Folded growth

The rate minimum at TF p2 has been observed in a number of alkanes from C162H326 to C294H590 [34-37]. In alkane C294H590, where the crystallization rate from solution is sufficiently low for Tc2 p3 to be accessible, a crystallization rate minimum has been observed between the once-folded and twice-folded growth intervals [38,39]. A series of minima, including that at Tc3 F4, have been observed in C39oH782 (see Sect. 5.2). A weak minimum at t -1 2 has also been reported in the melt crystallization of a methyl-terminated PEO fraction [40]. 

Figure 31. The five-fold growth spiral on the surface of the Mutsure-jima phlogopite-lM, as revealed by multiple-beam interferometry (courtesy of I.

Figure 32. Schematic drawing of the interlaced pattern of the six homogeneous polytypes, resulting from the nx60° rotations of the five-fold growth spirals (modified after Endo 1968).

This species of algae is readily fertilized by iron in the water — iron that may have blown in from the Sahara Researchers have shown that ferocious storm systems scoop up dust and carry it across the Atlantic. They have linked the occurrence of these dust storms with a hundred-fold growth of Trichodesmium... 

The world consumption of polymers exceeded 100 million tons/year. Annual polymer consumption per capita ranges from less than 0.2 in one country to nearly 200 kg in another. There is a potential for ten-fold growth of the plastics industry. 

The introduction of bauxite as a filler in ultra-high molecular polyethylene (UHMPE) results in two-fold growth of the extra energy localisation regions dimension from D 4 (UHMPE) to Df 8 (UHMPE-bauxite). In addition the microhardness increases approximately twice (Figure 6.33). 

Polymer crystals form by the chain folding back and forth on itself, with crystal growth occurring by the deposition of successive layers of these folded chains at the crystal edge. The resulting crystal, therefore, takes on a platelike structure, the thickness of which corresponds to the distance between folds. 

The chain direction within the crystal is along the short dimension of the crystal, indicating that the molecule folds back and forth, fire hose fashion, with successive layers of folded molecules accounting for the lateral growth of the platelets. 

In an attempt to stimulate onshore production of synthetic quartz and piezoelectric devices in the 1970s, Brazil imposed an embargo on exports and ultimately raised the price several-fold for small quartz crystals used as the starting material for quartz growth. However, sources of suitable pure quartz were located in the United States and Canada, including vein and pegmatic deposits (1). Synthetic processes compatible with the natural U.S. quartz starting material from a variety of sources were developed, and U.S. production became relatively independent of imports (1). 

Figure 13.18 Ribbon diagram of the structure of human growth hormone. The fold is a four-helix bundle with up-up-down-down topology, and consequently there are two long cross-connections between helices A and B as well as between helices C and D. (Adapted from J. Wells et al., Annu. Rev. Biochem.

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