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Infinite slit

If, in the detector plane, the effective slit is wider than the region of the pattern in which significant intensity is observed, the approximation of an infinite slit is valid. Let the slit be infinitively long in ft -direction but very narrow in 53-direction then in the tangent plane approximation the recorded scattering curve... [Pg.57]

V Vu w(a,p,y) w(N, r) W t) wq volume of a polymer segment. 6.1.1.3 scattering volume. 1.2.2 unit cell volume. 3.3.1 crystallite orientation distribution function. 3.6.3 end-to-end distribution of a Gaussian chain. 5.2.1 [5.12] slit-length weighting function. 5.6.1 constant value of W(t) with infinite slit approximation. 5.6.3... [Pg.320]

Figure 4.7. Intensity of scattering, corrected for infinite slits, against scattering angle (26) for a solvent-cast film of triblock polymer, styrene-butadiene-styrene, having segment molecular weights of 21,100, 63,400, and 21,100 g/mol. (McIntyre and Campos-Lopez, 1970.)... Figure 4.7. Intensity of scattering, corrected for infinite slits, against scattering angle (26) for a solvent-cast film of triblock polymer, styrene-butadiene-styrene, having segment molecular weights of 21,100, 63,400, and 21,100 g/mol. (McIntyre and Campos-Lopez, 1970.)...
So far in our consideration of small-angle diffraction behaviour we have not considered the effective of diffuse interfacial layers. Porod showed that the tail i.e. the asymptotic behaviour at high angles) of a scattering curve for an ideal two-phase system with sharp boundaries between the phases should have an intensity proportional to s " for a system studied with point collimation and proportional to s when studied with infinite slit collimation. [Pg.164]

A more detailed treatment has been given by Gurfein and his associates who chose as their pore model a cylinder with walls only one molecule thick. A few years later, Everett and Fowl extended the range of models to include not only a slit-shaped pore with walls one molecule thick, but also a cylinder tunnelled from an infinite slab of solid and a slit formed from parallel slabs of solid. [Pg.207]

FIG. 3 Setup of simulation cell of confined electrolyte with periodic boundary conditions, (a) Electrolyte bound by two infinitely long charged plates, representing a slit pore, (b) Electrolyte in a cylindrical nanopore. [Pg.631]

For the case of isotropic scattering recorded with slit-focus cameras there are several desmearing options. If the slit may be considered infinite, the observed scattering intensity is... [Pg.58]

Asymmetrical peaks with a steep decrease towards high scattering angle are typical for data recorded by a slit-focus (Kratky camera). An isotropic and infinitely sharp peak at s0, (J(s) = 8(s — so)), measured by means of an ideal slit becomes... [Pg.116]

In order to achieve the best possible resolution, the thickness of the ray being attenuated should have infinitely small width. However, this is practically impossible since in that case, we need to have an infinitely small slit width of the detector collimator also. If the slit width is too small, the counts registered by the detectors will be very small, which in turn will affect the resolution. Generally, the maximum resolution that can be attained is equivalent to the slit width. In the new setup, a collimator with a slit width of 2 mm is used instead of 5 mm, which was the case in old CT unit. This is expected to result in a higher resolution of the order of 2 mm (Fig. 3c). [Pg.62]

Adsorption in ultramicroporous carbon was treated in terms of a slit-potential model by Everett and Powl51 and was later extended by Horvath and Kawazoe.52 They assumed a slab geometry with the slit walls comprised of two infinite graphitic planes. Adsorption occurs on the two parallel planes, as shown in figure 2.7. [Pg.47]

