnessed experimentally. The operating regime was predicted in excellent agreement with experimental results.The fine understanding of the emissive cathode behaviour in presence of a surrounding magnetised plasma permitted to explore its influence on the plasma properties, and especially the plasma potential. An analytical approach based on a two-fluids plasma model and anisotropic electrical conductivities, predicting plasma potential control and plasma rotation regulation as a function of thermionic emission, has been applied and compared to a wide experimental dataset of plasma properties. The works presented confront the role of cross-field ion transport to experimental radial plasma potential scans with a semi-quantitative agreement, highlighting a new major application of emissive cathodes.Finally, a state-of-the-art helicon plasma source has been implemented to produce higher ionization rates. This new system required a complete characterisation of plasma properties through electrostatic probes and high-speed camera imaging. It reproduced well-known helicon plasma features such as E-H-W mode transitions, bistability and hysteresis, chirality emerging from the external magnetic field direction and the propagation of m = +1 whistler waves. Besides, it displayed complex behaviours such as H-W and W-W oscillations, or coexisting low-frequency Kelvin-Helmholtz and Rayleigh-Taylor instabilities. A strong multiscale core instability at 1080 G was also briefly investigated. Wave-mode identification based on theoretical growth rates, 2DFT modal decomposition and POD has been conducted, unravelling the physical mechanisms at stake
Taillefer, Zachary R. "Characterization of the Near Plume Region of Hexaboride and Barium Oxide Hollow Cathodes operating on Xenon and Iodine." Digital WPI, 2018. https://digitalcommons.wpi.edu/etd-dissertations/44.
Повний текст джерелаPopov, M. Yu, A. P. Volkov, S. G. Buga, V. S. Bormashov, K. V. Kondrashov, R. L. Lomakin, N. V. Lyparev, V. V. Medvedev, S. A. Tarelkin, and S. A. Perfilov. "Nanostructured metal-fullerene field emission cathode." Thesis, Sumy State University, 2011. http://essuir.sumdu.edu.ua/handle/123456789/20585.
Повний текст джерелаVaughn, Joel M. "Thermionic Electron Emission Microscopy Studies of Barium and Scandium Oxides on Tungsten." Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1279814656.
Повний текст джерелаLee, Kon Jiun. "Current limiting of field emitter array cathodes." Diss., Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/19629.
Повний текст джерелаShen, Xiangqian. "Novel processing routes for oxide cathode emission materials." Thesis, Loughborough University, 2000. https://dspace.lboro.ac.uk/2134/10822.
Повний текст джерелаMollart, T. P. "Electron emission processes in cold cathode thermal arcs." Thesis, Durham University, 1993. http://etheses.dur.ac.uk/5546/.
Повний текст джерелаJones, Randolph D. "Circuit model of a low-voltage field emission cathode." Diss., Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/15631.
Повний текст джерелаLysenkov, Dmitry. "Optimization of nanostructures for field emission cathodes." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=979952913.
Повний текст джерелаSanborn, Graham Patrick. "A thin film triode type carbon nanotube field electron emission cathode." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50302.
Повний текст джерелаSchlise, Charles A. "Explosive emission cathodes for high power microwave devices /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Jun%5FSchlise.pdf.
Повний текст джерелаCooper, Joseph Andrew. "Investigation of the effects of process variables on the properties of europium-doped yttrium oxide phosphor." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/20503.
Повний текст джерелаKandah, Munther Issa. "Particles emission control at graphite cathode in arc ion plating deposition." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ55420.pdf.
Повний текст джерелаKandah, Munther. "Particles emission control at graphite cathode in arc ion plating deposition." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35434.
Повний текст джерелаBajic, Stevan. "Non-metallic cold-cathode electron emission from composite metal-insulator microstructures." Thesis, Aston University, 1989. http://publications.aston.ac.uk/8063/.
Повний текст джерелаHirt, Benjamin David. "Impact of Additives on Thermionic Cathodes." Ohio University Honors Tutorial College / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors1524832507214002.
