Arrangement, crosswise

Applications of gel-spun PE Many applications overlap with those of aramid. Polyethylene has the advantage of its lower density and often a higher tenacity. This is important in ballistics and protective clothing, where Dyneema and Spectra find wide application. A special feature in armored plates is the Spectra Shield or Dyneema UD constmction arrangements of filaments in unidirectional layers bonded by thermoplastic layers in between the UD layers are arranged crosswise. This constmction is more effective than woven stmctures in ballistic protection. 

Crosswise Airflow that takes place from one side of a space to the other. This may be achieved by one or more jets or by allowing the air to enter the whole of one side surface and extracting the air by the whole area of the opposite side. The latter arrangement provides a piston effect, ensuring good air and contaminant transport. 

Figure 15.2 Crosswise arrangement of trans-but-2-ene molecules in ZSM-57 pores giving rise to the formation trans-3,4-dimethylhex-2-ene views along ten-ring (above) and eight-ring (below) channels.

In the cage type crystal structures, the a-cyclodextrin molecules are arranged such that the apertures are blocked on both ends by contiguous molecules. Two different forms of cage structures occur, one with a herring-bone-like, crosswise displacement of the a-cyclodextrin molecules, the other with the a-cyclodextrin molecules opposite, face to face to each other and displaced such that one molecule overlaps the neighbour below and therefore closes up its aperture. Figures 5a, b. 

Between two polarizers set crosswise to each other, the arrangement can be switched from dark to brig Because of the short switching time, which can be in the range of microseconds, this new generation of liquid crystals has attracted much attention in fundamental research and electrooptical applications. There has been considerable activity aimed at synthesizing new materials with large values of spontaneous polarization (PjJ and short electrooptical response tunes. 

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