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M site

A simple model for interactions between particles in an associating bulk fluid consists of a particle-particle potential and the interactions between sites belonging to different molecules. Supposing that each molecule has M sites, the potential of interaction between molecules 1 and 2 is [14]... [Pg.193]

For the extension to two dimensions we consider a square lattice with nearest-neighbor interactions on a strip with sites in one direction and M sites in the second so that, with cyclic boundary conditions in the second dimension as well, we get a toroidal lattice with of microstates. The occupation numbers at site i in the 1-D case now become a set = ( ,i, /25 5 /m) of occupation numbers of M sites along the second dimension, and the transfer matrix elements are generalized to... [Pg.449]

Thus 8(n,) is the energy of the row of M sites and v(n,-,n,+i) is the interaction energy of two adjacent rows. The partition function is then given in terms of the eigenvalues of this matrix as... [Pg.449]

VVe may, of course, generalize this sequential updating to entire blocks of m sites at a time. See [golesQO] for discussion. [Pg.285]

Domains were defined above as any physical regions of the lattice in which the sites are correlated both spatially and temporally. More precisely, let us define a domain of size D as a spatial sequence of m sites, +m, where... [Pg.394]

Thermodynamic equilibrium laws are applicable to the Schottky building units. However, there is a loss in intuition. In view of that conflict, the DSEs [11] make use of Kroger-Vink structural elements with the meaning of Schottky building units. This conversion is easily achieved by omitting all ideal lattice elements such as M on M sites, M M, and interstitial vacancies, V . This reads, for the example of Eqs. (5H7),... [Pg.529]

Rogers F.A., Vasquez K.M., Egholm M., Glazer P.M. Site-directed recombination via bifiinctional PNA-DNA conjugates. Proc. Nad. Acad. Sci. USA 2002 99 16695-16700... [Pg.175]

The gas phase partition function Qg s of the atom is the same however, since the atoms are immediately immobilized on a two-dimensional surface, we need to take the configuration of the adsorbed atoms into account in the transition state. Again we consider a surface containing M sites each with an area of a. The density of sites per area is Nq = M/A = 1 /a. The M sites are not necessarily free as some could be occupied already hence, the number of free sites will be M and 0 = M /M = (1-0a)-If we have N atoms adsorbed on these sites (we again use for the transition state Airmobile), the partition function for this system is given by... [Pg.116]

Vacant M site V" Divalent ions are chosen as an example, with MX as the compound formula... [Pg.422]

Only McDade et al. (2003b) report experimental data on the partitioning of Nb and Ta between olivine and melt. At 1.5 GPa they find Dm = 1 x lO " and Dia = 6 x 10 ", which indicates that is smaller than rNb (0.660 A). This will serve to exclude Pa (rpa = 0.78 A) from the M-sites in much the same way as it is excluded from Ml in clinopyroxene. Furthermore D h and Dxa are themselves two orders of magnitude lower in olivine than coexisting clinopyroxene (McDade et al. 2003b). For these reasons we suggest that Pa is substantially more incompatible in olivine than clinopyroxene. [Pg.95]

Figure 18. Electrostatic model fitted to partition coefficients for cations entering the large M-site in plagioclase, based on the experimental results of Bindeman and Davis (2000) and Blundy and Brooker (2003). The solid curve is a fit of the and Dll data of Blundy and Brooker (2003) to... Figure 18. Electrostatic model fitted to partition coefficients for cations entering the large M-site in plagioclase, based on the experimental results of Bindeman and Davis (2000) and Blundy and Brooker (2003). The solid curve is a fit of the and Dll data of Blundy and Brooker (2003) to...
Patwardhan, A.V. and Ataai, M.M., Site accessibility and the pH dependence of the saturation capacity of a highly cross-linked matrix. Immobilized metal affinity chromatography of bovine serum albumin on Chelating Superose, /. Chromatogr. A, 767, 11, 1997. [Pg.137]

Increased dealumination resulted in minor changes in the 29Si MAS-NMR spectra (Fig. lb), indicating that the zeolite structure remains intact. The appearance of sharper peak shoulders between -107 and -117 ppm is ascribed to a reduced contribution of Qm(nAl) Si(OSi)m n(OAr)n(OH)4 m sites (with 4 > m > n > 1). This, slightly shifted, contribution overlaps with the all-silica contribution and masks a clear distinction of the individual peaks in the parent material. [Pg.186]

