Orientation transversal

Current meters are hydrodynamic instruments with rotating vanes or buckets. The speed of their rotation is proportional to the flow velocity. The forerunners of current meters were the paddle wheels developed in the early 18 century. These were applied by Francesco Domenico Michelotti (1710-1777) in 1767, or by Pierre-Louis Du Buat (1734-1809) in 1786. There are two principal types of current meters, namely the screw and the cup types. The first was conceived by the famous British engineer Robert Hooke in 1783 to measure wind velocity with four vanes similar to a windmill. This type was developed by Reinhard Woltman (1757-1837) in 1790, Andre Baumgarten (1808-1859), Albert Ott (1847-1895), Alphonse Fteley (1837-1903) and Haskell, among many others. The other type meter has several cups on spokes rotating around an axis oriented transverse to the current. These anemometers were first applied around 1850 to measure wind velocities, and then were developed by Theodore Gunville Ellis (1829-1883), or William G. Price (1853-1928) to record flow velocity in rivers. 

Bonart was amongst the first to identify the orientation of the periodic microphase structure under tensile deformation. Bonart suggested that the hard domains are composed of laterally stacked HS. It was noted that in MDI polyether copolymers, the SS become fully extended along the stretch direction and begin to crystallize at strains of about 150%. In contrast, the HS were found initially to orient transverse to the stretch direction and ultimately to break up to allow orientation of the HS in the stretch direction [14], Similar observations were made by us on DBDI based materials [67], as shown in the following section. 

The recorded output was the dichroic difference, from which the orientation function (F ) could be calculated [140, 363], which is unity for perfect orientation in the stretch directions, -1 /2 for perfect orientation transverse to the stretch direction, and zero for random orientation. 

This is the basic rule of mixture and represents the highest Young s modulus composite, where all fibers are aligned in the direction of load. The minimum Young s modulus for a reasonable design (other than a preponderance of fibers being orientated transverse to the load direction) is the quasi-isotropic composite and can be approximated by... 

Torsion of oriented polymer sheets was undertaken by Raumann [14] to determine the shear compliances S44 and See for uniaxially oriented (transversely isotropic) low-density polyethylene. Torsion of oriented sheets can also be used to determine the shear compliances S44, 555 and See for sheets possessing orthorhombic symmetry. As this situation is more... 

Based on the micrograph in Figure 3, the following wear mechanisms can be listed (i) small matrix shear lips or cracks, oriented transversely to the scratch direction, (ii) first indication of fiber edge cracking, which primarily occurred at... 

Craze initiation occurs in regions where chains were oriented transversely to direction of stress (birefringence positive)... 

In a process developed by Hoechst-Celanese, a biaxially oriented film is produced by extruding an anisotropic dope consisting of a polymerization solution of a LCP and a suitable solvent. This film is oriented transversely to the extrusion direction to enhance the transverse strength, after which the film is solidified and the solvent removed. 

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