Orientation / orientational

The following information is a continuation of what has been reviewed earlier in this chapter (PROCESSING AND PROPERTY, Orientation). Orientation consists of a controlled system of stretching heated plastic material (molecules) to improve their strength, stiffness, optical, electrical, and other properties. This process, which has been... 

In summary, therefore, processing, and in particular injection moulding, can introduce limited chemical degradation, local polymer orientation, orientation of short fibre reinforcements, internal stresses, warpage, shrinkage and defects such as weld lines and voids. 

Fig. 12.7 lllusrration of the idea of the random an infinite number of possibilities of interdomain dimer" model. For each molecule the orientation orientations in a dimer are shown, of a selected NH vector is indicated only three of... 

To prepare crystalline surfaces, usually the starting material is a suitable, pure, three-dimensional single crystal. From this crystal, a slice of the desired orientation is cut. Therefore the crystal must be oriented. Orientation is measured by X-ray diffraction. Hard materials are then grounded and polished. Soft materials are cleaned chemically or electrochemically. The surfaces are still mechanically stressed, contaminated, or chemically changed, e.g. oxidized. In principle, electrochemical processes in liquid can be used to generate clean crystalline surfaces. The problem is that an electrochemical setup is not compatible with an UHV... 

Infrared determination of orientation, orientation distribution, and crystallinity in polyethylene films. J. Polymer Sci. 24, 93—104 (1957). 

Figure 10 Experimental NRV S spectra of polycrystalline (powder, D (5)) and single crystal (in-plane, (v) and ont-of-plane, Dj. (v)) [Fe(TPP)(l-Mehn)(NO)]. Due to porphyrin packing in the f 2i2i2i space group, the in-plane orientation orients all porphyrin planes 13.8° from the incident beam. The out-of-plane orientation obtained by rotation of the crystal by 90° orients all porphyrin normals to within 13.8°...

First redraw the starting material and product so that they are in the proper conformation (s-cis for the diene) and mutual orientation. Orient the two so that the strongest electron donating group on the diene is in a 1,2- or 1,4-relationship with the strongest electron withdrawing group on the dienophile. Then draw the product with no stereochemistry indicated. 

To illustrate the effect of orientational dependence of the energy, Table 3 lists the S-null/6-31G(d) energy of the Ci molecule HOOF in three different orientations. Orientation I is the standard orientation, orientation II is obtained from the standard orientation by a rotation of 20° about the x-axis, and orientation in is obtained from the standard orientation by successive rotations of 20° about the x-axis and 30° about the y-axis. The energies are listed for two grids SG-1 and (20,50), which has 1000 points per atom, more typical of the coarser grids... 

Biaxial Orientation - Orientation in which the material is drawn in two directions, usually perpendicular to one another. Commonly used in films and sheets. See also Orientation. 

Orientation of particles Orientation vs. flow Orientation Orientation, molecular Ostromislensky Ostwald ripening Oxazoline compounds... 

A1 Minimum or no adhesion between the polymer and filler is present. Only the polymer matrix plays an active role during the deformation. Microscopic parameters which are averages (draw ratio, mean direction of orientation, orientation distribution function) are taken over the volume occupied by the polymer matrix. 

Orientation Orientation improves the inherent barrier and mechanical properties of unoriented nylon film. After biaxial orientation, nylon film exhibits a significant improvement in oxygen and aroma-barrier properties. ... 

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