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Relaxation distance

Calculate the mole fraction of nitric oxide that ultimately will form, assuming that the elevated temperature and pressure created by the shock are sustained indefinitely. Calculate the time in milliseconds after the passage of the shock for the attainment of 50% of the ultimate amount this time may be termed the chemical relaxation time for the shock process. Calculate the corresponding relaxation distance, that is, the distance from the shock wave where 50% of the ultimate chemical change has occurred. [Pg.70]

On the basis of the SEXAFS derived bond distances one can attempt to derive the surface plane relaxation in the surface normal direction. By taking as a plausible reference a Co—Cu ideally non relaxed distance of 2.53 A, intermediate between the bulk Co and bulk Cu, our experimental values lead to conclude that there is a contraction of this distance (Fig. 5). The contraction is found to be 4 + 2% for the (111) face and 11 + 5 % for the (110) face. Moreover a small expansion of the second interlayer spacing (5 5%). is measured in the (110) case. The oscillatory damping of the first interlayer distances has been observed before and calculated, in parti-... [Pg.109]

Consider the propagation of a one-dimensional normal shock wave in a gas medium heavily laden with particles. Select Cartesian coordinates attached to the shock front so that the shock front becomes stationary. The changes of velocities, temperatures, and pressures of gas and particle phases across the normal shock wave are schematically illustrated in Fig. 6.12, where the subscripts 1, 2, and oo represent the conditions in front of, immediately behind, and far away behind the shock wave front, respectively. As shown in Fig. 6.12, a nonequilibrium condition between particles and the gas exists immediately behind the shock front. Apparently, because of the finite rate of momentum transfer and heat transfer between the gas and the particles, a relaxation distance is required for the particles to gain a new equilibrium with the gas. [Pg.265]

Wien, R.W., Morriset, J.D. and McConnell, H.M. (1972) Spin-label induced nuclear relaxation. Distances between bound saccharides, histidine-15, and tryptophan-123 on lysozyme in solution Biochemistry 11,... [Pg.225]

Eyes—focus Relaxed (distance vision) Constricted (near vision)... [Pg.20]

In this model the N atom of the NV -center belongs to the second subsurface layer. Partial and complete optimization of the geometry was carried out for the C33H3o[NV] cluster. For the first case, the relaxation of only N and C atoms, being the first and the second neighbors to N atom forming the first and the second subsurface atomic layers was taken into account. All the other atoms of the cluster were fixed. The starting and relaxed distances for the C-C and C-N pairs are presented in Fig. 2. [Pg.30]

Table I gives the fitting parameters for Equation 6, the values being chosen with the constraint that they also give the experimentally observed contact angle. The interaction and distortion energies, Eq and B, correspond to only a few hundred cal mole for the process (bulk water) - (adsorbed film), and it is important to realize that relatively minor energy effects are deteinnlnatlve of the adsorption and contact angle behavior. The energy relaxation distance, 1/S, is much larger for water adsorbed on PTFE than on PE, while the distortion relaxation distance, 1/8, is smaller. The picture is that water on PTFE is more weakly held than on PE, but more distorted in structure relative to bulk water. Table I gives the fitting parameters for Equation 6, the values being chosen with the constraint that they also give the experimentally observed contact angle. The interaction and distortion energies, Eq and B, correspond to only a few hundred cal mole for the process (bulk water) - (adsorbed film), and it is important to realize that relatively minor energy effects are deteinnlnatlve of the adsorption and contact angle behavior. The energy relaxation distance, 1/S, is much larger for water adsorbed on PTFE than on PE, while the distortion relaxation distance, 1/8, is smaller. The picture is that water on PTFE is more weakly held than on PE, but more distorted in structure relative to bulk water.
P° has the aspect of being an effective vapor pressure, it is always higher than P , and a physical interpretation is that P° is the hypothetical vapor pressure of a bulk liquid adsorbate whose structure is the same as that of the adsorbed film. On this basis, RT ln(P° /P ) is the local excess free energy of water in the adsorbed film resulting from structural perturbations relative to bulk water. The x parameter functions as a characteristic relaxation distance. [Pg.97]

