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It coordinates

Since any DAC is defined by its coordinates P (Ai,S ) and the instrument sensitivity Gg f (reference gain) during DAC recording, any recalculation of the curve including the consideration of individual corrections (transfer loss, sound attenuation, etc.) is an easy task for modern PC based flaw detectors and does no longer burden the operator. [Pg.814]

Throughout, the space coordinates and other vectorial quantities are written either in vector fomi x, or with Latin indices k— 1,2,3) the time it) coordinate is Ap = ct. A four vector will have Greek lettered indices, such as Xv (v = 0,1,2,3) or the partial derivatives 0v- m is the electronic mass, and e the charge. [Pg.159]

The two coordinates that define the plane in which the loop located were discussed in Section n. In loops that encircle a conical intersection, there is always at least one phase-inverting reaction—we can choose its coordinate as the phase-inverting one. Let us assume that this is the reaction connecting A and... [Pg.348]

For both types of orbitals, the coordinates r, 0, and (j) refer to the position of the electron relative to a set of axes attached to the center on which the basis orbital is located. Although Slater-type orbitals (STOs) are preferred on fundamental grounds (e.g., as demonstrated in Appendices A and B, the hydrogen atom orbitals are of this form and the exact solution of the many-electron Schrodinger equation can be shown to be of this form (in each of its coordinates) near the nuclear centers), STOs are used primarily for atomic and linear-molecule calculations because the multi-center integrals < XaXbl g I XcXd > (each... [Pg.466]

Olefin synthesis starts usually from carbonyl compounds and carbanions with relatively electropositive, redox-active substituents mostly containing phosphorus, sulfur, or silicon. The carbanions add to the carbonyl group and the oxy anion attacks the oxidizable atom Y in-tramolecularly. The oxide Y—O" is then eliminated and a new C—C bond is formed. Such reactions take place because the formation of a Y—0 bond is thermodynamically favored and because Y is able to expand its coordination sphere and to raise its oxidation number. [Pg.28]

All terms in this equation have the units of moles moreover, in contrast to equation 60, the enthalpy rather than the entropy appears on the right-hand side. Equation 167 is a general relation expressing G/RT as a function of all of its coordinates, T, P, and mole numbers. Because of its generaUty, equation 167 may be written for the special case of an ideal gas ... [Pg.495]

Boric oxide is an excellent Lewis acid. It coordinates even weak bases to form four-coordinate borate species. Reaction with sulfuric acid produces H[B(HSO 4] (18). At high (>1000° C) temperatures molten boric oxide dissolves most metal oxides and is thus very corrosive to metals in the presence of oxygen. [Pg.189]

K2Cr(02)4, is obtained as stable red-brown crystals when H2O2 is added to a basic solution of K CrO maintained at 0°C (64). The geometry of Cr(V) in these crystals is dodecahedral, and its coordination number is 8 (63). [Pg.136]

In the preceding paragraphs we have analysed the behaviour and characteristics of a system when grounded or left isolated. The ground fault factor (GFF) plays a very significant role in the selection of insulation level (BIL) and its coordination with the different equipment connected on the system. The application of a particular method of grounding would thus depend upon... [Pg.668]

Let s continue with system curves. Up to this point, all elevations, temperatures, pressures and resistances in the drawings and graphs of systems and tanks have been static. This is not reality. Let s now consider the dynamic system curve and how it coordinates with the pump curve. [Pg.110]

Molar diagram A plot of the thermodynamic properties of a substance that has specific enthalpy as one of its coordinates. [Pg.1460]

Even the H atom itself can form compounds in which its coordination number (CN) is not just 1 (as expected) but also 2, 3, 4, 5 or even 6. A rich and unexpectedly varied coordination chemistry is thus emerging. We shall deal with the H atom first and then with the H2 molecule. [Pg.44]

Pressure is another important variable in the formation of feldspars and at sufficiently high pressures there is a tendency for A1 to increase its coordination number from 4 to 6 with consequent destruction of the feldspar lattice. For example ... [Pg.357]

