Velocity mean-mole

Kramers and Kistemaker evaluated the momentum transfer Co the wall by molecular impacts in a frame of reference moving with the mole mean velocity This has some algebraic advantage over working in the rest frame of the tube... 

The turbulent transport equations are obtained in the traditional treatment of turbulence by time averaging the unsteady-state transport equations, after substituting the concentration and velocity components by the sum of their mean values and the corresponding time-dependent fluctuations. The following expression is thus obtained for the (time) average of the number of moles N that are transferred per unit time through unit area, in the direction y normal to the wall ... 

A Mossbauer spectrum that has helped to corroborate the structure of cyclooctatetraene iron tricarbonyl is shown in Figure 27-12. The separation of the two absorption peaks in Figure 27-12 corresponds to a sample Doppler velocity of 1.23 mm sec-1. This Doppler effect means that there is the very small energy difference of 1.4 X 10 6 kcal mole 1 in the two transitions shown. 

We shall repeat the meaning and dimensions of all the notations Vg—linear velocity of flame propagation relative to the unburned mixture, cm/sec Ki—thermal conductivity at the theoretical temperature of combustion, cal/cm sec deg po—initial density of the mixture, g/cm3 n—concentration of the reacting substance, g/cm3 no—initial concentration of the reacting substance, g/cm3 L—calorific value of the mixture, cal/g To—initial temperature, deg Ti—theoretical temperature of combustion, T — To + L/c, deg E—heat of activation, cal/mole R—gas constant, cal/mole deg C—rate constant of a zero-order reaction, gr/cm3 sec C —rate constant of a first-order reaction, sec- 1 C"—rate constant of a second-order reaction, cm3/g sec. 

Equation 3.13 fulfills our basic objective in describing average molecular motion. However, inasmuch as we cannot ordinarily measure directly the average velocity of molecules or ions undergoing transport, it is advantageous to transform 0 into the flux density /, a parameter that is more directly observable. The flux density of a component is the number of moles carried through a unit areain unit time. It is related to that component s mean molecular velocity 0 and concentration c by... 

A special numerical relationship arises from the Michaelis-Menten equation when the initial velocity is equal to half the maximal velocity, that, is VQ = (V2)Vmax. Equation 5.24 then reduces to Km = [S0]. This means that Km is equal to the substrate concentration in moles per liter at which the reaction velocity is half its maximum value. 

Brisance — no info Decomposition Temperature — 180° with evolution of white fumes Detonation Velocity — 7132m/sec at density 1.35 Heat of Combustion at Cv and 18°— 519kcal/mole Heat of Formation at Cv — 74.6kcal/nole Hygroscopicity — very high Impact Sensitivity with 5kg Weight — at the heights 1.0 to 1.5 meters only 2 detonations out of 100 drops Initiation Sensitivity — detonates very difficultly at density 0.70 by means of 3g MF Power by CUP Method (Modified Trauzl Test) — 69.5% PA vs Tetryl 120% Stability — low... 

Let two bodies of the same gas, at the same temperature but at two different pressures (pand p ), communicate through a small hole of area A, all dimensions of which are small in comparison with the mean free path of the gas molecules. It can then be assumed that the Maxwellian distribution of velocities is essentially undisturbed and that the same number of molecules will enter the hole as would otherwise have collided with the corresponding area of wall surface. It will also be assumed that all molecules entering the hole will pass through to the other side. The /jet rate of effusion through the hole will be the difference between the numbers of moles flowing through the hole in unit time in the two directions ... 

The magnitude of the fluctuations in volume (dilatation) and density (condensation) associated with US wave is controlled by the properties of the medium and the applied forces. The velocity of sound in mixtures and suspensions will therefore be controlled by the mean density and mean compressibility as expressed by the Urick equation (see Eq.9.7-9.10). The equation can be formulated in terms of partial molar volumes by forming an identity between the volume fraction of the solute, its partial volume Vm2), the mean molar volume of the solution Vm) and the mole fraction Cm) as follows ... 

Here V, is the particle velocity of species i and y, the mole fraction of species i By particle velocities, we mean the vector-average velocities of millions of A molecules at a point. For a binary mixture of species A and B, we let Va and Vg be the particle velocities of species A and B, respectively. The flux, of A with respect to a fixed coordinate system (e.g., the lab bench), Wa, is just the product of the concentration of A and the particle velocity of A ... 

If there is no change of density during the reaction, the concentration can be suitably measured in moles per unit volume and the linear velocity will be denoted by if reactor is packed, the velocity v is taken to be the volume flow rate divided by the total cross-sectional area of the reactor. (The mean velocity through the interstices of the packed bed is v/e, where is the void fraction.) Also, let c/z) be the concentration of at a distance z from the inlet and r(ej, T) be the pseudo-homogeneous reaction rate in moles per unit reactor volume per unit time. If is the cross-sectional area of the reactor then in a unit of time... 

Ill the lower temperature interval (15.5° to 25.0°C.), E = 16.2 0.2 kcal. per mole over the entire range of pH. The difference in the pH dependence of the velocities at 25.0° and 34.9°C. causes the energy of activation calculated in this interval to lose its usual meaning, and in fact appear to depend on pH. No attempt will be made here to interpret the rather ambiguous result of such a calculation. 

From the kinetic theory of gases, without a knowledge of the law of distribution of velocities (i.e. of the way in which the number depends on v), we have found that the product of pressure and volume is a function only of the mean kinetic energy of the gas. But we have also an empirical law, the law of Boyle (1660) and Mariotte (1676), viz. at constant temperature the product of the pressure and volume of an ideal gas is constant. We must conclude from this that U, the mean kinetic energy per mole, depends only on the temperature of the gas. 

Gel filtration may be used as a means of detecting different conformations of a protein. Kornfeld (137) has found that the elution of Fe3+-saturated transferrin through Sephadex G-100 is retarded relative to the apoprotein. Similar results have been reported by Charlwood (139) who appears to have been able to resolve the three species (O-Fe, 1-Fe and 2-Fe) of transferrin by this method, indicating a 0.7% decrease in the Stokes radius of the molecule per iron atom bound. Differential measurements of sedimentation velocity showed about 1.8% increase in S20W upon binding of 2 iron atoms per mole (139). 

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