Table I Includes the results of ellipsometric adsorption studies of water on a similar (and similarly prepared) PE to that of Ref. 14. (18) In addition, the adsorption was determined for a surface partially oxidized by treatment with an acid dlchromate solution. As might be expected, the effect of the introduction of polar sites reduces 6, Increases and Increases both Cq nd B. The relaxation distance for Is Increased, while that for the distortion term Is decreased. Systematic studies of this type should lead to a much better understanding of the nature of adsorbed films near F°. Table I Includes the results of ellipsometric adsorption studies of water on a similar (and similarly prepared) PE to that of Ref. 14. (18) In addition, the adsorption was determined for a surface partially oxidized by treatment with an acid dlchromate solution. As might be expected, the effect of the introduction of polar sites reduces 6, Increases and Increases both Cq nd B. The relaxation distance for Is Increased, while that for the distortion term Is decreased. Systematic studies of this type should lead to a much better understanding of the nature of adsorbed films near F°.
As no perfect vacuum exists, whether MS or IMS regime applies depends on the relaxation time for an ion to reach v versus the duration of constant E in experiment or, equivalently, on the relaxation distance A versus L— the ion path length during that duration. One would observe steady ion drift when A linear acceleration when A L (MS behavior. Figure 1.4b). During the acceleration gradually decreases from the initial value by Equation 1.5 to zero when v is reached. Hence the mean acceleration over tjx can be approximated as... [Pg.8]

A Relaxation distance (distance for ion to reach constant drift velocity) m ... [Pg.329]

The significance of k in (3) is the same as in (2), that of similar to that of t in (2) L/ is one-sixth of the mean square distance in an infinite lattice between the point where the neutron becomes thermal to the point to which it has diffused when it gets absorbed. Lp is also called the diffusion length of thermal neutrons in the lattice because the n decreases with an exponential relaxation distance Lp... [Pg.456]

Since the effectiveness of a black rod varies only logarithmically with the radius of the rod, small errors in the observed relaxation distance would have a very great effect on the effective rod radius calculated from the observed change in It was therefore thought more advisable to assume the Placzek rod boundary conditions (used also in the design of the W safety rods) and, on the basis of the present theory, to calculate a which could be compared directly with the experimental C- By this procedure we can arrive at an estimate of the adequacy of the W safety rod design, since the theory used for W is essentially identical to the present 2-group theory. [Pg.564]

In the BC zone, the relaxation distance also increases by chain squeezing and, therefore, Zg is multiplied by a factor or As a result,... [Pg.423]

However, according to the pseudo-cross-link model, the Payne effect can be ascribed to the interaction between the surface of carbon black and the chemical group at the polymer terminal, which is also adsorbed on the black surface but more strongly than the pseudolink in a chain. This causes a larger loss when the terminal begins to slip. The relaxation time or relaxation distance are almost the same as that of the B-chain. This assumption is compatible with the constant critical amplitude, the parallels between the dynamic loss, the reinforcing ability of carbon black, and the independence of the amplitude on the molecular weight of matrix rubbers. The relaxation time T and the distance d are to be expressed respectively as... [Pg.440]

According to the concept of pseudo-cross-link, the critical value corresponds to the critical relaxation distance for the pseudo-cross-link of the smallest size. The energy dissipation takes place by the migration of the pseudolink of the smallest size of b of 2. The relaxation time tj, and distance d are given respectively as... [Pg.443]


See other pages where Relaxation distance is mentioned: [Pg.713]    [Pg.411]    [Pg.25]    [Pg.220]    [Pg.39]    [Pg.71]    [Pg.513]    [Pg.312]    [Pg.420]    [Pg.210]    [Pg.121]   
See also in sourсe #XX -- [ Pg.97 ]




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