The distinction between the first member of the group and the two heavier members, which was seen to be so sharp in the early groups of transition metals, is much less obvious here. The only unsubstituted, discrete oxoanions of the heavier pair of metals are the tetrahedral [Ru 04] and [Ru 04]. This behaviour is akin to that of iron or, even more, to that of manganese, whereas in the osmium analogues the metal always increases its coordination number by the attachment of extra OH ions. If RUO4 is dissolved in cold dilute KOH, or aqueous K2RUO4 is oxidized by chlorine, virtually black crystals of K[Ru 04] ( permthenate ) are deposited. These are unstable unless dried and are reduced by water, especially if alkaline, to the orange... [Pg.1082]

A simplified reaction scheme is shown in Fig. 26.5 Again, the ability of rhodium to change its coordination number and oxidation state is crucial, and this catalyst has the great advantage over the conventional cobalt carbonyl catalyst that it operates efficiently at much lower temperatures and pressures and produces straight-chain as opposed to branched-chain products. [Pg.1135]

A parabola is the set of points that are equidistant from a given fixed point (the focus) and from a given fixed line (the directrix) in the plane. The key-feature of a parabola is that it is quadrilateral in one of its coordinates and linear in the other. [Pg.53]

The Cu(NH3)42+ ion is commonly referred to as a complex ion, a charged species in which a central metal cation is bonded to molecules and/or anions referred to collectively as ligands. The number of atoms bonded to the central metal cation is referred to as its coordination number. In the Cu(NH3)42+ complex ion—... [Pg.409]

The formulated principals correlating crystal structure features with the X Nb(Ta) ratio do not take into account the impact of the second cation. Nevertheless, substitution of a second cation in compounds of similar types can change the character of the bonds within complex ions. Specifically, the decrease in the ionic radius of the second (outer-sphere) cation leads not only to a decrease in its coordination number but also to a decrease in the ionic bond component of the complex [277]. [Pg.116]

The first point of zero slope on the curve (point C) is identified with material yielding and so its coordinates are called the yield strain and stress (strength) of the material. The yield strain and stress usually decrease as temperature increases or as strain rate decreases. The final point on the curve (point D) corresponds to specimen fracture. This represents the maximum elongation of the material specimen its coordinates are called the ultimate, or failure strain and stress. Ultimate elongation usually decreases as temperature decreases or as strain rate increases. [Pg.52]

Many reactions are known which involve the sulfur atom in sulfoxides and other tricoordinate S(IV) species. Three situations are common in these reactions, i.e. the sulfur atom may remain tricoordinate, its coordination number may be reduced to two, or it may be increased to four. If the sulfur atom is rendered dicoordinate, it can no longer be stereogenic so such transformations will not be considered here. Reactions which leave the coordination number at three usually take place with inversion of configuration or... [Pg.80]

On the basis of the dipole moment, Paik, values computed from the Helmholtz equation (2.21) and the alkali ion radius one can estimate the effective positive charge, q, on the alkali adatom, provided its coordination on the surface is known. Such calculations give q values between 0.4 and 0.9 e (e.g. 0.86e for K on Pt(lll) at low coverages) which indicate that even at very low coverages the alkali adatoms are not fully ionized.6 This is confirmed by rigorous quantum mechanical calculations.27,28... [Pg.27]

The Number of Polyhedra with a Common Corner. The Electrostatic Valence Principle.—The number of polyhedra with a common corner can be determined by the use of an extended conception of electrostatic valence. Let ze be the electric charge of a cation and v its coordination number. Then the strength of the electrostatic valence bond going to each comer of the polyhedron of anions about it is defined as... [Pg.289]


See other pages where It coordinates is mentioned: [Pg.476]    [Pg.140]    [Pg.177]    [Pg.286]    [Pg.291]    [Pg.318]    [Pg.6]    [Pg.25]    [Pg.127]    [Pg.597]    [Pg.882]    [Pg.1079]    [Pg.1089]    [Pg.1134]    [Pg.1134]    [Pg.1215]    [Pg.1246]    [Pg.30]    [Pg.152]    [Pg.258]    [Pg.344]    [Pg.118]    [Pg.213]    [Pg.303]    [Pg.230]    [Pg.15]    [Pg.300]    [Pg.303]    [Pg.838]   
See also in sourсe #XX -- [ Pg.189 , Pg.191 ]




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