Bibliografie tematiche / Characterization of plasmas

Letteratura scientifica selezionata sul tema "Characterization of plasmas"

Autore: Grafiati
Pubblicato: 8 giugno 2024

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili

Scegli il tipo di fonte:

Consulta la lista di attuali articoli, libri, tesi, atti di convegni e altre fonti scientifiche attinenti al tema "Characterization of plasmas".

Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.

Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.

Indice

  1. Articoli di riviste
  2. Tesi
  3. Libri
  4. Capitoli di libri
  5. Atti di convegni
  6. Rapporti di organizzazioni

Articoli di riviste sul tema "Characterization of plasmas":

1

Riccardi, C., R. Barni, F. De Colle e M. Fontanesi. "Characterization of electronegative plasmas". Czechoslovak Journal of Physics 50, S3 (marzo 2000): 441–44. http://dx.doi.org/10.1007/bf03165925.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Shufflebotham, P. K., e D. J. Thomson. "Stability and spatial characterization of electron cyclotron resonance processing plasmas". Canadian Journal of Physics 69, n. 3-4 (1 marzo 1991): 195–201. http://dx.doi.org/10.1139/p91-032.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
This paper presents preliminary measurements of the spatial variation of the plasma density, electron temperature, plasma potential, and floating voltage within a divergent magnetic field electron cyclotron resonance (ECR) plasma processing reactor. The measurements are performed using an orbital-motion-limited cylindrical Langmuir probe designed specifically for use in these plasmas. A brief discussion of the stability and uniformity of divergent field plasmas in general, and qualitative techniques for the diagnosis of these properties, is also given. It was found that these plasmas generally occurred in distinct "modes," characterized by unique shapes and dependences on system variables, and between which discontinuous, noisy, and often bistable transitions occurred. Axially resolved probe measurements performed under ECR conditions showed that the plasma density exhibited a broadly peaked profile, while the electron temperature showed a sharp peak at ECR. The differences in these profiles leads to three qualitatively different plasma regions available for use in ECR processing. The variation of the plasma potential explains the origin of the axial ion beams that commonly occur in these systems.
3

Cao, L. F., I. Uschmann, F. Zamponi, T. Kämpfer, A. Fuhrmann, E. Förster, A. Höll et al. "Space-time characterization of laser plasma interactions in the warm dense matter regime". Laser and Particle Beams 25, n. 2 (giugno 2007): 239–44. http://dx.doi.org/10.1017/s0263034607000067.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
Laser plasma interaction experiments have been performed using an fs Titanium Sapphire laser. Plasmas have been generated from planar PMMA targets using single laser pulses with 3.3 mJ pulse energy, 50 fs pulse duration at 800 nm wavelength. The electron density distributions of the plasmas in different delay times have been characterized by means of Nomarski Interferometry. Experimental data were compared with hydrodynamic simulation. First results to characterize the plasma density and temperature as a function of space and time are obtained. This work aims to generate plasmas in the warm dense matter (WDM) regime at near solid-density in an ultra-fast laser target interaction process. Plasmas under these conditions can serve as targets to develop X-ray Thomson scattering as a plasma diagnostic tool, e.g., using the Vacuum ultraviolet (VUV) free-electron laser (FLASH) at Dentsches Elektronen-Synchrotron (DESY) Hamburg.
4

Otorbaev, D. K. ""Simple" diagnostics for characterization of low-pressure chemically active plasmas". Pure and Applied Chemistry 74, n. 3 (1 gennaio 2002): 453–57. http://dx.doi.org/10.1351/pac200274030453.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
In the current paper, the "simple" diagnostics for characterization of nonequilibrium chemically active plasmas are discussed. As to experimental methods, "simple" noninvasive spectroscopic methods of ionizing and recombining plasma characterization have been emphasized. The word "simple" in the title is presented in quotes, which means that the methods are assumed to be simple only conditionally. In order to be sure that the measurements indeed provide correct information on the plasma parameters, a detailed understanding of kinetics of each particular plasma source is required. Moreover, the validity of spectroscopic methods should be checked by independent diagnostic techniques.
5