Sofar the imaging results of Fig. 3.1 were discussed in very classical terms, using the notion of a set of trajectories that take the electron from the atom to the detector. However, this description does not do justice to the fact that atomic photoionization is a quantum mechanical proces. Similar to the interference between light beams that is observed in Young s double slit experiment, we may expect to see the effects of interference if many different quantum paths exist that connect the atom to a particular point on the detector. Indeed this interference was previously observed in photodetachment experiments by Blondel and co-workers, which revealed the interference between two trajectories by means of which a photo-detached electron can be transported between the atom and the detector [33]. The current case of atomic photoionization is more complicated, since classical theory predicts that there are an infinite number of trajectories along which the electron can move from the atom to a particular point on the detector [32,34], Nevertheless, as Fig. 3.2 shows, the interference between trajectories is observable [35] when the resolution of the experiment is improved [36], The number of interference fringes smoothly increases with the photoelectron energy. [Pg.48]

To develop such better approximations we must extend the OZ equation so that it can be applied to fluids in a slit and to colloids. We can do this by regarding the supporting fluid as a component in a mixture of large and small particles. The large particles are the colloidal particles (or, if they are infinitely large, the walls of the slit). Following Henderson et al. [32] (HAB), we start with the OZ equations for a mixture... [Pg.565]

Boundary effects on the electrophoretic mobility of spherical particles have been studied extensively over the past two decades. Keh and Anderson [8] applied a method of reflections to investigate the boundary effects on electrophoresis of a spherical dielectric particle. Considered cases include particle motions normal to a conducting wall, parallel to a dielectric plane, along the centerline in a slit (two parallel nonconducting plates), and along the axis of a long cylindrical pore. The double layer is assumed to be infinitely thin... [Pg.598]

Deep electrophoretic penetration of spherical particles with infinitely thin double layer into an impermeable porous graphite substrate was examined by modeling the porous medium as a long slit with one closed end [44]. [Pg.606]

The reason behind this statement lies in the fact that separately measuring each standard deviation, (AA)2 and (AB)2, makes product, V((AA)2(AB)2) = AAAB this relationship can be experimentally tested. Thus, for the momentum-position operators, the quantum state prepared as a plane wave, that is, an eigenstate of the momentum operator, Ap = 0, so that Ar must be infinite in such a way that the product has a lower bound, namely, ft/2. Hereafter, we select the direction of the momentum along the x-axis to simplify the discussion. Including a screen perpendicular to x-direction, the possibility to define position and momentum of a system passing a slit located at the plane xs is limited by the screen observables uncertainties... [Pg.58]

It is the presence of the uncertainty products that would state us that an interaction took place between the incoming quantum state and the quantum states from the slit (not explicitly incorporated) in Hilbert space leads to a scattered state combining both, one can easily understand the emergence of diffraction effects. It is not the particle model that will indicate us this result. The scattered quantum state suggests all (infinite) possibilities the quantum system has at disposal. One particle will only be associated with one event at best yet, the time structure of a set of these events may be the physically significant element (see Section 4.1). [Pg.59]

To examine the interactions, the origin for the slits is given on the y-axis. The plane wave propagates along the x-axis so that Spy is zero by construction and Sy must be infinite in such a way that an equivalent to inequality Eq. (9) holds (replace z-axis by y-axis only). [Pg.61]


See other pages where Infinite slit is mentioned: [Pg.57]    [Pg.714]    [Pg.62]    [Pg.580]    [Pg.230]    [Pg.41]    [Pg.253]    [Pg.206]    [Pg.206]    [Pg.207]    [Pg.104]    [Pg.109]    [Pg.111]    [Pg.287]    [Pg.57]    [Pg.714]    [Pg.62]    [Pg.580]    [Pg.230]    [Pg.41]    [Pg.253]    [Pg.206]    [Pg.206]    [Pg.207]    [Pg.104]    [Pg.109]    [Pg.111]    [Pg.287]    [Pg.131]    [Pg.27]    [Pg.37]    [Pg.631]    [Pg.58]    [Pg.28]    [Pg.32]    [Pg.62]    [Pg.149]    [Pg.710]    [Pg.157]    [Pg.303]    [Pg.235]    [Pg.75]   
See also in sourсe #XX -- [ Pg.39 ]

See also in sourсe #XX -- [ Pg.39 ]




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