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Plasma ionization

Figure 2 Relationship of SIMS, separate bombardment SNMSs and direct bombardment SNMSd. (a) Materials for SIMS analysis are those ions formed In the sputtering with a focused primary ion beam. The largest fraction of the particles sputtered from the surface are neutral atoms, (b) Ions for SNMS analysis are formed by ionization of the sputtered neutrals, (c) When the plasma is used as an ionizer, plasma ions can also be used to sputter the sample surface at low energies. Figure 2 Relationship of SIMS, separate bombardment SNMSs and direct bombardment SNMSd. (a) Materials for SIMS analysis are those ions formed In the sputtering with a focused primary ion beam. The largest fraction of the particles sputtered from the surface are neutral atoms, (b) Ions for SNMS analysis are formed by ionization of the sputtered neutrals, (c) When the plasma is used as an ionizer, plasma ions can also be used to sputter the sample surface at low energies.
Sample introduction into the ionizing plasma is normally carried out in the same manner as for ICP-OES. An aqueous soludon is nebulized and swept into the plasma. [Pg.627]

Positive secondary ions (SI" ) are repelled by an electrode in e-beam SNMS or completely (in DBM) or widely (in HFM, see below) re-attracted by the sample surface in HF-plasma SNMS. Ionized plasma species (Ar", contamination) are suppressed by energy filtering. [Pg.125]

After post-ionization in the 3 cm long cylindrical plasma space between sample surface and the opposite wall, SN" enter a 90° electrostatic ion energy analyzer (ion optics) suppressing ionized plasma gas particles to a degree of 10 -10 noise levels are correspondingly low (1 cps). The transmission of the electrostatic ion optics is in the range of a few per cent. [Pg.126]

In fact, an apparent doping effect was also reported by Schwan et al. [39] in a-C(N) H films deposited by the highly ionized plasma beam deposition technique in C2H2-N2 atmospheres. Schwan et al. also observed thermally activated behavior for the conductivity. As reported by Silva et al. [14], they also observed increasing optical gap, and decreasing ESR spin signal, but the Urbach energy was found to increase. [Pg.271]

Lx>ng radiative lifetimes of metastable states support the high density of these particles in slightly ionized plasma, or in excited gas. Thus, according to Fugal and Pakhomov [18, 19] the density of metastable atoms of helium at pressure of the order of a few Torrs, at temperatures ranging from 4 to 300 K, is about two orders of magnitude above the density of electrons. The density of metastable atoms and molecules in... [Pg.281]

Hypocalcemia associated with hypoalbuminemia requires no treatment because ionized plasma calcium concentrations are normal. [Pg.901]

In partly ionized plasmas, where both the charged and neutral particles are in concentrations large enough to make measurable contributions to the refractive index, single wavelength interferometry cannot separate that part of refractivity resulting from the neutral components. [Pg.53]

The application of holography to plasma interferometry has several advantages 276) accurate alignment and precision optical elements are not required. A complete three-dimensional record of the interference phenomena is obtained and the technique is well suited to record stationary and transient plasmas. Two-wavelength holographic interferometry of partially ionized plasmas has been performed by Jeffries 277). [Pg.53]

There recently had been much discussion of fire and the role it must have played in forming the mental world of archaic human beings. Once, as we sat staring into the camp fire, Dennis had remarked to me that, "People have been looking into fires like this for thousands and thousands of years. The squeal of these coals is the release of ionized plasma and in the flickering waves of free electrons thus created, one can see into the past and the future. The fire is the place where the ideas come from."... [Pg.80]

Cook (Ref 2) detected the production of a highly ionized plasma region. It was found to originate more directly from the explosive than from thermal ionization associated with the accompanying shock wave, and to be of the same nature as current flow in a metal... [Pg.420]

Calcium is present in three forms e.g., as free calcium ion, bound to plasma protein albumin and in diffusable complexes. The endocrine system, through parathyroid hormone and calcitonin, helps in keeping the concentration of ionized plasma calcium in normal level. Decrease in plasma levels of ionized calcium leads to increased parathyroid hormone secretion. Parathyroid hormone tends to increase plasma calcium level by increasing bone resorption, increasing intestinal absorption and increasing reabsorption of calcium in kidney. Vitamin D acts by stimulating... [Pg.390]

