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Spacial distribution

The spacial distribution of electron density in an atom is described by means of atomic orbitals Vr(r, 6, (p) such that for a given orbital xp the function xj/ dv gives the probability of finding the electron in an element of volume dv at a point having the polar coordinates r, 6, 0. Each orbital can be expressed as a product of two functions, i e. 0, [Pg.1285]

M Era, J Koganemaru, T Tsutsui, A Watakabe, and T Kunitake, Spacial distribution of electroluminescence from oriented phenylenevinylene oligomer Langmuir-Blodgett film, Synth. Met., 91 83-85, 1997. [Pg.478]

Brindley and Sempels (1), Vaughan et al. (2) and Shabtai (3) have shown that the experimental conditions of Al intercalation influences the physicochemical properties of the clay. The nature, amount and spacial distribution of the pillars change the thermal stability, texture and acidity of the pillared clays. For example, Rausch and Bale (4) have reported that the OH/Al ratio modifies the structure of the Al complex and that monomeric [Al(0H)x(H20)6-x] " or polymeric [A1i304(0H)24(H20)i2] species can be obtained. Clearfield (5) demonstrated that the polymerisation state of Zr species depends on the temperature, concentration and pH of the solutions. In any case, the height of pillars is largely controlled by the polymerisation state of the intercalated complexes. However, in order to maintain the accessibility of the inner surface, the density or spacial distribution of the pillars has to be controlled. This parameter has been studied by Flee et al (5), and Shabtai et al (7) for Al pillared clays and Farfan-Torres et al (8) for zirconium. [Pg.97]

In multiphase filled polymer compositions, which may contain mixed filler types, combinations of fillers and fibres, or proportions of filler and a secondary modifying polymer, such as an elastomer, the spacial distribution of the phases has a direct bearing on the properties of the composite. In the case of the last mentioned system, the rubber may encapsulate the filler, be present as discrete droplets within the thermoplastic matrix or co-exist in both structural forms [80,81]. [Pg.179]

Here, pe is the local electric charge density in C/m3. With the Poisson equation, the potential distribution can be calculated once the exact charge distribution is known. The complication in our case is that the ions in solution are free to move. Before we can apply the Poisson equation we need to know more about their spacial distribution. This information is provided by Boltzmann5 statistics. According to the Boltzmann equation the local ion density is given by... [Pg.43]

The results indicate that efforts to utilize scattered radiation should be directed toward research in spectral selective devices with less concern for the spacial distribution. [Pg.412]

M. von Smoluchowski (1903) ° studied this problem of "irregularity from several angles in connection with the following problem Consider the deviations from the "most probable spacial distribution which the molecules of a gas in thermal equilibrium show at various times. What is the effect of these deviations on the equation of state and the F-value Smoluchowski in this paper referred to the relationship of this problem to the stability limit for a superheated fluid and supercooled vapor, which he investigated more closely in a later paper (1907).s ... [Pg.66]

By introducing the suitable Boltzmann assumptions for njj e (0) and p(0) into Bq. (54), one finds that the potential difference over the boundary layer is essentially proportional to a difference between two energy quantities, customarily referred to as electron affinity Of the chemisorbing gas. The potential variation as well as the spacial distribution of defects in the boundary layer can be calculated by integrating the Poisson equation ... [Pg.465]

Figure 2 shows the spacial distribution of the droplet temperature at diflFerent normalized times, t/ttotai, where ftotai is the total vaporization time. The bracketed term in Figure 2 is the fractional amount of fuel that has vaporized, which sometimes is a more meaningful measure for the duration of a phenomenon during droplet vaporization. After vaporization is initiated, the thermal wave reaches the droplet center only after a substantial time lag. A uniform temperature profile is not achieved until near bum-out. [Pg.11]

Fig. 4. Spacial distributions of the strength of the correlations as calculated by the correlated motion coefficient CMi(2.0,5.0) for all atoms. The circle at the right-hand side of the figure denotes the size of the cut-off radius r, which is chosen here to be 2.0 Fig. 4. Spacial distributions of the strength of the correlations as calculated by the correlated motion coefficient CMi(2.0,5.0) for all atoms. The circle at the right-hand side of the figure denotes the size of the cut-off radius r, which is chosen here to be 2.0 <ti. All circles in different graduation and in different size represent the initial positions of all atoms of the simulation cell. The graduation is made according to the values of C.V/,, divided into five classes the darker the graduation is, the larger the value of CM is obtained. Both X-and Y-coordinates are in units of (T. ...
As with the previous work, the influence of the liquid height and of the input power at the transducer on the spacial distribution of the mass transfer coefficient in the liquid were studied. Typical results are shown in Figures 27 and 28 where kd is plotted against x (y = 0). It can be seen that at very low input power (< 20 W) a standing wave pattern is observed but this rapidly disappears as the power exceeds 20 W. This behavior is almost certainly due to acoustic streaming and the formation... [Pg.42]

Winterbon, K.B., Sigmund, P., Sanders, J.B. Spacial distribution of energy deposited by atomic particles in elastic collisions. Mat. Fys. Medd. Dan. Vidensk. Selsk. 37(14) (1970)... [Pg.47]

The spacial distribution of intensities of light scattered by disperse system (Fig. V-19) can thus be described by the surface of rotation of sin2(p function around the (p=0 axis (bagel without a hole). The cross-sections of this surface by planes yield indicatrixes of the scattered light. [Pg.396]

An important factor in understanding both the strengths and the spacial distribution of a set of chemical bonds is the electronic condition of the central atom when it has—hypothetically—been promoted from its ground state to a state in which it is fully ready to form the set of bonds. Actually each atom in the molecule, whether central or peripheral, should be considered to undergo a promotion to a valence state, but it is usually the central atom that is of greatest concern. [Pg.85]

Fig. 37C.8. Spacial distribution of Gd, In, and Tm in a Tm203-graphite pellet. Adapted from Griffith et al. (1971). Fig. 37C.8. Spacial distribution of Gd, In, and Tm in a Tm203-graphite pellet. Adapted from Griffith et al. (1971).
TEM is a very common analytical technique that can produce high resolution photographs of nanoparticles in polymer matrices. This technique can yield accurate information on the level of exfoliation, the distance between partieles, and the spacial distribution of nanoparticles. Figure 3.4 contains the TEM image of a well-exfoliated composite of montmoril-lonite in nylon 6. The clay plates appear as dark lines in a light gray matrix. The teehnique can also yield pictures of tactoids and disordered structures mentioned previously when discussing X-ray diffraction. [Pg.27]

Fuel dissemination in terms of "blob" size, spectral and spacial distribution. [Pg.245]


See other pages where Spacial distribution is mentioned: [Pg.244]    [Pg.60]    [Pg.169]    [Pg.189]    [Pg.180]    [Pg.194]    [Pg.48]    [Pg.396]    [Pg.412]    [Pg.106]    [Pg.16]    [Pg.48]    [Pg.419]    [Pg.528]    [Pg.98]    [Pg.735]    [Pg.433]    [Pg.199]    [Pg.642]    [Pg.534]    [Pg.167]    [Pg.120]    [Pg.62]    [Pg.245]   
See also in sourсe #XX -- [ Pg.30 ]




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