Amoruso, S., R. Bruzzese, N. Spinelli e R. Velotta. "Characterization of laser-ablation plasmas". Journal of Physics B: Atomic, Molecular and Optical Physics 32, n. 14 (20 luglio 1999): R131—R172. http://dx.doi.org/10.1088/0953-4075/32/14/201.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Nordheden, Karen J., e Joanne F. Sia. "Characterization of BCl3/N2 plasmas". Journal of Applied Physics 94, n. 4 (15 agosto 2003): 2199–202. http://dx.doi.org/10.1063/1.1591075.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Wu, Chi-Chin, Kelsea K. Miller, Scott D. Walck e Michelle Pantoya. "Material Characterization of Plasma-Treated Aluminum Particles via Different Gases". MRS Advances 4, n. 27 (2019): 1589–95. http://dx.doi.org/10.1557/adv.2019.159.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
ABSTRACTThis work describes exploration of mitigating the parasitic amorphous alumina (Al2O3) shell of aluminum nanoparticles (n-Al) and modifying the surface using different plasmas, leading to n-Al with thinner shell and different coatings including carbons and oxidizing salt called aluminum iodate hexahydrate (AIH), respectively. The approach exploits a prototype atmospheric non-thermal plasma reactor with dielectric barrier discharge (DBD) configuration for nanoparticle surface modifications using n-Al of 80 nm average diameter as an example. Preliminary results indicate that the amorphous Al2O3 shell surrounding the active aluminum core can be mitigated with inert plasmas by as much as 40% using either helium (He) or argon (Ar). The particle surface becomes carbon-rich with carbon monoxide (CO) / He plasmas. By immersing the plasma-treated n-Al in an iodic acid (HIO3) solution, AIH crystals can be formed on the n-Al surface. Transmission electron microscopy (TEM) is used as a major tool to study the details of the modified surface morphologies, diffraction patterns, and chemical composition of the modified n-Al. The results demonstrate effective surface passivation of n-Al via atmospheric plasma techniques.
8

RENNER, O., I. USCHMANN e E. FÖRSTER. "Diagnostic potential of advanced X-ray spectroscopy for investigation of hot dense plasmas". Laser and Particle Beams 22, n. 1 (marzo 2004): 25–28. http://dx.doi.org/10.1017/s026303460422105x.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
Modern experimental methods and instruments for X-ray spectral investigation of hot dense plasma provide complex information on environmental conditions in extreme states of matter. The basic spectroscopic conceptions for K-shell plasma diagnosis are outlined, the main characteristics of toroidally bent crystal spectrometers and vertical-dispersion instruments are briefly reviewed. Selected applications (monitoring and optimization of the emission from the femtosecond-laser-produced plasmas, characterization of colliding laser-exploded foils, spectral line merging, and continuum lowering in constrained-flow plasmas) demonstrate the usefulness of advanced spectroscopic methods for plasma diagnostics and fundamental research.
9

Batha, S. H., R. J. Procassini, B. A. Hammel, T. D. Shepard, R. P. Drake, K. S. Bradley, Kent Estabrook et al. "Characterization of titanium laser‐produced plasmas". Physics of Plasmas 2, n. 10 (ottobre 1995): 3792–803. http://dx.doi.org/10.1063/1.871079.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Manos, D. M. "Characterization of laboratory plasmas with probes". Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films 3, n. 3 (maggio 1985): 1059–66. http://dx.doi.org/10.1116/1.573118.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Più fonti
Ti possono interessare anche gli elenchi estesi di opere sul tema "Characterization of plasmas":
Articoli di riviste Tesi Libri

Tesi sul tema "Characterization of plasmas":

1

Gangoli, Shailesh Pradeep Gutsol Alexander Fridman Alexander A. "Design and preliminary characterization of the magnetically stabilized gliding arc discharge /". Philadelphia, Pa. : Drexel University, 2007. http://hdl.handle.net/1860/1860.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Schabel, Michael Joseph 1973. "Characterization of trapped particles in RF plasmas". Thesis, The University of Arizona, 1997. http://hdl.handle.net/10150/291600.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
Particle contamination in plasma processing is a serious and challenging issue for the semiconductor industry. In this work, Laser Doppler Velocimetry, Laser Light Scattering, and Optical Emission Spectroscopy are used to elucidate the physical behavior of particles trapped in a plasma. Coulomb theory is used to describe the motion of particles. The theory agreed very well with experimental data and was explored to evaluate conditions for which particle agglomeration is likely. Finally, it was observed that particles may fall out of the particle trap during plasma ignition and subsequently contaminate the substrate.
3