Повний текст джерелаSwartzentruber, Phillip D. "MICROSTRUCTURE AND WORK FUNCTION OF DISPENSER CATHODE COATINGS: EFFECTS ON THERMIONIC EMISSION." UKnowledge, 2014. http://uknowledge.uky.edu/cme_etds/41.
Повний текст джерелаWu, Qiong. "Measurements and studies of secondary electron emission of diamond amplified photo cathode." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3337275.
Повний текст джерелаTitle from PDF t.p. (viewed on Jul 29, 2009). Source: Dissertation Abstracts International, Volume: 69-12, Section: B, page: 7588. Adviser: Shyh-Yuan Lee.
Pozdnyakov, D. V., A. V. Borzdov, and V. M. Borzdov. "Calculation of Current-Voltage Characteristics of the Optimized Triode with a Cold Cathode Based on the Ordered Array of Single-Wall Metallic Carbon Nanotubes." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35361.
Повний текст джерелаAyzatskiy, N., A. Dovbnya, V. Zakutin, N. Reshetnyak, V. Romas'ko, I. Chertishchev, V. N. Boriskin, V. Mitrochenko, A. B. Galat, and I. Khodak. "Experimental investigation on the time characteristics of an electron beam formed in the magnetron gun with a secondari-emission cathode." Thesis, Национальный научный центр "Харьковский физико-технический институт" (ННЦ ХФТИ), 2007. http://openarchive.nure.ua/handle/document/9244.
Повний текст джерелаPatel, Jay. "GROWTH AND CHARACTERIZATION OF CARBON NANOMATERIALS." Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1310148312.
Повний текст джерелаMagnus, Sandra Hall. "An Investigation of the relationship between the thermochemistry and emission behavior of thermionic cathodes based on the BaO-Sc₂O₃-WO₃ ternary system." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/19625.
Повний текст джерелаSabaut, Lucie. "Cathode commutable à nanotubes de carbone pour tube à rayons X." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLX078/document.
Повний текст джерелаThis work chooses to improve the electron source by replacing thermionic emission with field emission. More especially, carbon nanotubes based cold cathodes stand out by their ability to supply high currents (>1A/cm^2) while responding fast.Through the development of an innovative structure of in-plane gated carbon nanotube based cathode, this study aims at making switchable and regulated sources for miniature, portable or polyvalent X-rays sources.The electrostatic modelling of the new structure led to the fabrication of optimized gated cathodes, where a vertically aligned array of carbon nanotubes is grown. Default analysis allows to get reliable insulated devices.Field emission characterization shows unprecedented current modulation of 10^6 at +/-40V bias voltage. Current regulation is also achieved with a stability of 0.02% over 100 h.Another structure with a burried gate electrode was designed to successfully cope with leak current and parasitic growth. A new way of growing short and thin nanotubes was tackled.Finally, gated cathodes were integrated in a compact X-ray tube and showed a current modulation of 2000 at a high voltage of 60 kV
Yang, Sen. "Characterization of low voltage cathodo-luminescent phosphors for field emission displays." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/30859.
Повний текст джерелаO'Neill, Kevin. "Field Emission from Excimer Laser Processed a-Si:H Thin Film Cathodes." Thesis, University of Dundee, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.521675.
Повний текст джерелаPottinger, Sabrina. "Investigation of steady state characteristics of hollow cathode internal plasmas using optical emission spectroscopy." Thesis, University of Southampton, 2005. https://eprints.soton.ac.uk/345074/.
Повний текст джерелаKnápek, Alexandr. "Metody přípravy a charakterizace experimentálních autoemisních katod." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-233613.
Повний текст джерелаMunné, Vicente. "Investigation of barium titanate PTCR films for current limiting of field emitter arrays." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/19612.
Повний текст джерелаNeuerman, Robert A. "Simulation and design methods for free-electron laser systems." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Dec/09Dec%5FNeuerman.pdf.
