Lateral correlation

Mesomorphic forms characterized by conformationally ordered polymer chains packed in lattices with different kinds of lateral disorder have been described for various isotactic and syndiotactic polymers. For instance, for iPP,706 sPP,201 sPS,202 syndiotactic poly(p-methylstyrene) (sPPMS),203 and syndiotactic poly(m -methylstyrene),204 mesomorphic forms have been found. In all of these cases the X-ray fiber diffraction patterns show diffraction confined in well-defined layer lines, indicating order in the conformation of the chains, but broad reflections and diffuse haloes on the equator and on the other layer lines, indicating the presence of disorder in the arrangement of the chain axes as well as the absence of long-range lateral correlations between the chains. 

Another magnitude that characterizes the surface morphology is the lateral correlation length, (L, t), which represents the typical width of these structures. DST applies to systems in which, depending on the temporal range, f (L, t) follows the expressions ... 

As a result, many correlations are available for heat and mass transfer at moderate pressures that have been developed over time. Perry and Green [6] give a fairly complete amount of data with regards to correlations for different arrangements [7], On the other hand, very few data and correlations are available in the field of high pressure heat and mass transfer, as will be reviewed later. Correlations are in terms of the individual coefficients, ki and h, included in dimensionless groups such as those given before in Eqns. (3.4-10). 

Levitan C, Ward PB, Catts SV. 1999. Superior temporal gyral volumes and laterality correlates of auditory hallucinations in schizophrenia. Biol Psych 46 955-962. 

On the basis of these conclusions it was perhaps surprising that a nonstereospecific synthesis of a heteroyohimbine should yield predominantly the presumed cis D/E isomer, ( )-ajmalicine, rather than the trans D/E isomer (60). However, later correlations by reliable chemical and physical methods proved beyond doubt that the earlier... 

The Taylor h rpothesis has been further discussed by [144] (pp 5-7) and [59] (pp. 31-81) considering theories of double correlations between turbulence-velocity components, the features of the double longitudinal and lateral correlations in homogeneous turbulence, integral scales of turbulence, and Eulerian, Lagrangian and mixed Eulerian-Lagrangian correlations. 

The term in front of the bracket is the well-known Kanazawa expression (Eq. 61). The correction terms inside the brackets take care of roughness at the interface of the hquid k is the lateral correlation length of roughness (where the spectriun of spatial frequencies is assiuned to be Gaussian), hr is the root-mean-square roughness, and 8 = 2r]l pco)) / is the penetration... 

Chemical evidence for the ketonic nature of pyroaconitine (CXLI), formed by p3Tolysis of aconitine, was demonstrated by subjecting it to Wolff-Kishner reduction (85). The product of this reaction contained no carbonyl absorption in its IR spectrum, showing that not only had the ketone been reduced but also that the benzoyloxy group had been saponified. Further, one of the methoxyl groups had been eliminated. The Wolff-Kishner product was thus assumed to possess structure CXLIII since it resisted catalytic hydrogenation. A later correlation involving... 

When the corrugation of the surface is not too large, i.e., the energy difference between the most favorable and the most unfavorable adsorption site is less than about 20% of the overall adsorption energy, it does not influence the density profile significantly in the direction perpendicular to the surface, in spite of the fact that substantial lateral correlations exist within the adsorbed layer of molecules. Weak correlations between favorable adsorption sites and preferred locations for molecules in the second layer have been observed (see Fig. 5 in Ref. 49). They are a consequence of the interactions between second-layer molecules and the molecules in the ordered adsorbate layer. 

Corrugation effects give rise to pronounced lateral correlations, which can also be characterized by the scatter plots shown in section 4.2. The corresponding PCFs have been investigated by Spohr [49] and Heinzinger [144, 145] for Pt(lOO) and by Bocker et al. [81] for mercury surfaces. 

A consideration of the paracrystalline distortions, primarily the limited lateral correlations of axial chain coordinates ( chain shift disorder ), is found in the paper by Kawaguchi and Petermann [174]. According to the analysis of their electron diffraction patterns of flow-oriented PPP films, the diffraction on the third and higher layer lines is essentially single-chain diffraction. Although indications for an off-meridional position of the (002) reflection are found in some patterns, the authors favour the orthorhombic unit cell. 

Fig. 8.52 The molecular structure of the triphenylene sulphur derivative HHTT and a sketch of its liquid-crystalline columnar H phase. The H phase exhibits long-range intracolumnar correlations and thus also a lateral correlation between the columns. Column 0 is shifted relative to columns 1 and 2 by p/2 and has the opposite helicity compared to columns 1 and 2.

One of the earliest works using HPLC-DAD for the identification of the large PAHs involved the analysis of a diesel particulate extract [16-18]. About a dozen LPAHs were found. The identifications made were later correlated to the observed mutagenicity of this diesel particulate. A carbon-black extract, obtained from the same carbon black was examined by HPLC-DAD. The DAD, as well as a much larger collection of standard compounds, allowed the identification of around 20 more LPAHs than in earlier studies of this same material. 

A similar observation of increasing A gx when the temperature is increased toward the haze point was made in a comprehensive study by Lang et al. [29]. The results were later correlated with the percolation phenomenon of microemulsions as revealed by conductivity measurements [33]. Surprisingly high values of the second-order exchange rate constant... 

Let us remark that in other theories the overcharging is due to lateral correlations between adsorbed PEs, which in conjunction with screening by salt ions leads to strongly overcharged surfaces [84,128). 

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