BIGANZOLI, ILARIA. "Characterization of atmospheric pressure plasmas for aerodynamic applications". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2014. http://hdl.handle.net/10281/53249.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
The use of plasmas in aerodynamics has become a recent topic of interest. In particular, over the last ten years, plasma actuation has received much attention as a promising active method for airflow control. Flow control consists of manipulating the properties of a generic moving fluid with the aim of achieving a desired change, but flow dynamics in proximity of a solid object is usually considered, being a consistent and significant issue in many engineering applications, such as engine, automobile or airplane design. Plasma control of airflows along surfaces has been the subject of several experimental studies whose aim was to reduce turbulence, to decrease drag, to enhance airfoil lift or to prevent flow detachment. The fast temporal response and the absence of moving parts are the most promising features from which plasma actuators could benefit. Different types of plasma sources are currently studied as good candidates for plasma actuation, but Dielectric Barrier Discharges (DBDs) are usually preferred, being characterized by the presence of an insulating barrier between the electrodes. This allows the generation of a non-thermal plasma at atmospheric pressure and prevents the discharge from collapsing into an arc. Surface Dielectric Barrier Discharges (SDBDs) are particularly suitable for these kinds of applications, since plasma is created by ionizing a thin portion of air nearby the surface of the dielectric barrier and this can effectively influence the local properties of the boundary layer associated to an external flow. This thesis deals with SDBDs in an asymmetric configuration where one electrode is glued into an insulating material and to other one is exposed to air, so that plasma is created in correspondence of just one side of the dielectric barrier. The buried electrode is connected to the ground, whereas a sinusoidal high-voltage is applied to the exposed one. It has been noticed that, when these discharges are operated in quiescent air, an airflow of several metres per second is observed above the dielectric sheet and near the plasma region. This is usually called ionic wind because the main mechanism responsible for its generation is believed to be momentum transfer from the ions drifting in the discharge electric field to the surrounding fluid, by particle-particle collisions. When the electric field imposed by the voltage difference between the electrodes is sufficiently high, plasma is created and electrical charges are transported through the gap and accumulated on the insulating surfaces. This charge accumulation generates an electric field that locally weakens the external one. When the total electric field falls below the threshold necessary for plasma ignition, the discharge extinguishes. If the voltage imposed to the fed electrode is increased, the discharge can be locally initiated again, and that is the reason why a sinusoidal high-voltage supply is adopted instead of a continuous one. Consequently, the presence of the insulating barrier usually leads to a regime where charge is mainly transported in sub-millimetre regions consisting of current filaments with temporal duration limited to a few tens of nanoseconds. These plasma microdischarges are concentrated into two phase intervals of the sinusoidal voltage supply, when the modulus of the applied voltage difference is high enough and is increasing in time. These two phases of plasma activity are often called Backward Stroke (BD) and Forward Stroke (FD), depending if the high-voltage signal is rising from its minimum to its maximum or decreasing from its maximum to its minimum. This thesis is motivated by the fact new studies focusing on plasma properties and dynamics are required in order to get better and better aerodynamic results, to understand which parameters mainly affect the actuator performances and to validate numerical models trying to forecast the aerodynamic effects induced by the discharge. This has brought to a scientific collaboration between the Centre of Excellence PlasmaPrometeo of University of Milano-Bicocca and the Aerodynamics and Wind Tunnel Department of the aerospace company Alenia Aermacchi. During these years I have studied the properties of these discharges by means of electrical and optical diagnostics (mainly Rogowski coils, capacitive probes, a photomultiplier tube and a thermal camera). With some of them a temporal resolution high enough for studying several characteristics of plasma microdischarges has been achieved. This is important because these strokes manifest as series of current and light pulses, lasting tens of nanoseconds and a few nanoseconds respectively. I have first of all carried out a detailed investigation of the properties of these events and of their evolution in space and time in the course of the FD and BD. It has been pointed out that there are several analogies between the BD and FD, but that not all plasma properties are identical for the two semi-cycles, because of the asymmetrical configuration adopted. These investigations let think that light and current signals give insights about different microdischarge properties. Light is presumably ascribable to electrons that excite nitrogen immediately after the passage of the ionizing wave that initiates the microdischarge. In contrast, the current signal is due to the movement of charges into the plasma channel and thus reflects the microdischarge temporal evolution, rather than its formation. In the following experiments I have thus focused mainly on the electrical properties of plasma microdicharges, with the aim of better understanding which plasma characteristics are responsible for the ionic wind generation and properties. Several SDBDs with different geometrical configurations and operating parameters have been considered. It has been found that both the discharge and ionic wind characteristics are mainly affected by the dielectric thickness, whereas other properties of the SDBD are less decisive. These studies are of practical interest because optimizations of SDBD characteristics are still needed for adopting these discharges as plasma actuators for active flow control. In particular, it has been found that at first the speed of the induced wind increases quite linearly with the voltage amplitude, but then this velocity and thus the aerodynamic effects induced by the discharge tend to saturate. This is particularly evident when thin panels are adopted as dielectric barriers. I thus focused on this topic and I found that an asymmetry in the total charge transported by plasma microdischarges during the backward and forward strokes is favourable for obtaining a ionic wind with a greater velocity, and that the velocity saturation at the highest voltages is associated to a change in discharge regime, which is visible first of all because a pattern of plasma filaments appears superimposed to the more homogeneous plasma. I have thus characterized how this regime transition affects the dynamics of the backward and forward strokes. Three groups of microdischarges have been identified, depending on their temporal duration, and results let think that they don't contribute equally to the electric wind generation. These studies pave the way to a better understanding of the discharge peculiarities and ionic wind formation, with the aim of understanding if an intrinsic limit exists in plasma actuator potentialities or if new optimization strategies are possible. Eventually, I proposed to implement the Background Oriented Schlieren (BOS) technique for the visualization and characterization of the airflow induced by the discharge. The potentialities of this technique have been evaluated in relation to the specifics of the available scientific equipment. The technique has then been proved to be able to visualize density changes induced by plasma. A spatial characterization of the air near the discharge was made in stationary wall jet conditions as well as in the transient period following the discharge ignition when a starting vortex is generated.
4

