Orientation mono-axial

Orientation, uniaxial Also called axial orientation, mono-axial orientation, or UO.. This is the stretching only in one direction that is usually in the machine direction. 

Deliberately oriented polystyrene is available in two forms filament (mono-axially oriented) and film (biaxially oriented). In both cases the increase in tensile strength in the direction of stretching is offset by a reduction in softening point because of the inherent instability of oriented molecules. 

In addition to orientation in one direction (mono-axial orientation), biaxial orientation is possible. This is achieved when sheet is stretched in two directions resulting in layering of the molecules. This can increase the impact strength, tensile strength and solvent cracking resistance of polymers and with crystalline plastics the polymer clarity may also be improved. 

Orientation may be obtained deliberately by stretching the melt just before it is frozen mono-axial orientation is important for the production of fibres and filaments, and bi-axial orientation (that is, stretching both lengthwise and transversely to an equal extent) is essential for the qualities required of some... 

Where a is the unit vector defined by the local frame defining the axial quadupole, r is the vector oriented towards r from the monopole to the axial quadupole. Qa is the corresponding matrix element. Following the modification of the charge-dipole interaction, we introduced a modified mono-quad interaction, namely I -mono-quad1 ... 

A similar chelated TPP compound 60 was used by Walker to study the effect of axial ligand plane orientation on the H-NMR shifts of the pyrrole protons in iron(III) (TPP)bis(imidazole) cotnplexes In this case the tail was made shorter to study the effect of axial ligand bond strain. In addition. Walker and Benson have used mono-(o-aminophenyl)triphenylporphyrin (57) to prepare a series of derivatives 6la-e containing a pyridine ligand bound to a zinc TPP . H-NMR and visible spectroscopy were used to study the displacement of the 3-pyridyi ligand by free 3-picoline (Scheme 23),... 

In related work, Richter-Addo and coworkers reported a DFT study on a mono-metal heme model system of the proposed mono-heme hyponitrite intermediate by calculating the effects of addition of an electron or a proton to a six-coordinate (P)Fe(NONO)(Im) system (252). In their neutral (P)Fe(NONO)(Im) (theoretically obtained by coupHng via attack of NO on (P)Fe(NO)(Im)), two products, depending on the relative orientation of NONO and Im axial planes, namely [(P)Fe(NONO)(Im)] and [(P)Fe(NONO)(Im)] were calculated to have similar energies. The calculated N-N bond distances obtained for the models compounds were 1.960... 

Dipolar effects on GB discs have been studied for the case of axial dipoles [58], and coherent dipolar domains in the columns have been found, even if these mono-oriented domains do not comprise the whole colunm. This does not allow the formation of ferroelectric columnar systems [46], that indeed were not observed. 

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