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Momentum analyser

Since the trajectory is independent of the mass, the electric field is not a mass analyser, but rather a kinetic energy analyser, just as the magnetic field is a momentum analyser. Note that the electric sector separates the ions according to their kinetic energy. [Pg.145]

Florida State University tandem accelerator. The accelerated ions were focused onto a 10 pg/cm carbon foil, Foil-1 in fig. 2, placed near the entrance slits of a 90° momentum analysing magnet. Fully stripped ions were selected by the magnet and then passed through a second, nominally 5 pg/cm foil, Foil-2. Here approximately 30% of the ions captured an electron to produce of which... [Pg.690]

If these assumptions are satisfied then the ideas developed earlier about the mean free path can be used to provide qualitative but useful estimates of the transport properties of a dilute gas. While many varied and complicated processes can take place in fluid systems, such as turbulent flow, pattern fonnation, and so on, the principles on which these flows are analysed are remarkably simple. The description of both simple and complicated flows m fluids is based on five hydrodynamic equations, die Navier-Stokes equations. These equations, in trim, are based upon the mechanical laws of conservation of particles, momentum and energy in a fluid, together with a set of phenomenological equations, such as Fourier s law of themial conduction and Newton s law of fluid friction. When these phenomenological laws are used in combination with the conservation equations, one obtains the Navier-Stokes equations. Our goal here is to derive the phenomenological laws from elementary mean free path considerations, and to obtain estimates of the associated transport coefficients. Flere we will consider themial conduction and viscous flow as examples. [Pg.671]

In this ehapter, the transport proeesses relating to partiele eonservation and flow are eonsidered. It starts with a brief introduetion to fluid-particle hydrodynamics that deseribes the motion of erystals suspended in liquors (Chapter 3) and also enables solid-liquid separation equipment to be sized (Chapter 4). This is followed by the momentum and population balances respeetively, whieh deseribe the eomplex flows and mixing within erystallizers and, together with partieulate erystal formation proeesses (Chapters 5 and 6), enable partiele size distributions from erystallizers to be analysed and predieted (Chapters 7 and 8). [Pg.26]

Conservation is a general concept widely used in chemical engineering systems analysis. Normally it relates to accounting for flows of heat, mass or momentum (mainly fluid flow) through control volumes within vessels and pipes. This leads to the formation of conservation equations, which, when coupled with the appropriate rate process (for heat, mass or momentum flux respectively), enables equipment (such as heat exchangers, absorbers and pipes etc.) to be sized and its performance in operation predicted. In analysing crystallization and other particulate systems, however, a further conservation equation is... [Pg.45]

However, as mentioned above, T c)3) will be orthogonal to all the k states, and T ) is nonzero. This implies that the number of total states of the same eigenvalue E is (k + 1), which contradicts our initial hypothesis. Thus, we conclude that k must be even, and hence proved the generalized Kramers theorem for total angular momentum. The implication is that we can use double groups as a powerful means to study the molecular systems including the rotational spectra of molecules. In analyses of the symmetry of the rotational wave function for molecules, the three-dimensional (3D) rotation group SO(3) will be used. [Pg.674]

In this section, we shall look at the way these various absorptions are analysed by spectroscopists. There are four kinds of quantized energy translational, rotational, vibrational and electronic, so we anticipate four corresponding kinds of spectroscopy. When a photon is absorbed or generated, we must conserve the total angular momentum in the overall process. So we must start by looking at some of the rules that allow for intense UV-visible bands (caused by electronic motion), then look at infrared spectroscopy (which follows vibrational motion) and finally microwave spectroscopy (which looks at rotation). [Pg.459]

The preceding analyses hold only for circular fuel jets. Roper [10] has shown, and the experimental evidence verifies [11], that the flame height for a slot burner is not the same for momentum- and buoyancy-controlled jets. Consider a slot burner of the Wolfhard-Parker type in which the slot width is x and the length is L. As discussed earlier for a buoyancy-controlled situation, the diffusive distance would not be x, but some smaller width, say xb. Following the terminology of Eq. (6.25), for a momentum-controlled slot burner,... [Pg.328]

Analyses of flows involving deflagration and detonation fronts in gas have been made by Rankine (Ref 2), Hugoniot (Ref 2), Dixon (Ref 4), Chapman (Ref 5) and Jouguet (Refs 6 7). These analyses based on the laws of conservation of mass, momentum and energy predicted detonation velocities in good agreement with the experimental results obtd from detonation in flame tubes... [Pg.604]

Here, the thermo-fluid analyses are performed using the computational fluid dynamics code STAR-CD (Computational Dynamics Ltd.) [9], In STAR-CD, the algebraic finite-volume equations are solved. The solid and fluid parts are divided into small discrete meshes, and in each mesh, the following differential equations governing the conservation of mass, momentum, and energy are solved. [Pg.331]


See other pages where Momentum analyser is mentioned: [Pg.690]    [Pg.144]    [Pg.690]    [Pg.144]    [Pg.673]    [Pg.566]    [Pg.18]    [Pg.79]    [Pg.273]    [Pg.40]    [Pg.227]    [Pg.221]    [Pg.290]    [Pg.175]    [Pg.1190]    [Pg.212]    [Pg.474]    [Pg.306]    [Pg.149]    [Pg.448]    [Pg.363]    [Pg.428]    [Pg.115]    [Pg.319]    [Pg.793]    [Pg.12]    [Pg.86]    [Pg.205]    [Pg.181]    [Pg.324]    [Pg.227]    [Pg.289]    [Pg.359]    [Pg.168]    [Pg.88]    [Pg.146]    [Pg.25]    [Pg.409]    [Pg.428]    [Pg.284]    [Pg.36]    [Pg.32]   
See also in sourсe #XX -- [ Pg.144 ]




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