One of the earliest studies was an MNDO-cluster treatment by Corbett et al. (1983) of the isolated interstitial hydrogen and the corresponding molecule. In this early study, the isolated H was found to be stable at the M-site in silicon. This is directly between two adjacent C-sites, where the C-site is directly between next-near-neighbor silicons. (We note that in these calculations, the C- and M-site energies are very similar.) It was not known at that time, however, that the BC site is the stable location for neutral isolated interstitial hydrogen (see Chapter 16). In the Corbett study, an H2 molecule was found to be stable (or at least, metastable) in the tetrahedral interstitial site when oriented along a (111) direction. The... [Pg.556]

Fig. 1. Location of various high-symmetry sites in the diamond structure. T is the tetrahedral interstitial site, H is the hexagonal interstitial site, B the bond center, and C is at the center of a rhombus formed by three adjacent Si and the nearest T. The M site is midway between two C sites it is also located midway between B and a neighboring H site. Fig. 1. Location of various high-symmetry sites in the diamond structure. T is the tetrahedral interstitial site, H is the hexagonal interstitial site, B the bond center, and C is at the center of a rhombus formed by three adjacent Si and the nearest T. The M site is midway between two C sites it is also located midway between B and a neighboring H site.
Metal vacancy at metal (M) site VM Nonmetal vacancy at nonmetal (Y) site Vy... [Pg.24]

Impurity metal (A) at metal (M) site Am Impurity non-metal (Z) at nonmetal site Zy... [Pg.24]

A metal atom N on an M site in a crystal MX would be written ... [Pg.41]

Consider the situation where two isolated atoms a and b, with electronic energies ea and /, are located above the — n and m sites in a monatomic substrate, with site (bond) energy a (/ ) (see Fig. 8.1(a)). Upon chemisorption... [Pg.141]

B( n) is the contribution to Bn of all the configurations in which n defects are assigned to m sites. The summation over m in Eq. (205) is essentially similar in character to that employed in 0. Retention of only m = 1, 2 corresponds to the familiar quasichemical approximation of order-disorder theory.33... [Pg.79]

Natural River pH=8 Particles 3.5 mgli (=5x10 8 M sites)... [Pg.380]

Hie linear macromolecule as simulated bv the chain of M sites on the volume-centered lattice allowing the self-intersection with minimum loop of 4 chain units. [Pg.27]

Once we open the system to allow exchange of ligands between the sites and the reservoir, the number of occupancy states of our system is not Q) (or 6 in the case of Fig. 1.1), but 2 " (or 2 = 16 as in Fig. 1.2). This is so because any site can be either empty or occupied, i.e., 2 states for each site, hence 2 " states for the m sites. Clearly, in an open system these 2 " configurations are not equally probable. For calculating the probabilities of the various events statistical mechanics provides a general recipe which differs from the classical method used above. The latter is applicable only when there are Q equally probable events (say, six outcomes of casting a die with probability 1/6 for each outcome). [Pg.5]

In the first sum, Q k) is referred to as the canonical partition function (CPF) of the system having a fixed number of k bound ligands. This quantity is itself a sum over terms, each of which represents one arrangement of the k ligands at the m sites. The terms could be different or equal, depending on whether the sites are different or identical. If all the sites are identical then we can take one representative, denoted by Cs(ifc), and multiply it by the number of such terms Q). In this case, the second equality on the right-hand side (rhs) of Eq. (1.1.19) holds. [Pg.8]

As in any treatment of a thermodynamic system one must first describe the system, the properties of which are to be examined. The typical system to be studied in this book consists of M adsorbent molecules, P, each having m sites. Each site can accommodate a single ligand molecule L. There are only two occupancy states of the site empty or occupied. For the entire molecule P there are m +1 occupancy states. For instance, in hemoglobin, the occupancy states are 0,1,2,3,4, according to the munber of bound oxygen molecules. [Pg.10]


See other pages where M site is mentioned: [Pg.437]    [Pg.213]    [Pg.399]    [Pg.450]    [Pg.452]    [Pg.217]    [Pg.75]    [Pg.422]    [Pg.422]    [Pg.107]    [Pg.107]    [Pg.107]    [Pg.110]    [Pg.112]    [Pg.71]    [Pg.217]    [Pg.166]    [Pg.613]    [Pg.613]    [Pg.630]    [Pg.22]    [Pg.91]    [Pg.68]    [Pg.2]    [Pg.27]   
See also in sourсe #XX -- [ Pg.592 , Pg.598 ]

See also in sourсe #XX -- [ Pg.592 , Pg.598 ]




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One Active and m Regulatory Sites

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