Повний текст джерелаThesis Advisor(s): Colson, William B. ; Blau, Joseph. "December 2009." Description based on title screen as viewed on January 28, 2010. Author(s) subject terms: Free-electron lasers, FEL simulations, undulators, FEL oscillators, FEL amplifiers, diamond field-emitter arrays, field emission cathodes, cathode test cell. Includes bibliographical references (p. 45). Also available in print.
Forrest, Roy Duncan. "Electron field emission from amorphous semiconductor thin films." Thesis, University of Surrey, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.484237.
Повний текст джерелаLittle, Scott A. "Experimental and numerical studies of a new thermionic emitter structure based on oxide coated carbon nanotubes operating at large emission currents." Virtual Press, 2007. http://liblink.bsu.edu/uhtbin/catkey/1380104.
Повний текст джерелаDepartment of Physics and Astronomy
Liu, Xiaotao. "CHARACTERIZATION OF NANOSTRUCTURE, MATERIALS, AND ELECTRON EMISSION PERFORMANCE OF NEXT-GENERATION THERMIONIC SCANDATE CATHODES." UKnowledge, 2019. https://uknowledge.uky.edu/cme_etds/96.
Повний текст джерелаDel, Pozo Rodriguez Sofia. "Investigation and optimisation of a plasma cathode electron beam gun for material processing applications." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/13565.
Повний текст джерелаSerbun, Pavel [Verfasser]. "A systematic investigation of carbon, metallic and semiconductor nanostructures for field-emission cathode applications / Pavel Serbun." Wuppertal : Universitätsbibliothek Wuppertal, 2014. http://d-nb.info/1048757064/34.
Повний текст джерелаMroz, Michael V. "Characterization of Morphological and Chemical Properties of Scandium Containing Cathode Materials." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou158470102410177.
Повний текст джерелаCalderón-Colón, Xiomara Zhou Otto. "Fabrication, characterization and integration of carbon nanotube cathodes for field emission x-ray source." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2009. http://dc.lib.unc.edu/u?/etd,2721.
Повний текст джерелаTitle from electronic title page (viewed Mar. 10, 2010). "... in partial fulfillment of the requirement for the degree of Doctor of Philosophy in the Curriculum in Applied Science and Engineering." Discipline: Applied and Materials Sciences; Department/School: Applied and Materials Sciences.
Chalamala, Babu Reddy. "The Physics of Gaseous Exposures on Active Field Emission Microcathode Arrays." Thesis, University of North Texas, 1996. https://digital.library.unt.edu/ark:/67531/metadc278588/.
Повний текст джерелаNavitski, Aliaksandr [Verfasser]. "Scanning field emission investigations of structured CNT and MNW cathodes, niobium surfaces and photocathodes / Aliaksandr Navitski." Wuppertal : Universitätsbibliothek Wuppertal, 2010. http://d-nb.info/1009494678/34.
Повний текст джерелаDong, Chen Dan. "Scaling of ultrafast photon-triggered field emission cathodes composed of arrays of sharpened single-crystal Si pillars." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/100329.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (pages 53-55).
Ultrafast (<1 ps-long pulses) cathodes with spatially structured emission are an enabling technology for exciting applications such as free-electron lasers, tabletop coherent x-ray sources, and ultrafast imaging. In this thesis, we explore the scaling down and multiplexing limits of ultrafast photon-triggered field emission cathodes composed of arrays of nano-sharp high-aspect-ratio silicon pillars. We are interested in exploring how the geometry of the array and the morphology of the pillars affect the emission of the electrons. Both the multi-photon regime and the strong-field tunneling regime of the emission process were studied using near-IR pulses at various pulse energies. We model the structure using 2D and 3D COMSOL Multiphysics, collect the charge-energy characteristics of the actual devices, compare and interpret the results from both simulations and experiments. We find that the field factor is a strictly increasing function of the pitch at the fixed height, and the field factor saturates when the pitch is very large. The field factor is also strictly increasing with respect to the height with a diminishing return. In addition, due to the trade-off between the field factor and the pitch scaling, there exists an optimum pitch at 2.5 [mu]m, which yields the highest emission of electrons. This work also confirms earlier work by the group on the emission characteristics and polarization dependence: at low pulse energy, the emission is in the multiphoton regime and has an sin² ([theta]) dependence on the polarization; at high pulse energy, the emission is in the strong-field tunneling regime and has an sin²([theta]) dependence on the polarization.
by Chen Dan Dong.
