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Signature equation

In the microcanonical ensemble, the signature of a first-order phase transition is the appearance of a van der Waals loop m the equation of state, now written as T(E) or P( ). The P( ) curve switches over from one... [Pg.2267]

Resolution Resolution is the degree of spacing of visible frequency components in the vibration signature and is proportional to the bandwidth. The equation for resolution is given below ... [Pg.716]

Odd torque harmonics become significant as strain increases and are therefore considered as the nonlinear viscoelastic signature of tested materials, only available through FT rheometry. Figure 30.10 shows the typical pattern of corrected relative TTHC (i.e., T(nw/lw)) versus strain y that, in most cases, can be modeled with a simple equation, i.e.. [Pg.829]

A water parcel sampled from anywhere in the mixing zone should have a T-S signature that plots on the conservative mixing line established by the mixing end members. Thus, a 50-50 mixture of two adjacent water masses (or types) generates a temperature and salinity signature that is midway between that of the end members. Because of this linear relationship, the relative proportions of these end members in any admixture can be calculated from a system of two simultaneous equations ... [Pg.92]

Equation (3) implies that the field dependence of the mobility can become negative if a < E in (3a) or if E > 1.5 in (3b). This is a signature of positional disorder. The reason is the following. Suppose that a migrating charge carrier encounters a site from which the next jump in field direction is blocked because of poor electronic coupling. Under this condition the carrier may find it easier to circumvent that blockade. If the detour involves jumps against the field direction it... [Pg.19]

The conformal group C(2,2), if the Yang-Mills equations are defined in pseudo-Euclidean space having the metric tensor with the signature... [Pg.272]

Boltzmann s tombstone in Vienna bears the famous formula 5 = k log W (W = Wahrscheinlichkeit—probability) that was a signature of his audacious concepts. The alternative formula (13.69) (which reduces to Boltzmann s in the limit of equal a priori probabilities pa) was ultimately developed by Gibbs, Shannon, and others in a more general and productive way (see Sidebar 13.4), but the key step of employing probability to trump Newtonian determinism was his. Boltzmann was long identified with efforts to establish the //-theorem and Boltzmann equation within the context of classical mechanics, but each such effort to justify the second law (or existence of atoms) in the strict framework of Newtonian dynamics proved futile. Boltzmann s deep intuition to elevate probability to a primary physical principle therefore played a key role in efforts to find improved foundation for atomic and molecular concepts in the pre-quantum era. [Pg.451]

The second possibility is that prehistoric oxygen isotope signatures for different regions of the coast differ from modem values. Specifically, if water temperatures in northern California had been about 2-3° C warmer than at present when the prehistoric beads were produced (ca. 500-2000 cal B.P.), the northern California ellipse in Figure 8 would be shifted up by approximately 0.4-0.6 %o (an increase of 0.2%o in 8,sO equates to 1C reduction in temperature and vice versa). As a result, we would obtain the ambiguous isotopic data discussed above even though the beads were produced in northern California. [Pg.187]

Usually, this method is applied to enzymatic reactions, and the equilibrium IEs are obtained along with kinetic IEs that are of greater interest. An example is the deuterium IE on the reaction of acetone-c/6 with NADH, to form 2-propanol-fi 6 + NAD+. A mixture of acetone-c/6 and 2-propanol is prepared along with coreactants NADH and NAD+ at concentrations such that the reaction is at chemical equilibrium. Isotopic equilibration is initiated by adding enzyme. In this case the spectral signature lies in the NADH, but the measured maximum or minimum of absorbance provides the right-hand side of Equation (25) or (26) and thus a for each mixture. An estimate of AThh is needed to solve for each R in Equation (23) in order to fit the data to Equation (27), but after successive iterations the values of R and XEIE converge. [Pg.133]

Furthermore, the two equations, in which Ceulemans [10] expressed the relationship between the quasispin rank of a single-particle interaction operator and its time-reversal signature, may be summarized... [Pg.42]

Since isotopic fractionation is mass dependent, there will be a smooth relationship between effects observed in various isotopic ratios. In most cases of interest, the magnitude of fractionation and the fractional mass range are both small in an absolute sense, and to first order the degree of fractionation is approximately linear in mass 8m is proportional to dm, where 8m is a fractional measure (e.g., in per mil) of the fractionation effect between isotopes of mass m and m0 [Equation (1.1)] and 8m=m - m0. In elements of three or more isotopes, this is the signature by which fractionation is distinguished from specific isotope effects. If two or more isotopic ratios are observed to vary in this fashion appropriate for fractionation, it is usually considered that this is not an accident and that fractionation has indeed occurred (rather than two or more independent effects that depend on the nuclear identity of the isotopes in question). [Pg.78]


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See also in sourсe #XX -- [ Pg.250 ]




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