Crystal texture

Gray GW, Goodby JWG (1984) Smectic Liquid Crystals, Textures and Structures. Blackie, Glasgow... 

Here we examine models that try to explain how textures develop during deposition on oriented (single-crystal), textured, polycrystalline, and amorphous substrates. We select electrodeposition of nickel as a model system. 

Figure 7.1. Categories of smectic liquid crystals. From Smectic Liquid Crystals, Textures and Structures, Gray, G.W. and Goodby, J.W.G. 1984 (Leonard Hill, Glasgow). (Reproduced by kind permission of the authors and publishers.) Side elevation and plan representation of molecular ordering in each of the smectic modifications. Triangles or arrows are used to represent tilt direction.

G. W. Gray and J. W. G. Goodby, Smectic Liquid Crystals—Textures and Structures, Leonard Hill, Glasgow and London, 1984. 

Figure 3. Liquid-crystal textures of the methyl-substituted model ester viewed through crossed polarizers, a, Smectic C-to-nematic transitional phase and b, smectic mosaic texture at 160 °C. Original magnification, 320x.

Gray GW, Goodby JW (1984) Smectic liquid crystals - textures and structures. Leonard Hill,... 

In this chapter we have considered three-dimensional ceramic constructions and nature s three-dimensional crystalline structures and glasses. There are many similarities between the construction of a ceramic work of art and the construction of a crystalline solid or glass. In both cases, units are built into a structure. The units are bonded together in a variety of ways. Both can result in pleasing works for the viewer to enjoy. A quartz crystal, made of silicon dioxide (Si02), can be just as beautiful as a carefully crafted ceramic piece. Particular elements of design make these objects beautiful. When considering ceramic pieces and natural crystals, texture is an important element. 

Gabriel, J.C.P., Sanchez, C. and Davidson, P. (1996) Observation of Nematic Liquid-Crystal Textures in Aqueous Gels of Smectite Clays. The Journal of Physical Chemistry 100, 11139-11143... 

Liquid crystal textures were observed by optical microscopy between crossed polars. The instrument used was an Olympus BH-2 polarizing microscope equipped with a Linkam TH-600RH hot stage. 

In the past there have been several attempts to investigate the relationship between structure and mechanical properties in polyethylene. It has proved possible to produce samples of the polymer with a single-crystal texture ( ) but they are still polycrystalline and certain ambiguities remain concerning the detailed deformation mechanisms in such samples (9 ). There have also been reports of studies of the deformation of single crystals of polyethylene on extensible substrates (10,11). Because the polymer... 

For comprehensive descriptions of the structure and properties of liquid crystals and leading references, see (a) F. D. Saeva (Ed.), Liquid Crystals. The Fourth State of Matter, Marcel Dekker, Inc., New York, 1979 (b) H. Kelker and R. Hatz, Handbook of Liquid Crystals, Verlag Chemie, Weinheim, 1980 (c) G. W. Gray and J. W. Goodby, Smectic Liquid Crystals. Textures and Structures, Leonard Hill, Glasgow, 1984. 

Polarizing optical microscopy is often the method of first choice. It was with POM that the textures of liquid crystals were observed and the classification of liquid crystals was first made according to these observations. In this field, two books are recommended The Textures of Liquid Crystals by Demus and Richter (1978) and Smectic Liquid Crystals — Textures and Structures by Gray and Goodby (1984). While the latter provides readers with a practical and useful experimental guideline to the textures and classification of smectic liquid crystals of different polymorphic types together with as many as 124 reference photographs of typical textures, the former... 

Gray G W and Gccdby J G W1984 Smectic Liquid Crystals Textures and Structures (Glasgow Hill)... 

Gray, G. W. Goodby, J. W. Smectic Liquid Crystals Textures and Structures Leonard Hill Glasgow, 1984. 

For both crystal texture improvement and work function engineering SAMs are particularly favorable and straightforward to handle. When deposited under the right conditions, they selectively attach only to the electrodes and selflimit their growth to one monolayer. This allows for straightforward deposition without the need for any additional lateral patterning or precise application to limit the layer s thickness. 

Bartczak, Z., Argon, A. S., and Cohen, R. E. (1992) Deformation mechanisms and plastic resistance in single-crystal textured high density polyethylene, Macromolecules, 25,... 

Polarized IR spectroscopy was employed by Wu et al. to investigate crystallinity, the formation of different crystal orientations and the crystal texture of syndiotactic PS (sPS) crystallized inside AAO hard templates while in contact with a bulk reservoir of the same polymer [101]. The 6-polymorph was obtained by cooling from the melt to 260 °C and crystallizing at this temperature for 2 h, while heating amorphous samples quenched from the molten state to 240 °C and heating to this temperature for 2h resulted in the formation of the or-polymorph. A comparison of the areas of peaks... 

DESCRIPTION OF AN INNOVATIVE GC METHOD TO ASSESS THE INFLUENCE OF CRYSTAL TEXTURE AND DRYING CONDITIONS ON RESIDUAL SOLVENT CONTENT IN PHARMACEUTICAL PRODUCTS... 

Application Influence of crystal texture and drying conditions on RS content... 

Among all parameters influencing RS content, crystal texture is of utmost importance. It is evident that a crystal exhibiting a porous texture will enable the easy escape of a solvent while a compact and dense crystal will retain the solvent inside its structure whatever the type of particles monocrystalline (i.e., monoparticular) or polycrystalline . The term polycrystalline particles will be employed to designate elementary particles that can be composed of agglomerates, spherolites or spherical crystals according to Kawashima. ... 

With this example we can clearly point out that the crystal texture is a determining factor in the complete escape of the solvent when the crystalline texture is sintered-like, after the desolvation of solvate crystals, progressive drying is necessary to prevent the crusting phenomenon. 

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