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Geometrical relationships

Comparing Eqs (4.1)-(4.3) with Eqs (4.4)-(4.6), it is seen that if shrinkage occurs the values are respectively one-half of those without shrinkage. [Pg.41]

If the dihedral angle is less than 180° as in real systems, the values of r are larger than those in Eq. (4.1) and Eq. (4.4). In the absence of shrinkage, r is calculated to be  [Pg.41]

2 Driving Force and Mechanisms of Sintering in thelwo-Particle Model [Pg.41]

Ys is the specific surface energy of the solid (solid surface energy), the [Pg.41]

1able 4.I. Material transport mechanisms during sintering  [Pg.42]


The actual work input coefficient, is written by taking the ideal work input coefficient, Equation 5.1, and modifying by the addition of the slip factor, SF. The geometric relationship of the Stodola slip function is shown in Figure 5-23. [Pg.155]

Figure 5-23. Geometric relationship of Stodola slip function. Figure 5-23. Geometric relationship of Stodola slip function.
One criterion of aromaticity is the ring current, which is indicated by a chemical shift difference between protons, in the plane of the conjugated system and those above or below the plane. The chemical shifts of two isomeric hydrocarbons are given below. In qualitative terms, which appears to be more aromatic (Because the chemical shift depends on the geometric relationship to the ring current, a quantitative calculation would be necessary to confirm the correctness of this qualitative impression.) Does Hiickel MO theory predict a difference in the aromaticity of these two compounds ... [Pg.545]

Esters and acetylated hydroxyl groups are completely stable under the experimental conditions, but with ketals 10 29,110,112 yields are generally observed in the thermal reaction. Double bonds do not seem to interfere seriously with the course of the reaction provided that the geometric relationship of the free hydroxyl group to the angular methyl group is not changed drastically. In some cases allylic acetoxylation occurs, e.g., at C-7 of A -steroids. ° Ketones are usually stable (especially under photo-lytic conditions) but occasionally a-acetoxylation has been observed. [Pg.242]

Fig. 1. (a) Geometrical relationship between incident electron beams in TEM and CNT, (b) typical TED pattern, (e) schematic illustration of image of CNT and (d) ero.ss-seetional view of CNT. In the TED pattern, the indexes follow those of graphite. [Pg.30]

In these acids the geometric relationship of the substituent X to the reactive site COOH approximates that in 4-substituted benzoic acids, but in 3 the resonance... [Pg.326]

The 1,3-dipolar cycloaddition reaction of nitrones with alkenes gives isoxazolidines is a fundamental reaction in organic chemistry and the available literature on this topic of organic chemistry is vast. In this reaction until three contiguous asymmetric centers can be formed in the isoxazolidine 17 as outlined for the reaction between a nitrone and an 1,2-disubstituted alkene. The relative stereochemistry at C-4 and C-5 is always controlled by the geometric relationship of the substituents on the alkene (Scheme 8.6). [Pg.321]

The heat transfer coefficient is correlated experimentally with the fluid transport properties (specific heat, viscosity, thermal conductivity and density), fluid velocity and the geometrical relationship between surface and fluid flow. [Pg.346]

A anmileue is a compound with three adjacent double bonds. Draw an orbital picture of a cumulene. What kind of hybridization do the two central carbon atoms have What is the geometric relationship of the substituents on one end to the substituents on the other end What kind of isomerism is possible Make a model to help see the answer. [Pg.288]

According to Equation 1-3, the x-ray power produced is 13 watts. The corresponding number of photons per second is 13/[ 1.2Af 10 l0)]7 or 10 5(1015). In an actual spectrograph, the geometrical relationship between source and sample will reduce the incident intensity to perhaps 1% of that at the source. Therefore,... [Pg.106]

Table 3. Geometrical Relationship Between the Different Structure Types MreMt4B4 (My = Co, Ru, Rh, Os, Ir)... Table 3. Geometrical Relationship Between the Different Structure Types MreMt4B4 (My = Co, Ru, Rh, Os, Ir)...
The mechanism of 1,3-dipolar cycloaddition can be found in Ref. 63 and the references within. The reaction of nitrone with 1,2-disubstituted alkenes creates three contiguous asymmetric centers, in which the geometric relationship of the substituents of alkenes is retained. The synthetic utility of nitrone adducts is mainly due to their conversion into various important compounds. For instance, P-amino alcohols can be obtained from isoxazolidines by reduction with H2-Pd or Raney Ni with retention of configuration at the chiral center (Eq. 8.44). [Pg.250]

Ruland [253] shows that in this case the integral transform Eq. (9.11) can be simplified and solved. The corresponding geometrical relationships are sketched in Fig. 9.5. [Pg.213]

In metalloproteins two paramagnets can be much farther apart, and so the dipolar interaction can be correspondingly weaker. Furthermore, the centers will usually each have significant g-anisotropy, and their local structures will differ and will have a complex mutual geometrical relationship. We therefore use the symmetric biradical as a simple model to obtain a first impression of the type of spectral patterns to be encountered. [Pg.183]

Molecule and associated Relationship between Geometric Relationship individual bond dipoles dipole moment(molecular)... [Pg.230]

Wier. Perhaps I can add a few things. The critical point is that the differences will be subtle in time course and difficult to predict on a theoretical basis, without knowing the exact geometrical relationship among the different sources. In striated muscle where we have better information on where sparks might arise, the calculations have shown that it is hard to distinguish a small, in-focus spark, from a large out of focus one. They may have the same amplitude. [Pg.170]

Copper bromide has been used by Srebnik and co-workers to homocouple vinyl zirco-nocenes 75, thereby providing access to 2,3-dibora-1,3-butadienes (e. g., 76 Scheme 4.45), which retain their original geometrical relationships [76], These dimerizations readily take place at room temperature the products are stable to both air and moisture and can be purified by column chromatography on silica gel. Prolonged heating of the product at 150 °C was found not to lead to decomposition or even isomerization. Similarly, precur-... [Pg.131]


See other pages where Geometrical relationships is mentioned: [Pg.1686]    [Pg.674]    [Pg.706]    [Pg.285]    [Pg.276]    [Pg.123]    [Pg.234]    [Pg.419]    [Pg.210]    [Pg.211]    [Pg.106]    [Pg.85]    [Pg.710]    [Pg.346]    [Pg.1018]    [Pg.65]    [Pg.81]    [Pg.740]    [Pg.17]    [Pg.345]    [Pg.4]    [Pg.67]    [Pg.450]    [Pg.30]    [Pg.321]    [Pg.63]    [Pg.119]    [Pg.11]    [Pg.28]    [Pg.97]    [Pg.162]    [Pg.89]    [Pg.87]    [Pg.153]   
See also in sourсe #XX -- [ Pg.257 ]




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