Energy driven distribution

The distribution, in thermodynamic terms, is said to be "energy driven."... 

For system A, it is characteristic to have a relatively very large enthalpy contribution (the slope of the van t Hoff curve is steep) with, conversely, a very low entropy contribution (the intercept is relatively small). The large value of the slope means that molecular forces dominate the distribution in favor of the stationary phase. It can be said that molecules are retained in the stationary phase as a result of molecular interactions. Thus, the change in enthalpy is the major contribution to the change in free energy and it can be said, in thermodynamic terms, the distribution is energy driven. 

The concentration profiles of the solute in both the mobile and stationary phases are depicted as Gaussian in form. In due course, this assumption will be shown to be the ideal elution curve as predicted by the Plate Theory. Equilibrium occurs between the mobile phase and the stationary phase, when the probability of a solute molecule striking the boundary and entering the stationary phase is the same as the probability of a solute molecule randomly acquiring sufficient kinetic energy to leave the stationary phase and enter the mobile phase. The distribution system is continuously thermodynamically driven toward equilibrium. However, the moving phase will continuously displace the concentration profile of the solute in the mobile phase forward, relative to that in the stationary phase. This displacement, in a grossly... 

Consider a physical system with a set of states a, each of which has an energy Hio). If the system is at some finite temperature T, random thermal fluctuations will cause a and therefore H a) to vary. While a system might initially be driven towards one direction (decreasing H, for example) during some transient period immediately following its preparation, as time increases, it eventually fluctuates around a constant average value. When a system has reached this state, it is said to be in thermal equilibrium. A fundamental principle from thermodynamics states that when a system is in thermal equilibrium, each of its states a occurs with a probability equal to the Boltzman distribution P(a) ... 

R. F. Kudritsky and D. G. Hummer, Quantitative Spectroscopy of Hot Stars , Ann. Rev. Astr. Astrophys., 28, 303, 1990 W. Schmutz, C. Leitherer and R. B. Gru-enwald, Theoretical Energy Distributions of Wolf-Rayet Stars , Pub. Astr. Soc. Pacific, 104, 1164, 1992 A.W. A. Pauldrach, T.L. Hoffmann and M. Lennon, Radiation-driven winds of hot luminous stars. XIII A description of NLTE line blocking and blanketing towards realistic models for expanding atmospheres , A ... 

Experiments were conducted in our laboratory to evaluate many of the dynamical expectations for rapid laser heating of metals. One of the aims of this work was to identify those population distributions which were characteristic of thermally activated desorption processes as opposed to desorption processes which were driven by nontbennal energy sources. Visible and near-infrared laser pulses of nominally 10 ns duration were used to heat the substrate in a nonspecific fashion. Initial experiments were performed by Burgess etal. for the laser-induced desorption of NO from Pt(foil). Operating with a chamber base pressure 2 x 10 torr and with the sample at 200 K, initial irradiation of a freshly cleaned and dosed sample resulted in a short time transient (i.e. heightened desorption yield) followed by nearly steady state LID signals. The desorption yields slowly decreased with time due to depletion of the adsorbate layer at the rate of ca. 10 monolayer... 

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