Ellsworth, Jennifer L. "Characterization of low-frequency density fluctuations in dipole-confined laboratory plasmas". Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62691.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 161-167).
Low-frequency fluctuations of plasma density, floating potential, ion saturation current, visible light intensity, and edge magnetic field are routinely observed in the Levitated Dipole Experiment (LDX). For the purposes of this thesis, we define low-frequency as W << Wbe where Wbe is the electron bounce frequency. These fluctuations in a laboratory dipole confined plasma lead to turbulence mixing that maintain peaked density profiles. The relationship between the different types of low-frequency fluctuations and plasma density transport is considered. Two 16-channel photodiode arrays were designed and constructed to study the spatial and temporal structure of these fluctuations as part of this dissertation. In addition to the photodiode arrays, a four-channel microwave interferometer is used to estimate the density profile and to measure density fluctuations in the plasma. Several electrostatic probes, including a 24-channel floating probe array, measure fluctuations at the plasma edge and eight Mirnov coils measure magnetic fluctuations. The fluctuations fall into three general categories: broadband, turbulent fluctuations observed during nearly all plasma conditions; quasi-coherent fluctuations with low azimuthal mode numbers and peak frequencies on the order 1 kHz observed during discharges with low neutral pressure; and coherent fluctuations with zero toroidal mode number and peak frequencies on the order of 100 Hz, observed during discharges with moderate neutral fueling. The relationship between time-averaged fluctuation characteristics and plasma parameters are explored. The spatial structure of the fluctuations for several representative shots are discussed. The turbulent fluctuations and concurrent density profiles are compared to quasilinear diffusion of interchange mixing in dipolar plasmas for cases where the fluctuations are random. I show that the quasilinear diffusion equation agrees well with the experimental observations of random fluctuations, supporting the conclusion that interchange mixing is causing inward transport that results in peaked density profiles. For other cases, where nonlinear effects appear to dominate the plasma dynamics, the saturated fluctuation amplitudes are compared to the plasma density profiles.
by Jennifer L. Ellsworth.
Ph.D.
5

Fassina, Alessandro. "Thermal and transport characterization of rfp plasmas from electron temperature data". Doctoral thesis, Università degli studi di Padova, 2010. http://hdl.handle.net/11577/3427058.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
The work deals with electron tempearature and transport analysis in RFP plasams; in particular the following topics are discussed: - the commissioning of the edge Thomson Scattering in RFX-mod for temperature evaluation; - the commissioning of the laser blow-off system in RFX-mod for impurity transport characterization -the analysis of RFP helical states in term of electron temperature, diffusivity and confinement on the experiments RFX-mod (Padua) and MST (madison, WI).
Il presente lavoro sviluppa una caratterizzazione dei plasmi RFP dal punto di vista termico e di trasporto; in particolare vengonodiscussi i seguenti punti: -lo sviluppo della diagnostica di Thomson Scattering di bordo per la misura della temperaturea elettronica; -lo sviluppo del sistema di laser blow off per l'iniezione di impurezze e lo studio del loro trasporto -l'analisi degli stati elicoidali negli RFP, in termini di caratteristiche termiche e di confinamento, negli esperimenti RFX-mod(Padova) e MST(Madison-WI)
6

Ferioli, Francesco. "Experimental characterization of laser-induced plasmas and application to gas composition measurements". College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2953.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
Thesis (Ph. D.) -- University of Maryland, College Park, 2005.
Thesis research directed by: Mechanical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
7