M. Eng.
Christy, Larry A. "Field Emission Properties of Carbon Nanotube Fibers and Sheets for a High Current Electron Source." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1406819279.
Повний текст джерелаCheng, An-jen Tzeng Y. "Cold cathodes for application in poor vacuum and low pressure gas environments carbon nanotubes versus zinc oxide nanoneedles /." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Spring/master's/CHENG_AN-JEN_7.pdf.
Повний текст джерелаHudanski, Ludovic. "Modulation d'un faisceau électronique issu d'une cathode à base de nanotubes de carbone - Applications aux tubes hyperfréquences." Phd thesis, Ecole Polytechnique X, 2008. http://pastel.archives-ouvertes.fr/pastel-00004268.
Повний текст джерелаDionne, Martin. "Optimized carbon nanotube array cathodes for thermo-field emission in plasmas: a theoretical model and an experimental verification." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97045.
Повний текст джерелаDans le cadre de ce projet nous avons développé un modèle en 3-D pour l'émission électronique par effet thermo-champ stimulée par un plasma. Nos premiers résultats ont indiqué que des réseaux denses de nanotubes de carbone (NTC) agissant en tant qu'émetteurs dans le vide pouvaient supporter les températures résultant de densité de courant moyennes très élevées de l'ordre de celles présentes dans les taches cathodiques d'arcs opérant sur des cathodes non-réfractaires. Une étude comparative des modèles pour l'émission électronique pour les surfaces froides soumises à de forts champs électriques a révélé l'existence d'une relation simple entre l'équation imprécise de Fowler-Nordheim (F-N) et le résultat accepté fourni par la théorie de Murphy et Good (M-G). Nous avons donc proposé une équation paramétrique précise et simple pour la densité de courant émise. L'usage de la théorie de M-G a aussi fourni une explication pour l'effet de refroidissement à la pointe décrit dans une étude précédente sur la destruction de NTC émettant par effet de champ: l'effet Nottingham. Pour des émetteurs très courts, cet effet particulier chauffe la surface et accélère le processus de destruction et pour de longs émetteurs, il crée une petite zone isotherme à la pointe de l'émetteur qui est détruite lorsqu'elle atteint une température critique (approximativement 1850 K). Lorsque combiné à des données sur la longueur de l'émetteur, son diamètre, la tension appliquée et le courant mesuré, notre modèle peut fournir le travail de sortie de l'émetteur, sa résistivité à la température ambiante et la valeur de la résistance de contact thermique entre l'émetteur et son substrat. Une autre version de ce modèle inclut un calcul du champ électrique de surface en présence d'un plasma froid. À cette fin, nous avons modifié le modèle développé par Mackeown et obtenu un résultat général pour des surfaces en 3-D. Cette expression générale requiert le calcul du facteur d'amplification du flux ionique, lequel peut être obtenu en résolvant l'équation de Laplace au dessus de la structure d'intérêt. Cette approche simple nous permet de décrire comment les ions sont redistribués à l'intérieur de la gaine vers la pointe des NTC où le champ électrique augmente. Ces prédictions ont été testées en développant simultanément un procédé de fabrication pour une électrode composite correspondant au schéma optimisé que nous suggérions. Des patrons d'oxyde anodique d'aluminium furent utilisés en tant que substrats pour faire croître nos réseaux de NTC mais afin de faciliter leur usage à grande échelle nous avons modifié le procédé de production des NTC pour permettre l'usage directe d'aluminium commercial anodisé. Nos électrodes furent ensuite utilisées comme cathodes dans des décharges à basse pression. Les tensions et densités de courant mesurées sont différentes des valeurs typiques rencontrées dans les décharges électroluminescentes utilisant comme électrodes, des surfaces d'aluminium. En fait, en raison du très faible travail de sortie des sites d'émission pointus et relativement ordonnés et de la présence simultanée d'un patron de céramique autour d'eux, nos électrodes ont produit des points d'attachement très diffus pour le plasma d'une façon similaire à ce qui est observé pour des cathodes réfractaires chaudes telles que le tungstène. Les tensions d'opération, dans la plage 38-140 V, sont de beaucoup inférieures aux tensions observées avec des électrode d'aluminium (>200 V). Nos électrodes ont aussi démontré leur capacité de maintenir ces décharges à basse tension pour au moins 500 heures si leur température moyenne était maintenue sous 60 Celsius et si de la vapeur d'eau était ajoutée au gaz injecté. Nos expériences dans des mélanges d'azote et d'eau ont démontré la faisabilité de produire de larges quantités de photons UV pour un potentiel anodique (cathode mise à la terre) de 90-100 V. Ces résultats sont très prometteurs pour de futures applications en éclairage.
