Textures INDEX

Component of Optical Texture seen in Microscopy Abbreviation Size Optical Texture Index (0TI)... 

When Equation (51) was derived the correlation matrix of zf was considered diagonal because the symmetrized spherical harmonics are orthogonal. In practice some correlations exists [because only discrete points (O, P) and (T, y) are involved] but they are small. We can also calculate the texture index /and the texture strength According to Bunge the texture index is defined as follows ... 

To derive the right-hand side of Equations (52), (28) and Table 12.1 were used. Note that the texture index contributes not only to the refined coefficients but also the coefficients linearly correlated from the cubic groups and also... 

KEY WORDS citric acid, gypsum, mechanical properties, mechanism of sel retardation, microstnicture of retarded gypsum mortars, texture index, strength, creep properties... 

The alterations can be partly derived from Fig. 2. The figure shows the measured increase of the average circumferences U and areas F, and the decrease of the shape factor K and of the texture index Q above increased citric acid additions. More details of the experimental data are given elesewhere [2]. 

These in turn yield the texture parameter, Q, which according to Eq 3.14a and 3.14b is none other than A7A. The alternative texture index, (p, if needed, can then be obtained by solving Eq 3.15b. 

Antireflection coatings are used over the silicon surface which, without the coating, reflects ca 35% of incident sunlight. A typical coating consists of a single layer of a transparent dielectric material with a refractive index of ca 2, which is between the index of siUcon and ait or cover material. Materials such as titanium dioxide, tantalum pentoxide, Ta20, or siUcon nitride, Si N, ca 0.08-p.m thick are common. The coating and a physically textured... 

Easily observed physical properties of soils often are useful indexes of behavior. These index properties include texture and appearance, specific weight, moisture content, consistency, permeability, compressibility, and shearing strength [37,38]. 

Because the quality and health aspects of foods cannot be measured by a single index, it necessarily follows that the subject of control methods in the canned food industry is very broad, and includes chemical, physical, organoleptic, and bacteriological tests, only the first of which is discussed here. The measurement of color, odor, optical clarity, texture, viscosity, and chemical composition has been used to evaluate canned foods, but in many cases the methods that are applicable to one product are either not applicable to another, or can be used only after considerable modification. 

The metal surface is polycrystalline and has a rather complex profile. Because of different crystallite orientations at the surface, different crystaf faces are exposed, such as smooth fow-index faces and stepped high-index faces. Surface texture where a particufar kind of face is predominant can devefop in individual cases. Microcracks and various lattice defects (dislocations, etc.) will also emerge at the surface. 

Electron crystallography of textured samples can benefit from the introduction of automatic or semi-automatic pattern indexing methods for the reconstruction of the three-dimensional reciprocal lattice from two-dimensional data and fitting procedures to model the observed diffraction pattern. Such automatic procedures had not been developed previously, but it is the purpose of this study to develop them now. All these features can contribute to extending the limits of traditional applications such as identification procedures, structure determination etc. 

The purpose of indexing texture patterns is the geometrical reconstruction of the three-dimensional reciprocal lattice from the two-dimensional distribution of H spacings. One advantage of texture patterns is the possibility to determine all unit cell parameters of a crystal unambiguously and index all the diffraction peaks from only a single texture... 

The indexing is based on the direct relationship between the texture pattern and the reciprocal lattice. For a reflection hkl with the reciprocal lattice xector Hhki. ... 

Indexing a texture pattern is often rather complicated, but several characteristic features facilitate the indexation (see [142]). 

Figure 4. Indexing texture patterns from crystals of different symmetries (see the text for explanations). Assigning the indices to the reflections is shown in (a) - (c). The splitting of the reflections hkl for different symmetries is shown in (d) - (f). (a), (d) trigonal (lizardite IT), (b), (e) monoclinic (muscovite 2Mi). (c), (f) triclinic (kaolinite).

Here we will describe an example of data extraction during processing of texture pattern of brucite and show the results of indexing, determination of unit cell parameters and extraction of intensities. 

The results obtained in the present work show that the developed methods can be applied successfully to oblique texture electron diffraction patterns. The program TexPat has been designed to produce accurate lattice parameters and intensities. Indexing oblique texture electron diffraction patterns from structures with S5mrmetry lower than orthorhombic remains quite difficult task due to the geometrical properties of texture patterns. This difficulty is overcome by the introduction of semi-automatic algorithms for the indexing. 

Note 1 The nematic liquid crystal must have a negative dielectric anisotropy (Af < 0), and a positive anisotropy (Aa > 0). The optical texture corresponding to the flow pattern consists of a set of regularly spaced, black and white stripes perpendicular to the initial direction of the director. These stripes are caused by the periodicity of the change in the refractive index for the extraordinary ray due to variations in the director orientation. 

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