Mavadat, Maryam. "Characterization of biomedical used plasmas by IR and UV-VIS emission spectroscopy". Thesis, Université Laval, 2014. http://www.theses.ulaval.ca/2014/30780/30780.pdf.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
La modification de surface par plasma est une technique largement utilisée pour améliorer les propriétés de surface de polymères par le greffage de différents groupes fonctionnels. Dans ce projet de recherche, différentes méthodes pour améliorer les techniques de caractérisation de décharge micro-ondes de N2 et N2-H2 ont été étudiées dans le but d’optimiser le procédé de traitement de surface par plasma. Tout d'abord, un certain nombre de paramètres du plasma ont été mesurés à différentes conditions de traitement. Pour déterminer les paramètres du plasma, la spectroscopie d'émission optique a été utilisée dans la région l’ultraviolet, du visible et l’infrarouge (rarement utilisée dans la littérature scientifique). L’utilisation de la spectroscopie d'émission dans cette dernière région spectrale est avantageuse car elle permet d'éliminer les forts chevauchements entre les transitions atomiques et moléculaires et de pallier la faible intensité du signal observée dans la région de l’ultraviolet et du visible. Par la suite, la composition chimique de surface du PTFE a été analysée par XPS pour déterminer les concentrations en carbone, fluor, azote et des groupements amine suite à un traitement par plasma. Les résultats mentionnés ci-dessus ont été utilisés pour corréler les conditions de traitement et les paramètres de décharge micro-ondes à la composition chimique du PTFE modifié, dans l’objectif de mettre en évidence les paramètres expérimentaux du plasma et les espèces présentes dans le plasma qui jouent un rôle clé pour maximiser la fonctionnalisation de surface du polymère avec des groupements amine. En outre, un modèle mathématique a été développé en utilisant la technique de régression PLS. Pour construire ce modèle, un ensemble de données de variables d'entrée contenant les conditions de traitement et les paramètres spectroscopiques du plasma et une matrice de réponse contenant les propriétés de surface du polymère ont été générées. La base de données obtenue a été utilisée pour établir la relation entre les paramètres du plasma, les conditions de traitement et la chimie de surface du film. Cela a finalement permis de prédire la composition chimique de la surface à partir d’informations relatives au plasma, sans avoir à effectuer des analyses de surface après le traitement.
Plasma surface modification is a widely used technique for improving the surface properties ‎of ‎polymers through the introduction of different functional groups. In ‎the current research project, ‎different methods to improve the characterization techniques of ‎N2 and N2-H2 microwave discharge ‎were investigated with the aim of optimizing the ‎plasma surface process. First of all, a number of plasma parameters were measured at ‎different process conditions. To determine the plasma ‎parameters, optical emission spectroscopy was used ‎not only within the well-documented ‎UV-Visible region but also within the rarely ‎studied infrared zone. Using infrared optical emission ‎spectroscopy is advantageous as it ‎eliminates the strong overlap between atomic and molecular ‎transitions as well as the low ‎intensity UV-Visible emission spectroscopy limitations. In the next step, the PTFE surface chemical composition was analyzed via XPS to quantify the ‎concentrations of carbon, fluorine, and nitrogen after a plasma treatment in a N2-H2 gaseous ‎environment. The XPS analyses were also performed after chemical derivatization to quantify the ‎surface concentration of amino groups (%NH2) at different process conditions. The above-mentioned results were used to correlate process conditions and microwave N2-‎H2 ‎discharge‏ ‏parameters‏ ‏to the chemical composition of the modified ‎PTFE. The purpose was ‎to ‎determine the external plasma parameters and species present within the plasma ‎which ‎‎play a key ‎role in the introduction of amino groups to the polymer surface. ‎Furthermore, a mathematical model was developed using ‎the Partial Least Squares ‎Regression, ‎‎(PLSR) ‎using custom scripts written in MATLAB. A data set of ‎input variables including the process conditions ‎and plasma ‎parameters for each experiment ‎were generated along with the corresponding response ‎matrix which in turn contained the ‎surface ‎properties of the film.‎ ‎The resulting database was used to ‎build the relationship ‎between the plasma parameters, ‎process condition and the resulting film ‎surface chemistry. ‎This ultimately enabled to predict the PTFE surface chemistry from data originating ‎from the plasma, without having to proceed to post-plasma surface characterization.
8

Hofmans, Marlous. "Experimental characterization of helium plasma jets". Thesis, Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAX062.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
Cette thèse porte sur l’étude d’un jet de plasma d'hélium à pression atmosphérique alimenté par des impulsions positives unipolaires à une fréquence de l’ordre du kHz. Des expériences sont effectuées pour caractériser la dynamique de propagation, la structure de l'écoulement et la température dans un jet en expansion libre, ainsi que l'influence d'une cible métallique sur le plasma.La spectroscopie à polarisation Stark indique un champ électrique axial d'environ 10 kV/cm dans le capillaire du jet et une augmentation jusqu'à 20 kV/cm dans le panache, qui est constante pour différentes amplitudes et durées de l'impulsion de tension appliquée. La diffusion Thomson et la diffusion Raman rotationnelle sont utilisées pour déterminer la densité électronique et la température électronique, à différentes positions axiales et radiales, ainsi que la température du gaz et la densité de N2 et O2 de l'air environnant qui sont mélangés dans le flux d’hélium.La comparaison quantitative de ces résultats expérimentaux avec les résultats d'un modèle fluide 2D montre une bonne concordance et permet une meilleure compréhension des résultats obtenus, à savoir que le champ électrique dans le front d'ionisation augmente avec la quantité d’air intégré au flux d’hélium au lond de la propagation. L'imagerie Schlieren révèle l'apparition de structures turbulentes à des débits élevés et lors de l'application des impulsions de tension. On constate que la température du gaz, mesurée par une sonde de température, augmente d'environ 12 C quand le plasma est allumé et d'environ 25 C lorsqu'une cible métallique est placée devant le jet
This thesis studies an atmospheric pressure helium plasma jet that is powered by positive, unipolar pulses at a kHz frequency. Experiments are performed that focus on the propagation dynamics, flow structure and temperature in a freely expanding jet, as well as the influence of a metallic target on the plasma.Stark polarization spectroscopy yields an axial electric field of around 10 kV/cm in the capillary of the jet and an increase up to 20 kV/cm in the plume, which is constant for different amplitudes and durations of the applied voltage pulse. Thomson and rotational Raman scattering are used to determine the electron density and electron temperature, at different axial and radial positions, as well as the gas temperature and the density of N2 and O2 that are mixed into the helium from the surrounding air.Quantitative comparison of these experimental results with results from a 2D fluid model show a good agreement and allow for a better understanding of the obtained results, namely that the electric field in the ionization front depends linearly on the flow composition at that location. Schlieren imaging shows the onset of turbulent structures at high applied flow rates and at the application of the voltage pulses. The gas temperature, as measured by a temperature probe, is found to increase by around 12 C when the plasma is ignited and by around 25 C when a metallic target is placed in front of the jet
9