Orozco, Nieto Pedro Francisco. "Manufacturing strategy for high current cold field emission cathodes : floating catalyst chemical vapour deposition grown carbon nanotube fibres and films enhanced by laser patterning and laser purification process." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/278104.
Повний текст джерелаSchmitt, Thorsten. "Resonant Soft X-Ray Emission Spectroscopy of Vanadium Oxides and Related Compounds." Doctoral thesis, Uppsala University, Atomic and molecular physics, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4290.
Повний текст джерелаThis thesis addresses the electronic structure of vanadium and copper oxides using soft X-ray absorption (SXA) spectroscopy and resonant inelastic X-ray scattering (RIXS) at high brightness synchrotron radiation sources. In RIXS incident photons, tuned to the energy of specific absorption resonances, are inelastically scattered leaving behind a low energy valence excitation in the system studied. Effects of electron localization are reflected by the occurrence of low-energy excitations in form of dd- and charge-transfer excitations that are modelled by cluster calculations. Band-like states are dominating when the intermediate core excited state is delocalized.
RIXS at V 2p and O 1s resonances has been used to study the electronic structure of the monovalent vanadium oxides VO2 and V2O3, and of the mixed valence compounds, NaV2O5 and V6O13. For NaV2O5 and V6O13 significant contributions from localized low-energy excitations reflect the partly localized character of their valence band electronic structure, whereas VO2 and V2O3 appear mostly as band-like. Effects of carrier doping are addressed for the case of Mo doping into VO2 and reveal a quasi-rigid band behavior. In the cases of VO2 and V6O13 the temperature dependent metal-insulator transition could be monitored by following the spectral evolution of bands originating from V 3d and V 3d - O2p hybridized states. For Na2V3O7 nanotubes it was possible to selectively probe states from the apical and the basal oxygen sites of VO5 pyramids that constitute these nanotubes. Furthermore, the RIXS technique has been demonstrated to be highly valuable in characterizing the charge transfer processes that accompany lithium insertion into vanadium oxide battery cathodes. Finally, for insulating cuprates RIXS at O 1s, Cu 3p and Cu 3s resonances has been recorded at high-resolution for the detailed investigation of crystal field excitations.
Vašíček, Martin. "Charakterizace autoemisních zdrojů pro elektronovou mikroskopii." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220188.
Повний текст джерелаORLIKOWSKI, JEAN-PIERRE. "Contribution a l'etude des cathodes a emission de champ a effet schottky : utilisation a basse tension, dans un canon a lentille magnetique incorporee." Reims, 1990. http://www.theses.fr/1990REIMS013.
Повний текст джерелаCousin, Richard. "Compréhension des mécanismes régissant le fonctionnement d'un tube hyperfréquence de type MILO (Magnetically Insulated Line Oscillator)." Phd thesis, Ecole Polytechnique X, 2005. http://pastel.archives-ouvertes.fr/pastel-00001651.
Повний текст джерела