Core penetration

A fiber rotating band and a plastic obturator are assembled on the outside of the proj near the base of the sabot. During proj flight, the tracer burns for a minimum of 2.5 seconds. The sabot discards upon leaving the gun muzzle (with velocity of 4850fps) by setback, centrifugal and air-pressure forces. The sheathed core penetrates the target by kine-... 

Ternary moments are generally associated with greater quantum corrections than binary moments, Tables 5.2 and 6.3. Quantum corrections are most significant near the repulsive core of the interaction potential. Apparently, for three-body interactions, core penetration is more significant spectroscopically than for two-body interactions. 

In the first two chapters we have seen that the Na atom, for example, differs from the H atom because the valence electron orbits about a finite sized Na+ core, not the point charge of the proton. As a result of the finite size of the Na+ core the Rydberg electron can both penetrate and polarize it. The most obvious manifestation of these two phenomena occurs in the lowest states, which are substantially depressed in energy below the hydrogenic levels by core penetration. Core penetration is a short range phenomenon which is well described by quantum defect theory, as outlined in Chapter 2. 

The 10% difference is probably due to core penetration in the 4snf states, which is not taken into account, and, according to the theoretical work of Vaidyanathan and Shorer12 should be of the same approximate size as the discrepancy. In any case, it is clear that the nonadiabatic core polarization model reproduces the observed intervals quite well, while the adiabatic model is substantially in error. 

Fig. 19.9 Plot of scaled total decay rates n3r of Ba 6pmn( J = l + 1 autoionizing states in atomic units vs (. For ( = 0-4 the measured rates (O) shown are the average rates from many n values. The data for the rates for > 4 are for n = 12. The solid line is a simple theoretical calculation based on the dipole scattering of a hydrogenic Rydberg electron from the 6p core electron. Note that the core penetration of the lower states reduces the actual rate from the one calculated using the dipole scattering model. The constant total decay rate for > 8 is the spontaneous decay rate of the Ba+ 6p state (from ref. 39).

These processes are covered in other chapters of this text and will not be described herein. Factors such as substrate size, size distribution, shape, porosity, friability, and solubility may influence the release properties of the coated dosage form. The goal in coating is to apply the film in such a way that its release is governed by the intrinsic properties of the film, and not imperfection (core penetration, surface pores and defects, fines imbedded in the film, non-uniformity of distribution, etc.). In addition to the properties of the substrate and the coating material, the type of process selected may have a significant impact on the behavior of the finished product. 

The H-15D core penetrates the Michigan Formation, Marshall Sandstone, and Coldwater Shale (Fig. 2). The Marshall portion of the core includes a section of medium-coarse sand near its top (23.8 to 35.7 m depth), and a larger section below of interbedded sandstone, siltstone, and shale, including minor sections of black shale. The LP-1 core contains a thicker sand-dominated sequence of Marshall Sandstone (43.3 to KB.6 m depth), and below that, in the lower portion of the core, consists of interbedded sand, silt and clays, that includes the contact with Coldwater Shale (Fig. 2). The cores... 

Kinematical relativistic effects are caused by the fact that in the vicinity of the nucleus the electrons acquire high velocities, at a substantial fraction of the velocity of light. The direct influence of the relativistic kinematics (the so-called direct relativistic effect) is thus largest in the vicinity of the nucleus. However, as far as their impact on chemistry is concerned, relativistic effects are most important in the valence shells, which despite the small velocities of outer electrons are still strongly affected by relativistic kinematics (Schwarz et al. 1989). In particular, valence s and p orbitals possess inner tails they are core-penetrating orbitals, which means that there is a nonvanishing probability of finding their electrons close to the nucleus and thus... 

Many properties in a Rydberg series scale in different ways. For example, the level spacing scales as n -1/3, which turns out to be an essential property when we come to discuss K-matrix theory in chapter 8. The same is true for core penetration, and all the properties which depend on the overlap between the core and excited electron wavefunctions (see chapters 4 and 6). The size of Rydberg states (discussed in section 2.14) scales as n 2, while transitions between adjacent levels in the Rydberg manifold, which depend on the overlap between adjacent excited states, scale as n 4. Yet more scaling rules for Rydberg series in external fields will emerge in chapter 10. 

A much longer core (17.48 m) was recovered from Lake Vanda by the Dry Valley Drilling Project at site 4A in the deepest part of the lake (Cartwright et al. 1974). The core penetrated the entire section of sediment and included 5.06 m of granitic basement rocks at the bottom overlain by 12.42 m of unconsolidated sediment. The stratigraphy of the sediment in Fig. 19.33 includes 6.68 m of marine deposits at the base (M), followed by glacial sand and gravel (2.22 cm) (G), and lacustrine deposits (L) at the top (3.52 cm). 

Jakubek, Z.J., Field, R.W. Core-Penetrating Rydberg Series of BaF Single-State and Two-State Fits of New Electronic States in the 4.4 [Pg.90]

The phenomenon of core penetration is evidently a many-body effect, and its treatment is far beyond the scope of the present work. Thus we only note that since core penetration effects reflect the probability of finding the valence electron at the ionic core, the center of the atom, they scale as n reflecting the normalization of the wave function of the valence electron at the core. 

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