Fanara, C. "A Langmuir multi-probe system for the characterization of atmospheric pressure arc plasmas". Thesis, Cranfield University, 2003. http://dspace.lib.cranfield.ac.uk/handle/1826/96.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
The 'high-pressure' atmospheric (TIG) arc plasma is studied by means of a multi-Langmuir probe system. In order to determine the appropriate regime of operation, definitions of the plasma parameters for the description of the argon arc are considered and evaluations are presented. A description of the probe basic techniques is followed by an in-depth discussion of the different regimes of probe operation. The emphasis is put on atmospheric and flowing (arc) regimes. Probe sheath theories are compared and “Nonidealities” like cooling due to plasma-probe motion and probe emission mechanisms are then described. The extensive literature review reveals that the existing probe theories are inappropriate for a use in the TIG arc, because of ‘high’ pressure (atmospheric), broad range of ionization across the arc, flowing conditions, and ultimately, to the uncertainty about onset of Local Thermodynamical Equilibrium. The Langmuir probe system is built to operate in floating and biased conditions. The present work represents the first extensive investigation of electrostatic probes in arcs where the experimental difficulties and the primary observed quantities are presented in great detail. Analysis methodologies are introduced and experimental results are presented towards a unified picture of the resulting arc structure by comparison with data from emission spectroscopy. Results from different measurements are presented and comparison is made with data on TIG arcs present in literature. Probe obtained temperatures are lower than the values obtained from emission spectroscopy and this ‘cooling’ is attributed to electron-ion recombination. However, it is believed that probes can access temperatures regions not attainable by emission spectroscopy. Only axial electric potential and electric field are obtained because of the equipotential-probe requirement. Estimations of the sheath voltage and extension are obtained and a qualitative picture of the ion and electron current densities within the arc is given.
10

Murad, Saad Kheder. "Characterization of dry etching processes of III-V semiconductors in silicon tetrachloride plasmas". Thesis, University of Glasgow, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297037.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Più fonti

Libri sul tema "Characterization of plasmas":

1

Patterson, Michael J. Ground-based plasma contactor characterization. [Cleveland, Ohio: National Aeronautics and Space Administration, Lewis Research Center, 1987.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Patterson, Michael J. Ground-based plasma contactor characterization. [Cleveland, Ohio: National Aeronautics and Space Administration, Lewis Research Center, 1987.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Patterson, Michael J. Ground-based plasma contactor characterization. [Cleveland, Ohio: National Aeronautics and Space Administration, Lewis Research Center, 1987.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Albers, John J., e Jere P. Segrest. Plasma lipoproteins: Characterization, cell biology, and metabolism. Orlando: Academic Press, 1986.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
5

United States. National Aeronautics and Space Administration., a cura di. Characterization of hollow cathode, ring cusp discharge chambers. Fort Collins, Colo: Dept. of Mechanical Engineering, Colorado State University, 1989.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Mandeep. Characterization and plasma protein binding studies of surface modified polyethersulfone. Ottawa: National Library of Canada, 2001.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

A, Heelis Rodney, e United States. National Aeronautics and Space Administration., a cura di. Adaptive identification and characterization of polar ionization patches. [Washington, D.C: National Aeronautics and Space Administration, 1997.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Filiaggi, Mark J. Interface characterization of the plasma sprayed ceramic coating/metal implant system. Ottawa: National Library of Canada, 1990.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Lambert, G. L. Isolation, characterization and cloning of plasmids from hydrogen producing cyanobacteria. Luxembourg: Commission of the European Communities, 1985.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Caughill, Denise. Isolation and characterization of a plasmid from Pseudomonas fluorescens PF 13525. Sudbury, Ont: Laurentian University, 1998.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Più fonti

Capitoli di libri sul tema "Characterization of plasmas":

