Streak phase system

When dealing with the equatorial streak of a fibo- pattmi, it tqtpears suitable to extract the transverse structure /jj (s ). Through Fourier transformation relation this projection is linked to a two-dimensional two-phase system made ftom needle cross sections in a matrix, as indicated in the bottom row of fig 2. 

Figure 7. Proposed structure model of the cne-dlnEnsicaially ordered streak jhase, the second reconstructed phase observed with the H/Ni(110) system. Again, shaded circles represent Ni atoms of the second layer.

Eadie, in Ref 69, reports on a considerable amount of work done on the ability of beeswax and paraffin wax to remain coated on HMX surfaces when immersed in liq TNT. Thru measurements of contact angles, a technique used earlier on RDX/wax systems reported on by Rubin in Ref 23, it was determined that the TNT preferentially wets the HMX and the wax is stripped away. He concludes that the most important property of a desensitizing wax is that it should be readily dispersed uniformly thruout the TNT phase. He also suggests that a better desensitizer for investigation for use would be a wax or substituted hydrocarbon having a low interfacial tension with TNT. The smaller the wax droplet size the more efficiently it will be distributed and the more effectively it should desensitize. Williamson (Ref 64) in his examination of the microstructures of PETN/TNT/wax fusion-casts detected that wax is dispersed thru the cast as isolated descrete globules which he refers to as blebs or irregular or streak-like areas, surrounded by TNT (see also Ref 54)... 

Unidimensional TLC of nucleic acid derivatives has also been done on silica gel. Issaq et al. (1977) separated mixtures of alkylated guanines, adenines, uracils, and cytosines on silica gel 6OF2S4, in various chloroform-alcohol solvent systems. The addition of 1 ml of ammonium hydroxide to the mobile phase prevented streaking and resulted in nondistorted developed spots. Figueira and Ri-beiro (1983) separated adenine, adenosine, inosine, hypoxanthine, 2-AMP, 5-AMP, ADP, ATP, cAMP, and dibutyryl cAMP also on silica gel 6OF254, and Sleckman et al. (1985) used conventional and high-performance silica gel to separate four representative nucleotides and their corresponding nucleosides. Detailed Experiment 2 of this chapter describes a unidimensional separation of nucleotides and nucleosides on silica gel. 

In the regime L/p 1, the elastic theory considers the cholesteric medium as a system of equidistant (and thus parallel) layers and that the curvatrue distortions are predominant, (5.8). The description of defects such as edge dislocations, oily streaks, and focal conic domains in cholesterics is often based on the results obtained for simpler layered medium, namely, the smectic A phase. 

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