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International symbols

Nuclear radiation is focused on harmful tissue, such as a cancerous tumor, to selectively kill or shrink the tissue in a technique known as radiation therapy. This application of nuclear radiation has saved millions of lives—a clear-cut example of the benefits of nuclear technology. The inset shows the international symbol indicating an area where radioactive material is being handled or produced. [Pg.113]

Table 2.5. Abbreviated International symbols and Schonflies notation. Table 2.5. Abbreviated International symbols and Schonflies notation.
Schonflies symbol Full International symbol Abbreviated symbol... [Pg.37]

In each column, the symbol for the point group is given in International notation on the left and in Schonflies notation on the right. When n = 2, the International symbol for D2h is mmm. When n is odd, the International symbol for C v is nm, and when n is even it is nmm. Note that n = n/2. In addition to these groups, which are either a proper point group P, or formed from P, there are the three cyclic groups 1 or Ci = E, 1 or Q = EI, and morCs = E a. ... [Pg.40]

Crystal system Schoenflies symbol International symbol Crystal system Schoenflies symbol International symbol... [Pg.17]

Crystal system International symbol Schoenflies symbol ... [Pg.18]

The symbol above is the international symbol representing the risk of radioactivity in an area or a material. [Pg.60]

Table 9.3.8. The order of positions in the international symbols for point groups and space groups... Table 9.3.8. The order of positions in the international symbols for point groups and space groups...
Index, full international symbol, lattice vectors, and conventional symbol. [Pg.327]

It is important to study two-dimensional (2D) symmetry because of its applicability to lattice planes and the surfaces of three-dimensional (3D) solids. In two dimensions, a lattice point must belong to one of the 10 point groups listed in Table 1.3 (by the international symbols) along with their symmetry elements. This group, called the two-dimensional crystallographic plane group, consists of combinations of a single rotation axis perpendicular to the lattice plane with or... [Pg.22]

TABLE 1.3 The 10 Two-Dimensional Crystallographic Plane Point Groups and Their Symmetry Elements (International Symbols) ... [Pg.23]

Figure 7.18 shows the information provided by the International Tables for X-Ray Crystallography, Volume I (and also the newer Volume A) for that most frequent and popular of space groups for organic crystals, P2i /c. The top line in Fig. 7.18 identifies the crystal system (monoclinic), the full international symbol (P 1 2 /c 1), which says that the lattice is primitive (P), that along the... [Pg.410]

One has to take into account, however, that the unit cell which is relevant for spectroscopy is the primitive (or Wigner-Seitz) unit cell. It is a parallelepiped from which the entire lattice may be generated by applying multiples of elementary translations. Face- and body-centered cells are multiple unit cells. The content of such a cell has to be divided by a factor m to obtain the content of a primitive unit cell. This factor m is implicitly given by the international symbol for a space group P and R denote primitive cells (m = 1), face-centered cells are denoted A, B, C (m = 2), and F m = 4), and body-centered cells are represented by I m = 2). Examples are described by Turrell (1972). [Pg.53]

Mark all glassware, trays, bench work areas, etc., with tape incorporating the international symbol for radioactivity (Fig. 35.3). [Pg.242]

Numerals in the international symbols of the center of inversion and all inversion axes are conventionally marked with the bar on top and not with the dash or the minus sign in front of the numeral (see Table 1.4). The dash preceding the numeral, however, is more convenient to use in computing for the input of symmetry data, for example, -1, -3, -4, and -6. [Pg.13]

Since every unit cell in the crystal lattice is identical to all others, it is said that the lattice can be primitive or centered. We already mentioned (Eq. 1.1) that a crystallographic lattice is based on three non-coplanar translations (vectors), thus the presence of lattice centering introduces additional translations that are different from the three basis translations. Properties of various lattices are summarized in Table 1.13 along with the international symbols adopted to differentiate between different lattice types. In a base-centered lattice, there are three different possibilities to select a pair of opposite faces, which is also reflected in Table 1.13. [Pg.36]

Centering of the lattice Lattice points per unit cell International symbol Lattice translation(s) due to centering... [Pg.37]

The symbol of the screw axis is constructed as Nk to identify both the order of the axis (N) and the length of the translation (k). Thus, the two three-fold screw axes have symbols 3i and 32, whereas the only possible two-fold screw axis is 2]. The International symbols, both text and graphical, and the allowed translations for all crystallographic screw axes are found in Table 1.16. [Pg.42]

Full international symbols of crystallographic space groups... [Pg.56]

One of the main subjects of the Hermetica is medicine, and in a series of texts Hermes instructs Asclepius, the semi-divine healer of Greek mythology. The Staff of Asclepius, a stick with a snake winding up it, is the international symbol for medicine, and Hermes Caduceus, with two snakes, has also become widely used as a medical symbol. The perfect equihbrium symboHsed by the Caduceus is the aim of aU hoHstic medicine. Thus all alchemists, as Sons and Daughters of Hermes consider themselves healers, and often refer to the Stone itself as the Universal Medicine. Jabir Ibn Hayyan [721-815], Michael Maier [1568-1622], and Robert Fludd [1574-1670], were all notable physicians as well as legendary alchemists. [Pg.15]

Figure 14.2, the tri-foil is the international symbol for radiation. The symbol can be magenta or black, on a yellow (or sometimes white) background. [Pg.307]


See other pages where International symbols is mentioned: [Pg.99]    [Pg.100]    [Pg.51]    [Pg.52]    [Pg.12]    [Pg.16]    [Pg.288]    [Pg.12]    [Pg.36]    [Pg.39]    [Pg.267]    [Pg.318]    [Pg.320]    [Pg.409]    [Pg.418]    [Pg.242]    [Pg.13]    [Pg.57]    [Pg.496]    [Pg.242]    [Pg.37]    [Pg.25]   
See also in sourсe #XX -- [ Pg.17 ]




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Full international symbols of crystallographic space groups

Internal energy symbol

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