1

Kono, Mitsuo, e Miloš M. Škorić. "Multifractal Characterization of Plasma Edge Turbulence". In Nonlinear Physics of Plasmas, 481–507. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-14694-7_14.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Sahiner, M. Alper. "Characterization of Local Structures in Plasma Deposited Semiconductors by X-ray Absorption Spectroscopy". In Complex Plasmas, 299–320. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-05437-7_9.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Hidalgo, C., B. Gonçalves e M. A. Pedrosa. "Characterization of Turbulence in Terms of Probability Density Function". In Nonequilibrium Phenomena in Plasmas, 257–72. Dordrecht: Springer Netherlands, 2005. http://dx.doi.org/10.1007/1-4020-3109-2_12.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Geindre, J. P., P. Audebert, F. Falliès, A. Rousse, J. C. Gauthier, A. Antonetti, J. P. Chambaret, G. Grillon e A. Mysyrowicz. "Phase-Sensitive Characterization of Short-Scale-Length Plasmas". In Springer Series in Chemical Physics, 269–70. Berlin, Heidelberg: Springer Berlin Heidelberg, 1994. http://dx.doi.org/10.1007/978-3-642-85176-6_96.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Robert, S., E. Francke e J. Amouroux. "Hydrodynamic and Electrical Characterization of a Corona Discharge Plasma Reactor". In Advanced Technologies Based on Wave and Beam Generated Plasmas, 483–84. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-017-0633-9_27.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Ganeev, Rashid A. "Harmonic Characterization Using Different HHG Schemes in the Extended Plasmas". In Frequency Conversion of Ultrashort Pulses in Extended Laser-Produced Plasmas, 189–208. Singapore: Springer Singapore, 2016. http://dx.doi.org/10.1007/978-981-10-0194-9_7.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Zhang, C. H., S. Katsuki, J. G. Shi, H. Horita, T. Namihira e H. Akiyama. "Characterization of Solid Tin Target for Gas Discharges Produced EUV Plasmas". In Solid State Phenomena, 885–88. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/3-908451-30-2.885.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Rockstroh, T. J., e J. Mazumder. "Characterization of Laser-Induced Plasmas and Temperature Measurement During Laser Surface Treatment". In Laser Surface Treatment of Metals, 23–29. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4468-8_4.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Geohegan, David B. "Spectroscopic and ion probe characterization of laser produced plasmas used for thin film growth". In Laser Ablation Mechanisms and Applications, 28–37. New York, NY: Springer New York, 1991. http://dx.doi.org/10.1007/bfb0048350.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Charbonnier, M., M. Romand, M. Alami e Tran Minh Duc. "Surface modification of poly(tetrafluoroethylene) in RF glow-discharge (H2, He, Ar, O2, N2, NH3) plasmas. XPS characterization". In Polymer Surface Modification: Relevance to Adhesion, Volume 2, 3–27. London: CRC Press, 2023. http://dx.doi.org/10.1201/9780429070419-2.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri

Atti di convegni sul tema "Characterization of plasmas":

1

Kolner, Brian H., Philip M. Conklin, Nicolas K. Fontaine, Robert A. Buckles e Ryan P. Scott. "Terahertz Characterization of Pulsed Plasmas". In Optical Terahertz Science and Technology. Washington, D.C.: OSA, 2005. http://dx.doi.org/10.1364/otst.2005.md4.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Miller, Paul A. "Electrical characterization of rf plasmas". In Process Module Metrology, Control and Clustering, a cura di Cecil J. Davis, Irving P. Herman e Terry R. Turner. SPIE, 1992. http://dx.doi.org/10.1117/12.56631.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Steffens, Kristen L. "2-D Temperature Mapping in Fluorocarbon Plasmas". In CHARACTERIZATION AND METROLOGY FOR ULSI TECHNOLOGY 2005. AIP, 2005. http://dx.doi.org/10.1063/1.2062985.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Geindre, J.-P., P. Audebert, F. Falliès, A. Rousse, J. C. Gauthier, A. Antonetti, J. P. Chambaret, G. Grillon e A. Mysyrowicz. "Phase sensitive characterization of short scale-length plasmas." In International Conference on Ultrafast Phenomena. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/up.1994.wc.14.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
By irradiation of solid targets with intense femtosecond pulses it is possible to create microplasmas of very small gradient scale length l/λ<0.1. Useful information on the early evolution of these plasmas on a picosecond or even subpicosecond time scale can be obtained via optical detection. For instance, subpicosecond time-resolved Schlieren measurements can determine the location of the critical density layer of the plasma.[1] However diffraction effects limit the accuracy to a value of the order of the incident wavelength. A method to detect plasma velocities relies on the spectral analysis of the reflected probe beam at different delays.[2] Expansion velocities can be inferred from Doppler shifts. However, the large Fourier spectrum Δω≈1/Δt of short pulses makes it difficult to estimate frequency shifts much less than Δω. Furthermore, this method is sensitive to the detrimental shot-to-shot frequency and spatial fluctuations of the lasers.
5

Landen, O. L., E. M. Campbell e M. D. Perry. "X-ray characterization of picosecond laser plasmas". In AIP Conference Proceedings Volume 160. AIP, 1987. http://dx.doi.org/10.1063/1.36716.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Steffens, Kristen L., e Mark A. Sobolewski. "Spatial uniformity in chamber-cleaning plasmas measured using planar laser-induced fluorescence". In CHARACTERIZATION AND METROLOGY FOR ULSI TECHNOLOGY. ASCE, 1998. http://dx.doi.org/10.1063/1.56831.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