Ion source Atomization Ionization Plasma temperature Electron density Ions measured Vacuum condition Mass analyzer utilized Application... [Pg.72]

Glow discharge ion source in Ar plasma Penning and e ionization plasma 3000-6000 ne 1015 cm-3 M+ low pressure double-focusing SFMS (reverse Nier-Johnson) traces, high-purity metals... [Pg.72]

KINETIC THEORY FOR CHEMICALLY REACTING GASES AND PARTIALLY IONIZED PLASMAS... [Pg.175]

V. Kinetic Theory of Fluctuations in Partially Ionized Plasmas References... [Pg.176]

In the second part we will consider the formulation of kinetic equations for partially ionized plasmas including ionization and recombination of the atoms. [Pg.177]

In principle, such approximations may serve as a basis of the description of partially ionized plasmas, if we have to take into account ionization and recombination. However, because of the long range of Coulomb interaction, the Landau collision integral (3.110) and such integrals of type (3.119) are divergent. Such divergencies may be avoided by an appropriate screening. The simplest way to do this is to replace the... [Pg.227]

In a partially ionized gas there are two limiting situations, the state with zero degree of ionization, that is, a neutral gas, and the state of a fully ionized plasma. As a starting point we take the first state in which all particles are bound. We wish to find a suitable description of such a system of interacting composite particles (atoms) starting with the basic properties of the interacting elementary particles (e, p). [Pg.229]

In (4.44), there occurs the product Up, which must be determined. We will do this in the so-called polarization approximation, which takes into account the polarization of the medium. This approximation is known from the theory of the fully ionized plasma and was discussed in detail in Refs. 12 and 28. A least approximately, the same method may be applied to an atomic gas with internal degrees of freedom. [Pg.237]

Until now we considered the limiting situation in which the plasma consists only of atoms. The kinetic equation was given by Eq. (4.62). However, we are also interested in describing the partially ionized plasma, and especially the ionization and recombination reactions. Formally, this corresponds to taking into account scattering states in Eq. (4.44). This means that the quantum numbers a may be discrete numbers and. may also run over the continuous spectrum. Taking into account scattering states, we are faced with difficulties. These are connected essentially with the application of Eq. (4.28) in the equation of motion. [Pg.241]

In this section we want to deal with the kinetic theory of fluctuations in partially ionized plasmas. [Pg.247]

The theory of fluctuations in partially ionized plasmas may be developed in full analogy to the fluctuation theory of gases or fully ionized plasmas. The latter is developed in detail in Refs, 5, 12, and 28. [Pg.247]


See other pages where Plasma ionization is mentioned: [Pg.2796]    [Pg.230]    [Pg.107]    [Pg.14]    [Pg.125]    [Pg.390]    [Pg.394]    [Pg.225]    [Pg.482]    [Pg.411]    [Pg.415]    [Pg.111]    [Pg.112]    [Pg.143]    [Pg.26]    [Pg.136]    [Pg.56]    [Pg.12]    [Pg.96]    [Pg.49]    [Pg.505]    [Pg.107]    [Pg.842]    [Pg.230]    [Pg.505]    [Pg.199]    [Pg.419]   
See also in sourсe #XX -- [ Pg.18 ]

See also in sourсe #XX -- [ Pg.50 ]




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Inductively coupled plasma ionization

Ionization in plasmas

Ionized plasmas

Ionized plasmas

Laser Plasma Ionization

Plasma Ionization Mass Spectrometry

Plasma completely ionized

Plasma desorption ionization

Plasma fully ionized

Plasma ionization energy

Plasma ionization multicollector mass spectrometry

Plasma partially ionized

Saha Equation for Ionization Equilibrium in Thermal Plasma

Weakly ionized plasma

Weakly ionized plasma electron kinetics

Weakly ionized plasma electrons

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