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Rate first kind

In these examples B is a base. The first example is called a secondary isotope effect of the first kind, the next one is a secondary isotope effect of the second kind. The distinction between these is that in the first kind bonds to the isotopic atom have undergone spatial (i.e., structural) change. Halevi has reviewed secondary isotope effects on equilibria and rates. [Pg.299]

Calculate tlie Fatal Accident Rate (FAR) for the first kind of accident. [Pg.534]

A first kind of these insurance products are called "catastrophe bonds" and consist in securitizing environmental risks in bonds, which could be sold to high-yield investors. The catastrophe bonds are able to transfer risk to investors that receive coupons that are normally a reference rate plus an appropriate risk premium. By these products, insurance companies limit risk exposure transferring natural catastrophe risk into the capital markets. In this way, with the involvement of the financial markets, their global size offers enormous potential for insurers to diversify risks. [Pg.34]

In some cases in which the rate of polymerization is of first order in monomer and for which there are reasons for believing a stationary state of the First Kind to prevail, it has been argued that Vt must be independent of [PJ (without, indeed, much evidence) and that therefore V must also be independent of [PJ. However, a termination reaction with monomer, though unlikely with most monomers, is not impossible, and in the Mayo plots it would be indistinguishable from monomer transfer. One possible mechanism for such a termination reaction is the formation of an allylic ion by abstraction of a hydride ion from the monomer [112] ... [Pg.144]

Case 3. If the propagation is a second-order reaction and the whole reaction curve is of second order, we have again necessarily a stationary state and this can only be of the First Kind. Thus, if we are dealing with formation of high polymers, such that rate = VPt... [Pg.145]

Consider now a stationary system, i.e., one in which p and q are invariant with time. If the stationary state is of the Second Kind, c = [catalyst] if it is of the First Kind, c is less than [catalyst]0, but proportional to it. The rate of polymerization is given by... [Pg.154]

For stationary systems of the First Kind and for non-stationary systems the rate equations are complicated, as they depend upon the kinetics of the initiation reaction. For such systems it is perhaps more profitable to concentrate attention upon the dependence of the DP on the reaction variables. Consider the following typical set of reactions, consisting of propagation, monomer transfer, and termination ... [Pg.156]

Here, e is the maximum electron density in the reactor, r is the radial position in the reactor, rt is the radius of the reactor cylinder, z is the axial coordinate, L is the height of the reactor (distance between the two electrodes), and J0 is the zero-order Bessel function of the first kind. Clearly, the electron density is a maximum at the center of the reactor (r = 0, z = L/2). The rate constants are ... [Pg.297]

We saw above that the polarographic current rises from zero to a current plateau. The plateau may be horizontal, or it might be gently sloping upwards we called this rise a residual current. Occasionally, there is also a current peak superimposed on the wave (see Figure 6.32). Such peaks are of two types, i.e. maxima of the first kind and maxima of the second kind. Both are caused by enhanced rates of mass transport at the Hg solution interface, as described in the following. [Pg.191]

In this context, it is again advisable to distinguish between rate constants of the first and second kind. kp, as introduced in Eqn. (6.41), obviously is the rate constant k of the first kind. It describes the growth of phase p when all the other phases form simultaneously. The rate constant kf] of the second kind describes the growth of phase p from phases (p- 1) and (p+ 1) only. [Pg.154]

Explicit expressions for the ratio (k /k ) of a multiphase reaction product layer have been presented in the literature, see, for example, [H. Schmalzried (1981)]. If k(2) of the second kind, which depends only on the properties of phase p, is calculated or measured for every phase p individually, it is possible to derive (from all NiiP, A p, and the molar volumes Vp) the rational rate constant k p] of the first kind, and thus eventually k in Eqn. (6.41). [Pg.154]

Highly active intermediate compounds of the first kind (free radicals and complexes) are always formed in free radical and catalytic processes. These compounds induce a much higher rate of the final product synthesis compared with their absence. [Pg.50]

Calculate the fatal accident rate (FAR) for the first kind of accident. The FAR (see Problem HZR.6) is a measure of the risk associated with an accident or event in units of number of deaths/1000 worker lifetimes (10 h). [Pg.808]

Based on the nature of the cytochromes, there are two kinds of photosynthetic bacterial reaction centers. The first kind, represented by that of Rhodobacter sphaeroides, has no tightly bound cytochromes. For these reaction centers, as shown schematically in Fig. 2, left, the soluble cytochrome C2 serves as the secondary electron donor to the reaction center the RC also accepts electrons from the cytochrome bc complex by way ofCytc2- The rate of electron transfer from cytochrome to the reaction center is sensitive to the ionic strength of the medium. Functionally, cytochrome C2 is positioned in a cyclic electron-transport loop. In Rb. sphaeroides, Rs. rubrum and Rp. capsulata cells, the two molecules of cytochromes C2 per RC are located in the periplasmic space between the cell wall and the cell membrane. When chromatophores are isolated from the cell the otherwise soluble cytochrome C2 become trapped and held by electrostatic forces to the membrane surface at the interface with the inner aqueous phase. These cytochromes electrostatically bound to the membrane can donate electrons to the photooxidized P870 in tens of microseconds at ambient temperatures, but are unable to transfer electrons to P870 at low temperatures. [Pg.180]

Here Jo and J are the Bessel functions of the first kind. The volume rate of flow is given by the formula... [Pg.49]


See other pages where Rate first kind is mentioned: [Pg.65]    [Pg.258]    [Pg.460]    [Pg.473]    [Pg.504]    [Pg.85]    [Pg.622]    [Pg.638]    [Pg.287]    [Pg.330]    [Pg.473]    [Pg.81]    [Pg.65]    [Pg.442]    [Pg.387]    [Pg.10]    [Pg.3]    [Pg.461]    [Pg.263]    [Pg.369]    [Pg.286]    [Pg.387]    [Pg.44]    [Pg.320]    [Pg.20]    [Pg.329]    [Pg.153]    [Pg.131]    [Pg.5]    [Pg.286]    [Pg.53]    [Pg.53]    [Pg.147]   
See also in sourсe #XX -- [ Pg.154 ]




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