richards, caleb, Igor Adamovich, David Mignogna, Dirk van den Bekerom e Elijah Jans. "CHARACTERIZATION OF HYBRID NS PULSE/RF PLASMAS AND ATMOSPHERIC PRESSURE PLASMA JETS". In 2021 International Symposium on Molecular Spectroscopy. Urbana, Illinois: University of Illinois at Urbana-Champaign, 2021. http://dx.doi.org/10.15278/isms.2021.wc08.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Scales, Wayne, Chen Chen, José Tito Mendonça, David P. Resendes e Padma K. Shukla. "Characterization of Dusty Plasmas in the Earth’s Mesosphere Using Radiowave Heating". In MULTIFACETS OF DUSTRY PLASMAS: Fifth International Conference on the Physics of Dusty Plasmas. AIP, 2008. http://dx.doi.org/10.1063/1.2997280.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Blesener, K. S., I. C. Blesener, D. A. Hammer, R. Doron, Y. Maron, E. Kroupp, V. Bernshtam, L. Weingarten e Y. Zarnitsky. "Visible spectroscopy characterization of aluminum X pinch plasmas". In 2012 IEEE 39th International Conference on Plasma Sciences (ICOPS). IEEE, 2012. http://dx.doi.org/10.1109/plasma.2012.6383922.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Sarjeant, W. J., A. Halstead, K. Burke, R. Lange, J. Mahan e H. Moore. "Characterization of Exploding Film Plasmas Using Emission Spectroscopy". In Conference Record of the 2006 Twenty-Seventh International Power Modulator Symposium. IEEE, 2006. http://dx.doi.org/10.1109/modsym.2006.365306.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri

Rapporti di organizzazioni sul tema "Characterization of plasmas":

1

HEBNER, GREGORY A., ION C. ABRAHAM e JOSEPH R. WOODWORTH. Characterization of SF6/Argon Plasmas for Microelectronics Applications. Office of Scientific and Technical Information (OSTI), marzo 2002. http://dx.doi.org/10.2172/793326.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Kuo, Spencer P. Generation Characterization and Aerospace Applications of Torch Plasmas. Fort Belvoir, VA: Defense Technical Information Center, maggio 2004. http://dx.doi.org/10.21236/ada426130.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Villa-Aleman, E. Characterization Of High Explosives Detonations Via Laser-Induced Plasmas. Office of Scientific and Technical Information (OSTI), ottobre 2015. http://dx.doi.org/10.2172/1223195.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
4

McQuaid, Michael J., e Michael J. Nusca. Thermodynamic Property Characterization for Plasmas Generated by an Ablating-Capillary Arc. Fort Belvoir, VA: Defense Technical Information Center, marzo 2001. http://dx.doi.org/10.21236/ada393297.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Sankaran, R. Mohan. Collaborative Research: Understanding Nanoparticle-Plasma Interactions in Dusty Non-Thermal Plasmas by Nanoparticle Probes and Online Aerosol Characterization. Office of Scientific and Technical Information (OSTI), febbraio 2023. http://dx.doi.org/10.2172/1924640.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Hogan, Christopher. Collaborative Research: Understanding Nanoparticle-Plasma Interactions in Dusty Non-Thermal Plasmas by Nanoparticle Probes and Online Aerosol Characterization: Final Technical Report. Office of Scientific and Technical Information (OSTI), ottobre 2020. http://dx.doi.org/10.2172/1712951.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Kolasinski, Robert, Chun-Shang Wong, Josh A. Whaley e Frances Allen. In-situ spectroscopic ellipsometry for real-time characterization of the effects of high-flux helium plasmas on tungsten surfaces. Office of Scientific and Technical Information (OSTI), febbraio 2020. http://dx.doi.org/10.2172/1599984.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Cortés Ortigosa, Francisco, e María Pascual Mora. Characterization of the extraction method of extracellular vesicles by HDL and LDL contamination. Fundación Avanza, maggio 2023. http://dx.doi.org/10.60096/fundacionavanza/2902022.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
In this study we assess and validate the method of extraction of extracellular vesicles found in blood plasma with commercial kits to exclude potential contamination by plasma HDL and LDL particles using immunoblot analysis.
9

Crain, Marlon D., Yitzhak Maron, Bryan Velten Oliver, Robert L. Starbird, Mark D. Johnston, Kelly Denise Hahn, Thomas Alan Mehlhorn e Darryl W. Droemer. Volumetric plasma source development and characterization. Office of Scientific and Technical Information (OSTI), settembre 2008. http://dx.doi.org/10.2172/942062.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

VerMeulen, Holly, Jay Clausen, Ashley Mossell, Michael Morgan, Komi Messan e Samuel Beal. Application of laser induced breakdown spectroscopy (LIBS) for environmental, chemical, and biological sensing. Engineer Research and Development Center (U.S.), giugno 2021. http://dx.doi.org/10.21079/11681/40986.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Abstract (sommario):
The Army is interested in sensors capable of characterizing/monitoring the environment (battlefield or military training ranges) at proximal distances. Recently, we evaluated laser induced breakdown spectroscopy (LIBS) systems (hand-held, proximal, and bench top) for the characterization of metals (antimony, copper, lead, tungsten, and zinc) in soils obtained from military training ranges. We then compared the results to findings obtained with standard field and laboratory instrumentation for metals analysis -X-ray Fluorescence (XRF) and Inductively Couple Plasma- Optical Emission Spectroscopy (ICP-OES).

Vai alla bibliografia