Influence of orientation

Y. T. Mazurenko and N. G. Bakhshiev, The influence of orientational dipolar relaxation on spectral, temporal and polarizational properties of luminescence in solutions, Opt. Spektrosk. 28, 905-913 (1970). 

Partidos C, Stanley C, Steward M. The influence of orientation and number of copies of T- cell and B-cell epitopes on the specificity and affinity of antibodies induced by chimeric peptides. Eur J Immunol 1992 22 2675. 

The investigation of electron ionization is clearly in the early stages in comparison with the electron transfer studies, and additional work on the influence of orientation on Augmentation will be required before a coherent pattern emerges and a model for fragmentation can be attempted. However, a simple model that considers ionization in terms of the Coulomb potential developed between the electron and the polar molecule, taking the electron transition probability into account, reproduces the main experimental features. This model accounts qualitatively for the steric effect measured and leads to simple, generally applicable, expressions for the maximum (70 eV) ionization cross section. 

Properties The influence of orientation on the properties is usually studied by investigating a so-called drawing series, i.e. a series of yams drawn with different draw ratios. 

Fig. 27 Influence of orientation in PMMA (Mn = 45200) induced by injection molding on...

Unfortunately the study of three faces of a germanium single crystal is the only one which has been made on the influence of crystal orientation on the oxidation of semiconductors. The authors feel that results on semiconductors will probably be similar to those reported here for other metals. It has not been possible in this paper to discuss many subjects such as adsorption, work function of the different faces, and surface diffusion, all of which are important for a complete understanding of the influence of orientation on oxidation. There is a scarcity of experimental data on these subjects and it is hoped that future experimentation will alleviate this situation. 

Most experiments do not depend on order parameters of higher rank, e.g. the influence of orientational order on an absorption band is completely described in terms of S and D (Luckhurst, 1993). On the other hand, Raman-spectra being based on a two-photon effect are influenced additionally by the order parameters of the next level, such as the Legendre polynomial P4 (Pershan, 1979). This is of considerable theoretical interest, however, up to now of less importance for practical applications. There are some further experimental techniques for gathering information on the orientational order, among these are fluorescence, neutron and electron scattering. Probably the most reliable method is NMR (Emsley, 1985), however this usually means deuteration of all hydrogen atoms but one. 

I.R., dielectric and calorimetric methods (15-20). Keratin exhibits a single line spectrum by N.M.R. with line-width depending on orientation. This is in contrast to collagen which shows a three line spectrum. Lynch and Haly (15) have studied the influence of orientation on the spin-spin relaxation time of absorbed water in keratin from rhinoceros horn. A priviledged rotation of the water is observed around an axis approximately parallel to the fiber direction. From I.R. results Bendit proposes a weak association of water with carbonyl groups in the crystalline phase. I.R. experiment on deute-... 

Success in correlating both thermal conductivity and viscosity by Thodos et al. pi.32] for the heavier diatomic molecules provides a basis for establishing the heavy-molecule end of the critical-point loci as nearly horizontal asymptotic lines. For the thermal conductivity no other good tie points exist, and the critical-point locus is therefore more conjectural. It is believed that a single critical point locus will adequately include all types of molecules. At the critical point the density is lower and hence the influence of orientational effects in two-body interactions will be smaller than at the triple point. Fortunately the effect of errors in locating the helium end of this locus is minimized with respect to predicting the behavior of the thermal conductivity for H2, D2, etc. The high-temperature ends of the He, He H2, D2, A, and N2 thermal conductivity curves were, in each case, extrapolated (broken lines) to their respective reduced critical temperatures. 

Angle between direction of measurement and direction of flow Fig. 68 Influence of orientation on shrinkage of glass fiber reinforced PBT [90], BASF AG... 

Theoretical explanations of orientation processes, and the influence of orientation on physical properties. 

Yoshida H, Miyata N, Naito K, Ishikawa S, Yamagishi C, Influence of orientation angle of fibre on mechanical properties in uni-directional and two-directional carbon fibre reinforced SiC composites, J Ceramic Soc Japan, 102(11), 1016-1021, 1994. 

Milicevic, D., Trifunovic, S., Popovic, M., VukaSinovic, T., Milic, Suljovrujic, E. The influence of orientation on the radiation-induced crosslinking/oxidative behavior of different PEs. Nucl. Instium. Meth. Phys. Res. B 260, 603-612 (2007)... 

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